Fgf Assignment 1

A STUDY DONE ON “TEXTILE FINISHES” AS FABRIC AND GARMENT FINISHING ASSIGNMENT-1 SUBMITTED TO: SUBMITTED BY:

MR. MANISH BHARGAV ABHISHEK RAJ (2) ISHITA SINGH (10) KUNAL KASHYAP (11) RICHA JAIN (16) SHIVAM BAJPAI (20) 1|Page

SHRISHTI GUPTA(22) DFT-IV

NATIONAL INSTITUTE OF FASHION TECHNOLOGY, GANDHINAGAR

ACKNOWLEDGMENT Dictionary has failed me when we begin to thank our teacher Mr. Manish Bhargava for his unflinching support and constant guidance which were a big step forward to the completion of this assignment.His sincerity and perseverance has been a constant source of inspiration. We also thank him for his effective tips. We are really thankful to our team members for their full cooperation and support. This study is a fruitful outcome of a good teamwork. We also like to thank the almighty God without whose grace nothing is possible and is ever needed. It was a nice learning experience for all of us. Any suggestions would be willingly accepted and incorporated.

-Abhishek Raj Ishita Singh Kunal Kashyap 2|Page

Richa Jain Shivam Bajpai Shrishti Gupta

INTRODUCTION Textile Finishing is the general term for a multitude of processes and treatments which a fabric may undergo after it has been made (woven or knitted) and coloured (dyed or printed). It is the final processing of the cloth and its purpose is to make the fabric suitable for its intended end use. That may mean. for example, making the fabric shrink proof, softer, stiffer, water repellent, crease resistant or a combination of these properties.

Objects of finishing:  To improve the appearance of the fabric, that is, make it more attractive or lustrous by operations like calendering, optical whitening, etc.  To improve the feel of the fabric by softening, stiffening, etc.  To cover faults in the original fabric.  To increase weight of the cloth. 3|Page

 To improve wearing qualities of cloth by making it shrink resistant, creaseresistant or free from pills and soiling.  To make garments hold their shape and enable them to be worn withoutironing.  To impart special properties to the fabric for specific end uses.  To set the texture of certain fabrics and make others dimensionally stable.  To produce stronger and more durable fabrics.  To produce novelty effects. Finishes take many forms and are selected or applied with the regard to the:  Type of the fiber and yarn  Thread count  Method of fabric construction  Hand, weight, drapability qualities required  Anticipated end use of the fabric or garment Finishes :  Change and alter the fabric  Modify or improve the hand of the fabric  Make fabric attractive and serviceable  Produce a change in behavior or service characteristics  Provide specific characteristics and desired properties  Control instability or shrinkage of the fabric  Provide aesthetic value to fabric 4|Page

 Are used to conceal inferior structure  Are used to stimulate superior quality goods In order to impart the required functional properties to the fiber or fabric, it is customary to subject the material to different types of physical and chemical treatments. For example, wash and wear finish for a cotton fabric is necessary to make it crease-free or wrinkle-free. In a similar way, mercerising, singeing, flame retardant, water repellent, waterproof, antistatic and peach finishing achieve various fabric properties desired by consumers. The use of 100% synthetic textiles has increased considerably since the development of textured yarns made of filaments, and the growing production of knit goods. The use of open weave has enabled production of lighter, breathable, fabrics to ensure better wearing comfort. The properties of plastic-based synthetic fibers, most important among them being polyamide, polyester and polyacrylonitrile, are essentially different from those of natural cellulosic and wool fibers. Hence the sequence of finishing operations is likely to be different. While cellulosic fabrics require a resin finishing treatment to impart easy-care properties, synthetic fibers already exhibit these easy-care criteria and require only a heat setting operation.

AIMS OF TEXTILE FINISHING The final chemical treatments of the fabric which are carried out to impart special characteristics e.g. softening, stiffening, crease resisting, flame retarding, soil release effect etc. is known as textile finishing. The aim of the finishing is to improve the outward appearance and the quality of the fabric, and impart its specific properties. Cycle of Finishing Process The whole cycle of finishing consists of mechanical and chemical processes, which are used depending on the kinds and end uses of the fabric. Mechanical processes include drying, calendaring, schreinering, embossing, sueding, raisingetc and chemical processes include in the application of special 5|Page

substances on the fabric, impregnation with size, starch, dextrin and other polymeric substances. Plain fabrics (bleached, dyed and printed) are subjected to finishing and other kinds of treatment. For instance white printed fabrics with a white ground are passed through a padder containing a solution of optical whitening agents for imparting glassy effect to the fabrics to be printed.

CLASSIFICATION OF FINISHES According to function:  Aesthetic  Functional

According to quality:  Temporary  Semi permanent  Permanent According to the type of machinery:  Chemical  Mechanical

Aesthetic Finishes Aesthetic Finishes modify the appearance and /or handor drape of the fabrics.  Fulling  Mercerization  Napping And Seeding 6|Page

   

Plisse Shearing Softening Stiffening

Functional Finishes Functional Finishes improve the performance properties of the fabric ; like durability, strength etc.         

Antimicrobial/Antiseptic Antistatic Crease resistant Durable Press Flame Resistant Mothproof Shrinkage Control Soil Release Water Proof/ Repellant

Temporary Finishes A finish which is not stable and goes off after the firstwash is known as temporary finish and these finishesdisappears during subsequent washing and usage.

   

Calendering Embossing Starching Softening

Permanent Finishes

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If the finishing effect in the fabric does not disappear and remains unaffected through all the conditions of wear and washing treatments, then the finish is said to be permanent finish.    

Sanforising Resin Finish Water Proof Flame Proof

Semi permanent Finishes A Finishing on the fabric is said to be semi permanent finish if it is stable to more than 5 to 10 washes and not afterwards.  Schreiner Calendering  Buckram Finish

Chemical Finishes Chemical finishes are usually applied to fabric by padding followed by curing and drying. These are also called as wet Finishes.      

Stiff and transparent Flame Retardant Soil Release Water Proof Crease Resistance Softening

Mechanical finishes Mechanical Finishes usually involved specific physical treatment to a fabric surface to cause a change in fabric appearance. This is also known as dry finish.  Calendering  Raising  Sanforising 8|Page

 Milling Aesthetic Finishes The appearance of fabrics is sometimes deceiving. In part, the appearance depends on the type of fibers, the construction of the yarns and fabrics, and the dyeing and printing involved. However, finishes can be applied to fabrics that enhance the basic aesthetic qualities. Aesthetic finishes influence the luster, texture, drapability and surface appearance of fabrics as well as enhance a host of other qualities. Luster, Pattern and Surface Appearance Permenent or temporary changes in surface pattern and luster of fabrics can be achieved through a variety of finishing techniques. Techniques such as calendering, beetling, and burning-out influence the resulting appearance of the fabric.

Calendering is a mechanical process that finishes fabrics by passing them between a series of rollers. By varying the rollers, adding any additional chemical treatment and/or temperature, a variety of calendered finishes result, including: glazed, ciré, embossed, Schreiner and moiré fabrics.

Glazed fabrics such as polished cottons or chintz fabrics are created by saturating the fabric in a starch, wax or resin solution and allowing it to dry before calendering it. 9|Page

Chintz fabric label

Fabric without glazed finish

Fabric with glazed finish

Ciré fabrics with their glossy or wet look are produced in a manner similar to glazing. Ciré fabrics are coated with a wax or resin before being calendered with heated rollers. 10 | P a g e

Fabric without ciréd finish

Fabric with ciréd finish

Embossed fabrics have a pattern imprinted or embossed into the fabric. The embossed pattern is created by passing the fabric between a heated embossing roller and a shaped paper roll.

Embossed fabric, face side 11 | P a g e

Embossed fabric, reverse side Schreiner finishes on fabrics produce soft luster and hand by flattening the yarns and surface of a fabric through calendering.

Fabric without Schreiner finish

Fabric with Schreiner finish

Moiré fabrics have a distinctive water marked look created in the calendering process. Moiré is developed using either a moiré embossing roller or a high compression calendering of two layers of ribbed-base fabric in a single pass. 12 | P a g e

Fabric without moiré finish

Beetled fabrics have a smooth, lusterous linen look. In the beetling process, the yarns of the fabric are flattened as the fabric revolves around a drum while the surface is pounded with hammers.

Burn-out finishes are created by applying chemicals that dissolve, burn-out or shrink parts of a fabric creating distinctive patterns. Acid designs have distinctive transparent and opaque patterns in a single fabric. Acid designs are created by printing a chemical solution in a particular pattern. The acid, or chemical solution, causes the fabric to burn-out and become transparent. The portions of the fabric that didn’t receive the chemical treatment remain opaque. Plissé has distinctive puckered areas. Puckering is the result of the application of chemicals on the base fabric, which causes portions of the fabric to shrink.

Fabric with burnout design

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Fabric with puckered finish

Texture Finishes can alter the surface texture of a fabric. Fabrics can be made smoother or rougher, or given textured patterns through a variety of means. Napping or sueding of fabrics produces a soft, smooth, napped finish. Sueding can be accomplished by sanding the surface of a fabric to roughen the fibers and produce a napped or sueded texture.

Face of fabric with sueded finish

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Reverse of fabric with sueded finish

Shearing is a process that evens out the length of the pile of fabric in a controlled manner. Shearing can be used to create raised patterns or to smooth the overall nap of a fabric.

Terry cloth without sheared finish

Terry cloth with sheared finish

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Some sheared fabrics are also brushed. Fabrics are brushed to remove loose fibers, and in some cases, to direct the nap of the surface in a single direction. Common examples of fabrics with brushed finishes are brushed corduroy and brushed denim.

Denim twill without brushed finish

Denim twill with brushed finish

Plain woven flannel with brushed finish

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Texture can also be developed by adding fibers in the finishing processes. Flocked finishes add texture by adhering short fibers to the surface of a fabric. Flocking can be used to create the appearance of a pile design or allover piles.

Fabric with flocked design Tufted finishes or decorations are created by sewing additional yarns to the surface of a fabric, creating a multi-dimensional appearance.

Face of fabric with tufted finish

Reverse side of fabric with tufted finish 17 | P a g e

Embroidered finishes are machine or hand applied yarns added using satin or fancy stitches to create textured patterns.

Fabric with embroidered design

Drapability and Hand Finishes used to change the luster and texture of fabrics often have affects on the drapability and hand of the fabric. Yet, other finishes have been developed to directly affect the drapability and hand. Depending on the desired use, some finishes are intended to stiffen the fabric while others are intended to soften it.

Fabrics can be stiffened by adding sizing. The starches, gelatin or other resins that make up the sizing give the fabric stiffness and body, allowing the fabric to hold its shape. Crispness or body is given to cottons in a process known as parchmentizing. Parchmentizing uses an acid wash to make cotton almost transparent, and yet permenantly stiff such as in organdy.

Fabric without parchmentized finish 18 | P a g e

Fabric with parchmentized finish

Fabrics can be softened using fabric softeners, enzyme treatments or creping. Fabric softeners coat the surface of the yarns and allow yarns to slide more freely over other yarns, thus giving the fabric a softer feel. Enzyme treatments produce a softer hand and smoother texture by dissolving portions of the cellulosic fibers. Enzyme treatments reduce fuzz on the surface but often weaken the fibers in the process. Creping is accomplished by using a special machine the feeds fabric faster than the fabric is removed, causing a creping or textured effect. Creped fabrics have more stretch and bend more easily, causing them to feel and drape softer.

Fabric with creped finish

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Functional Finish Characteristics 

This type of finishing inhibits the growth of microbes on the surface of the fabric.

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Maintains hygiene and freshness, stops bad odor.



Controls or eliminates microbial staining.

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Improves life of the articles wherever it is applied.

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Improves hand of most of the fabric.

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Eliminates the chances of disease transmission.

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Effective on any substrate like cellulose, synthetics as well as their blends and any surface other than textiles.

Aroma Therapy – Fragma series/ Moisturizers/ Essential oils/ Aloe Vera Microencapsulation of fragrances has been used to maintain a fresh aroma on the textiles. Aromatherapy provides potential benefits to the consumer through promoting a feeling of comfort and well being. Different fragrances are used to stimulate different moods like, Relaxing/encouraging sleep, using fragrances for bedding and nightwear Muscle easing, applied to after sports activity garments Uplifting/ head clearing for active sportswear Clear thinking/confidence building by using fragrance applied to formal business wear.

Today the most popular use of Essential Oils is for aromatherapy. Each oil is attributed with a range of properties that help achieve physical and emotional balance. Aromatherapy includes blends of various fragrances like, Musk, Pineapple, Rose, Lavender, Jasmine, Lemon, Peppermint etc., which are applied on the fabric with the help of a binder. Antistatic Finish 20 | P a g e

Static electricity is created when two non-conducting surfaces, such as synthetic textiles, rub together. The two surfaces become oppositely charged and as the rubbing continues, an electrical charge will build up, increasing in strength (voltage) until it can be discharged by contact or close proximity with a conducting surface such as a metal radiator or door handle. This can be accompanied by a spark, and the wearer can experience the electrical shock, which is unpleasant. Static electricity also causes fabrics to “cling”, when two layers of clothing rub together, causing discomfort. Dry-soiling of clothing: A further problem with static electricity is the collection or pick-up of fine particles of dust or ash by charged textiles. This can lead to unsightly marks on the fabric surface. Anti-static finishes: Although antistatic (metallic or carbon fibre) yarns are available for high-technology fabrics, for apparel use topical anti-static finishes are generally used, but these have a number of faults: they are either soft handling, but non-durable or are durable but with a very harsh handle.

Bio softening of Protein Fibres Wool fabrics, both knitted and woven have a natural tendency to felt and shrink irreversibly. The commercial processes rely on chemical modifications and use chlorine or permono – sulphuric acid to modify the fabric surface. Chlorination results in toxic AOX byproducts and hence it compelled the use of enzymatic treatment for shrink proofing. Protease can markedly reduce the AOX contents in effluents. It is found out that physical and chemical treatments should be combined with enzymatic treatment for shrink resistance of wool, such as peroxidizing wool with Potassium Permanganate and Ammonium Sulphate. Subsequently giving proteolytic treatment results in complete descaled fibres with enhanced softness and luster. High quality wool fibres can also be obtained by the application of heat resistant neutral protease that results in cashmere like feel.

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Protease pretreatment combined with chlorination or oxidative treatment using sodium hypochlorite or Potassium Permanganate and subsequently polymer application reduces the shrinkage area of wool fibre. Cool Finish (snocool) When temperature rises, we tend to sweat. This is a natural reaction of our body to maintain the temperature around 97°F. The sweat when evaporates, takes along with it heat equivalent to heat of evaporation of water, thereby maintaining the temperature of the body. The cool finish technology works in three different ways. The snocool finish uses the moisture management route i.e. it will enhance the natural phenomenon of sweat evaporation. This finish absorbs and dissipates sweat evenly throughout and thus gives a cool feeling to the wearer. Snocool finish when applied to the fabric, reflects light and produces the cooling effect. Moisture management / hydrophilic finish Ever since synthetic fibres became popular for clothing purposes, there has been the desire for a finish to change the hydrophobic character of these fibres. The main reason was to improve the wearing comfort. Hence the necessity to Improve synthetic fibres with regard to their absorbency Areas of textile finishing where improving the absorbency is still one of the main considerations are sportswear, some of which is also made with functional jersey with hydrophobic synthetic fibres on the inside and hydrophilic cellulosic fibres on the outside. The mode of action consists of the finest fibrilled microfibres (PES, PA or PP) transporting the moisture rapidly from the skin through the capillary interstices to the absorbent outer layer. In this way the textile layer of synthetic fibres next to the skin remains dry (below figure)

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Mechanical treatments  Drying  Steaming  Tentering  Sanforizing  Raising  Calendaring/Schereinering/Embossing  Perforating and slitting  Shearing

Chemical Treatments Temporary chemical treatments:  Hardening  Softening with non-fabric reactive finishes Permanent chemical treatments:  Anti-crease finish  Anti stats  Antimicrobials  Lubricants 23 | P a g e

 UV absorbers add polymer stabilizers  Thermoplastic binders, resins and emulsion polymers  Thermosetting resins and crosslinking agents  Softening with reactive polymer  Durable flame retarding  Durable water repelling etc.

Steaming A fabric steamer uses steam rather than heat to remove wrinkles. The steam, and slight pressure of the steamer's surface, relaxes the fibers rather than flattening them. Because of this process, using a fabric steamer is gentler on clothing, faster than using an iron, and eliminates scorching. The fabric steamer is ideal for use on napped fabric, such as velvets and velveteen. A traditional iron will crush the nap, unless used with a needle board, but the fabric steamer doesn't exert pressure, preserving the luxurious look and feel of any material. Even very delicate materials, such as satins and silks, benefit from the gentle care of a fabric steamer. Sanforizing It is a process whereby the fabric is run through a sanforizer; a machine that has drums filled with hot steam. This process is done to control the shrinkage of the fabric.

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Tentering It is the mechanical straightening and dying of the fabric. Tenter fames hold the fabric with special pins. The chain is spread apart to the desired width of the fabric. The fabric is moved through dying units. Later the fabric is rolled on cylinders. Calendaring/Embossing/Crabbing Fabric calendaring is effected in special machines I.e. calendars, the main working organ of which is rolls with smooth surface for normal calendaring engraved surface for emboss calendaring and engraved finer lines for schreinering calendaring or for getting crepe effect. The calendar may be 3 bowl or five bowl and the contacting one bowl is plain steel roller and the other may be covered with rubber otherwise the fabric at nip point will break if both bowls are hard.

Glazing or rolling calendar: This method is not particularly important for nonwoven fabrics, with occasional exceptions. The smooth surface can be obtained usually by selecting an appropriate form of bonding and, especially, for drying a wet-bonded web. Calendaring has not met with much success since it is often accompanied by undesirable compression. The only time a rolling calendar is used is when two steel rollers are paired to break the so-called 'blotches' in spun-bonded fabrics.

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Moiré or goffering calender: The calenders are common in nonwoven finishing and are used in the compacting of the webs made of natural and synthetic fibers. This type of calendering can be considered to be both a bonding and finishing process. Webs composed of longitudinally oriented cotton or viscose fibers with a GSM of about 10-30 g/m2 can be stiffened and compacted sufficiently by passing them through a goffering calender when slightly damp. Hot embossing of synthetic fiber webs, even when the fibers are longitudinally oriented, produces a product remarkably strong due to the fibers melting at the embossed areas. The patterns can be of grid, webbed or point type. The temperature of the heated rollers is generally 20-30°C above the melting point of the fibers and the nip roll pressure 20-50dN/cm, depending on the volume of the web and the proportion of synthetic fibers it contains. If the web is cross-laid, point embossing results in maximum strength. If the fibers are arranged lengthwise, webbed embossing is employed.

The embossing effect is used to obtain special effects such as leather graining, simulated weave, plaster, brush strokes, cord and mock tiling. Another area in which heated calenders used is in the manufacture of laminates. Here thermoplastic fibers, layers of thread or film are placed between two layers of non-plastic web and are fused together by heat and pressure. Such laminates are 26 | P a g e

used as tablecloths, seat and cushion covers. Calenders are also used in the transfer printing of the bonded webs. Crabbing is a preliminary treatment for both un-dyed and dyed woven fabrics with differing objectives. In the case of un-dyed woven material the crabbing process serves to fix the fabric so as to avoid too intensive creasing and felting at the subsequent dyeing stage. After being dyed the woven fabric is smoothed and leveled by crabbing. Silicone blankets are used in this process. Perforating and Slitting The nonwoven bonded fabrics produced are too stiff and are, therefore, unsuitable for clothing. This is because the individual fibers are not free to move in relation to one another, as are threads in woven or knitted fabrics. Perforating and slitting are two methods practiced to improve the fall or drape of nonwoven bonded fabrics. Perforating The Artos method is a method of perforating in which the web, which has been bonded by using chemicals, is perforated with hot needles. This process not only punches holes but also reinforces as a result of cross-linking and condensation of the bonding agent. The Hungarian firm Temaforg uses a similar method to perforate webs made of synthetic fibers to produce nonwoven bonded fabrics which are strong and yet supple enough for use as building and insulation materials. Slitting Slitting originally developed to improve the softness and drape of films was used by the Breveteam Company for interlinings, in particular for adhesive fixable interlinings. The optimum cut length and distance between the slits to get maximum softness and fall without serious reduction of strength can be calculated. The effect of slitting allows greatest flexibility at right angles to the direction of the slit. The slitting is accomplished by a roller with small blades mounted on it, for example, in an off-set arrangement 1.7 mm apart, making slits of a maximum length of 6.5mm. Rotary knives with spreaders can be fitted to the roller, thus making an interrupted cutting edge. Polyethylene or polyamide film shaped by 27 | P a g e

splitting or embossing and stretching by the Xironet and Smith-Nephew methods make good air permeable bonding layers. Anti-crease finish For getting anti crease effect usually melamine formaldehyde, urea formaldehyde and dimethylol dihydroxy ethylene urea (DMDHEU), butane tetra carboxylic acid (BTCA) etc. can be used. At very high temperature, they react with cellulose and give permanent anti crease effect. The following reactions take place between the cellulose macromolecule and DMDHEU The usual method is Padding with DMDHEU and Catalyst -> Drying at (90100) degree C for 5 minutes -> Curing at (140-150) degree C 5-3 minutes

The following recipe can be used: Stabitex FRD/Fixapret CPN (DMDHEU) = 75 g/L Ploy Vinyl acetate = 20 g/L Ammonium sulphate = 10 g/L Or Magnesium Cholride = 10 g/L Sodium perborate = 0.3 g/L The fabric is padded with the above solution and then dried at 100 degree C following curing at 160 degree C for 3 minutes. Curing can be carried out in the stentering machine or curing chamber. Antistats Static electricity tends to build up in nonwovens made of synthetic fibers due to their lack of moisture regain and conductivity. This can cause problems such as clinging and dragging during processing, apparel that clings and crackles, dangerous discharge of static electricity in explosive atmospheres and tendency to attract airborne dirt and soil in processing and use. The antistats work in three basic ways. They improve the conductivity of the fibers, coat the fiber with a thin layer of material that will attract a thin layer of moisture, and finish the fabric such that it holds a charge opposite to that normally accumulated on the fiber to neutralize the static charge. Antistats can be either durable or non28 | P a g e

durable. Examples of durable antistats include vapor deposited metals, conductive carbon or metallic particles applied by binders, polyamines, polyethoxylated amine and ammonium salts and carboxylic salts. Non-durable antistats usually consist of inorganic or organic salts or hygroscopic organic materials. Examples are quaternary ammonium salts, imidazoles and fatty amides which are cationic. Anionic antistats include phosphates, phosphate esters, sulfonates, sulfates and phosphonates. Examples of nonionic antistats include glycols, ethoxylated fatty acids, ethoxylated fatty alcohols and sorbitan fatty acid esters. Antimicrobials These are used to control populations of bacteria, fungi, algae and viruses on the substrate. The treatment usually prevents the biological degradation of the product or prevents the growth of undesirable organisms. Broadly classed, the antimicrobials are either fixed or leachable. The fixed treatments are durable, but the leachable treatments may transfer to the surrounding environment through migration, solubility or abrasion. A generic list of the treatments include alcohols such as isopropanol or propylene glycol, halogens such as chlorine, hypochlorite, iodine, N-chloramine and hexachlorophene, metals such as silver nitrate, mercuric chloride and tin chloride, various peroxides, phenols quaternary ammonium compounds, pine oil derivatives, aldehydes and phosphoric acid esters. Care should be taken in the application of these compounds to prevent inactivation, loss of durability or masking of the active ingredient with other finishes. Lubricants Lubricants or slip agents are generally applied as processing aids to help in stretching or to improve the process ability of nonwovens. They are also applied to aid in sewing, quilting, tufting or other processes where needles penetrate the fabric. Lubricants impart the same properties as softeners but specifically reduce fiber friction. Common chemicals include sulphonated oils, oil emulsions, silicones, esters, polyethylene dispersions and fatty acid soaps. Many surfactants may also be used. Care should be taken to avoid excessive strength loss. UV absorbers and polymer stabilizers

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Ultraviolet light can do great damage to the polymers causing photodegradation, yellowing, loss in strength and fading of the colors. The damage is generally due to the formation of destructive free radicals in the polymer. The finish can protect the fabric by shielding the fiber or absorbing the light or by chemically quenching the free radicals. The three main classes of products used are, substituted benzotriazoles, benzophenones which are UV absorbers, and hindered amines which are free radical reactants. They are applied from a bath or added to the polymer. Thermoplastic binders, resins and emulsion polymers Binders and resins are widely used in the finishing of nonwovens to add strength, control stiffness, add mold ability or pleat ability, provide durable flame retardants, color, reduce linting and control shrinkage. They soften when exposed to heat and return to their original state when cooled and, hence, can be set. Emulsion polymers are also called latexes. The common binders, resins and polymers include acrylics, PVC, poly-acrylic acid, urethanes, starch, vinyl acetate etc. Thermosetting resins and cross linking agents These are used to produce wrinkle resistant or permanent-press textiles. They are used to crosslink cellulose for wrinkle resistance, crosslink binders for wash durability and solvent resistance. The technology is based on the ability of formaldehyde to react with cellulose and nitrogen containing resins. The important resin types are melamine-formaldehyde, urea formaldehyde and dimethyloethylene urea. The reaction is usually catalyzed by acids, such as Lowry-Bronsted or Lewis acids. Problems encountered include formaldehyde generation, tensile loss, discoloration and amine odor. Softening To impart softness, smoothness and flexibility it is necessary to apply a softening agent. According to ionic nature softener can be classified into:  Anionic softener  Cationic softener  Amphoteric softener  Non ionic softener 30 | P a g e

Among them, cationic softeners are mostly used because most of the textile is anionic in nature. Therefore cationic softeners have a god affinity towards textile fibers. To impart hard or stiff handle it is necessary to apply a softening agent .For stiffening treatment the following chamber chemicals can be used. •

Starch or modified starch

•

Polyvinyl acetate(PVA)

•

Polyethylene Emulsion

Commonly used Finishing methods on Fabrics  Pre –Shrinking Finish: Pre-shirking is needed almost on all fabrics because most textile materials shrink when washed.  Softening Finish: Fabric softening is generally done together with desizing (desize means to destarch) and pre-shrinking.  Brush and Sanding Finish: In many cases we may finish the fabric by brushing or sanding to give them smooth velvet–like or suedelike surface.  Mercerizing and Singeing Finish: Singeing and mercerizing are in many cases related and done at the same time. Singeing is passing the fabric through a flame (fire) so that the hair and nubs of the fabric are burnt off to give it a clean surface.  Resin Finish: Resin finish is to stabilize the fiber to make it shrinkage and crease resistant.  Permanent Press Finish: Permanent Press Finish (P.P.Finish) is generally done on TC fabrics;  Skewing Finish: Skewing is an operation done by machine to make the weft threads in the fabric skewed against the perpendicular warp threads.

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 Chintz Finish: Chintz finish is usually applied on TC CVC or cotton poplin to give it a glossy finish.  Water Repellent Finish: Water repellant finish is different from water proof finish. It means water, if showered on the fabric briefly, cannot make the fabric wet. 

Water Proof Finish

 Peach Skin Finish: Peach skin is a smooth finish applied to finely woven Micro Fiber fabric.  Soil Release Finish: Repel the stains and soil using repellants such as flourochemicals or create a surface that aids the removal of soils when cleaning or laundering using chemicals based on poly-acrylic acid.  Fire Retardant Finish: The finishing of fabrics with flame retardants can reduce the tendency to burn or reduce the tendency to propagate the flame.  Sanforization Finish: Shrinkage in garments is very important issue because when they shrink out of size, they cannot be worn.

Pre-Shrinking Finish on Fabrics Pre-shirking is needed almost on all fabrics because most textile materials shrink when washed. However preshrinking can only reduce the residual shrinkage to a lower percentage, but cannot completely eliminate it. On cotton fabrics, usually take away 8-10%shrinkage by preshrinking, leaving about 5-6% in them.

Preshrinking can reduce only the residual shrinkage This is a generalized form of opinion which clearly indicates that without proper shrinking, these fabrics truly cannot be used to make garments. In fact preshrinking can only reduce the residual shrinkage to a lower percentage, but

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cannot completely eliminate it. Following are the measures one must take about the balance of residual shrinkage:  On cotton fabrics, we can usually take away 8-10 %shrinkage by preshrinking, leaving about 5 - 6% in them. If you really do a good job on shrinking, you may bring it down to 4% which is generally accepted in the trade.  On rayon fabrics we should know by normal preshrinking process alone it is difficult to bring the shrinkage down to 4-5 %as by nature, rayon fabrics tend to shrink each time you wash them in the first several washing. That is why people use the method of resin finish to try to control the shrinkage, or use Dry clean only on the care label to avoid the big shrinkage caused by washing. However both of these methods are not satisfactory because of the following  When you apply resin to the fabric to stabilize the fiber, you may achieve better residual shrinkage, but the fabric will be less dray (not as soft). Besides the resin may be washed away slowly in a few washing and then the fabric will start to shrink again.  When you see dry clean only on the care label consumers may not buy the garments as it is too expensive to dry clean by a commercial laundry.  However of late a beater method has been worked out to pre-shrink the fabric starting from desiring and bleaching. As a result after dyeing or printing, we can use the normal pre-shrinking process to control the residual shrinkage to be about 5-6 % which should be the acceptable level.  Therefore, when we order rayon fabrics, it is important that we discuss the possible shrinkage problem with the mill to make sure he knows what to do to control the shrinkage.

Shrinkage on various Textile Material groups Ramie and Ramie/cotton blend: 33 | P a g e

Shrinkage on 100% Ramie and Ramie/cotton blend is mild and controllable. Normal preshrinking can bring the shrinkage down to 3-5 % which is an acceptable level. Wool and Wool Blend Wool is generally not suitable for washing particularly in hot water. If you wash it in hot water, it may shrink up to 30% depending on the construction of the fabric. If wool is mixed with some other fibers, the shrinkage may improve. Therefore, for wool fabric or fabric with wool content, you should consider the following:  For 100% wool or wool as major content, you should use dry clean only in your care label.  On polyester/wool or acrylic wool, usually washable in cool water. The care instructions should be worded similar to the following:  Machine wash cold tumble dry low.  Remove while it is still damp.  Use line dry or lay flat to dry.  Dry cleaning recommended. From the above, you will see that because there is wool in the fabric, a lot of consideration has been given to the wool content in order not to make the wool content shrink excessively. Other textile materials We should be very careful of the shrinkage of leather. Leather shrinks tremendously if washed and dried by heat. When leather is used in garments, as trim or even as a patch, you must not wash the garment and dry it in tumble dryer till it is 100% dry. If you do the leather part will shrink out of size and become thick and stiff. You must wash it in normal way, but dry it up to 80% and air dry the balance 20% without heat. Sanforization Shrinkage in garments is very important issue because when they shrink out of size, they cannot be worn. Before pre-washed garments became popular, the 34 | P a g e

shrinkage problem was even a bigger one. To tackle the shrinkage problem, a process to pre-shrink fabrics before making garments was invented by an American, Stanford L.Cluett. He registered a trademark "SANFORIZED" to signify that the fabric used in garment has gone through a registered process and the garment is shrinkage controlled (Residual shrinkage about 1%). He advertised the trademark "SANFORIZED" to build up the demand from the consumer level for "Sanforized" garments so that the textile mills and garment makers want to use the Sanforize process and the trademark "sanforized" on the garment label to make the merchandise more appealing to consumers. Of course a royalty has to be paid to the Sanforize Company for the use of the trademark. The above is the brief history of the Sanforized trademark which is internationally known and is still used in the garment industry. However, now days you do not see this name too often on the garment labels, because most garments are now pre-washed where shrinkage problems do not exist. Resin Finish Resin finish is to stabilize the fiber to make it shrinkage and crease resistant. We usually consider applying resin finish on 100% cotton fabrics (mostly knits) or 100%rayon woven fabrics because shrinkage of these 2 kinds of fabrics is hard to control, and therefore we consider to resort to resin finish. Resin finish is not too popular now days because the resin applied will eventually be washed off. Garment buyers therefore, rather use garment wash to get rid of the shrinkage and at the same time get a washed look on the garment which is desirable. Fabric Finishes for Enhancing Appearance There are finishes applied to fabrics to enhance the look and feel of the fabric, in other ways the finishes neither strengthen the quality of the fabric nor they are done to transform the fabric for special purposes such as the fire retardant finish. Softening finish Fabric softening is generally done together with desizing (desize means to destarch) and pre-shrinking. When de-starching is done softener is added to make the fabric soft and smooth. This process is indispensable for the fabric to be used to make garments without pre-washing. Whenever too much softener is 35 | P a g e

used to finish the fabric, the stability of the color may be weakened resulting in lower color crocking standards. Brush and Sanding Finish In many cases we may finish the fabric by brushing or sanding to give them to smooth velvet –like or suede-like surface. The difference between brushing and sanding is: Brushing – the hair is long and the fabric is fluffy Sanding – short hair feels like suede For better results we should handle brushing in the following manner:  For solid color fabrics we should brush first and then dye and brush them one more time. If we dye them first and then brush you will get a frosted effect (with a cast of white color mixed in the solid color) because the fiber in the center of the yarn where the dye could not fully penetrate into may come to the surface o make the fabric to look frosted.  For printed fabrics , we should brush first and then print because of the following reasons: • If you print first and then brush, the printed area may not become as haired or fluffy as the white area or the un-printed area because the dye (particularly pigment dye) covers the fabric like a shield and keeps the fiber down. •

If the fabric is printed with reactive dye making the printed area almost as soft as the un-printed area, then the above phenomenon may not appear, but the colored hair or fiber form the printed area may overlap the un-printed side distorting or spoiling the printed design. If you brush first and then print, the above problem will not emerge.

Mercerizing and Singeing Finish Singeing and mercerizing are in many cases related and done at the same time. Singeing is passing the fabric through a flame (fire) so that the hair and nubs of 36 | P a g e

the fabric are burnt off to give it a clean surface. This is commonly done on most cotton fabrics including denim. It consists of the burning of fuzz on the fabric surface. Before singing the cloth is brushed to remove the loose fabric and also to remove the dust. The fabric is kept flat under tension and passed rapidly over an open gas flame. Later it is passed into a water to cool down. Mercerizing means a treatment by soaking the fabric into caustic soda to give a shine to it. This process is not done on denim because it will hurt the color of indigo or sulphur. However it is mostly done on grey goods or dyeing or dyed goods which has a colorfast quality. Chintz Finish Chintz finish is usually applied on TC CVC or cotton poplin to give it a glossy finish. Sometimes we call it oil finish. This is strictly a fashion. Peach Skin Finish Peach skin is a smooth finish applied to finely woven Micro Fiber fabric. The soft, suede finish are the results of sanding or chemical treatment of the fabric. This finish allows suits and dresses to flow with movement and drape beautifully. The feel of peach skin is soft, smooth and moderately wrinkleresistant. It is a medium weight fabric that has fuzzy, suede like feel. Special Textile Finishes Special finishes are done on textile materials to enable it to use for special purposes such as the finishing of fabrics with flame retardants can reduce the tendency to burn or reduce the tendency to propagate the flame. Laminating is the permanent jointing of two or more prefabricated fabrics. Fire Retardant Finish The finishing of fabrics with flame retardants can reduce the tendency to burn or reduce the tendency to propagate the flame. The flame retardants may char the fuel, quench the reaction of combustion, absorb heat or emit cooling gases or replace oxygen. Flame retardants are durable or nondurable. Durable retardants include decabromodiphenyl oxide, antimony oxide, phosphates, brominated esters, PVC and other chlorinated binders. Nondurables include borates, boric acids, zinc borate, sulfuric acid sulfa mates, ammonium phosphates, urea, etc. Hydrated alumina and zinc borate act as smoke 37 | P a g e

suppressants. Problems in the application include odor, yellowing, loss of tensile strength, stiffening, skin irritation and color change or loss. Soil Release Finish The soil release chemicals reduce the problem of soiling in two ways: repel the stains and soil using repellants such as flourochemicals or create a surface that aids the removal of soils when cleaning or laundering using chemicals based on poly-acrylic acid. Flocking Flocking is a process of making a two-dimensional fabric have a third dimension. It is done by mechanically or commonly electrostatically. Depending on how the adhesive is applied, the whole surface can be flocked or patterns can be made. The adhesives are just like what are used in laminating and include polyvinylchloride plastisols, polyurethane bicomponent adhesives and all kinds of aqueous dispersion adhesives. Laminating Laminating is the permanent jointing of two or more prefabricated fabrics. Unless one or other of the fabrics develops adhesive properties in certain conditions, an additional medium is necessary to secure bonding. Wet laminating Adhesives used in the wet process are dissolved or dispersed in a suitable solvent. The simplest form of wet laminating consists of applying the adhesive to one of the lengths of material that is to be joined, and to put the second length on it with the required amount of pressure.Then drying, hardening or condensing the material that has been joined together is carried out. The solvents can be macromolecular natural or synthetic substances and water. Dry laminating All Kinds of thermoplastics are used for dry laminating. These include powders, plastisols, or melt adhesives, and are applied to the substrates that are to be joined together using suitable machinery. Dry laminated non-woven fabrics have a soft feel. Coating 38 | P a g e

Coating is a basic and exceptionally important form of finishing for non-woven bonded fabrics. The way in which the coating is carried out depends on the substrate, the machinery available, the substance that is to be applied and, also on the effect desired. Slop Padding It is one of the best known methods of direct coating. The coating is put on with a rotary roller, the surface of which is covered in the substance to be applied. The slop padding roller is fed directly with the laminating float by being dipped into it or using special feed rollers. Water Proof and Water Repellent Finishes Fabrics to be used as raincoats, umbrellas, and tarpaulins have to be treated with chemicals to give them a property which makes them water resistant. The finish is called waterproofing and it is a durable finish. Water repellant finish is different from water proof finish. It means water, if showered on the fabric briefly, cannot make the fabric wet.

Water Proof Finish Water proof finish should still be classified by degree because of its involvement in a big duty rate difference for export to the United States.Please note the following: If the fabric in question is a TC fabric and the water proof finish is only a regular water proof finish which cannot pass the Rain water Test No. AATCC35 the import duty is 34% for jackets. However, if the same fabric with water proof finishes which can pass AATCC-35 test and qualifies as rainwater resistant, then the duty is 7.6%. To pass the rain water test no. AATCC-35 the fabric has to go through a Cup Test where the fabric has to stand 600mm water pressure without leakage.(The laboratory can do the test for you)

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Most fabric finishing mills know about the above test and the required water proof standard to qualify for rainwater duty. The importance is to specify clearly what you need when you order the fabric. From the above you will see that the duty difference between 7.6% and 34 % is big. If you use the right quality of water proof finish, you can benefit from the low duty rate. However please note that apart from the water proof finish, the style of the jacket has to be taken into consideration too. If the styling of the jacket is obviously not to be used, and cannot be used as a rainwear, the U.S Customs may refuse to let you enter the garments as rainwear duty, although the fabric meets the water proof standards required. The styling which may cause the jacket not to be a rainwear can be briefly noted an s follows:  Quilting stitches are done on the outside; water can easily go to the padding through the numerous needle holes.  With packets without flaps, water can easily go into the pockets as many pieces joined together. Water can go through the seams. Water Repellent Finish Water repellant finish is different from water proof finish. It means water, if showered on the fabric briefly, cannot make the fabric wet. However, water can still get through the fabric if we continue to shower on it. You can do a test to find out if the fabric has water repellent finish(W.R) or water proof finish(W.P)be has no finish (plain finish) on it as follows:  Put the fabric on a flat surface and put a few drops of water on it.  If the water rolls on it, it tells you this side of the fabric has W.R.Now you use your finger to rub on the water. If it does not get through to the other side, it means this fabric also has W.P on the other side, however if it gets through to the other side it means it has W.R on this side only.  If the water gets absorbed and it got through to the other side easily (Completely wet), it means the fabric has “plain finish” not W.R and not W.P.

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 If the water does not roll, but sticks to the fabric and when you rub on it, it does not go through; it tells you that this side of fabric has W.P finish. Very possibly, it has W.R on the other side, because normally, when the fabric has W.P on the other side. It has W.R on the other side. To make sure what you think is correct, you can turn it over and put water on it to see if the water rolls.  Another test: If you can breathe through the fabric, it is not W.P. If you cannot breathe through the fabric it is W.P

FELTING OF WOOL Felt is matted wool. Wool becomes felt when it is subjected to moisture, heat, and pressure. (In fact, if domestic sheep were not shorn, over time their wool would felt or "cot".) Hot soapy water makes the wool slippery, and causes tiny scales on the fiber to "open up". The scales prevent the fibers from backing up again after they slide across each other; with agitation, the fibers get hopelessly tangled together. When cooled and dried, the scales close and lock the wool into the tough, durable material we call felt. Wetting the Wool Squirt a small amount of liquid detergent over the top layer of wool. Then gently pour about a half cup of HOT water over the wool.

Pressing Down the Wool Press straight onto the wool pile so that the wool compresses into a mass on the bottom of the pan. Add more hot water until all of the wool is wet. Work around the edges, pressing down until all of the wool is matted down.

Working the Wool 41 | P a g e

Hold the pan in one hand, while you gently massage the edge of the wool with the fingertips of the other hand. Use your palm to gently agitate the center. Slowly rotate the pan as you work. Keep rolling the edge of the wool slightly inwards to give it a smooth, finished shape. The soap will squish up between your fingers and the wool will matt together. After about 5 minutes the wool will begin to firm up, and you can begin to work with a more vigorous circular motion.

Turning the Felt After about 10 minutes, the felt will hold together well enough to turn it over. Tip the pan and gently flop the wool out into your hand and place it upside down in the pan. Add more soap or hot water if necessary, and continue working the wool as before.

Rinsing Run warm water into the pan and pour off the soapy water. Then run cold water over the wool and press the water out of it. It should be round, about an eighth of an inch thick, and a little smaller than the pan. It should be felt! If you continue working it, it will grow thicker and smaller. Its not that you are losing wool, its that you are losing air spaces.

Fulling the Felt (You don't have to do this part) If you want the felt to be strong, continue working the felt by running more hot water over it, and rolling and squeezing it in your hands. The more you do this, the "fuller" (thicker and stronger) it becomes. Pressing and Drying 42 | P a g e

When you're finished felting one may want to use an iron (set at "wool") to speed up the drying and flatten it out nicely.

MILLING OF WOOL PROCEDURE Three pieces of fabric will be required, one piece that has been shrink-resisted and two pieces from a fabric that has not had a shrink-resist treatment. Cut the fabric into 5g patterns and mark out for shrinkage testing by placing datum marks on the fabric as illustrated.

Marking of the fabric for shrinkage testing. 43 | P a g e

Sew the edges of the fabric using an overlocker sewing machine to prevent fraying. Fabrics of wool and related animal fibres will shrink when subjected to alternate compression and relaxation in aqueous medium. This contraction which is known as milling or felting shrinkage is due to the migration of the fibres, their unique scale structure and elasticity. A loosely constructed knitted fabric may lose up to 50% of its area during milling. Determination of milling shrinkage. Warm the soap solution to 30°C and maintain at this temperature throughout the milling. Immerse the fabrics to be milled into the soap solution for 5 minutes to thoroughly wet out. Remove from the soap solution and lay flat on the bench and measure, with a steel ruler, the distance between the datum marks to obtain a value for the initial area. If the length between the three pairs of marks is I1, I2, & I3 cm and the breadth b1, b2 & b3 cm, Initial area = I1+I2+I3 X b1+b2+b3 cm2 33 Hand mill the samples in the soap solution for four minutes and again measure. Percentage area shrinkage = (Initial area - final area) X 100 Initial area Repeat the hand milling for further periods of 4 minutes and measure again until the control (untreated) pattern shrinks 30 – 40% or a terminal value is obtained. Tabulate the results and plot a graph of time of milling verses percentage area shrinkage for each pattern. Mill only one untreated and the treated sample. The un-milled sample is retained as a reference. . Wash thoroughly with water to remove soap, dry. Comment on the feel and handle of the milled samples compared to the fabric that has not been milled. Mount all the samples and prepare the graphs and comment on the results.

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CONCLUSION Thus we conclude that the standard textile finishes are of the following types namely:

Quality Oriented       

Calendering Decantising Desizing for woven fabrics. Pressing Scouring with detergents, alkaline solutions, or enzymes removes foreign matter. Shrinking, Sanforization Shearing or singeing smooths the fabric by removing the fine protruding fibers on the surface of the fabric. Flame singeing is the standard process: the wet fabric is passed through an array of gas burners at a suitable distance to burn the pills off of its surface.

Design-oriented

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   

Bleaching of woven fabrics removes any prior color in order to obtain a uniform color during the dying process. Dyeing adds color. Printing adds color and pattern. Watering adds moiré patterns.

Handle-oriented   

Fulling or waulking adds weight and density. Hydrophobic finishing produces a fabric that repels stains or water. Weighting silk with metallic salts or polymer adds weight and improves handle.

Special finishes for natural fibers Bio-polishing removes the protruding fibers of a fabric through the action of an enzyme. Enzymes, such as cellulase for cotton, selectively remove protruding fibers. These enzymes may be deactivated by an increase in temperature. Mercerisation makes woven cotton fabric stronger, more lustrous, to have better dye affinity, and to be less abrasive. Raising lifts the surface fibers to improve the softness and warmth, as in flannelette. Peach Finish subjects the fabric (either cotton or its synthetic blends) to emery wheels, making the surface velvet-like. This is a special finish used mostly in garments. Fulling or waulking adds weight and density and decatising to bring dimension stability to woolen fabrics. Crease-Resist finish or "wash-and-wear" or "wrinkle-free" finishes are achieved by the addition of a chemical resin finish that makes the fiber take on a quality similar to that of synthetic fibers. Anti-microbial finish causes a fabric to inhibit the growth of microbes. The humid and warm environment found in textile fibers encourages the growth of the microbes. Infestation by microbes can cause cross-infection by pathogens and the development of odor where the fabric is worn next to skin. In addition, stains and loss of fiber quality of textile substrates can also take 46 | P a g e

place. With an aim to protect the skin of the wearer and the textile substrate itself, an anti-microbial finish is applied to textile materials. Special finishes for synthetic fibers Heat-setting of synthetic fabrics eliminates the internal tensions within the fiber, generated during manufacturing, and the new state can be fixed by rapid cooling. This heat setting fixes the fabrics in the relaxed state, and thus avoids subsequent shrinkage or creasing of the fabric. Presetting of goods makes it possible to use higher temperature for setting without considering the sublimation properties of dyes and also has a favorable effect on dyeing behavior and the running properties of the fabric. On the other hand, postsetting can be combined with some other operations such as Thermasol dyeing or optical brightening of polyester. Post-setting as a final finish is useful to achieve high dimensional stability, along with desired handle. Stiffening and filling process: A stiffening effect is desirable in certain polyamides and polyester materials (e.g. petticoats, collar inner linings), which can be done by reducing the mutual independence of structural elements of fabric by polymer deposition on coating as a fine film. Hydrophilic finishes compensate for lower moisture and water absorption capacity in synthetic fiber materials, which become uncomfortable in contact with skin. Certain products, based on modified (oxy-ethylated) polyamides, make the fabric more pleasant by reducing the cohesion of water so that it spreads over a larger area and thus evaporates more readily. Anti-pilling finish alleviates pilling, an unpleasant phenomenon associated with spun yarn fabrics, especially when they contain synthetics. Synthetic fibers are more readily brought to the surface of a fabric due to their smooth surface and circular cross-section, and due to their higher tensile strength and abrasion resistance. With knit "picking" also occurs: by abrasion, individual fibers work themselves out of yarn loops onto the surface, and the garment catches on a pointed or rough object. Knitting is susceptible to these effects due to the open weave and bulky yarn. Anti-static finish prevents dust from clinging to the fabric. Anti-static effective chemicals are largely chemically inert and require Thermasol or heat treatment for fixing on polyester fabrics. Polyether agents have been found to be useful but should not effect the dye-equilibrium on fiber, lest they impair the rubbing fastness.In general, Thermasol anti-static agents also have a good soil release action, which is as permanent as the anti-static effect. Anti-static finishes may also be of polyamide type, being curable at moderate temperatures.

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Non-slip finishes give the filaments a rougher surface. Synthetic warp and weft threads in loosely-woven fabrics are particularly prone to slip because of their surface smoothness when the structure of fabric is disturbed and appearance is no loner attractive. Silica gel dispersions or silicic acid colloidal solutions are used in combination with latex polymer or acrylates dispersions to get more permanent effect, along with simultaneous improvement in resistance to pilling or snagging. These polymer finishes are also capable of imparting a soft and smooth handle to synthetic fabric without making it water repellent. Fire Resistant or Flame Retardant finish: to reduce flammability. Anti-microbial finish: with the increasing use of synthetic fibers for carpets and other materials in public places, anti-microbial finishes have gained importance. Products which are commonly applied are brominated phenols, quaternary ammonium compounds, organo-silver and tin compounds, which can be applied as solutions or dispersions.

BIBILIOGRAPHY WEBSITES REFERRED 

www.wikipedia.com



www.scribd.com



www.textileschool

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www.mytextilenotes.blogspot.in

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www.thesmarttime.com



www.fibre2fashion.com

BOOKS REFERRED J.T. Marsh 48 | P a g e

Tortora and Collier Corbman Sello and Lewin

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BIBLIOGRAPHY

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