FASH 15 textiles finishing

1. FASH 15 textiles finishing

2. finishing—an overview • finish—any process that is done to fiber, yarn or fabric either before or after fabrication to change: • appearance—what is seen • hand—what is felt • performance– what fabric does • all finishing processes add to cost

3. finishing—an overview

4. fabric production—fiber processing • EXAMPLE: • cotton polyester blend • cotton fibers are processed separately from polyester fibers • polyester produced as filament tow, crimped, cut or broken into staple fibers • cotton needs considerably more processing—grown, picked, ginned, baled, shipped, grade assessed

5. fabric production—yarn processing • fibers are aligned, blended & twisted • cotton & polyester bales are opened • fibers are loosened and aligned • cotton bales blended to ensure fabric performance and quality • fibers often combined in drawing or roving stage • once fibers are blended, appropriate amount of twist is added to yarns • spun yarns wound on bobbins • shipped to mill for fabric production

6. fabric production—yarn preparation • involves several steps • sizing (mixture of natural starches & synthetic resins) coats warp yarns to reduce abrasion & tension of weaving • fabrication follows sizing—fabric woven, knitted or created in some other manner • preparation & pretreatment of fabric next— • improving absorbency • reducing shrinkage • removing impurities • whitening

7. fabric production—fabric preparation handling —refers to the physical form of fabric during finishing—width, length & fabrication singeing—burns any fiber ends projecting from surface of fabric desizing—sizing added to warp yarn removed cleaning—warp sizing, dirt & oil are removed scouring—general term referring to removal of foreign matter or soil from fabric prior to finishing or dyeing

8. fabric production—fabric preparation • bio-polishing—use of cellulase enzyme treatment to remove fuzz from spun cellulosic yarns • bleaching—process of whitening fibers, yarns, or fabrics by removing irregular natural color • optical brighteners—also used to whiten off-white fabrics—not bleaches; mask yellow by absorbing light • mercerization—treating cellulosic fabric or yarn with an alkali to increase luster, strength, and affinity for dyes • tension • slack

9. fabric production—fabric preparation ammoniating finish—less expensive alternative to mercerization used on cotton & rayon; treated with weak ammonium solution at high temps coloration—color normally added at this stage special purpose finishes—usually follow dyeing to avoid interference with fiber dye absorption; wrinkle resistance, soil-release, & fabric softening appropriate for cotton/poly blend drying—especially frequent with cellulosics to minimize mildew & weight

10. fabric production—fabric preparation tentering—supplies lengthwise & crosswise tension to fabric while it dries to produce uniform length & width

11. fabric production—fabric preparation tentering—supplies lengthwise & crosswise tension to fabric while it dries to produce uniform length & width loop drying—drying fabrics with soft finish (towels & knits) without tension on loop frame heat setting—fabric placed on tenter frame and passed through oven to set and special purpose finishes calendaring—mechanical finish performed by series of rollers between which fabric passes; simple, friction, moire, schreiner, embossing http://www.youtube.com/watch?v=0jjHPHj9EJA

12. fabric production—reworking • includes inspecting fabric for defects & flaws • fabric inspection—done by moving fabrics over an inverted frame in good light • repairing—corrects flaws marked by inspectors when economically feasible • Broken yarns clipped • Snagged yarns worked into fabric • Defects marked so adjustments can be made

13. finishing steps for wool crabbing—finishing process used to set wool fabrics; immersed in hot water then cold water & passed through rollers decating—produces a smooth, wrinkle-free finish and lofty hand on woolen & worsted fabrics; comparable to steam ironing carbonizing—treatment of wool yarns or fabrics with sulfuric acid; destroys plant matter and allows for more level dyeing pressing—woolen fabric placed between metal plates that steam & press

14. environmental concerns & sustainability • finishing transforms a harsh, unattractive fabric into an attractive one—environmentally the impact can be significant • uses significant quantities of energy & water, potentially hazardous chemicals • systems are in place for air-pollution control, pollution prevention, & pollution reduction • less hazardous chemicals used • reclaim & reuse of chemicals • excess use of chemicals, water & energy being regulated