Natural, Synthetic, Blended and Mixed Fibres. Blended and Knitted Fabrics
Textiles and fabrics are the same thing – all types of material. Fibres are the threads they are made up of. Fibres can be split into three main categories. Natural, manmade and regenerated.
Natural fibres are either grown or from animals:
Wool: Short hairy fibres can be spun (twisted) together to make a yarn ready to knit or weave with. It’s hard wearing and warm. Perfect for jumpers, jackets and carpets. Wool and hair from sheep, camels, alpaca and goats are widely used.
Silk: The cocoon from silk worms are harvested, cleaned and spun into a thread. A very fine fabric for making luxury cloths such as lingerie.
Cotton: Grow on a plant and looks like a cotton wool ball. It is harvested, cleaned and spun into a thread. Easy to knit and weave, suitable for jeans, T shirts and soft furnishings.
Flax: Made from the stem of the flax plant, it is shredded and woven. Suitable for soft, lightweight clothing.
Natural fibres are easy to grow, cheap and quick to harvest and provide a renewable and biodegradable material.
Other natural fibres include bamboo, alpaca, angora and mohair.
Regenerated fibres are natural materials that have been chemically treated to produce fibres.
Viscose: Wood pulp (cellulose) is mixed with sodium hydroxide and forced through a tine hole to produce a filament fibre. Often used in lingerie, linings and furniture.
Acetate: Cellulose mixed with acetic acid makes a cool, easy dying fibre. Good for sportswear and linings.
Synthetic fibres are derived from oil and processed in the same way a thermoplastic (making chains of molecules into polymers). Polymers are forced through tiny holes and hardened to make a filament (a continuous s thread – not like a natural staple fibre).
Acrylic: Cheap to produce, can be used to make fake fur, cloths and furnishings. It’s warm and resistant to dirt but can pill and get bobbly when rubbed.
Polyester: Strong and holds a pleat well. It can melt if heated too high. It is easy to wash and dry. Suitable for sportswear, sheets and curtains.
Elastane: A very stretchy fabric which is easy to care for. Washes and dries well, highly flammable. Used for leggings and tights, can be blended with other fabrics to make them stretch.
Microfibres: Microscopic fibres are knitted or woven into tight, strong materials which are warm and easy care. (Tactel, Tencell).
Fabrics can be blended by combining fibres before they are made into a fabric. Manufacturers can combine properties to fit their need. For instance polycotton is a mix of polyester and cotton, it makes a stronger, more hardwearing fabric which needs less ironing and doesn’t shrink. Elastane mixed with cotton makes a stretch, easy to dye fabric for figure hugging clothes.
Fabrics can easily hold pollen, mites and dust which can cause allergic reactions, tighter woven, thicker fabric can physically block particles. Some modern materials are treated with a thin layer of silver which is antimicrobial, anti odour and anti allergy, this is useful for sportswear, medical uses and bedding.
Different types of fabrics are made from different thicknesses of yarns. They can be textured to create a range of fabrics.
Fabrics are constructed into sheets of material in three different ways:
Weaving – threads are put on a loom (called the warp), other threads are passed under and over the warp threads (called the weft). Different combinations of warp and weft threads can create texture and pattern. A plain weave is basic under one, over one whereas a twill weave is over two, under one. This gives a stronger diagonal weave.
Plain weave: Under one over one, hardwearing, strong, smooth and cheap to produce. Used for lining, bedding and lightweight fabrics.
Twill weave: Over two under one produces a diagonal pattern, strong and able to drape its used in tweed, denim and tartan.
Satin weave: Over 4 (or more) under one so gives a very fine, shiny surface, It is prone to pilling and plucking. Used for delicate clothes and ribbon.
Jacquard Weave: A CAD program sets the loom to create a range of weaves to build up a pattern in rows. Often used for upholstery fabric and heavy curtaining.
Pile weaves: Woven fabrics have the loop cut off at the top to make velvet or cord.
Knitted fabrics are made through interlocking loops of yarn, the loops are excellent insulators as they trap in air. Knitting is also stretchy and excellent for knitwear, fleece and tights.
Layers of fibres are either glued together or forced together to create a fabric layer. They have no particular direction so can be cut without fraying. They don’t stretch and aren’t very strong. They are quick to produce so can be used to make disposable fabrics like surgical scrubs or dish clothes. Bonded fabrics can be bonded together by melting thermoplastic fibres or using adhesive.
Sewing on a sewing machine:
A sewing machine works by using two threads to repeatedly loop through fabric joining it together. A presser foot is lowered to hold fabric into place and press it onto feed dogs which pull it through the machine. There are different shaped feet to do different jobs. The zipper foot is half a foot to allow the machine to sew right up to the zip, its also used to sew piping on. Other shaped feet can sew on beads, buttons and bias binding.
In industry sewing machines are bigger and faster than domestic machines, they can sew through thicker material with more accuracy and greater speed. Over lockers are also used in industry, the can join and edge fabrics whilst also trimming the edges. CNC embroidery machines use an image input to sew pictures with thread as an output. CAD CAM machines can also be used for cutting fabrics ready for manufacturing several layers at a time.
Lay plans are the direction that fabric needs to be cut to give the best shape and drape as well as using the least material. Lay plans will ask for fabric to be cut on the fold to create one double sized piece or in the centre of a folded piece to provide a mirror image. You will need to be aware of pattern markings for your exam. Notches, arrows, darts, pleats, pocket positioning, seams, bias, balance marks and grain lines all have markings on the paper patterns that you will need to learn before your exam. These marks can be added to fabric by pinning on a paper pattern or drawing it on with tailor’s chalk or erasable fabric pens.
Notches are cut into fabric pieces to show where they join to another piece of fabric, they are cut by hand or band saw. Hot notching is used in industry to stop fabric fraying by melting a slight mark onto the edge of the fabric or dabbing a notch of UV light.
Paper patterns all also have a seam allowance which all pieces have added to make sure the are sewn together accurately. This is usually 10 - 15 mm with very little tolerance.
Fabrics are cut in a factory in a variety of ways. A band knife uses a band shaped blade which can cut through several layers at a time. Die cutting uses a sharp blade set into a block which is pressed down onto fabric. CNC machines such a laser cutters can also be used to cut through several layers.
Dyeing: There are several different ways of dyeing fabric. In industry vats of dye are used to give a constant and consistant colour to large amounts of fabric. Dip dyeing dips fabric into dye which absorbs colour up the grain creating an ombre effect. Tie dye dyes fabric after it has been tied into different shaped folds to create pattern when it is unfolded. Batik is when a wax resist is painted onto fabric before it is dyed.
Printing: Fabrics can be printed with pattern in a variety of ways. Silk screen printing forces ink through a screen with the pattern on, each layer of colour is a different screen. Roller printing has a roller of pattern for each colour, fabric is fed through the rollers which are fed with ink. Block printing uses inked blocks of wood with a pattern carved into it. Stencilling involves cutting the pattern out of a thin layer and painting or spraying ink over it.
Painting: Hand decorating fabric is possible by using fabric paint, crayon and felt tip. Silk can also be painted with ink. Dimensional paint is applied with a fine bottle nib and sits on the surface of the fabric creating a thick line.
Transfer printing: Images can be printed onto paper using an inkjet printer filled with sublimation ink. Once heated this ink can be transferred onto fabric. Image- maker is a liquid that can be painted onto printed images allowing it to be transferred onto fabric.
Embroidery: Hand embroidery is a techniques used to stitch images onto fabrics using coloured thread and breads. This can also be done with CNC machines following a CAD picture.
Applique: A technique which uses a collage of fabric and embroidery to create pattern and images on textile products.