Finishing
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Finishing Finishing is a general term for a magnitude of processes and treatments that a fabric may undergo after it has been made (woven or knitted) and colored (dyed or printed). It is the final processing of the cloth. Its purpose is to make the fabric more suitable for its intended end use. Textile finishes can be classified as aesthetic finishes and functional finishes. They are also categorized as chemical finishes and mechanical finishes.
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Finishing
Aesthetic Finishes
These are finishes which change the appearance, drapability and hand (feel) of fabrics including parchmentizing, softeners, and stiffening finishes. Finishes that alter or create texture include burnout designs, embossing, plissé, raised fiber surfaces (brushing, gigging, napping, sueding, and flocking). Finishes that alter fabric luster include beetling, calendering (simple, glazed, moiré, schreinering), optical finishes (delusterants, and optical brighteners).
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Finishing
Functional Finishes
These are finishes which improve the performance properties of fabrics. Finishes that enhance care properties include durable press, soil-release, stain- and soil-resistant finishes. Finishes that provide comfort and safety include antistatic, chemical-protective, absorbent, flame resistance, water-repellent and waterproof finishes. Finishes that alter durability include abrasionresistant, slip resistant, and shrinkage control. Finishes that provide environmental protection include antimicrobial finishes, fume fading inhibitors, metallic and plastic coatings, and mothproofing.
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Finishing
Aesthetic Finishes
Finishing that Changes Appearance, Drapability and Hand Parchmentizing » A finishing process to give cellulosic fabrics such characteristics as transparency, linen-like hand, and texture. The fabric is immersed briefly in an acid bath under controlled conditions and then quickly neutralized. This finish is most effective on mercerized cotton. Softening » Softening agents are frequently used to improve the hand and drape of fabric. The most commonly used softeners are oils, fats, wax emulsions, soaps and synthetic detergents, and silicone compounds. Silicone compounds produce relatively durable softening. Stiffening » Some fabrics need to be made stiffer and more crisp than they would otherwise be in order to meet an intended end use. Stiffening may be done by any of several chemical finishes, all applied by pad and either dried or cured. Starch is widely used but starch finishes are temporary. Bureau Veritas Consumer Products Services
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Aesthetic Finishes
Finishes that Alter or Create Texture Plissé » This is a permanent finish, produced on cotton by the treatment of sodium hydroxide to produce a puckered or crinkled fabric. Sodium hydroxide is printed on the fabric in the form of paste and the fabric shrinks only where the paste is applied. Acetate, rayon, and manufactured fabrics with a puckered effect can be produced by chemical treatment or heat setting.
Embossing » This is a process to produce a raised design or pattern in relief on fabrics by passing the cloth between hot engraved rollers that press the design into the fabric. In thermoplastic fabrics (polyester, nylon) embossing is permanent. In other fabrics, resin finishes are used to create a durable effect. Bureau Veritas Consumer Products Services
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Aesthetic Finishes
Finishes that Alter or Create Texture Diagram of Embossing Rolls
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Finishing
Aesthetic Finishes
Finishes that Alter or Create Texture Raised Fiber Surface » Fabric surfaces can be raised by brushing, gigging, napping, and sueding. Fabrics must be made of staple-fiber yarns with low twist and lubricated to ease the extraction of fiber ends from the cloth.
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Finishing
Aesthetic Finishes
Finishes that Alter or Create Texture Napping » Napping uses a series of 24-30 cylinders covered with fine metal wires bent into small hooks, to produce a thick, raised fiber surface on fabrics produced from loosely twisted staple-fiber yarns. A fabric can be napped on a single side or both. The nap maybe brushed and/or sheared to make it even. Napping is used on broadcloth, flannel, and blankets Sueding » A process similar to napping, it is a mechanical finish that produces a soft, suede-like surface on the fabric. Instead of rotating, bristled wire covered brushes used in napping, the rotating cylinders used for sueding consist of a sandpaper-like material. Bureau Veritas Consumer Products Services
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Aesthetic Finishes
Finishes that Alter or Create Texture Diagram of Napping Process
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Finishing
Aesthetic Finishes
Finishing that Alter Fabric Luster Calendering » A finishing process producing a flat, glossy, and smooth surface by passing the fabric under pressure between cylinders. The greater the heat and pressure, the higher the luster. Calender finishes include ciré, glazing, moiré, and schreinering. Ciré » Ciré is a highly polished fabric produced by impregnating the fabric with wax or a thermoplastic material and then passing it through friction rollers. The resultant fabric is highly lustrous and takes on a popular wet look. When thermoplastic fiber fabrics are ciré finished, the fabric becomes moderately water repellent due to flattening and partial fusing of fibers.
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Finishing
Aesthetic Finishes
Finishing that Alter Fabric Luster Glazing » A process that produces a smooth, high polish on the surface of the fabric. The material is treated with various materials including starch, paraffin, and shellac. Three rollers are used; the center roll is cotton-padded or paper, and the other two are metal. The metal rolls operate at a very high speed, and the other roll turns more slowly. The polish is created by the friction of the rolls.
Moiré » A moiré finish is characterized by a soft luster and an optical effect, which is created by interference between light rays reflected from the crushed and uncrushed parts of the fabric. Two layers of identical fabric are placed face to face and then subjected to heat and pressure whereby a pattern of parallel lines formed by the weft yarns of each fabric is impressed upon the weft yarns of the opposing fabric .
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Aesthetic Finishes
Finishing that Alter Fabric Luster Schreinering » A finishing process where the fabric is passed under pressure between an engraved steel calender roller and a smooth roller. The engraved roller has 180360 fine lines embossed. This process flattens the fabric and produces fine lines on the surface which increases the light reflection to create a soft silk-like luster.
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Aesthetic Finishes
Finishing Finishing that Alter Fabric Luster
Optical Finishes
Delusterants » A process of dulling the luster of manufactured fibers, yarns, or fabrics with pigments or chemical treatment. In most manufactured fibers, pigment is introduced in the spinning solution to reduce luster. Delusterants such as barium salts, zinc oxide, aluminum oxide and china clay can also be applied to yarns and fabrics.
Optical Brighteners » Optical brighteners are used in finishing to maintain white and bright fabrics. They adhere to the fabric and create an appearance of whiteness or brightness by the way they reflect light; they absorb ultraviolet light and reflect it as visible blue light.
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Finishing
Functional Finishes
Finishing that Enhance Care Properties Durable Press » This finish provides garments with shape retention, durable pleats and pressed creases, durably smooth seams, and wrinkle resistance. » There are two methods: 1) post-cure technique in which the garment rather than the fabric is cured and heat-set after construction or 2) flat or precured technique in which the piece goods are finished and cured. Almost all fabrics for durable press are blends of cellulosic fibers and polyester.
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Functional Finishes
Finishing
Finishing that Enhance Care Properties Soil Release » A finish that increases the absorbency of a fabric, and which makes it easier to remove soil and stains in washing. This finish (1) allows the stain to leave the fabric faster; (2) increases wicking action for greater comfort; (3) makes fabric dry-cleanable; and (4) maintains brightness after repeated laundering.
Stain- and Soil-resistant Finishes » Stain- and soil-resistant finishes resist staining. Stainand soil-resistant finishes reduce the rate of soil deposition on a fabric either by creating an electric charge that repels the soil or by producing a smooth surface to which soil will not adhere. Fabrics treated with such finishes are therefore easily cleaned.
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Functional Finishes
Finishing Finishing that Alter Durability Abrasion-resistant Finish
» Abrasion resistance can be imparted by an acrylic resin; however, some resins are too soft to be effective and some are too hard and introduce brittleness to the fabric. These resins bind the fibers more firmly to the yarns. Some fiber such as nylon have inherent resistance to abrasion. Abrasion-resistant finishes are used on fabrics subject to prolonged abrasive wear such as pockets, waistband lining, and hatbands.
Slip-resistant Finishes » Finishes applied to a fabric to reduce or eliminate yarn slippage and reduce seam fraying are called antislip, slipresistant, or nonslip finishes. Products such as rosins (they have poor washfastness), colloidal dispersions of silica (they reduce surface smoothness but are not durable), and formaldehyde resins (they are durable) are commonly used. Bureau Veritas Consumer Products Services
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Finishing Finishing that Alter Durability
Functional Finishes Shrinkage Control
There are Two Kinds of Fabric Shrinkage: »
Relaxation Shrinkage This occurs because the fibers and yarns are under tension when the fabrics are made. Later when the fabric is wet in a tensionless condition, relaxation occurs.
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Progressive Shrinkage This occurs each time a fabric is laundered. Unlike relaxation shrinkage which occurs only once, progressive shrinkage continues and the fabric shrinks a bit more with each laundering. Of the major fibers, only wool and viscose rayon are subject to progressive shrinkage .
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Shrinkage Control The factors that control shrinkage in fabrics or garments are: Construction: A tighter fabric construction reduces potential shrinkage Yarn twist: Optimum twist (based on yarn size) is very important for controlling shrinkage and torque. Type of Weave or Knit: Pain weave of Jersey knit show more resistance to shrinkage than other types. Tension During Sewing of Garments: Uneven or too much sewing tension can lead to differential shrinkage causing puckering in the seam areas. Stability of Fiber and Yarns: Improper stabilization could lead to excessive shrinkage especially in blends where synthetic fiber shrinks differentially than the cellulosic fibers. Bureau Veritas Consumer Products Services
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Shrinkage Control Illustration of Shrinkage on Woven Fabric Caused by Fiber and Yarn Swelling
Loomstate Fabrics
Fabric After Washing
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Finishing Finishing that Alter Durability
Functional Finishes Shrinkage Control
Compressive Shrinkage (Relaxation Method) » Used for woven cotton, tubular knit cotton, linen and rayon; the method consists of mechanically compressing the fabric lengthwise by overfeeding onto a large roller with damp blankets. Sanforized is a well known trade mark for fabrics treated by this method.
Heat Set (Relaxation Method) » Used for fabrics from thermoplastic fibers such as nylon, polyester and acrylic; it is based on the principle that thermoplastic materials will become stabilized in their configuration in which they happen to be when heated to their softening temperature.
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Finishing Finishing that Alter Durability
Functional Finishes Shrinkage Control
Sponging (Relaxation Method) » Used for woolen and worsted fabrics; it consists of thoroughly wetting the fabric with water or steam and allowing the material to dry slowly in a relaxed tensionless state. This does not make wool washable or shrink-proof; it permits wool to be steam pressed or caught in rain without severe shrinking.
Resin Treatments (Relaxation Method) » Used for fabrics of rayon and cotton; it involves impregnating rayon and cotton with resins and then curing which stabilizes the fabric and thus reduces its tendency to distort. Resins also provide crease resistance. It is preferable to hand wash resin treated rayon fabrics.
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Compressive Shrinkage Illustration of the Felt Blanket Machine Principle
Felt Blanket Principle
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Compressive Shrinkage
Diagram of the Rubber Belt Principle
Rubber Belt Principle
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Shrinkage Control of Knit Fabrics
Belt Principle for Imparting Mechanical Shrinkage for Knits
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Shrinkage Control of Knit Fabrics
Finishing The Micrex Process
For open-width knit fabrics based on cavity type overfeeding
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Finishing
Functional Finishes
Finishing that Provide Comfort and Safety Antistatic » A finish that helps reduce or eliminate static buildup in fabrics. They are chemical compounds that, when applied to a fabric, reduces or eliminates the accumulation of static electricity. This may be added to the fiber lubricant or to yarn during spinning, by spraying, or in a final rinse, or in pad dyeing. Fabric softeners used in home laundering also reduce static.
Chemical-protective Finishes » These are finishes that prevent penetration of herbicide or pesticide through clothing and prevent easy removal by laundering of any pesticide on the surface of clothing. All cotton fabrics are better than polyester because pesticides are absorbed by polyester but not cotton.
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Functional Finishes
Finishing that Provide Comfort and Safety Flame Retardant Finish » For most part, fabrics treated with these finishes burn in the direct path of flame but self-extinguish when the source of flame is removed. » Unfortunately, use of these finishes result in stiffening and loss of fabric drapability, strength loss, loss of finish in laundering (nondurable), and ineffectiveness when laundered in household bleach, soaps, or water softeners. » Some of the commonly used flame-retardant treatments include Pyrovatex CP (for cellulose and its blends), THPC (used extensively for childrens sleepwear), Firestop (trademarked by Cotton Incorporated; used in cellulose and its blends), Fyrol 76, TM-DABT (for 100% cotton and polycotton blends), Proban (cellulose blends), Spartan, Flamegard, Glotard, Fireway, Caliban, and Protogard.
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Functional Finishes
Finishing that Provide Comfort and Safety Water and Stain Repellent Finishes » They are chemical finishes that resist the penetration of water through the fabric but permit the passage of air or moisture. The principle behind this ability is that yarns rather than fabric are coated with repellent chemicals. Water repellent finishes can be non-durable, durable, and renewable.The principle types include wax emulsions, resins (renewable), silicone compounds (durable), and zirconium compounds (non-durable).
Waterproof Finishes » These are finishes that resist wetting and the penetration of water. Waterproof fabrics are generally woven tightly and coated with rubber, plastic (usually vinyl), linseed oil, cellulose esters, or other compounds. Fabrics are non-permeable to air, possess a firm non-drapable hand and are not comfortable as wearing apparel. Bureau Veritas Consumer Products Services
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Functional Finishes
Finishing that Provide Environmental Protection Antimicrobial Finish » They are applied to fabrics to prevent growth of microorganisms. They thereby control the spread of disease and reduce the danger of infection; help to inhibit the development of unpleasant odors from perspiration and other soils; and reduce damage to fabrics from mildewproducing fungi and rot-producing bacteria. These finishes may be durable or renewable. Pacificate and Sanitized are two well known trademarks for this finish.
Fume Fading Inhibitors » Some colors fade, particularly disperse dyes on acetate, caused by exposure to oxides of nitrogen in the atmosphere. Simple alkaline substances such as borax are sometimes used as after-treatments, but they are not permanent.
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Functional Finishes
Finishing that Provide Environmental Protection Metallic and Plastic Coatings » Metallic and plastic coatings are applied to the back of fabrics. Aluminum coatings, modify the warmth and coolness of fabrics, are used for drapery lining. Plastic coatings help reduce the amount of soil that penetrates the fabric and delay the passage of heat through the fabric. One problem with coatings are they may peel or crack off the substrate.
Mothproofing Finish » Moth larvae and carpet beetles are known to attack animal-fiber fabrics. Mothproofing is a chemical that is added to the dyebath during dyeing of wool fabrics. Treated wool fabrics and silk fabrics are less susceptible to damage by moths and other insects. Finishes based on pyrethroids and pyrimidines are among the most successful products used for mothproofing. Bureau Veritas Consumer Products Services
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Nano-Care
The principles of nanotechnology are utilized to create exceptional performance in everyday items: apparel, home furnishings, commercial interiors, industrial fabrics. Nanotechnology provides the ability to work on a nano or submicron scale to create intelligent structures that are stronger and have fundamentally different, performance-enhancing molecular organizations. NANO-CARE® fabric protection imparts a revolutionary, carefree quality to wrinkle resistant fabric that minimizes stains, offers superior liquid repellency and maintains wrinkle resistance. NANOCARE® enhanced fabrics cause water and oil spills to bead up and roll off fabric without penetrating the fibers. Bureau Veritas Consumer Products Services
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Nano-Care
Finishing Key Features Superior Stain, Water, And Oil Repellency Resists Wrinkles Breathable Fabric Preserves Original Hand Easy Care Durable Performance
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