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Garment washing

  2. GARMENT FINISH  Unless any product is characterized by value addition it is now impossible to survive in this highly competitive world market. Processing is important to make a usable but finishing gives value addition to it.  It makes garments attractive, comfortable & finishing can incorporate desirable properties.  Finishing is the heart of textile processing.  Value addition = {(Technology) + (Innovation)} x Quality.
  3. The need for competitive strategy that utilizes;  Chemical compatibility to provide one-shot multifunctional finishes.  Cost reduction through process integration and minimizing the consumption of all utilities.  More environmentally friendly and application method.  Cost reduction through minimization of effluent treatment cost.  Improve process control, monitoring and automation.  Greater innovation in chemical finishes.  Quick response through right-first-time, right-on end time, right-every-time finishing.
  4.  Finishingof textile fabric is carried out to increase attractiveness and/or serviceability of the fabric.  Differentfinishing treatments are available to get various effects, which add value to the basic textile material.  The domestic readymade garment sector is booming, and garment processing has emerged as one of the important production routes towards meeting quick changing demands of the fashion market
  5. METHOD OF APPLICATION: There are two methods of garment finishing.  Dip process.  Tumbling process Dip process: -  Dip the garment inside out in finishing chemical keeping MLR 1:5. Washing machine may be used.  Rotate the garment for 20 min.  Hydro extract the garment to 70 to 80% pick up.  Tumble dry at 70°C to moisture content 10—12 %.  Turn the garment right side out.  Iron/steam press the garment to set the creases at desired places.  Cure at 150—160°C
  6. Tumble method: -  In this process the garment are placed (inside out) into a machine with sealed (not perforated) cylinder and application of recipe by either pumping or spraying.  The drum is turned for 20 min there should not be excessive dripping of chemicals from the garment. If so more tumbling time is allowed.  This method is being used more and more due to the fact that there is no wastage of chemicals.  After saturation the garments are hydro extracted tumble dry at 70°C to 10—20 % pick up moisture content.  The iron and steam press the garments to remove/set creases. Cure at 150—160°C for 8 -10 min.
  7. Important features: -  MLR should not be less than 1: 0.85 for the garment weighing 600 gm and 1:1 for those weighing more than 600 gm.  Minimum time of tumbling should be 20 min.  Tumble rotation speed 20-30 rpm.  Tumble drying temp. Should not be more than 70°C.  Moisture retention after drying should be 10-12%.
  8. Wash down effects It can be achieved by a variety of garment processing techniques which are mainly dependent on physical and on chemical abrasion of the surface dye there by producing different wash down or break-in looks. In garment washing the seams, waistband, pockets, cuffs, etc develop a contour, which can be obtained by washing in garment from only. Washing down of garments is the latest development in fashion technology. Washing brings out special effects changing the feel and look of garments.
  9. Five good reasons can be attributed for washing the garments.  To influence physical properties such as softness, handle, drape or fall , absorbency, creasing etc.  To influence appearance by altering the nature of yarn of fabric or lusture.  To create shrinkage & effects of shrinkage like puckering of garments.  To create abrasion & related effects.  To create a trend in fashion with consistent quality & brand image with range of finishes.
  10. Denim washing It is the aesthetic finish given to the denim fabric to enhance the appeal and to provide strength Indigo jeans were once the only item processed by the garment wash method  Emphasis is on Comfort And Softness. Fashion Trends Favor The Broken-in Look And Worn/Faded seams that can only be achieved through garment processing
  11. DENIM WASHES ARE OF TWO TYPES: 1. Mechanical washes Stone wash  Micro sanding 2. Chemical washes Denim bleaching Enzyme wash Acid wash
  12. Any of these procedures can be modified To fit a particular situation, Depending upon garment type (i.e., heavyweight denim versus lightweight chambray), Available equipment, and Process flow. Also, some of these procedures yield garments suitable for over dyeing, which may create a whole new look.
  13. PROCEDURE 1. Garments can be inverted to minimize unwanted abrasion streaks (especially useful when preset creases are present). 2. Load machine with garments. 3. Desize with alpha amylase enzyme and detergent. 4. Drain. 5. Rinse. 6. Fill machine with water and heat to 60◦C. The liquor ratio can range from 10:1 to 20:1. A number of synthetic detergents can be used. Also, alkaline products such as soda ash or caustic soda can be added in amounts ranging from 0.5 to 2.0 grams/liter. Some chemical suppliers offer special products that accelerate the wash down process, dependent upon the particular dyestuff used. 7. Wash/tumble action for 20-60 minutes, depending upon desired effect. 8. Drain and rinse. 9. Apply softener. 10. Tumble dry. 11. Invert garments, if previously turned. 12. Press, if required .
  14. STONEWASH  In the process of stone washing, freshly dyed jeans are loaded into large washing machines and tumbled with pumice stones  It means Pre washed, abraded, faded either regular or irregular looks are produced by subjecting the dyed garments to severe washing treatments  In order to accelerate the garment wash effect and to give garments an even more unique appearance, desirable look and softer hand, abrasive stones were introduced to the wash bath.
  15.  Variations in composition, hardness, size shape and porosity make these stones multifunctional. The process is quite expensive and requires high capital investment.  Pumice stones give the additional effect of a faded or worn look as it abrades the surface of the jeans like sandpaper, removing some dye particles from the surfaces of the yarn.  A variety of natural and synthetic stones are available for stonewashing with perhaps the most widely used being pumice or volcanic rock.
  16. As the stones are used, they slowly disintegrate, reducing the severity of the stonewash effect over a period of time.  The stones not only abrade the fabric but also gradually abrade the inside of the rotary drum.  A machine used for stonewashing should not be used to dye delicate articles or when abrasion would be detrimental to the fabric.  It’s gives used look because of varying degrees of abrasion in areas such as the waistband, pocket and seems
  17. Degree of colour fading  Garments to stone ratio  Washing time  Size of stone  MLR  Load of garments  Stone weight 0.5-3
  18. Selection of stone  Stone should be selected of the proper hardness, shape, and size for the particular end product.  It should be noted that large, hard stones last longer and may be suited for heavy weight fabrics only.  Smaller, softer stones would be used for light weight fabrics and more delicate items.  STONE WT. /FABRIC WT. = 0.5 TO 3 /1  It depends on the degree of abrasion needed to achieve the desired result.  Stones can be reused until they completely disintegrate or washed down the drain.
  19. PROCEDURE  Load stones into machine.  Load garments into machine (ratio usually 0.5 - 3.0 part weight stones:1 part weight garments).  Desize with alpha amylase enzyme and detergent. Liquor ratio approximately 5-8:1.  Rinse.  Refill and tumble with stones 30 to 90 minutes, depending upon desired effect. Liquor ratio 5-8:1 at 50-70◦C. Scouring additives can also be used.
  20. Drain. Separate garments from stones (garments can be transferred to another machine).  Rinse.  Apply softener (garments can be transferred to another machine for softening).  Extract and unload.  De-stone and tumble dry.  Press, if required.
  21. BACK STAINING OR RE-DEPOSITION:  The dye removed from denim material after the treatment with cellulose or by a conventional washing process may cause "back staining” or "redeposition”.  Re-coloration of blue threads and blue coloration of white threads, resulting in less contrast between blue and white threads.
  22. PROBLEMS CAUSED BY STONES:  Damage to wash machineries and garment due to stone to machine and machine to stone abrasion  Increase in labor to remove dust from finished garments.  Water pollution during disposal of used liquor.  Back staining and re deposition.
  23. REMEDY OF BACK STAINING  Adding dispersion/suspension agent to wash cycle.  Intermediate replacement of wash liquor.  Using alkaline detergent like sodium per borate with optical brightener as after wash
  24. LIMITATIONS OF STONE WASHING:  Quality of the abrasion process is difficult to control outcome of a load of jeans is never uniform, little percentage always getting ruined by too much abrasion.  The process is non-selective.  Metal buttons and rivets on the jeans in the washing machines get abraded.  This reduces quality of the products and life of equipment, and increases production costs.  Stones may turn into powder during the process of making the garment grayish in color and rough too  Provides rougher feel than enzyme wash  Stone may lead the harm to the machine parts
  25. STONEWASH EFFECT:  In traditional washing process, volcanic rocks or pumice stones are added to the garments during washing as abradant. Due to ring dyeing and heavy abrasion fading is more apparent but less uniform.  The degree of colour fading depends on the garment to stone ratio, washing time, size of stones, material to liquor ratio and load of garments.  Normally after desizing, stone wash process starts with pumice stone addition in rotary drum type garment washer.  Process time varies from 60-120 mins.  Stone wash effect is one of the oldest but highly demanded washing effects.
  26.  Stone wash process gives “used” look or “vintage” on the garments, because of varying degree of abrasion in the area such as waistband, pocket, seam and body.  There are many limitations and drawbacks associated with stone washing process, which can be overcome by using new enzyme based washing technology.  This technology also helps to conserve water, time, energy and environment
  27. ENZYME WASH  Cellulase enzymes are natural proteins which are used in denim garment processing to get stone wash look on to the denim garments without using stones or by reducing the use of pumice stone.  Cellulase attacks primarily on the surface of the cellulose fiber, leaving the interior of the fiber as it is, by removing the indigo present in the surface layer of fiber.
  28. Cellulase enzyme is classified into two classes:  Acid Cellulase: It works best in the pH range of 4.5-5.5 and exhibit optimum activity at 50°C.  Neutral cellulase: It works best at pH 6 however its activity is not adversely affected in the range of pH 6-8 and show maximum activity at 55°C.
  29. Neutral Cellulase: These are the enzymes which are active between pH: 6-8  lower abrasion than acid celluloses  low back staining  pH 6 - 8.0 Acid Cellulase:  high abrasion  higher back-staining than neutral cellulases  pH 4.5 - 5.5  optimized pH and temperature = maximum activity of the enzyme
  30. Acid cellulose Recipe and Condition  Cellulose 450 AP (OWG) 0.5 – 1 gm/l  Lube pro VX ( crease inhibitor) 0.5 – 1 gm/l  White MRC (anti-redepositing agent) 1 – 2 gm/l  Treat at 50C and pH – 5 for 30-45 mins Neutral cellulose Recipe and Condition  Americos cellucom 110 OM (OWG) 0.5 – 1 gm/l  Lube pro VX ( crease inhibitor) 0.5 – 1 gm/l  Americos White MRC (anti-redepositing agent) 1 – 2gm/l  Treat at 50C and pH – 5 for 30-45 mins
  31. PROCEDURE Load stones in machine (normally 0.5 - 2.0 part weight stones: 1 part weight garments) if applicable.  Load garments.  Desize with alpha amylase enzyme and detergent.  Rinse. Add cellulase enzyme (amount, pH, temperature, and cycle time dependent upon type of fabric and desired effects; manufacturer's recommendations should be followed).  Adjust pH as recommended.  Tumble 30-90 minutes.
  32.  Drain.  Rinse well (70◦C). Drain. Separate garments from stones if used (garments can be transferred to another machine).  Apply softener.  Extract and unload.  De-stone and tumble dry.  Press, if require
  33. Advantage of enzyme washing  Soft handle and attractive clean appearance is obtained without severe damage to the surface of yarn.  Simple process handling and minimum effluent problem.  Better feel to touch and increased gloss or luster.  Prevents tendency of pilling after relatively short period of wear.  Can be applied on cellulose and its blend.  Due to mild condition of treatment process is less corrosive.  Fancy colour - flenced surface can be obtained without or a partial use of stone.  More reproducible effect can be obtained.  It allows more loading of the garment into machines
  34.  Environmental friendly treatment.  Less damage to seam edges and badges.  Wear and tear of equipment is minimum due to absence of stone.  Use of softener can be avoided or minimised.  Easy handling of floor and severs as messy sludge of stones does not interfere.  Due to absence of stone, labour intensive operation of stone removal is not required.  Homogenous abrasion of the garments.  Puckering effect can also be obtained
  35. ACID WASH  It is done by tumbling the garments with pumice stones presoaked in a solution of sodium hypochlorite (5 to 10%) or potassium permanganate (3 to 6%) for localized bleaching resulting in a non uniform sharp blue/white contrast.  To remove the colour only on the surface of the garment and produces a frosted appearance  In this wash the color contrast of the denim fabric can be enhanced by optical brightening.  The advantage of this process is that it saves water as addition of water is not required.
  36. PROCEDURE:  Soak the stones in solution of sodium hypochlorite (5 to 10%) or potassium permanganate (3 to 6%) for 1-2 hrs  Stones should be drained of excess liquor with help of mesh  Placed stones and garments in machine  Tumble for 30 mins or until desire effects are achieved. Results are dependent up on the dyestuff, fabric, and concentration of chemical, stones, additives, and equipment  In some cases, stones can be used ( resoaking, porosity )  Rinse  Apply softener  Tumble dry  Press, if req.
  37. 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
  38. MICROSANDING There are 3 ways for this technique:  Sandblasting  Machine sanding  Hand sanding or hand brushing
  39. 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.
  40. SAND BLASTING 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.  It is purely mechanical process, not using any chemicals.  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
  41. Advantages :  Pure chemical process  Water free process therefore no need drying  Variety of distresses or abraded looks possible  Any number of designs could be created by special finishes
  42. Wrinkle Free Finish (or) Ant crease Finish (Or) Wash- N- Wear Finish  Cotton fabrics are mainly selected for apparels because of their durability, ability to with stand the rough laundering, good absorption, comfort to wear and ability to take up a wide range of dyestuffs.  The main headache with the cotton fabric is CREASE formation during washing, laundering and in use. It is an undesirable property and hence the crease resistant finish is to be given. It is called as Anti-crease finish or Crease resistant or Crease recovery finish or 'Wash-n- Wear‘ finishes.
  43. Object of Anti-crease finish  Cotton, viscose fabrics form creases during washing, laundering and in use.  To prevent it, the anti-crease finish is given. It is called as Anti-crease finish or Crease resistant or Crease recovery finish or 'Wash-n- Wear' finishes.  As the resins are used, it is also called as 'Resin finishing'. It is a permanent chemical finish.  To keep the fabric flat smooth and free from undesirable creases
  44. Usually cotton, linen, viscose and cuprammonium rayon are finished with resin Depends on 1. Amount and type of resin 2. Amount and type of catalyst 3. Curing conditions 4. Quality of cotton 5. Process preceding finishing and possible damage
  45. MECHANISM OF CREASE FORMATION  Cotton cellulose molecular chain contains OH groups in both amorphous and crystalline region.  When a load is applied on to cotton fabric, the cellulose chain bends and this bending remains permanent since the chains are In-elastic.  The hydrogen bonds form, between the adjacent chains in the crystalline region are broken and new hydrogen bond are formed at the folding points and in amorphous region, which do not allow the chain to return. Hence the creases are formed.
  46. Method to prevent creases The method of minimizing the formation of creases involves cross-linking the OH groups of adjacent cellulosic chains by means of cross-linking agents. The introduction of cross-links imparts dimensional stability and elasticity to the fibrous material an makes it crease resistant and crease recoverable. The most commonly used cross-linking agents are nothing but resins. The resins react with OH groups of cellulose forming cross links which is durable
  47. Advantages of resin finishing  It improves the Crease Resistance and Crease Recovery property  It reduces the shrinkage of fabric during laundering  It improves the resilience, drape and handle  It imparts a smooth and quick drying property  It improves the Dimensional stability and weight  It increase the strength of rayon in both wet and dry states  It gives resistance to degradation by light and laundering  It improves the fastness to light and wash  It prevents the inter-molecular slippage in the fiber  It becomes partially water proof and rot proof.
  48. Disadvantages  It decreases the tensile strength and tearing strength  It decreases the abrasion resistance  It gives harsh and stiff feel  It gives an unpleasant odour  It turns yellow after chlorine bleaching
  49. Resins DMU Di Methylol Urea DMEU Di Methylol Ethylene Urea DMDHEU Di Methylol Di Hydroxy Ethylene Urea TMM Tri Methylol Melamine Recipe For Shirting cloth (Cotton, PIC, PN) DMU/DMDHEU 80 -100 gpl cross-linking resin MgCl2 - 8 - 10 gpl catalyst for cross linking reaction PE emulsion 20 gpl Lubricant Reactive softener 30 gpl softener
  50. Process Padding in two bowl padding mangle with 80% expression at room temperature Drying in stenter with minimum tension at 70 - 80°C Cure at 120°C -150°C for 2-5 min Cross-linking and polymerization takes place Washing and soaping - I-2gpl soap or TRO and 2-4 gpl soda ash at 50 -60°C for 10 min acidity is neutralised Softening and drying - rinsed in water with softener Stentering
  51. LASER TECHNOLOGY  It is a computer controlled process for denim fading.  This technique enables patterns to be created such as lines and/or dots, images, text or even pictures.  It is water free fading of denim.  Being an automatic system, chances of human error are slim.  Also called spray painting in denims.  This technique has relatively high cost