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2016 Quarter 3 Vol. 2, No. 3

Progress in Printing and Packaging Application Awards Given at RadTech 2016

3-Ketocoumarins for UV LED

Combining Oxiranes and Oxetanes

BUYERS GUIDE EDITION

Official Publication of RadTech International North America


We create chemistry that makes surfaces love UV/EB curing.

In close collaboration with our customers and their value chain networks, we search for solutions to meet the market needs of today and the challenges of tomorrow. Our technical experts provide advice on ink, overprint varnish and coating guidelines to develop the best solutions leading to faster curing rates, good adhesion to a wide range of substrates, increased productivity and lower production costs. At BASF, we create chemistry. www.basf.us/dpsolutions


FEATURES 12

RadTech 2016 UV/EB Technology Conference and Exhibition Attendance up, awards given at bi-annual event.

16

Several critical issues drive technological development in UV/EB resin technology today, particularly within the fast-growing area of food packaging. These include the relationships between cure energy, viscosity and molecular weight. By Paul Share, senior product development scientist, printing and packaging, BASF Corporation

E N V I R O N M E N TA L LY F R I E N D LY ° E N E R G Y E F F I C I E N T

RADTECH2016 C H I C A G O ° M AY 1 6 -1 8 ° H YAT T R E G E N C Y

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Cover photo: Winning poster at RadTech 2016, designed by Austin Smolt-Saenz, University of Iowa.

31

35

Annual Buyers Guide Design of New 3-Ketocoumarins for UV LED Curing By modifying the physical-chemical properties of 3-ketocoumarins, new 3-ketocoumarins with good solubility, high reactivity and low yellowing for clear and pigmented coatings are possible. By Andrea Bernini Freddi, Marika Morone and Gabriele Norcini, IGM Resins Gerenzano (VA), Italy

DEPARTMENTS

2 | UV+EB Technology • Issue 3, 2016

Advances in Electron Beam Curing in Wide Web Flexible Package Printing Flexographic ink systems and web offset flexible package printing have both seen optimizations that allow for flexible package printing with near zero VOCs and low migration inks that are well suited for food packaging applications. By David A. Biro and Jim Bishop, Sun Chemical, USA

46 President’s Message............................................. 4 Association News................................................. 6 Technology Showcase........................................ 24 Industry News..................................................... 54 Patent Watch....................................................... 55 Regulatory News................................................ 62 Calendar.............................................................. 64 Advertisers’ Index............................................... 64

Electron Beam Cross-Linking of Polyolefin Films for Various Packaging Applications Since the development of low-voltage electron beam accelerators in the range of less than 300 kV, EB cross-linking has found new applications and markets, particularly in the packaging industry. By Im Rangwalla, market development manager, Energy Sciences, Inc.

ON THE COVER

The cover was finished by Royle Printing Company, Sun Prairie, Wisconsin, using a multi-step UV-curing process called Rough Reticulated Strike-Through. First, the 4-color process was laid down and a UV varnish was applied as a spot application in the areas that did not receive the gloss UV treatment (photograph and copy). The UV varnish was cured with UV lights, and then an LED curing system was used to cure the 4-color process inks. A flood gloss UV was applied over the entire cover, which “reacted” to the UV varnish and created the matte varnish – staying glossy in the areas that were knocked out to receive the gloss UV. The final step was a pass under another UV curing system to cure the coating. This process was performed in one pass on press.

Recent Advances in Low Viscosity, Low Migration, Fast Curing UV/EB Resin Technology

56

Combining Oxiranes and Oxetanes to Enhance Kinetics and Improve Physical Properties Oxetane addition to formulations is correlated to improvements in polymerization kinetics and polymer properties during dark cure. By Sara M. Kaalberg and Julie L. P. Jessop, Department of Chemical & Biochemical Engineering, University of Iowa

uvebtechnology.com + radtech.org


CHAMPIONS THIS ISSUE TECHNOLOGY 2016 Quarter 3 Vol. 2, No. 3

RadTech International North America’s Editorial Board facilitates the technical articles featured in UV+EB Technology. Smaller teams of Issue Champions review and approve articles and provide overall content management for each issue, as needed. If you are a member of RadTech and are interested in serving on the Editorial Board, contact Gary Cohen at gary@radtech.org.

Syed T. Hasan

Editorial Board Co-Chair Key Account Manager, Security Inks BASF Corporation

Charlie (Chunlin) He Lead Materials Scientist Full Spectrum Laser LLC

COLUMNS 8

EB Curing Technology Question & Answer

How does electron beam curing fit with digital printing technology? By Stephen C. Lapin, Ph.D., industry consultant, SCLapin Consulting LLC

10

UV Curing Technology Question & Answer

What’s in a Word? Notes on the RadTech UV Glossary By R.W. Stowe, director of applications engineering, Heraeus Noblelight America LLC

Mike Higgins

East Regional Sales Manager Phoseon Technology

Chris W. Miller

Editorial Board Co-Chair Manager, Research & New Technology Estron Chemical

UV+EB TECHNOLOGY EDITORIAL BOARD Chris W. Miller, Estron Chemical Co-Chair/Editor-in-Chief Syed Hasan, BASF Corporation Co-Chair/Editor-in-Chief Susan Bailey, IGM Resins Brian Cavitt, Abilene Christian University Byron Christmas, Professor of Chemistry, Retired Charlie He, Full Spectrum Laser LLC Mike Higgins, Phoseon Technology

uvebtechnology.com + radtech.org

Molly Hladik, ACTEGA North America Mike J. Idacavage, Colorado Photopolymer Solutions Sudhakar Madhusoodhanan, Valspar Maria Muro-Small, Spectra Group Limited, Inc. R.W. Stowe, Heraeus Noblelight America LLC Huanyu Wei, FiberMark Jinping Wu, PolyOne Corporation Sheng “Sunny” Ye, 3M

R.W. Stowe

Director of Applications Engineering Heraeus Noblelight America LLC

Huanyu Wei

R&D, Senior Research Scientist Neenah Paper Inc.

UV+EB Technology • Issue 3, 2016 | 3


President’s Message Ready for the (R)evolution?

P

erhaps the biggest frustration among our UV/EB community is the knowledge that yes, we really do have a solution that is better, faster and cleaner – but, as most of us have learned, persuading traditional manufacturers to adopt any potentially game-changing process, including ours, is not easy. For years, many of us viewed our work in UV/EB as the start of a manufacturing revolution. While it might be argued that Peter Weissman enabling UV/EB applications, such as fiber optics, made a tremendous impact, a more widespread, real revolution is emerging in our economy in the way we make things and serve our customers. In many cases, it is not the manufacturers we are familiar with that are driving the change, but new entrants that are moving fast to market and looking for solutions. Beer is a great example. The number of craft brewers in the US grew by 20% to nearly 3,500, according to recent data, with sales growing at a similar rate. At the same time, the overall beer market is essentially flat. New companies developing novel products and packaging not only are offering different opportunities, but forcing the bigger players to pivot as well. In fact, from automobiles (who would have thought just a few years ago that Google and Apple would be developing a car – or, perhaps more correctly, electronic devices on wheels) to food packaging to energy generation and delivery, the landscape is shifting to the need for speed, customization, electronic features and sustainability – perfect for UV/EB. This movement was on display at RadTech 2016 (see recap of the event on page 12) as we featured sessions on applications and innovation in fields ranging from 3D printing to the automotive industry. At our awards dinner, we recognized developments in next generation technology, such as 3D printed composites; new products, including holographic films for food packaging; and innovative ways of making everyday items, like weather stripping and lids for pails. UV/EB is well positioned for “revolutionary” new ways to make things (think 3D printing, UV LED and inkjet). At the same time, our technology has a unique characteristic in the ability to “evolve” to meet ever greater opportunities down the road. It is our job to foster emerging trends, while helping ensure that our technology may meet (and exceed) customer and regulatory demands through the sharing of information and the development of educational opportunities. We hope you join us as we work together to advance our technology and navigate new opportunities. We look forward to seeing you at our Fall Meeting in Austin, Texas, November 2-3; and uv.eb WEST 2017, taking place early next year in San Francisco, California. And, as always, please call on us if we may ever assist you! Peter Weissman President, RadTech International North America Quaker Chemical Corp.

TECHNOLOGY An official publication of: RADTECH INTERNATIONAL NORTH AMERICA 7758 Wisconsin Avenue, Suite 302 Bethesda, Maryland 20814 240-497-1242 radtech.org EXECUTIVE DIRECTOR Gary M. Cohen gary@radtech.org SENIOR DIRECTOR Mickey Fortune

BOARD OF DIRECTORS

President Peter Weissman – Quaker Chemical Corporation President-elect Lisa Fine – Joules Angstrom UV Printing Inks Secretary Eileen Weber – Red Spot Treasurer Paul Elias – Miwon North America Immediate Past-President Don Duncan – Wikoff Color Corporation Board of Directors Jo Ann Arceneaux – Allnex USA Inc. Rick Baird – The Boeing Company Mark Gordon – INX International Ink Company Jennifer Heathcote – Phoseon Technology Joshua Lensbouer – Mannington Mills George McGill – Zeller + Gmelin Corporation Alexander Polykarpov – AkzoNobel Beth Rundlett – Katecho, Inc. Jeremy Teachman – Sun Chemical Corporation Alrick “Al” Warner – Procter and Gamble Xiasong Wu – DSM Functional Materials

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2150 SW Westport Drive, Suite 101 Topeka, Kansas 66614 785-271-5801 petersonpublications.com Publisher Jeff Peterson

National Sales Director Janet Dunnichay

Art Director Becky Arensdorf

Managing Editor Dianna Brodine

janet@petersonpublications.com

dianna@petersonpublications.com

Contributing Editors Circulation Manager Lara Copeland Brenda Schell Nancy Cates brenda@petersonpublications.com ENews & Website Developer Jen Clark

4 | UV+EB Technology • Issue 3, 2016

uvebtechnology.com + radtech.org


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Association News Sustainability Conference to be Held in Conjunction with SGIA Hosted by the Sustainable Green Printing Partnership, the 2016 Printing Industry Sustainability Conference will take place September 13, 2016, in Las Vegas, Nevada. The 2016 Printing Industry Sustainability Conference is dedicated to showcasing the leading practices and emerging challenges print professionals need to know to enhance sustainability programs. Through a mix of peer-led case studies and roundtable dialogues, this sustainability conference is a unique opportunity to gain actionable insights that can be used to immediately improve performance, identify opportunities for business and set better sustainability goals. RadTech is pleased to be an event sponsor. Information and registration can be found at http://2016conference.sgppartnership.org/. RadTech Sets Date for Fall Member Meeting On November 2-3, 2016, RadTech will host its Fall Member Meeting in Austin, Texas. Austin is a major hub of semiconductor, consumer electronics and technology companies, such as 3M, Apple, Hewlett-Packard, Google, AMD, Applied Materials, Cirrus Logic, Cisco Systems, Intel Corporation, National Instruments, Samsung Group, Silicon Laboratories, Oracle Corporation, Hostgator and United Devices. Please plan to join RadTech members as we discuss new initiatives for our industry in UV LED, 3D Printing, Printing & Packaging, Automotive and Education. An EHS meeting also will be held where members will continue the conversation about TSCA Reform and other pressing issues for our industry. RadTech China Announces Conference Details Co-organized by RadTech China and Anqing Science and Technology Bureau and Administrative Committee of Anqing Hi-Tech Industrial Development Zone, the 17th RadTech China Annual Conference together with the First Summit Forum on New Chemical Material Industry in Anqing will be held September 7-9, 2016 at the Anqing County Garden Phoenix Hotel in Anqing City, Anhui Province, China. RadTech China 2016 will invite government officers, famous scholars and entrepreneurs to share idea and information about industrial policies, frontiers and directions, application achievements, market situations, development trends of UV/EB technology and much more. For more information, visit www.radtechchina.com. Syed Hasan Appointed as Co-Chair to RadTech Editorial Board Syed Hasan, key account manager for Security Inks, BASF, has been appointed as co-chair to the RadTech Editorial Board, which has oversight responsibilities for UV+EB Technology. Hasan began as a chemist with BASF Coatings in 1989. After completing his MBA, Hasan moved into sales with BASF’s Coating Raw Materials division; he has since held regional and key account management 6 | UV+EB Technology • Issue 3, 2016

positions for North American and, from January 2013 to May 2016, he managed the new business development and innovation pipeline. Hasan accepted a key account manager role for Security Inks on June 1, 2016, reporting into Southfield, Michigan. ESF Accepting Registration for Short Courses State University of New York College of Environmental Science and Forestry, Syracuse, New York, has opened registration for two professional development short courses for $295: Principles of Energy Curing Technologies and Basics of UV-Curable 3D Printing. Participants who register prior to Labor Day can receive a special BOGO (Buy One/Get One) deal. Both participants must take the same course. RadTech members also will receive an additional 10 percent discount, and a group discount of 20% off for three or more attendees is available. In addition, confirmation has been received that the rates for ESF advanced courses will not change next year. The costs for each of the three advanced courses are as follows: • For credit (3 credits per course): $1,359 (NYS residents), $2,775 (out-of-state) per course • Not for credit: $1,359 per course for all (10% discount, $1,223.10, for RadTech members; 20 percent discount, $1,087.20, for groups of three or more non-credit participants from the same organization) For more information, visit www.esf.edu. RadTech Issues Call for Abstracts for uv.eb WEST 2017 Abstracts now are being solicited for the upcoming uv.eb WEST 2017 Materials + Manufacturing Summit, to be held February 27-March 1 at the Embassy Suites San Francisco Airport Waterfront Hotel in San Francisco, California. A working schedule has been posted to the website to provide suggested conference topic areas, including 3D Printing, Flexible & Printed Electronics, Displays, General Electronics, New Materials, Photoinitiators for UV LED + Advanced Applications, Inkjet/Digital Printing, UV LED, Food Packaging, Food Safety/Disinfection and New Markets/ Applications for UV+EB Technology. To submit an abstract for consideration, please email the presentation title and 150-200 word abstract in the body of an email (no attachments please) by August 26, 2016, to mickey@radtech.org. n

www.uvebwest.com uvebtechnology.com + radtech.org


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EB CURING TECHNOLOGY QUESTION & ANSWER

Q. How does electron beam

A.

curing fit with digital printing technology?

When most people think about electron beam (EB) curing for printing and packaging, they think about wide- and mid-web high-speed printing of folding cartons and flexible packaging. EB certainly is well established in these areas. Web offset is the dominant EB printing technology, with EB flexo making nice gains as wet-trapping inks and press technology continue to improve. But, what about digital printing? Is there a role for EB in digital printing technology? Growth in Digital Printing Digital printing technology is growing at an astounding rate. This includes digital printing stations integrated into conventional presses to add variable information and complete digital press solutions. Digital press technology is a great fit for short runs and customized print jobs, but breakeven points for digital vs. conventional printing continue to grow as digital press speeds increase. There is almost no segment of the printing industry that is untouched by digital printing technology. This includes commercial printing, POP displays, signs, banners, decorative surfaces, building panels and floor tiles. You name it, and digital either already is established or making inroads. In the packaging world, digital already is well established in label printing and is growing for carton printing. Digital also has been introduced for printing on ridged packaging, including cans, bottles and cups. Digital printing is only just beginning to be established in the flexible packaging world. There certainly is an opportunity for digital printed flexible packaging given the high number of SKUs, local brands and promotional packaging campaigns. EB technology could be an excellent fit for digital printed flexible packaging. The main factors that drive the use of EB in conventional package printing are consistent cure, low odor, low migration, excellent appearance and resistance properties. These same factors should help drive the use of EB in digital package printing. Opportunities in technology and consumables Most digital printing can be broadly classified into inkjet or electrographic imaging processes. There are a number of subclasses of each type. UV curing of inkjet inks is well established using both mercury lamps and LED sources. 8 | UV+EB Technology • Issue 3, 2016

Advantages of UV curing of inkjet include fast curing, excellent print quality, excellent adhesion to a variety of substrates and excellent resistance properties. In order to jet properly, inkjet inks must be very low viscosity. This limits UV inkjet ink compositions to a relatively small selection of low molecular weight acrylate functional monomers. The use of these monomers can make it challenging to produce low-odor, low-migration inks. Additionally, photoinitiators that give fast curing of UV inkjet inks may not be ideal for low migration properties. Electron beam curing of inkjet inks eliminates the need for photoinitiators and may expand the selection of monomers that can be used while maintaining low migration properties. Another advantage of EB inkjet may be printing on porous substrates, such as fabrics, where the beam can penetrate and cure areas that are not easily penetrated by UV. Much of the initial growth in inkjet package printing is occurring in narrow web formats. Sealed tube EB “lamp� based systems (UV+EB Technology, 2016 Issue 2, p. 12) are ideal for narrow formats. Actively pumped EB systems may be a better fit as inkjet press technology expands to wider webs and faster speeds. A current challenge for EB inkjet exists in jobs that require white ink layers. Separate curing of the process colors and white is needed to prevent mixing. This could be achieved using two EB systems; however, this greatly increases the size and cost of the system. A fundamental challenge of UV/EB inkjet for flexible packaging is the thickness of ink layers. Inkjet inks have low pigment concentrations to allow jetting. This mean relatively thick (on the order of 10 microns) ink layers are needed to reach the desired optical density. This is a problem when printing on flexible packaging films, which may only be 12 to 20 microns thick. Another digital printing technology involves electrographic imaging with liquid toner-based ink systems. HP Indigo is by far the leader in this category, with a large number of 13-inch-wide web presses installed worldwide for label printing applications and a 30-inch-wide web format that uvebtechnology.com + radtech.org


“A fundamental challenge of UV/EB inkjet for flexible packaging is the thickness of ink layers. Inkjet inks have low pigment concentrations to allow jetting. This mean relatively thick (on the order of 10 microns) ink layers are needed to reach the desired optical density.” greatly expands the potential for digital printing of flexible packaging.

and very heat resistant, which serves to protect the inks during the heat sealing process. There also is evidence to suggest the inks themselves may be slightly crosslinked by EB, further enhancing the resistance properties. Cured EB OPVs can have outstanding high-gloss, low-gloss or soft-feel properties. EB also enables the combination of multiple finishes on a single package. EB-cured laminating adhesives also may be an option to consider for printed flexible packaging. The instant curing adhesive technology is a good fit for the instant digital printing technology, resulting in packaging that is immediately ready for slitting, pouching or filling. With the growth of digital technology for printing and packaging, opportunities exist for electron beam curing n

Further conversion of printed film is needed to produce functional flexible packaging. This could involve lamination or the application of a protective overprint varnish (OPV). EB appears to be an excellent choice for these finishing steps. HP Indigo inks are thermoplastic in nature and may smear or transfer during the heat sealing used to form and fill the packages. Cured EB OPVs are crosslinked

Stephen C. Lapin, Ph.D. Industry Consultant, SCLapin Consulting LLC, sclapin@gmail.com

Alberdingk® Water-based UV-Curable Dispersions for Printing & Packaging Alberdingk Boley offers a full line of waterborne emulsions and polyurethane dispersions including UV-curable dispersions for wood, metal, concrete, plastics, glass, and exible substrates (leather/synthetic leather, textiles, paper, and plastic lms).

LUX 515 Adhesion to exible lm substrates LUX 220 Hard, scuff resistant top coat, excellent chemical resistance, adhesion to multiple exible lms LUX 399 Fast water release, resoluble in water

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UV+EB Technology • Issue 3, 2016 | 9


UV CURING TECHNOLOGY QUESTION & ANSWER

Q. What’s in a Word? Notes on the

A.

RadTech UV Glossary

In the English language, it’s quite common for one word to mean any of several different things. Often, if it wasn’t for context, it might be difficult to figure out what actually was meant. However, when it comes to science and engineering, more precision is demanded. For example, what does it mean to describe something as “round?” Purveyors of Precise Terminology might contend that “round” essentially is meaningless, and that a round object must be either circular, cylindrical or spherical – no more, no less. Within science and engineering, there is a compulsion to use only the correct terms when referring to phenomena or measures to ensure clarity and understanding. A number of technical dictionaries and glossaries for a variety of sciences are available – some are highly specialized and many are comprehensive and extensive. Today’s industrial applications employ combined technologies, and there is a need for convergence of correct terms. In recent years, and after a UV campaign begun in 1995, we have gradually managed to replace the common general term “intensity” with the correct optical term “irradiance.” Irradiance is the measure of the flux of radiant energy per unit area, typically at a surface, in watts/cm² (or mW/cm²), while the term “radiance” refers to energy emitted from a source. Oddly, “intensity” actually has a very specific optical definition of watts per steradian (W/sr) – probably not what was meant. A way to look at the distinction between generic common use and technical meaning is to assess whether the term has units of measure associated with it.

Charles Lutwidge Dodgson (Lewis Carroll), Through the Looking Glass, 1871, Chapter VI – Illustrations by John Tenniel

found on the RadTech website at http://www.radtech.org/ intro-to-uv-eb/uv-glossary.

In an effort to “tune up” the terms we use, the UV Measurement Group of RadTech North America assembled a glossary of terms appropriate for UV curing technology. Introduced a few years ago, this glossary is intended to be compact, easy-to-use and correct – but, not technically deep – and consistent with UV terms as they apply to crossdisciplines of optics, physics and chemistry. A number of sources in these disciplines were used in the assembly of the glossary.

A few readers always are surprised by some of the terms and by the fact that they aren’t what the readers thought them to be. We all use common words – such as “intensity” and “light” – in a generic sense, but may forget that the terms are specific when used in technical context. For example, ultraviolet (UV) is characterized by a very specific region of the electromagnetic spectrum, while light is defined as only the visible portion of that spectrum. Even so, we hear the expression “UV light” when, in fact, there may be no such thing!

A few terms have been revised and some added, with care to keep the glossary to a compact size. The glossary can be

Another term – often the subject of discussion – is the term “dose.” Dose is a defined EB and high energy or ionizing

10 | UV+EB Technology • Issue 3, 2016

uvebtechnology.com + radtech.org


radiation term, but because UV and EB are related by chemistry and “grew up in the same family,” the term leaked from the electron beam lexicon to UV. We should make an effort to avoid having one term with two different definitions and meanings. The EB and ionizing energy definition is based on energy absorbed per unit mass (or unit volume), and the EB units are the gray (Gy) or kilogray. (The rad, the corresponding cgs unit and equivalent to 0.01 Gy, is disappearing from use.) For UV and non-ionizing radiant energy, we measure photon energy delivered per unit area, and the preferred term is “exposure.” Accepted alternates in use in UV curing technologies are “energy” or “energy density” and the units are joules/cm² or mJ/cm². Solar UV exposure typically is expressed in J/m². One of the most common problems we have encountered in the design and troubleshooting of production UV curing and UV exposure systems is the incorrect or vague use of terms and units. Almost all radiometer manufacturers have taken care to use proper terms and units, but many material

TECHNOLOGY

It is hoped that the RadTech UV Glossary continues to help in the consistent use of technical terms used in our technology and industry, as well as in technical papers, articles, advertising and presentations. n

R.W. Stowe

Director of Applications Engineering Heraeus Noblelight America LLC dick.stowe@heraeus.com

SHARE YOUR KNOWLEDGE WITH OUR READERS UV+EB Technology, the official magazine of RadTech International North America, promotes the use and benefits of ultraviolet and electron beam curing technologies. It is distributed to more than 15,000 readers, including end users, formulators, raw material suppliers and service providers on a quarterly basis.

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UV+EB Technology features non-commercial content, including technical articles, case studies, application highlights and Q&As. All technical content is reviewed by RadTech’s Editorial Board. For complete editorial guidelines: uvebtechnology.com dianna@petersonpublications.com UV+EB Technology • Issue 3, 2016 | 11


RADTECH AWARDS

RadTech 2016 UV/EB Technology Conference and Exhibition Attendance Up, Awards Given in Several Categories With attendance up five percent over the 2014 event, RadTech 2016 has been deemed a success. More than 80 exhibitors and 1,400 attendees gathered in Chicago for three days in May to discuss the latest innovations in the ultraviolet and electron beam industries, while also celebrating a number of award honorees. Panels addressed food packaging, 3D printing, innovation

High-profile panels at RadTech 2016 brought together UV/EB users and suppliers to discuss the emerging impact of the technology in diverse applications. The Food Packaging Panel contained a mix of industry experts in the formulator, regulatory and legal arenas, as well as a CPG company, Nestlé. While there were some light-hearted moments, Nestlé made a serious proposal that there should be complete transparency of all ink/ coating/adhesive/press chemical raw materials to Nestlé via nondisclosure agreements. In addition, there were some somber moments as the panel discussed the prospect of intervention by governments of new laws regarding migration, the potential of over-regulation and the process of establishing uniform standards for food packaging print around the world. These are all tough problems and complex issues, but the first step to resolution is to get them on the table where knowledgeable experts can propose potential solutions. Commentary by Don Duncan, session chair, Wikoff Color

Radtech 2016’s Innovation Panel included Sharon Tracy, Steelcase; Alrick Warner, P&G; Christopher Seubert, Ford Motor Company; Todd Fayne, PepsiCo; Robin Wright, 3M; and moderator Lee Goldberg of Product Design and Development and Medical Design Technology magazines.

The 3D Printing Panel discussed the latest advancements in 3D printing using UV technologies. Thought leaders in materials, equipment and end uses for UV technologies in 3D Printing participated, including Victor Latour, supervisor of digital design, Stoopid Buddy Stoodios; Sumeet Jain, director - market development, Arkema Inc., Sartomer Business Unit; Lance Pickens, CEO and founder, MadeSolid; Mike Idacavage, vice president, business development, Colorado Photopolymer Solutions; Brian Adzima, materials scientist, 3D printing, Autodesk; and Alex Mejiritski, president, Spectra Group Limited.

Awards presented for service, innovation and education

Service David Harbourne of Heraeus was honored for his longtime leadership and service to RadTech and the UV/EB community. This is only the second time RadTech has bestowed such recognition. Student Awards RadTech has developed several initiatives to engage and support students, with over 40 students attending 12 | UV+EB Technology • Issue 3, 2016

uvebtechnology.com + radtech.org


RadTech 2016 as guests of the organization. These students also will be offered gratis membership in the association, and two student competitions were held.

Second place: Ozlem Kubra Akdogan, Eastern Michigan University; Professor Vijay Minnari. Akdogan is a polymer engineer, pursuing a Masters degree in Polymers and Coatings. She is a member of Dr. Mannari’s green chemistry and engineering team, with a research interest in improving design, synthesize and formulation of bio- based UV curable coatings.

Posters RadTech partnered with the Technical Association for the Graphic Arts (TAGA) in offering awards to students who developed posters showing the benefits of UV/EB technologies. The first place winner is featured on the cover of this magazine.

Papers More than 100 abstracts were received for presentations for RadTech 2016. The RadTech Technical Committee carefully reviewed and commented on all of these abstracts, helping to achieve high standards for the RadTech Technical Conference. The Committee also was responsible for selecting the Best Paper Awardees.

David Harbourne of Heraeus was honored for his longtime leadership and service to RadTech and the UV/EB community.

First Place: Austin SmoldtSaenz, University of Iowa. Smoldt-Saenz is a recent graduate from the University of Iowa with a BFA in Graphic Design.

UV+EB

RadTech Technical Committee: Mike Idacavage, Colorado Photopolymer Solutions; Chris Miller, Estron; Julie Jessop, University of Iowa; Susan Bailey, IGM Resins; Alexander Polykarpov, Akzo Nobel (not shown); Joel Schall, Henkel (not shown); and Molly Hladik, chair, ACTEGA North America (not shown).

Best Student Paper: Sara Kaalberg, University of Iowa; Co-Author: Professor Julie L.P. Jessop Paper Topic: Combining Oxiranes and Oxetanes to Enhance Kinetics and Improve Physical Properties (see page 56) Best Paper: Marika Morone, IGM Resins; Co-Authors: Andrea Bernini Freddia, Gabriele Norcinia

E N V I R O N M E N TA L LY F R I E N D LY ° E N E R G Y E F F I C I E N T

RADTECH2016 C H I C A G O ° M AY 1 6 -1 8 ° H YAT T R E G E N C Y

RadTech 2016 Chicago IL, May 16-18

Second Place: Maria Padron, University of Iowa. Padron is a designer and artist, originally from Cordoba, Argentina, who earned her M.A. in Art from the University of Iowa in May. Experiments RadTech challenged college students to create a fun, interesting experiment that showcased UV-curable materials and would be suitable for high school classrooms. Participants submitted a lab manual, as well as video demonstrations, which can be viewed by visiting https://www.youtube.com/ playlist?list=PLPxbgQTtCrhNVvex9Cp4Y5fyZpEWzwoym. First Place: Sierra Dell, Penn State York; Professor Andy Landis. Dell is entering her senior year at Penn State York in pursuit of a bachelor’s of science degree in Biology. uvebtechnology.com + radtech.org

Paper Topic: Design of New 3-Ketocoumarins for UV LED Curing (see page 46) Innovation awards RadTech 2016 also recognized companies that use UV/EB technologies. At the RadTech 2016 awards dinner, several innovative, cutting-edge applications were celebrated. Continuous Composites (CC3D) CC3D has developed a new 3D printing process to print continuous fiber with UV-curable resin; they are reportedly the only company in the world 3D printing continuous fiber with thermoset epoxy and the only company to successfully print continuous fiber into free space. With a focus on functional composites additive manufacturing to scale, CC3D is providing an industrial solution to advanced manufacturing techniques of mid to large scale. page 14 u UV+EB Technology • Issue 3, 2016 | 13


RADTECH AWARDS t page 13 PepsiCo Seeking to lower its carbon foot print, Pepsico is looking to EBflexo inks as a replacement for the use of solvent-based materials for snack food packaging. Technological developments around EB ink chemistry are creating stunning advances in print quality and aesthetics. Pepsico reports the use of EB technology reduces VOC emissions as much as 90%, with lower energy consumption when compared to conventional thermal drying. EB is considered “food friendly,” which enables Pepsi to make attractive, environmentally compliant packaging that is cost neutral when compared to incumbent solvent and thermal drying technologies. Cleveland Steel Container Cleveland Steel container has developed the first commercial inline EB and UV process for rigid steel coil substrates in the manufacture of steel pails. CSC is the largest steel pail manufacturer in North America, with uses ranging from hazardous materials to cosmetics. CSC applies and cures EB and UV directly to steel coil for 5-gallon pail lids and bottoms. Beyond a dramatic reduction in energy requirements, CSC reports that since “EB coatings are 100% solids formulations, it means no loss of evaporated solvent from the applied coating. It also means less coating usage and required storage area compared to solvent systems.” Wavefront In a very innovative use of UV curing, Wavefront makes state of the art holographic films using advanced roll-to-roll continuous UV casting lines to manufacture nano/micro structure embossed films on a variety of film substrates. This capability allows WFT to manufacture micro-structures from 200 nanometers up to 150 microns. These unique structures can only be achieved using the latest UV curing and formulating technologies. HRL Laboratories LLC The HRL team demonstrated the first ever UV additive manufacturing of polymer-derived ceramics. By formulating preceramic UV-curable polymers, the team at HRL demonstrated the first-ever additive manufacturing of fully dense, binder-less ceramics, published in the 1/2016 issue of Science. Potential applications for this novel technology include turbine engine components, hypersonic vehicle structures, MEMS devices and electronics packaging. NOVAGARD Solutions Novagard has developed the first industrial UV LED PSA installation on a coating line. Novagard converted a water-based PSA to a UV LED-curable PSA and now is using it to produce PVC foam rolls (more commonly known as weather stripping). The system consists of two 62" wide banks of UV LED curing systems. Conventional UV lamps could not be used as they delivered too much heat to the substrate causing damage. UV LED was the only viable solution, allowing Novagard to pursue new market opportunities. 14 | UV+EB Technology • Issue 3, 2016

Carbon 3D Carbon’s vision is “a future fabricated with light, where traceable, final-quality parts are produced at scale with CLIP technology.” CLIP – Continuous Liquid Interface Production – makes this possible by combining engineering-grade materials with exceptional resolution and surface finish. CLIP eliminates the shortcomings of conventional 3D printing by more rapidly producing objects. “From everyday products like tennis shoes and electronics to industrial components to highly customizable medical devices, CLIP makes it possible for creators to design the parts and products of the future.” City of Cleveland The City of Cleveland, including Cleveland’s Progressive Field ballpark, home of the Major League Cleveland Indians, was recognized for its exploration and use of UV-curable materials as a contribution to environmental sustainability in Cleveland. The city has found UV technology solutions to long-standing issues for protection against corrosion and to provide superior protection for metals, concrete, stones and other substrates in an efficient and fast curing manner. RadTech Announces New “Accelerator Award” In recognition of the increasing interest in the development of sustainable new materials and processes, RadTech now offers an “Accelerator” award to recognize innovative ideas and start-ups. The goal of RadTech is to recognize and publicize the work of new ventures. The inaugural award winner is Poly6 Technologies. Poly6 turns citrus rinds into bio-based materials, called Citrene™. This start-up is introducing clean and sustainable materials for use in performance applications. Citrene™ has gained traction in various industries due to its unique combination of performance, process ability and sustainability advantages, offering enhanced performance, natural materials, throughput benefits and low GHG emissions – all enabled by UV/EB technology. n

Keith Heron and Matt Stellmaker, company founders of Poly6 Technologies, receive the Accelerator Award from Mike Idacavage. uvebtechnology.com + radtech.org


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PACKAGING RESINS By Paul Share, senior product development scientist, printing and packaging, BASF Corporation

Recent Advances in Low Viscosity, Low Migration, Fast Curing UV/EB Resin Technology Background everal critical issues drive technological developments in UV/EB resin technology today, particularly within the fast-growing area of food packaging1. These are summarized in Figure 1.

S

High functionality resins are often used to address the need for higher cure speeds to meet the requirements for higher flexographic press speeds and corresponding improved efficiency and economics. Higher functionality often results in shrinkage, loss of flexibility and poor adhesion to film2. Lower oligomeric resin viscosity is preferred to the use of low functionality, low molecular weight monomers to reduce the total migration of a formulation. The combination of high functionality with high molecular weight in a resin can result in a reduced probability of migration, but it also can result in high viscosity, requiring the use of monomers to achieve desired formulation Viscosity vs. Molecular Weight additional of UV Acrylates (circle size isaproportional to cureviscosity. energy). The dicated by HRLV (high reactivity/low viscosity). The relationships between cure energy, viscosity and molecular weight for a wide range of UV monomers and oligomers are shown in Figure 2.3Advances in Low Viscosity, Low Migration, Fast Curing UV/EB Resin Recent

Epoxy acrylates,polyesters ethoxylates,and propoxylates, urethanes, polyesters andShare, amine modified acrylates are included. Dr.are Paul BASF Corporation lates, ethoxylates, propoxylates, urethanes, amine modified acrylates Although monomer diluents are present in some of the resin systems, there is a clear trend of increasing lthough monomer diluents are present in some of the resin systems, there is a clear trend of viscosity and cure speed with increasing molecular weight. It also is apparent that the lowest viscosity and viscosity and cure speed with increasing molecular weight. It also is apparent that the lowest lowest molecular weight resins have some of the slowest cure speeds. Other systems, which are blends of nd lowest molecular weight resins have some of the slowest cure speeds. Other systems, inert resins with monomers, have the expected high molecular weight and high viscosity combined with low Background blends of inert resins with monomers, have the expected high molecular weight and high curing speed. ombined with low curing speed. Several critical issues drive technological developments in UV/EB resin technology today The viscosity/MW trend is consistent with the area Mark-Houwink equation,1which describes the relationship within the fast-growing of food packaging . These are summarized in Figure 1. ty/MW trend is consistent with the Mark-Houwink equation, which describes the relationship 4 between the intrinsic viscosity Ρ and the viscosity averaged molecular weight M . v e intrinsic viscosity Ρ and the viscosity averaged molecular weight Mv. 4 ďż˝đ?‘Łđ?‘Łđ?‘Łđ?‘Łđ?›źđ?›źđ?›źđ?›ź [đ?œ‚đ?œ‚đ?œ‚đ?œ‚] = đ??žđ??žđ??žđ??žđ?‘€đ?‘€đ?‘€đ?‘€

pend on the specific polymer and conditions and, therefore, the slope of log Ρ vs log Mv will K and Îą depend on the specific the details of the resin chemistry, but there is a general polymer and conditions. The proportionality. For linear polymers, Îą 0.5 to 0.8. The viscosities are slope usually measured and the specific solute-solvent of log Ρ vs log in Msolvent, will v s can influence the value of Îą. depend The đ?œ‚đ?œ‚đ?œ‚đ?œ‚ values in Figure 2 were all measured neat. There is a on the details of the resin chemistry, butathere is a or hyperbranched structure. 5 ption to the typical Îą values, which results from nonlinear general proportionality. For linear polymers, Îą is typically 0.5 to 0.8. The viscosities are usually measured in solvent, and the specific solute-solvent interactions can influence the value of Îą. The values in FIGURE 1. Critical Factors in Food Packaging

16 | UV+EB Technology • Issue 3, 2016

Figure 1. Critical Factors in Food Packaging

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FIGURE 2. Viscosity vs. Molecular Weight of UV Acrylates FIGURE 3. Generalized Dependence of Viscosity upon Figure 3. Generalized Dependence of Viscosity upon Molecular Weight as a6Function of P (circle size is proportional to cure energy). The outlier is Molecular Weight as a Function of Polymer Structure 6 Structure indicated by HRLV (high reactivity/low viscosity).

Figure 2 were all measured neat. There is a noted exception to the In addition to factor of molecular shape, the specific chemical typical Îą values, which results from a nonlinearAs or shown hyperbranched composition of the polymer plays a critical role. In 100 percent schematically in Figure 3, the relationship between molecular weight and viscosi structure.5 UV formulations, just as in solution, the viscosity will be affected highly dependent on molecular structure. Dendrimers, which are very ordered with regard t by hydrogen bonding, the molecular dipole moment and the weight and geometry, have higher viscosity at low molecular weights, which then decrease As shown schematically in Figure 3, the relationship between Hildebrand solubility parameter.8 Therefore, in addition to the increasing molecular weight due to reduced entanglement resulting from their spherical sha molecular weight and viscosity also is highly dependent on dendrimeric/hyperbranched/linear structural effects, the specific addition, low molecular weights the structure of the dendrimers different,the with higher fr molecular structure. Dendrimers, which are very ordered at with building blocks used in the polymer design can is determine 7 Hyperbranched structures are intermediate between linear not contain the core molecule. regard to molecular weight and geometry, have higher viscosity viscosity and reactivity. possessing less order than dendrimers but a lower probability of entanglemen at low molecular weights, which then decrease dendrimeric, with increasing due to a more configuration. This concept is summarized pictorially in Fi molecular weight due to reduced entanglement polymers resulting from Thecompact application of chemistries with dendritic structures in UV/ their spherical shape. In addition, at low molecular weights the EB applications has been investigated for some time.9,10,11 The structure of the dendrimers is different, with higher fractions that challenge for low-migration packaging applications is that do not contain the core molecule.7 Hyperbranched structures high levels of polyether diluents can be necessary to achieve are intermediate between linear and dendrimeric, possessing less fluidity at ambient temperature. Even though the viscosity of the order than dendrimers but a lower probability of entanglement dendrimeric acrylate is much lower than that of the corresponding than linear polymers due to a more compact configuration. This linear acrylate of comparable Mw, the viscosity still is quite concept is summarized pictorially in Figure 4. high, and the dendrimeric backbone often is a solid at room temperature7. This is presumably due to the polarity of the polyester backbone, which comprises the dendrimeric polyol as well as the presence of hydrogen bonding.

Low viscosity monomers often are In addition, the increase in functionality also leads to a decrease in necessary to achieve the rheological the rate of double-bond conversion as a result of the Trommsdorff effect.12 If gelation of the reaction mixture occurs prior to properties necessary for flexographic consumption of the double bonds, then there are no property advantages, such as chemical resistance, to result from the applications, but they bring with them Figure 4. Idealized Relationship betweenInPolymer Structure Properties of a added functionality. a study of acrylate and functionalization challenges relating to migration, often 19-functional dendrimeric polyol, the highest conversion rate was In addition to factor offound molecular shape, specific chemical composition of the polymer p to occur at an the acrylate functionalization of 5.7 due to low molecular weightrole. or Inlow 100 percent UV formulations, just as in solution, the viscosity will be affected by hyd bonding, the molecular dipole moment, and the Hildebrand solubility parameter. 8 Therefore Experimental functionality. Raw materials were weighed and blended to produce the formulations reported. Coatings were applied with a wire rod page 18 u

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UV+EB Technology • Issue 3, 2016 | 17


PACKAGING RESINS t page 17

at a film build of 1 mil on Leneta® cards. Ink dispersions were premixed in a high-speed mixer, and then dispersed on a high-speed media mill to a grind of 5 microns or less. Inks were applied to untreated OPP film with a flexo proofer at a film build of 1.8 microns. All samples were cured with a D bulb under ambient conditions. Curing energy was the lowest energy at which a mar-free coating or ink was obtained. The UV FIGURE 4. Idealized Relationship between Polymer Structure and Properties exposure was measured with an EIT™ radiometer model PP2000. Ink adhesion was determined using Scotch™ Brand 610 tape. The relative amount of ink remaining after tape removal was recorded and reported as percent adhesion. Results and discussion Low viscosity monomers often are necessary to achieve the rheological properties necessary for flexographic applications, but they bring with them challenges relating to migration, often due to low molecular weight or low functionality. The higher reactivity resins often bring challenges relating to viscosity, illustrated in Figure 1, as the highest reactivity resins fall on the higher end of both the molecular weight and viscosity scales. The objective is to achieve a balance between reactivity and diluency.

FIGURE 5. Diluency and Reactivity Effects in Common Oligomer Systems (blue bars represent viscosity; red bars represent cure energy)13 TABLE 1. Resins used in Diluency and Reactivity Study Resin

Chemistry

TPGDA

Tripropylene Glycol Diacrylate

TMPTA

Trimethylolpropane Triacrylate

DPHA

Dipentaerythritol Hexaacrylate

To better understand this effect, a study was made of the viscosity and cure energy of a number of resin compositions. One oligomeric system was selected from the broad categories of epoxy, polyester, urethane and polyether acrylates. Each oligomer then was blended with DPHA, TMPTA, TPGDA and HRLV (a novel highreactivity, low-viscosity resin). The results of this study are shown in Figure 5. In all cases, the order of viscosity was determined to be TPGDA < TMPTA < HRLV < DPHA. The order of reactivity (higher cure energy) was measured as HRLV > DPHA > TMPTA > TPGDA. These resins are summarized in Table 1. In Figure 2, the data point corresponding to HRLV has a molecular weight of 1200 amu and a viscosity of 500 mPas. Based on the earlier analysis of the Mark-Houwink equation, this resin would be expected to assume a more spherical configuration, which may also be a factor in the higher cure speed of blends that contain HRLV. page 20 u

18 | UV+EB Technology • Issue 3, 2016

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TM


PACKAGING RESINS t page 18 TABLE 2. Formulations Used in Evaluation of Flexo Ink Properties Dispersion

Dispersion Letdown

Component

%

Component

%

Resin

60-80

Dispersion

50

2-4

Epoxy Acrylate

15-25

20-40

EOTMPTA

15-25

PI Blend

7.5-10

HMWD

15

Pigment

FIGURE 6. Color Density of Flexo Ink Formulations16

Despite the differences in polarity and intermolecular interactions within the classes of oligomeric resins in Figure 2, the variation in viscosity and cure speed by addition of the diluent resins follows a consistent trend. Dispersing additives with spherical structures have been shown to be effective in pigment stabilization in reactive systems14. If the HRLV resin assumes a spherical configuration, then it also may have properties in pigmented systems that are different from those of conventional linear polymers. To evaluate this idea, flexo inks were prepared from cyan, magenta, yellow and black pigments and tested for cure, color density and adhesion. The test formulations are shown in Table 2, and the results of this study are shown in Figures 6 and 7. Although there are variations across pigments, some clear trends are shown. The two polyester oligomers yield inks with similar color densities and cure speeds. The HRLV resin, presumably with a more spherical rather than linear structure, provides color densities and cure speeds that are superior to the linear polyesters, with the exception of the yellow ink, where the performance is the same. All formulations utilized the same HMWD, and it may be that that the threecomponent system of oligomer, pigment and HMWD could be further optimized in combination with specific pigment chemistries. What is clear, however, is that through the controlled use of the three-dimensional resin structure, differentiation in ink cure speed and color density can be obtained. With sufficient photoinitiator loading, a leveling effect can occur, masking differences in formulation reactivities. This comes at a higher overall formulation cost, since the photoinitiator level is not optimized. To determine whether this played a role in the flexo ink performance, the photoinitiator levels in the flexo ink formulations were reduced by 25 percent, and the cure energies were reevaluated. The results of this experiment are shown in Figure 8. At the lower photoinitiator level, the differences in cure energy between the HRLV inks and the two polyester inks are apparent. It would require the addition of almost 25 percent more photoinitiator to the polyester formulations to approach the cure energy of the HRLV inks.

FIGURE 7. Cure Energy of Ink Formulations17

20 | UV+EB Technology â&#x20AC;˘ Issue 3, 2016

The idealized nonlinear resin structure has low free volume, and therefore the density increase and volume reduction that occur during the crosslinking process will be smaller than for an idealized linear resin. The smaller change in density between the liquid and cured uvebtechnology.com + radtech.org


ink also can be accompanied by an increase in adhesion to films, as compared to that of a linear resin, due to the reduced shrinkage and stress. Although a number of variables, including surface energy, affect adhesion, shrinkage is a significant factor. The adhesion properties of the ink systems are shown in Figure 9.

There are clear differences in the adhesion properties between ink systems shown in Figure 9 which do not parallel the trends that are typically seen in the cure of linear polymers. A slower curing system might be expected to have higher film adhesion due to reduced film stress, and a faster curing system would be expected to have lower film adhesion to due increased film stress. These results show that the structure and properties of the HRLV not only increase cure speed but also increase OPP film adhesion compared to linear polyester oligomers. Conclusions The viscosity and molecular weight relationship of commercial UV resins has been examined through the lens of the Mark-Houwink equation to better understand the effect of molecular shape on coating and ink performance properties. An HRLV resin, which was predicted to have a nonlinear configuration on this basis, was evaluated for diluency, color density, cure energy

FIGURE 8. Effect of Photoinitiator Level on Flexo Ink Cure Speeds

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UV+EB Technology â&#x20AC;˘ Issue 3, 2016 | 21


PACKAGING RESINS t page 21 11. James, D.; Bernquist, H.; Appleqvist, P.; Sandell, P.; Sörenson, K., RadTech 2006 Technical Proceedings. 12. Tulig, T.; Tirrell, M. Macromolecules 1982, 15, 459. 13. Formulations contain a blend of 30% diluent with 66% oligomer and 4% Irgacure™ 500. Numerical values over the polyether data represent viscosity and are added for clarity. 14. Rudolfi, A.; Krohnen, M.; Piestert, F.; Möβmer, S., European Coatings Journal, 11, 2013, p. 22. 15. HMWD (high molecular weight dispersant). 16. Inks applied to OPP at 1.8µ film thickness and formulated to 1000 mPas viscosity. Pigment levels of cyan, magenta, yellow and black inks are 15.0%, 12.3%, 10%, and 12.5%, respectively. 17. Samples cured with D bulb at 1.8µ film thickness.

FIGURE 9. Adhesion Properties of Ink Formulations on Untreated OPP as a Function of Photoinitiator Level and film adhesion properties in flexo ink formulations. In comparison to conventional polyester resins at the same formulation levels, flexo ink formulations containing the HRLV resin provided lower cure energy, higher color density and better adhesion to untreated OPP film. In terms of the structure/property relations discussed, HRLV has the high reactivity that would be expected for a highly functional resin but does not have the high viscosity which is associated with highly functional linear resins. HRLV has the superior adhesion associated with the low free volume spherical resin structure but does not have the high viscosity and need for polyether diluents that can be required for dendrimeric structures. In addition to low viscosity, HRLV has the molecular weight and functionality that make it suitable for low-migration packaging applications. n Acknowledgements The author would like to thank Dr. Sebastian Berger, Dr. David Tuerp, Stephen Godlew, and William Merritt for their contributions to this work. References 1. “The Future of Package Printing to 2015,” Pira International Ltd. 2.

Chiang, T.H.; Hsieh, T.E., Intl. Journal of Adhesion and Adhesives, 26, 2006, p. 520.

3.

Data obtained from BASF Laromer™ Product Literature.

4.

“Introduction to Polymers,” R. J. Young and P.A. Lovell, 1991, pp 196-198.

5.

Gorodetskaya, I.A.; Choi, T.; Grubbs, R.L., J. Am. Chem. Soc. 129, 42, 2007, p.12672.

6.

Jikei, M,; Kakimoto, M. Prog. Polym. Sci. 26, 2001, p. 1233.

7.

Zagar, E.; Zigon, M. Prog. Polym. Sci. 36, 2011, p. 53.

8.

Miller-Chou, B.A. ; Koening, J.L. Prog. Polym. Sci. 28, 2003, p. 1223.

9.

Klang, J. Radtech Technical Proceedings, 2006.

Leneta® is a trademark of Leneta Company, Inc. EIT® is a trademark of Electronic Instrumentation and Technology LLC. Scotch™ Brand 610 tape is a registered trademark of 3M. IRGACURE® is trademark of BASF SE. ® Registered trademarks of BASF Group. © 2016 BASF Corporation

Dr. Paul Share is senior product development scientist, Printing & Packaging, for BASF. Share received his B.S. in Chemistry at the University of Chicago and his Ph.D. in Organic Chemistry at the University of California Berkeley. He then did postdoctoral work at the Max Planck Institut for Quantenoptik in Garching, Germany and at the University of Pennsylvania, working in the area of organic photochemistry and photophysics. With previous positions at Henkel and Valspar, Share joined BASF in 2011, where he is responsible for global UV/EB resin development for printing and packaging applications.

10. Sangermano, M., Radtech Report, 3, 2012.

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Technology Showcase MultiWave LED-UV™ Creates Blended Wavelength Modules Air Motion Systems, Inc., River Falls, Wisconsin, created a blended wavelength series LED module called MultiWave LED-UV™. It features the industry’s first uniform blend of Wide Spectrum UV and LED wavelengths at equivalent power levels. Its performance range is designed for compatibility with many existing UV photo initiator packages, including low-migration formulas. The development means that the ink prices for LED curing now can be similar to those of existing high-quality UV inks. MultiWave LED modules give printers and converters wider spectrum compatibility with UV inks, varnishes and coatings combined with all the advantages of 100 percent LED-based curing, including low energy consumption, elimination of mercury and ozone, removal of heat, improved curing consistency, safer operation and elimination of frequent bulb changes. MultiWave LED modules are based on the latest high-efficiency (HE), upgradeable diode chipsets from AMS and will be offered in power densities of 12W, 17W and 25W classes, consistent with existing power setups offered by AMS, and capable of reaching the highest production speeds in perfecting and straight mode of machines on the market today. For more information, visit www.airmotionsystems.com. Roland DG Introduces Addition to UV LED Flatbed Printer Series Roland DG, Irvine, California, recently added the VersaUV LEF-300 to its lineup of benchtop UV LED flatbed inkjet printers. The LEF-300’s printing area has been expanded to 770x330 mm, 50 percent more than the previous models. The LEF-300 can print CMYK plus white and clear UV ink on a vast array of substrates, including PET, ABS and polycarbonate; soft materials such as TPU and leather; and 3D items, including pens, smartphone cases, signs, personalized awards, giftware, promotional items, laptop covers and more. A vacuum table makes it easy to hold thin and soft materials in place. With four print heads and two UV LED lamps, the LEF300 is approximately 60 percent faster than the LEF-20. The number of white and clear (gloss) ink nozzles have been doubled for faster printing, increased density and opacity and faster buildup of multiple layers for 3D textures. A draft print mode enables quick prototype prints. For more information, visit www.rolanddg. com. Honle Offers New LED Powerline Honle UV America, Inc., Marlboro, Massachusetts, launched the LED Powerline 76/120 – a high-performance array for intermediate and final curing for printing applications. Other applications include curing of varnishes, UV-reactive adhesives and pottings. The LED unit is available in wavelengths of 365, 24 | UV+EB Technology • Issue 3, 2016

375, 385, 395 and 405 nm. With its low weight and small dimension, the LED Powerline can be integrated into the smallest interspaces. The water-cooled unit is appropriate for being used in a cleanroom. For more information, visit www.HonleUV.com Ushio Unveils Unijet UV LED Series Ushio America, Inc., Cypress, California, unveiled the Unijet UV LED series. It consists of LED light sources that are designed and developed to satisfy the demands that are involved in UV curing and printing and is ideal for individuals seeking an alternative to standard lamp-based UV light sources. Ushio’s varied, custom designs, in the forms of the M, L, I, E and A-Series, are developed around the unique functions of the numerous applications in the commercial and industrial UV curing and printing industries. Features include water-cooling, air-cooling and dimming. These Unijet LED modules are safe to operate and the design offers energy savings while also allowing for high peak irradiance, stability and consistent uniformity. It has a compact design and an operating life of greater than 10,000 hours. For more information, visit www.ushio.com. Dymax Introduces Multi-Cure Conformal Coating Dymax, Torrington, Connecticut, announced the release of its newest conformal coating – Multi-Cure 9451. This true black material – a single-component, 100-percent solids, light- and heat-curable conformal coating – is designed to enhance security on PCBs. In addition to its ability to improve circuit reliability in harsh conditions, its opaque black color is intended to cover markings, labeling and other identification, as well as sensitive information on the circuit board. Formulated with a secondary heat cure, 9451 typically can be applied and cured at up to 5mils thick, in one pass, for applications where shadow areas exist. It becomes immediately tack free after curing and can be applied to a variety of substrates, including glass-reinforced epoxy laminates, glass and stainless steel with a good bond. This product is in full compliance with RoHS directives 2002/95/EC and 2003/11/EC. For more information, call 860.482.1010 or visit www.dymax.com. Baldwin Launches LED UV Technology for All Printing Applications Headquartered in St. Louis, Missouri, Baldwin Technology Company, Inc. launched its new ultra-compact modular LED UV single- and multi-frequency (Broadband UV) system, the uvebtechnology.com + radtech.org


UVed™ Flex. It is suitable for ink jet, web, flexo and litho applications and allows conventional UV chemistries in many applications. Its patented interchangeable UV lens technology ensures optimized pure UV performance at the ink/coating surface. Baldwin’s new multi-frequency LED UV system allows some conventional chemistry to be used without any modification, while the single frequency LED UV works with compatible LED inks and coatings now on the market. LED UV offers economic performance with minimal energy consumption, no heating of the substrate, high color definition, ability to print on any material, no need for powder spray, no set off worries and immediate processing. For more information, visit www.baldwintech.com. Heraeus Announces Plug and Play UV LED Curing Heraeus Noblelight America LLC, Hanau, Germany, introduced Semray®, the UV LED plug and play solution for curing processes. Semray® has special micro-optics that reduce the stray light to a minimum, and it can be used with different machine widths and working distances. With the plug and play principle, the exchange of single segments is faster, which minimizes downtime and increases productivity. Semray® also makes retrofit and upgrade easy and improves performance with its materials and unique LED technology. For more information, visit www. heraeus.com. Enercon Offers Blown Ion Plasma Treater Blown ion plasma technology from Enercon Industries, Menomonee Falls, Wisconsin, delivers effective treatment for both conductive and nonconductive surfaces prior to bonding with inks, coatings and adhesives. Enercon plasma treaters bombard surfaces with a high-speed discharge of ions to clean, etch and functionalize surfaces. Its focused treatment works well with flat surfaces and hard-to-reach recesses. Models are available with either one or two treatment heads in both standard and Pro Series configurations. The treaters feature a fully enclosed steel body construction. They also have a compact footprint, reliable industrial design and USB data drive. For more information, visit www.enerconind.com. LED Specialists Unveil Curing Engine LED Specialists, Holbrook, New York, unveiled its LS0151 UV

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UV+EB Technology • Issue 3, 2016 | 25


Technology Showcase t page 25 LED Irradiator as the LED “cure” for mercury-based lamps. The LS0151 curing engine is an industrial grade, air-cooled UV curing system that delivers a precisely controlled, evenly distributed irradiance field ideally suited to conveyor applications that include hydrogel, adhesives, coatings, medical devices, electronics and optoelectronics. Adjustable irradiance power controller and system enclosure are optional features. For more information, visit www.ledspecialists.com. GEW Launches Air-Cooled LED UV Lamphead GEW, West Sussex, UK, introduced a fully air-cooled LED UV lamphead, LA1. The enhanced airflow design ensures effective heat dissipation at high power levels. The LA1 is built around the same proven cassette-based design as the E2C and LW1 lampheads and is fully compatible with existing ArcLED systems without the need for external chillers, pipes, coolant or any other modification. The LA1 is able to perform without the heavy infrastructure and maintenance required by water-cooled LEDs while enjoying the benefits of the efficiency, reliability and extended life cycles of LEDs. For more information, visit www. gewuv.com. Excelitas Technologies Introduces OmniCure Series Excelitas Technolgoies Corporation, Waltham, Massachusetts, introduced the OmniCure® LX500 UV LED spot curing system and OmniCure® AC5 Series UV LED systems. The LX500 is available in either two or four LED head system configuration with up to 16 W/cm2 peak irradiance. It provides optical stability +/- 5 percent via Intelli-Lamp® LED technology for repeatable device assembly and reduced costs. OmniCure LX500 is ideal for use in medical devices such as catheters, cannulas, endoscopes and syringes; electronics such as OPU, smartphones and tablets; and general-purpose, small-component applications such as bonding and coatings. Additionally, the AC550/P and AC575/P air-cooled UV LED curing systems provide high irradiance (14 W/cm2), enabling manufacturers to achieve high productivity. The LEDs deliver long lifetime and lower electrical consumption to reduce running costs. OmniCure AC5 Series Systems are designed to cure inks, adhesives and coatings in print, industrial and electronics manufacturing applications. For more information, visit www.excelitas.com/OmniCure. Sun Chemical Expands High Chroma Dispersions Portfolio Sun Chemical Performance Pigments, Cincinnati, Ohio, expanded its portfolio of high chroma dispersions for energy-curable inkjet inks to now include particle sizes that are smaller than 150 nm (micron). The smaller particle sizes increase the strength and color gamut allowing for bolder color and more hues, while maintaining particle size stability and ink filtration. Previously branded as SpectraRAY® IJ dispersions, Sun Chemical now will market the product line under the Jetsperse® UV brand name. The rebranded Jetsperse UV for energy-curable inkjet inks naturally fit with Sun Chemical’s Jetsperse family of dispersions for inkjet. Jetsperse UV delivers formulators maximum flexibility 26 | UV+EB Technology • Issue 3, 2016

in their formulations and is provided in full color sets for both propoxylated neopentyl glycol diacrylate (PO-NPGDA) and 2-phenoxyethyl acrylate (2-PEA) monomers. For more information, visit www.sunchemical.com. Siegwerk Presents New Range of Sustainable Inks Siegwerk, Siegberg, Germany, unveiled UniXYL, a new ink range, incorporating renewable, forestry-based components for water-based flexographic printing applications. They are characterized by low VOC (volatile organic compounds) emissions and lack of flammability, making it easier to comply with relevant regulations. The bio-based resin contained in UniXYL inks is obtained from lignocellulosic bio-mass, which is available in particular in feedstocks from forestry. Siegwerk produces its water-based and eco-friendly inks in a dedicated laboratory at its Technical Center in Annemasse (France). The new UniXYL ink range was developed by Siegwerk’s “Global Innovation Network,” the company’s in-house research network, which is tasked with increasing the share of plant-based raw materials in all Siegwerk products. For more information, visit www.siegwerk.com. KBA-Flexotecnica Introduces Fully Hybrid Machine KBA-Flexotecnica, Tavazzano (Lodi), Italy, a member of the Koenig & Bauer Group (KBA), introduced its new CI flexo NEO XD LR HYBRID. It is engineered for printing with solvent- and water-based inks, as well as curing ink systems such as UV LED and EB. With up to 12 colors, a cut-off from 4001,200 mm, a maximum web width of 1,650 mm and a maximum printing speed of up to 500 m/min, in terms of automation and operation this press meets various production demands in flexible packaging. It embodies the latest features found on the new generation of the “X” EVO XD and EVO XG series from KBAFlexotecnica. These include solutions aimed at assuring added productivity even with the shortest of print runs, excellent print quality and the eco-friendliness of the converting process. For more information, visit www.kba-flexotecnica.com/en n

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EB CROSS-LINKING By Im Rangwalla, market development manager, Energy Sciences Inc.

Electron Beam CrossLinking of Polyolefin Films for Various Packaging Applications Abstract adiation cross-linking comprised of gamma rays from a Co60 source and even high-energy electron crosslinking from > 1 MeV accelerators have been commercial since 1960s. These applications were mostly for the wire and cable industry, rubber tires and some high-barrier shrink film applications for meat packaging introduced by Cryovac. Since the development of low-voltage electron beam accelerators in the range of less than 300 kV – in particular in the 125 kV range – EB cross-linking has found new applications and markets, particularly in the packaging industry. This report will discuss these markets, along with the properties achieved by electron beam irradiation of polyolefin films used in packaging. In addition, theory of electron beam cross-linking will be discussed in detail.

R

Introduction When irradiated either by gamma rays from a Co60 source or high-energy electrons generated by electron accelerators, polymers either cross-link or undergo chain scission, depending on the chemical structure. Both processes take place simultaneously and, depending on the chemical structure, either cross-linking or chain scission becomes the rate-limiting step and the end result of the irradiated polymer. Cross-linking usually results in molecular weight increase and is directly proportional to the dose of irradiation. The molecular weight increases with dose until a three-dimensional network is formed, making the polymer thermoset. TABLE 1. Predominant Processes in Some Irradiated Polymers Cross-Linking

Chain-Scission

Polyethylene

Polyisobutylene

Polystyrene

Polypropylene

Natural Rubber

Polyvinylidene chloride

Polyvinyl chloride

Polytetrafluoroethylene (TEFLON)

Polyamides

Cellulose (Paper)

TABLE 2. Effect of Irradiation on Properties of Oriented Polyethylene Irradiated

Not Irradiated

0.916

0.916

At 22° C

8000-16000

1500-3000

At 93° C

1500-3000

100-200

Specific Gravity gm/cc Tensile Strength psi

% Elongation

100-200

600

Heat Seal Range °C

150-300

110-150

% Shrinkage 98° C

80

60

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When chain scission reaction predominates, then the molecular weight decreases with dose, resulting in reduction of the polymer’s mechanical properties. Table 1 indicates which polymers cross-link or undergo chain scission. 1 Radiation cross-linking of natural rubber for the tire industry and cross-linking of polyethylene for packaging have been used since the 1960s, using high-voltage 400 kV to 1 MeV type EB accelerators. Even for the wire and cable industry, radiation cross-linking to provide temperature page 28 u

UV+EB Technology • Issue 3, 2016 | 27


EB CROSS-LINKING t page 27

FIGURE 1. Process of Biaxially Orienting EB Irradiated Polyethylene Film 2A

2B

2C

FIGURES 2A, 2B AND 2C. Electron Beam Cross-linking of Polyethylene Mechanism resistance was the favored curing option over thermal crosslinking using peroxides.

significant enhanced physical properties required for heavy-duty high-shrink bags for meat/poultry packaging.

Significant research and commercial activity in radiation crosslinking of polyolefins has occurred, especially focused on polyethylene films for packaging applications. Properties of ordinary polyethylene film made by the bubble process were significantly enhanced by electron cross-linking, as shown in Table 2.2 As can be seen in the table, EB irradiation provides

The process is shown in Figure 1. The extruded thick-walled tube is irradiated using a high-energy 1 MeV type accelerator before being oriented in a bubble form. The irradiation step cross-links the polymer molecules, then it is biaxially stretched and oriented. The irradiation imparts the memory effect to the polymer, resulting in higher shrink ratios. The cross-linking effect

28 | UV+EB Technology â&#x20AC;˘ Issue 3, 2016

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Low-voltage electron beam cross-linking applications High-Barrier Shrink-Film Bags High-barrier shrink bags were introduced to increase product shelf life. These high-barrier shrink bags containing three layers of film were manufactured by the double bubble process3 as shown in Figure 3. These layers contained PVDC (polyvinylidene copolymer) typically having the following structure: Outer Layer = 48 microns (18% EVA + LDPE) Middle Layer = 7 microns (PVDC) Inner Layer = 8 microns (18% EVA + LDPE)

FIGURE 3. High-Barrier Shrink-Film Bag Double Bubble Process, Using Three Layers

After the second bubble, the wall thickness is typically around 63 micrometers. The PVDC layer provides the required oxygen barrier properties, oxygen transmission rates of 8 to 10 cc/m2/24. EB cross-linking is required to increase the outer layer heatresistance to avoid burn-through, at the same time restrict EB absorbance to the PVDC layer and the inner sealant layer. EB irradiation to PVDC causes discoloration, and EB irradiation to the inner sealant layer causes cross-linking and increases its melt index, thus reducing seal strength. Neither property is desirable. The efficacy of controlling the depth of electron penetration using low-voltage EB units 4,5 to the outside layer to achieve the desired cross-linking is shown in Figure 4. By operating the EB equipment at 90 to 100 kV and a dose to cure of 4 to 6 Mrads, temperature resistance to the outer (EVA+LDPE) layer is increased to 220°C by cross-linking it. The inside sealant layer is not cross-linked and has a lower melt index, providing the required seal strength. The dose to the PVDC layer also is reduced. Another benefit of EB cross-linking is avoidance of cold shrinkage.

FIGURE 4. Desired Properties with EB Cross-linking using Low-Voltage EB Accelerators increases the molecular weight of the polymer, resulting in higher temperature-resistance, broader heat-seal range and enhanced mechanical properties, as shown in Table 2. Copolymerizing of EVA copolymers and EB cross-linking results in excellent shrink bags. Electron beam cross-linking has two major advantages over other methods: FDA approval and lack of residual chemical contaminants. As a result, greater than 90% of frozen turkey is packaged in high-barrier EB cross-linked PE films. EB cross-linking of polyethylene chemistry Upon absorbing the electrons, polyethylene molecules form free radicals. These free radicals are postulated to be formed on adjacent chains, accompanied by the loss of hydrogen molecules, known as the hydrogen abstraction process. Hydrogen gas is liberated upon cross-linking, and the polymer radicals combine readily to form a three-dimensional network, as shown in Figures 2A, 2B and 2C. uvebtechnology.com + radtech.org

Utilizing split rollers, one EB unit can be used to simultaneously irradiate both sides of the shrink bags. For example, a 26-inchwide shrink bag goes into the EB for irradiation on the bag’s top layer. The bag comes out, goes over the turn bar for irradiation on the other side and is wound up. A 54-inch low-voltage EB unit is commonly used for this application. High-Barrier Skin Packaging The use of high-barrier skin packaging is already common in Europe and gaining market acceptance in North America. Meats, cheese, poultry and seafood products are commonly packaged this way. The high-vacuum barrier film settles around the product like a skin without compromising the product structure. It provides the required safe and secure seal, preventing contamination and leakage, at the same time maintaining the natural appearance of the food product. The materials of the skin film are designed to seal various types of trays. The skin films are typically 80 to 150 microns thick, with the bulk of the market requiring 100 microns. page 30 u UV+EB Technology • Issue 3, 2016 | 29


EB CROSS-LINKING t page 29 The structure of the film is as follows: Typically 100 microns (100 grams/m2) (5 layers) Surlyn Ionomer Tie Layer EVOH 44% Tie Layer Inside Sealant layer (LDPE/EVA)

Ethylene vinyl alcohol (EVOH) provides the required oxygen barrier typically of < 10/cc/m2/24 hrs to provide shelf stability and avoid meat rancidity from oxygen contamination. Low-voltage electron beam cross-linking of the outer ionomer layer provides the required temperature resistance of > 200° C to the ionomer. This layer is in direct contact with the heating surface, while the inside sealant layer is not EB-treated and hermetically seals to the tray at a lower temperature. Low-voltage 125 kV operation of the EB unit restricts penetration to the inside sealant layer (DD125kV), providing essentially no dose to the sealant layer, as shown in Figure 6.

120.0

DOSE % FRONT SURFACE

100.0 80.0

Nonbarrier shrink films for packaging This application usually is a three-layer structure of lldpe/lldpe/ lldpe. The thickness of these films is in the range of 12 to 18 microns, and the typical application is shrink films for packaging. EB treatment using low voltage provides better shrink properties and temperature-resistance to avoid burn-through.

60.0 40.0 20.0

Conclusion Use is increasing for low-voltage electron beam processes (less than 125 kV operating range) to cross-link polyethylene-based FIGURE 6. Depth Dose 125 kV films for packaging applications. When high-barrier packaging is required for shrink bags or skin packaging, electron beam cross-linking provides advantages, including longer shelf life to Nonbarrier shrink films for packaging: reduce waste. Sustainable packaging, with a mandate for lower This application usually is a three-layer structure of lldpe/lldpe/lldpe. The thickness of these films is in energy consumption, is paving the path for use of these smaller, the range of 12 to 18 microns, and the typical application is shrink films for packaging as shown in Figure 7. EB treatment using low voltage provides better shrink properties and temperature-resistance to avoid energy-efficient electron beam accelerators. Moving forward, burn-through. use of EB technology either to cross-link film or initiate in situ polymerization for packaging will grow. n 0.0

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20

40

60

80 100 RANGE GRAM \M2

120

140

160

What is a Seven Letter Word for Performance, Innovation, and Service?

Servicing the energy cured coatings Industry with unique and reactive silicone building blocks Figure: 7 Non-Barrier Shrink Films for Packaging

Your Technology Siltech Chemistry

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References 1. “Radiation Chemistry of Monomers Polymers and Plastics.” Joseph Wilson, Professor of Chemistry, Bishop College. Marcel Decker Inc., New York, 1974. 2.

“Plastic Films for Packaging.” Technology Applications and Process Economics. Calvin J. Benning, Technomic Publishing Inc., 1983.

3.

US Patent 56746707 A. Publication date October 7, 1997. Henry G. Schirmer, W.R. Grace and Company, Connecticut.

4.

US Patent 6426507. Filed November 5, 1999. Rangwalla, Imtiaz J. Energy Sciences Inc.

5.

US Patent 6610376 Filed November 30, 2000, Rangwalla, Imtiaz J. Energy Sciences Inc.

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Optimum Performance Excellent Customer Service Innovative and Customized Products

Siltech Corporation

225 Wicksteed Avenue; Toronto, Ontario, Canada M4H 1G5 Tel: (416) 424-4567; Fax: (416) 424-3158

www.siltech.com

30 | UV+EB Technology • Issue 3, 2016

Imtiaz (Im) Rangwalla has over 25 years of experience in EB processing, especially applications of EB for packaging applications. He has presented and published several papers at various conferences on EB processing and also has several patents in that field. Currently, Rangwalla works in the sales and marketing group for Energy Sciences, Inc. as a market development manager. He has a Bachelor’s degree in Chemistry and Chemical Engineering and a Masters in Chemical Engineering from Northeastern University. uvebtechnology.com + radtech.org


PACKAGE PRINTING OUTLOOK By David A. Biro and Jim Bishop, Sun Chemical, USA

Advances in Electron Beam Curing in Wide Web Flexible Package Printing Abstract lectron beam (EB) curing for wide web flexible package printing continues to evolve. Flexographic ink systems have been optimized to allow wet trapping of ink colors cured with a single electron beam unit after the last station in a central-impression press configuration. Long runs with stable printing performance are enabled by new press technology that includes temperature-controlled print stations. Web offset flexible package printing also is attractive given advances in variable repeat press technology. This includes the development of presses with offset print stations arranged in a central impression configuration. A comparison of EB flexo and EB offset printing technology will be presented. Both technologies allow for flexible package printing with near zero VOCs and low migration inks that are well suited for food packaging applications.

E

Introduction Electron beam curing uses the high energy of accelerated electrons to directly cause the cross-linking of inks and coatings (Figure 1). Commonly, acrylate monomers, oligomers and prepolymers are used in many commercial applications. Other chemistries also are commercially available. The high energy of this curing process insures that a high degree of conversion from oligomer to polymer takes place. The use of this actinic radiation occurs under inert atmosphere, such as nitrogen, to reduce ozone and other species generated under ionizing radiation. The non-oxidative atmosphere promotes a high level of cross-linking between the ingredients in the formulation. Increased crosslinking reduces free monomer and oligomer fragments to a level where the cross-linked product is acceptable for food packaging applications. Characteristics of EB curing A few key characteristics of electron beam curing include the following: • Fast curing, up to 400 m/min • Relatively “cold” process (Δ T ~ 5-10oC) • Curing less affected by color or print density • Electrons can penetrate deep into printed structures • Cure inhibited by oxygen, nitrogen inerting required • Cure under nitrogen reduces odor potential • Ideally suited to web processes • Wet-on-wet printing with a single curing unit at end of press Some advantages of electron beam curing consist of the following: • Electronically controlled dose rates – GMP/Assurance of cure • Cured product exits the process ‘sterile’ • No photoinitiators • Lower energy consumption • Low heat (IR) radiation on substrate or central impression cylinder • Low maintenance means less down FIGURE 1. time page 32 u uvebtechnology.com + radtech.org

Vacuum Chamber Repeller (80–125 kV to >300kV) Filament Titanium Foil Window Electron beam (Radiation dose 25 – 30+ kGy)

Inert Atmosphere Coating / Ink Substrate

UV+EB Technology • Issue 3, 2016 | 31


PACKAGE PRINTING OUTLOOK t page 31

• Conventional Flexo

• EB Flexo Technologies

Overhead Oven

Interstation Dryer

FIGURE 2. Conventional Flexo vs. EB Flexo Technology While some disadvantages are comprised primarily around the influence on the substrate, such as: • Discoloration of some polyamide(PA), PVC, OPP formulations • For PE, the heat seal temperature of the thermoplastic can be increased. • For OPP, the hot tack window could be altered. • Some plastic films may be subject to chemical breakdown products under electron beam radiation. • Some chlorinated substrates suffer from odor effects. • Electron beam installations require a higher investment cost, but less maintenance and lower operating costs balance out the equation. EB offset Electron beam curing on lithographic offset presses has been around for about 30 years, predominately for folding carton and multiwall aseptic packaging applications. The applications are roll-to-roll or roll-to-diecut applications. The application is weton-wet lithographic printing, similar to conventional web offset heatset or conventional sheet fed printing, except that the inks and coatings are curing via electron beam rather than heat or oxidative drying. There is no interstation curing (although some presses have one to two UV curing units at the front of the press to perform additional converting). The substrate tension control can be a challenge. Newer inline presses are equipped with variable repeat length designs, such as variable sleeves, to accommodate the requirements needed for the flexible packaging printing market. One new central impression (CI) offset press is the first one of its kind to use the film handling capabilities that are commonplace in solvent flexographic presses. In general, the cost of offset plates is lower than the cost of flexo plates, making lithographic offset electron beam curing an attractive alternative to flexography for the flexible packaging printing market. This has been a growing area since 2006. 32 | UV+EB Technology • Issue 3, 2016

Electron Beam

EB flexography Traditional flexographic printing presses come in three formats: inline, stack and central impression. High-quality graphics on wide web flexible film for food packaging are traditionally associated with large central impression flexo presses. Some printers and converters have modified or removed dryers and replaced them with UV or EB curing units to remain flexible in their operations (Figure 2).

Changing from solvent-based or water-based inks to UV/EB presents challenges; yet, many are interested in the quality and rapid curing of newer technology. Some central impression flexo presses with overhead dryers can be converted to EB flexo by replacing the dryer with an EB curing unit. Other changes, such as ink delivery and web handling, also are possible. This is a wet-on-wet application with no interstation drying. Several suppliers offer a technology with EB curing, and others are offering technologies with and without interstation drying. The benefits are seen in high-quality graphics and chemically resistant inks suitable for high-speed wide web flexible film for food packaging applications. Food packaging applications For applications where extractables or low odors are essential, such as food and drug packaging, this process provides a high margin of safety. Electron beam inks and coatings generally do not contain volatiles, so emission control equipment that is used for water- or solvent-based systems is not necessary. Local regulatory standards should be followed. Although EB inks and coatings can be formulated to have very low extractables, they do not have FDA approval for direct food contact. The products, like many conventional inks, can be used where a barrier exists between them and the food. Despite the above mentioned cautions, electron beam ink curing is used to print on individual juice boxes, citrus juice and milk containing products in the folding carton format. Many are produced on web presses running commercially at 250 to 300 meters/min. For many customers, folding carton applications for food packaging are a large part of the business. The converted board or polycoated board usually is diecut inline using a platen or a rotary diecut device. The latter enables rapid finishing of the product. Several converters print on plastic films or paper/ polyethylene extrusion laminates for products such as in-mold labels, label wrap stock, shrink sleeves or flexible food packaging. Food packaging application requires the use of inks and coatings which are suitable for the type of packaging involved. uvebtechnology.com + radtech.org


Packaging Categories Non sensitive

Non food packaging or functional barrier between food and packaging

Sensitive “indirect”

Food is not in contact with the packaging, but there is no safe barrier between both

Sensitive “direct”

Food is in physical contact with the inner (unprinted) side of the packaging

FIGURE 3. Packaging categories Following are some examples of use today: • Folding carton. Predominantly in the US on boxes for dry foods, cereals, pasta, etc. • Liquid and ice cream packaging. Coated board with EB inks in conjunction with extrusion lamination or UV or EB overprint varnishes • Pet food bags. Multiwall paper bag or film construction for dry pet food (UV & EB) • Shrink sleeve labels. A range of films (PP, PE, PET, PVC, OPS) with reverse-printed EB inks with a gravure applied solvent last down white ink • Wraparound labels. A range of films (PP, PE, PET, PVC, OPS) with surface printed EB inks • In-mold labels, yogurt lidding, cold seal snack food, etc. • Emerging use in short run flexible packaging, surface and reverse printing, including lamination (PP, PET mainly today) Nonsensitive packaging is where the product is not food or there is a functional barrier between the ink and the packaging. Example: multi-wall fruit juice containers, spices or soup package mixes. Sensitive ‘indirect’ packaging is where the food is not in direct contact with the packaging material, but there is no safe barrier between the packaging and food. Cereal or snack food boxes would be examples. Sensitive ‘direct’ involves packaging the food in physical contact with the inner (unprinted) side of the packaging. Examples include orange juice and milk containers, such as gable top polyboard boxes (Figure 3). An understanding of the packaging material and how it is processed is important when considering the effects of ink and coating component migration. The types of migration include the following: 1. Penetration migration. Migration from the printed side through the substrate onto the unprinted side. uvebtechnology.com + radtech.org

2. Contact migration. Migration from the printed side to the unprinted side of another sheet or stack or roll. 3. Evaporation migration. Migration due to the evaporation of volatile materials by heating (heating, cooking or boiling the frozen products in its original packaging. 4. Distillation migration. Migration through steam distillation by baking, cooking or sterilization. The first two forms of migration are the most commonplace. The latter are less common, but the construction of the package and decoration are important so as not to have any negative organoleptic events. Judicious selection of inks and coatings, along with the substrate, is an important cooperative opportunity between suppliers and converters. Understanding the limits of electron beam curing is important when considering flexible package printing. Namely, is the final package printed/coated with wide web EB curing suitable for the down lane converting, filling, packaging, transporting, warehousing, display, consumer handling and storage? These are normative considerations, yet normal in many converted film and carton products for food packaging. This means open dialogue regarding the current state (conventional solvent flexo) of converting vs. an alternative (such as EB flexo or offset). Trends and technology developments Technology developments in energy curing include small electron beam units for narrow web label printing and converting and the use of electron beam curing for ink jet, screen and gravure printing. The shifting marketplace to shorter runs and fast printing is coupled with high-quality graphics. Digital high-speed ink jet and other toner-based digital technologies will be lagging behind the 250 to 300 meter/minute existing EB curing flexible packaging market of today. But, they will catch-up eventually – maybe even with the assistance of electron beam curing. The flexo and gravure wide web presses will not go away. In fact, the flexo /gravure ratios across the globe are USA 80/20, EU 40/60 and Asia 10/90. This technology is used for wide web flexible film printing for common food packing. Electron beam cured litho and flexo are making their way into applications such as common food packaging, high end laminates and lamination-look packages (i.e., using a high gloss coating to replace lamination). There will be more inline electron beam laminate structures as the technology evolves to control bond strength using novel chemistry and electron beam curing. Finally, combination printing with water- and solvent-based technologies (along with the EB litho and EB flexo technologies mentioned above) complement the current state of wide web printing. n

UV+EB Technology • Issue 3, 2016 | 33


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ANNUAL BUYERS GUIDE Products/Services..................................................................................................................... 36 UV/EB Application Equipment......................................................................................... 36 Formulated Products........................................................................................................ 37 Raw Materials.................................................................................................................. 37 Services........................................................................................................................... 38 Manufacturers Directory........................................................................................................... 39

PRODUCTS/SERVICES OFFERED INDEX # 3D Printing/Photopolymers.......... 37

G Glass Optics................................ 38

A Additives...................................... 37 Adhesives & Sealants................. 37

H Hybrid Polymers.......................... 38

C Coatings...................................... 37 Consulting................................... 38 Cure/Dose Measurement............ 36 Curing Lamps.............................. 36 Custom........................................ 37 E Electron Beam............................. 36 Emulsions/Dispersions................ 37

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I Inks.............................................. 37 L LED............................................. 36 Light Stabilizers........................... 38 M Monomers................................... 38 O Oligomers.................................... 38 Overspray Collection................... 36

P Photoinitiators/Sensitizers........... 38 Pigments/Dispersions.................. 38 Pilot Lines.................................... 38 R Reactive Silicones....................... 38 Reflectors.................................... 36 S Surface Preparation.................... 36 T Toll Services................................ 38 U Ultraviolet.................................... 36

UV+EB Technology â&#x20AC;¢ Issue 3, 2016 | 35


PRODUCTS/SERVICES UV/EB APPLICATION EQUIPMENT

Reflectors Newport Thin Film Laboratory, Inc. Porex Corporation

Cure/Dose Measurement Carestream Contract Manufacturing EIT Instrument Markets Gigahertz-Optik Miltec UV Netzsch Instruments North America LLC

Honle UV America

261 Cedar Hill St. Bldg. C Marlboro, MA 01752 Phone: 508-229-7774 Fax: 508-229-8530 Website: HonleUV.com

Excelitas Technologies OmniCure® UV Curing Solutions 2260 Argentia Rd. Mississauga, Ontario L5N 6H7

Phone: 905-821-2600 Fax: 905-821-2055 Website: excelitas.com/omnicure

Phone: 703-478-0700 Email: uv@eit.com Website: eit.com

Curing Lamps American Ultraviolet A.W.T. World Trade, Inc. Clearstone Technologies Inc. Comet North America Dymax Oligomers & Coatings Excelitas Technologies GEW Inc. H&S Autoshot Inc. Hanovia Specialty Lighting LLC Henkel Corporation Heraeus Noblelight America LLC Honle UV America IST America

Primarc UV Curing Lamps, a Baldwin Technology brand 2 Danforth Drive Easton, PA 18045

Phone: 610-829-4240 Fax: 610-829-4260 Website: primarc.com

UV III Systems, Inc. 59 Cedarvale Estates Alburgh, VT 05440

Phone: 508-883-4881 Toll Free: 866-388-7880 Website: uv3.com

A.W.T. World Trade, Inc. 4321 N. Knox Avenue Chicago, IL 60641

Phone: 773-777-7100 Fax: 773-777-0909 Website: awt-gpi.com

13824 Magnolia Avenue Chino, CA 91710

Phone: 909-591-0276 Fax: 909-902-1638 Website: newportlab.com/uv-coldmirrors

EIT Instrument Markets 108 Carpenter Drive Sterling, VA 20164

Newport Thin Film Laboratory, Inc.

Miltec UV Nordson Corporation Prime UV-IR Systems, Inc. Primarc UV Curing Lamps, a Baldwin Technology brand Ushio America, Inc. UV III Systems, Inc.

Electron Beam Comet North America Energy Sciences Inc. PCT Engineered Systems

Ushio America, Inc. 5440 Cerritos Avenue Cypress, CA 90630

Phone: 800-838-7446 Fax: 800-776-3641 Website: ushio.com

Innovations in Optics, Inc. Integration Technology IST America Phoseon Technology Prime UV-IR Systems, Inc. Sunlite Science & Technology, Inc. Ushio America, Inc. XDS Holdings, Inc.

Overspray Collection Herding Filtration LLC

Dry Capture of Wet Coatings

Herding Filtration LLC 5479 Perry Drive, Suite D Waterford, MI 48329 Phone: 248-673-4514 Fax: 248-673-4926 Website: herding.us

Porex Corporation 500 Bohannon Road Fairburn, GA 30213

Phone: 800-241-0195 x1739 Email: electronics@porex.com Website: porex.com

Surface Preparation Bradley Systems Inc. Carestream Contract Manufacturing Nordson Corporation Sustainable Coatings

Ultraviolet American Ultraviolet A.W.T World Trade Inc. Baldwin Technology Carestream Contract Manufacturing Clearstone Technologies Inc. Dymax Oligomers & Coatings Electronic Materials Inc. Excelitas Technologies Flint Group GEW Inc. Gigahertz-Optik H&S Autoshot Inc. Hanovia Specialty Lighting LLC

LED

Heraeus Noblelight America LLC 910 Clopper Road Gaithersburg, MD 20878

Phone: 301-527-2660 Fax: 301-527-2661 Website: heraeus-noblelight.com

American Ultraviolet A.W.T. World Trade, Inc. Baldwin Technology Clearstone Technologies Inc. Dymax Oligomers & Coatings Excelitas Technologies GEW Inc. Heraeus Noblelight America LLC High Power Opto.Inc. Honle UV America

36 | UV+EB Technology • Issue 3, 2016

UV Curing and LED Curing Systems 212 South Mount Zion Rd. Lebanon, IN 46052

Phone: 765-483-9514 Toll Free: 800-288-9288 Website: americanultraviolet.com

uvebtechnology.com + radtech.org


PRODUCTS/SERVICES FORMULATED PRODUCTS 3D Printing/Photopolymers

UV-LED and Arc Solutions Baldwin Technology 14600 West 106th Street Lenexa, Kansas 66215 USA

Toll Free: 800-654-4999 Phone: 913-888-9800 Website: baldwintech.com

Nedap N.V.

Parallelweg 2 7141 DC Groenlo The Netherlands Phone: +31 544 471860 Website: www.nedap-uv.com

UV III Systems, Inc. 59 Cedarvale Estates Alburgh, VT 05440

Phone: 508-883-4881 Toll Free: 866-388-7880 Website: uv3.com

Henkel Corporation Heraeus Noblelight America LLC Herding Filtration LLC Honle UV America Integration Technology IRTronix Inc. IST America JB Machinery Inc. Keyland Polymer Miltec UV Nedap N.V. Netzsch Instruments North America LLC Nordson Corporation Primarc UV Curing Lamps, a Baldwin Technology brand Prime UV-IR Systems, Inc. RND Arastima Gelistirme Ltd Sti Strong-Coat, LLC Ushio America, Inc. UV III Systems, Inc. XDS Holdings, Inc.

Changzhou Tronly New Electronic Materials Colorado Photopolymer Solutions (CPS) Dymax Oligomers & Coatings Spectra Group Limited, Inc.

Adhesives & Sealants ACTEGA North America, Inc. Applied Molecules LLC Ashland Performance Materials BASF Corporation, Dispersions & Resins Beacon Adhesives Inc. Changzhou Tronly New Electronic Materials Colorado Photopolymer Solutions (CPS) Covestro, formerly Bayer MaterialScience LLC Cyngient Dymax Oligomers & Coatings Dyna-Tech Adhesives Electronic Materials Inc. Energy Sciences Inc. FSP Research, Inc. Hampford Research Inc. Henkel Corporation IGM Resins USA Inc. Inortech Chimie Inc. ITW Evercoat Joules Angstrom UV Printing Inks Corp. Lamberti SpA Lubrizol Advanced Materials Metamorphic Materials, Inc. Miltec UV MinusNine Technologies Novagard Solutions Rapid Cure Technologies, Inc. Royal Adhesives and Sealants LLC Shamrock Technologies Inc. Spectra Group Limited Inc. Strathmore Products, Inc. Sun Chemical Corporation Toyo Ink America, LLC Ushio America, Inc. Watson Standard Company

Coatings ACTEGA North America, Inc. Akzo Nobel Coatings, Inc. Allied PhotoChemical, Inc. American Inks and Coatings Applied Molecules LLC BASF Corporation, Dispersions & Resins Beacon Adhesives Inc. Beckers Industrial Coatings Ltd Carestream Contract Manufacturing Changzhou Tronly New Electronic Materials Chitec Technology Corp. Coatings & Adhesives Corporation Colorado Photopolymer Solutions (CPS) Covestro, formerly Bayer MaterialScience LLC Cyngient DSM

uvebtechnology.com + radtech.org

DVUV LLC Dymax Oligomers & Coatings Dyna-Tech Adhesives Electronic Materials Inc. Energy Sciences Inc. Estron Chemical, Inc. Eternal Materials Company LTD Flint Group FSP Research, Inc. Functional Materials Inc. Hampford Research Inc. Henkel Corporation IGM Resins USA Inc. Inortech Chimie Inc. INX International Ink Co. ITW Evercoat Joules Angstrom UV Printing Inks Corp. Keyland Polymer Keystone Research & Pharmaceutical Kolorcure Corporation Lamberti SpA Light Curable Coatings Lubrizol Advanced Materials Metamorphic Materials, Inc. Miltec UV MinusNine Technologies Nissan Chemical America Corporation Nova Pressroom Products Novagard Solutions Penn Color, Inc. PPG Coatings Innovation Center Prime Coatings Prime UV-IR Systems, Inc. Quaker Chemical Corporation R&D Coatings, Inc. Rapid Cure Technologies, Inc. Red Spot Paint & Varnish Co., Inc. Royal Adhesives and Sealants LLC Shamrock Technologies Inc. The Sherwin-Williams Co. Siegwerk USA Spectra Group Limited Inc. Strathmore Products, Inc. Strong-Coat, LLC Sun Chemical Corporation Sustainable Coatings Ushio America, Inc. UV Specialties, LLC UVCHEM Special Coatings Co., Ltd. Watson Standard Company Wikoff Color Corporation Zeller+Gmelin Corporation

Flint Group Functional Materials Inc. Ink Systems Inc Inortech Chimie Inc. INX International Ink Co. Joules Angstrom UV Printing Inks Corp. Kolorcure Corporation Penn Color, Inc. Rapid Cure Technologies, Inc. Siegwerk USA Strathmore Products, Inc. Sun Chemical Corporation Toyo Ink America, LLC Ushio America, Inc. Watson Standard Company Wikoff Color Corporation Zeller+Gmelin Corporation

RAW MATERIALS Additives Aal Chem Allnex Ashland Performance Materials BASF Corporation, Dispersions & Resins ChemHost Chitec Technology Corp. Double Bond Chemical Industries USA, Inc. Dymax Oligomers & Coatings Estron Chemical, Inc. Flint Group IGM Resins USA Inc. Kromachem, Inc. Lamberti SpA Lambson Ltd. (US) Lintech International Lubrizol Advanced Materials Miwon North America Nagase America Penn Color, Inc. rad-solutions llc RAHN USA Corporation Sartomer Americas Shamrock Technologies Inc. Siltech Corporation Spectra Group Limited Inc. Xamchem, LLC

Custom Colorado Photopolymer Solutions (CPS) IGM Resins USA Inc.

Siltech

Inks

225 Wicksteed Ave. Toronto, ON Canada M4H 1G5

ACTEGA North America, Inc. Allied PhotoChemical, Inc. American Inks and Coatings Applied Molecules LLC BASF Corporation, Dispersions & Resins Collins Inkjet Colorado Photopolymer Solutions (CPS) Cyngient DSM Energy Sciences Inc. Estron Chemical, Inc. Eternal Materials Company LTD

Phone: 416-424-4567 Fax: 416-424-3158 Website: siltech.com

Custom IGM Resins USA Inc.

Emulsions/Dispersions Alberdingk Boley, Inc.

UV+EB Technology â&#x20AC;¢ Issue 3, 2016 | 37


PRODUCTS/SERVICES Glass Optics

Oligomers

Kopp Glass

Aal Chem Allnex BASF Corporation, Dispersions & Resins Campbell & Co. Changzhou Tronly New Electronic Materials Covestro, formerly Bayer MaterialScience LLC Double Bond Chemical Industries USA, Inc. DSM-AGI Corporation Dymax Oligomers & Coatings Eternal Materials Company LTD IGM Resins USA Inc. Lintech International Melrob US Inc. Miwon North America Nagase America rad-solutions llc RAHN USA Corporation Sartomer Americas Siltech Corporation Xamchem, LLC

Kopp Glass

2108 Palmer Street Pittsburgh, PA 15218 Phone: 412-271-0190 Fax: 412-271-4103 Website: koppglass.com

Hybrid Polymers Alberdingk Boley Inc. Allnex

Light Stabilizers BASF Corporation, Dispersions & Resins

Aal Chem Allnex BASF Corporation, Dispersions & Resins Changzhou Tronly New Electronic Materials ChemHost Double Bond Chemical Industries USA, Inc. DSM-AGI Corporation Eternal Materials Company LTD Hampford Research Inc. IGM Resins USA Inc. Keystone Research & Pharmaceutical Kowa American Corporation Lambson Ltd. (US) Lintech International Melrob US Inc. Miwon North America Nagase America Penn Color, Inc. rad-solutions llc RAHN USA Corporation Sartomer Americas Synasia, Inc. Xamchem, LLC

Aal Chem Allnex Collins Inkjet Covestro, formerly Bayer MaterialScience LLC Flint Group Functional Materials Inc. INX International Ink Co. Kromachem, Inc. Lamberti SpA Lintech International Lubrizol Advanced Materials Nagase America Penn Color, Inc. Shamrock Technologies Inc. Spectra Group Limited Inc. Toyo Ink America, LLC Xamchem, LLC

Siltech Corporation

Dymax Oligomers & Coatings 318 Industrial Lane Torrington, CT 06790

Phone: 860-626-7006 Fax: 860-626-7043 Website: dymax-oc.com

RAHN USA Corporation 1005 N. Commons Drive Aurora, IL 60504

Phone: 630-851-4220 Fax: 630-851-4863 Website: rahn-group.com

Beacon Adhesives Inc. Carestream Contract Manufacturing Energy Sciences Inc. PCT Engineered Systems UV III Systems, Inc. Xamchem, LLC

Pigments/Dispersions

Reactive Silicones

Monomers

Pilot Lines

Lintech International Miwon North America Nagase America RAHN USA Corporation Spectra Group Limited Inc. Synasia, Inc.

SERVICES Consulting American Ultraviolet Applied Molecules LLC Beacon Adhesives Inc. Colorado Photopolymer Solutions (CPS) Dymax Oligomers & Coatings Excelitas Technologies KJCJ Consulting Paul Mills Consulting PCT Engineered Systems Pincus Associates, Inc. Prime UV-IR Systems, Inc. rad-solutions llc Rapid Cure Technologies, Inc. Primarc UV Curing Lamps, a Baldwin Technology brand Spectra Group Limited Inc. Strickland Photonics UV III Systems, Inc. UV Specialties, LLC Xamchem, LLC

UV III Systems, Inc. 59 Cedarvale Estates Alburgh, VT 05440

Phone: 508-883-4881 Toll Free: 866-388-7880 Website: uv3.com

Toll Services Carestream Contract Manufacturing Colorado Photopolymer Solutions (CPS) Dymax Oligomers & Coatings Dyna-Tech Adhesives Energy Sciences Inc. Estron Chemical, Inc. IGM Resins USA Inc. rad-solutions llc Rapid Cure Technologies, Inc. Synasia Inc. UV III Systems, Inc. UV Specialties, LLC Xamchem, LLC

Photoinitiators/Sensitizers

Nagase America 546 Fifth Avenue 16F New York, NY 10036

Phone: 212-703-1373 Website: nagaseamerica.com

Aal Chem Allnex BASF Corporation, Dispersions & Resins Campbell & Co. Changzhou Tronly New Electronic Materials Chitec Technology Corp. Colorado Photopolymer Solutions (CPS) Double Bond Chemical Industries USA, Inc. Hampford Research Inc. IGM Resins USA Inc. Kowa American Corporation Lambson Ltd. (US)

38 | UV+EB Technology â&#x20AC;˘ Issue 3, 2016

uvebtechnology.com + radtech.org


MANUFACTURERS DIRECTORY American Inks and Coatings PO Box 476 Sheridan, AR 72150 870-942-2662 americaninks.com

Aal Chem

2240 29th Street SE Grand Rapids, MI 49508 616-247-9851 aalchem.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Electronics; Biomedical/Medical; Glass; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

ACTEGA North America, Inc.

950 S. Chester Avenue, Suite B2 Delran, NJ 08075 800-255-0021 actega.com

Air Motion Systems Inc. 674 Highland Drive River Falls, WI 54022 715-425-5600

Akzo Nobel Coatings Inc. 1567 Prospect Street High Point, NC 27260 336-841-5111 akzonobel.com

6008 West Gate City Boulevard Greensboro, NC 27407 336-454-5000 alberdingkusa.com Industries Served: Concrete; Plastics & Composites; Printing & Packaging; Wood Finishing

Allied PhotoChemical, Inc. 48 N. Airport Road Kimball, MI 48074 810-364-6910 alliedphotochemical.com

Allnex

9005 Westside Parkway Alpharetta, GA 30009 770-280-8300 allnex.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Collision Repair/Refinishing; Electronics; Glass; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

uvebtechnology.com + radtech.org

14600 West 106th Street Lenexa, KS 66215 913-888-9800 baldwintech.com Industries Served: Plastics & Composites; Printing & Packaging

American Ultraviolet

212 S. Mount Zion Road Lebanon, IN 46052 800-288-9288 americanultraviolet.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Electronics; Biomedical/Medical; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing; Collision Repair & Refinishing

Applied Molecules, LLC

11042 Hi Tech Drive Whitmore Lake, MI 48189 810-355-1475 appliedmolecules.com Industries Served: 3D Printing; Automotive/ Transportation; Electronics; Glass; Plastics & Composites; Printing & Packaging

Ashland Performance Materials

Alberdingk Boley, Inc.

Baldwin Technology

5200 Blazer Parkway Dublin, OH 43017 614-790-3394 ashland.com

BASF Corporation, Dispersions & Resins

24710 W. Eleven Mile Road Southfield, MI 48034 800-231-7868 basf.us/dpsolutions Industries Served: Aerospace/Defense; Automotive/Transportation; Collision Repair & Refinishing; Electronics; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

Beacon Adhesives Inc.

125 S. MacQuesten Parkway Mt. Vernon, NY 10550 914-699-3400 beaconadhesives.com Industries Served: Aerospace/Defense; Automotive/Transportation; Electronics; Biomedical/Medical; Plastics & Composites; Printing & Packaging

Beckers Industrial Coatings Ltd.

A.W.T. World Trade, Inc.

4321 N. Knox Avenue Chicago, IL 60641 773-777-7100 awt-gpi.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Electronics; Glass; Metal Finishing; Plastics & Composites; Printing & Packaging

Goodlass Road, Speke GB-Liverpool L24 9HJ England +44-151-448-10-10 beckers-group.com

Bradley Systems Inc. 2720 S. River Road Des Plaines, IL 60018 800-252-1114 bradley-systems.com

Caldwell Chemical Coatings PO Box 898 Fayetteville, TN 37334 931-993-8448

Campbell & Co.

198 Main Street Charlemont, MA 01339 413-339-8333 campbell-uv.com

UV+EB Technology â&#x20AC;˘ Issue 3, 2016 | 39


MANUFACTURERS DIRECTORY Carestream Contract Manufacturing

8124 Pacific Avenue White City, OR 97503 800-234-8069 tollcoating.com Industries Served: Aerospace/Defense; Automotive/Transportation; Electronics; Biomedical/Medical; Printing & Packaging; Glass

Changzhou Tronly New Electronic Materials

Quianjiang, Changzhou China 240-515-8280 Industries Served: 3D Printing; Automotive/ Transportation; Glass; Metal Finishing; Printring/Packaging

ChemHost

Comet North America

100 Trap Falls Road Extension Shelton, CT 06484 203-447-3165 comet-ebeam.com

100 Bayer Road Pittsburgh, PA 15205 800-662-2927 covestro.com

318 Industrial Lane Torrington, CT 06790 860-626-7006 dymax-oc.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Electronics; Glass; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

Cyngient

Dyna-Tech Adhesives

Covestro, formerly Bayer MaterialScience LLC

41 Plymouth Street Fairfield, NJ 07004 973-882-4600 cyngient.com Industries Served: Printing & Packaging

777 Schwab Road, Suite W Hatfield, PA 19440 215-855-5378 chemhost.com

Digital Light Lab

Chitec Technology Corp.

Double Bond Chemical Industries USA, Inc.

20F, No. 57, Sec. 2, Dunhua S Road Taipei City, 106 Taiwan +886 2-2700-6678 chitec.com/english/

Clearstone Technologies Inc.

625 St. Louis Street, Suite 35 Hopkins, MN 55343 612-824-4846 clearstonetech.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Collision Repair/Refinishing; Electronics; Biomedical/Medical; Metal Finishing; Printing & Packaging; Wood Finishing

185 Farms Village Road T West Simsbury, CT 06092 860-408-1216 double-bond-chem.com.tw

DSM

1122 St. Charles Street Elgin, IL 60120 800-222-7189 dsm.com

DSM-AGI Corporation

1901 Popular Street NE Leland, NC 28451 910-371-3184 cacoatings.com

Collins Inkjet

DVUV LLC

1201 Edison Drive Cincinnati, OH 45216 513-948-9000 collinsinkjet.com

Colorado Photopolymer Solutions (CPS) 1880 S. Flatiron Court Boulder, CO 80301 303-551-3213 cpspolymers.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Biomedical/Medical; Collision Repair/ Refinishing; Electronics; Glass; Metal Finishing; Plastics/Composites; Printing/ Packaging; Wood Finishing

40 | UV+EB Technology â&#x20AC;˘ Issue 3, 2016

2071 Country Club Road Grafton, WV 26354 304-265-5200 dyna-techadhesives.com Industries Served: Printing & Packaging

10820 Murdock Drive Knoxville, TN 37932 865-694-7862

730 Main Street Wilmington, MA 01887 978-821-6340 dsm-agi.com Industries Served: 3D Printing; Automotive/ Transportation; Collision Repair/Refinishing; Electronics; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

Coatings & Adhesives Corporation

Dymax Oligomers & Coatings

4641 Hinckley Industrial Parkway Cleveland, OH 44109 216-741-5511 dvuv.com

EIT Instrument Markets

108 Carpenter Drive Sterling, VA 20164 703-478-0700 eit.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Electronics; Biomedical/Medical; Printing & Packaging; Wood Finishing; Glass; Metal Finishing; Plastics & Composites

Electronic Materials Inc. 1814 Airport Road Breckenridge, CO 80424 970-547-0807 emiuv.com

Enercon Industries Corporation W140 N9572 Fountain Boulevard Menomonee Falls, WI 53051 262-255-6070

Energy Sciences Inc. 42 Industrial Way Wilmington, MA 01887 978-694-9000 ebeam.com

Estron Chemical, Inc.

807 N. Main Street, PO Box 127 Calvert City, KY 42029 800-662-3642 estron.com

uvebtechnology.com + radtech.org


MANUFACTURERS DIRECTORY Eternal Materials Company LTD 578 Chien-Kung Road Kaohsiung 807 Taiwan, China +886-7696-3331 x 500 eternal-group.com

H&S Autoshot Inc.

49 Mountainview Road North Georgetown, Ontario L7G4J7 Canada 905-873-1813 hsautoshot.com

High Power Opto, Inc.

No. 8, Keyuan 3rd Road, Xitun District Taichung City 407 Taiwan +886-4-2465-7899 hpoled.com.tw/en/

Hampford Research Inc.

Excelitas Technologies

2260 Argentia Road Mississauga, Ontario, Canada L5N 6H7 905-821-2600 excelitas.com/omnicure Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Collision Repair/Refinishing; Glass; Electronics; Biomedical/Medical; Printing & Packaging; Plastics & Composites; Wood Finishing

Flint Group

1130 James L. Hart Parkway Ypsilanti, MI 48197 734-879-5000 flintgrp.com

FSP Research, Inc. PO Box 28 Milford, CT 06460 203-874-3417 fspresearch.com

Functional Materials Inc. 100 Wells Avenue Congers, NY 10920 845-753-6000 functionalmaterials.com

54 Veterans Boulevard Stratford, CT 06615 203-375-1137 hampfordresearch.com

Hanovia Specialty Lighting LLC 6 Evans Street Fairfield, NJ 07004 973-651-5510 hanovia-uv.com

Haward International

7 Tanjong Rhu Road #1601 Singapore 436887 Singapore +6563453561

Henkel Corporation 203 MacKenan Court Cary, NC 27511 919-319-1933 henkelna.com

Heraeus Noblelight America LLC 910 Clopper Road Gaithersburg, MD 20878 301-527-2660 heraeus-noblelight.com/fusionuv Industries Served: Aerospace/Defense; Automotive/Transportation; Electronics; Glass; Biomedical/Medical; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

Honle UV America

261 Cedar Hill Street, Building C Marlboro, MA 01752 508-229-7774 honleuv.com Industries Served: Automotive/ Transportation; Collision Repair/Refinishing; Electronics; Glass; Biomedical/Medical; Plastics & Composites; Printing & Packaging

Horn Ventures International 12 Stanley Court, Unit 4B Whitby, ON L1N 8P9 Canada

IGM Resins USA Inc.

3300 Westinghouse Boulevard Charlotte, NC 28273 704-945-8775 igmresins.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Collision Repair/Refinishing; Electronics; Glass; Biomedical/Medical; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

Ink Systems Inc.

GEW Inc.

11941 Abbey Road, Unit X North Royalton, OH 44133 440-237-4439 gewuv.com Industries Served: Metal Finishing; Printing & Packaging; Wood Finishing

Gigahertz-Optik

5 Perry Way Newburyport, MA 01950 978-462-1818 gigahertz-optik.com

uvebtechnology.com + radtech.org

Herding Filtration, LLC

5479 Perry Drive, Suite D Waterford, MI 48329 248-673-4514 herding.us Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Biomedical/Medical; Glass; Metal Finishing; Plastics/Composites; Printing/Packaging; Wood Finishing; Ceramics

2311 S. Eastern Avenue Commerce, CA 90040 323-720-4000 inksystemsinc.com

Innovations in Optics, Inc.

82 Cummings Park Woburn, MA 01801 781-933-4477 innovationsinoptics.com Industries Served: 3D Printing; Electronics; Plastics & Composites; Printing & Packaging; Wood Finishing

UV+EB Technology â&#x20AC;˘ Issue 3, 2016 | 41


MANUFACTURERS DIRECTORY Inortech Chimie Inc.

3014 Rue Anderson Terrebonne, Quebec J6Y1W1 450-621-1999 inortech.com

Integration Technology

590 Territorial Drive, Suite A Bolingbrook, IL 60440 630-410-2189 uvintegration.com

INX International Ink Co.

150 North Martingale Road, Suite 700 Schaumburg, IL 60173 630-382-1800 inxinternational.com

Keystone Research & Pharmaceutical 480 South Democrat Road Gibbstown, NJ 08027 856-663-4700

KJCJ Consulting

37232 Wild Rose Lane Murrieta, CA 92562 951-445-3151 mwvkdv.wix.com/kjcj-consulting

Kolorcure Corporation 1180 Lyon Road Batavia, IL 60510 630-879-9050 kolorcure.com

IRTronix Inc.

635 Hawaii Avenue Torrance, CA 90710 310-787-1100 itronix.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Electronics; Biomedical/Medical; Plastics & Composites; Printing & Packaging; Wood Finishing

Kopp Glass

IST America

590 Territorial Drive, Suite A Bolingbrook, IL 60440 630-771-0590 ist-uv.com

2108 Palmer Street Pittsburgh, PA 15218 412-271-0190 koppglass.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Collision Repair/Refinishing; Electronics; Glass; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

ITW Evercoat

Kowa American Corporation

LED Specialists, Inc.

4250 Veterans Memorial Highway Suite 2060 West Holbrook, NY 11741 631-269-4235

Light Curable Coatings 140 Sheldon Road Berea, OH 44017 216-642-0626 lccoat.com

Lintech International

7705 NE Industrial Boulevard Macon, GA 31216 877-546-8324 lintechinternational.com Industries Served: Aerospace/Defense; Collision Repair/Refinishing; Electronics; Glass; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

Lubrizol Advanced Materials 9911 Brecksville Road Cleveland, OH 44141 216-447-5000 lubrizol.com

Melrob US Inc.

6600 Cornell Road Cincinnati, OH 45242 513-489-7600 evercoat.com

55 E. 59th Street, 19th Floor New York, NY 10020 262-554-6729 chemical.kowa.com

JB Machinery Inc.

Kromachem Inc.

9 Sasqua Trail Weston, CT 06883 203-544-0101 jbmachinery.com

30 Southard Avenue Farmingdale, NJ 07727 732-751-0980 kromachem.com

6900 Philips Highway, Suite 32 Jacksonville, FL 32216 904-997-1800 melrob.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive; Electronics; Glass; Medical Devices; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

Joules Angstrom UV Printing Inks Corp.

Lamberti SpA

Metamorphic Materials, Inc.

104 Heritage Drive Pataaskala, OH 43062 740-964-9113 joulesangstrom.com Industries Served: Automotive/ Transportation; Plastics & Composites; Printing & Packaging

Keyland Polymer

4621 Hinckley Industrial Parkway Cleveland, OH 44109 216-741-7915 keylandpolymer.com Industries Served: Aerospace/Defense; Automotive/Transportation; Electronics; Biomedical/Medical; Metal Finishing; Plastics & Composites; Wood Finishing

42 | UV+EB Technology â&#x20AC;˘ Issue 3, 2016

Via Marsala 38/D 21013 Gallarate Italy +39-331-715111 lamberti.com

Lambson Ltd. (US)

301 Route 17 North, 8th Floor Rutherford, NJ 07070 201-842-7640 lambson.com Industries Served: 3D Printing; Aerospace/ Defense; Electronics; Biomedical/Medical; Plastics & Composites; Printing & Packaging; Wood Finishing; Metal Finishing

122 Colebrook River Road Winsted, CT 6098 860-738-8638

Miltec UV

146 Log Canoe Circle Stevensville, MD 21666 410-604-2900 miltec.com

MinusNine Technologies 200H North Furnace Street Birdsboro, PA 19508 888-672-2123 minus9.com

uvebtechnology.com + radtech.org


MANUFACTURERS DIRECTORY PCT Engineered Systems

Miwon North America 696 W. Lincoln Highway Exton, PA 19341 484-872-8711 miwonus.com

Nagase America

546 Fifth Avenue, Suite 16F New York, NY 10036 212-703-1373 nagaseamerica.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Biomedical/Medical; Collision Repair/ Refinishing; Electronics; Glass; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

NAZDAR Ink Technologies 8501 Hedge Lane Terrace Shawnee, KS 66227 913-422-1888

Nedap N.V.

Newport Thin Film Laboratory, Inc.

13824 Magnolia Avenue Chino, CA 91710 909-591-0276 http://newportlab.com/uv-cold-mirrors Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Biomedical/Medical; Collision Repair/ Refinishing; Electronics; Glass; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

Penn Color, Inc.

Nissan Chemical America Corporation

Phoseon Technology

10375 Richmond Avenue, Suite 1000 Houston, TX 77042 713-532-4745 nissanchem-usa.com

Nordson Corporation 28601 Clemens Road Westlake, OH 44145 440-892-1580 nordson.com

Nova Pressroom Products

1663 N. McDuff Avenue Jacksonville, FL 32254 904-292-2554 novapressroom.com Industries Served: Printing & Packaging

Parallelweg 2 7141 DC Groenlo The Netherlands +1-0031-544-471-111 nedap-uv.com Industries Served: Electronics; 3D Printing; Aerospace/Defense; Automotive/ Transportation; Biomedical/Medical; Collision Repair/Refinishing; Glass; Metal Finishing; Printing & Packaging; Wood Finishing

Novagard Solutions

Netzsch Instruments North America LLC

Opsytec Dr. Grรถbel GmbH

129 Middlesex Turnpike Burlington, MA 01803 781-272-5353 netzsch-thermal-analysis.com

8700 Hillandale Road Davenport, IA 52806 563-285-7411 teampct.com Industries Served: Metal Finishing; Printing & Packaging

5109 Hamilton Avenue Cleveland, OH 44114 216-881-8111 novagard.com

400 Old Dublin Pike Doylestown, PA 18901 866-617-7366 penncolor.com

7425 NW Evergreen Parkway Hillsboro, OR 97124 503-439-6446 phoseon.com

Pincus Associates, Inc.

9 Willard Circle Andover, MA 01810 978-475-9197 pincusassociates.webs.com

PL Industries

48 Powhattan Avenue Essington, PA 19029 800-245-3800

Poly6 Technologies

21 Drydock Ave, 610E Boston, MA 02210 617-575-9291

Novus Inc.

650 Pelham Boulevard, Suite 100 St Paul, MN 55378 952-944-8000 Goethestr. 17 Ettlingen 76275 Germany +4972439478350

Paul Mills Consulting 1477 Troon Avenue Brunswick, OH 44212 440-570-5228

Porex Corporation

500 Bohannon Road Fairburn, GA 30213 800-241-0195 porex.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Electronics; Glass; Biomedical/Medical; Plastics & Composites; Printing & Packaging; Wood Finishing

PPG Coatings Innovation Center 4325 Rosanna Drive Allison Park, PA 15101 412-492-5200 ppgac.com

uvebtechnology.com + radtech.org

UV+EB Technology โ€ข Issue 3, 2016 | 43


MANUFACTURERS DIRECTORY

Primarc UV Curing Lamps, a Baldwin Technology brand

2 Danforth Drive Easton, PA 18045 610-829-4240 primarc.com Industries Served: 3D Printing; Automotive/ Transportation; Electronics; Glass; Biomedical/Medical; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

Prime Coatings

1002 Hickory Street Pewaukee, WI 53072 262-691-1930 primecoatings.net

Prime UV-IR Systems, Inc.

416 Mission Street Carol Stream, IL 60188 630-681-2100 primeuv.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Electronics; Glass; Biomedical/Medical; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

Prochema Handels GmBH Wienerbergstrasse 3 Vienna, Austria 1100 Austria +0043 1605 60 12

Quaker Chemical Corporation

RAHN USA Corporation

Sartomer Americas

Rapid Cure Technologies, Inc.

Shamrock Technologies Inc.

1005 N. Commons Drive Aurora, IL 60504 630-851-4220 rahn-group.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Collision Repair/Refinishing; Electronics; Glass; Biomedical/Medical; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing 7030 Fly Road East Syracuse, NY 13057 888-847-3610 rapidcuretechnologies.com Industries Served: Aerospace/Defense; Automotive; Electronics; Glass; Metal Finishing; Plastics & Composites; Printing & Packaging

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44 | UV+EB Technology â&#x20AC;˘ Issue 3, 2016

299 Pacific Street Newark, NJ 07114 973-242-2999 shamrocktechnologies.com

Sherwin-Williams Co., The 113 Stagecoach Trail Greensboro, NC 27409 336-292-3000 sherwin-williams.com

Siegwerk USA

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RND Arastima Gelistirme Ltd Sti

One Quaker Park, 901 E. Hector Street Conshohocken, PA 19428 610-832-4000 quakerchem.com 1320 Island Avenue, PO Box 418 McKees Rocks, PA 15136 877-378-9860 rdcoatings.com

502 Thomas Jones Way Exton, PA 19341 610-363-4100 sartomer.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Collision Repair/Refinishing; Electronics; Glass; Biomedical/Medical; Metal Finishing; Plastics & Composites; Printing & Packaging; Wood Finishing

89 Cumberland Street PO Box 5000 Westbrook, ME 04092 207-856-3542

Siltech Corporation

225 Wicksteed Avenue Toronto, Ontario, Canada M4H 1G5 416-424-4567 siltech.com Industries Served: 3D Printing; Automotive; Plastics & Composites; Printing & Packaging; Wood Finishing

Spectra Group Limited Inc.

27800 Lemoyne Road, Suite J Millbury, OH 43447 419-837-9783 sglinc.com Industries Served: 3D Printing; Plastics & Composites Strathmore Products, Inc. 1970 W. Fayette Street Syracuse, NY 13204 315-488-5401 strathmoreproducts.com

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MANUFACTURERS DIRECTORY Strickland Photonics

PO Box 5798 Oceanside, CA 92052 760-450-4095 strickland-photonics.com Industries Served: Biomedical/Medical

Strong-Coat, LLC

4420 Sherwin Road Willoughby, OH 44094 440-299-2068 strong-coat.com

Sun Chemical Corporation

Xamchem, LLC

Ushio America, Inc.

5440 Cerritos Avenue Cypress, CA 90630 800-838-7446 ushio.com Industries Served: 3D Printing; Automotive/ Transportation; Biomedical/Medical; Plastics & Composites; Printing & Packaging; Wood Finishing

35 Waterview Boulevard Parsippany, NJ 07054 973-404-6000 sunchemical.com

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XDS Holdings, Inc. 2461 Progress Court Neenah, WI 54956 920-722-8123 teamxds.com

Zeller+Gmelin Corporation 4801 Audubon Drive Richmond, VA 23231 800-848-8465 zeller-gmelin.com

Sunlite Science & Technology, Inc. 4811 Quail Crest Place Lawrence, KS 66049 785-856-0219 sunlitest.com

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UV III Systems, Inc.

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Synasia, Inc.

240 Amboy Avenue Metuchen, NJ 08840 732-205-9880 synasia.com Industries Served: 3D Printing; Aerospace/ Defense; Automotive/Transportation; Electronics; Plastics & Composites; Printing & Packaging; Wood Finishing

Toyo Ink America, LLC 1225 N. Michael Drive Wood Dale, IL 60191 866-969-8696 toyoink.com

Toyoda Gosei

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UVCHEM Special Coatings Co., Ltd.

Xinzhai Industry Zone, Xiaoyue, Shangyu, Zhejiang, China +86-575-82038998 uvchem.com.cn

Watson Standard Company 616 Hite Road Harwick, PA 15049 724-275-1000 watsonstandard.com

Wikoff Color Corporation 1886 Merritt Road Fort Mill, SC 29715 803-548-2210 wikoff.com

UV+EB Technology â&#x20AC;˘ Issue 3, 2016 | 45


BEST PAPER By Andrea Bernini Freddi, Marika Morone and Gabriele Norcini, IGM Resins, Gerenzano (VA), Italy

Design of New 3-ketocoumarins for UV LED Curing Editors Note: The following received RadTech 2016’s Best Paper Award at the event held May 16-18 in Chicago, Illinois. Abstract ight emitting diodes (LED) are becoming a valid alternative to Hg lamps in most radiation-curable applications. Matching photoinitiator absorbance with the operation wavelength of the LED source is crucial.

L

In this paper, we will describe how is possible to modify the physical-chemical properties of 3-ketocoumarins and how such modifications influence reactivity. We will be able to design new 3-ketocoumarins with good solubility, high reactivity and low yellowing for clear and pigmented coatings. These new molecules were always compared to thioxanthones and acylphosphine oxides, which are the only two classes of photoinitiators that show good performance at 365 and 395 nm1 (most powerful operation wavelength for LED). Introduction Among the light radiation sources used in UV curing, light emitting diodes (LED) have been the subject of significant development over the past few years because of the advantages of low temperature operation, extremely long life, instant start and low energy consumption as compared to conventional medium pressure mercury lamps. Unfortunately, while these lamps provide a series of line outputs that cover all the UV spectrum, commercial LED lamp output is a single peak, centered at 365 nm or 395 nm (most powerful), with a very narrow bandwidth. Therefore, formulating for LED lamps requires photoinitiators that absorb most efficiently in the range of 365 nm and 395 nm, since these are the only outputs of most of LED lamps. Up to now the photoinitiators most commonly used in this field belong to the classes of thioxanthones (ITX) and acylphosphine oxides (TPO, BAPO). Unfortunately, thioxanthone derivatives, commonly used as sensitizers and photoinitiators, are prone to yellowing upon exposure, and this strongly limits the use of such derivatives in all the applications for which color stability is mandatory, e.g. graphic arts. Acyl phosphine oxide photoinitiators, on the other hand, when air cured, are very sensitive to oxygen inhibition and do not give surface cure, leaving a tacky surface. Therefore, demand is increasing for the development of different photoinitiators with absorbtion in the 360 to 400 nm region, good photochemical activity, and low oxygen sensitivity and yellowing. In this paper, we describe how to modify the photophysical properties of 3-ketocoumarins to create a new class of photoinitiators for LED lamps. Results and discussion Synthesis. The 3-ketocoumarin derivatives are easily prepared by the condensation of salicylaldehyde derivatives with β-ketoesters.2 46 | UV+EB Technology • Issue 3, 2016

R2

R3

O H

R1

OH 2

+ R O 4

R2 -R4OH

O

3

O

O

piperidine

R3 R1

O

O

1

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48 | UV+EB Technology • Issue

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BEST PAPER t page 46 TABLE 1. Molecular structures and ε values at 395 nm of the new 3-ketocoumarins R1

R2

R3

ε value (395nm)

LFC3220

OCH3

H

t-but

835

LFC2887

OCH3

H

H

925

LFC3224

OCH3

H

SR6

1470

LFC3260

OCH3

OCH3

t-but

3894

LFC3228

OCH3

OCH3

H

4332

LFC3221

H

naphthalene

t-but

5774

LFC3218

H

naphthalene

H

6484

LFC3195

Julolidine

H

H

8530

LFC3226

SR5

H

H

9411

LFC3191

NEt2

H

H

24641

Absorption Spectra. As shown in Figure 1, the ketocoumarins have absorption maxima ranging from 340 nm and 450 nm in acetonitrile, and the ε value at 395 nm is enhanced when an electron-donating group is on the phenyl ring or coumarin ring. The highest values are reached with the amine substitution on the coumarin nucleous (Table 1). UV LED Curing Tests. The first test for the evaluation of the new 3-ketocoumarin reactivity was performed by the measure of the double-bond conversion (1407 and 810 cm-1) by FT-IR in a clear coating. The photopolymerizable compositions for the test were prepared dissolving the photoinitiator and the co-initiator (Ethyl-4-dimethylamino benzoate, EDB) at a concentration of 3% by weight each in a mixture 99.5:0.5 wt of bisphenol A epoxy diacrylate and silicone diacrylate. The LED source used was an LX400+ system equipped with a UV LED spot centered at 400nm (Excelitas).

1.2

1

ITX

0.8

TPO Absorbance

The substituents R1, R2 and R3 in Table 1 can be widely varied. Several derivatives have been prepared as reported in Table 1.

LFC3191 LFC3195

0.6

LFC2887

Isopropyl Thioxanthone (ITX) and Diphenyl(2,4,6trimethylbenzoyl)phosphine oxide (TPO) were used as reference.

LFC3220 0.4

LFC3228 LFC3260 LFC3218

0.2

0

250

300

350

400 Wavelength [nm]

450

500

550

Figure 1. UV-Vis Spectra in Acetonitrile 0.001% w/w.

FIGURE 1. UV-Vis Spectra in Acetonitrile 0.001% w/w.

% Double Bond Conversion at 1407 cm-1

UV-LED Curing Tests The first test for the evaluation of the new 3-ketocoumarin reactivity was performed by the measure of 80 the double-bond conversion (1407 and 810 cm-1) by FT-IR in a clear coating. TPO and the 70 The photopolymerizable compositions for the test were prepared dissolving the photoinitiator co-initiator (Ethyl-4-dimethylamino benzoate, EDB) at a concentration of 3% by weight ITX each+ in a EDB 60 99.5:0.5 wt of bisphenol A epoxy diacrylate and silicone diacrylate. The LED source used was mixture LFC3191 + EDB an LX400+ system equipped with a UVLED spot centered at 400nm (Excelitas). LFC3195 + EDB

50

LFC2887 + EDB Isopropyl 40 Thioxanthone (ITX) and Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO) were used LFC3220 + EDB as reference. LFC3218 + EDB

30

LFC3221 + EDB

20

LFC3226 + EDB LFC3228 + EDB

10 0

LFC3260 + EDB 0

0.5

1

1.5

2 Time[s]

2.5

3

3.5

4

When measuring the activity of these molecules in a cyan ink for inkjet printing, the concentration of the photoinitiator and the co-initiator was 5% each by weight. The best performances are shown in Figure 3. The highest value of conversion is reached from the sulfur substituted ketocoumarin (LFC3226), while the lowest is reached from TPO. Figures 2 and 3 clearly show that ketocoumarins containing medium-strength electron-donating groups (such as O, S) are good candidates for working with LED at 395 nm. The same result is reached using an LED 365 nm lamp.

LFC3224 + EDB

Figure 2. FT-IR at 400nm in clear coating. Conditions: PE substrate, 6 µm thickness, under air.

FIGURE 2. FT-IR at 400nm in clear coating. Conditions: PE

Figure 2 shows the most reactive molecule under is LFC3260 (66% at 1’), followed by ITX and LFC3220 substrate, 6 mm thickness, air. (63% at 1’) and TPO (55% at 1’). The worst instead are the amine substituted ketocoumarins, which are both below 5% of conversion.

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Figure 2 shows the most reactive molecule is LFC3260 (66% at 1’), followed by ITX and LFC3220 (63% at 1’) and TPO (55% at 1’). The worst instead are the amine substituted ketocoumarins, which are both below 5% of conversion.

When measuring the activity of these molecules in a cyan ink for inkjet printing, the concentration of the photoinitiator and the co-initiator was 5% each by weight. The best performances are shown in Figure 3.

The 3-ketocoumarins LFC3220, LFC3260 and LFC3226 were further evaluated. Through-cure measures were performed at 395 nm (4W) and 365 nm (12 W) in a cyan page 50 u UV+EB Technology • Issue 3, 2016 | 49


Figure 2. FT-IR at 400nm in clear coating. Conditions: PE substrate, 6 µm thickness, under air.

Figure 2 shows the most reactive molecule is LFC3260 (66% at 1’), followed by ITX and LFC3220 (63% at 1’) and TPO (55% at 1’). The worst instead are the amine substituted ketocoumarins, which are both below 5% of conversion.

BEST PAPER

When measuring the activity of these molecules in a cyan ink for inkjet printing, the concentration of the photoinitiator and the co-initiator was 5% each by weight. The best performances are shown in Figure 3.

t page 49

inkjet ink (Figures 4 and 5). The solutions of photoinitiator and co-initiator were prepared at a concentration of 3 and 6% each by weight.

90

% DB conversion at 1407 cm-1

80 70

At 395 nm, LFC3226 and LFC3260 show reactivity much higher than ITX at both ITX+EDB 50 TPO air. Figure 3. FT-IR at 400nm in cyan inkjet ink. Conditions: PE substrate, 12 µm thickness, under concentrations, while LFC3220 shows a 40 LFC3260 +EDB reactivity similar to TPO (Figure 4). Despite LFC3220 +EDB 30 of conversion is reached from the sulfur substituted ketocoumarin e highest value (LFC3226), while the good reactivity, LFC3226, the alkylthio LFC3226+EDB lowest is reached from TPO. derivative, was rejected because of yellowing 20 (Figures 6 and 7). 10 ures 2 and 3 clearly show that ketocoumarins containing medium-strength electron-donating groups 0 good candidates for working with LED at 395 nm. The same result is reached using an ch as O, S) are At 365 nm, LFC3260 is the best performer 0 0.5 1 1.5 2 2.5 3 3.5 4 D 365 nm lamp. Time [s] (Figure 5). It shows a reactivity twice that of ITX. LFC3220 also shows good reactivity, but e 3-ketocoumarins LFC3226 wereConditions: further evaluated. Through-cure measures FIGURE 3.LFC3220, FT-IR at LFC3260 400nm inand cyan inkjet ink. PE substrate, is significantly lower than that of LFC3260. re performed at thickness, 395 nm (4W) and 365 12 mm under air. nm (12 W) in a cyan inkjet ink (Figures 4 and 5). The solutions photoinitiator and co-initiator were prepared at a concentration of 3 and 6% each by weight. Yellowing. The color stability of LFC3260 and

Relative Speed m/min

60

LFC3226 also was evaluated in clear ink for inkjet printing by a color guide BYK 45/0. The results are summarized in Figure 6.

81

90 80 70 60 50 40 30 20 10 0

65 50

Both ketocoumarins show a yellowing higher than that of TPO, but while LFC3226 is also more yellow than ITX, LFC3260 shows lower values in all measurements.

42

33 23 6 ITX +EDB

TPO

8

7 LFC3226 +EDB 3%

LFC3260 + EDB

12

LFC3220 +EDB

6%

An acrylated amine as co-initiator was also evaluated (Figure 7), and the b* value of LFC3260 was significantly reduced as compared to LFC3226 and ITX.

Sensitization. To complete the characterization Figure 4. Through-cure measurement at 395 nm in cyan inkjet ink. Conditions: cartonboard, 6 µm thickness. FIGURE 4. Through-cure measurement at 395 nm in cyan inkjet ink. of the new ketocoumarins the ability of Conditions: cartonboard, 6 mm thickness. 395 nm, LFC3226 and LFC3260 show reactivity much higher than ITX at both concentrations,LFC3260 while and LFC3220 as sensitizers for an aminoketone (2-Methyl-1-[4-(methylthio) C3220 shows a reactivity similar to TPO (Figure 4). Despite the good reactivity, LFC3226, the phenyl]-2-morpholinopropan-1-one, MPMP) ylthio derivative, was rejected because of yellowing (Figures 6 and 7). 90 was evaluated. 90

67

Relative Speed m/min

80 70 60

45

50 40 30 20 10 0

ITX +EDB

LFC3260 + EDB

LFC3220 + EDB

The test was performed by FT-IR in a clear formulation (bisphenol A epoxy diacrylate/ silicone diacrylate 99,5:0,5 by weight), with a concentration of PI at 4% and sensitizer at 0,5 by weight. An LX400+ system equipped with a UV LED spot centered at 400 nm (Excelitas) was used as light source (Figure 8). These data, even if in clear coating, seem to indicate a quite good activity of LFC3260 as sensitizer.

Figure 5.FIGURE Through-cure at 365 nm in cyan inkjet ink. Conditions: cartonboard, µm thickness; 5.measurement Through-cure measurement at 365 nm in cyan6inkjet ink. PI and co-initiator concentration: 6% w/w. In conclusion,

we were able to tune the Conditions: cartonboard, 6 mm thickness; PI and co-initiator concentration: absorption wavelength of the 3-ketocoumarins w/w. is the best performer (Figure 5). It shows a reactivity twice that of ITX. LFC3220 365 nm,6% LFC3260 to balance absorption, reactivity and yellowing. o shows good reactivity, but is significantly lower than that of LFC3260. The 3-ketocoumarin that showed best results is

llowing 50 | UV+EB Technology • Issue 3, 2016 e color stability of LFC3260 and LFC3226 also was evaluated in clear ink for inkjet printing by a or guide BYK 45/0. The results are summarized in Figure 6.

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so shows good reactivity, but is significantly lower than that of LFC3260.

ellowing he color stability of LFC3260 and LFC3226 also was evaluated in clear ink for inkjet printing by a lor guide BYK 45/0. The results are summarized in Figure 6. LFC3260, which is strongly reactive in all tests. In fact, it shows a reactivity twice that of ITX in through-cure measurements at 395 nm and 365 nm and significantly less yellowing.

12 10 b* value

8 6 4 2 0

TPO

ITX+EDB after curing

LFC3260 + EDB 3 days

LFC3226 + EDB

10 days

Figure 6. b* value over time. Conditions: 2 pass at 30 m/min, 16 W LED at 395 nm; cartonboard 6 µm thickness; FIGURE 6. b* value over time. Conditions: 2 pass at 30 m/min, 16 W LED concentration: PI and co-initiator 3% w/w.

Experimental Section Synthesis. The 3-ketocoumarins in Table 1 were synthesized as described in Scheme 1. The general procedure is as follows: To a solution of 2,75 mmol of aldehyde 2 and 2,75 mmol of β-ketoester 3 in 15 ml of ethanol were added 0,5 ml of piperidine. After three hours under reflux, the reaction mixture was cooled down, and the reaction product 1 crystallized at room temperature. The solid was recovered by filtration (yield of 70 to 90%).

b* value

b* value

at 395 nm; cartonboard 6 mm thickness; concentration: PI and co-initiator 3% w/w. show a yellowing higher than that of TPO, but while LFC3226 is also more yellow oth ketocoumarins Polymerization. FT-IR experiments. The an ITX, LFC3260 shows lower values in all measurements. photopolymerizable compositions for the tests 7 were prepared dissolving the photoinitiator and 6 n acrylated amine as co-initiator was also evaluated (Figure 7), and the b* value of LFC3260 was the co-initiator at 40° C. Films with uniform5 7 as compared gnificantly reduced to LFC3226 and ITX. layer thickness were prepared by applying the 4 6 3 formulation on a polyethylene foil with a K101 5 2 control coater (bar no. 1 for clear coating and 4 1 no. 2 for cyan inkjet ink). 3

0

TPO

ITX+ Acrylated Amine

LFC3260 + Acrylated Amine

LFC3226 + Acrylated Amine

The film was placed in the sample lodgment of an FT-IR (FT-IR 430-Jasco) and was 1 exposed to a 400 nm LED (powered by an Figure 7. b* value over time. Conditions: 2 pass at 30 m/min, 16W LED at 395 nm; cartonboard 6 µm thickness; 0 Concentration: PI and co-initiator 3% w/w+ TPO ITX+ Acrylated LFC3260 LFC3226 + external OmniCure LX400+ power source) Amine Acrylated Amine Acrylated Amine located at a distance of 65 mm from the Sensitization sample and at an angle of 30°. IR spectra were To complete the characterization of the new ketocoumarins ability after curing 3 days the10 days of LFC3260 and LFC3220 as sensitizers for an aminoketone (2-Methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, MPMP) acquired at constant time intervals during the was evaluated. Figure 7. b* value over time. Conditions: 2 pass at 30 m/min, 16W LED at 395 nm; cartonboard 6 µm thickness; photopolymerization, and the reduction over the FIGURE 7. b* value over time. Conditions: 2 pass at 30 m/min, 16W LED Concentration: PI and co-initiator 3% w/w time of the area of the peaks at 1408 and 810 at nm;performed cartonboard thickness; PI and co-initiator The395 test was by FT-IR6inmm a clear formulation Concentration: (bisphenol A epoxy diacrylate/silicone diacrylate 99,5:0,5 by weight), with a concentration of PI at 4% and sensitizer at 0,5 by weight. An cm-1 assigned to the acrylic double-bond was 3% w/w ensitization LX400+ system equipped with a UV LED spot centered at 400nm (Excelitas) was used as light source. using the IR software. This allows o complete the 8) characterization of the new ketocoumarins the ability of LFC3260 and LFC3220determined as (Figure quantifying the degree of polymerization and, nsitizers for an aminoketone (2-Methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, MPMP) therefore, the efficiency of the photoinitiator. If as evaluated. 80 not stated otherwise, the formulation always was 70 he test was performed by FT-IR in a clear formulation (bisphenol A epoxy diacrylate/silicone freshly prepared. 60 acrylate 99,5:0,5 by weight), with a concentration of PI at 4% and sensitizer at 0,5 by weight. An X400+ system equipped with a UV LED spot centered at 400nm (Excelitas) was used as light source. Through-Cure experiments. The 50 igure 8) photopolymerizable compositions for the test MPMP 40 were prepared by dissolving the photoinitiator MPMP + ITX 80 and co-initiator at the same concentration 30 MPMP + LFC 3260 by weight in a cyan inkjet ink. The ink was 20 70 MPMP + LFC3220 applied at a thickness of 6 microns, by a K101 control coater on a paper support. It was passed 10 60 under the light source, Phoseon LED 365 nm 0 (12 W/cm2) or Fusion DRSE-120 Q/QNL 0 0.5 1 1.5 2 2.5 3 3.5 4 50 Time [s] equipped with a Phoseon RX StarFire MAX MPMP UV Light Source 395 nm (4 W/cm2). The 40 FIGURE 8. Sensitization effect measurement by FT-IR at 400nm. MPMP + ITX photopolymerization rate is measured with the 2

3 days

10 days

% DB conversion at 1407 cm-1

% DB conversion at 1407 cm-1

after curing

30 20 10

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MPMP + LFC 3260

page 52 u

MPMP + LFC3220

UV+EB Technology • Issue 3, 2016 | 51


BEST PAPER t page 51

“Demand is increasing for the development of different photoinitiators with absorbtion in the 360 to 400 nm region, good photochemical activity, and low oxygen sensitivity and yellowing.” line rate (m/min) at which a complete photopolymerization occurs (through-cure). The photopolymerization is complete when the ink does not show any damage after repeated pressure and twists of the thumb on the surface. The higher the line rate to obtain through-cure, the higher the reactivity of the photoinitiator.

vs. blueness) by a color guide (45/0 BYK). The lower the b* value, the lower the yellowing of the sample. n

Yellowing. The photopolymerizable compositions for the test were prepared by dissolving the photoinitiator and the co-initiator at a concentration of 3% by weight in a clear inkjet ink. The ink was applied with a thickness of 6 microns, by a K101 control coater on a paper support, then passed twice under the light source [Phoseon LED 395 nm (16 W/cm2)] with a speed of 30 m/min. Yellowing was evaluated by measuring the b* value (yellowness

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References 1. Photoinitiators for UV LED, Lab Report Rahn AG, No. 2.02, June 2013. E. Knoevenagel, Ber Dtsch. Chem. Ges 31, 2596 (1898); Ibid. 37, 4461 (1904); E. Knoevenagel and S. Mottek, Ibid. 37, 4464 (1904); E. Knoevenagel and E. Langensiepen Ibid. 37, 4492 (1904); E. Knoevenagel and R. Arnot Ibid. 37, 4496 (1904); S.M. Sethna and N.M. Shah, Chem. Rev. 36, 1 (1945); L.L. Woods and M. Fooladi, J. Chem. Eng. Data 12, 624 (1967); D.P. Specht, P.A. Martic and S. Farid Tetrahedron 38, 1203 (1982).

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52 | UV+EB Technology • Issue 3, 2016

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SARTOMER PARTNERS You’re passionate about your formulations. We are, too. Our tech support team contributes ingenious chemistry to advance performance in a wide host of applications. Think electronics, soft-touch coatings and automotive adhesives, just to name a few. Formulators come to us for our unique expertise in acrylate and methacrylate chemistry. We lead the world with the broadest product portfolio for UV/EB/dual cure technology. But, it’s our interactive chemist-to-chemist support program that distinguishes us from the rest. Our technologists understand your needs and create customized and innovative solutions to reach your specific formulation, processing, and performance goals. Let’s formulate together.

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Industry News Sun Chemical Releases 2015 Sustainability Report Sun Chemical, Parsippany, New Jersey, released its 2015 Sustainability Report, which showcases Sun Chemical’s leadership in eco-efficiency through established data-driven metrics, as well as examples of how suppliers are contributing to the company’s environmental footprint. The report describes six case studies to show how Sun Chemical’s balanced scorecard approach is used to evaluate its suppliers’ environmental performance, helping to ensure that suppliers remain vigilant in developing new technology that reduces the overall environmental footprint of their products. Providing a report that shows the ongoing management and monitoring of key sustainability metrics is an important part of Sun Chemical’s sustainability policy. For more information, visit www.sunchemical.com. Miltec UV Partners with the University of Maryland Miltec UV, Stevensville, Maryland, announced the completion of a project for which it partnered with the University of Maryland QUEST Capstone Consulting Project. Honor students were tasked with developing a strategy to help Miltec UV choose a method of commercialization for its ceramic coating technology, a technique that is less expensive, safer and more effective than the current process used to manufacture lithium ion batteries. The team consisted of an electrical engineer, Katelyn Walter; a mechanical engineer, Austin Kendall; an accounting and finance honor student, Jessica Lewis; and a finance honor student, Tim Odukale. After evaluation of the financial implications and risks associated with multiple commercialization options, the recommendation was a dual-sided approach that allows Miltec to maximize profits while providing the flexibility to customize the strategy based on the customer’s needs. For more information, visit www.miltec. com. New UV/IR Product Catalog from Ushio Ushio America, Inc., Cypress, California, introduced its product catalog. It consists of the new UNIJET UV LED series, Laser Diodes, Excimer & XeFL, Germicidal, QIH IR Heater lamps, as well as UVB, Blacklight & Blacklight Blue, Industrial LED and Laboratory equipment. For more information, visit www.ushio. com. Toyo Ink Partners with KBA Toyo Ink Co., Ltd., Tokyo, Japan, a wholly owned subsidiary of the Toyo Ink Group, announced that it was chosen as the preferred global supplier of UV sheetfed offset inks to KBA-Sheetfed Solutions AG & Co. KG, a business unit of the Koenig & Bauer Group of Germany. The FLASH DRY™ series from Toyo Ink — the standard FLASH DRY™ Karton series, the energy-conserving FLASH DRY™ HS series and the FLASH DRY™ LED series will be the recommended UV inks for KBA-Sheetfed’s UV 54 | UV+EB Technology • Issue 3, 2016

presses. These three inks will continue to be available exclusively from the Toyo Ink Group’s dealer network. All UV presses in the KBA-Sheetfed customer and training center will print with Toyo FLASH DRY inks in the future. Under this partnership, both firms will promote the advantages of LED-UV offset technology for users and increase its market acceptance and implementation. For more information visit, www.toyoink.jp/en. Sartomer Opens New Facility Sartomer Americas, Exton, Pennsylvania, a business unit of Arkema Inc., opened a new center named the Discovery Hub. The facility, located in the company’s Exton, Pennsylvania office, will enhance collaboration with customers and enable stronger teamwork to address current and future chemical formulation challenges. The main section of the Discovery Hub is equipped with sleek furniture and three computer stations, which create an ideal space for casual meetings and collaboration. A glass-enclosed conference room offers more privacy and the ability to host larger gatherings. Vivid graphics on the wall help communicate the many innovative solutions that Sartomer has developed for its customers over the years. For more information, visit www.sartomer.com. Songwon and Heraeus Join Forces Songwon, Ulsan, Korea, and Heraeus, Hanau, Germany, signed a co-operation agreement to jointly develop and market high end specialty chemicals for the electronics industry. This new cooperation combines Songwon’s expertise in R&D and chemical manufacturing with Heraeus’ technical capabilities and reputation in the electronics chemical industry, thereby broadening both companies’ access to the global electronics market. Under the agreement, the high end specialty chemicals co-developed for the electronics and semiconductor market will be produced by Songwon and marketed by Heraeus along with its existing portfolio. For more information, visit www.heraeus.com or www. songwon.com. Dymax Releases New Selector Guide Dymax Oligomers & Coatings, Torrington, Connecticut, released an enhanced Bomar® Oligomers Selector Guide that streamlines product selection. The guide includes new products specifically developed to satisfy the performance requirements of emerging application technologies like uvebtechnology.com + radtech.org


Patent Profiles hydrophobic coatings, 3D printing inks and nail gel coatings. It offers manufacturers a complete system solution for their specific application, helping them choose the appropriate oligomer, compatible dispensing and curing equipment, as well as the option to use Dymax scaleup and manufacturing services. Extensive technical data on the company’s leading UV-cure oligomers are presented in this guide, simplifying the product selection process. For more information, visit www.dymax-oc.com or call 860.626.7006.

FACES

Sun Chemical, Parsippany, New Jersey, named Jeffrey Shaw as chief supply chain, quality and business improvement officer. In this role, Shaw will be responsible for optimizing Sun Chemical’s entire supply chain, from the purchase of raw materials and the scheduling of the company’s plants, to managing market-based stock levels and the shipping of finished products to customers worldwide. Sartomer Americas, a business unit of Arkema Inc., Exton, Pennsylvania, has named Jeff Prosser as senior account manager for Texas and the southeast US. In his new role, Prosser will help educate and connect customers in his region with innovative specialty chemical solutions that best serve their coatings, adhesives, inks, elastomers and other formulation needs. Walsh & Associates, Inc., St. Louis, Missouri, named Marcelo Zocchi as account manager in the Great Lakes region. Zocchi has held global management positions with several large US and European business including GE Plastics Europe, GE Silicones and most recently business development manager with ICM Products. APV Engineered Coatings, Akron, Ohio, added to its staff of coating chemistry professionals with the hire of Lon Bauer as product development manager. Bauer will be responsible for developing new coatings for flexible films and textiles, including development work on the company’s VYNGUARD® line of premium high-performance coatings. Steve Lapin retired from PCT Engineered Systems (now ebeam Technologies) on June 1, 2016. Lapin has been a member of RadTech since it was found in 1988 and also served on the Board and various committees within RadTech. Most recently, he has been the EB columnist for this publication. In his retirement, Lapin will work parttime as an independent consultant (SCLapin Consulting LLC, SCLapin@ gmail.com) and also in a business development role for Daybreak Technologies (www.daybrktech.com). n

uvebtechnology.com + radtech.org

Actinic radiation and moisture dual curable composition US Patent No. 9,315,695 Assignee: Dymax Corporation, Torrington, CT Abstract: A dual curable, liquid adhesive composition capable of polymerization by exposure to actinic radiation and moisture. The composition is particularly useful for liquid adhesives for electronic applications. The composition comprises an alkoxysilane functional polyurethane acrylate oligomer; a free radical polymerizable reactive diluent; a free radical photoinitiator; a catalyst for moisture curing of silane groups; and an optional alkoxysilane functional oligomer having a polyolefin group; an optional acrylate or methacrylate functional polyurethane acrylate oligomer; an optional hydroxyl terminated monoacrylate or monomethacrylate functional reactive diluent; an optional UV-absorber and hindered amine light stabilizer antioxidant; an optional wax capable of reducing oxygen inhibition; an optional 1,3 dicarbonyl compound chelating agent; an optional thixotropic agent; and an optional adhesion promoter. optional adhesion promoter. Sunlight Curable Coating Compositions US Patent No. 9,340,704 Assignee: Dymax Corporation, Torrington, CT Abstract: A coating composition capable of curing to a high hardness by exposure to sunlight. More particularly, the coating composition comprises a high molecular weight polyurethane (meth)acrylate or methacrylate dissolved in one or more nonalcohol solvent, a visible light photoinitiator, and an alcohol solubilizer. Method for forming multilayer coating film  US Patent No. 9,404,010 Assignee: KANSAI PAINT CO., LTD. (Hyogo, Japan)  Abstract: An object of the present invention is to provide a method for forming a multilayer coating film, capable of achieving excellent curability under low-temperature, short-time conditions, and forming a multilayer coating film having excellent chipping resistance and an excellent finished appearance. This method comprises sequentially applying an aqueous first colored coating composition (X), an aqueous second colored coating composition (Y), and a clear coating composition (Z) to a substrate, and simultaneously bake-curing the resulting multilayer coating film. In this method, the aqueous first colored coating composition (X) comprises an aqueous film-forming resin (A) and a specific blocked polyisocyanate compound (B), and the clear coating composition (Z) comprises a hydroxy-containing acrylic resin (K) having a hydroxy value in a specific range, a polyisocyanate compound (L), and an organometallic catalyst (M) containing a metal compound (M1) selected from a specific range and an amidine compound (M2). n

UV+EB Technology • Issue 3, 2016 | 55


BEST STUDENT PAPER By Sara M. Kaalberg and Julie L. P. Jessop, Department of Chemical & Biochemical Engineering, University of Iowa

Combining Oxiranes and Oxetanes to Enhance Kinetics and Improve Physical Properties Editors Note: The following received RadTech 2016’s Best Student Paper Award at the event held May 16-18 in Chicago, Illinois. Abstract ycloaliphatic epoxides (oxiranes) typically polymerize more slowly than acrylates and tend to be brittle. However, cationic active centers are long-lived, resulting in significant dark cure. Here, oxetane addition to formulations is correlated to improvements in polymerization kinetics and polymer properties during dark cure. Raman spectra yielded conversions; DMA provided Tg and crosslink density. Increasing oxetane concentrations improved epoxide conversion and drastically lowered Tg of the resulting polymers, thereby increasing the application range for cycloaliphatic epoxides.

C

Introduction Cationic photopolymerization offers unique advantages for many applications. For example, these systems are not inhibited by oxygen and are essentially nonterminating, leading to very long active-center lifetimes (hours or even weeks). In contrast, free radicals generally have propagating lifetimes on the order of seconds, due to rapid radical-radical termination reactions or oxygen- quenching reactions, both of which quickly consume the free-radical active centers. As a consequence of the long-lived active centers, cationic polymerization may proceed long after the irradiation has ceased, leading to dark cure or post-illumination polymerization. This dark cure results in further property development over the course of hours or days and is due to the active centers lasting long enough to be controlled by diffusion and having the ability to travel further away from the areas that were initially irradiated, both deeper into the coating and into areas that were never irradiated.1 The use of oxetanes in conjunction with epoxides (also known as oxiranes) has the potential to decrease chain transfer during polymerization and enhance physical properties. During ring-opening polymerization, the ring in the growing polymer chain is opened, while the attacking molecule remains intact, so the competition between the monomer and polymer is governed primarily by the nucleophilicity of the oxygen atom in cyclic and linear structures.2 Because epoxides and linear ethers have very similar pKa values (Figure 1), the active centers have almost equal affinity for both the unreacted monomer functional groups and the polymer chains.3 Thus, competition between the monomer and polymer chains is a problem in epoxide systems, and chain transfer to polymer is typical in cationic ring-opening polymerizations containing epoxides. Intramolecular reaction leads to cyclic monomers, while intermolecular reaction leads to segmental exchange, or “scrambling.”4 Both of these chain transfer reactions lead to broadening of the molecular weight distribution, which is not favorable. This research examines pKa = 2.0 2.1 3.6 3.7 the effects of combining oxetanes Ring Strain (kJ/mol) = 107 23 5 -114 and epoxides on the reactivity of each monomer, the overall reaction FIGURE 1. Relative nucleophilicities and ring strain of cyclic and kinetics, and the final physical linear ethers. 56 | UV+EB Technology • Issue 3, 2016

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Photonic Solutions Inc.) for 10 minutes at an effective irradiance of 710 mW/cm2 and measured with a radiometer (R2000, Omnicure, wavelength range 250nm – 1μm). Real-time Raman spectra were acquired FIGURE 2. Chemical structures for the monomers 3,4-epoxycyclohexylmethyl-3,4using a holographic epoxycyclohexane carboxylate (EEC, a); 3-ethyl-3-hydroxymethyl oxetane (OXA, b); 3-ethylprobe head (Mark II, 3-phenoxymethyl oxetane (POX, c); 3-ethyl-3-[(2- ethylhexyloxy)methyl] oxetane (EHOX. d); Kaiser Optical Systems 3-ethyl-3 (3-ethyloxetane-3-yl) methoxy methyl oxetane (DOX. e); and the diaryliodonium Inc.) with a singlehexafluoroantimonate photoinitiator (IFA, f). mode excitation fiber delivering ~220 mW properties of the polymer films, while reducing illumination time of 785-nm near-infrared laser intensity to the quartz capillary and exploiting dark cure in these systems. tubes. The spectra were collected with a 1-s exposure time and 3 accumulations. Additionally, spectra were taken at various time Experimental points after illumination had ceased to measure any conversion Materials increases and determine how each formulation affected dark To determine the effect of viscosity and oxetane structure cure over the course of hours and days. Dark cure was followed and functionality on the conversion of an industrially relevant for up to four hours after illumination ceased in 5- to 15-minute difunctional epoxide, a series of formulations was made increments. Conversions taken 24 to 72 hours after illumination containing varying mole percentages of the epoxide and four did not exceed an additional 5% conversion from the four-hour oxetanes (Figure 2). The comonomer formulations contained 0.5 measurements for any formulation. mol% diaryliodonium hexafluoroantimonate (IFA, Polyset) in mixtures of the highly viscous 3,4-epoxy-cyclohexylmethanyl 3,4- Conversion was calculated from the Raman spectra using epoxy- cyclohexanecarboxylate (EEC, Sigma Aldrich) and one of Equation 1. The epoxide reaction peak was measured at 790 cm-1, the four oxetanes. The oxetane side groups were a hydroxyl group the oxetane reaction peak at 1150 cm-1, and the reference peak (OXA), a phenyl group (POX), a branched carbon chain (EHOX), for both monomers at 1450 cm-1. This stable reference peak is or another oxetane (DOX). With respect to functionality, POX used to eliminate error due to baseline changes. In Equation 1, I(t) and EHOX are monofunctional oxetanes, DOX is difunctional, denotes the peak intensity at time t, and I(0) represents the initial and OXA has an intermediate functionality, since it contains one peak intensity. The subscripts denote whether the measurement is cyclic ether as well as a hydroxyl group that is able to react with a of the reaction peak intensity (rxn) or the reference peak intensity cationic active center through a chain transfer reaction. (ref). Methods Formulations and experimental variables Experiments were performed to determine effects of various formulation factors, including oxetane concentration, liquid monomer viscosity, and comonomer functionality. The oxetane concentration ranged from 0 mol% (i.e., 100% EEC) to 60 mol% (i.e., 40 mol% EEC) in increments of 20 mol%. Because oxetanes have significantly different viscosities and plasticizing ability in EEC, equal viscosity formulations of 200 cP and 300 cP were also compared for each of the oxetanes in EEC. Raman spectroscopy Raman spectroscopy was used to monitor simultaneously epoxide and oxetane conversion, both during UV illumination and at specific time intervals after the light had been shuttered (dark cure).5 Samples were injected into 1mm-ID quartz capillary tubes and illuminated with a mercury arc lamp fitted with a 250-450 nm filter (Acticure® Ultraviolet/Visible Spot Cure system, EXFO uvebtechnology.com + radtech.org

EQUATION 1.

Fractional

I(t)rxn ⁄ I(t)ref =1Conversion I(0)rxn ⁄ I(0)ref Dynamic mechanical analysis Dynamic mechanical analysis (DMA) was used to compare the glass transition temperature (Tg) and network homogeneity of neat EEC to formulations containing both epoxide and oxetane. The procedure has been described previously.6 DMA films were made by injecting the formulations between two microscope slides (separated by two cover slips) and photopolymerizing under a belt-driven Fusion curing system fitted with an H bulb with an effective irradiance of 180 mW/cm2, as measured with the radiometer. The films were passed at 8 ft/min under the lamp three times for each side. The resulting films were 0.30 mm in thickness and were cut into rectangles measuring approximately 20 x 5 mm. page 58 u UV+EB Technology • Issue 3, 2016 | 57


BEST STUDENT PAPER t page 57 TABLE 1. Comparison of glass transition temperatures and viscosities for neat monomers. Tg

Viscosity at 25°C

EEC

197°C

550 cP

EHOX

-60°C

5.0 cP

POX

1°C

14 cP

OXA

46°C

22 cP

DOX

51°C

13 cP

Each film was allowed to dark cure for multiple weeks to ensure a final room-temperature conversion before testing. As noted above, conversion increases were < 5% during this period of extended dark storage. Films were tested using the film tension clamp in the DMA (Q800, TA Instruments). Frequency sweep/temperature ramps for each film ranged from >30° C under the neat oxetane Tg (see Table 1) to 250° C (i.e., 50° C above the neat epoxide Tg) at a sinusoidal strain of 0.05% applied at a frequency of 1 Hz. Each film underwent two thermal cycles to determine if annealing was present and how it affected the Tg.

The neat oxetanes have long induction periods (on the order of minutes). Combining EEC with any of the oxetanes decreased the oxetane induction period and increased the conversion for both monomers in each formulation. The enhancement in oxetane reactivity stems from the epoxide functional groups acting as reactive sites for the initiation of the oxetane functional groups.7,8 For example, in the difunctional EEC/monofunctional POX formulation series, increasing the proportion of oxetane results in increased epoxide conversion (Figure 4) – both at the end of the illumination period (values along the y axis) and during dark cure. The impact of the epoxide on the kinetics of the oxetanes is more complex (Figure 5). For the neat monomer formulation, the reaction proceeds more slowly, with only 10% oxetane conversion occurring during illumination and a final oxetane conversion approaching 30% after three hours of dark cure. Compared to the neat oxetane, the epoxide/oxetane mixtures have higher oxetane conversions during illumination (> 15%), as well as faster polymerization and a reduced induction period (not shown in Figure 5), and final oxetane conversions are achieved much more rapidly in the dark (i.e., within one hour of shuttering the light).

Results and discussion Impact of dark cure on kinetic results The epoxide EEC generally shows low conversions in neat formulations (less than 10% during the first 10 minutes of illumination; less than 40% final conversion after four hours). Long illumination times are not required to get full property development or to speed the reaction, as the conversion profile is similar between a sample illuminated for four hours and one illuminated for 10 minutes and allowed to dark cure for four hours (Figure 3). Thus, once the cationic active centers have been generated, there is no need to continue illumination, and reduced energy costs are realized. However, a large proportion of monomer conversion and property development can occur in the time following illumination, and the impact of dark cure must be considered.

The other three oxetanes behave similarly (i.e., increased epoxide conversions result from increased proportions of oxetane in the formulation) to varying degrees. DOX, the difunctional oxetane, does not greatly enhance the epoxide conversion, although the dark-cure conversion of the oxetane greatly benefits from the presence of the epoxide (Figures 6 and 7). Neat DOX formulations achieve only 5% conversion by the end of the illumination period but show very high dark-cure conversion. Shorter illumination times at lower intensities result in longer induction periods, but as soon as the reaction reaches a threshold conversion, high conversions are obtained quickly. In contrast to neat DOX, a 40:60 EEC:DOX formulation reaches almost 70% oxetane conversion during the same 10-minute illumination period, and less conversion increases are seen post-illumination. DOX does not enhance epoxide conversion as much as the other oxetanes because the initial formulations are highly viscous and a heavily crosslinked network is formed upon illumination of the two difunctional monomers, which traps the active centers and limits A B reactive diffusion. The functionality FIGURE 3. EEC conversion as a function of time: (a) during the first 10 minutes of illumination and of the oxetane (b) during the subsequent 4 hours. The red line shows conversion for a sample that was illuminated monomer, therefore, during the entire period. The blue line shows conversion for a sample that was illuminated only for the must be considered first 10 minutes and then allowed to dark cure for the remaining 4 hours. The formulations contained when choosing 0.5 mol% of the photoinitiator IFA. 58 | UV+EB Technology • Issue 3, 2016

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from the first to second thermal cycle decreases (Figure 8). As the amount of POX increases, the formulation viscosity decreases, and higher conversions are attained for both EEC and POX prior to DMA measurements (Figures 4 and 5); therefore, less annealing is possible due to these advanced network restrictions. Even less annealing is observed for the EEC/DOX system, since both monomers are difunctional.

FIGURE 4. Epoxide conversion over time for EEC and POX post-illumination. Conversions immediately after illumination lie on the y-axis. The dashed line represents neat EEC (with 0.5 mol% photoinitiator).

Additionally, formulation viscosity affects the Tg but the extent depends on the comonomer. Equal viscosity formulations result in similar Tg changes from the first to second cycle, but the Tg values for formulations with the same viscosity can vary up to 20° C for the different oxetane comonomers. For example, in comparing 200 cP formulations of EEC/POX and EEC/DOX, each ΔTg was 6° C; however, the Tg for the first cycle of EEC/POX was 124° C, while EEC/DOX was 145° C. In these equimolar and equal viscosity studies on the physical properties of polymer films, monofunctional oxetanes are better able to lower viscosity and decrease the Tg of EEC, since difunctional oxetane monomers create a highly crosslinked network upon polymerization, causing them to be less effective in lowering the Tg. Conclusions Once cationic active centers are produced, continued illumination is not beneficial – reaction time and ultimate conversions after page 60 u

FIGURE 5. Oxetane conversion over time for EEC and POX post-illumination. Conversions immediately after illumination lie on the y-axis. The dotted line represents neat POX (with 0.5 mol% photoinitiator). the comonomer for polymerization with EEC. Monofunctional oxetanes enhance the kinetics and conversion of EEC to a higher degree than difunctional oxetanes, reducing the need to illuminate for long periods of time and to wait for physical property development post-illumination. Impact of Oxetane Addition on Tg. Two thermal cycles were necessary for most formulations due to the long-lived nature of cationic active centers.9 The addition of oxetanes has the potential to greatly reduce the Tg of a copolymer film by up to 100° C, resulting in films that are much less brittle than neat EEC. The second thermal cycle resulted in Tg increases of 5° C for EEC, demonstrating that some reaction occurs during the first cycle, which incorporates additional monomer into the polymer matrix. The amount of annealing in the copolymer that occurs during the first thermal cycle depends on both the epoxideoxetane formation ratio and the oxetane monomer structure. For example, as the amount of POX is increased, the change in Tg uvebtechnology.com + radtech.org

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UV+EB Technology • Issue 3, 2016 | 59


BEST STUDENT PAPER t page 59

FIGURE 6. Epoxide conversion over time for EEC and DOX post-illumination. Conversions immediately after illumination lie on the y-axis. The dashed line represents neat EEC (with 0.5 mol% photoinitiator). FIGURE 8. Tg for first and second thermal cycle for EEC:POX formulations, 80:20, 90:10, and 95:5 (left to right), plotted as a function of solution viscosity. For each formulation, the first thermal cycle has a lower Tg than second cycle (first on top, second on bottom). Cooperative Research Center. We would like to thank Changzhou Tronly New Electronic Materials, Toagosei and Polyset for their generous donation of materials.

FIGURE 7. Oxetane conversion over time for EEC and DOX post-illumination. Conversions immediately after illumination lie on the y-axis. The dotted line represents neat DOX (with 0.5 mol% photoinitiator). dark cure are similar to those after full illumination periods. In fact, most EEC conversion and its corresponding polymer property development can occur during this dark cure period, which results in lower energy requirements. However, the time required to reach these ultimate properties in EEC is still long (on the order of hours). Combining epoxides and oxetanes greatly increases kinetics for both monomers, lowering illumination time and dark cure needed to reach final polymer properties. In the series of comonomer formulations examined here, increasing the proportion of oxetane in the formulation resulted in acceleration of the EEC polymerization and lowering of the final polymer Tg. Monofunctional oxetanes were more effective than multifunctional oxetanes in realizing these benefits due to lower initial viscosities and less restricted network formation. n Acknowledgements This material is based on work supported by the Fundamentals & Applications of Photopolymerizations Industry/University 60 | UV+EB Technology • Issue 3, 2016

References 1. Ficek, B.A.; Thiesen, A.M.; and Scranton, A.B. Cationic photopolymerizations of thick polymer systems: Active center lifetime and mobility. Eur. Polym. J. 2008; 44(1):98-105. doi:10.1016/j.eurpolymj.2007.10.023. 2. Sasaki, H.; Rudzinski, J.M.; and Kakuchi, T. Photoinitiated cationic polymerization of oxetane formulated with oxirane. .J Polym. Sci. Part A Polym. Chem. 1995; 33(11):1807-1816. doi:10.1002/ pola.1995.080331107. 3. Kubisa, P. 4.08 - Cationic Ring-Opening Polymerization of Cyclic Ethers. Vol 4. Elsevier, B.V.; 2012. doi:http://dx.doi.org/10.1016/ B978-0-444-53349-4.00102-3. 4. Kubisa, P.; Penczek, S. Cationic activated monomer polymerization of heterocyclic monomers. Prog. Polym. Sci. 1999; 24(10):14091437. doi:10.1016/S0079-6700(99)00028-3. 5. Cai, Y.; Jessop, J.L.P. Decreased oxygen inhibition in photopolymerized acrylate/epoxide hybrid polymer coatings as demonstrated by Raman spectroscopy. Polymer (Guildf). 2006; 47(19):6560-6566. doi:10.1016/j.polymer.2006.07.031. 6. Dillman, B.; Jessop, J.L.P. Dillman [2013] Cationic CTAs.pdf. J. Polym. Sci., Part A Polym. Chem. 2013; 51:2058- 2067. 7. Crivello, J.V. “Kick-Starting” Oxetane Photopolymerizations. J. Polym. Sci., Part A Polym. Chem. 2014;52(20):2934-2946. doi:10.1002/pola.27329. 8. Crivello, J. V. Investigations of the reactivity of “kick-started” oxetanes in photoinitiated cationic polymerization. J. Polym. Sci., Part A Polym. Chem. 2014; 53(4):586-593. doi:10.1002/pola.27479. 9. Sipani, V.; Scranton, A.B. Dark-cure studies of cationic photopolymerizations of epoxides: Characterization of the active center lifetime and kinetic rate constants. J. Polym. Sci., Part A Polym. Chem. 2003; 41(13):2064- 2072. doi:10.1002/pola.10750. uvebtechnology.com + radtech.org


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Regulatory News

Doreen M. Monteleone, Ph.D., director of sustainability & EHS initiatives, RadTech International North America doreen@ radtech.org

Lautenberg Chemical Safety for the 21st Century Act Becomes Law The Frank R. Lautenberg Chemical Safety for the 21st Century Act overhauls the Toxic Substances Control Act (TSCA) (https://www.congress.gov/bill/114th-congress/house-bill/2576). The Lautenberg Act makes many significant changes to TSCA, including the following: • Requiring the US Environmental Protection Agency (US EPA) to evaluate chemicals (both new and existing) to determine whether they present an “unreasonable risk of injury to health or the environment under the conditions of use” • Prohibiting consideration of costs or other non-risks factors in chemical evaluations • Requiring consideration of potentially exposed or susceptible subpopulations in evaluating chemicals • Allowing chemical manufacturers to ask US EPA to evaluate a chemical • Giving US EPA the authority to issue administrative orders to require testing of chemical • Requiring US EPA to reduce the use of vertebrate animals in testing • Eliminating the “least burdensome” requirement for chemical regulations, making it easier for US EPA to restrict – or ban – chemicals • Preempting state chemical regulations under certain conditions • Limiting confidential business information (CBI) claims/allowing US EPA to share CBI with states • Allowing US EPA to charge higher fees for chemical reviews RadTech hosted a webinar on this topic which has been archived at http:/www.esf.edu/outreach/radcuring/ webinar.htm#Marrapese2. Ozone Implementation Act Earlier this year, 114th Congress passed H.R. 4775 – Ozone Standards Implementation Act (OSIA) of 2016 (https://www.congress.gov/bill/114th-congress/house-bill/4775). The bill amends the Clean Air Act by revising the National Ambient Air Quality Standards (NAAQS) program. It extends the deadline for states to submit designations to implement the 2015 ozone NAAQS until Oct. 26, 2024. In addition, the deadline for US EPA to designate state areas as attainment, nonattainment or unclassifiable areas with respect to the 2015 ozone NAAQS was extended to Oct. 26, 2025. The bill also changed the review cycle for criteria pollutant NAAQS from five years to 10 years. US EPA Announces National Enforcement Initiatives US EPA announced its National Enforcement Initiatives (NEIs) for fiscal years 2017 through 2019. The Agency added two relevant new enforcement initiatives and expanded one existing initiative. The first new enforcement initiative, “Reducing Risks of Accidental Releases at Industrial and Chemical Facilities,” reduces the risk of catastrophic accidents at facilities that make, use and store extremely hazardous substances. This initiative dovetails with US EPA’s proposed revisions to the Risk Management Rule under the Clean Air Act, which was published in the Federal Register on March 14, 2016. With the second new enforcement initiative, “Keeping Industrial Pollutants Out of the Nation’s Waters,” US EPA will focus on wastewater discharges from chemical and metal manufacturing, mining and food processing facilities. Priorities will be driven by data submitted pursuant to Clean Water Act discharge permits and other sources. Learn more at https://www.epa.gov/enforcement/national-enforcement-initiatives. OSHA Updates Eye and Face Protection Standards in Final Rule The Occupational Safety and Health Administration (OSHA) published a final rule that became effective on April 25, 2016, and updated requirements for personal protective equipment (PPE) for workers in general industry. The rule reflects current national consensus standards and ensures that workers can use up-to-date eye and face protection. It updates references in OSHA’s Eye and Face Protection Standards to recognize the ANSI/ISEA Z87.1-2010, Occupational and Educational Personal Eye and Face Protection Devices, while deleting the outdated 1986 edition of that same national consensus standard. OSHA also is retaining the 2003 and 1989 (R-1998) versions of the ANSI standard already referenced in its standard. In addition, the final rule updates the construction standard by deleting the 1968 version of the ANSI standard that was referenced and now includes the three ANSI standards referenced above to ensure consistency. The rule can be found at https://www.federalregister.gov/articles/2016/03/25/2016-06359/updating-oshastandards-based-on-national-consensus-standards-eye-and-face-protection.

62 | UV+EB Technology • Issue 3, 2016

uvebtechnology.com + radtech.org


Regulatory News News from the West Coast

Permit Streamlining for UV/EB At a recent meeting of the South Coast Air Quality Management District (SCAQMD) board, several board members requested a report from staff regarding the status of the agency’s permit application backlog. Shortly thereafter, the acting executive officer announced a reorganization of his executive staff to improve the agency’s operational efficiency, as well as its responsiveness to community and regulated interests. Rita Loof, director of regional environmental affairs, RadTech International North America rita@radtech.org

A newly appointed permitting chief led a meeting of the Permit Streamlining Task Force to get feedback from stakeholders and present proposed changes to make permitting more efficient. Policy Explores Regulatory Certainty The South Coast Air Quality Management District formed the “Ad Hoc Committee on Large Compliance Investments and Future Regulatory Certainty” to look for ways the agency can provide more regulatory certainty to the regulated community. The RadTech Association was asked to serve as an advisor to the committee. The project focuses on avoiding stranded assets for businesses complying with SCAQMD rules, reducing risks and increasing incentives for voluntary and required adoption of clean air technologies. Board members had expressed concern that the agency needs to be able to honor investments or compensate business owners if the rule changes. The issue of regulatory “taking” (a term derived from the just compensation clause of the Fifth Amendment of the US Constitution) is being considered. A recently released draft policy included various concepts such as: • Working with trade associations and industry groups to better understand the limitations of small and large businesses in acquiring and financing equipment. • Identifying and offering incentives for facility modernization for early replacement or retrofit of equipment. According to staff, incentives can minimize the upfront costs while accelerating the adoption of cleaner technologies. SCAQMD staff will explore funding opportunities, including the possible creation of grant and incentive programs, to help businesses adopt cleaner technology. In addition, SCAQMD staff will work with state and federal loan guarantee programs to ease financial constraints where possible. • Considering additional permit exemptions in SCAQMD Rule 219 for low-emitting equipment and processes. BPA in California Update Effective May 2016, changes to California’s Proposition 65 will require businesses to provide warnings for products that expose Californians to “significant amounts” of Bisphenol-A (BPA). Proposition 65 was enacted in 1986, and it is the state’s toxic chemical right-to-know law, listing approximately 800 chemicals. Last year, the state’s Developmental and Reproductive Toxicant Identification Committee (a group of scientists appointed by the Governor) unanimously determined that BPA clearly was shown to cause female reproductive toxicity and added BPA to California’s Proposition 65 list. The American Chemistry Council said, “We strongly disagree with the DART-IC decision to list BPA under Proposition 65 as a female reproductive toxicant. The decision is not supported by the extensive scientific record presented to the committee and is completely contrary to explicit input provided by the US Food and Drug Administration (FDA). In April, FDA’s acting chief scientist submitted a letter to the DART-IC stating that the results of FDA’s own comprehensive research ‘do not support BPA as a reproductive toxicant’.” The organization filed a lawsuit in 2013 and obtained a court order to compel the state’s Office of Environmental Health Hazard Assessment (OEHHA) to remove BPA from its Proposition 65 list. In 2014, a Sacramento County Superior Court judge ruled that the industry’s opposition was “misinformed and confused.” BPA received an exception that allows generic warnings near cash registers rather than on the products themselves, but do not specifically tell consumers which products contain the chemical. The state’s new warning reads as follows: “Many food and beverage cans have linings containing bisphenol A (BPA), a chemical known to the State of California to cause harm to the female reproductive system. Jar lids and bottle lids also may contain BPA. You can be exposed to BPA when you consume foods or beverages packaged in these containers.” n

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UV+EB Technology • Issue 3, 2016 | 63


Calendar SEPTEMBER

7-9 RadTech China Annual Conference, Anqing County Garden Phoenix Hotel, Anqing City, Anhui Province, China. For more information, visit radtechchina.com. 13 Sustainability Conference, held in conjunction with SGIA, Las Vegas, Nevada. For more information, visit http://2016conference.sgiapartnership.org/. 13-15 Labelexpo Americas 2016, Donald E. Stephens Convention Center, Rosemont, Illinois. For more information, visit labelexpo-americas.com.

OCTOBER

5-6 The Inkjet Conference, Düsseldorf/Neuss, Germany. For more information, visit theijc.org. 24-27 RadTech Asia 2016, Hilton Tokyo Odaiba, Tokyo, Japan. For more information, visit radtech-asia.org.

NOVEMBER

2-3 RadTech Fall Meeting, Hilton Garden Inn Austin Downtown/Convention Center, Austin, Texas. For more information, visit radtech.org.

14-16 SGIA, Las Vegas Convention Center-Central Hall, Las Vegas, Nevada. For more information, visit sgia.org. 25-28 GRAPH EXPO 16, Orange County Convention Center-North, Orlando, Florida. For more information, visit graphexpo.com.

Advertisers’ Index Alberdingk Boley....................................................................... alberdingkusa.com.................................................................................................. 9 American Ultraviolet.................................................................. auvcosolutions.com.............................................................................................. 23 A.W.T. World Trade Inc.............................................................. awt-gpi.com........................................................................................................... 59 BASF........................................................................................... basf.us/dpsolutions....................................................................Inside Front Cover Collins Inkjet............................................................................... collinsinkjet.com.................................................................................................... 21 EIT Instrument Markets............................................................. eit.com................................................................................................................... 52 Excelitas Technologies.............................................................. excelitas.com..........................................................................................Back Cover GEW............................................................................................ gewuv.com............................................................................................................... 7 GRAPH EXPO 16........................................................................ graphexpo.com..................................................................................................... 61 Heraeus Noblelight America LLC............................................ heraeus-noblelight.com....................................................................................... 25 Honle UV America Inc............................................................... honleuv.com............................................................................................................ 5 ICE USA 2017............................................................................. ice-x-usa.com......................................................................................................... 15 IGM Resins................................................................................. igmresins.com/contact...............................................................Inside Back Cover Labelexpo Americas 2016......................................................... labelexpo-americas.com...................................................................................... 34 Miwon Specialty Chemical Co., Ltd......................................... miramer.com.......................................................................................................... 47 Phoseon Technology................................................................. phoseon.com......................................................................................................... 19 RAHN-Group.............................................................................. rahn-group.com...................................................................................................... 1 Sartomer Arkema Group........................................................... sartomer.com......................................................................................................... 53 SGIA 2016................................................................................... sgiaexpo.org.......................................................................................................... 48 Siltech Corporation................................................................... siltech.com............................................................................................................. 30

64 | UV+EB Technology • Issue 3, 2016

uvebtechnology.com + radtech.org


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UV + ED Technology Issue 3 2016  

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