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MCPL

Technical Presentation 15/11/98

ECONOMICALLY & ECOLOGICALLY IMPROVED PEROXIDE BLEACH MODHERA CHEMICALS PVT. LTD., offers “MODSCOUR-BL” as a product which is well tried and tested in hydrogen peroxide bleaching. The most distinguished properties of this product lie in that it enables various functions to be performed in one bath and also allow the fundamental needs of the consumers for more environmental compatibility. It is bio-degradable to high degree. Besides preventing redeposition of impurities the product offers good stability against acids (important for acid extraction) and alkalies, excellent wetting and re-wetting properties, inhibition of iron and stabilising action for peroxide. MODSCOUR-BL is suited for all types of machinery (continues and discontinuous) and guarantees minimal fibre damage, while achieving a high degree of whiteness at the same time. The user will benefit in quality from the universal means of applying this hitech MCPL product, and will also have savings in time, water and energy. Advantages: ☛ Only one product now needed for peroxide bleaching ☛ Optimum degree of whiteness ☛ Reduced use of chemicals possible ☛ Excellent d.p. values ☛ Very good re-wetability ☛ Suitable for all types of machines and processes ☛ Stable to acids, alkali, electrolytes and temperatures upto 135ºC ☛ Energy saving due to shortened processes ☛ Complete dispensation of silicate ☛ Biodegradable Scope of Applications:  Bleach bath stabilisation  Demineralisation bleaching by one bath / two step process  “Three in one” product - Wetting / scouring - Dispersing - Stabilisation


Profile of MODSCOUR-BL Good Biodegradibility

Sequestration of Ca, Mg at the presence of high amount of alkali

Stable to alkali, acids, electrolytes.

Sequestration of iron & other heavy metal ions in hot strongly alkaline liquors

Stable to temperatures upto 135ยบC MODSCOUR-BL

Support of surface active componet during extraction processes.

Dispersing power of Ca, Mg & heavy metal hydroxides

Acid extraction & peroxide bleaching in one bath

Easily dosable

Stabilisation by complete dispensation of silicate


mg metal ions / g product

MODSCOUR-BL : Manganese, Iron, Copper binding capacity at 98ยบC.

400 300

pH 7 pH 9 pH 11

200 100 0 manganese

iron

copper

Metal Ions

Stabilisation with MODSCOUR-BL in relation to magnesium content 100 90

Residual H2O2, (%)

80 70 60

Mod scour- BL

50

Perostab -BLN Silicate

40 30 20 10 0

Additio n o f M agn esium C hlo rid e [ยบd H]


Dependance of Stabilisation on the Magnesium content of the Bath

80 70 60 50 40 30 20 10 0

Modscour- BL

80ºdH

64ºdH

48ºdH

32ºdH

20ºdH

16ºdH

12ºdH

8ºdH

4ºdH

Waterglass 2ºdH

Final Stabilisation Residual Peroxide in %

90

Addition of Magnesium Chloride [ºdH]

BLEACHING OF TOWELLING Machine Material Liquor ratio

: : :

Thies Roto Stream 100% cotton 1 : 10


Bleaching recipe: 1~1.5 g/l : 2 g/l : 5~5.5 m/l : Water hardness : 8º Gh = 10ºEh (If only deionized water is available add 95°C

MODSCOUR-BL NaOH Flakes H2O2 50% 0.3 g/l MgCl2 . 6H2O)

60 min.

95°C

2.5°C/min. 80°C 25°C

Drain

Pretreatment of Dyeing - Cheese

Production Steps 1. Demineralization / Bleaching (Semi White) 2. Vat Dyeing 3. Reactive dyeing Problematic Repeatly unlevelness on light Vat and Reactive shades occurred in the past in so far as the package inside was lighter than outside. Analyses of the yarn led to the result that deposits of mineral hydroxides caused a blockage of the liquor flow.

The followimg Pre-treatment process solved the problem.


1.

1.1

1.2

Pre-Bleach Process Machine

:

Material Liquor ratio

: :

First Step Deminerlization 2 g/l : 5 g/l : 1 ml/l acetic acid 60% : 20 min, at 40°C

Open Thied package bleaching unit, circulation in one Direction, Inside Outside 300 kgs. cotton cheese, Nm 19/1. 1 : 10

MODSCOUR-BL ALTRANOL-OL / MODFOR-R-610 pH 4~6

Second Step (same bath) Bleaching 1.2 ml.l NaOH 50% 2 ml/l H2O2 35% 40 min. 95°C

40°C

-

2.

95°C

Drain

Overflow Rise at 70°C, 15 min. Rise at 70°C, 8 min. Addition of 1 g/l MODSCOUR-BL pH after Rinsing 7

Vat Dyeing (on different machine, closed apparatus with alternating circulation)


2.1

2.2 -

Pigmentation 1 g/l 1 g/l 0.25% 0.061% 5 m/l -10 min. at 80°C

MODQUEST-FSN MODLEVELLER-VL Pigment (Fine dispersion) Pigment (Colloidal) NaOH

Vatting 3~3.5 g/l 20 min. at 80°C 30 min. at 60°C

Sodium hydrosulphite

2.3

Rinsing and Oxidation

2.4

Soaping 1~1.5 g/l 1~1.5 g/l 15 min. at 96°C

MODLEVELLER-VL MODQUEST-WS

Acidification 0.5 ml/l 10 min. at 40°C

Acetic acid 60%

2.5 2.6

Rinsing at 40°C, and cold

2.7

Softening

2.8

Pressure drying

3. 3.1 3.2

Reactive Dyeing Pre-Bleach, same as for Vats Dye Process


% shade required 1~1.5 g/l 50 g/l 20 g/l 50°C

25°C

Reactive dye MODQUEST-FSN Glauber’s salt Soda ash 30 min.

50°C

60 min.

50°C

25°C Soda ash

Drain

MODQUEST-FSN Dyestuff Salt 3.2 3.4 3.5 3.6

3.7

Rinsing 5 min. at 25°C 5 min. at 25°C 5 min. at 25°C, addition of 0.4 ml/l Acetic acid 60% Washing-off 10 min. at 98°C addition of 1~2 g/l MODQUEST-FSN Rinsing 5 min. at 40°C After treatment 0.5 ml/l Acetic acid 60% 2% ECOFIX-2F 10 min. at 40°C Pressure drying

Bleaching of viscose with MODSCOUR-BL on MCS continuous machine


Method

:

Machine

:

Recipe  Desizing

: :

BLEACHING:  Starting recipe

 A)

 Desizing (Enzymatic)  Hydrozen Peroxide treatment MCS continuous machine - About 1000 running meters in the machine - Speed : 35 m/min. - Liquor ratio : 1:4 - Fabric: Viscose/Cosa about 10.000 running meters -

MODSCOUR-BL Enzyme pH Retention time

: : :

0.2~0.5 g/l As per recommendation As per recommendation : 12 h

- MODSCOUR-BL 1 g/l - NaOH 50% 1 g/l - H2O2 50% 4 g/l If only soft water is available add 0.6 g/l MgCl2,

Feed liquor conc. - Machinery : see sketch next page 12 g/l Enzymes } 4 g/l MODSCOUR-BL } pH=6 }

B)

20 g/lNaOH 50% } 3 g/l MODSCOUR-BL }

C)

40 g/lH2O2 50% } 4 g/l MODSCOUR-BL } 3 g/l MgCl2 }

500 ltr. Stock solutions ⇓ Dosage: 80 ltr./hr.

otherwise add only 0.2 g/l MgCl2.


Classical Procedure

Indicative formulation with MODSCOUR-BL

4 g/l Washing agent 10 – 12 g/l MODSCOUR-BL 1 g/l Phosphonate 0.2 g/l Magnesium Chloride 6 g/l Wetting agent 15 g/l NaOH 100% 6 g/l Stabiliser 50 g/l H2O2 35% 25 g/l NaOH 50% 40 g/lH2O2 50% ---------------------------------------------- Retention 18 – 24 h ------------------------------------------Squeezing effect 75% Squeezing effect 75%

Impregnation

Retention

Washing

COLD PAD-BATCH


LABORATORY TESTS Degree of whiteness Whiteness (Berger) Grey fabric MCPL Bleaching

63.9 70.8

Degree of polymerization (repeated determinations) 329 227

Rewettability

20 sec. Spontaneous

PRE-TREATMENT COMBINED ALKALI TREATMENT + OXIDATIVE DESIZING AND BLEACHING Machinery (see sketch next page) 1. Grey fabric (A-frame) 2. Singeing 3. Alkali treatment + oxidative deszing Padding liquor: Caustic soda 35 g/l Na-persulphate 5 g/l Altranol-CD/Modscour-LF 2 g/l Temperature 90-95°C Pick-up 80% 4. Dwelling 4 hours 5. Washing-off, 4 comparments at90°C – counter current, 1 compartment cold rinse 6. Impregnation compartment Starting concentration: Hydrogenperoxide 50% 40 ml/l Caustic soda flakes 28 g/l MODSCOUR-BL 10 g/l Magnesium chloride.6H2O 0.2 g/l 7. U-Box Reaction Unit Temp. of steam 101°C Steaming time 20 min 8. Washing-off compartments, Temp. 80-90°C 9. Drying cylinders


CONTINUOUS PRE-TREATMENT, 2 STEP PROCESS a) Alkali treatment + Oxidative desizing b) Bleaching

------>

1

2

7

3

4

5

8

6

9


Information about the process run 1.

Material

Cotton weave, 440 g per running meter Warp, sized with a blend of Corn starch Polyvinyl alcohol Polyacrylate Wax

2.

Previous process 1st Step: 2nd Step: 3rd Step:

3.

Enzymatic desizing, dwelling process a) Washing-off decomposed starch b) Alkali-Pad Steam Peroxide-Pad steam

Process 1st Step: 2nd Step:

Combined alkali + oxidative treatment, dwelling process a) Washing-off solubilized impurities and decomposed starch b) Peroxide-Pad steam 3.1 Advantages of the oxidative desizing in the alkali step - Maximum swelling of cellulose, breaking up of husks, saponification of waxes and grease. - Persulphate decomposes starch as well as polyvinyl alcohol - Alkali solubilizes polyacrylate - Shorter dwell time (4 hours) as compared to enzymatic desizing Remarks : Padding at 90ÂşC, covering of batching roller with foil Temperature is kept due to exothermic reactions: Starch + Persulphate exothermic > Polyvinylalcohol + Persulphate exothermic > 3.2

Calculation of feed liquor concentration F1 = 60% (Entry mangle) F2 = 90% (Exit mangle) 2 d = 30% 90 F2 – F1

= 90 = factor 3 90-60


4.

Results Degree of Polymerization 1820

Grey fabric Treated fabric (without Mercerization) No optical brightening 5.

1550

Damage factor by Eisenhut

Degree of Whiteness Elrepho Filter 48.9%

0.29

70%

Evaluation and actions The reduction of polymerization degree of 15% and a damage factor of 0.29 are satisfactory results. Bearing in mind that the former practised enzymatic desizing resulted in an incomplete removal of the size the oxidative method is a good alternative. Pad-steam (U-box) continuous oxidative desizing and bleaching Process-steps

A:

3 Compartments prescouring 90-95ยบC Recipe 1 Addition into compartment No. 3, with overflow in compartment No. 2 and No.1 0.5 ~ 1g/l 1 g/l

ALTRANOL-CD/MODSCOUR-LF MODQUEST-FSN

Wash-off, overflow compartment No. 4 B:

Combined akali treatment and oxidative desizing Recipe 2 Starting concentration: 4 g/l 0.5~1 g/l 25 g/l Concentration of feed liquor:

Na-persulfate ALTRANOL-CD / MODSCOUR-LF NaOH flakes 4 times


C:

Steaming 2 times 15 min/102ยบC U-Box-Steamer

D:

Recipe 3 3 Compartments at 80-95ยบC overflow rinse 1 Compartment cold overflow rinse

E:

Peroxide bleaching Recipe 4 Starting concentration 8 g/l MODSCOUR-BL 20 g/l NaOH flakes 40 g/l H2O2 50% 0.3 g/l MgCl2.6H2O (necessary if water hardness is below 8ยบGh or 10ยบEh) Concentration of feed liquor : 4 times

F:

Steaming 15 min/102ยบC U-Box-steamer

G:

Recipe 5 4 Compartments hot rinse overflow (counter current if possible)

H:

Cylinder-dryer


Fabric

Singeing extinguish

fabric

4 x wash-off impregnation bath U-Box-Steamer 50-60 sec. total 4 times conc. of 2 times 15 min/102ºC feed liquor

4 x wash-off 50-60 sec. total

fabric

Na2S2O8 NaOH

Modscour-BL ④ H2O2 fabric NaOH Impregnation bath, 4 times conc. of U-Box-Steamer feed liquor 15 min/102ºC

4 x wash-off 50-60 sec. total

cylinder dryer

See recipe 1-5

Continuous-pretreatment- plant


BLEACHING BY PAD-STEAM METHOD METHOD

:

MACHINE

:

STEAM TEMPERATURE STEAMING TIME SPEED MATERIAL :

: 102ºC : 25 min. : 100 m/min. 100% Cotton (household linen 120 g/m2)

RECIPE ❍ DESIZING

: :

❍ WASHING ❍ BLEACHING

: :

❍ ❍ ❍

Singeing Desizing (Enzymatic) Hydrogen Peroxide treatment(Pad steam)

KÜSTERS Combi-Steamer (with Flexnip “System)

Enzyme As per recommendation Allendet-NI/Altranol-OL 2 g/l pH As per recommendation Retention time As per recommendation 90ºC, 95ºC, 95 (3 Compartments) - Pick-up 100% - Water hardness 15º (french hardness) (=8º German hardness) That means magnesium chloride is not necessary. - Steaming time 25 min. at 102ºC

Recipes

❍ ❍ ❍ ❍ ❍ ❍

30 ml/l 70 ml/l 8 g/l 6 g/l 4 g/l 1 g/l

COMPETITORS NaOH 36 Bè H2O2 35% (= 46 ml/l H2O2 50%) Stabilizer Wetting agent Sequestering agent Defoamer


MODHERA CHEMICALS PVT. LTD.

❍ ❍ ❍

50 m//l 50 ml/l 10 g/l

NaOH 36Bè H2O2 35% MODSCOUR-BL

WASHING

95ºC, 90ºC, 60ºC, 50ºC (4 Compartments)

RESULTS

S

Grey Fabric

DP (STN 2.075/84) 1883

Competitor

1879

MCPL recipe

1917

S= Damage factor

Degree of whiteness

Water absorbency

35

/

0

71.1

Spontaneous

0

71.2

Spontaneous


Bleaching by pad steam method Method

:

Machine Steam temp. Steaming time Speed Material

:

:

Desizing (enzymatic) – Pad roll, combined alkali / Hydrogen peroxide treatment – Pad steam Babcock combi steamer : 100ºC : 15 minutes : 50 m/min. 100% cotton, plain weave, 216 g/m

Recipe (starting concentration) H2O2 50% 40.0 ml/l NaOH 50% 16.0 ml/l (24.5 g/l) MODSCOUR-BL 10.0 g/l Water : 8º German hardness=10º English hardness. If only deionized water is available add 0.3 g/l MgCl2.6H2O. Calculation of feed liquor concentration F1 F2 d2

Result Desizing

= = =

=

-

Water absorbency

-

Whiteness Seed removal DP decrease Damage factor

=

=

65% (Entry machine) 95% (Exit mangle) 30% 95 95 95-65 = 95-65

=

3.2 factor

very good (assessment by TEGEWA Violet = standard: note 9) = Penetration 3 sec. Spreading: Warp 35 mm Weft 31 mm good = complete = 6% very good, undamaged (Damage factor Eisenhut: 0.04)


Degree of polymerisation: In continental Europe fluidity is not normally used as an expression of chemical damage but a measure of the degree of polymerization (DP). It is obtained from the viscosity using a modified Staudinger equation. The development of these equations and their use is given by O. Deschler (textile-Praxis 1958, 13, p 927) Typical values for DP are: ---------------------------------------------------------------------------------------------------------Fibre DP ---------------------------------------------------------------------------------------------------------Natural fibres; cotton, flax, ramine 2300-3000 Acceptably bleached cotton 1800-2000 Regenerated cellulose polynosic 1000-1200 Viscose 250- 400 The relationship between DP and fluidity (F) for cotton is given by the equation: DP = 2032 [log10 74.35 + F ] F And this is shown graphically on page

-

573

Damage factor: The damage factor (S), suggested by O. Eisenhut (Melliand Textilber. 1941,22, p 424) relates damage to the change in DP and so takes into account high initial DPs. S=log10 (2000 _ 2000 + 1) log102 Ptx Ptx Pt = DP before chemical treatment Ptx = DP after chemical treatment 2000 = reference value The damage factor has been categorized to indicate the degree of damage. ---------------------------------------------------------------------------------------------------------8 factor comment ---------------------------------------------------------------------------------------------------------0.01 – 0.2 very good – undamaged 0.21 – 0.3 good – very carefully bleached 0.31 – 0.5 satisfactory 0.5 – 0.75 slightly damaged 0.75 badly damaged ----------------------------------------------------------------------------------------------------------


PEROXIDE BLEACHING - DISCONTINUOUS Package Yarn (Hanks) Jigger Liquor ratio 1:8 - 1:10 1:15 1:3 – 1:6 Temperature 98 98 Duration (min) 30-45 60 60 Magnesium chloride (g/l) ⇒ water 0.2-0.3 0.2-0.3 0.2-0.3 hardness 8-12° dH MODSCOUR-BL (g/l) 0.8-1.5 0.8-1.2 3-5 ALTRANOL-CD 0.5 ------Caustic soda flakes (g/l) 1.5-3 1.5-2 4-5 Hydrogen peroxide 35 weight-% (ml/l) 4-8 4-6 10-15

Jet 1:8 - 1:10 98 30-45 0.2-0.3

Winch 1:20 98 30-45 0.2-0.3

1.2-1.5 ---1.5-3 6-8

0.4-0.8 ---1-1.5 2-4

PEROXIDE BLEACHING : COLD PAD-BATCH Pick-up 100% Dwell time (h) 16-24 Magnesium chloride (g/l)⇒ water hardness 8-12° dh 0.2-0.3 MODSCOUR-BL (g/l) 4-6 Caustic soda flakes (g/l) 15-20 Hydrogen peroxide 35 weight-% (ml/l) 40-60 PEROXIDE BLEACHING : PAD STEAM Combination U-Box Steam temperature (°C) 100 97-99 Dwell time (min.) 7-20 20-50 Magnesium chloride (g/l)⇒ water 0.2-0.3 0.2-0.3 hardness 8-12° dH MODSCOUR-BL (g/l) 4-8 8-10 Caustic soda flakes (g/l) 20 20 Hydrogen peroxide 35 weight-% (ml/l) 60-40 40 Pick-up : 100%

Pad-Roll 85-90 60-120 0.2-0.3 8-10 20 40

The above technical presentation proves MODSCOUR-BL as ECONOMICALLY & ECOLOGICALLY improved peroxide bleach


Modscour-BL