Week 2 Performance Characteristics of Materials PDF

1.2 Performance Characteristics of Materials Natural plant/cellulose fibres Cotton: Cotton is the most widely used natural plant/cellulose fibre. It comes from the seed fibre found in the cotton bolls of the cotton plant. Properties/characteristics of cotton and its uses: Properties/characteristi...

1.2 Performance Characteristics of Materials Natural plant/cellulose fibres Cotton: Cotton is the most widely used natural plant/cellulose fibre. It comes from the seed fibre found in the cotton bolls of the cotton plant. Properties/characteristics of cotton and its uses: Properties/characteristics Examples Uses Naturally breathable, conducts heat away Calico, terry towelling, Apparel fabrics: shirts, dresses, jeans, from the body. muslin, flannel, voile, underwear, socks, uniform. Very absorbent. winceyette, chambray, Home textiles: towels, sheeting, Non-static as moisture is present. poplin, denim, drill, curtains, soft furnishings, throws. Good strength due to its natural twist. gingham, madras, Commercial textiles: medical Very little elasticity, creases easily. seersucker, corduroy, dressings, nappies, sewing threads, Highly flammable. velvet, knitted jersey, ropes, filter. Poor insulator. velour. Leisure textiles: tents, awnings, boat Comfortable and soft handle. sails, bags, sportswear. Damaged by mildew and prolonged Blended and mixed, usually with sunlight exposure. polyester, wool and elastane. Biodegradable. 1.2 Performance Characteristics of Materials Cotton fibre production: Cotton grows in a boll around the seeds of cotton plants. Harvesting is carried out by hand or using a picking machine. The fibres are separated from the seeds using a process called ginning. Mechanical purification is used to remove foreign matter. The fibres are sourced to remove the natural wax coating from the surface of the fibres. The processed cotton fibres are spun into staple fibre yarns. 1.2 Performance Characteristics of Materials Natural plant/cellulose fibres Linen: Linen is one of the most expensive natural fibres. It is labour- intensive to produce so is produced in small quantities. Linen comes from the bast fibre of the flax plant stem. Properties/characteristics of linen and its uses: Properties/characteristics Examples Uses Highly absorbent, naturally breathable. Crash, duck, Apparel fabrics: summer or tropical Very strong due to the longer length of huckaback, interlining, garments. the staple fibres. Holland, union (half Home textiles: tablecloths, dish towels, Poor elasticity, creases easily. linen - fabric has cotton bed sheets, curtains. Highly flammable. warp yarns and linen Commercial textiles: lace, trimmings, Poor insulator. weft) ropes, tarpaulins, sewing thread. Flat surface reflects light, so it has a Leisure textiles: awnings, art subtle lustre. canvases. Poor drape and stiff handle. Blended and mixed, usually with Damaged by mildew, sweat and bleach. cotton. Biodegradable. 1.2 Performance Characteristics of Materials Linen fibre production: The fibres are loosened from the flax plant stems using a process called retting. The retted stems are crushed in a process called scotching to separate the fibres from the woody outer bark. The fibres are heckled (combed) to remove the short fibres, leaving the long fibres. The processed linen fibres are spun into staple fibre yarn. 1.2 Performance Characteristics of Materials Natural plant/cellulose fibres Ramie: Ramie is one of the oldest natural fibres. The high cost of fibre extraction and production reduces its competitiveness, however consumer demand for sustainable fibres is leading to increased use. Ramie fibres can be harvested from the same plant up to three times a year, making it highly sustainable fibre source. Properties/characteristics of ramie and its uses: Properties/characteristics Examples Uses Good absorbency, breathable. Ramie Apparel fabrics: lightweight Keeps its shape and does not shrink. summer use. Harder to dye than cotton. Home textiles: table linens, Naturally white in colour. dish cloths. Has good strength. Commercial textiles: ribbon, Poor elasticity, creases easily. sewing thread, sacks, twine Highly flammable. and cord. Poor insulator, cool to wear. Mostly blended with cotton, Smooth lustrous appearance. wool, polyester or acrylic. Stiff and brittle handle. Resistant to mildew, light and insect attack. Biodegradable. 1.2 Performance Characteristics of Materials Ramie fibre production: The stems are harvested by cutting above the root. A laborious process of decortication (scraping and pounding) is used to remove the bark of the stem. The raw fibres are washed, dried and degummed using chemicals to extract the spinmable fibre. The processed ramie fibres are spun into staple yarn. 1.2 Performance Characteristics of Materials Natural animal/protein fibres Wool: Wool comes from the fleece of a sheep. Wool fibres are classed according to their fineness, length, crimp and the breed of sheep they come from. They are staple fibres made from long chains of protein molecules. Properties/characteristics of wool and its uses: Properties/characteristics Examples Uses Water repellent and excellent moisture absorption. Worsted, baize, Apparel fabrics: coats, suits trousers, Anti-static as moisture is always present. flannel, jersey, sweaters, hats, scarves, gloves, Heat, moisture and mechanical action shrink and tweed, serge, socks. felt the fibres, making wool difficult to care for. fleece, tartan. Home textiles: blankets, carpets. Adequate strength but not very durable. Commercial textiles: loft insulation, High natural fire resistance, self-extinguishes if set noise insulation. alight. Leisure textiles: horse rugs, athletic Excellent elasticity, the natural crimp provides and leisure wear. ‘springiness’, enabling creases to fall out. Blended and mixed usually with Good insulation/thermal qualities. cotton, silk, polyester, acrylic and No lustre because the fibres are not smooth. other animal hair fibres. Origin, fineness and length of fibre determine the Sportswool is a mix of merino wool handle of wool fabrics. Wool can be soft or itchy. and polyester fibres. The wool draws Biodegradable. moisture away from the body, which is wicked away by the polyester, keeping the wearer cool. 1.2 Performance Characteristics of Materials Wool fibre production: Shearing: the sheep’s fleece is removed by hand typically once a year. Sorting: the sheelonger fibres are separated from the shorter fibres. The longer fibres are processed through the worsted system to make high-end products such as suits. The shorter fibres are processed through the woollen system to make products such as blankets and sweaters. Carbonising and scouring: carbonising is a chemical process that removes vegetable matter such as seeds and grass. Scouring is a mechanical process that washes the fibres to remove the lanolin and dirt. Carding: disentangles clumps of fibres, aligns them parallel to one another in a web, which is then condensed into a continuous strand of fibres called a sliver. The sliver is processed further using a roving machine to compact and hold the fibres closer together, minimising the chance of breakage during spinning. Spinning: the rovings are fed into a mechanised spinning machine and a predetermined amount of twist is applied. The yarn is re-wound onto suitable packages for knitting or weaving. 1.2 Performance Characteristics of Materials Natural animal/protein fibres Animal Hair: Luxurious animal fibres are expensive due to limited supply. They include: Cashmere, from the undercoat of cashmere goats Mohair, from angora goats Angora, from angora rabbits Properties/characteristics of animal hair and its uses: Properties/characteristics Examples Uses Hair fibres have similar Cashmere fibres are very soft, Apparel fabrics: luxury coats, qualities to wool fibres: lightweight, lustrous and three times suits, knitwear, shawls. Naturally fire resistant more insulating than wool. Very good thermal Home textiles: luxury interior insulators Mohair fibres are long, lightly curled and textiles. Soft, luxurious handle have a silky lustre. They are naturally and appearance elastic, crease resistant and dye well. Can be used alone or blended Biodegradable with wool to reduce the cost. Angora fibres are very fine and lightweight. A hollow core makes the fibres very good at absorbing moisture vapour. 1.2 Performance Characteristics of Materials Animal hair fibre production: In the case of cashmere and angora, the fibres need to be washed and de-haired to remove the coarse guard hairs before being spun into yarn. Angora gourds are shorn twice a year to collect the mohair fibres. The fibres are processed in a similar way to wool fibre sbut extra care is taken to try and keep the delicate fibres clean and free of debris. A wide range of animal hair fibres is used in the textile industry. Other examples include camel, alpaca, vicuna and horsehair. 1.2 Performance Characteristics of Materials Natural animal/protein fibres Silk: Cultivated silk comes from the cocoon of the Bombyx mori silkworm. Vegans and animal rights activists consider cultivated silk production to be unethical as in commercial production, the moth is killed before it can emerge and damage the cocoon breaking the filament fibre. Production of wild silk is on a smaller scale than cultivated silk. Wild silk comes from the cocoon of other species, for example the tussah silkworm. It is harvested after the moth has left the cocoon. The cocoons differ in colour and have a natural slub texture in the filament. Wild silks tend to be more difficult to unravel as the cocoon has been damaged. Properties/characteristics of silk and its uses: Properties/characteristics Examples Uses Excellent tensile strength due to the long Bourette, chiffon, crêpe Apparel fabrics: formal wear, ties, continuous length of the fibre. de Chine, duchesse, houses, lingerie, scarves. Very absorbent. habutai, organza, Home textiles: , wall hangings. Anti-static as moisture is always present. pongee, satin crêpe, Commercial textiles: surgical sutures, Weak when wet, so is hard to care for. taffeta, wild silk (tussah, sewing and embroidery threads, Extensible and elastic. Honan, shantung) ribbons. Does not burn easily, self-extinguishes. Blended as a staple fibre with wool. 1.2 Performance Characteristics of Materials Properties/characteristics Examples Uses Cool and warm. Naturally lustrous. Pleasant handle and comfortable to wear. Has fluidity and drapes well. Weakened if exposed to sunlight and sweat. Biodegradable. Silk fibre production: The silkworm produces the fibre when it pupates. Two filaments of silk fluid are extruded from spinnerets below the silkworm’s mouth. Sericin (silk gum) coats the filaments and holds them together to produce a single filament fibre which, when wound around the body of the silkworm, creates a cocoon. To extract the fibre, cocoons are degummed by soaking them in boiling water. This kills the moths and softens the sericin. The long continuous fibre is unwound (reeled) from the cocoon and is spun with three to ten silk fibres to form a filament yarn. 1.2 Performance Characteristics of Materials Regenerated Fibres Manufactured Manufactured regenerated fibres are made from natural cellulose that has been chemically modified. Other examples of manufactured regenerated fibres include cupro, alginate and rubber. Key term Solvent: a chemical substance used to dissolve or dilute other substances or materials. Absorbency: a fabric’s ability to retain moisture; its affects a fabric’s comfort, ease of care, dye-ability and static build-up. Spinneret: the nozzle part of the spinning machine where the molten fibres are extruded. 1.2 Performance Characteristics of Materials 1.2 Performance Characteristics of Materials The common properties/characteristics of regenerated fibres and their uses Properties/characteristics Uses Their structure allows similar or better levels of Fashion garments, lining fabric, lingerie, trims and absorbency than cotton. ribbons. The shape can be changed using spinnerets with different cross-sections. Can be used in their filament form or cut up and They take dye and print techniques especially well. used as staple fibres. Non-static as some moisture is always present. Easy care, but first generation fibres should not be Used in blends with natural fibres or on their own tumble dried as they are prone to shrinking. because of their reduced environmental impact. Naturally breathable with good wicking properties. Low ability to trap air so cool to wear. First generation fibres have lower strength and resistance to abrasion than cotton. Same or slightly better resistance to creasing than cotton. Softer handle and better drape than cotton. The degree of lustre can be engineered from subtle to bright whereas cotton is a matt fibre. Similar flammability to cotton due to the cellulosic content. Lower resistance to damage from sunlight, bleach and microorganisms than cotton. Biodegradable and recyclable, and inexpensive to produce. 1.2 Performance Characteristics of Materials Regenerated Fibres Manufactured First and second generation fibres Developments in regenerated fibres and have seen improvements in strength, softness and crease resistance. Distinguishing difference in individual First generation fibres regenerated fibres: New generation fibres Viscose: Modal: More absorbent than cotton and other Stretched more than viscose after spinning to regenerated fibres. make fibres stronger. Can be tumble dried. Silky smooth, very soft handle and drape. Acetate: Lyocell (Tencel is a trade name for lyocell): Lower absorbency, prone to static. Stronger and more extensible than cotton so Moe elastic than others but still creases. does not crease as much. Thermoplastic capabilities. Totally biodegradable, recyclable and made Subdued lustre and elegant drape. using a closed-loop system that reduces the chemicals used in the manufacturing process. 1.2 Performance Characteristics of Materials Synthetic Fibres General characteristics of synthetic fibres They are mostly manufactured using the melt spinning process, which produces very fine, smooth continuous filament fibres. The cross-section shape of a fibre can be engineered to give different properties and characteristics. The long, continuous filament fibres can be left in their original state, textured or cut up into staple form. They can be coloured during the manufacturing process (dope dyeing). Their thermoplastic properties enable them to be heat-set, and shaped and finished in a range of ways. The specific properties of each fibre are dependent on their chemical composition but most are very strong, non-absorbent, smooth and lightweight. They come from non-renewable sources and take many years to biodegrade. Key term Thermoplastic: a material that becomes soft and mouldable above a specific temperature and solidifies upon cooling. 1.2 Performance Characteristics of Materials Synthetic Fibres 1.2 Performance Characteristics of Materials Synthetic fibres Properties/characteristics of different synthetic fibres and its uses: Name Properties/characteristics Uses Polyamide (nylon) Low absorbency, dries quickly, does not shrink, Clothing, tights, Produced as continuous smooth prone to static. socks, underwear. filaments including very fine Very strong and durable, high abrasion resistance. Outdoor and active microfibres. Good elasticity and crease recovery. wear. They can be textured or cut into Low flammability, fabric melts and drips. Tents, umbrellas. staple fibres. Thermmosplastic - fibres can be textured, desired Carpets. Microfibre brand names include: creases can be heat-set or inadvertently added to In staple form, it is Tactel Aquator, wicks fabric if washed at too high a temperature. blended with most moisture away from the Lightweight and can have listre if the fibres are fibres. body, used for underwear extruded as flat smooth surfaces that reflect a lot and sportswear fabric. of light. Tactel Diablo, a lustrous Cross-section shape and fibre thickness can be fabric with good drape used engineered to provide fine, smooth, soft fabrics for hosiery and lingerie. that drape well, or thicker, denser, stiffer fabrics. Fibre shape and texturing gives improved comfort and thermal qualities, enabling moisture to wick away from the body. Flat, smooth filaments trap little air so are cool and poor insulators. Weakens in sunlight and chlorine bleach but resistant to chemicals and microorganisms. 1.2 Performance Characteristics of Materials Synthetic fibres Properties/characteristics of different synthetic fibres and its uses: Name Properties/characteristics Uses Aramids Greater strength and durability. Bullet- and stab-proof Technical textiles developed from Stab and tear resistant. vests. polyamide, brand names include: Fine and lightweight. Motor sport clothing. Kevlar Flexible for ease of movement. Industrial work wear. Nomex Nomex has similar properties to Kevlar and can withstand even higher temperatures. Polyester Very similar properties to polyamide. A wider range of Produced as continuous smooth The most commonly used synthetic fibre. clothing, including filaments. Better thermoplasticity qualities than outdoor and active They can be texture or cut into polyamide. wear. staple fibres. Does not weaken in sunlight. Bed sheeting. Microfibre trade name: Trevira Non-renewable source but can be recycled, Lining fabric. Finesse. e.g. Polartec fleece can be made from recycled Sewing thread. drinks bottles. Wadding and fibre fill. 1.2 Performance Characteristics of Materials Synthetic fibres Properties/characteristics of different synthetic fibres and its uses: Name Properties/characteristics Uses Acrylic Low absorbency, prone to static. Knitting yarn. Spun using the wet or dry Easy care, dries quickly. Knitwear. spinning method. Good strength. Fake fur. Mostly used as bulky staple Sensitive to heat and highly flammable. Carpet. fibres. Good elasticity, crease resistant. Soft furnishing fabrics. Good thermal qualities, soft and warm. Blended with wool or Wool-like handle, with good drape. polyester. Poor lustre. Chlorofibres (polyvinyl) Strong. Raincoats. Used in filament or staple form or Durable. Showerproof coatings. as a coating. Breathable, easy care, waterproof. Thermal clothing. Good insulator. Active sportswear. PVC can be recycled. Socks and underwear. 1.2 Performance Characteristics of Materials Synthetic fibres Properties/characteristics of different synthetic fibres and its uses: Name Properties/characteristics Uses Fluorofibers (PTFE) When applied to fabric as a finishing process, Used to protect fabrics, Used mainly as a coating. the fabric is: e.g. school trousers. Trade name: Teflon Water repellent and stain resistant Workwear. Easy care and less energy is needed to Soft furnishings. dry the fabric Shoes. Durable and flexible Breathable but windproof Elastomeric (elastane) Low absorbency and easy care. 1-2% in socks or Always used as the coe in core- Good tera resistance and durability. trousers. spun yarn and combined with Very fine and lightweight. 15-20% as needed in natural and synthetic fibres. Gives a high degree of comfort and allows free swimwear, foundation Brand name: Lycra. movement. wear or sportswear. Increases shape retention, crease recovery and improves draper in woven fabrics. 1.2 Performance Characteristics of Materials Inorganic Fibres Inorganic fibres are not synthetic polymers but are included in the man-made fibre classification. Name Processing Method Properties/characteristics Uses Glass (fibreglass) A direct melt method High tensile strength but low Insulation material in Source: powdered is used to draw extensibility. buildings. mineral filament glass fibres Poor abrasion resistance. Flame-retardant fabrics, compounds. from the molten High heat resistance and e.g. theatre safety mineral compound. thermal conductivity. curtains. The fibers can be Impermeable and unaffected by Strengthened glass, used as filaments or sunlight, chemicals and reinforced plastics. cut into staple fibres. microorganism attack. Hospital wall coverings. Non-stick, non-toxic and reflective. Carbon (graphite Carbon fibres are Very strong for its size. Protective clothing. fibre) twisted together to Lightweight. Intelligent electro- Source: carbon form a yarn that can Abrasion and tear resistant. conductive fabrics for e- created by burning be used by itself or Flame resistant at very high textiles. acrylic fibre. made into a fabric. temperatures. Aeroplane interiors, e.g. Resistant to chemicals. carpets, upholstery fabric. Production of nano-fibres. 1.2 Performance Characteristics of Materials Name Processing Method Properties/ Uses characteristics Metal Very thin layers of Strong and abrasion Decorative fabrics and trims, e.g. Source: metal are laminated resistant. Lurex. copper, between clear film Lightweight. Silver prevents a build-up of bacteria aluminium and and cut lengthwise Withstands high in sports clothing and medical steel for into thin strips. temperatures. applications. common uses. Alternatively, the Good conductor of heat Conductive sewing thread in e- Titanium, gold metal is heated until and electricity. textiles. and silver for it vaporises and Anti-bacterial and anti- special uses.. deposits at high microbial. pressure onto Anti-static. polyester fibres. Stiff handle and high lustre. Ceramic Incorporated into Resistant to 1000⁰C+ Industrial work wear. Source: synthetic fibres by temperatures. Swimwear, e.g. Esmo and Sunfit powdered coating them with Lightwewight and resistant fabrics. inorganic non- ceramic particles or to chemicalals. A fabric’s surface coated with PCCM metallic encapsulating them Produces fabrics with UV deflects heat in hot weather. When materials such in the fibre. protection. applied to lining fabric, it deflects as crystallines Has heat-deflection body heat back to the body. oxide. Carbon properties to regulate body Bioceramic fabric, e.g. Under Armour and silicon are temperature, e.g. Protective Athlete Recover Sleep Wear. also Ceramic Coating Material Production of nano-fibres. considered (PCCM). Thermolite, a lightweight fibre with a ceramics. Has therapeutic properties hollow core used in socks, sleeping if combined with body heat. bags and jackets. 1.2 Performance Characteristics of MaterialsCharacteristics of Yarns Performance Fibres need to be made into yarns before they can be manufactured into woven and knitted fabrics. Yarn can be made from staple fibres (staple yarns) or filament fibres (filament yarns). They can be manufactured with twist using a spinning process or, in the case of some multifilament or monofilament yarns, without twist using a winding process. Low-level twist produces a weaker, softer, bulkier yarn and makes it easier to form a raised nap if the fabric is finished using mechanical brushing. High-level twist produces a stronger, smoother and dense yarn. Too much twist causes the yarn to become crinkly. Crêpe fabric has a crinkled, crisp appearance and is made using highly twisted yarn. Plying a single yarn twisted in the S direction and a single yarn twisted in the Z direction makes a balanced yarn, which is less likely to untwist. Key term Nap: a raised surface made by brushing the fabric surface after weaving. 1.2 Performance Characteristics of Materials Tex and denier are technical terms relating to the formulae used to state a yarn’s thickness. Fibre type, thickness of yarn and the tightness of twist all affect a yarn’s working and aesthetic properties. The choice of yarn is mostly dictated by the end use of a woven or knitted fabric. Key term Tex: the metric system used to state the thickness of a yarn. Denier: a measure of thickness used for all filament yarns. The higher the denier number, the thicker the yarn. 1.2 Performance Characteristics of Materials Types of Yarns Staple Yarns All manufactured fibres are produced as filaments but they are often cut into staple lengths to make staple yarn. This increases the range of yarn and fabric types. Staple yarns are hairy. They give fabrics texture and a soft, fuller handle. They are good insulators and mostly matt in appearance. Longer staple fibres give staple yarns a degree of lustre. Staple yarns are weaker than filament yarns as regularity in the thickness of the yarn is harder to achieve. They are more expensive to manufacture, as more stages and energy are required. Staple yarn can contain two or more different types of fibre. Staple fibres are blended to create aesthetic effects and improve performance and aftercare of fabrics. 1.2 Performance Characteristics of Materials Filament Yarns Filament yarns are smoother and more regular than staple yarns, making them stronger. They give fabrics a more compact handle, a higher degree of lustre but are not so good at insulating. Silk filaments are very fine and need to be lightly twisted with other silk fibres so that they can be made into usable yarn. Man-made fibres are extruded from the spinneret as continuous filaments, which may be grouped together with or without twist to form a multifilament yarn. A monofilament yarn consists of one continuous filament spun from a spinneret with one hole. 1.2 Performance Characteristics of Materials Single Yarns A single or one-ply yarn is a continuous single thread of twisted staple or filament fibres, or a monofilament, or filaments grouped together without twist to make a single yarn. Plied Yarns Plied or folded yarns are made by twisting two or more single yarns together. Twisting the yarns together in the opposite direction to the way they were spun achieves uniform thickness and strength, and makes products like sewing thread fit for purpose. The use of single yarns made from different fibres or colours achieves special effects in plied and corded or cabled yarns. 1.2 Performance Characteristics of Materials Core-spun Yarns Core-spun yarns are multicomponent yarns. They have a filament core and a sheath made from staple or filament yarn. They are important in the manufacture of stretch and metallic yarns and sewing threads. The different methods of core-spinning fibres Core-spun yarns be made by twisting a sheath of staple or filament yarn around a filament core made from a different fibre. Elastomeric fibre or a synthetic filament yarn is usually used as the core and synthetic or natural fibres as the sheath. Alternatively, to make a core yarn with elastane fibre, the elastane filament is stretched then covered with a sheath if non-elastic fibres. These may be natural or synthetic fibres, or a blend. The sheathed yarns are wrapped in opposite directions to balance the core-spun yarn. 1.2 Performance Characteristics of Materials Textured Yarns In their original smooth state, filament yarns have limited properties. Texturing processes add bulk and interest to yarns, making fabrics softer, more extensible, better insulators and able to retain or wick moisture away from the body. Most texturing methods depend on the thermoplastic nature of man- made fibres to heat-set permanent crinkles, creases or crimps along the length of the filaments. Textured yarn can be used in sportswear, swimwear, underwear and tights. Methods of texturing yarn False-twist texturing: smooth thermoplastic filament yarn is tightly twisted, heat-set and then untwisted. Air-jet texturing: this does not depend on thermoplastic properties so it can be used on any filament yarn. A jet of compressed air creates loops and tangles. 1.2 Performance Characteristics of Materials Fancy Yarns Fancy yarns change the appearance and handle of fabrics by adding irregularities and other effects. They are made using special spinning processes. They usually have a core, binder and effect yarn, each of which can be made out of any fibre and can be in staple or filament yarn form. Fancy yarns also provide multicolour effects by mixing fibres dyed different colours or by plying two or more different coloured yarns. Bouclé yarn: the looped yarn can add colour and give a textured bumpy feel to woven or knitted fabrics. Slub yarn: made by changing the spinning speed at irregular intervals to produce yarn with thicker and thinner sections. It gives an uneven texture similar to fabrics made from linen or wild silk. Chenille yarn: made by weaving and then cutting an open, net-type fabric into strips. Cut fibres jut out around the central core giving fabrics a fuzzy, bulky and soft appearance. Metallised yarn: gives and iridescent effect and is used to make fabrics such as lamé and brocades. 1.2 Performance Characteristics of Materials Yarn Mixtures and Blends Combining fibre properties in a yarn or a fabric makes a fabric with specific qualities required for a particular end use. Blends are achieved by spinning two or more different fibres together to make a yarn. Staple yarns require the fibres to be the same length so they can be blended together before being spun into a yarn. Continuous filament yarns can be twisted together to make a multifilament yarn, for example polyester and polyamide. The different rations of fibres to be blended are determined by the fibres used and the end product. In a yarn, a mixture usually means it contains several elements, for example core-spun yarns made from elastomerics like Lycra and many other fibre types. 1.2 Performance Characteristics of Materials The main reasons for blending yarns Performance To make fabric stronger and more abrasion resistant. Properties To make fabric easier to care for and less prone to shrinking and creasing. To give improved comfort, absorbency, thermal insulation and stretch. To give thermoplastic properties to enable heat-setting. Aesthetic Appearance To improve the texture and handle of a fabric. To give novelty effects when yarn or fabric is dyed since the uptake of dye by some fibres is better than others. To give improved colour or lustre. Additional Advantages Blending reduces costs if a cheaper fibre is included. It allows for quicker washing and drying times, which are beneficial to the environment. Disadvantages Blends like polyester/cotton burn fiercely at high temperatures and give off toxic fumes. The cotton sets alight easily, it holds the polyester in place, which then melts and drips, causing severe burns. 1.2 Performance Characteristics of Materialscharacteristics of woven fabrics Performance Woven fabrics are produced on a loom by interlacing yarns at right angles to one another: The warp yarns are fixed in the loom and run the length of the fabric. The weft yarns runs across the fabric from selvedge to selvedge. 1.2 Performance Characteristics of Materials Types of weave There are three main types of weave (plain, twill and satin) and all other weaves are variations on these types. Woven fabrics have relatively good strength and stability. The three main types of weave: Weave Main Characteristics Example Fabrics and Uses Plain (tabby) Simplest and cheapest weave. Broderie anglaise, calico, canvas, weave Has the maximum number of interlacing points chiffon, muslin, shirting, taffeta, voile, so makes a strong fabric. winceyette, chambray, flannel, Madras, Fabric has a plain, firm surface, which makes organdie, poplin. it good for printing. Typical uses: garment and interior Fabric looks the same on both sides. products, sheeting. Dyed yarns in the weave can produce a variety of decorative effects. Fancy yarns introduce interest to the fabric, e.g. bouclé fabric. Highly twisted yarns create crêpe fabric. 1.2 Performance Characteristics of Materials Weave Main Characteristics Example Fabrics and Uses Twill weave The hardest-wearing weave. Cavalry twill, denim, drill, Fabric is more complex to make, so is more expensive gabardine, tartan, dog tooth than a plain weave. check, herringbone tweeds, The interlacing of the weft and warp is offset to give a serge. diagonal pattern. Typical uses: tailored outfits More variations are possible, depending on how many or work wear. warp yarns the weft passes over. Fabric is firm but frays due to fewer interlacing points. Fabric has a definite right and wrong side The uneven surface pattern shows less dirt than other fabrics. Satin weave The warp yarn ‘floats’ over four or more weft yarns before Satin, sateen , lighter-weight going under one. satins for linings and Fabric has a right and wrong side as the weft yarns are lingerie, duchesse satin and almost completely hidden by the warp yarns. heavy bridal satins. Fabric is not hard-wearing, it frays and snags easily due Typical uses: lingerie, bridal to fewer interlacing points. weave. The use of filament yarns and longer ‘floats’ give fabrics a greater lustre. Not many variations are possible. Key term Jacquard fabrics: fabrics where the pattern is created through weaving or knitting rather than being printed onto the fabric. 1.2 Performance Characteristics of Materials Variations in weaves Weave Main Characteristics Example Fabrics and Uses Jacquard weave A computer-controlled jacquard looms lifts individual Brocade is used in formal warp yarns and interchanges plain, twill and satin weaves wear or in expensive to create complex patterns. furnishing fabrics. Brocade is a stiff, heavy fabric, it has a definite right side Damask is used in and is expensive. It has an embroidered appearance furnishing fabrics. and can include metallic yarns. Damask has a reversible embossed appearance. Warp pile Two fabrics are woven face-to-face, a knife moves back Velvet is used in garments, weave and forth to cut the third (pile) yarn and separate the two upholstery and soft fabrics. furnishing fabrics. Warp pile fabrics are difficult to work with. Fabric is expensive due to the third yarn and fabric wastage from having to use a with nap layplan. Fabric is not durable as the third yarn can easily fall away from the background weave, leaving bald patches. A heavy, warm, soft plush fabric is created with good drape but is usually dry clean only. Key term Pile weaves: classified as three-yarn system weaves as a third yarn is woven in with the warp and weft to make a fabric with a raised 1.2 Performance Characteristics of Materials Variations in weaves Weave Main Characteristics Example Fabrics and Uses Weft pile weave The cut weft loops produced during weaving create a Corduroy and needlecord are ribbed pile (cords) that runs parallel to the selvedge. used in garments, upholstery The cords vary in width, jumbo cord is very wide, and soft furnishing fabrics. needlecord is very fine. As with velvet, the fabric is expensive to produce and has similar working characteristics and challenges. Weft pile fabrics can be machine washed inside out with fastening such as zips closed. Uncut loop pile The loops are uncut making a much stronger and more Terry towelling used in durable pile weave fabric. towels and bathrobes. Fabric is expensive due to the amount of yarn used. Fabric is usually made with cotton fibres so it is soft, very absorbent and thermally insulating due to the extra yarn and loop structure. Fabric takes a long time to dry and is very heavy when wet. Fabric frays and ravels when cut, and its weight and thickness can make it challenging to work with. 1.2 Performance Characteristics of Materials Special woven effects Pattern can be introduced into woven fabric using different coloured warp and weft yarns. Stripes: two or more different blocks of colours in the warp and one colour in the weft creates stripe. Checks: blocks of different coloured dyed yarn in both the warp and the weft creates checks. Gingham: equal blocks of two different coloured yarns on both the warp and the weft give and even-sized check. Tartan: alternating different-sized bands of coloured yarn (traditionally wool) are interlaced in the warps and wefts using a plain or twill weave to create the large check pattern. Madras: commercial production is similar to tartan but brightly coloured dyed cotton yarn and a plain weave is used to create a large check pattern. 1.2 Performance Characteristics of Materials Fabric effects created using fibres and yarns Bouclé fabric: bouclé yarn creates a bulky, plain- woven fabric that can have different colours and a textured hairy, knotty surface. Bouclé fabric is made from wool or acrylic or a wool/acrylic blend. Crêpe fabric: highly twisted unbalanced yarns create a soft fabric fabric that drapes well and has an irregular crinkled appearance. A plain or special crêpe weave is used with silk, wool or polyester fibres and variations include crêpe de Chine and satin-backed crêpe. Crinkles and permanent creasing: ○ On cotton fabric, these can be achieved by printing striped pattern using a caustic soda solution, which causes the treated area to shrink and crinkle. Or, alternative blocks of tight and loose warps can be used in the loom, so that the stripes are crinkled and flat. This fabric is called seersucker. ○ If thermoplastic fibres are present in the fabric, planned or random pleats or creases can be permanently heat-set into the fabric. 1.2 Performance Characteristics of Materials Fabric effects created using fibres and yarns Crease- and shrink-resistant fabric: using thermoplastic fibres in the fabric that make it crease- and shrink-resistant. Post-weaving processes can distort a fabric, a stenter machine pulls the fabric into its intended size and shape, and heat-setting permanently holds it in place. The fabric will not shrink and will only crease if the fabric is washed at too high a temperature by the end user. Metallic effects: (we will look a this next chapter. Multi-coloured fabrics: the uptake of dyes by some fibres is better than others, so using different fibres in a fabric or different dyes make it possible to get interesting colour effects. 1.2 Performance Characteristics of Materialscharacteristics of knitted fabrics Performance Knitted fabrics are made of interlocking loops using one or more yarn. The two main types of looping are weft knit and warp knit. All other knitted fabrics are variations of these types. Knitted fabrics have fluidity, elasticity and stretch. 1.2 Performance Characteristics of Materials Types of Knit Knit Main Characteristics Example Fabrics and Uses Weft knit Simplest knit. Single jerseys (plain knit). A single yarn travels Can be produced by hand or by machine. Double jerseys (look the same on both the width of the fabric, Very stretchy and distorts easily when washed. sides). in the same way that a Drapes softly and is figure-hugging. Rib knits (used for cuffs and sweater weft yarn does in a Does not crease easily. hems). woven fabric. Each Fabric traps air and is a good insulator in still air. Sliver knits (pile-type fabric). successive row of Moving air is able to get through the gaps in the Jacquard knits (complex patterns with loops links with the fabric, making it cook to wear in these conditions. coloured yarns). previous row of loops It snags, ladders and unravels easily. Polartec fleece (brushed weft-knitted fabric in the fabric. Has a definite right and wrong side. with an extra yarn knitted in to trap air and Is used to create tubular fabrics for seamless give a soft dense nap). garments. Typical uses: wide range of garments and socks. Warp Knit More complex structure. Tricots (used in lingerie). Individual yarns are Can only be produced by machine. Locknit fabrics (used in swimwear, hosiery interlocked sideways Less stretchy, gives a firmer fabric. and garments). along the length of the Does not ladder or unravel so can be cut and Knitted velour (similar handle and fabric in the same way sewn more easily. appearance to velvet but stretchy). that the warp yarn Faster than weft knitting. Raschel knits (resemble crocheted, lace runs parallel to the Cheapest and fastest method of fabric net or mesh fabrics). selvedge of a woven production using yarns. Knitted lace fabrics (used in garments and fabric. Each needle A wider variety of knits can be produced. curtains). loops its own yarn. Typical uses: geotexttiles and biotextiles. 1.2 Performance Characteristics of Materials Hand- and machine-knitted methods Hand knitting: has a craft aesthetic and is used to make individual products. Traditional styles of hand knitting include Aran (cable and lattice patterns), Fair Isle (multi-coloured patterns) and Guernsey (cable knit). Machine knitting: can be done on flat or circular industrial knitting machines. Flatbed machines have a row of needles that produce a wide width of fabric. Circular machines make a tube of knitting. Panel Knitting (pieces with integral welts): individual, flat, rectangular panels including a finished- off edge for the cuff or waistband, are knitted. The garment parts are then cut to shape and assembled. Fully fashioned panels: the garment parts are knitted to the required shape and size and then stitched together to make the garment. This process is used to manufacture high-quality garments and hand-knitted garments. Whole garment knitting: knits a garment three- dimensionally in one piece. Is is more sustainable as there is waste and the seamfree garments don’t break a garment’s flow, making them comfortable to wear and easier to move in. They are used in sports, 1.2 Performance Characteristics of Materialscharacteristics of non-woven fabrics Performance Non-woven fabrics are produced directly from fibres. They include felts and bonded fabrics. The process used depends on fibre type and the end- use requirements. The absence of yarn means felted fabrics lack strength and are difficult to maintain. Non-woven fabrics can be made in a range of weights, they are stiff, have no stretch and do not drape well. They do not fray, and cut easily with scissors or a laser. They are cheap to produce, making them suitable for disposable or one- use products. They have no grain, so a layplan is not needed, making them economical in use. The fibre webs are good thermal insulators, they also absorb sound and can be made flame retardant. Non-woven fabrics can be moulded into shapes. Some non-woven fabrics can be recycled and some can be made from recycled fibres. Key term Non-woven fabric: made directly from 1.2 Performance Characteristics of Materials Production methods of non-woven fabrics 1.2 Performance Characteristics of Materials Smart Materials Smart materials are able to react to external stimuli or changes in their environment without human intervention. They revert to their original state once the stimuli have been removed. External stimuli include changes in temperature, light levels and pressure (force). Smart materials include ones that: Monitor body functions and administer medicines or give warnings, for example Mamagoose baby monitoring pyjamas. Maintain a personal microclimate, for example Stomatex, Outlast. Have chromatic properties and change colour in response to specific situations, for example heat sensitive bandages that indicate infection. Have shape memory, for example Corpo Nove shirts, which adjust to differing temperatures. Are self-cleaning, for example nano-technology fabrics triggered by sunlight. Can generate solar power when exposed to sunlight. Key term Smart material: a material that is able to react to external stimuli or changes in its environment without human intervention. 1.2 Performance Characteristics of Materials Technical Textiles Technical textiles are manufactured for non-aesthetic purposes where function is the primary criterios. They are new materials that have been developed from their original form. Technical and modern materials include the following examples: Gore-Tex Kevlar and Nomex Phosphorescent textiles, for example high-visibility safety clothing and novelty clothing. Textiles finished with phosphorescent dyes glow in the dark. The pigment is able to absorb light energy, store it and later emit it. Reflective textiles using glass beads, for example 3M Scotchlite reflective material. Microencapsulated fibres, for example those that release scents or beneficial chemicals by sensory perception technology, such as moisturising tights. The chemicals are incorporated into the core of core- spun microfibre yarn. Microfibres, Key terms for example Tactel Aquator, Tactel Diablo and Trevira Finesse. Technical/modern materials: new materials that have been developed from their original form. Microencapsulated fibre: a microfibre that has tiny capsules containing health or cosmetic chemicals embedded into its hollow centre. 1.2 Performance Characteristics of Materials Materials using Nano-Technology Ceramic and carbon fibres are important in the production of nano-fibres because they are extremely lightweight and very strong. The tiny fibres are made using an electro-spinning process, and are collected in the form of sheets that resemble non-woven felt. These sheets of fabric can be used as breathable membranes. Carbon fibres are used to make intelligent fabrics or wearable computers. Key terms Nano-fibre: an extremely lightweight strong fibre that is less than one micron in diameter. 1.2 Performance Characteristics of MaterialsCharacteristics of Fabrics Performance The interrelationship between the following factors determines the overall performance characteristics of a fabric: The fibre, or blend or mixture of fibres used The yarn structure (not applicable in non-woven fabrics) The way the fibres or yarns are incorporated to construct the fabric The way the fabric is finished The end use determines what performance characteristics are required in a fabric. Fundamental performance characteristics include: strength, durability, elasticity, flammability, thermal qualities, absorption, water resistance, formability, handle, drape, weight and rip-proofing. Key terms Formability: the ability to manipulate and shape fabrics without damaging them. Weight: the outcome of how a fabric has been woven, its finish and sometimes the fibre type. Rip-proofing/rip-stop fabric: has a distinctive woven-in raised square pattern that stops the fabric from ripping or tearing. 1.2 Performance Characteristics of Materials Colour, repeat pattern, directional pile, nap, texture and lustre are additional features that can influence the sales potential of a fabric. Key terms Repeat pattern: the distance between one point of a design and the exact point where it begins again. Directional pile: the raised surface on a fabric that appears to change colour when viewed from different angles.