Normal Sequences of Make A Fabrics in Final Exam - Study Guide | HUEC 2040, Study notes of Biology

Download Normal Sequences of Make A Fabrics in Final Exam - Study Guide | HUEC 2040 and more Study notes Biology in PDF only on Docsity! 1 HUEC 2040 - Final Exam – Review 100 points – Chapters 16, 17, 18, 19 Spring 2014 ---------------------------------------------------------------------------------------------------------------- Chapter 16 - Finishing - An Overview Finish - Anything done to fiber, yarn, or fabric either before or after fabrication to change the appearance, hand, & performance of the fabric Normal Sequence to Make a Fabric - Fiber processing → Yarn processing → Fabrication preparation → Fabrication → Finishing preparation → Whitening → Coloration preparation → Coloration → Finishing → Rework - Finishing done by converters or mills Finishes Finish Life - Permanent - for life of product - Durable - for life of product, diminishes with time - Temporary - until conclusion of first cleaning cycle - Renewable - can be replaced Finishes - Visible (can be seen) or invisible (see effect) Fabric Terms Gray, grey, or greige goods - Fabrics after fabrication - But before finishing Loom state - Yarn dyed fabrics after fabrication - But before finishing Converted or finished goods - After finishing Mill-finished goods - Finished by mill Water-Bath Finishing Standard in industry - Uses tremendous amounts of water Water requirements - Clean, neutral pH, free of inorganic contaminants Potential for water pollution high - Unless treated before discharge into public water systems Water quality regulated in many parts of world 2 Developments in Finishing Foam finishing - Foam carries finishing agent - Less water - Less uniform than water finishes - Less energy to move & dry fabrics, quicker process Solvent finishing - Use solvent, less common - To improve quality Computer control - Less labor, high quality finished goods Combine steps to decrease costs & environmental impact Enzyme finishes - Alternate to use of synthetic & inorganic chemicals Enzyme Finishes - Sustainable - Uses less water - Function at lower temperature - Requires less waste water treatment - Produces fabric with better hand & less damage Rinsing - Reducing number by combining & reducing finishing steps Plasma Technology - New way of applying thin, inexpensive, functional coatings to fabric Routine Finishing Steps Described for all cotton or cotton/polyester suiting weight - But similar for most fabrics Fiber processing - Fibers processed separately Yarn processing - Fibers aligned, blended, twisted Yarn Preparation - Slashing or sizing - Warp yarns coated with mixture of natural & synthetic resins (sizing, starch, gum, lubricant, or preservative) to increase abrasion resistance Fabrication - Fabric woven, knit, or other process Fabric Preparation Handling - Physical form (length & width) of fabric during finishing - Run - Quantity of fabric receiving same processing at same time - Open width or tubular/rope form continuous or batch process Singeing - Burn off fiber ends to minimize pilling - Smoother fabric surface Desizing - Sizing on warp removed by physical agitation or chemical (enzyme or acid) - Process depends on fiber & sizing - Environmental impact/sustainability - Water pollution, bio or enzyme desizing saves water, energy & time, but more expensive Cleaning - Warp sizing, dirt, oil or other soil removed 5 Chapter 17 - Aesthetic Finishes Aesthetic Finishes - Change appearance or hand - May change fabric name - Process additive or subtractive - Many possibilities from same gray goods - Permanence related to fiber content & technique Equipment Padding Machine - Applies finishes & dyes - Liquid or paste form Backfilling Machine - Variation of padding - Also - applies finishes - To 1 side only - Usually back Luster Finishes - Changes light reflectance - Improve fabric’s luster - May be all over or localized - Done by calendaring - Cylinder or roller Luster Finishes Glazed - Friction calendar - 1 cylinder rotates faster than other - Fabric passed through finishing solution - Partially dried - Polishes or glazes surface - Glazed chintz, polished cotton Ciré - Similar to glazed - Hot calender glazes surface - High gloss - Greater luster on surface - “Wet Look” - Ciré taffeta, ciré satin Plasticize - Very thin polymer layer - Higher weight fabrics - Higher pronounced glaze - Slicker glace surface - Soil-resistant & water-repellent Moiré - Wood grain or water-marked design on ribbed fabrics - 2 fabrics calendered or etched calendar - Moiré taffeta, moiré ottoman Schreiner Calender - Metal roller engraved with fine lines for deep luster - Flattens yarn for smoother appearance & better cover - Satin, sateen, damask, tricot, etc. Embossed Calender - Melt design on thermoplastic fabric surface - Controlled surface glazing 6 Drape - Finish modifies drape of fabric Crisp & Transparent Parchmentize - Treat cellulose with sulfuric acid - Subtractive process - Tendering - Weakening of the fabric - Organdy Burned-Out (deglaze) - Print chemical on blended fabric that dissolves one fiber - Creates sheer areas - Fray & not very durable - Rayon & polyester or nylon & silk Sizing or starching - Fabric immersed in mixture - Waxes, oils, glycerine & softener - Gelatin – rayon - Resin-based - permanent - Temporarily adds body & weight Weighting - Metallic salt added for stiffness - Mineral weighted silk – rare today - Sensitive to light damage Texture & Hand Finish alters texture & hand of fabric - Can feel effect of finish Embossed - Produces raised or 3-D design - Embossed cotton Pleated - Variation of embossed - Paper-pattern technique - Costly hand process - Wide variety of pleated designs - Machine-pleating or running process - Blades pleat fabric inserted between 2 heated rolls - Paper backing, paper tape - Heat set Puckered Surface - Chemical printed on nylon or polyester - Partially dissolve or swell fabric surface - As it dries - It shrinks & creates puckered surface Plissé - Print stripes with sodium hydroxide on cotton fabric - Shrinks treated areas - Untreated areas pucker Flocked - Add surface fiber with adhesive - Localized or all-over effect Embroidered - Stitch thread on fabric surface - Figures very durable - Eyelet embroidery & others Expanded Foam - Compound design expands with heat - 3-D texture Sheared - Pile or nap cut to controlled height - Patterned, smooth or sculptured effect Brushed - Fiber ends swept off fabric after shearing 7 Napped - Brush fibers to surface for fuzzy, soft hand - Increased warmth & beauty - Contributes to water & soil repellency - Flannel, flannelette & fleece Crepeing - Special compacting process for soft hand & drape,comfort stretch - Fabric is fed into the machine by a special blade at a faster rate than it is removed from the machine Fulled – Milling - Controlled shrinkage (compacted) of wool fabrics - Moisture, heat, soap or acid, pressure - Improves hand & appearance Beetled - Mechanical flattening of yarns to make weave appear tighter with increased luster, absorbency & smoothness - Contemporary method - High pressure, resin & thermoplastic fibers - Damask, crash Coronized - Heat setting, dyeing & finishing glass fiber - 1 continuous operation - Softens yarn to bend & crimp Emerized, Sueded or Sanded - Fabric abraded to split fibers - Create soft hand & sueded texture - “Peach skin” look Abrasive, Chemical or Enzyme Wash Chemical Wash - Chemical alters fiber surface Abrasive Wash - Chemically saturated abrasive material tumbled with fabric Enzyme Wash (similar to stone washing) - Cellulase enzyme removes surface fuzz - Decreases pilling & fabric weight Figure 17.19 - Enzyme-polished cotton fibers - Original fibers (left) & bio-polished fibers (right) Silk Boil-Off - Remove sericin to create looser, more mobile yarns Caustic (or alkali) Treatment - Dissolve portion of fiber for greater yarn mobility Hand Builders - Slippage between yarns & fibers - Softens fabric hand - Improved durability - Better wrinkle resistance - Silicone softeners & cellulase enzyme ---------------------------------------------------------------------------------------------------------------- 10 - Cellulosic fibers – wrinkle most - 1929 - Cotton & rayon - Urea-formaldehyde resin - Penetrated into fiber, thermoset - 1950s - Wash-and-wear - Eliminated need of ironing Permanent Press - Fabric preparation critical - Sew, dye & finish product first - Additives control hand & performance - Puckering, decreases strength - Difficult & expensive Durable Press – Problems - Increased oil attraction & Reduced water penetration - Stiffness - “Fishy” odor - Not properly rinsed - Gone after 1 or 2 launderings - Safety – OSHA - Formaldehyde Appearance Retention Finishes Soil & Stain Resistant Finishes - Minimize soil attraction or maximize soil removal - Oil-borne stains released or resist redeposition - Prevents soil from adhering & increases wettability - Carpet - DuPont’s Stainmaster™ - Function like colorless dyes - Combine modified fiber, stain resistant finish & compound blocks fiber dye sites Stain Repellency - Stain-resistant finishes - 3M Co. Scotchgard™ - Repels water & oil/grease - Decreases surface energy - Water or oil beads up Appearance Retention Finishes (cont’d) Abrasion resistant finish - Acrylic resin increases abrasion resistance Antislip, slip resistant, or nonslip finish - Applied to low count, smooth surface, smooth filament yarn fabrics to bind yarns, reduce seam slippage & fraying - Limited effectiveness & gradually lost during laundering Special Purpose Finishes Antislip Finishes - Slippage - A tendency to slide against one another - Creating flawed areas in fabric or seam slippage problems - Silica compounds - Resins coating 11 Appearance Retention Finishes (cont’d) Fume-fading resistant, anti-fume, atmospheric fading protective finish - Minimize fume fading by preventing reaction between dye & fumes Surface or back coating - Metallic coating - on back to reduce heat transfer - Plastic coating - Minimize slippage, snagging - Adds body & leather-like look - Acrylic foam - Reduces air permeability - Increases thickness & finishes back - Latex back coating - Binder for tufted fabrics - Light-stabilizing finish - Light stabilizers or ultraviolet absorbers minimize damage from light - Important for some interior & technical products - Pilling resistant finish - Minimize pill formation - UV light or oxidative solution causes fiber ends to break off rather than form pills Comfort-Related Finishes Waterproof fabrics - Prevents penetration of water – no water penetration - Rubber or synthetic plastic coating - Warm & uncomfortable – barrier traps air & perspiration Water repellent finish - Resist wetting & combine finish with fabrication - Fluorocarbons - Improve water repellency - Wax emulsions or metallic soaps – Renewable - Resins on surface are active agents – Durable finish - Silicones - Most common – Durable - Good drape, soft hand & stain resistant Waterproof Garments - Seamlines must be sealed - Sewing needle holes – leak- Tears, rips, worn spots – leak - No air or moisture passage - Powder detergents & cold temperatures - No liquid detergents - Surfactants (soaps) allow wetting Porosity control finish limits penetration of air - Keeps out water, allow moisture/vapor passage - Waterproof & Breathable Fabrics (WP/B) Water absorbent finish - Increase moisture absorbency – Surface coating of synthetic fiber fabrics 12 Ultraviolet (UV) absorbent or (UV) blocker finish - Incorporate chemical compound that absorbs energy from UV light - Improves ultraviolet protective factor (UPF) of fabrics - May include dyes & fluorescent whitening agents Anti-static finish - Improves surface conductivity, attracts water, develops opposite charge, or combination - Synthetic fibers are poor conductors of electricity - Clings & has electric shocks - Fabric softeners – limited effectiveness - Softens hand - May increase absorbency - Coats the fiber surface - Attracts moisture to fiber - Polymer modification before extrusion - High-performance antistatic fibers - Metal, metallized, bicomponent - Sprays, fabric softeners Phase change finishes - PCM – phase change material - Incorporate phase changing compounds (micro-encapsulated or nanoparticles) that absorb or release heat during phase change (liquid to solid or vice versa) - May alter other performance characteristics - Minimize heat flow through fabrics – warms/cools body - Increases moisture absorbency Biological Control Finishes Insect & moth control finish - Repel insects by odor, poison or unpalatable taste - Wool, moth proofing (cystine) - Poison larvae or alter fiber will not eat - Silk lacks cystine, not attacked Mold & mildew control finish - Chemicals prevent mold/mildew growth - Cellulose fibers most susceptible to mildew Rot proof finish - Antiseptic finish – copper solution - Protect tents, awnings, lawn furniture from rotting Antimicrobial, antiseptic, antibacterial (biocides) or bacteriostatic finish - Controls disease spread & reduces infection - Inhibits bacterial growth - Prevents decay & perspiration damage - Ammonium compounds - Diaper rash - Metal compounds - Toxic to bacteria Microencapsulated finish (smart textile) - Fragrance, insect repellant, disinfectant, cleaning agent, etc. in tiny capsules (nanoparticles) sprayed on & bonded to fabric - Semi-durable - for interiors, apparel, protective clothing 15 Dyes - Soluble - Dispersible in the fiber - Forms bond with fiber - Fiber specific - Fiber chemistry restricts dyes used - Only certain combinations of dye class & fiber type work - High color strength - Fastness varies by dye & dye class Dye Classes Acid (anionic) - Protein fiber dyes - Bright colors, poor wet fastness, may have poor light fastness Azoic (ice dyes) - Cellulose fiber dyes - Cotton, viscous rayon, some polyester - Bright shades - Good fastness to light & water - Poor crocking - Water insoluble Cationic (basic) - Acrylic, wool, some polyester & nylon - Good fastness on synthetics, but poor on natural fibers - Bright colors – silk Developed direct - Direct dye + metal (mordant) - Cellulosic fibers - Good light fastness, fair wash fastness - Duller colors Direct - Cellulosic fibers - Inexpensive, Poor fastness - Most commercially important class Disperse - Synthetics – acetate, polyester - Good fastness - May fume fade - Disperse in water without dissolving, dissolves in the fiber Natural dyes - Minor dye class - Best on protein, nylon & cellulosic fibers - Renewable & sustainable - Animal, mineral & plant sources - Limited colors & availability 16 Dyes - Cellulosic Fibers - Vat Dyes - Water insoluble, expensive - Wash, light fastness - Sulfur Dyes - Dark colors - Wash, light fastness - Inexpensive - Reactive Dyes - Wash fastness Natural Dyestuff Fabric Treatments - Natural acids or oxides - Improve colorfastness - Mordants - React with dyestuff & fiber Colored lake – “fixing” the color - Duller colors, excellent fastness - Depends on type of metallic material & fiber Vegetable Dyes Woad - Herb plant - leaves - Blue dye - Replaced by indigo Madder - Red dyestuff - Herb root, dried - Metallic salts - Wider color range Safflower - Old World herb - Orange or red flower heads - Red dyestuff - Seeds - oil Fustic - Tropical American tree - Yellow dyestuff - Yellow, gold, browns, green Logwood - Plants, trees – pod/seed - Permanent black dyestuff - Violet, silver, gray, black Cutch - Brown dyestuff - Hard brown, reddish brown - Tropical Asiatic plants Animal Sources Kermes - Brilliant scarlet dyestuff - Unlaid eggs of insect - Dried bodies of small female insects Cochineal - Vivid red, colorfastness – wool - Small dried insect bodies – South America Shellfish - Oxidized white liquid from shellfish - 1,000 B.C. - White, green, red, deep purple - Expensive – robes - Tyrian purple - Trade item - “Royal Purple” - Tyrian Purple Murex Shell Synthetic Dyes William Perkin, 1856 – Chemist - Aniline - Coal tar - Mauve - Reddish-purple - 1st synthetic dye Dyes - Manufactured Fibers Basic Dyes - Cationic dyes (+) - Silk - bright colors, poor laundering fastness - Synthetic – excellent colorfastness Disperse Dyes - Manufactured fibers – acetate, polyester - Good fastness, fume fading 17 Manufactured - Dyes Classifications Vat Dyes - Water insoluble, expensive - Good fastness - Dull colors, limited color range - Environmental concerns - No longer used in U.S Sulfur Dyes - Dark colors - Good fastness – Inexpensive Reactive Dyes - Good to excellent fastness - Bright, pure colors - Usually cellulosic Dyeing Process Water - Most used medium Dye Liquor - Dye Solution - Agitated, circulated - uniform dyeing Dyeing Process - areas discussed 1. Affinity of the dye - Fiber type - Mordants - Surface - Fabric preparation - Amorphous areas 2. Exhaustion - Amount of transfer of dye from dye bath to fiber/fabric 3. Levelness - Even distribution of the dye - Streaking 4. Dye Retention - Physically trapped - Soluble in water – Binder Stages of Dyeing 1. Fiber Solution Stage - Mass Pigmentation - Solution dyeing, spun or dope dyed - Add colored pigments to spinning solution - Sensitive – light, bleach - Color integral part of fiber - “Locked-in” color - Limited color range - Basic colors 2. Stock or Fiber Dyeing - Fibers dyed before yarn processing - Usually staple fibers - Tweed, heather effect - Untwist yarns – identify stage - Different colored fibers, uniform in color 3. Yarn Stage - Dye in yarn stage - Before weaving or knitting - Identify - Different color yarns, even color - Stripes, plaids or structural design fabrics - Dyed in skeins, packages or on beams - More expensive than piece dyeing