1.2 - fibres Flashcards
Understand performance characteristics of fibres
properties of cotton
this about: elasticity, absorbency, breathability, strength, flammability, insulation, static, handle, damages, environment
- naturally breathable as it conducts heat away from the body
- very adsorbent
- non-static as moisture is present
- good strength due to natural twist
- little elasticity, creases easily
- highly flammable
- poor insulator
- comfort and soft handle
- damaged by mildew, prolonged sunlight exposure
- biodegradable
examples of cotton
calico, muslin, flannel, denim, gingham, madras, corduroy, velvet, knitted jersey
terry towelling, voile, winceyette, chambray, poplin, drill, seersucker, velour
uses of cotton
- apparel fabrics e.g shirts, dresses, jeans, underwear, socks, uniform
- home textiles: towels, sheeting, curtains, soft furnishings, throws
- commercial textiles: medical dressings, nappies, sewing threads, ropes
- leisure textiles: tents, awnings, boat sails, bags, sportswear
- blended and mixed, usually with polyester, wool and elastane
draw the cross section of cotton
refer to class notes
cotton fibre production
- grows in a boll around the seeds of cotton plants
- harvesting is carried out by hand or using a picking machine
- fibres are separated from seeds using a process called ginning
- mechanical purification is used to remove foreign matter
- fibres are sourced to remove the natural wax coating from surface of fibres
- processed cotton fibres are spun into staple yarn fibres
what is cotton
- the most widely used natural plant/cellulose fibre
- comes from the seed fibre found in the cotton bolls of the cotton plant
what is linen
- most expensive natural fibre
- labour intensive to product so produced in small quantities
- comes from the bast fibre of the flax plant system
properties of linen
- highly absorbent, naturally breathable
- very strong due to the longer length of the staple fibres
- poor elasticity, creases easily
- highly flammable
- poor insulator
- flat surfact reflects light, subtle lustre
- poor drape and stiff handle
- damanged by midlew, sweat and bleach
- biodegradable
examples of linen
crash, duck, huckaback, interlining, Holland, union (half linen - fabric has cotton warp yarns and linen weft
uses of linen
- apparel fabrics: summer or tropical garments
- home textiles: tablecloths, dish towels, bedsheets, curtains
- commercial textiles: lace trimmings, ropes, taurpaulins, sewing thread
- leisure textiles: awnings, art canvases
- blended and mixed, usually with cotton
draw the linen fibre cross section
refer to class notes
linen fibre production
- fibres are loosened from the flax plant stems using a process called retting
- 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
what is ramie
- one of the oldest natural fibres
- high cost of fibre extraction and production reduces its competiveness, however consumer demand for sustainable fibres is leading to increased use
- ramie fibres can be harvested from the same plant up to 3 times a year, making it a highly sustainable fibre source
properties of ramie
- good absorbency, breathable
- keeps its shape and does not shrink
- harder to dye than cotton
- naturally white in colour
- has good strength
- poor elasticity, creases easily
- highly flammable
- poor insulator, cool to wear
- smooth lustrous appearance
- stiff and brittle handle
- resistance to mildew, light and insect attack
- biodegradable
examples of ramie
ramie
uses of ramie
- apparel fabrics: lightweight summer use
- home textiles: table linens, dish cloths
- commercial textiles: ribbon, sewing thread, sacks, twine and cord
- mostly blended with cotton, wool, polyester or acrylic
ramie fibre production
- 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
draw the cross section of ramie
refer to notes/internet
what is 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 of wool
- water-repellant and excellent moisture absorption
- anti-static as moisture is always present
- heat, moisture and mechanical action shrink and felt the fibres, making wool difficult to care for
- adequate strength but not very durable
- high natural fibre restistance, self extinguishes if set alight
- excellent elasticity, the natural crimp provides ‘springiness’, enabling creases to fall out
- good insulation/thermal qualities
- no lustre because fibres are not smooth
- origin, fineness and length of fibre determine the handle of wool fabrics
- wool can be soft or itchy
- biodegradable
examples of wool
worsted, baize, flannel, jersey, tweed, serge, fleece, tartan
uses of wool
- apparel fabrics: coats, suits, trousers, sweaters. hats. scarves, gloves, socks
- home textiles: blankets, textiles
- commercial textiles: loft insulation, noise insulation
- leisure textiles: horse rugs, athletics and leisure wear
- blended and mixed, usually with cotton, silk, polyester, acrylic and other animal hair fibres
- sportswear is a mix of merino wool and polyester fibres
- the wool draws moisture away from the body which is wicked away by the polyester, keeping the wearer cool
draw the wool fibre structure
refer to class notes
wool fibre production
- Shearing: the sheeps fleece is removed by hand typically one a year
- Sorting: the sheeps longer fibres are separated from the shorter fibres.
- 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.
- Spinning: the rovings are fed into a mechanised spinning machine and a predetermined amount of twist is applied. The yarn is re-wound into suitable packages for knitting and weaving
what happens to the sheeps longer fibres vs the shorter fibres after sorting?
the worsted system to make high end products such as suits
- the shorter fibres are processed through woollen system to make products such as blankets and sweaters
What happens to the sliver after carding?
Sliver is processed further using a roving machine to compact and hold the fibres closer together, minimising the chance of breakage during spinning.
what are animal hair fabrics?
- luxurious animal fibres are expensive due to the limited supply
- they include cashmere, from undercoat of cashmere goats
- mohair, from angora goats
- angora, from angora rabbits
properties of animal hair
- similar qualities to wool fibres
- naturally fire resistant
- very good thermal insulators
- soft, luxurious handle and appearance
- biodegradable
examples of animal hair fabrics
- cashmere: soft fibres, lightweight, lustrous, three times more insulating than wool
- mohair fibres: long, lightly curled, silky lustre, naturally elastic, crease resistant, dye well
- angora fibres: very fine and lightweight, hollow core makes fibres good at absorbing moisture vapour
uses of animal hair
- apparel fabrics: luxury coats, suits, knitwear, shawls
- home textiles: luxury interior textiles
- can be used alone or blended with wool to reduce cost
animal hair fibre production
- with angora and cashmere, fibres need to be washed and de-haired to remove the coarse guard hairs before being spun into yarn
- angora goats are shorn twice a year to collect the mohair fibres. Fibres are processed in a similar way to wool fibre but 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 textiles industry
- other examples include: camel, alpaca, vicuna, and horsehair
what is cultivated silk?
- cultivated silk comes from the cocoon of the Bonbyx mori silkworm
why is cultivated silk considered unethical?
- 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
what is wild silk?
- production of wild silk is on a smaller scale than cultivated silk
- wild silk comes from the cocoon of other species, e.g 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 filament
- wild silks tend to be more difficult to unravel as the cocoon has been damaged
properties of silk
- excellent tensile strength due to long continuous length of the fibre
- very absorbent
- anti-static as moisture is always present
- weak when wet, so hard to care for
- extensible and elastic
- does not burn easily, self extinguishes
- cool and warm
- naturally lustrous
- pleasant handle and comfortable to wear
- has fluidity and drapes well
- weakened if exposed to sunlight and sweat
- biodegradable
examples of silk
- crêpe de Chine, organza, bourette, wilk silk (tussahn Honan, shantung), satin crêpe
- duchesse, habutai, pongee, taffeta
uses of silk
- apparel fabrics: formal wear, ties, lingerie, scarves
- home textiles: wall hangings
- commercial textiles: surgical sutures, sewing and embroidery threads, ribbons
- blended as a staple fibre with wool
draw the silk fibre cross-section
refer to class notes
silk fibre production
- silk worm 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 creates a cocoon when wound around the body of a silkworm
- to extract the fibre, cocoones are degummed by soaking them in boiling water. kills moths and softens 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
process of silk in brief
adult moth -> eggs -> caterpillars -? boiling of cocoon to kill pupae -> reeling silk fillament
first generation fibres
not sustainable
- acetate - cotton fibre waste is dissolved into a polymer solution by treating it with a solvent
- viscose - wood pulp is dissolved into a polymer solution by treating it with a solvent
acetate production
- acetate - dry spinning: the polymer solution is extruded into a stream of warm air, which evaporates the solvent and solidifies the filament fibres
viscose production
- viscose - wet spinning: the polymer is extruded into a chemical bath. different chemicals are used to make viscose compared to modal which also uses this technique.
- the chemicals neutralise the solvent and solidify the cellulose from the wood pulp into filament fibres
modal production
- modal - wet spinning: the polymer is extruded into a chemical bath. different chemicals are used to make modal compared to viscose which also uses this technique.
- the chemicals neutralise the solvent and solidify the cellulose from the wood pulp into filament fibres
Lyocell (tencel)
close loop system: cellulose from the wood pulp is regenerated in a similar way to wet spinning but water is used to wash and remove the solvent.
- the water and solvent are recovered and recycled for use within a closed-loop system
new generation fibres
sustainable
- modal: wood pulp from sustainable managed forests is dissolved into a polymer solution using a solvent
- Lyocell: wood pulp from sustainable managed forests is dissolved using a solvent
what are manufactured regenerated fibres?
made from natural cellulose that has been chemically modified.
- other examples include cupro, alginate and rubber
properties of regenerated fibres and their uses part 1
- structure allows similar or better levels of absorbency than cotton
- shape can be changed using spinnerets with different cross-sections
- take dye and print techniques especially well
- non-static as some moisture is always present
- easy care, but first generation fibres should not be tumble dried as they are prone to shrinking
- naturally breathable with good wicking properties
properties of regenerated fibres part 2
- 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 recyclabl, inexpensive to produce
uses of regenerated fibres
- fashion garments, lining fabric, lingerie, trims and ribbons
- can be used in their filament form or cut up and used as staple fibres
- used in blends with natural fibres or on their own because of their reduced environmental impact
draw the cross section of viscose
refer to class notes
first generation fibres
viscose
- more absorbent than cotton and other regenerated fibres
Acetate
- lower absorbency, prone to static
- more elastic than others but still creases
- thermoplastic capabilities
- subdued lustre and elegant drape
new generation fibres
modal
- stretched more than viscose after spinning to make fibres stronger. can be tumble dried
- silky smooth, very soft handle and drape
Lyocell (tencell is trade name for lyocell)
- stronger and more extensible than cotton so does not crease as much
- totally biodegradable, recyclable and made using a closed-loop system that reduces the chemicals used in the manufacturing process
synthetics general characteristics
- 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
how does melt spinning of synthetic fibres work?
- polymer chips -> molten polymer
- goes through metering pump and spinnere
- air flow hardens molten polymer
- through a take up then drawing and winding
synthetic fibre cross section
refer to class notes
what is polyamide (nylon)?
- produced as continuous smooth filaments including very fine microfibres
- they can be textured or cut into staple fibres
- microfibre brand names include:
-> Tactel Aquator, wicks moisture away from the body, used for underwear and sportswear fabric
-> Tactel Diablo, lustrous fabric with drape used to hosiery and lingerie
properties of polyamide (nylon) part 1
- low absorbency, dries quickly, does not shrink, prone to static
- very strong and durable, high abrasion resistance
- good elasticity and crease recovery
- low flammability, fabric melts and drips
- thermoplastic, fibres can be textured, desired creases can be heat-set or inadvertently added to fabric if washed at too high a temperature
properties of polyamide (nylon) part 2
- lightweight and can have lustre if the fibres are extruded as flat smooth surfaces reflecting a lot of light
- cross-section shape and fibre thicknesscan be engineered to provide fine, smooth, soft fabrics 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
uses of polyamid (nylon)
- clothing, tights, socks, underwear
- outdooer and active wear
- tents, umbrellas, carpets
- in staple form, it is blended with most fibres
what is an aramid?
- technical textiles developed from polyamide, brand names include:
- kevlar, Nomex
properties of an aramid
greater strength and durability, stab and tear resistant, fine and lightweight, flexible for easy of movement
- nomex has similar properties to kevlar and can withstand even higher temperatures
uses of aramid
- bullet and stab proof vests
- motor sport clothing
- industrial work wear
what is polyester?
- produced as continuous smooth filaments
- they can be texture or cut into staple fibres
- microfribre trade name: Trevira Finesse
properties of polyester
- very similar properties to polyamide
- the most commonly used synthetic fibre
- better thermoplasticity qualities than polyamide
- does not weaken in sunlight
- non-renewable source but can be recycled e.g Polartec fleece can be made from recycled drinks bottles
uses of polyester
- a wider range of clothing, including outdor and active wear
- bed sheeting, lining fabric
- sewing thread
- wadding and fibre fill
what is acrylic?
spun using the wet or dry spinning method. mostly used as bulky staple fibres
properties of acrylic
- low absorbency
- prone to static
- easy care, dries quickly
- good strength
- sensitive to heat and highly flammable
- good elasticity, crease resistant
- good thermal qualities, soft and warm
- wool-like handle, good drape
- poor lustre
uses of acrylic
- knitting yarn, knitwear
- fake fur, carpet
- soft furnishing fabrics
- blended with wool or polyester
what are chlorofibres (polyvinyl)
used in filament or staple form or as a coating.
properties of chlorofibres
- strong and durable
- breathable, easy care, waterproof
- good insulator
- PVC can be recycled
uses of chlorofibres
- raincoats, showerproof coatings
- thermal clothing
- active sportswear
- socks and underwear
what are fluorofibres (PTFE)
used mainly as a coating
- trade name: Teflon
properties of fluorofibres (PTFE)
when applied to fabric as a finishing process, the fabric is:
- water repellent and stain resistant
- easy care and less energy needed to dry fabric
- durable and flexible
- breathable but windproof
uses of fluorofibres
used to protect fabrics
- school trousers, workwear, soft furnishings, shoes
what is elastomeric (elastane)
always used as the core in core-spun yarn combined with natural and synthetic fibres
- brand name: Lycra
properties of elastomreric
- low absorbency and easy care
- good water resistance and durability
- very fine and lightweight
- gives a high degree of comfort and allows free movement
- increases shape retention, crease recovery and improves draper in woven fabrics
uses of elastomeric fibres
- 1-2% in socks or trousers
- 15-20% as needed in swimwear, foundation wear or sportswear
inorganic fibres
inorganic fibres are not synthetic polymers but are included in the man-made fibre classification
what is glass (fibreglass) and how is it processed?
- source: powdered mineral compounds
- a direct melt method is used to draw filament glass fibres from the molten mineral compound
- the fibres can be used as filaments or cut into staple fibres
properties of glass fibres
- high tensile strength but low extensibility
- poor abrasion resistance
- high heat resistance and thermal conductivity
- impermeable and unaffected by sunlight, chemicals and microorganism attack
- non-stick, non-toxic and reflective
uses of glass fibres
- insulation material in buildings
- flame-retardant fabrics e.g theatre safety curtains, strengthened glass
- reinforced plastics, hospital wall coverings
what is carbon (graphite fibre) and how is it processed>
- source: carbon created by burning acrylic fibre
- carbon fibres are twisted togeether to form a yarn that can be used by itself or made into a fabric
properties of carbon fibres
- very strong for its size
- lightweight
- abrasion and tear resistant
- flame resistant at very high temperatures
- resistant to chemicals
uses of carbon fibres
- protective clothing
- intelligent electro-conductive fabrics for e-textiles
- aeroplane interiors e.g carpets, upholstery fabric, production of nano-fibres
what are metal fibres and how is it processed?
- source: copper, aluminium and steel for common uses
- titanium, gold and silver for special uses
- very thin layers of metal are laminated between clear film and cut lengthwise into thin strips
- alternatively, the metal is heated until it vaporises and deposits at high pressure onto polyester fibres
properties of metal fibres
- strong and abrasion resistant
- lightweight
- withstands high temperatures
- good conductor of heat and electricity
- anti-bacterial and anti-microbial
- anti-static
- stiff handle and high lustre
uses of metal fibres
- decorative fabrics and trime e.g: Lurex
- silver prevents a build-up of bacteria in sports clothing and medical applications
- conductive sewing thread in e-textiles
what are ceramic fibres and how are they processed?
- source: powdered inorganic non-metallic maaterials such as crystallines oxide
- carbon and silicone are also considered ceramics
- processing: incorported into synthetic fibres by coating them with ceramic particles or encapsulating them in the fibre
properties of ceramic fibres
- resistant to up to 1000 degrees celcius temperatures
- lightweight and resistant to chemicals
- produces fabrics with UV protection
- has heat deflection properties to regulate body temperature e.g protective ceramic coating material (PCCM)
- has therapeutic properties if combined with body heat
uses of ceramic fibres
- industrial work wear
- swimwear e.g Esmo and Sunfit fabrics
- a fabrics surface coated with PCCM deflects heat in hot weather
- when applied to lining fabrics, it deflects body heat back to the body
- bioceramic fabric e.g Under Armour Athlete recover sleep wear
- production of nano=fibres
- thermolite, a lightweight fibre with a hollow core used in socks, sleeping bags and jackets
