DM 120 Exam 2 Study Guide Chapter 4 Yarns suitable for knitting weaving or intertwining to form a textile material A continuous strand of textile fibers filaments or materials on a form Two Categories of Yarn o Spun short lengths of fiber twisted together staple fibers o Filament continuous strands of fiber can be miles long High Twist Natural and manufactured fibers Medium to Low Twist Manufactured fibers and silk Yarn Twist Low 2 12 TPI Medium High 20 30 TPI Super High crepe filament yarn Two Types of Yarn Twist o S Twist spiral runs upward to the left Absorbs more moisture Counterclockwise o Z Twist spiral runs upward to the right More dense and stronger yarn less absorption Clockwise Single If untwisted they will come apart Ply o Usually a Z Twist Two more singles twisted together o Usually an S Twist Cords Ply yarns brought together to make Types of Yarns o Staple Spun Yarns short lengths of fiber twisted together Fuzzy surface easy to pill because many breaks Greater amount of twist than filament Thiner Insulative low twist better insulation high twist better wind resistance o Natural o Woolen made of carded yarns More surface area insulative Softer Fabrics Nappy Face o Worsted made of combed yarns Tightly twisted and oriented firm crisp dense fabric with clear face Gabardine Suiting Fabric Synthetic Yarns Bulk Continuous Filament BCF Greater covering power or apparent volume compared to smooth filament yarn Bulky Stretch Textured o Add comfort and stretch to woven fabrics o More bulk cover and elasticity made from polyester or nylon leotards Stretch Textured Yarns stretch pants etc Bulk Textured Yarns Set textured stretch almost melted into shape High bulk with low stretch yarns undergo additional heat setting step to eliminate Novelty Yarns deliberate irregularities Seed Nub Slub Boucle Spiral Corkscrew Chenille Yarns Chenille Yarns soft pile on surface Made with Leno weave fabric then cut lengthwise in narrow strips Crisscross leno wrap prevents unraveling Cotton Wool Rayon Nylon Metallic Yarns Production Processes Natural Synthetic o False Twist o Knife Edge Method sharp edge o Gear Crimping crimp Twisted heat set untwisted in one process pass filaments over heated roll pulled over filament passes through heated gears creating a o Suffer Box method o Air Jet Method o Knit Deknit Method form The fabric is rolled up heat set and then unraveled Filaments knit into a narrow diameter tubular Chapter 5 Weaving Warp Vertical Direction o Runs parallel to the Selvage the edge of the fabric o Runs the length of the cloth o Has the least amount of stretch in a woven fabric Weft Fill Horizontal Direction o Runs the width of the cloth o Fair amount of stretch Bias o Fabric turned to a 45 degree angle o Most stretch you can get in a woven fabric Woven Fabrics interlacing yarns at right angles o Warp Ends length wise yarns o Fill Weft Picks width wise yarns o Selvages lengthwise edge of fabric o Grain direction parallel to warp or filling o On Grain fabric cut parallel to either the warp or filling yarns o Off Grain direction not parallel to either yarns Fabric Features Selvage 1 2 Warp and Filling yarns Warps are thin and strong Face and Back o Face right side o Back wrong side Top and Bottom o Pile Fabrics Velvet Corduroy Yarns Per Inch o 80x70 80 ypi in warp 70 ypi in fill o A measure of quality High YPI strong heavy better hand less distortion better abrasion resistance More Costly Determining the Weave of a Fabric Weave Float o Float one yarn does not interlace but passes over two or more adjacent yarns Basic Fabric Weaves Plain Weave Simplest most used weave Firm construction Strong and ravels less Good for base printed fabrics Tends to wrinkle Ribbed Plain Weave Filling yarns are thicker than the warp yarns o Characteristics Max number of interlacing No technical face or back Plain surface for printing finished Less absorbent Used in apparel Interiors and technical goods Balanced Plain Weave number of filling Lightweight Widest rage of end uses number of warp equals o Very thin transparent semi transparent due to strong fine combed or filament yarns low count or both high count with very fine yarns o Sheer georgette chiffon voile organdy and organza o Opaque slightly larger yarns may have higher count lawn batiste china silk challis o Most common for apparel Durable widest range of types and uses and quality levels o Medium size yarns medium size count o Print cloth percale plisse chintz polished cotton muslin Mediumweight gingham chambray taffeta Heavyweight o Bottom or suiting weight More durable more resistant to wrinkling larger yarns ravels more if count is low o Crash burlap tweed suiting homespun butcher rayon flannels Unbalanced Plain Weave Rib or Rep o Many more yarns in one direction than the other Rib of warp yarns increases 2x more than weft Warp Faced Warp yarns from fabric surface o One set of yarns forms fabric surface wear concentrates on this yarn set o Yarn size differs between warp and fill o Lightweight not common dimity crepe de chine o Mediumweight common broadcloth taffeta shantung o Heavyweight common poplin faille flannelette Bedford cord Basket Weave two or more warp yarns interlace two or more filling yarns Monks Cloth Twill Weaves Right Hand Left Hand Balanced Warp Faced Fill Faced Twill Angle Steep Twills higher than 45 Reclined Twills less than 45 Herringbone is an example of a broken twill More YPI strong compact heavy durable Denim Gabardine worsted combed and tightly oriented Serge Chino Short Floats Snapping is a non Issue Suiting Houndstooth Tweed Medium to heavy weight Usually wool fuzzy surface Novelty Yarns Used for suiting and coats Filament Yarns Satin Weave Warp on Face Smooth and Lustrous o Not lustrous like Satin o Heavier Crepe Back Satin Sateen durable cotton fabric spun yarn filling faced satin weave o Warp Yarns fine little or no twist Make up the face Shiny and smooth o Fill yarns highly twisted o Make up the back o High twist gives a pebbly appearance Special Fabric Weaves Pile Weaves raised surface velvet corduroy terry cloth Woven Pile Fabrics extra warp or fill yarns 2 Basic Types Warp Pile Fabrics extra set of warp yarns Filling Pile Fabric extra fill yarns Cut Pile Weave Fabric when pile is cut Uncut Pile Weave Fabric pile is not cut Double cloth pile weaving knife cuts pile warp yarns to make two velvet fabrics V or W shape Double cloth two sets of fabric made with one wrap o Can be made with different heights of pole o