The art of manufacturing rollsurface mould components Gary A. Jacobsen President/ Chief Engineer of Jacobsen Lenticular Tool & Cylinder Engraving Technologies Company (JacoTech) of Itasca, Illinois, US, says the firm provides scientific solutions for the development and production of opticallybased cylindrical polymer/ plastic materials processing, including the manufacturing of micro-structured opticalquality roll-surface mould components used for the management and control of light.
The engraved units can be relatively small to unusually large and heavy
he focus of JacoTech’s custom optical micro-machining business is the ultra-precision CNC diamond turning, milling, and fly-cutting of cylindrical drums, rolls and mandrels used to extrude/emboss/cast or calendar plastic and polymer-based sheet and roll films and materials. The engraved units can be relatively small to unusually large (1,060 mm outer diameter by 4,500 mm wide) and heavy weight (2,300 kg). These optical-grade engraved cylinder processing moulds can contain simple to complex geometrical patterns designed to perform a number of complicated light management control functions. Using its custom-designed, precision large-scaled diamond turning equipment, JacoTech engraves complex optical patterns into materials such as copper, aluminium, electrolytic and electroless nickel alloys, beryllium copper, brass, gold and more. JacoTech’s diamond-machined geometries can include plano, spherical, parabolic, general aspheric, toroidal, hyperbolic, elliptical, cylindrical shapes and more. Special custom JacoTech cylindrical diamond engraving machining features can also include concave (sunken) or convex (raised) optical lens structures (one example: three-sided microsized cubic corner pyramids); in addition to angular, skewed, and circular patterns (one example: radial Fresnel lens), and many more. A typical drum during the engraving process where the engraved portion is shown beyond the mirror-surfaced portion of the drum yet to be engraved
Best results from proper designs To obtain the best results from a wellmanufactured cylindrically-engraved mould, a proper optical lens design is required to enable optically-based sheet films and materials to perform optimally for a client’s chosen resin and final end product. JacoTech offers complete optical engineering and lens design services for lenticular lenses and other complex micro-structured plastic optical lenses, as well as lens system optimisation, diamond tool designing and full metrology. For over a decade, the company has concentrated on improving the industry’s quality of 3D-animated/motion lenticular, produced by rotary web and sheet fed, via: offset, flexo, gravure, letterpress print processes and for digitally-imaged display products used by lenticular speciality printers. In order to accomplish this, an improvement over prior optical lens designs, diamond tooling and lenticular engraved cylinder mould processing were required to meet the everincreasing requirements of world-class producers of extruded lenticular sheets. An example of such an improvement is JacoTech’s ability to provide superior, ultra-low surface-waviness lenticular lens in its engraved cylinder moulds as compared to standard manufactured engraved cylinders. A second example is customised shaping of the lenticular lens surface profile, which creates much sharper, clearer, lower crosstalk, and greater apparent depth 3D-animated/motion lenticular printed/imaged products.
Advertorial Moulds for non-imaging applications JacoTech also produces cylindrical moulds for nonimaging applications. Fabrication of these direct machined moulds is intricate and time consuming. The plastic processing industry continues to seek improvement in lowering its manufacturing costs and improving profit margins for high-volume plastic/polymer produced products such as retroreflective vehicle license plates and road/traffic signage using three-sided cornercube prismatic reflective materials. JacoTech created a unique method of direct engraving precision corner cubic pyramids into cylinders that can be used to create prismatic materials in web roll form at near full processing line speeds. The material manufacturing cost saving of using recent new advanced prismatic web roll production vs. prior art of costly and slow injection moulding and similar one-by-one piece production methods can be dramatically impressive. Representative engraving is shown here where the lands between the grooves are razor sharp, although the size of the lands can be sized as desired by the client
JacoTech’s products are highly competitive and arguably set the quality and performance standard for these types of moulds. Such highly specialised custom engraved cylinders require essentially defect-free engraving in materials that yield a long life cycle. The cost of the mould is not the dominant cost element for customers when compared to the entire processing cost that occurs downstream in facilities. For over a decade, company owner, chief engineer and CEO, Dr Gary A. Jacobsen and his optical colleague, Dr R Barry Johnson, have worked together closely with a variety of technology experts to elevate the myriad of manufacturing and processing technologies necessary to achieve the finest quality optical engraved cylindrical drums, made available for global wide market use. This includes new diamond tooling shapes and structures, new hybrid CNC micro-diamond machine turning/milling/fly-cutting techniques, and creation of JacoTech’s own custom specifications for optical based copper and nickel/alloy plating to enhance achievement of the critical precision necessary for optical engraved patterns. Once all the new unique elements were brought together, they were tested and approved for use by a US-based extrusion leader in lenticular sheet and roll production. As a result of the R&D efforts, several US patents have been granted and issued, and are practiced today, in addition to being used with closely guarded trade secrets. Today, JacoTech ships custom opticallybased engraved cylinders around the globe for application
in many different industries. These significant efforts and investments have resulted in the achievement of world-class quality and market acceptance by companies throughout the world. For those interested in learning more about recent advances in lenticular technology, suggested readings are: R. Barry Johnson and Gary A. Jacobsen, “Advances in Lenticular Lens Arrays for Visual Display,” Proc. SPIE, Vol. 5874, DOI: 10.1117/12.618082; “Current Developments in Lens Design and Optical Engineering VI”, Pantazis Z. Mouroulis; Warren Smith; R. Barry Johnson, Editors, 587408 (2005). For competition reasons and to gain more market share, JacoTech customers seek to offer their plastic processed sheet and roll products to their end customers at the best possible price. In today’s environment, clients pay close attention to the dynamic changes in raw resin prices, and often then the lenticular extruders ask JacoTech for new optical lens designs and engraved cylinders for process modification. Today, as example, many extruders are moving away from using PET and towards selecting lower-priced resins such as PVC or PP. JacoTech’s manufacturing facility is located in the suburban Chicago area with close proximity to Chicago O’Hare International Airport. The 22,000 sq ft facility is a secured closed shop, to do highly specialised and confidential projects that the company produces for government and high profile US and global corporate accounts. Since we are not a volume based production company, but a one-part-at-a-time custom mould producer, our capacity output is not a problem. Having several custom large size and weight capable diamond turning/milling/fly-cutting machining centres enables JacoTech adequate back up and production machine time to meet customer schedule requirements. To enable "value added" offers to our customers, we continually push the envelope to the limits of technology and pattern designs by way of our own internal testing with live production utilising small-scale JacoTech test engraving cylinders. This continual R&D development lets us keep up with the ever changing demands of international standards compliance for optical based light management matters. JacoTech is continually evolving and expanding yearto-year as a consequence of new emerging optically-based plastics market opportunities. Since JacoTech is proactive rather than being reactive, it has plans for machinery enhancements and custom machine additions; including a new advanced roll plating facility; and added plans for additional international sales offices to help better serve the speciality optical plastic processing industries. A four-sided pyramidal structure (1.25 mm height) made by JacoTech OCTOBER 2013
IMA October 2013 Feature-Jacotech