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Textile Institute of Pakistan, Karachi. TEXT202 (Fabric Technology) What is the yarn? The yarn is a continuous strand composed of either natural or manmade fibres or filaments and is used in weaving and knitting to produce cloth....

Textile Institute of Pakistan, Karachi. TEXT202 (Fabric Technology) What is the yarn? The yarn is a continuous strand composed of either natural or manmade fibres or filaments and is used in weaving and knitting to produce cloth. OR A yarn is defined as a product of substantial length and relatively small cross-section consisting of fibres and/or filament (s) with or without twist. Textile Product Chain Yarn Classification Prepared By: Shakeel Ahmad Paracha Page 1 of 3  Textile Institute of Pakistan, Karachi. TEXT202 (Fabric Technology) Yarn Classification Yarn Classification Yarn Classification Prepared By: Shakeel Ahmad Paracha Page 2 of 3  Textile Institute of Pakistan, Karachi. TEXT202 (Fabric Technology) Yarn Classification Prepared By: Shakeel Ahmad Paracha Page 3 of 3  Textile Institute of Pakistan, Karachi. TEXT202 (Fabric Technology) What is Fabric? A fabric is defined as the product of textile made by the combination of yarns and/or fibres and filaments having enough strength, flexibility and cover and can take the shape of a garment. Generally, produced by the combination of yarns (woven & knitted fabrics); however, fabrics can also be made by only fibres (non-wovens). Classification/types of Fabrics Woven Fabrics o Fabrics that are made by the interlacement of two sets of yarn. Knitted Fabrics o Fabrics that are produced by transforming the yarn (s) into a loop then intermeshing the loop with it adjacent loops on both sides and above & below. Non-Woven Fabrics o Non-woven fabrics are broadly defined as sheet or web structures bonded together by entangling the fibres or filaments mechanically, thermally, or chemically. Bonded Fabrics o A non-woven fabric in which webs of fibres are held together by a bonding material. This may be an adhesive or a bonding fibre with a low melting point. Felted Fabrics o Felted fabrics are produced by matting, condensing and pressing fibres together. Tufted Fabrics o Tufted fabrics are made by the combination of: Foundation Cloth Tufts Braided Fabrics o A braided fabric is a rope like, which is made by interweaving three or more yarns in a diagonally overlapping pattern. Laced Fabrics o A laced fabric is an open work fabric made from intermeshing threads into a fabric. Prepared By: Shakeel Ahmad Paracha Page 1 of 5  Textile Institute of Pakistan, Karachi. TEXT202 (Fabric Technology) Comparison between Different Fabrics Woven Fabrics o Woven fabrics are produced by the interlacment of two sets of yarns. o Sizing is required before weaving. o Yarn preparation is must. o The production capacity of the woven fabrics is less than that of knitted fabrics. o The production cost of the woven fabrics is higher. o About 48 % of the fabrics are produced by weaving techniques in the textile section. o The elastic property of the woven fabrics is less than knitted fabrics. o Dimensional stability is higher than knitted fabrics. Knitted Fabrics o Fabrics that are produced by transforming the yarn (s) into a loop then intermeshing the loop with its adjacent loops on both sides and above & below. o One set of yarn is used. o Do not require sizing. o Yarn preparation is not so necessary. o The production capacity of the knitted fabrics is more. o The production cost of the knitted fabrics is less. o About 52 % of the fabrics are produced by knitting technology in the textile section. o The elastic property of the knit fabrics is higher than woven fabrics. o Dimensional stability is lower than the woven fabrics. Non-woven Fabrics o Non-woven fabrics are not the true fabrics as they have no internal structure. o Felting and bonding techniques are used to produce the non-woven fabrics. o Woven fabrics are much stronger than non-woven fabrics. o Non-woven fabrics are mostly used for interlining or to make hats or other handicrafts. o Non-woven Fabrics do not require shedding, filling insertion and beat up. Miscellaneous Fabrics o Miscellaneous fabrics can be formed by the diagonal interlacing of yarns. o Yarn system of loops is 'sewn' or ‘stitched' through a primary backing fabric, usually a woven fabric. o Usually back-coated in a later process to secure tufted loops. o Miscellaneous Fabrics do not require shedding, filling insertion and beat up. Characteristics of Woven Fabrics Stretching is restricted both lengthwise & widthwise. Excellent covering power. Processing and handling both are easy. They have a long life. Dyeing & printing is easily carried out. Prepared By: Shakeel Ahmad Paracha Page 2 of 5  Textile Institute of Pakistan, Karachi. TEXT202 (Fabric Technology) Weaving Machines The actual process of weaving, i.e. the interlacement of warp and weft is carried out on a machine called as a loom. There are several types of looms. Generally, looms are classified based on the method of weft insertion they use. Types of Weaving Machines Uses of Woven Fabrics Apparel Bed linen & tablecloths Tapestry & upholstery fabrics Curtains Towels Floor coverings as carpets, rugs & mats Filter cloths Tent fabrics Umbrella & parachute fabrics Fireproof & waterproof fabrics Space age garments like astronaut’s suits, etc. Prepared By: Shakeel Ahmad Paracha Page 3 of 5  Textile Institute of Pakistan, Karachi. TEXT202 (Fabric Technology) Types of Woven Fabrics Dress fabrics Denim Terry toweling Velvets & velveteens Corduroys Leno fabrics Jacquard fabrics Brocades Damasks Woven carpets (Wilton & Brussels) Specifications of Woven Fabrics Ends per inch Picks per inch Warp count Weft count Warp & weft crimp % The weight of fabric per unit area Weave design Prepared By: Shakeel Ahmad Paracha Page 4 of 5  Textile Institute of Pakistan, Karachi. TEXT202 (Fabric Technology) Prepared By: Shakeel Ahmad Paracha Page 5 of 5  Textile Institute of Pakistan, Karachi. TEXT202 (Fabric Technology) Flow Process of Weaving Weaving Preparation Process Weaving preparation process consists of: o Warp Preparation Process o Weft Preparation Process Both the warp and weft yarns must undergo a series of preparation before they could be taken on the loom and woven into a fabric. The preparation of warp is much more extensive as compared to weft preparation. The weft preparatory processes depend upon the type of the loom, i.e. whether the loom is a shuttle or shuttle-less. Prepared By: Shakeel Ahmad Paracha Page 1 of 1