Breakdown Section A - Walton High School

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SECTION A: MATERIALS AND COMPONENTS
Fibre Classification and Generic Names
All fibres are made from Polymers a generic name for a long chain of molecules. Fibres can
be natural polymers or synthetic polymers
Natural Fibres:
Cellulosic (plant):
Cotton – staple fibre, absorbent, breathable, soft handle, strong,
creases easily
Linen – staple fibre, creases badly, absorbent but dries quick, crisp
handle, dirt-repellent
Ramie – staple fibre, highly absorbent, strong, stronger when wet, gets
smoother when washed, low abrasion resistance, creases easily,
stiff/brittle handle, expensive
Other non-traditional plant fibre sources are :
Bast fibres (from stem plant) such as Hemp
Leaf fibres such as Sisal, Pinepple, Banana
Seed fibres such as Coir
(See chapter 2 of RH)
Protein (animal):
Wool – staple fibre, hydrophillic (can absorb without feeling wet),
also hydrophopic (repels raindrops), fire-resistant, crease resistant,
feels warm due to the scales on surface of fibre that trap air
Silk – filament fibre, smooth, lustrous, strong, absorbent, cool but also
good insulator. Can be the cultivated variety which is smoother or wild
variety which is coarse and ‘rustic’ looking (like silk dupion).
Other non-traditional animal fibre sources are:
Hair – Cashmere and Mohair from goats,
Angora from rabbits,
Llama fibre,
Vicuna from camels
Mineral:
Asbestos – non-flammable, resistant to chemicals, was used where
heat protection was required e.g. theatre curtains, not clothing. Now
restricted due to health hazard
Manufactured Fibres: (all made as filament but can be cut into staple)
Regenerated
Cellulosic:
(from natural cellulose
found in wood pulp,
dissolved in chemicals
and extruded through a
spinneret)
Viscose- highly absorbent, soft, comfortable, good drape, not
strong, creases easily
Modal – often blended, highly absorbent, smooth, good drape,
not durable or strong, creases easily, low shrinkage
Lyocell – branded as Tencel, like cotton but very eco-friendly,
high strength, absorbent, breathable, low shrinkage
Cupro- breathes like cotton, drapes beautifully, and feels like silk
on your skin. An elegant fabric
Acetate- low absorbency, low warmth, fast drying, soft handle,
smooth, drapes well, creases easily, not strong
Tri-acetate- similar to above but even less absorbent, softens at
high temperature so can be heat set into pleats etc
Rubber- stretchy, non-slip, can be printed onto parts of garment
(like soles of slipper socks)
Alginate- from seaweed, healing properties so is used for
medical textiles
Synthetic:
(formed entirely from
petro-chemicals made in
liquid form then extruded
through a spinneret )
Polyamide – known as Nylon, non-absorbent, prone to static,
very strong, very durable, easy care, dries quickly, crease
resistant, melts with heat
Acrylic- soft, wool-like, warm, fast-drying, strong, crease-resistant
Polyester-low absorbency, fast-drying, strong, crease-resistanct
Elastomeric/Elastane- branded as Lycra, always blended, adds
stretch/comfort, crease resistant
Flurofibres (PTFE) – used as a protective coating on fabrics,
water repellent, stain resistant, flexible, durable, used in Goretex
Chlorofibres(PVC)- can be used as a protective coating on
fabrics, waterproof, strong, durable, always blended
Polyolefines (polypropylene)- not used for clothing, low melting
point, high strength, non-absorbent, crease resistant, used for
carpet backing, sacks, webbing, geo-textiles
Aramid fibres-group of high performance fibres that include
brand names such as; Nomex which is flame resistant, used in
fire-fighters uniforms, and Kevlar which is extremely high
strength, used in bullet-proof vests
NOTE: Microfibres
these are very fine
synthetic fibres (around
60 times finer than
human hair) made from
polyamide or polyester.
When made into a fabric
it has a peach-like touch,
excellent draping
qualities and good
strength. Now being
used in smart fabrics and
high performance active
wear.
Inorganic:
Glass fibre- strong, shatterproof, non-stick, non-toxic, used in
aerospace and military, flame and heat barriers, protective
garments
Carbon fibre-strong, lightweight, flame resistant, used for
transport upholstery, rocket motors, protective clothing for military
Metallic fibre- aluminium, copper, steel, gold used in decorative
textiles, silver used for anti-bacterial, can be used in protective
garments
Ceramic fibre- can regulate body temperature, resistant to high
temperatures, used in swim-wear, UV protective clothing,
industrial work wear
Shape and formation of
fibres:
Fibres come from a variety of different sources, the way that they
are formed (whether naturally or man-made) will affect the
properties that they have. E.g. wool fibres naturally have scales
that trap air so are warm. Synthetic fibres are produced by
extruding the liquid polymer solution through a spinneret into
either; warm air (dry spinning), cold air (melt spinning) or fluid
(wet spinning) resulting long smooth continuous filament fibres.
Commercial Names
of Fibres and Fabrics
Tactel – polyamide based Microfibre, very lightweight, soft, dries
quickly, used in Marks & Spencer lingerie and fashion items
Tencel- brand name of the Lyocell fibre
Lyocell- regenerated cellulosic fibre
Lycra- brand name of an elastane fibre
Polar fleece- synthetic pile fabric originally made by Polartec
Trevira- flame retardant polyester fibre
Gore-Tex- a breathable, yet waterproof 3-layered fabric
Fibre brand promotion:
e.g. the use of swing tags that give information about the fibre
properties and include logos and slogans to promote brand
awareness and give the consumer a sense of quality in the
product.
YARNS
(defined as a fine
continuous length of
fibres with or without
twist)
Yarn types:
Carding-fibres are detangled and made to lie in the same direction
Spinning- fibres are drawn out and twisted together
Twist direction- fibres are twisted together to make them
stronger, the twist direction can be clockwise (‘Z’ twist) or anticlockwise (‘S’ twist). Light is reflected in opposite directions by
these 2 types of yarns. Different effects can be given to fabric
using S and Z twist yarns.
Twist level- the number of turns per metre, i.e. how tightly the
yarn is twisted. Low twist yarns are softer, weaker and bulkier.
High twist yarns are stronger and harder.
Tex and Denier - the systems used to measure the size of yarns
and fibres, both in thickness and weight (e.g. as seen on tights)
Spun yarn- this is made from staple fibres
Filament yarn- made from continuous filament fibres, can be
monofilament (a single filament) or multi-filament.
Single yarn- this is one thread of spun yarn or continuous
filament fibres, can be a blend of 2 or more fibres
Plied yarn- 2 or more single yarns are twisted together for a
thicker, stronger yarn, e.g. 2 ply, 3 ply yarn.
Cabled yarn- 2 or more plied yarns are twisted together – a bit
like a rope or a cable
Core-spun yarn- the yarn has a core that stays central and other
staple fibre yarns are spun around it (elastane/Lycra)
Fancy yarn- spun to give irregularities such as colour effects or to
give interest to the fabric i.e. slub (lumpy yarn), loop, chenille
(hairy yarn) or boucle (curly yarn)
Bulked yarn- treated so that they have increased fluffiness and
bulk
Textured yarn- synthetic thermoplastic yarns that have been heat
processed to have crimps, coils or loops along the length.
FABRIC
CONSTRUCTION
METHODS
Woven:
Plain- most common, strong, firm, hardwearing, variation can be
achieved through use of thick/thin/coloured/fancy yarns or by
tightness or looseness of weave
Twill- produces diagonal lines across the fabric (e.g. denim)
drapes well, strong, firm, hard-wearing
Satin- is warp-faced (the warp yarns ‘float’ over the weft yarns)
giving a smooth surface, drapes well. Sateen weave is a weftfaced variation
Brocade- a richly decorative weave in which an extra weft yarn
creates an ornamental pattern
Jacquard- woven on an automated Jacquard Loom, a
complicated large scale repeat pattern design in 3 or more
colours
Pile weave- can be knitted or woven, has a raised surface effect,
formed by tufts or loops that stand up from the fabric, e.g. velvet,
corduroy or towelling
Double cloth- two separate fabric layers are woven at the same
time on one loom, held together by interlocking weft or warp
yarns, used for heavy luxury coats or blankets
Pique- has a dimpled surface effect, used for polo-shirts and
sportswear
Special woven effects:
Stripes and checks- created using coloured warp and/or or weft
threads
Tartan- originally a twill weave woollen cloth, with checks created
by coloured warp and weft.
Madras- is a light cotton colourful checked fabric that is typically
associated with summer clothing
Crepe- has a crinkled or puckered surface, can be achieved
through mixing ‘S’ twist and ‘Z’ twist yarns or by chemical
treatment
Cultural woven
traditions:
Ashanti strip weaving- made in West Africa, cloth is handwoven in several long, narrow bands then sewn together side by
side to make one large piece of cloth Special weaving or dyeing
techniques may be used to add patterns, textures, and colours to
the strips.
Back strap looms- used in parts of South America. The
backstrap loom is portable it is tied to a post or tree at one end
and has a strap at the other end that is placed around the
weaver’s waist as they sit on the ground or small stool and
weaves.
Ikat weaving- created by dyeing the warp threads before they are
attached to the loom. The threads are arranged into bundles,
each bundle is tied and dyed separately, so that a pattern will
emerge when the loom is set up.The tightly bound bundles are
sometimes covered with wax that will keep the dyes from
penetrating.
Knitted:
(weft)
Weft knit-made from a single yarn which is fed across the width
of the fabric, stretchy, may ladder, has right and wrong side, can
be hand-knitted or on computer controlled knitting machines
Single jersey- weft knitted fabric, stretchy, face and reverse sides
appear different, tendency to curl at edges, produced on one set
of needles, used for t-shirts, jumpers and underwear etc.
Double jersey- weft knitted fabric made on two sets of needles,
fabric is more compact and stable than single jersey, not as
stretchy, face and reverse side look the same, used for t-shirts,
leggings, skirts and sportswear.
Rib knit- weft-knitted fabric with vertical lines, is very stretchy
widthways, suitable for jumpers, socks, also used at cuffs and
hem of jumpers
Jacquard knit-has a patterned design in three or more colours,
knitted on a computer controlled knitting machine. Not very
stretchy
Knitted:
(warp)
Warp knit- made from lots of separate yarns, loops interlock
vertically, stretchy but do not ladder, can’t be unravelled, always
made on knitting machine.
Tricot- a warp-knitted fabric made from 2 sets of warp threads,
has a soft handle, good drape and stretch, often used for lingerie
and gloves
Velour- warp-knitted pile fabric made from continuous filament
fibres, has a raised fleecy surface effect
Locknit- is a combination of tricot and plain knit stitches, made
from filament yarns. Locknit fabric is lustrous and is used for
underwear and linings.
Raschel lace- knitted lacy fabric usually from polyester, has loops
Net- or netting is any textile in which the warp and weft yarns are
looped or knotted at their intersections, resulting in a fabric with
large open spaces between the yarns.
Knitting manufacture:
Hand-knitting- weft knitted fabric produced by hand using 2
knitting needles, yarns are looped through each other, used for
one-off pieces or craft items.
Machine-knitting- computer controlled knitting machine, either
circular (produces tubes) or flat-bed machines
Panel knitting- knitted fabric is produced in individual panels of a
width to suit the end product, this type of knitting produces some
wastage
Fully fashioned panels- individual parts of a product are knitted
to shape so they can be sewn together to make the product
without cutting the fabric, this method reduces waste.
Whole garment knitting-or 3D knitting, this is when a whole
product is knitted as one-piece, incorporating all the garment
shaping, there is minimal sewing necessary and no fabric waste.
Non-Woven:
(made directly from
fibres, they miss out the
yarn stage)
Felting- can be wool felted or needle felted, wool felt is when
the wool and other fibres are matted together by moisture, friction
and heat. Needle felt is generally made with synthetic fibres, they
are matted together by barbed needles that entangle the fibres.
Bonding-a web of fibres are bonded together with either;
adhesive, heat or solvent
Lamination- a laminated fabric has 2 or more textile layers that
are joined by adhesive or heat, e.g. when iron-on interfacing is
added to a whole piece of fabric
Stitch bonded- when 2 or more layers of fabric are stitched
together over the surface, e.g. quilted fabric
Open work fabric:
Lace- fine open fabric of mesh or net, usually decoratively
patterned
Leno- an open, loosely woven fabric that uses crossed warp
threads to make square looking holes in the fabric
Crochet- hand or machine made chain of loops produced from a
single thread using a hook
Macramé- decoratively knotted string or yarn
New Technology:
Smart materials- a fabric that reacts to external stimuli, e.g.
changes colour with heat etc.
Microfibres- these are very fine synthetic fibres (around 60 times
finer than human hair) made from polyamide or polyester. When
made into fabric it has a peach-like touch, excellent draping
qualities and good strength. Now being used in smart fabrics and
high performance activewear.
Breathable membranes- a fine layer of fabric that has micro
holes that allow perspiration to pass through but are too small for
raindrops to penetrate, e.g. Goretex
Fabric Finishes
(a finish is added to cloth
to enhance the
properties, finishes can
be Physical i.e. put
through a mechanical
machine; or Chemical,
i.e. when the fabric is
coated with a resin
Physical finishes:
Brushing- the fabric is passed through rollers covered with wire
brushes that ‘fluff’ up the surface of the fabric. The raised surface
is called a nap, e,g. brushed cotton used for shirts
Calendering- the fabric is passed through heated heavy rollers
under pressure to smooth the surface and add shine (like heavy
ironing) the rollers can have a pattern on them, this would
produce an embossed fabric
Chemical finishes: a polymer resin is applied to the back or the
face side of a fabric to provide enhanced properties such as;
Flame-resistance (Proban),
Water-resistance (Teflon or Scotchguard),
Crease-resistance
Stain resistance (Teflon or Scotchguard),
Shrink resistance
Heat setting-a resin is applied to fabric, it is then pressed into
pleats then heat cured so that they are permanent
SURFACE
DECORATION
Dyeing:
(adding or changing the
colour of the fabric)
Domestic- putting the fabric in a solution of coloured dye and
water, usually required heat and salt to set the dye so it will not
wash out (make it colourfast)
Industrial – when fabric is dyed in large quantities it is passed
through a bath or vat of dyestuff and then squeezed between
rubber rollers to ensure even and consistent dyeing across the
fabric
Discharge- colour is changed by removing the dye from the
fabric, i.e. with bleach.
Resist- parts of the fabric are tied-up or covered with wax before
dyeing to stop the dye reaching the fabric, causing un-dyed
patterns to emerge
Stages when dyed- textiles can be dyed at the fibre, yarn or
fabric stage of manufacture, eg, striped or checked fabrics would
use dyed yarns. Cloth is often produced in a greige (un-dyed)
stage then piece dyed to suit requirements. Whole garments
dyeing enables colours to be chosen late in the manufacturing
stage as dictated by fashion.
Colourfastness- resistance to colour loss during use or washing.
Fastness depends of the type of dye and the fabric
Printing:
Screen Printing- fabric is held firm and flat, a patterned mesh
screen is positioned on the fabric and a squeegee forces the
printing paste through the mesh screen onto the fabric
Rotary Screen Printing-the printing ink is applied to the fabric
from inside a pattered mesh roller, this method is suitable for
continuous production and is very fast.
Transfer- the pattern is first printed onto special paper an then
transferred onto the fabric using heat and pressure
Ink jet- digital printers print CAD designs directly onto the fabric
using special inks
Embroidery:
Machine Embroidery- stitches worked by computer controlled
machines, used in industrial manufacture for logos or
embroidered fabric
Hand Embroidery- decorative stitches worked by hand, used for
one-off products or craft items
Quilting:
Usually 3 layers of fabric; a stable backing fabric, a layer of
wadding and a decorative top fabric (often satin) these are
stitched together through all 3 layers in lines or decorative
patterns, used to add warmth and decoration
COMPONENTS
Fastenings:
Trims:
Buttons- can be plastic, metal, leather, wooden or mother-ofpearl. All shapes and sizes, 2-hole, 4-hole or with a shank which
is like a short ‘stem’ on the back to allow for thicker layers to
fasten (like on a coat). More decorative.
Zips- can be lightweight plastic or heavier metal type. Can be
open ended or double ended, adds security to bags, can be
warmer or more wind-proof than buttons on a coat
Poppers- sometimes called press studs, can be metal or plastic. Often used
in childrenswear or baby wear as they are safe and easy
Buckles- decorative, adjustable, can be metal, leather or plastic
Clasps- used on bags or belts
Velcro- made from nylon, 2 sides that stick together, needs to be
sewn or stuck on securely. Can lose it’s sticking power but is easy
and quick
D-rings- D shaped metal rings used to attach straps onto bags or
some clothing
Hooks & Eyes- metal or plastic, fiddly to use, can come undone
but are good for waistbands of trousers and skirts as they lie flat
and are hidden
Ties- usually decorative feature, can be made of fabric, ribbon or
leather. Used at waist on blouses etc to give shape without
tightness
Braids- used for decoration and to define edges or features,
available in a variety of styles eg. Russia braid (narrow corded
braid) or Ric-Rac braid (wavy coloured braid used in childrens
clothing)
Ribbons- variety of widths and colours, metal threaded, checked
etc etc.
Piping- a round cord encased in a tube of fabric, used to add
definition and shape to edges or seams, used on; bags, sofas,
corset seams, necklines.
Petersham- a narrow band, like a ribbon but stiffer with ribs
running across the width. Used to stiffen waistbands or to keep
the shape inside hats
Bindings- a narrow band of fabric that fold over the edge of
products, used to give a neat finish to necklines or seam
allowances. Bias binding is cut across the grain of the fabric so it
will bend around a curved edge.
Fringing- applied to the edge of garments, can also be cut
leather to create fringing or tassels
Lace- decorative, often floral patterns, used as edging.
Beads- come in different shapes, sizes and materials. Often
hand-sewn onto designer items. Time-consuming but luxurious.
Sequins- come in different shapes and sizes, adds sparkle.
Diamantes- can be sewn on but now often glued on or heat set in
position, add sparkle
Motifs- pre-embroidered badges, sewn or glued onto garments
COMPONENTS
(cont.)
Threads
(important that correct
thread is used when
manufacturing clothing
not just for strength and
wear but to make sure
the thread will not break
or snarl up when used in
high speed machinery)
Sewing threads- most commonly used are cotton or polyester
Embroidery threads- softer, thicker and more lustrous than
sewing thread, variety of fibres used
Special effect threads- often with metallic content to add
sparkle, take care when ironing metallic or special effect threads
as they could heat up quickly or melt.
WORKING
PROPERTIES OF
FIBRES AND
FABRICS
Working properties can
be divided into;
Fibre Properties:
-
Aesthetic (to do with the look)
Functional
Comfort
Strength- whether or not a fibre will break under tension
Extensibility- how much a fibre can stretch until it breaks
Elasticity- how much a fibre will stretch and regain it’s original
shape
Fineness- the thickness of the fibre
Electrostatic charge- if a fibre contains ‘static’, it will be clingy
and not drape well. Synthetic fibres are prone to static.
Lustre- a slight shine
Thermal insulation- whether the fibre is a good or bad conductor
of heat
Flammability- all fibres burn, flammability is to do with whether
the fibre will catch fire quickly or not and how it reacts to heat, i.e.
will it melt?
Moisture absorption- the amount of liquid the fibre will absorb,
important to know because of comfort of wearer and ease of
washing/drying time etc.
Shrinkage- whether or not a fibre will shrink when washed,
tumble-dried or ironed etc.
WORKING
PROPERTIES
(cont.)
Fabric Qualities:
Testing of materials:
Durability-whether the fabric will withstand wear and tear, is it
resistant to abrasion, will rubbing cause the surface to pill (go
bobbly)
Creasing- will the fabric keep creases in or shed them easily
Stretch- how far the fabric will stretch
Formability- does the fabric hold it’s shape well?
Handle- is the fabric soft? How does it feel when handled?
Drape- how the fabric hangs, is the fabric supple and flexible?
Weight- is the fabric heavy or light, is the weight suitable for it’s
purpose?
Pattern repeat- is the printed pattern a large or small repeat?
This will effect how economical it will be to cut out the fabric
pieces so that the pattern lines up when made into a garment
Directional pile- the raised surface of a pile fabric or brushed
fabric, does it look different when looked at from different
directions, e.g. velvet that looked different from different angles.
Nap- the raised surface of a pile fabric or brushed fabric
Texture- what the fabric feels like, is it smooth, bobbly, rough etc
British Standards Institute (BSI)- develops the tests that set the
standards that products have to meet to ensure their safety and
quality. Products have to meet these standards and will be
awarded a number eg. BS 3320 (seam strength test)
Tests done in industry- tests are carried out on fibres, yarns and
fabric before they are manufactured. Testing is carried out under
strictly controlled laboratory conditions. Tests include; tensile
strength, seam strength, burst strength, tear strength, crease
resistance, flammability, drape etc etc.
Consumer testing of garments is also carried out to asses the
performance and acceptability of the product.
Consumer advice- information given to the buyer of the product
about the performance of particular fabrics, e.g. a symbol or logo
on the label to explain that the product meets certain BSI
standards. The kite mark shows that the product has been
independently tested under strict conditions and complies with
BSI standards. The CE mark shows that the product meets
European safety standards.
MANIPULATING
AND COMBINING
MATERIALS
Mixtures,
Blends and Laminates:
Combining materials:
Fabric mixture- is made using different fibres in the warp and
weft yarns, called a Union fabric. Different effects can be
achieved especially when dyed as fibres take dye differently
Fibre blend- different fibres are spun together to form a blended
yarn. This improves performance, quality, appearance or reduces
cost. Common blends are; polyester/cotton, wool/acrylic,
cotton/elastane, viscose/polyester.
Laminates- a laminated fabric has 2 or more textile layers that
are joined by adhesive or heat, e.g. when iron-on interfacing is
added to a whole piece of fabric
Interfacings- usually an iron-on non-woven web fabric used to
give body and shape, reinforce, prevent sagging or to stiffen
areas of garment
Underlinings- a lightweight second layer of fabric, often used on
white or light-coloured or see-through garments etc to add weight
and quality
Linings- a separate fabric used in the making-up of the product.
Linings add warmth, protection and cover construction details
Interlinings-an inner lining put between the outer material and
the ordinary lining of a garment
Impact of New
Developments:
Engineered fabrics- specially designed fabrics that have high
technical performance rather than for fashion use. E.g. chemically
resistant workwear, fire-protective wear, survival clothing,
geotextiles, medical textiles, high-tech sports clothing.
Microencapsulation- fragrances are trapped inside the fibres
adding a concept of ‘well-being’ to the product, e.g. lavender
encapsulated pillows or tights with floral or fruity aromas. The
effect is semi-permanent and will not transfer to other items
Anti-bacterial- fabrics which repel bacteria, usually contain silver
fibres (some plasters have these in) or anti-MRSA pyjamas which
prevent infection in hospitals
Wearable electronics- tiny devices incorporated into the fabric
which can control electronic components such as computer,
ipods, phones etc. Also tracking devices in clothing, particularly
useful for childrenswear, or hert-rate monitors in exercise wear.
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