Finishing

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Finishing

  1. 1. TEXTILEFINISHING
  2. 2. INTRODUCTION Dyeing and printing is not the ultimate steps Something is required to make the fabric moresuitable for end-use Quality of the fabric in terms ofappearance, handle, functionally enhanced bysome physical means or by chemicals Therefore, ultimate value addition is done to thefabric by finishing
  3. 3. WHAT IS FINISHING ?????? Finishing is a final process given to a textile materialto Give a good appearance Desirable feel Impart certain durable propertiesStiffnessSoftnessWash and wear finishWater repelling finishFire proof finish etc. To impart some desired functionalproperties
  4. 4. CLASSIFICATION OF FINISHING Classification according to the nature of finishAccording to the nature of FinishPhysical or Mechanical Finish1) Calendering2) Sanforizing etc.Chemical Finish1) Mercerization2) Easy care finish etc.
  5. 5.  Physical or Mechanical Finish Mechanical / Physical finishes involve specific physicaltreatment to a fabric surface to cause a change in thefabric appearance Also known as dry finish Compacting (Shrinkproofing) Calendaring Raising (Napping, Sueding) Shearing Polishing Corduroy Cutting Decating Chemical Finish Chemicals are used followed by curing or drying Also known as wet finish
  6. 6. CLASSIFICATION OF FINISHING Classification according to degree of permanenceAccording to degree of permanencePermanentFinishTemporaryFinishDurable FinishSemi - DurableFinish
  7. 7. DEFINITIONS Permanent Finish: Usually involve a chemical change in fibrestructure and do not change or alter through out the life of thefabric Durable finish: Usually last through the life of the article, buteffectiveness becomes diminished after each cleaning; and nearthe end of the normal use life of the article, the finish is nearlyremoved Semi-durable finish: Last through several laundering ordrycleanings and many are renewable in home laundering ordrycleaning Temporary finish: Are removed or substantially diminished thefirst time the article is laundered or drycleaned
  8. 8. CLASSIFICATION OF FINISHING Classification according to performanceAccording to PerformanceAesthetic Finish– Improved /Altered Appearance1. Calendering2. Fulling3. Mercerization4. Napping and sueding5. Plisse6. ShearingFunctional Finish– Improved /Altered Performance1. Antiseptic2. Antistatic3. Crease resistant4. Durable press5. Flame resistant6. Mothproofed7. Shrinkage control8. Soil release9. Water and stain repellent10. Waterproof
  9. 9.  Aesthetic Finish These finishes modify the appearance and / or handor drape of fabrics Functional Finish These finishes improve the performance propertiesof fabrics
  10. 10. AESTHETIC FINISHES Aesthetic Finishes modify the appearance and/or hand or drape of the fabrics. Fulling Mercerization Napping And Sueding Plisse Shearing Softening Stiffening
  11. 11. FUNCTIONAL FINISHES Functional Finishes improve the performanceproperties of the fabric ; like durability,strength etc. Antimicrobial/Antiseptic Antistatic Crease resistant Durable Press Flame Resistant Mothproof Shrinkage Control Soil Release Water Proof/Repellant
  12. 12. WOOL FINISHING ROOT
  13. 13. COTTON FINISHING ROUTE
  14. 14. SILK FINISHING ROOT
  15. 15. SYNTHETIC FIBRE FINISHING ROOT
  16. 16. COMPACTING - SHRINKPROOFING
  17. 17. COMPACTING - SHRINKPROOFING Controlled residual shrinkage is an importantquality parameter for manyfabrics. Forexample, excessive shrinkage is undesirable forfabrics to be made intogarments. Here, the residual shrinkage should be less than2% otherwise the garment will not fit after it islaundered.
  18. 18. WHY FABRICS SHRINK ??? Crimp Thickness of yarn Stretching Tension.
  19. 19. SANFORIZER Mechanical compacting is one method of reducing residualshrinkage. The process forces yarns closer together andthe fabric becomes thicker and heavier. As a result ofthis, the net yardage yield is reduced. A Sanforizer is a fabric compactor developed by CluettPeabody. The term Sanforized, is their registeredtrademark and is used to market fabrics that meetcertain shrinkage specifications. The term Sanforized isnow generally accepted to mean a fabric that has lowresidual shrinkage and the term Sanforizing is used todescribe shrinkproofing processes. The process, consists of arange where the fabric is firstmoistened with steam, to make it more pliable, run througha short tenter frame (pup tenter) to straighten andsmooth out wrinkles,through the compressive shrinkagehead and then through a Palmer drying unit to set thefabric.
  20. 20. FABRIC SAMPLE
  21. 21. SANFORIZING RANGE
  22. 22. COMPACTOR HEAD The key to any compactor is the head where force isapplied to move parallel yarns closer together. Morefabric must be fed in than is taken off. A Sanforizer uses a thick rubber blanket runningagainst a steam heated cylinder as the compactingforce. The thick rubber blanket first goes over asmaller diameter roll which stretches the convexsurface of the blanket. Fabric is metered onto the stretched blanket andthe fabric and blanket together come in contact withthe steam heated cylinder. At this point, thestretched rubber surface contracts to its originallength and then is forced to contract an additionalamount as it forms the concave configuration of theheated drum.
  23. 23.  Since the fabric is not elastic, an extra lengthof fabric is thrust between the rubber blanketand the heated cylinder. Friction between therubber blanket and steel drum force adjacentyarns to move closer together until the unitlength of fabric become equal to the unit lengthof rubber blanket it rests on. Heat is created by constantly stretching andrelaxing the rubber blanket. The blanket iscooled by spraying water on it after the fabricexits from the unit..
  24. 24. COMPACTER HEAD
  25. 25.  The degree of shrinkage can be controlled bythe thickness of the blanket. The thicker theblanket, the greater is the stretched length atthe bend. A longer length of fabric will be fedinto the compactor causing the degree ofcompacting to be greater. To be effective, the degree of compactingneeded should be predetermined ahead of time.This is done by characterizing the shrinkingbehavior of the fabric by laundering. The degreeof compacting should not exceed the degree ofshrinking otherwise over-compacting will causethe fabric to "grow" when relaxed. This is asmuch a disadvantage as is shrinkage.
  26. 26. DECATING This process is mainly carried out on wool byexploiting its elastic properties in hot and wetconditions by the direct action of the steam onthe fabric. 1) dimensional stability; 2) setting of pile after raising; 3) reduction of possible glazing effect aftercalendering, thank to the swelling caused by steam blown onfibres; 4) modification of the hand, which is much more consistentafter the treatment; 5) pre-stabilisation to autoclave dyeing
  27. 27. SEMI-DECATING Semi-decating is a bach process requiring three steps: 1. winding the fabric onto a perforated cylinder between a cotton decating apron, 2. steaming and followed by cooling the fabric 3. unwinding and batching the finished fabric. The fabric be wound onto a perforated drum between theinterleaving cotton decating apron to form a reasonably thick roll. Steam is forced through the roll (inside - out) for several minutes toprovide moisture and heat. Compressed air is then blown through the roll in much the samemanner as the steam to remove some of the moisture and cool downthe fabric. To insure that the effect is uniform from the inside tothe outside of the roll, the fabric and blanket are rewound ontoanother perforated drum so that the outside layers become theinside layers and the cycle is repeated. At the end of the cycle, the fabric and blanket are separated andwound into individual rolls.
  28. 28. CONTINUOUS DECATING
  29. 29. WATER REPELLENT FINISHWATER PROOF FINISH
  30. 30. WATER REPELLENT FINISH Water repellent are chemical finish Resist the penetration of water into or throughthe fabric Permits the passage of moisture or air throughthe fabric Methods The yarns are coated with water repellent materiallike wax The water repellent do not permit the water drop tospread and penetrate Could be of durable and non-durable types
  31. 31.  Non-durable repellents are easily removed inlaundering or drycleaning Non-durable repellents do not providesatisfactory resistance to oily liquids Durable repellent finish can be either repellentto water or oil or both Flurocarbon compounds have excellent durabilityto both drycleaning and laundering
  32. 32. WATER PROOF FINISH A water-proof fabric, unlike a water repellent fabric, iscompletely moisture proofed The fabric is coated or laminated with a film of natural orsynthetic rubber or plastic, such as vinyl or polyurethane Water proof fabrics are not necessarily more desirable thanwater-repellent fabrics Water proof fabrics are uncomfortable Water proof fabric possesses a rather firm, non-rapable hand
  33. 33. PARAFFIN WAXES The oldest and most economical way to make a fabricwater repellent is to coat it with paraffin wax. Solventsolutions, molten coatings and wax emulsions are ways ofapplying wax to fabrics. Of these, wax emulsions are themost convenient products for finishing fabrics. Animportant consideration in making water repellent waxemulsion is that the emulsifying system not detract fromthe hydrophobic character of paraffin. Either non-rewetting emulsifiers or some means of deactivating thehydrophilic group after the fabric is impregnated with thefinish must be used. Paraffin wax melts and wicks into the fabric when thefabric is heated. This will cause most of the fibers to becovered with a thin layer of wax, especially those that areexposed to water, and the fabric will have excellent waterrepellent properties. The major disadvantage of wax waterrepellents is poor durability. Wax is easily abraded bymechanical action and wax dissolves in dry cleaning fluids.It is also removed by laundry processes.
  34. 34. WAX EMULSION COMPOSITION A typical wax emulsion consistsof paraffin wax as thehydrophobe, an emulsifyingagent, an emulsion stabilizer(protective colloid) and analuminum or zirconium salt todeactivate the emulsifyingagent when the fabric isheated.
  35. 35. SILICONE WATER REPELLENT Resinous polysiloxanes, Are more resistant to abrasion and less solublein dry-cleaning fluids or laundry products. Aqueous pH is maintained between pH 3-4, stable emulsions can be prepared. When theseemulsions are applied to a fabric with a tincatalyst (e.g. dibutyltin-dilaurate), the Si-Hgroup hydrolyzes and condenses to a three-dimensional resinous polymer, making the fabrichighly water repellent.
  36. 36. APPLICATION TO FABRICS Silicone finishes are applied to fabrics either froman organic solvent or from water as an emulsion.When cationic emulsifiers are used to make anemulsion, the finish may be applied by exhaustionsince the negative fiber surface charges attractpositively charged particles. Generallyhowever, silicone water repellents are co applied witha durable press finish. Durable press resins enhancethe durability of the water-repellent finish. Silicone repellents are also used to make upholsteredfurniture stain repellent. Chlorinated solventsolutions are sprayed onto upholstery by the retaileras a customer option. The fabric is resistant to waterborne stains such as coffee and soft drinks.
  37. 37. FLUOROCHEMICAL REPELLENTS Fluorochemical repellents are unique in that theyconfer both oil and water repellency to fabrics. The ability of fluorochemicals to repel oils is relatedto their low surface energy which depends on thestructure of the fluorocarbon segment, thenonfluorinated segment of the molecule, theorientation of the fluorocarbon tail and thedistribution and amount of fluorocarbon on fibers. Commercial fluorochemical repellents are fluorine-containing vinyl or acrylic polymers. This is aconvenient method of affixing perfluoro side chainsto fiber surfaces that can orient air-ward and give areasonably close packed surface of -CF2- and -CF3groups.
  38. 38. RECIPE A typical formulation forpolyester-cotton rainwear andouterwear is given. The finish is applied by paddingthe formulation ontofabric, drying at 120°C andcuring 1-3 minutes at 150-182oC. The fabric will give a 100 sprayrating initially and an 80 ratingafter 5 home laundering-tumble drying cycles. An 80spray rating is expected afterone dry cleaning cycle. In addition, oil repellencyrating of 5 initially and 4 afterlaundering or dry cleaning isexpected.
  39. 39. SPRAY TEST
  40. 40.  100 - No sticking on wetting of upper surface 90 - Slight random sticking or wetting of upper surface 80 - Wetting of upper surface at spray points 70 - Partial wetting of whole of upper surface 50 - Complete wetting of whole of upper surface 0 - Complete wetting of whole upper and lower surface
  41. 41. FLAME RETARDANT FINISH
  42. 42. FLAME RETARDANT FINISH When solid materials are heated, physical andchemical changes occur at specific temperaturesdepending on the chemical make-up of the solid. Thermoplastic polymers soften at the glass transitiontemperature (Tg), Melt at Tm. Both thermoplastic and non-thermoplastic solids willchemically decompose (pyrolyze) into lower molecularweight fragments. Chemical changes begin at Tp andcontinue through the temperature at which combustionoccurs (Tc). Limiting Oxygen Index (LOI). This is the amount ofoxygen in the fuel mix needed to support combustion.The higher the number, the more difficult it is forcombustion to occur.
  43. 43. NONDURABLES FLAME RETARDENT 1. Boric Acid/Borax. 2. Diammonium Phosphate and Phosphoric Acid 3. Sulfamic Acid and Ammonium Sulfamate
  44. 44. DURABLE FLAME RETARDANT 1. Tetrakis(hydroxymethyl)PhosphoniumDerivatives Tetrakis(hydroxymethyl) phosphonium Chloride(THPC) b. THPC-Urea Precondensate Tetrakis(hydroxymethyl)phosphonium Hydroxide(THPOH) 2. N-Methyloldimethyl Phosphonopropioamide(PYROVATEX CP) 3. Phosphonic and Phosphoric Acid Derivatives
  45. 45.  Limiting oxygen index (loi)Is the minimum concentration ofoxygen, expressed as a percentage, that willsupport combustion of a polymer. It is measuredby passing a mixture of oxygen and nitrogen overa burning specimen, and reducing the oxygenlevel until a critical level is reached
  46. 46. CALENDARING
  47. 47. CALENDRING Calendaring is a process where fabric is compressedby passing it between twoor more rolls undercontrolled conditions of time, temperature andpressure. It is a type of mechanical finish Produces different types of surface appearance1. Simple calendering2. Glazed calendering3. Ciŕe calendering4. Embossed calendering5. Moiré calendering6. Schreiner calendering
  48. 48. OBJECTS OF CALENDERING To improve the fabric handle and to impart asmooth silky touch to the fabric To compress the fabric and reduce its thickness To reduce the air permeability by closing thethreads To increase the luster To reduce the yarn slippage To increase the opacity of the fabric Surface patterning by embossing
  49. 49. 1. SIMPLE CALENDERING It is a high speed, high pressure pressing of fabric (100 yds /min) The high pressure flattens the yarn Smoothen the fabric Increases fabric lustre (fabric cover increases and morelight is reflected) Used for woven plain or twill weaves Over-calendering however is to be avoided Yarns weakened out due to very high pressure It is a temporary finish Yarns return to its natural cross section after firstlaundering
  50. 50. 2. GLAZED CALENDERING It is a calendering finish to produce highly glazed / shinedpolished cotton The calender machine used is a friction calender One cylinder of highly polished steel cylinder rotating atspeed much higher than the fabric passing through it Fabrics are first treated with starches or resins beforecalendering The spaces between the yarns are thus filled up and glazedappearance is obtained Glazed calendering using starch are semi-durable Glazed calendering using resins are durable
  51. 51. 3. CIŔE CALENDERING It is a type of glazed calendering Here, the friction rollerrotates at speed much greater than ordinary friction calendering The resulatant fabric become highly lustrous and takes on a wetlookCotton, rayon, polyester, nylon and blends can be given cirefinish Fabrics are however, treated with waxes and resins beforefriction calendering Highly polished effect is produced When thermoplastic fabrics are ciŕe finished, they becomesmoderately water-repellent Due to flattening Due to partially fusing of fibres
  52. 52. 4. EMBOSSED CALENDERING It is a calendering in which a three-dimensionaldesign is created on a fabric This is done on a special embossing calender inwhich the roller cylinder is engraved with theembossing design The pattern is then pushed or shaped into the clothwhen the fabric passes between the rollers Some embossed fabrics are made to imitate morecostly woven jacquard or dobby designs
  53. 53.  Embossed patterns of fabrics treated withresins and cured after embossing are durable Embossing of fabrics of thermoplastic fibres arepermanent because the heated metal roll heat-sets the design
  54. 54. 5. MOIRÉ CALENDERING The moiré finish produces a wood-grain design on the face sizeof the fabric Moiré finish can be temporary, durable or permanent Cotton or rayon moiré finish is temporary withoutpretreatment with resin Durable moiré finish requires initial resin treatment followedby calendering Moiré finish on thermoplastic fiber fabrics are permanent ifa heated roller is used for calendering Methods of producing moiŕe Using engraved cylinder Using smooth calender roller
  55. 55.  Using engraved cylinder In this case engraved roller is used on the calender roller Calender roller flattens one part of the fabric more thanother, causing different light reflectance The different light reflectance cause moire effect Definite repeat pattern moiŕe is produced Using smooth calender rollers Two fabrics, each face to face, are fed through the calender Ribbed fabrics are mainly required for this The high pressure on the calender rolls causes the rib tosqueeze into each other in certain areas Creates light reflectance pattern which produces moiŕeeffect The effect is completely random and has no specific pattern
  56. 56. 6. SCHREINER CALENDERING Schreiner calendering produces a low, soft-key lustre on thefabric surface Distinct from the high glaze of the glazing calender or thelustre shine of the simple calender To produce this effect, one of the steel cylinders of thecalender is embossed with fine diagonal lines. These embossingare barely visible in naked eye Widely used on cotton & cotton/polyester sateen Schreiner calendering may be permanent, durable or temporaryfinish Is permanent if the fibre is thermoplastic Is durable if the fabric is resin treated but not cured Is temporary if the fibre is non-thermoplastic and nottreated with resin
  57. 57. FULLING During the traditional milling operation, fabrics of combed,carded or blended wool (nonscoured, scoured or carbonisedand neutralised), at about 40°C, are soaked and in presence ofspecial surfactants, are subjected to continuous pressure bothin weft and warp direction. Under these conditions, woolfibres tend to felt, thus causing fabric shrinkage and asubsequent dynamic compacting. After this operation, thematerial must be washed to remove dirty water and thechemicals used. Fulling is a permanent finish Used in wool fabrics Gradual or progressive felting of wool Done by carefully and controlled scouring or laundering The resultant fulled fabric is more compact and moresmoother Woollens are frequently heavily fulled Fabrics of worsted are usually very lightly fulled
  58. 58. MILLING MACHINES
  59. 59. NAPPING It is a mechanical finish Fibres being raised from woven/knitted fabrics byrotating, bristled, wire covered brushes Overall effect is a raised fibres from fabric surface Example: cotton flannel, rayon flannel, woollen and worstednapped fabric like kersey, melton Napped fabrics have softer handle Better insulation properties due to more air entrapment Mainly used as blankets, winter clothing
  60. 60. RAISING (NAPPING) MACHINE:1: ROLLER; 2: ROLLERS EQUIPPED WITH HOOKS;3: FABRIC;4: NIB CLEANING BRUSHES;5: FABRIC TENSION ADJUSTMENT
  61. 61. RAISING THE FACE AND BACK OF THE FABRIC:A) SCHEME; B) VIEW
  62. 62.  Problems are Low resiliency and hence premature flattening occurs Nap can be partially restored by frequent brushing Subject to pilling Rapid wear at abrasive points (like sleeveends, elbows, button holes etc.) Not recommended for hard wear
  63. 63. SUEDING It is a mechanical finish Similar to napping Produces a soft, suede-like surface Sand paper like material is used instead ofrotating wire covered cylinder
  64. 64. PLISSÉ Plissé is the name of the finish as well as the fabric producedwith this finish Permanent and chemical finish Sodium hydroxide is printed on cotton fabric as a paste Fabric shrinks only where the sodium hydroxide isapplied, producing a puckered effect Plissé fabric do not require ironing When the sodium hydroxide is applied as lengthwise stripes, thefabric puckers and takes on the appearance of seersucker
  65. 65. Seersucker Lengthwise stripped puckered effect Produced by alternative stripes of loose and tightwarp yarns Plisse is a cheaper imitation of seersucker Plisse does not have that depth degree of pucker thatis common to seersucker Plisse puckers stretched out flat but seersucker donot
  66. 66. SHEARING A process to used to cut off surface fibers onfabrics Uniforms the surface of napped fabrics to provideuniform pile height High-speed cutting machine cuts the piles similar tothat of a lawn mower The blades in the machine are stationary and thefabric moves through the cutting blade
  67. 67. STIFFENING Some fabrics need to be made stiffer and more crisp as per asthe end use Stiffening agents are applied to the cloth to build up thefollowing properties To increase the weight of the fabric To improve the thickness To improve lustreBut, their effect is temporary and once the fabric iswashed, most of the finishes are removed
  68. 68. STIFFENING Stiffening agents Starches – finishing of cotton cloth. Ex: potato , wheat, corn Dextrines – used for dyed and printed fabrics. No undueeffect on the dye or print. Natural gum – mainly used in printing as well as finishingprocess Modified cellulose – CMC ResinsAcid stiffeningFine yarn cotton fabrics can be finished to be both stiff andtransparent by a process known as acid stiffening. It involves rapidimmersion in sulphuric acid, followed by immediate neutralization in sodiumhydroxide. The finish is permanent. This finish is also known as Organdifinish or Parchmentisation.
  69. 69. SOFTENING Required for more pleasant hand and betterdrapability Fabrics are harsher and stiffer because of theirconstruction or due to some prior finishing process Softening can be done by either mechanical orchemical process Simple calendering softens hand, but it is temporary
  70. 70.  Silicone compounds are used mostly as softner Silicone finish is a durable finish and require curing Different types of emulsified oils and waxes can beused but they are semi-durable finish
  71. 71.  Different types of softners Anionic softners Cationic softners Non-ionic softners Reactive softners Emulsion softners Silicon softners
  72. 72.  Anionic softners This is not fast to wash Compatible with resin Used in temporary finish with starch and cationicproduct Ex; Sulphonated oils, fatty alcohol sulphates etc. Non-ionic softners Have excellent stability against yellowing Not fast to dyeing No effect on in the shade of dyestuff
  73. 73.  Cationic softners Substantive to cellulosic material Therefore, remain on cloth for few washes Produce yellowing on white fabrics Compatible with resins Reactive softners Durable softners React chemically with the –OH groups of cellulose High cost Yellowing of treated fabric Toxic
  74. 74.  Emulsion softners Popular because it reduces the loss of tear strength onresin finish Fast to washing Give fuller appearance Silicon softners Recently most used softners These are the manmade polymers based on the framework of alternate silicon and oxygen bonds with organicsubstituents attached to silicone
  75. 75. MECHANICAL SOFTENING MACHINE
  76. 76. SOIL RELEASE FINISH
  77. 77. SOIL RELEASE FINISH How?? Making the fibres more absorbent (hydrophilic) Permitting better wettability for improved soil removal Done by using hydrophilic finishes Facilitates soil release during washing Prevent soil redeposition Also, reduce static charge by maintaining moisture on thefabric surface Thus soil attraction during wear can be reduced Mainly observed in polyester fabrics
  78. 78. SOIL RELEASE FINISH What is soiling of textiles? Textile material getting attracted to dirt or soil Development of static charge electricity tohydrophilic textiles, making them prone to soiling Re-deposition of soil during washing The soils cannot be readily removed Hydrophobic materials are not wetted properlyduring laundering
  79. 79. SOIL RELEASE FINISH What is soiling of textiles? Soil release finish is a chemical finish This permit easy removal of soil with ordinary laundering Hydrophilic fibres and fabrics with resin finish are not easily wet able Hence, stains of oily nature are not removed easily Soil release finish increases the hydrophilicity of the material andincreases wetability Soil release finish also improves the antistatic properties, fabricdrapability and comfort
  80. 80. WRINKLE RESISTANT FINISH
  81. 81. WRINKLE RESISTANCE FINISH The ability of the fabric to resist the formation of crease or wrinklewhen slightly squeezed is known as ‘crease resistance’ fabrics The ability of a fabric to recover from a definite degree from creasing iscalled crease recovery Finish to reduce the undue wrinkles on fabric or garments Cotton, rayon and flax are more susceptible to wrinkle Wrinkle occurs due to the hydrogen bonds of the cellulosic molecules inthe amorphous region Due to application of heat or moisture, the hydrogen bond breaks and newhydrogen bond occurs at new dimension Therefore wrinkling can be reduced if the hydrogen bond formation canbe reduced
  82. 82.  Formaldehyde DMU ( Di-methylol urea) DMEU (Di-methylol ethylene urea) DMDHEU (Di-methylol di-hydroxyl ethyleneurea) Modified DMDHEU (Di-methylol di-hydroxylethylene urea)
  83. 83. APPLICATION TECHNIQUE Dry Process The classic process: the fabric is impregnated bymeans of a padding unit (the quantity of finishistuned by modifying the liquor concentration and thesqueezing ratio) and dried at 100-120 °C in a stenter. The cross-linking process occurs in the stenter, attemperatures varying according to the type of cross-linking agent used (generally 4-5 minutes at 150-160°C). Double treatment: the fabric is impregnated with asoftener and dried at 100- 130 °C.
  84. 84. HUMID PROCESS The fabric is wetted by means of a padding unitwith a cross-linking agent and a catalyst solution; Then 6-8% of residual moisture is removed fromcotton (or 10-15% from other staple goods.) Thefabric is then wound up on a roll, covered with apolyethylene sheet and left 16-24 hours to restat ambient temperature. Strong catalysts must be used for this process. The final effect depends on the residualmoisture: in case of low residual moisturecontent, the results will be similar to thoseobtained with the dry process whereas if theresidual moisture content is high, the result isvery similar to the cross-linking effect on wetsubstrates.
  85. 85. FRAGRANCE FINISH
  86. 86. FRAGRANCE FINISH Microencapsulation is a useful method for protecting variousfunctional finishes on textiles. As the capsules do not haveaffinity to fabrics, a binder should be used to fix thecapsules for the purpose of finish durability. Conventional fixation is a thermal process, in which a fabric iscured at 130-170°C for 1-10 minutes to make the componentsof the binder cross-link together, and tightly fix capsules onthe fabric. During curing, however, the aroma inside capsules can be lostthrough quick evaporation and swelling to escape or break thecapsule. The loss from capsules can seriously reduce theamount of aroma on the fabric and decrease the durability. An aroma capsule finished cotton fabric treated by a thermalcuring process can only bear 25 wash cycles. To avoid thethermal process, an UV resin can be used to fix capsulesbecause the resin can be cured under UV light at lowtemperatures in seconds. If a cotton fabric is finished withthe selected aroma capsule and UV resin, and cured under theoptimal conditions, the aroma function can withstand 50 washcycles. Whiteness and stiffness of the finished fabrics werealso examined.
  87. 87. ANTISTATIC FINISH
  88. 88. ANTISTATIC FINISH Synthetic fibres of hydrophobic nature are prone to generationof static charges This problem is very troublesome while processing the fabric athigh speed in dry state Antistatic agents are used Antistatic agents absorb small amount of moisture from theatmosphere, thus reducing the dryness of the fabric Antistatic finishes are semi-durable Washes out at several launderings or drycleanings Permanent antistatic effects are obtainable manufacturedfibres which are specially modified for this purpose (Ex: AntronIII nylon fibre by Dupont & Cadon nylon fibres by Monsanto)
  89. 89. Pilling
  90. 90.  Anti-pilling finishes: Pilling is an unpleasant phenomenon associated with spunyarn fabrics especially when they contain synthetics. Synthetic fibers are more readily brought to the surfaceof fabric due to their smooth surface and circular crosssection and due to their higher tensile strength andabrasion resistance, the pills formed take a long time to beabraded by wear. With knit fabric, two more problems occur, viz., "picking"where the abrasion individual fibers work themselves outof yarn loops onto the surface when garment catches apointed or rough object.
  91. 91. • Permanent Anti-static effects:• Antistatic finish for synthetic textiles to avoid staticcharge build up & give a natural feel.• Anti-static effective chemicals are largely chemically inertand require Thermosol or heat treatment for fixingon polyester goods.• In general Thermsolable anti-static agents also have a goodsoil release action which is as permanent as the anti-staticeffect.• Anti-static finishes may also be of polyamide type beingcurable at moderate temperatures
  92. 92. • Non-Slip finishes:• Synthetic warp and weft threads in loosely woven fabricsare particularly prone to slip because of their surfacesmoothness when the structure of fabric is disturbed andappearance is no loner attractive.• To avoid this attempts are made to give the filaments arougher surface.• Silica-gel dispersions or silicic acid colloidal solutions arequite useful and they are used with advantage incombination with latex polymer or acrylates dispersions toget more permanent effect along with simultaneousimprovement in resistance to pilling or snagging.• These polymer finishes are also capable of imparting a softand smooth handle to synthetic fabric without impartingwater repellency
  93. 93. WASHES Alters the look by different washing procedures Mainly used for denim and similar items to have a fadedand worn appearance Have different methods Stone washing Acid washing Enzyme washing
  94. 94.  Stone wash Stone washing transforms a new unworn garments intoused-looking faded garments Done in garment form Pumice stone are used No chemicals are used for fading Pumice stone are added to the laundry with thegarments which abrade the garment Worn look Faded colour The garment also become softer and obtain a casuallook
  95. 95.  Acid wash No acid is used Pumice stones are soaked with oxidising bleachingagent (sodium hypochlorite) Also known as ‘frosting’ or ‘ice washing’ The other procedure is same as that of the stonewash
  96. 96.  Enzyme wash Cellulase is used Added to pumice stone or can be used separately While using pumice stone soaked with enzyme the garmentis laundered with the pumice stone The cellulase attacks and weakens the cellulosic fibre The surface colour of the denim comes out and colour fadesoff
  97. 97. ROT PROOFING OF CELLULOSE Cellulosic fibres are made up of carbohydratewhich is a food for fungi and microorganisms The attack of these organism on the cellulosicmaterials cause rottening of them To protect the cellulosic materials from suchhazards rot-proof finishes are applied on cotton Organo-lead componds Advantages It does not affect the handle of the fabric It retains 100% of the fabric strength It does not discolour the fabric
  98. 98.  Hg containing antibacterial agents Can be used in cotton as well as other cellulosic materials

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