problem solving - knits

7/22/2019 Problem Solving - Knits

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Problems faced during wetProblems faced during wetProblems faced during wetProblems faced during wetProblems faced during wet

processing of Cotton Knitweaprocessing of Cotton Knitweaprocessing of Cotton Knitweaprocessing of Cotton Knitweaprocessing of Cotton Knitwearrrrr:::::

Probable causes andProbable causes andProbable causes andProbable causes andProbable causes and

remedial measuresremedial measuresremedial measuresremedial measuresremedial measures

- Mr. A. K. Prasad

- Mr. S. Pitchai

- Mr. J. B. Pawar

Clariant India Ltd.


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l Adjust the jet pressure, calculateweight of the fabric to be loadedbased on the rope length,diameterof the tube & gsm.

l Always load the fabric at warmafter adding Sandoclean PCJ/LFD/HPJ Liq. For foams due toimpurities (lubricants, wax),antifoam based on non-siliconechemicals are recommended,AntimussolHT2S Liq.

l Check the filter and clean beforedyeing and pretreatment.

l Use Elfugin KNIT as lubricat-

ing agent while knitting.l Oxidised oil marks are removed

by special scouring with 1.0-2.0%Sandoclean PC/PCJ Liq.,0.75 - 1.5% ImerolSR Liq. Boil,30 min. at pH 9.0 followed by

rinsing after neutralising.

l Lab pre-trials are requiredbefore proceeding to bulk to findout optimum dosage quantity.

l Store & transport the fabric hori-zontally, in suitable plastic or cloth

bags.

1. Entanglement of fabrics

2. Oil marks on fabrics

3. End-marks

l Very less jet-pressure, over loading offabrics, causing fabric tube to Jam in frontof the machine, making it difficult for thewinch to lift and transport the fabric.

l Too high jet pressure also leads toentanglement at the reel and accumulationof fabric at the rear side of the machine.

l Foaming due to the presence of lubricantsused for knitting or due to surfacants /wetting agents that has more foamingproperties.

l If the fabric is stored for more than a week,

it may oxidise depending on the quality ofknitting oil or lubricant used.

The quantity of such oil/lubricant on thefabric can be more because of splashingof oil due to unexpected machineryproblems or due to irregularity of yarn.

l Improper house keeping and handlingof rolls.

l If fabric rolls are stored on their ends, knit-

ted fabrics are prone to get End Marks.

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The main endeavour of any business enterprise is to produce acceptable quality product at minimum cost.With the advent of new dyeing machines, advanced speciality chemicals and application of managementtechnology, producing QUALITY FABRICS is possible by appropriate utilisation of technology & process control rightfrom knitting to finishing.

As far as processing is concerned, processing of tubular fabric is being done in softflow machines more andmore even though processing in winches is also still being continued. Since knit goods are predominantly dyedusing REACTIVE dyestuffs, problems related to reactive dyeing only are discussed.

In overflows jets, there are four factors that should be adjusted when setting up a machine for process. These are

1. WATER LEVEL

2. WINCH SPEED

3. JET PRESSURE

4. NOZZLE SETTING (Depending on the machine)

All these factors will influence the running of the machine & affect the quality of fabric dyed, even thoughappropriate chemicals & dyestuffs are used.

The following are some of the common problems faced during the wet processing of knit goods, its causes andremedial measures.

PRE-TREATMENT

Problems Probable Causes Remedial Measures


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l Check the presence of any sharpobject in the machine.

l Provide magnetic filters in water/steam lines. Use Sirrix 2UDI inpretreatment, to ionise Fe ionspresent in grey cotton and keepin complexed form after theirremoval.

l Clean main water tanks / pipes.

l To follow the following process forpretreatmentSirrixYK Liq. 2.5% 60CSandocleanLFD/PCJ Liq. 0.5% 20 min

Rinse Warm, 60C, 10 min

Sandoclean LFD Liq. 0.25%Stabilizer SIFAM Liq. 0.25% Boil

NaoH Flakes 1.0% 30 min

H2O

22.0-3.0%

Hot wash 80C. 15 Min.

Neutralise with SirrixN Liq.0.5%, 60C, 20 min

l Fabric may be singed to removethe protruding fibres.

l To reduce the hydromechanical

action on the fabric, machine canbe run at a compromising speedduring scouring & washing. (i.e.running at optimum speeddepending on machine type)

l Use of Lubricants like ImacolCGLiq.

l Clariants BIO-BLEACH conceptgives best results without toomuch fluff.

Process:Sandoclean PCJ Liq. 0.5g/l

Sirrix 2UDI Liq. 2.0g/l60C,

Imacol CG Liq. 0.3g/l10 min

Then add

BactosolCA Liq 0.6-1% } 60C, 45minAfter this process, continue scour-ing in the same bath.

l By cutting a vertical slit of 10-15cmnear the joint of two tubes enablesthe air to escape.

l The use of larger diameter nozzlewill also minimize the problem.

l Addition of deaerating & penetrat-ing agent (SandozinNA Liq.) canbe added as a safety measure.


l Presence of sharp metallic parts in someparts of the machine.

l Presence of metallic particles in peroxidebath.

l Presence of heavy metal ions(Fe, Cu) in the fabric/Water/Caustic Soda.

l Bad condition of water tanks / pipes.

l Presence of heavy concentration of Fe ionscarried over from the residual caustic sodaafter mercerising.

l This problem mainly occurs when the grey

cotton quality is poor.Other possible causes are :-

l Too high mechanical stress on the fabric

results in pilling or metal to fabric andfabric to fabric frictions.

l Too much fluff formation on the fabric,because of bad running properties created,action of alkali & low cost solvent basedwetting agents.

l Long duration of running due toreprocessing

l If the pieces are densely sewn & thestructure of knit pattern is tight, theentrapped air cannot go out & resultsin balooning which in turn leads to

entanglement.

4. Pin-hole damage

5. Uneven surface appearanceparticularly on interlockfabric

6. Balooning of tubular knitsof heavy texture fabrics

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l Presence of Ca & Mg salts on fabric and inwater leading to precipitation in alkali and

redeposition thereof.

l Due to the use of poor quality of wettingagents which have low alkali stability, andhence cannot assist the penetration of

Caustic Soda for efficient saponificationreaction. Because of poor detergency anddispersing effects, paraffin wax cannot beremoved completely.

l Redeposition of Oil / Wax.

l The presence of iron on the fabric acts asa decomposition catalyst for H

2O

2. In a

freely circulating bath new sources of ironoxides form, as a chain reaction ofhomolytic cleavage of H

2O

2into hydroxide

radicals which attacks cellulose to formoxycellulose.

l Due to improper washing off after pretreat-ment, residual peroxide will be left over onthe fabric. If it is not removed completely, Itmay lead to the decomposition of somesensitive reactive dyes to non-homoge-

neous components, in a mixed shadedyeing.

l Localised swelling of unmercerised cotton.

l Drying up of improperly neutralised alkaliafter mercerising.

l Damage of cellulose during the fasttransport through the jet nozzle. Thedamaged portion of the substrate is deeplydyed. (mainly on viscose)

l Protonic pretreatment beforescouring gives an outstanding

cleaning effect.Light weight fabrics:

Sirrix2UDI Liq. 1-2g/l

SandocleanPCJ Liq.0.5g/l

60C, 30 min, Rinse

Heavy weight fabrics:

SirrixYK Liq 2.0g/l

SandocleanLFD Liq. 0.5g/l

80C, 30 min, Rinse hot

Use of SandocleanPCJ Liq. isrecommended as a wetting agent.The synergistic properties of the

product helps to penetrate into thecore of the fibre by eliminatingfibre-liquid surface tension, andsaponification of all impurities.So, fabrics obtain very goodabsorbancy.

l Ensure high temp. rinsing at 80C.

l Addition of Sirrix 2UDI Liq. inPeroxide bleach bath or by onestep combined protonic pretreat-ment & scouring.

SandocleanPCJ Liq. 0.5g/l 60C,

Sirrix 2UDI Liq. 1g/l 20min

Then continue peroxide bleachin the same bath. Addition ofStabilizer SIFAM Liq. alsoprevents the formation of atomicoxygen responsible for cellulosedamage.

l To add BactosolARLI Liq. in theneutralisation bath for eliminatingH

2O

2in a biological way.

BactosolAPN Liq. can be usedin winch.

l Both the products promote quickly,under optimum conditions, theredox conversion of H

2O

2to

water & oxygen.

l Ensure careful feeding of alkali (bylinear dosing)

l Efficient neutralisation of the alkaliusing 0.5-1.0% SirrixN / YK Liq.before dyeing.

l Loading the fabric after setting thebath with Imacol C2G Liq.alongwith SandocleanPCJLiq.ensuring proper piling & smoothrunning.

7. Poor absorbancy offabrics after scouring /

Peroxide boil

8. Tendering of fabric duringbleaching

9. Lower dye-yield & tonechanges in some dyed lots

10. Dark coloured patches &Creases

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l Presence of insoluble earth alkali on somesubstrate qualities, over stabilises H

2O

2

making the bleaching ineffective.

l Improper choice of mercerising wettingagent.

l Because of poor stabilization of H2O

2

bleaching

l Improper pretreatment & use of poorquality wetting agents which could notremove the mineral oil-content from thefabric completely.

11. Whiteness variation

12. Uneven wetting duringmercerising

13. Inconsistency in basicwhiteness after pretreatment

14. Light coloured reservedportion on Cotton / Lycrafabrics

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l To achieve the optimum consump-tion of H

2O

2a protonic pretreat-

ment with Sirrix

2UDI Liq. beforebleaching is recommended.

l Use 2.5 - 5.0 gpl Mercerol QWspl Liq. / MercerolRWLF Liq.

l Use Stabiliser SIFAM Liq., forcontrolled decomposition of H

2O

2.

l After a protonic treatment fabricshould be heat set & bleachedusing Sandoclean PCJ Liq. asscouring & wetting agent, atpH 10.5.


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l Some grey cotton carry a lot of hardnessforming substances, which interfere in thebleaching reaction of Hydrogen Peroxideon cellulose.

l Overdosing of optical whiteners & dryingat temperature above 140C.

l Improper choice of optical whitener.

l BHT (Butylated Hydroxy Toluene) ispresent in polyethylene bags as an anti-oxidant. If the fabric is in the neutral oralkaline side the yellowing reaction starts.

l Use of optical whitener which has poorstability in acidic medium.

l If Acetic Acid is used for reducing the pHat the end of finishing operation, it forms a

buffer of sodium acetate at the liquid-fabric interface and prevents the entry offurther Acetic acid to the core of the fibre.

l Improper selection of optical brighteningagent.

l Poor washing off.

l Local drying up marks because of more timegap between hydroextraction and drying.

l The basic whiteness of fabric is very low.

l Improper selection of optical brighteningagent.

l Give a protonic pretreatmentbefore Hydrogen Peroxide bleachusing

Sirrix2UDI / YK Liq.

SandocleanPCJ Liq.

l Use optimum quantity of opticalwhitener & controlled drying,preferably below 130C. Use acidstable OBA in case of neutralisinglike LeucophorBMF Liq.

l Use LeucophorBA/BH Liq. asoptical whitening agent in exhaustapplication.

l Finish the fabric in slightly acidicmedium (pH 5.5 - 6.0) usingSirrix 2UDI Liq., and keep thefabric away from Nitrogen oxides.Use wrapping without BHT.

l Use LeucophorBMF which isstable under acidic pH of finishbath.

l Use SirrixN for reducing the pHof finish bath which can penetrate

into the fibre to neutralise the corealkali, which is responsible for

alkaline pH.

l Use LeucophorBFBI/BMF Liq.as optical brightening agents whenapplied by padding technique.

l Wash at 85 C to c ompletelyremove all impurities & neutraliseusing SirrixN Liq.

l Dry the hydroextracted fabrics asearly as possible.

l Natural whiteness of lycra can beimproved by giving a reductivescour before bleaching.1.5 g/l SandocleanPCJ Liq.2 g/l Soda Ash

3 g/l Sodium HydrosulphiteHeat to 75-80C & run 60 min.Cool the bath to 60C & drop bathRun 15 min in a fresh bath con-taining 0.3 ml/l H

2O

2(50%), Rinse

cold.

l The selection of optical brighten-ing agent must suit both the lycra

& the hard fibre in the fabric.Apply Leucophor BMF Liq.0.8% in a reducing bath (SoduimHydrosulphite) at pH of about 5.5.

1. Poor whiteness

2. Poor wash fastness ofwhites

3. Yellowing of whites afterstorage

4. Yellowing of whites if finishedat acidic side as per Okotexrequirement

5. Aqueous extract of the fabricis alkaline

6. Tailing of white fabrics, whenOBA is applied by paddingapplication

7. Yellow streaks on whitefabrics

8. Poor whiteness on Cotton / elastane (lycra) fabrics

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OPTICAL BRIGHTENING


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l Poor working practice and poor storageconditions.

l Improper choice of finishing agent.

l Improper processing methods.

9. Loss of whiteness retentionof cotton / elastane fabrics

10. Drop of whiteness value afterfinishing

11. Loss of elastic properties incotton / elastane fibres

l The following should be avoided:-Unsatisfactory optical whitener.Use only Leucophor BMF/BHLiq.

-Drying with air heated by com-bustion gas or oil

-Unsatisfactory softener, useSandolube HD Liq. an dCerapermMW Liq.

- Do not store white goods in ex-cessive light (natural / artificial).

-Exposure to excessive burnt gasfumes (nitrogen oxides)

-Lack of air tight & inert packing.

-Packing which releases phenolicderivatives.

l Use appropriate finishingchemicals.

i) WINCH

CeranineHINI Liq. - Nonionic

or

CeranineAS Liq. - Anionic

or

CeranineRSFLF Liq. - Amphoteric

ii) SOFTFLOW

CerampermHIS Liq. /SandolubeHD Liq. - Exhaust

CeraperamMW / UP Liq. - Padding

iii) TOWELS

DilasoftRWS Liq.

CerapermHIS Liq.

CerapermAQUA Liq.

l Avoid processing of such blendsin strongly acidic (pH10.5).

l Avoid use of Sodium Hypochloritel Excessive steam ageing of printed

fabrics. The temperature in cot-tage steamers should not exceed104C (0.2 Kg / cm2 steam pres-sure) during 30-60 min to main-tain the properties of elastanefibres.

l High tension and over heatingabove 150C should be avoidedin finishing.

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l Rope length of fabric is not uniform in alltubes of the machine.

l Worn out Teflon rolls on tubes of thewinches causes different reel speed affect-ing effective cycle turn over of the tubes.

l Varying GSM from rope to rope (HigherGSM fabric has lower rope length,compared to lower GSM fabric of sameweight)

l Check tightness factor.

l It can be due to rapid addition of dyesand chemicals, mainly alkali (Soda Ash /Caustic Soda).

l Improper dissolution of dyestuff by dissolv-ing with insufficient amount of water.

l Improper addition of Caustic Soda.

l Uneven pressure head in tubes. Whereverpressure is low, this could reduce speed inone rope.

l Stoppage or damage at stitches duringrunning.

l Improper pretreatment.

l To load fabrics with same ropelength in all the tubes.

l Replace the worn out Teflon rollwith a new one & avoid use ofsolvent containing low cost lubri-cants based on acrylamide. UseSandocleanPCJ Liq. as a wet-ting / scouring agent which isbased on linear fatty alcohol ofnatural origin & use ImacolC2GLiq. which forms active film overthe fabric keeping the fabric veryductile.

l Pretreat the fabrics usingClariants PROTOBLEACHconcept.

l Check that the dyestuff is dis-solved properly & dosed. Verifyrope speed and chamberloading conditions.

l Use Drimagen ER Liq. as perthe recommendation, which hasgood disaggregating effect duringdye dissolution, uniform distribu-tion during salting stage & pHregulation effect during alkali

addition.

l Ensure that any large undissolvedparticles do not enter into thedyeing m/c (Always the dissolveddyestuff should pass through afine stainless steel mesh strainer).

l Use Drigmagen ER Liq. whiledosing NaOH in dyebath.

l Increase the pump rate toincrease the pressure.

l Clariants PROTOBLEACH con-cept using

1. SandocleanPCJ Liq.

2. Sirrix2UDI Liq.

3. StabilizerSIFAM Liq.

3. NaOH

3. H2O

2

4. BactosolARLI Liq.

ensures perfectly neutral sub-

strate ready for dyeing with instantabsorbancy and no residualperoxide.

1. Uneven shade from ROPEto ROPE

2. Uneven dyeing in a rope

3. Dye spots

4. Uneven dyeing in one ropeonly

5. Shade variation

DYEING

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6. Reduction in dye yield

7. Batch to batch reproduction

8. Dimpling (or cockling) offabric surface

9. Pilling of fabrics

10. Fine creases & unlevelness

due to abrasion on cotton &polycotton blends

l Addition of Drimagen ER Liq.enables to dose mixed alkali veryeffectively for perfect & uniformdiffusion of dyestuff in to the coreof the fibre.

l Dyestuff should be dissolved inacidic medium.

l If the process water passesthrough actified carbon unit,chlorine should be removed.

l Check the liquor rate using Saltreading.

l Use Clariants PROTOBLEACHconcept using SirrixPK Liq. or

Bactosol

ARLI Liq. for clearingresidual H

2O

2.

l Use RevatolSpdr. 1 -2 g/l whiledyeing cotton / viscose usingDrimareneXN dyes.

l Standardise dyeing programmeusing identical special chemicals,as per the recommendations pref-erable using Drimarene CL/KLiq. for pale shades &

Drimarene XN for dark shadesas these dyestuffs are having leastsensitiveness to minor variationsin MLR, salt quantity, temperature& time.

l Increase the liquor ratio andarrive at a compromise speed.

l Use 0.5 - 1.0 g/l ImacolC2G Liq.in dye bath.

l The elastic recovery of cottonbeing low compared to syntheticfibres is the primary reason whya universal anticrease productcannot perform very well in everycase on every fibre. Only an effi-cient range of dyeing lubricantscan solve all the problems.

Imacol C / C2G Liq. - Cotton /Cellulosics

ImacolMPE Liq. - For micro polyester

Imacol PAM Liq. - For polyamide

microfibres

l Presence of chlorine content in water.

l Using bicarbonate containing hot water(pH above 9) for dyestuff dissolution.

l Varying material to liquor ratio.

l Presence of residual peroxide decomposessome sensitive reactive dyes, the effect of

which is very predominant in pastel shades.

l Reduction of Drimarene XN dyestuffcaused by the reducing atmospherecreated because of the reducingsubstances present in water (when dyeingtemperature is 85 - 95C).

l If the process - parameters, products &non- compatible dyestuffs are used thedye-fibre reaction will not attain same endpoint always.

l Running heat sensitive (or thermo plastic)fabrics at too low speed during cooling.

l Because of salt and alkali addition in thedyebath, the specific gravity of the bathincreases. Hence, even fabric surface tosurface contact at high speed generatespilling due to heavy friction.

l Many phenomena appear during the dye-ing of textile fabric in the JET dyeing m/caffect the surface of the textiles. They arei) Twisting of the ropeii) Pressure on the fold.iii) More weight on the fold which com-presses the fold if no lubrication is applied.iv) Tension on fibres.

v) Friction over fabric and also on machineparts with force.


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11. Back - staining of color fromthe dyed portion to adjacent

white or pale colored fabric

12. Streakiness

13. Tailing effect on critical shades(khakis, Greys, Olives &Browns)

14. Unlevel dyeing with lighterreserved portions

15. Poor rubbing fastness

16. Poor wash fastness

l This problem is visible after knitting thedyed yarn and when washing the fabric.

l Uneven absorption of dyestuff particularlywhen dyeing fabrics of light structure &

heavy gsm.

l Yarn parameter variation.

l It is due to poor migration of the dyestuff(on perfectly pretreated fabric with no

alkalinity & residual peroxide).

l Calcium & magnesium ions present inwater/ Salt increase the hardness of dye-bath and favours aggregation of dyemolecules and lead to greater risk of

unlevelness.The aggregated dye will tend to migratemore slowly than the single dye moleculesor smaller aggregates, so that levelling isnot very uniform at the time of alkalifixation.

l It mainly depends on the type of substrateand the finishing chemicals used.

l Improper fixation of dyestuff.

l Improper washing of hydrolysed dyestuff.

l After treat the dyed fabric using

SandopurRSK / SW / RSD Liq.

depending on the class of reac-tive dye used, followed by acationic fixative treatment.(Fastness should be ok in iron -test)

l Use Destofil YL Liq. as thesoftener.

l Use Thiotan AS Liq. on whiteyarn (cellulose/nylon) to preventtinting of colour.

l Use Imacol C2G Liq. in thedyebath, and DrimareneXN Liq.

is the recommended dyestuff, forhigh degree of levelness.

l Check unevenness in yarn.

l Use Drimarene XN Liq. bymigration technique with the aidof 0.5 g/l DrimagenER Liq.

l Use Sandopur R3CZP Liq. for

conditioning the dyebath &sequestering calcium & magne-sium not unaffecting the final

shade. Dyeing process can befurther improved by using.

DrimareneCL / K Liq. - Forpale shades

Drimarene XN Liq. - For deepshades

l Addition of Sandopur R3CZPLiq. also facilitates easy removalof dye hydroxylates duringwashing off operations.

l Do protonic pretreatment beforescouring / bleaching.

l Use OptifixF Liq. for removingtraces of hydrolysed dyestuff.

l Finish the goods usingSandolubeJNF Liq.

l Use high performance reactivedyes Drimarene CL / XN Liq.with sufficient quantity of alkali.

l Soaping should be carried outusing SandopurRSK / SW Liq.which can dissolve hydrolyseddyestuff and keep them in thewash bath, preventing theirredeposition on the substrate.


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l Improper selection of reactive dyestuff,without considering exhaustion, reactivity

and substantivity of the dyestuffs.l A reactive color could be highly exhaus-

tive but if its reactivity is medium or lower,fixation will be poor and a hydrolyseddyestuffs should be washed off. Otherwise,unwashed dyestuff appears as patches. Inother words, if a color is highly reactive butlow exhaustion, this would result in thecolour reacting with the fabric even whilein the process of adsorption and, at mostfavourable sites (amorphous regions) thecolor will strike and cause patchy dyeings.

l Use Drimarene CL Liq. whichare medium substative and

Sandopur

RSK / SW Liq. forwashing off unfixed dyestuff.

22. Uneven and patchydyeing


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l Improper feeding and batching of fabric.

l Improper pretreatment

l Cotton quality

l Immature cotton % is more.

l Using high density oil.

l Poor rheological property of print paste.

l Thickening of paste due to electrolytes onfabric.

l Due to high concentration of binders usedin oil system.

l High HCHO fixer.

l PCP is also present on grey cotton.

l

Due to high solid Binders used in pigmentprinting.

l Improper choice of Binder & Fixer.

l Improper Choice of Binder.

l Improper working method

l Proper batching using suitable ex-pander in batching m/c (Recom-mended the preparatory depart-ment to use ImacolC2G Liq. inthe process).

l Fabric should be pretreated thor-oughly, as per the followingmethod.SandocleanLFD Liq. - 0.5%Sirrix2UDI Liq. - 1.0%NaOH flakes - 2.5%StabilizerSIFS Liq. - 0.4%H

2O

2- 2-4%

followed by hot wash at 80C &Neutralising.

l Use ElfuginKnit-1% in the printpaste.

l Use low density MTO with 0.784specific gravity or usedeodorised Kerosene.

l Use Clariants Printofix package(Aqueous system) with Binder2000, Printogen RM Liq. &Thickner CN Liq. as the keyproducts.

l Use 3 gms/kg of PrintogenRMLiq. in the print paste.

l Ensure proper removal of allelectrolytes

l Use aqueous system of Clariant(Printofix concept)

l Use low HCHO fixer (PrintofixFixativeWAF Liq.)

l

Use Printofix Modifier

99 Liq.

l Us e Binder 2000 Liq. &Printofix Modifier 99 Liq. toimprove dry rub fastness.

l Use Printofix FixativeWAF Liq.for improving wet rub fastness

l Use Binder2000 Liq., PrintofixFixativeWAF Liq.

l Check the curing temperature andamount of Binder 2000 Liq.

corresponding to the pigmentquality.

1. Creases / Folds

2. Dark & Light prints inPigment printing

3. Haziness in pigment printing(mainly on blotch designs)on low gsm fabrics

4. Oil odour

5. Smudging of OUTLINES

6. Presence of HCHO & PCPbeyond the limit values forexport

7. Harsh feel

8. Poor Wet & Dry Rub fastnesseven after proper curing

9. Dulling of prints after washing

10. Poor fastness of Prints

PRINTING


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11. Thickener consumption ishigh

12. Flushing Problems

13. Crackling khadi on interlockquality fabric

14. Harsh feel due to unevenremoval of gum on reactiveprinted goods

15. Tinting on white ground fromthe adjacent Turq. Blue orBrilliant Blue coloured portion(reactive print)

16. Poor wash off in polyesterprints (with disperse)

17. Harsh feel on reactive printedfabrics

l Thickener is not stirred before use.

l Water used for preparing the paste is hard.

l Electrolyte impurities coming from water& fabric.

l Improper choice of Khadi.

l Poor quality of Thickener.

l Poor quality of Soap.

l Improper choice of Thickener & dyestuffwith poor solubility.

l Low quality of AGBV gum.

l Poor conditioning of Silicate bath & forma-tion of precipitations / silicic acid.

l Use high speed stirrer beforeusing the paste.

l Use soft water & if required addSirrix 2UDI Liq. to adjust thehardness.

l Use soft water & print on protonicbleached fabric using PrintofixConcept.

l Use PrintofixLack Mpaste on

interlock fabric.

l Use 5 g/l Ekaline FI Liq. &5 g/l Sandopur RSKI Liq. inwashing.

l Use Drimarene Blue CLBR,Drimarene Turq. CLB &Synthetic Thickener.

l Pad and dry with

ThiotanAS Liq. - 20 -30 g/l

Urea - 20 g/l

Sod bicarbonate - 10 g/l

before printing.(Pad-Dry-Print).

l Use PrintofixThickener LSpdr.

l Use SandopurPC Liq. in wash-ing off (5g/l).

l Use SirrixSAI Liq.Conc. -5 g/lin silicate padding bath.

l Use SandopurRSKI Liq. -5 g/lin soaping (without neutralisingwith acetic acid before soaping).

AREAS OTHER THAN PIGMENT PRINTING


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l Because of various processing operations,brittleness on the fabric is developed, whichdoes not allow the needle to penetrate the

single knit structure smoothly, but pierces,damaging the knit structure.

l At pH 5.0 to 5.5 most of the cationic soft-eners exhaust onto cellulose fibres, inde-pendent of temperature. An exception tothis rule is the softening of dyed cellulosicmaterial which has been treated withcationic fixatives.

l The fibre has a cationic charge due to fixa-tive. In an acid bath, cationic charge on the

fibre and that of softener are activated andrepel each other.

l Using softeners which have poor shearforce stability, which forms spots after theemulsion system is disturbed.

l Many of the commercial aminosiliconeshave particle size above 0.1 Micron which

cannot penetrate into the core of the fibreto provide an excellent product distributionto give inner softness without lookinggreasy.

l Due to poor capacity of the softener todevelop gliding behaviour on the surface.

l Improper softener selection.

l Improper softener selection. Cotton fibre ishydrophilic. It becomes hydrophobicbecause of the oriented adsorption ofcationic softener.

l If softener is applied by exhaust method, itis difficult to exhaust the softener since onlynon-ionic softeners / anionic / amphotericare recommended for white goods.

l Use of SandolubeJNF Liq. (fordyed) and Sandolube HD Liq.(for white) material.

l Under such conditions satisfac-tory exhaustion of the softner canbe achieved using

SandolubeJNF Liq.

and / or

SandosoftSPK Liq.

at pH 7.0

l Softener & dyefixative can bestripped, before redyeing, using

1.0 g/l LyocolRDNI Liq.

2.0 g/l Acetic Acid at 80C, 30 min,Rinse & Neutralise.

-Use of SandolubeJNF Liq. (Jetstable & non foaming) in finishing.

l Use Sandoperm MEJ Liq. byexhaust method or Ceraperm

MW Liq. by padding method. (forwhites & dyed fabrics)

l Both the above products increasetechnological properties (mainlysupports elasticity), apart fromincreasing the softness

l Use Ceraperm JET Liq. byexhaust method. Or Ceraperm

MN / UP Liq. by paddingapplication.

l Use CeranineRSFLF Liq.

l Use Dilasot RWS Liq. &Sandolube HD Liq. in exhaustand Sandolube HD Liq. inpadding.

l Use Ceranine RSFLF Liq. atpH-5.0. Use acid stable OBA likeLeucophorBMF Liq.

l Pad with Ceraperm MW Liq. &CerapermMN orUP Liq.

1. Sewability damage

2. Poor handle of the fabric aftercationic dye-fixing &finishing treatment

3. Dark spots on the fabric

4. Poor inner softness &elasticity of fabrics

(Dyed goods)

5. Very poor handle in thickpique & air-tex fabrics(Dyed goods)

6. Limpy feel of rib fabrics

7. Poor hydrophil icity of fabrics

8. Poor feel on white fabrics

FINISHING


17/17


l Use Sandotor HV Liq. Thehydrophilic projecting polyether

groups on the surface of treatedfabrics enables easy penetrationof liquid through the capillaries. Or,us e Cassapret SRHA Liq.with CerapermMW Liq. conc.

l Finish fabrics with Sandolube

products which reduce the frictionbetween the textile and thecutting blades.

l BactosolCA Liq.Conc.

treatment.

l Use Sandoperm MEJ Liq. orCeraperm JET Liq., which arejet-stable silicones.

l Check for any sharp objects.

l Clean frames at regular intervals.

l Core alkali should be removed

using Sirrix N Liq. or Sirrix2UDI Liq. & Acetic acid mixture50:50.

l The fabric to be finished shouldnot have anionic residues, siliconecan be added to hot bath at 50Cbut never heat after addingsoftener.

l Use Stripper SS for removingsilicone stains.

l Navy shades can be produced

using Drimarene

XN Liq. insteadof vinyl sulphone dyes.

l Efficient removal of core alkaliusing Sirrix2UDI Liq.

l Use the following recipe

NuvaHPC Liq. 60 g/l

NuvaFW Liq. 10 g/l

CerolPA Liq. 40 g/l

Pad at 70% PU

Dry & cure at 180C 1 min.

l Functional knitted articles are manufac-tured having synthetic fabric inside & cellu-

losic fibre outside (sportswear).

l During cutting, a no. of layers of fabric arecut using knife blades, which gets heateddue to large friction involved developing atemperature of about 300C. Hence, itcauses melting of synthetic fibres leadingto sticking at edges.

l Poor quality of cotton.

l Often encountered when the goods aregiven silicone finishing agent treatment insoftflow machine using SILICONES whichare NOT jet stable.

l Presence of embedded metal object in thefinishing line.

l Oil drips from a frame, usually on oilysoftener.

l Residual caustic left in viscose & its blends

after reactive dyeing can degrade theviscose when heated.

l Due to direct heating of the bath / silicone.

l Maintenance of pH not only in the bath butalso on the fabric is important, otherwiserubbery film formed in finish bath willadhere to the fabric & forms silicone stains,which appears after drying.

l The effect is low because of the structureof the fabric.

9. Poor hydrophilicity onpolyester on two sided fabrics

with one side cotton & otherside polyester

10. Sticking at ends while cuttinggarments made of cotton &polyester (Two sided fabrics)

11. Dead cotton on dyed fabric

12. Dark coloured oil spots

13. Pin hole seen in a straight lineat regular repeat intervals

14. Drip spots in a straight line

15. Damage of viscose fabrics

after dyeing

16. Silicone stains on fabrics evenafter using Jet stable silicone

17. Oil stains near the edge oftubes & also on the body

randomly (Mainly on Navy& Black Shades

18. Poor water / oil repellant finishon Air tex fabrics

Many of their dyestuff, pigments and chemicals are patented by CLARIANT LTd. in numerous industrial countries. Registered trade mark of CLARIANT LTD., MUTTENZ, Switzerland and CLARIANT INDIA LTD. are the licensed users of these trade marks.Trademark licensed to CLARIANT LTD. in numerous countries. The signs and appear only at the first mention of the product.The information and recommendations presented here were compiled with the utmost care, but cannot be extended to cover every possible case.They are intended to serve as non-binding guidelines and must be adapted to the prevailing conditions.

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