Creado por darkangelforgiven
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Fabric is made by interlocking two yarns at right angels to each other. The yarn that go horizontally across the fabric are the weft yarns. The yarn that lie vertically in the fabric are called warp yarns, and these run the length of the fabric, which is known as the straight of grain. The diagonal of the woven fabric is known as the bias. The edge of the fabric is finished by the weft yarns wrapping around the warp yarns. This edge is called the selvedge. Weaving is a method of making fabric on a piece of equipment called a weaving loom.A shuttle loom is used to create simple, plain weaves, a Jaquard loom is used to create complex weaves.Woven fabrics are made using the following processes:The yarn is wound on to large bobbins that fit the shuttles used to carry the weft thread from side to side.The warp threads are placed on a huge beam. The addition of a sizing (starch solution) makes the yarns smoother and stronger.The yarn is then drawn through the needle. These are fine rods with eyes in them for lifting different threads. This is calleddrawing.Properties of woven fabrics. The side edges, known as the selvedges, do not fray unless cut. They can be either densely woven or loosely woven (for example, viola, muslin). The fabric is strongest along the grain of fabric. The warp yarns are also stronger than the weft. 1. Plain Weave.The most basic of the three fundamental types of textile weaves.Each warp fibre simply passes alternately under and over each weft fibre.The fabric is symmetrical, strong, and hardwearing. For this reason, it is used for fashion and furnishing fabrics.2. Twill weave.One or more warp fibres alternately weave over and under two or more weft fibres in a regular repeated manner.This gives a diagonal patter on the fabric surface.The fabric also has a smoother surface than the plain weave.It is strong, drapes well, and is used for jeans, jackets, and curtains.
3. Satin weave.A complex arrangement of warp and weft threads, allowing longer float threads either along the warp or weft, and fibres to be woven in the closest proximity.The reflected light creates a smooth and shiny surface called satin, the reverse side, however, is invariably dull and non-shiny.It is used in things like wedding dresses, and is very expensive.
Made up of a range of interlocking loops. The loops run through the fabric and hold the fabric together; if the loops are broken, then the fabric will come apart.There are two types of knitted fabrics: weft knitted and warp knitted.1. Weft knit.This can be done by hand (using knitting needles) or by using a machine. The loops run horizontally across the fabric and interlock with the rows above and below. If this is done by hand, the pieces of the garment are knitted individually and then joined together. Hand knitting produces individual items such as jumpers, hats, and gloves. Weft knitted fabrics can be created on a flat bed machine or a circular knitting machine.Circular machines are popular in factories, as they take up less room than flat bed machines and they are faster. Fabrics can be made in straight lengths or in tubes, which are useful for items such as socks. It can also be made using short filament yarns, and natural or synthetic fibres. Plain knitted weft fabric, known as single jersey, is made on a machine. It tends to curl at the edges, which makes it hard to work with. Double jersey is made using two sets of yarn, and is thicker so it is more stable, although it is also less strechy. Characteristics of weft knitted fabrics: High elasticity and strength. Retains warmth as the loops trap air between them. It is easy to tell which are the back and the front of the fabric, as the top of the loops make horizontal ribs on the back. Unravels or ladders easily if the fabric is cut or pulled - this means the seams have to be very secure. Looses its shape very easily. Types of weft knitted fabrics and their uses: Single jersey - T-shirts, sweaters. Rib fabric - socks. Interlock - sportswear. Fake fur - fur coats, trimmings, shoes. Pique - sports shirts. 2. Warp knit.Warp knitting is always done using a machine. The loops run the length of the fabric and are linked side by side, and the yarns are fed in the direction of the fabric. This type of knitting is like a series of vertical chains and is mostly made using filament yarns.Characteristics of warp knitted fabrics: Hard to unravel, so less likely to ladder, which makes it easier to cut and sew. Faster to produce than weft knitting. Like all knitted fabrics, it has elasticity, but is able to keep its shape. It is a very expensive fabric to produce, as it takes a long time to set up the machine, which has to be done by hand. Types of warp fabrics and their used: Locknit (terry) - furnishing fabrics, bed sheets. Warp knit velour - leisure and sportswear, such as swimming costumes. Lace and net - bridal wear, fabrics, and trimmings. Fleece - fleece is a warp knitted fabric with extra yarns layered into it and then brushed to produce a napped surface that is soft and raised. Fleece is usually made from polyester fibres and can be double faced, with a nap on both sides, or a single faced with a nap on one side. KNITTING AND NEW TECHNOLOGY.In recent years, CAD (Computer Aided Design) has enabled the designer to design using simulated stitches. With the use of computer-controlled machines, the knitter or technition is also able to make changes and adaptations to the knitted product as needed via a computer keyboard.Further advances in knitting technology, using seamless integrated knitting, means that garments can be knitted without seams.
Non-woven fabrics fall into two groups: Felted fabrics and Bonded fabrics.In non-woven fabrics, fibres are turned into fabric without first being made into yarn, as is the case with woven and knitted fabrics. Instead they are made by arranging fibres into layers, which face either in one direction or randomly.Layers are then built up to form a web. These have little natural strength so in order to hold the layers and fibres together to make a fabric, they are either felted or bonded.Felted Fabrics.1. Wool feltsThese are made from wool fibres, which are short curly staples, which have small scales along their length.When they are treated with heat, moisture and sometimes alkaline chemical, the fibres curl up. The scales prevent the fibres from straightening out again, and this causes the wool to shrink in size and felt together.The same thing happens when you wash a wool jumper at a high temperature.These felts can be moulded into shapes such as hats by using steam.Felts are good insulators, as air is trapped in the web of fibres; they do not fray, and they can be made from recycled wool.They my be used for insulation, collar back (they can be stitched to hold the shape of a tailored collar) hats, toys and billiard cloths.However, the disadvantage of this fabric is that it is not very strong.Many interior designers use strong industrial felts to design unusual furniture such as floor cushions.2. Needle felts. These can be made from almost any fabric. The web of layers is punched through with hot barbed needles that pull the fibres through the fabric to hold it together. Like the wool felts, these fabrics do not fray and they tend to be lighter than wool felts. They are used for interlinings, upholstery, mattress covers and filters. Bonded webs.Bonded webs can be made in three ways and are then strengthened to improve their quality.1. Dry laid.A web of fabrics is laid onto a drum and hot air is pulled through the drum. This softens the fibres, which join together as they are compressed by the air.2. Wet laid. These webs are created just like paper. The fibres are mixed with a solvent that softens the fibres. This releases a sticky substance, which glues the fibres together where they touch. They are laid flat to dry. The glueing process strengthens the bond. 3. Direct spun. The fibres are spun directly onto a conveyor. This can be done in a random way or an oriented way (crisscrossing over each other). Adhesive (glue) is added to the fibre web by either spraying or dipping, and the web is then pressed to make it stick together. If the fibres in the web are thermoplastic, they can be bonded together by heating and being pressed together. This could be done all over the fabric, or just in places. Bonded fabrics are relatively cheap to produce, they do not fray, and as they are permeable (water can pass through them) they can be used as filters. They have no grain and can be cut in any direction, and they have no stretch or give. They do not have much strength, and are often strengthened with stitching or glueing. USES OF BONDED WEB: Bonded fabrics are used for disposable items such as table linen, underwear, cleaning cloths, and hospital items such as masks and hair coverings. Bonded webs are also useful as interfacings because of their stability and lightness. Some are sewn into place and some are printed with glue so that they can be ironed onto the back of the fabric to be stiffened. Some are produced as a long strip, especially for use on hems. Vilene is a type of bonded fabric used in interfacing. Bonded webs can be used for: Stabilizers for embroidery work. Soluble stablizers where you can embroider then wash or iron the stablizer away, leaving a lacy fabric. Interfacing put into garments, such as collars on shirts, to help keep the shape of the garment.
Woven
Knitted
Non-woven fabrics: Felted and Bonded
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