Chapter 24: Physical and Mechanical Finishes• Aesthetic Finishes- affects APPEARANCE or hand of the textile.• Functional Finishes- Affects PREFORMANCE of textileso Often not visibleo May be topical (only on the surface) OR absorbedo Examples: Wrinkle resistance, fire resistance, water proofing, antistatic• Classification of finishes:o Permanent: lasts lifetime of producto Durability: usually have certain lifespan and involve resin (chemicals) or mechanical treatmentso Temporary: removed after 1-2 launders• Fibers that can be heat set permanently:o Syntheticso Many thermoplastic fibers may be stabilized through heat settings• Through enzyme treatment, durable finishes can be applied to a natural fibero Enzyme treatment- cellulose enzymes are used in finishing cotton, rayon, and lyocell to produce smoother surfaces, a softer hand, and lower pilling. PROCESS: the enzymes degrade cellulosic fibers on the surface of the fabric, and mechanical action removes the weakened fibers from the surface1• Finishes that can be applied at home by consumer:o Hand builders- make fabric feel thicker, stiffer, crispero Fabric softeners- coats yarns to allow some slippage, feel softer• Calendaringo A mechanical finisho Passes fabric between series of two or more rollerso Purpose: smooth fabric or create interesting surface effects• Types of calendaringo Schreinering Produces fabrics with soft luster and soft hand One of the calendaring rolls embossed (imprinted) with 250 fine diagonal liners per inch Flattens yarns Examples: damask, cotton sateeno Friction Calendaring (Glazing) Fabric saturated with starch or resin (chemicals) Dried slightly Fed into machine with rapid moving, heated roller Polishes fabric2 Examples of fabric: Chintz or polished cotton (natural cellulosic fiber)o Embossing calendaring Embossed effects:• if a calendar roller has a raised or lowered design engraved on it Pressing a pattern onto fabrics PERMANENT when applied to thermoplastic fibers DURABLE when applied to fabrics with resin treatment TEMPORARY on other fabricso How fabric is Cired and what it is: Cired- the “wet look”  High surface polish Effects on natural fibers or rayon are produced with waxes and thermoplastic resins. Heat sensitive synthetics are given a permanent wet look when the thermoplastic fibers FUSE slightly under the HEAT of the rollers.o Fabrics can be polished by glazing, or cire’ing.o Moiré Also know as “wooden grain” for its wooden appearance. Technique mostly applied to RIBBED fabrics (fabrics with unbalanced weaves with many small yarns crossing over fewer large yarns)3• Taffeta (medium weight weave from filament yarn used for evening wear)• Faille (prominent rib with fine filament yarn warp and heavy spun yarn filling) Two lengths of same fabric placed face to face with one slightly off grain Enormous pressure by smooth moiré rollerso Embossing can be made permanent when applied to thermoplastic fiberso Brushing Fabrics made from staple fibers may be brushed to remove loose fiber from fabric surface• Brushed denim• Brushed tricot Many napped and pile fabrics are brushed in way that nap or pile runs in same directiono Napping Fiber ends are brushed up onto fabric surface to achieve deeper pile Usually made from fabrics with LOW twist yarn Machine with hook like projections catch fiber and pull them to surface Napped fabrics:• Blankets, sleepwear, sweaters, warm active wearo Dimensional stability in fabrics Means little shrinkage4 Wool, cotton, rayon, have LOW dimensional stability because SWELL more in watero Fulled (milled) wool Fabrics are fulled (milled) to give more compact structure Fabrics are subject to mechanical action in presence of moisture with moderate heat Machine circulates a rope of fabric between boards RESULTS: gives wool more compact structureo Fulled wool is DIFFERENT from felt because fulled wool is a CONTROLLED felting operation. Wool cloth may be milled (fulled) to a greater or lesser degree, depending on desired characteristics of resultant fabrics. Milling action tends to begin slowly then increase in effects.Summary Points of Chapter 24:• Fabrics undergo finishing to change aesthetics and performance• Finishing can be mechanical or chemical and can range in durability• Mechanical finishes that change the surface characteristics of fabrics:o Calendaringo Embossingo Napping • Mechanical shrinkage controlo Fabrics may shrink when wet, depending on fiber and construction5o Mechanical process can be used to control relaxation shrinkageo Special processes have been developed to relax or set wool fabricso Thermoplastic fibers can be stabilized by heat settingChapter 25: Chemical Finishes• Functional finishes:o Wrinkle resistanto Fire resistanto Water proofingo Antistatico Antimicrobial finishes• Resin is a repellent/ retardant, resistant meaning SLOWS DOWN process i.e. burning or wetting• Proof (water proof) means COMPLETELY blocks process i.e. burning or wetting• Wrinkle resistant finishes:o Used mainly on cellulosic materialso First available in US in late 1940s but more widely used in 1960so ADVANTAGES of wrinkle resistant finishes: Garments are wash and wear (require little or no ironing) Makes fabrics more dimensionally stable (reduces shrinking)6o DISADVANTAGES of wrinkle resistant finishes Fabric is less abrasion resistant (likely to fray or crock) Difficult to alter clothing (old hems and seams wont iron out and new ones wont press well)• Fabric softenerso Work by COATING yarns to allow some slippage and feel softero Reduce static by covering yarns in oilo DISADVANTAGES Can make oily stains on polyester Reduces absorption• Because flammability of textiles is an important contributor to serious injuries and loss of life and property in fires, there are more regulations about flame resistant finishes than any other finish.• Fire triangle:o In order for fire to be present it must have 3 elements: Oxygen, fuel, and heat• Other functional non visible finishes that can be applied to fabrics:o Antistatico Sun protectiveo Anti mildew/ roto Antibacterial/ microbial finishes7Text Book Summary Points:• Chemical finishes are used widely to add value to textile productso They are mostly applied to padding or curingo Low wet pickup methods save energy• Wrinkle resistant finishes are