Assistant Professor em KCT
14 de Nov de 2012

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  1. Stone wash
  2. Stone wash Stone washing of denim fabric gives "Used" or "Vintage" look on the garments. This is due to the varying degree of abrasion in the garment. The traditional stone washing of denim garments normally carried out with pumice stones to achieve a soft hand and desirable look. The pumice stones having oval and round shape with a rough surface, work as an abradant in washing cycle. The variations in shape, composition, hardness and porosity gives different washing effect in the denim fabric.
  3. Stone wash Process Seq. During washing, these stones scrap off dye particles from the surface of the yarn of the denim fabric which shows a faded, worn out and brilliance effect in the denim fabric. Due to ring dyeing of denim fabric and heavy abrasion during stone washing, the fading is more apparent but less uniform. Stone washing makes the denim garments more supple so that it fits comfortably.
  4. Pumice Stones Pumice is a natural volcanic stone used for stone washing garments. It is crystallized with substantive pores. Pumice is mostly used for stone washing due to its durability to chemicals treatment, it's strength and light weight.
  5. Stone wash Process In order to get the desired washed effect, the stone should be of proper hardness, shape, and size. For heavy weight denim fabric large and hard stones are suitable and smaller and softer stones are suitable for light weight denim. Stone wt. /fabric wt. = 0.5 to 3 /1 The degree of colour fading during stone washing depends on several factors, such as, garment to stone ratio, washing time, size of stones, material to liquor ratio and load of garments. The washing time may varies from 60 - 120 min. Stones may be reused until they disintegrate completely.
  6. Limitations of Stone wash Stones may cause wear and tear of the fabric and may damage to washing machine due to abrasion of the stone. It may also create the problem of environmental disposition of waste of the grit produced by the stones. Increase the labor cost to remove stone dusts from finished garments. The denim garments is required to washed several times for complete removal of the stones. The process may cause back staining and re-deposition. The process is non-selective. Metal buttons and rivets in the denim garments as well as the drum of the washing machine get abraded which substantially reduces the quality of the garment and the life of the equipment.
  7. Synthetic Stones In order to find an alternate to pumice stone synthetic stones have been introduced. These synthetic stones are produced from abrasive material such as silicate, plastic, rubber or Portland cement. The advantages of synthetic stones in stone washing are: The major problem faced by using the pumice stone has been overcome. Synthetic stones are more durable than pumice stone and can be repeatedly used from 50-300 cycle. The washing effect may be manageably reproducible. They cause less damage to machines and garments.
  8. Perlite – An alternative to Pumice Perlite stonewash is a new stonewashing process. Perlite is a naturally occurring silicon rock, contains 2-6% of water content in it. Due to this reasons, when heated at a particular temperature, perlite expanded 4 to 20 times of its initial volume. These properties of perlite make it suitable for stonewashing process. Perlite offers less damage to washing machine than pumice stones. It gives better supple and softer finish to denim garments.
  9. Acid wash
  10. Acid Wash Acid wash on denim jeans is becoming very popular due to its significant contrasts and attractive appearance in color. Acid wash can be carried on Indigo & Sulphur base fabric garments. Acid wash is a chemical wash on denim which stripped the top layer of color and make a white surface while the color remained in the lower layers of the material, giving it a faded look. This wash is being carried out by pre soaking stones in bleach and then followed by neutralization. Acid wash of denim garment normally carried out by tumbling the garments with pumice stones presoaked in a solution which contains sodium hypochlorite (5 to 10%) or potassium permanganate (3 to 6%). This cause localized bleaching which produce non uniform sharp blue/white contrast.
  11. Acid Wash Garments In this wash addition of water is not required. The color contrast can be increased by optical brightening treatment.
  12. Acid Wash – Process Sequence
  13. Acid Wash – Limitations & Remedies Limitations of acid wash: Acid washed, indigo dyed denim has a tendency to yellow after wet processing. The major cause is residual manganese due to incomplete neutralization, washing or rinsing. Remedy: Manganese is effectively removed during laundering with addition of ethelene-diamine-tetra-acetic acid as chelating agent. Acid washing jeans avoided some of problems of stone wash, but came with added dangers, expenses, and pollution.
  14. Enzyme wash & Bio Polishing
  15. Enzyme wash In order to minimize the adverse effect of stone-washing, the denim garments is washed with enzymes. The enzyme breaks the surface cellulose fibers of the denim fabric and removes during washing. During enzyme washing certain amount of indigo dye and cellulose fibers from the surface of the fabric are removed.
  16. Enzymes Enzymes are proteins, found in all living organisms, plants, as well as animals and microorganism. All organisms produce a wide range of enzymes. Enzyme washing is ecologically friendly due to the natural origins of enzymes. Enzymes basically catalyse specific chemical reactions and are known as 'bio-catalysts'. Enzymes act on living cells and can be work at atmospheric pressure and in mild temp and pH.
  17. Enzymes Lock & Key
  18. Enzymes Lock & Key The basic mechanism of enzyme reaction consists of binding of the substrate to the active site on the enzyme which causes changes in the distribution of electrons in the chemical bonds of the substrate. This ultimately causes the reactions which lead to the formation of products. The products are removed from the enzyme surface which regenerates the enzyme for another reaction cycle. The active site of enzyme has a unique geometric shape which is complementary to the geometric shape of a substrate molecule. Due to this reasons enzymes specifically react with only one or a very few similar compounds. Enzymes are highly specific and the specific action of an enzyme with a single substrate can be explained by the "lock-key theory".
  19. Enzymes Reactions Enzyme molecule has formed a complex with the substrate to catalyse a reaction. The binding sites of the enzyme recognize the corresponding domain of the substrate. After proper orientation of the molecules, the reactive site of the enzyme molecules have access to the appropriate part of the substrate molecule. When the reaction is over, the product formed quickly detach from the complex. The model of enzyme substrate elementary reactions is explained by the Michaelis-Menten mechanism.
  20. Enzymes Reactions Michaelis-Menten mechanism. The basis of the Michaelis-Menten mechanism of enzyme action. Only a fragment of the large enzyme molecule E is shown
  21. Enzymes Reactions The enzymes used in bio-stoning are "cellulases." Cellulase acts mainly on the surface of the fiber, but it leaves the inner intact. Cellulase removed by partially hydrolyzing the surface of the indigo dyed fiber of denim fabric. Cellulases are blends of selective enzymes that break down cellulose into glucose. Cellulase enzyme can be classified according to pH range in which they are more effective, such as acid, neutral and alkaline stable cellulases. The first two types are commonly used.
  22. Enzymes Reactions Acid Cellulase : pH range of 4.5 - 5.5 , temp. 50 C. Neutral cellulose : pH 6 - 7.0, temp. 55 C. Neutral cellulase is preferred to acid cellulase due to little or no back staining, less loss of strength and weight. Acid cellulase are lower in costs and shorter enzyme cycle time as compared to neutral cellulase. Cellulases are used under biological conditions of temperature 40 - 60 C and pH. Cellulase enzymes are used in stone washing process. So, less stones are required and causes less damage to the machinery and fabrics. Cellulase treatment on fabric reduce fuzz and pills, increased smoothness, softness, luster and brightness, improve fabric handle and drapeability and increase the wash down effects.
  23. Advantages of Enzymes • Cellulase is economical and environmentally friendly as compared to stone washing using pumice stones. • The percentage of fabric damages has been reduced with cellulase treatment. • The enzymatic treatment of denim fabric ensures the same result by consuming less water and time, resulting less waste and damage to machines. • The pollution, quality variability, and imperfections also reduced in enzymatic treatment. • The enzymes can be recycled.
  24. Advantages of Enzymes •The productivity of washing is increased due to the space formerly taken up by the pumice stones in the washing machines can now be filled with more jeans. •The time consumption for removing stone fragments from the denim garments has been eliminated in cellulase treatment. •The duration or number of rinse washing after enzymes treatment is less than pumice stone-washing. •A small quantity of enzyme can replace several kilograms of pumice stones during washing, which ultimately leads to less damage to garment, machine and less pumice dust. •Washed garment with soft handle and better appearance is achieved in cellulase treatment.
  25. Disadvantages of Enzymes Cellulase treatment of denim fabric having some disadvantages. There may be chances of back-staining in cellulase treatment. In order to remove the back stating, the garments are rigorously washed. This is added usage of water for the washing.
  26. Bio Wash/Polishing The appearance of natural cellulosic material, such as cotton can be improved though an enzymatic treatment. This is known as Bio-Polishing. The bio-polishing treatment remove the fuzz and pilling from the fabric surface and gives the fabric a softer and smoother handle, and superior colour brightness and glossier appearance. In Bio-polishing process cellulase enzyme which is a protein which has a specific catalytic action upon the 1,4-b-glucosidic bonds of cellulose. The cellulase enzyme molecule is too large to penetrate the interior of a cotton fiber. Hence it only act on the surface 1,4-b-glucosidic bonds. Cellulase is a complex multi-enzymatic system and it acts on cellulose in two different
  27. Mechanism of Bio Polishing Endocellulases hydrolyze the cellulose by converting it from crystalline cellulose to amorphous cellulose. The b-1,4 link inside of the cellulose polymer is cut randomly. Extremities of the polymer is cut by Exocellulases. Cellobiohydrolases exocellulases detach two units of glucose leaving cellobiose.
  28. Bio Polishing Process Conditions Bio-polishing can be carried out on cotton as well as viscose, jute, flax, ramie etc. It can be applied at any wet processing stage or in other processes. Typical process conditions is as below: Enzyme : 0.5% to 2.0% OWF pH : 5 to 5.5 Temperature : 50 to 550C Time : 30 to 60 min
  29. Enzyme Wash Bio Wash/Polishing Here we use cellulase enzymes Here we use cellulase enzymes which attack and weaken cellulose which attack and weaken cellulose (cotton). (cotton). Enzymes weaken the surface The removal of protruding fibres fibres, which are then (Hairiness) will take place. mechanically torn off during processing taking with them Enzymes weaken and break the indigo. hairs from the fabric surface. The need mechanical action to No colour fading is formed. work, often to improve the rate of abrasion they are used with No abrasion process is required. stones. Bath process and not applied with Fading due to removal of colour stones. with the fibres due to mechanical abrasion takes place. Surface will be smoothened.
  30. Sand Blasting
  31. Sand Blasting This process refers to a physical process which creates localized abrasion or colour change on the denim similar to the effect seen on well used jeans. Sand blasting technique is based on blasting an abrasive material in granular, powdered or other form through a nozzle at very high speed and pressure onto specific areas of the garment surface to be treated to give the desired distressed/ abraded/used look.
  32. Sand Blasting It is purely mechanical process, not using any chemicals. If required stone wash can be made and then sand blasting can be proceeded for different effect. It is a water free process therefore no drying required. Variety of distressed or abraded looks possible. Any number of designs could be created by special techniques.
  33. Sand Blasting Methods Microsanding There are 3 ways for this technique:  Sandblasting  Machine sanding  Hand sanding or hand brushing Used in various ways:  Flat surfaces (tables, ironing boards)  On the dummy (inflatable dummies, sometimes standing, sometimes flat, sometimes 'seated')  Various templates can be used to create a 3D effect. This process is isolated now a days due to health hazards & buyers do not like the results of sandblast because its covers the characteristics of fabric. This process being done by using different kind of sand blown to garments with air pressure to rub out the color.
  34. Ozone and Laser Fading
  35. Ozone Fading In this technique of denim washing, the garment is bleached with ozone dissolved in water in a washing machine. However this technique can also be carried out in a closed chamber by using ozone gas. The advantages of this methods are: - There is minimum loss of strength - It is a simple method and environmentally friendly. The ozonized water after laundering can easily be deozonized by UV radiation.
  36. Ozone Fading OZONE FADING - By using this technique, the garment can be bleached. - Bleaching of denim garment is done in washing machine with ozone dissolved in water. - Denim garments can also be bleached or faded by using ozone gas in closed chamber. - In the presence of UV light, there is an interaction between the hydrocarbons, oxides of nitrogen and oxygen that causes release of ozone. - Indigo dyestuff tends to fade or turn yellow due to ozone reaction.
  37. Ozone Fading Ozone induced yellowing is a major problem on denims. This is due to the sun's UV radiation. The increased concentration of NOx and SOx gases due to pollution can potentially react with ozone and reduce its concentration tremendously in the ozone layer. As a result a portion of the sun's UV radiation reaches to the earth's surface and generates ozone gas from the atmospheric oxygen. Ozone (O3) being a very strong oxidizing agent decomposes indigo dye in the following manner.
  38. Ozone Fading Based on molecular weight calculation One gram of ozone could destroy 10.9 gram of indigo dye. The ozone induced oxidation of indigo produces certain compounds which are 'isatin, anthranillic acid, and the complex of the two products.' which is yellow in colour. This is the reason of yellowing due to ozone fading. The factors influenced in the yellowing of indigo dyed garments: •Position of the dyestuff in the fibre •Absorption and diffusion of moisture in to the fibre •Humidity •Protective chemicals on the fibre •Ozone concentration;
  39. Factors influenced in the yellowing of indigo dyed garments Position of dyestuff in the fibre: The yellowing due to ozone is directly proportional to the amount of back staining generated in the wash process. Back staining is the re- deposition of indigo dye released during various wash process. Re- deposited dye has more loose sites for oxidation resulting in the yellowing of denim garments, the use of anti re-deposition chemicals in the de-size and abrasion baths can prevent the re-deposition of the released dye by suspending the dye particles in the bath and not allowing the re-deposition to happen. Absorption and diffusion of moisture in to the fibre: The increase in humidity accelerates ozone fading of indigo dye stuff as high humidity give rise to a surface water film that increases the ozone absorption rate. This is due to the increased surface concentration and also the increased rate of diffusion in the fibre. Fibres swell after the absorption of moisture and the swollen fibres are always in a more receptive condition. So the problem of ozone fading will be more prominent in high humidity regions
  40. Factors influenced in the yellowing of indigo dyed garments Humidity: High humidity raises the absorption rate since the fibre is more receptive due to swelling. With 0.2 ppm of ozone level, the time to fail (2.5 rating on AATCC -scale) increases substantially as the relative humidity increases. At the RH of 80, the time to fail would be 34 hours and this would fall in to 16 hours at RH 85. Protective chemicals on the fibre: The conventional oxidants such as Sodium Bisulfite, Ethylene Diamine Derivatives etc, will provide only short term protection against ozone fading. This type of anti oxidants undergo very rapid chemical de-composition and do not provide the protection required when the garments are stored for extended periods of time in high ozone concentration. Selected amine based softeners can provide the protection for ozone fading. Since the softeners are applied substantially in large quantities as compared to anti oxidants, they can provide protection for an extended period of time.
  41. Factors influenced in the yellowing of indigo dyed garments The usage rate of anti-ozone softeners are highly depened on the activity of the product. The rate at which the cationic softener exhausts on the cellulose is related to the pH of the softener bath. Anti-ozonates are solubilized by lowering the pH of the product. Once in solution an increase in pH reduces the solubility of the softener and the exhaust rate increases significantly. As the pH of the bath reach certain point (pH - 8 or above), the softener exhausts so rapidly that it plates out on the surface of the fabric. The excess softener on the surface has a clammy, tacky feel and will yellow severely when dried. For optimum exhaustion of this product on to the garment, the temperature should be kept in between 45 - 5 5°C and pH in between 6 to 6.5. Usage of anti-ozone softener to prevent the ozone fading in indigo denim is not the complete solution. Thorough study for the reason for yellowing must be done before going for any remedial measures - for the complete control.
  42. Factors influenced in the yellowing of indigo dyed garments The other reasons of denim garment yellowing: This is the yellow discoloration thattextiles can develop during processing, use or storage. Since this yellow discoloration, which appears on the fabric on low intensity, it can be visible only on white and pastel shades. Dark shades are also affected, as colour becomes dull. There are many reasons for this yellowing. •Yellowing due to softeners; •Use of fluorescent whitening compounds; •Phenolic yellowing;
  43. Factors influenced in the yellowing of indigo dyed garments Yellowing due to softeners; Cationic and silicone softeners are commonly used to impart a good handle to the fabric. Both these softeners generally contain primary, secondary and tertiary amines and some times amides also. All these groups contain Hydrogen atom attached to Nitrogen atom. The former is susceptible to substitution and can be replaced by chlorine and form chloramines. Chloramines being yellow in colour impart yellowness to the fabric. Most of the commercial detergents contain carriers of chlorine bleaches. So each domestic wash the fabric tends to yellow more. Also the amines and amides are nitrogen-based groups can very well oxidized to nitrogen oxides if the finished fabric is over heated. Even during the normal drying of the garment/ fabric these groups can be oxidized and can produce different oxides of nitrogen. Nitrogen oxides are brownish in colour and at very low concentrations they seem yellow. Use of fluorescent whitening compounds; Fluorescent whitening agents are used to improve the whiteness of fabrics, these fluorescent whitening agents absorbs the UV light and emit it in a visible region. This emitted light is blue white in colour and mask the yellow colour of the material.
  44. Laser Fading Laser marking/Spray painting is a computer controlled technique through which different patterns or designs, such pictures, images, lines, text etc., can be developed on denim garments. It is also called spray painting in denims. In this technique chemicals or pigments is sprayed on the fabric in order to get different pattern on the garments. This is followed by curing of the garment.
  45. Laser Fading
  46. Laser Fading - Advantages The advantages of the systems is: •It is a water free process. Hence it is an It is an ecological and economical process. There is zero effluent discharge •As this process in computer controlled, the chances of human error is negligible. •This system having excellent reproducibility and higher productivity. •The machine requires less maintenance and cleaning. •Consuming less time. •This technique having no adverse effect on fabric strength.
  47. Over-Dyed / Tinted Denim Over-dyeing / tinting of denim is an additional dyeing treatment which is normally carried out on jeans after sewn. This add another tone of color to the jeans. Normally denim garments is over-dyed with yellowish dye for appearing dirty look. Tinted / over-dyed denim garments shows a used / vintage & muddy look to the garments. Tinting of denim garment normally carried out after the stone wash process. During tinting, a little amount of tint or color is added to the garment in order to change the hue/cast/tone of indigo shade. However, when the quantity of tint color increases, it cover up indigo.
  48. Over-Dyed / Tinted Denim There are various types of dyes used for over-dyeing / tinting purpose, such as: -Direct Dyes -Reactive Dyes -Pigment Dyes -Sulphur Dyes Tinting process normally taken 5 to 15 minutes. This is followed by dye fixing & clean up of superficial dye. Tinting of denim garment normally carried out after stone wash process. However this process consumes more water and chemical.
  49. Over-Dyed / Tinted Denim An alternative methods has been developed, in which novel colour based enzymes have been used. This process allows tinting and stone washing to be carried out in a single bath. The advantages of the new technique are: Consumes less water, energy and takes less process time to achieve tinted look. No extra chemical used in this process. Chances of patches or unevenness in the garment is almost nil.
  50. Stretch Denim
  51. Stretch Denim Stretch denim is made by combining elastan fiber with cotton. Spandex and Lycra are two of the most commonly used elastics. This is what gives the denim its stretch. Spandex was first created in 1959 by Joseph Shivers, a chemist. The elastic was immediately incorporated in the fashion industry, and in the 1970s it was combined with denim. Today, every jeans manufacturer has its own version of stretch denim. Stretch denim jeans have the ability to conform to your body's shape each time you put them on. With most denim, it takes time to "wear in" a pair of jeans so they fit perfectly. The elastan fiber makes the jeans stretch, so they can fit right every time.
  52. Stretch Denim Typical Application of Spandex Lycra: The Stretch Property can be achieved by insertion of Elastromeric yarn or filament in the stage of weaving. It is normally applied in the weft direction. Difficult to insert through warp way direction. Though the stretch property required in the width way, it is effective in the weft way insertion. Normally, monofilament of 20 Den, 40 Den, 70 Den and 100 Deniers are used depends upon the type of denim as well as the stretch required. A heat setting process is required before any wet processing carried out for the stretch denim fabrics to control the stability of Lycra. It will not be affected by any of the chemicals applied on the denim garments. But, the stone wash and sand blasting techniques may abrade the lycra filament tends to breakage of lycra. Gentle application is required in this finishes.
  53. Stretch Denim Warp way Stretch: For stretch denim, core spun yarns are generally employed. The core yarns are elastomeric filaments, the cover yarns are cotton yarns made generally by open end spinning. During core spinning, the elastomeric filaments are stretched by 300- 400 per cent. On contraction of the filaments after the process, stretchability will develop on the core spun yarns so formed. In some cases, for cost reduction, wrap cover yarns in which case two or more wrapping yarns are wrapped round the core elastomeric filaments are used.
  54. Peach Finish
  55. Peach Skin Effect Subjecting the fabric (either cotton or its synthetic blends) to emery wheels, makes the surface velvet like. This is a special finish mostly used in garments Peach finish will create dense and short hairs on surface of fabrics. This will make fabrics feel soft, delicate and smooth, suitable to all types of garments. With the character of soft, rich and warm hand feeling, the peach product is one of the most popular finishes on fabric in recent years. This finish will turn garments into natural and archaized after washing. Mingshi was equipped with several kinds of peach finishing machines, such as carbonized peach, sand peach and brush etc.
  56. Peach Skin Effect - Features Features: 1) Micro fiber is also called peach skin, famous for its soft hand feel. 2) It can be processed by printing and PA and PU coating. 3) It is widely used for jackets, pants and sportswear. 4) After the printing of beautiful patterns, it is always used for beach-shorts.
  57. Vintage Denim
  58. Vintage Denim Vintage Denim It is a type of denim washing in which the denim garments is subjected to heavy stonewashing or a cellulose enzyme wash, with or without bleach for showing an old and worn out look.
  59. Marble Wash by Bleaching
  60. Marble Wash by bleaching Denim bleaching normally carried out with a strong oxidative bleaching agent such as sodium hypochlorite or KMnO4. Bleaching may be carried out with or without the addition of stone. The bleaching washing effect and de- coloration usually depends on strength of the bleach liquor, liquor quantity, temperature and treatment time. The bleached fabric materials should be properly antichlored or after washed with peroxide to reduced the subsequent yellowing or tendering of the bleached denim fabric.
  61. Marble Wash by bleaching NaOCl Bleach • The bath material to liquor ratio is set at 10:1 and temp. at 140°F. • Add 0.5% owg of Soda Ash • Add 20 - 30 g/l. of Sodium Hypochlorite 12% • Bleaching to be carried out for 10 - 20 minutes with comparing to the wet standard, • Drop and rinse Antichloring Antichloring treatment is required as traces of NaOCl left on the fabric which will form hypochlorous acid. This may consequently yellow and weakens the fabric. Antichloring with hydrogen peroxide brightens undyed cotton, increase the fabric contrast, has no significant odor. Typical steps include the following: • Set the bath temp. at 140°F. • pH of the bath to be adjusted at 9 with soda ash, • Add 1 g/l hydrogen peroxide 50%, and run for 10 min. • Drop and rinse
  62. Marble Wash
  63. Marble Wash Limitations of bleaching: There are some limitations of bleaching, such as: •The same level of bleaching is very difficult to achieve in repeated runs. •Bleaching treatment sometimes damage to cellulose resulting in strength losses and or pinholes at the seam, pocket, etc. •Bleaching liquor is harmful to human health. This may also causes corrosion to the machine parts. •Bleaching treatment needs antichlor treatment in order to eliminate the subsequent yellowness to the fabric.
  64. Quick Wash Denim In normal indigo dyed denim is associated with various problems during washing. The denim fabric manufacturer are in search to developed a new dyeing method in which the wash cycle can be minimizes. In this regard, Quick wash denim has been introduced in which the fabric is dyed with modified technique of dyeing, so that during wash cycle, indigo dye can be removed easily during a shorter washing cycle. Quick wash treatment procedure consume less water and chemicals and required less time for washing, retaining fabric strength. By controlling the ionic form of indigo and cellulose in the dye- bath, the uniformity of indigo dyeing can be achieved. The alkalis used and pH conditions of indigo dye-bath produce stable color yield.
  65. Quick Wash Denim Advantages of quick wash denim 1.Quick wash denim requires less indigo dye. The washing treatment also requires less enzymes and oxidizing agent. Hence it is an economical and environment friendly process. 2. The development of streaks in garments after washing has been avoided by using a modified alkali-ph controlled system giving uniformity of shade. 3. The washing time is 20-30% less than conventional denim.
  66. Dextroes-Caustic Wash
  67. Dextroes – Caustic Wash In case of Caustic wash, pre-treatment and printing of the garments fabric is little bit different then the normal process. Dextrose based reducing agent designed to reduce indigo dye on the garment . Normally printing on fabric is done after pre-treatment of grey fabric that is desizing, scouring and bleaching. But in case of caustic wash or Dextroes-Caustic wash, printing is done on the fabric without pre-treatment of the fabric. These fabrics are used manufacture garments. Then the garments are subjected to caustic wash. During caustic wash 20% – 30% pigment is washed out, as a result different color fading affect is produced in the garments.
  68. Dextroes – Caustic Wash Recipe Making of Caustic Wash : Dextroes = 0.8 – 1% Caustic = 4%. Soda Ash = 2% Detergent = 1% H2O2 = 4% Stabilizer = 2% M:L =1:5 Temperature = 700C Time = 90 min During this processing time, impurities and size materials present in the garment is removed together with some portion of pigment. Hydrogen peroxide breaks down and produces per hydroxyl ions which takes part in bleaching and reduces the color intensity of the pigment. Neutralising by 1% Acetic acid and softener treatment will be given at 0.1 to 0.5%.
  69. Crush Finish
  70. Crush Finish or 3D Effect Resin ( Formaldehyde free ) being used for achieving 3D effect ( 3 Dimensional ), Rigid Look etc. This process can be done by spraying or dipping the garments in to Resin, Catalyst, Silicone & PU solution in right combination according to the fabric strength & desired effect needed. After application of resin solution in right proportion, make manual designing as needed on the thigh, hip & back knee area to get 3Dimentional effect. After making it , it should be manually dried with hot press or hair dryer & then must be cured in oven at right temperature, time as mentioned in resin product manual.
  71. Crush Finish or 3D Effect If resin not cured properly , 3 D effect will not be permanent & can cause skin irritation/rashes to the wearer. Highly skilled operators needs to execute this process in order to get consistency & uniformity. Whole garment can have crushed look by resin dip & crushed manually followed by oven curing. Silicone plays an important role in getting softer hand after oven. Special streaky effect & Crackles also being done by applying resin on desired area followed by scraping & pp spray then neutralization.
  72. Pseudo Denim The production of pseudo denim is based on transfer of a chemical finish to the raised ridges of a natural denim fabric. The chemical finish imparts a cationic character to the raised ridges. The cationic character imparted to the raised ridges permits selective dyeability to these areas of the fabric. The transfer technique used for the production of pseudo denim is the loop pad process. The fabric used for the transfer technique is a right hand 3/1-twill denim.
  73. Pseudo Denim This natural undyed denim is then desized, scoured, bleached and mercerised. If the fabric has a grafted quaternary or amine group, dyeing is performed under acidic conditions with a reactive or acid dye. The specific formulation consists of DMDHEU, magnesium chloride hexahydrate, choline chloride and wetting agent. The solution is then applied to the face of the denim fabric with a wet pick up 8-17 per cent. Once the fabric is dried, cured and washed, the raised fabric ridges have selective dye affinity. The dyes usually used are blue and red reactive dyes.
  74. Stretch denim