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Today garments are not only for fulfilling the basic need of clothing but also to satisfy our aesthetic senses. Nothing is beyond the human power. He thinks, imagines and creates. Such is the level of his imagination that almost everything has been converted into textile right from the parts of plants to animals and minerals too. As if the natural materials were not enough, he has developed techniques for creating synthetic fibers even from chemicals.Garment manufacturing is not only an activity now, it has become a journey of art. This journey of fiber to garment starts from selection of fibers which are then converted into yarns through spinning and other methods. After that begins the journey from yarn to fabric which involves processes like weaving, knitting, tufting, felting etc.Then comes the finishing processes which prepares the fabric for its beautification through
dyeing and printing. All these processes have to be carried out with such precision that textile manufacturing has become a full fledged academic subject with the purpose to produce textile experts. This study is just an attempt to introduce the basic processes involved in fabric construction to the people related to textile industry.
Fibers to Yarns
Textile Industry is related to many more industries- agriculture, animal husbandry, mining of metals and minerals, forestry, chemical research and many others. The fiber is produced in fields in the form of cotton, flax and other fibrous plants. It is obtained from animals and insects like, sheep, goats, silkworms etc.
Minerals like asbestos and wollastinite are also mined for getting fibers. As if these natural sources of fibers are not enough, they are chemically researched upon and synthetic fibers are prepared. As such yarns are formed from both, natural fibers such as cotton, hemp, linen, jute, wool, silk as well as from manmade fibers such as nylon and rayon.
URL: Discover the other categorizations of fiber
Yarn Formation
When the short fibers are twisted together, they take the form of yarn. Thus, yarn is a continuous filament of interconnected fibers used for making textile. Yarn can be made by one of the several techniques of spinning.
Spinning
The process of twisting together of fibers to form yarn is called spinning.
The basic processes included in spinning can be listed as carding, combing, drafting, twisting and winding. When the fibers pass through these processes, they are subsequently formed into lap, sliver, roving and finally yarn.
Two of the major methods of spinning are Ring Spinning and Open- End Spinning. Other methods include friction spinning, vortex spinning, air- jet spinning, etc.
Formation of Filament Yarns
The man made filaments are produced by different methods and they can be formed directly into yarn without the use of techniques to connect fibers together to form the required lengths. These yarns are called Filament Yarns.
There are many methods for making such types of yarns- wet spinning, dry spinning, melt spinning, bicomponent spinning etc.
Formation of Integrated Multicomponent Yarns
Yarns are also produced by combining staple and filament fibers in order to obtain certain of the characteristics of each. These combinations are known as Integrated Multicomponent Yarns. Integrated composite spinning and coverspun are two important methods for preparing such yarns.
URL: Interesting notes about how yarns are made without connecting fibers!
Yarns to Fabrics
Fabric is formed by networking of natural or synthetic yarn. Weaving and knitting are two of the major methods of fabric construction. Other methods like tufting, stitch-bonding, felting are also used for constructing fabrics. Non woven fabrics have also gained importance these days.
Weaving
In the process of weaving, two distinct sets of yarns called the warp and the weft are interlaced with each other to form a fabric. Yarns made from both, natural fibers and synthetic fibers, are used for weaving textile. Other fibers can also be used for weaving.
Four major operations are involved in any type of weaving- Shedding, Picking, Beating up (Battening), Taking up and letting off.
Knitting
After weaving, the most frequently used method of fabric construction is knitting. Knitting industry has two main divisions- One manufactures knitted goods for apparel production, sewing centers, consumers and others. The other division manufactures finished apparel such as hosiery, sweaters and underwear.
Construction of Knitted Fabric
The construction of knitted fabric is evaluated by the number of stitches or loops. When the interlocking loops run lengthwise, each row is called a wale.
A wale can be compared with the warp in woven fabric. When the loops run across the fabric, each row is called a course. A course corresponds to the filling, or weft.
Weft and warp knitting
There are two major varieties of knitting: weft knitting and warp knitting. In weft knitting, one continuous yarn forms courses across the fabric. In warp knitting, a series of yarns form wales in the lengthwise direction of the fabric.
Tufting
Tufting is a type of textile weaving which is done by pushing extra yarns onto a fabric. Many needles simultaneously punch the fabric at predetermined distance for extruding the fibers.
Tufting is mainly done to manufacture rugs, carpets, blankets and upholstery. Sometimes, the backs of rugs and carpets are coated with a binder to prevent abrasion.
Stitch Bonding
Stitch Bonding or sewing- knitting technique is used to manufacture different kinds of constructions such as flat fabrics, piles, nonwovens etc. It has many variations such as Malimo technique and Malivlies technique. There is no need to produce yarn for this method.
Felting
The felted fabrics are produced directly from fibers matted together. Wool is the usual raw material for making felted fabrics although
other fibers like fur are also used sometimes for the purpose. Felts are used for making hats, slippers, shoes, insoles, earmuffs, table paddings etc. Since these fabrics have insulating and noise absorptive properties, they are extensively used for industrial purposes.
Nonwoven Fabrics
The nonwoven fabrics are made by bonding or interlocking of fibers through mechanical, chemical, thermal or solvent means. The methods of manufacturing differ on the basis of fibers used, techniques of laying these fibers and the bonding agents used in the process. Many types of fibers are used for nonwovens such as cotton, wool, rayon, acetate, nylon, polyester, acrylic, modacrylic, polypropylene, and polyethylene.
The fibers are processed through various operations like opening, conditioning and blending. Then webs of fiber are made and arranged into layers. Various methods are used for affixing these fibers which include heat, resin, latex or other bonding agents.
Many techniques are adopted for web formation. Parallel-laid web, Cross-laid web, random-laid web, air-laid web, wet-lay web are some of the methods used for web formation. Several methods of bonding are there for forming nonwoven fabric which include Resin Bonding, Latex Bonding, Gelatin Bonding, Spunbonding, Melding, Radiation Bonding etc.
Finishing Processes
After construction of fabric through one of the many techniques described above, it is known as greige good or gray good. This simply denotes any unfinished fabric. Many finishing processes are employed for improving the appearance, feel and durability of the fabric. These processes are broadly classified as Preparatory Processes, Stabilizing Processes, and Textural Processes.
Preparatory Processes
The unfinished fabric or the gray good may contain many impurities such as dirt, soil, sizing, oils and other additives. As such, they need to be cleaned before proceeding towards finishing of the textile. As a result, processes such as Singeing or Gassing and Bleaching are done which removes all the impurities and decolorize the fabric for further finishes.
Stabilizing Processes
Stabilizing processes are required for improving properties such as strength, luster, and other qualities of the fiber. Mercerization is done for improving properties such as fiber strength, shrinkage resistance, luster, and dye affinity. Ammoniating is done for increasing luster, affinity for dyes, abrasion resistance, smoothness etc. particularly of cotton and rayon fabrics. Shrinking is done to avoid the subsequent shrinkage of the fabric while usage. Tentering makes the fabric even for further processing. Decating improves luster, appearance, feel as well as preshrinks the fabric.
Textural Processes
Textural processes are meant for improving the texture of the fabric such as stiffness, smoothness, weight or
strength. Temporary stiffening, permanent stiffening, weighting, calendering, glazing, embossing, moireing, cire process, beetling, raising, napping, sanding, gigging, tigering, shearing etc. are some processes which help in improving the texture of the fabrics.
Finishing Processes for Functionality of Fibers
Some finishing processes improve the appearance and feel of the treated fabric. There are other finishing processes that give special properties to the fabric for particular functions. Various chemicals and solutions are used to make the fabrics water repellent, flame retardant or slip resistant.
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Dyeing
Dyeing is a method which imparts beauty to the textile by applying various colors and their shades on to a fabric. Dyeing can be done at any stage of the manufacturing of textile- fiber, yarn, fabric or a finished textile product including garments and apparels. The property of color fastness depends upon two factors- selection of proper dye according to the textile material to be dyed and selection of the method for dyeing the fiber, yarn or fabric.
Dyes
Dyes are used for coloring the fabrics. Dyes are molecules which absorb and reflect light at specific wavelengths to give human eyes the sense of color.
There are two major types of dyes - natural and synthetic dyes. The natural dyes are extracted from natural substances such as plants, animals, or minerals. Synthetic dyes are made in a laboratory.Chemicals are synthesized for making synthetic dyes. Some of the synthetic dyes contain metals too. Basic (cationic) dyes, acid (anionic) dyes, mordant dyes, vat dyes, pigment dyes are some of the commonly used dyes.
Dyeing Methods
Color is applied to fabric by different methods and at different stages of the textile manufacturing process.
Stock dyeing
The fiber is dyed even before it is spun.
Top dyeing
Top is the combed wool. In this method, the fiber is dyed in the stage just before the appearance of finished yarn.
Yarn dyeing
It is done after the fiber has been spun into yarn.
Piece dyeing
In this method, small batches of constructed natural colored fabric are dyed according to the demands for a given color.
Solution pigmenting or dope dyeing
Dye is added to the solution before it is extruded through the spinnerets for making synthetic filaments.
Garment dyeing
Dye is applied to finished products such as apparels and garments.
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Printing
When colored patterns and designs are applied to a finished fabric for its decoration, it is called 'Printing'. In printing, the color is firmly affixed to the fiber so that it may not be affected by washing and friction. Textile printing is related to dyeing in the sense that in both the processes color is applied to the fabric. The difference lies in the fact that in dyeing, the color is applied uniformly to the whole fabric whereas in printing one or more colors are applied to it in selected parts only, and in sharply defined patterns.
The Dyes used for printing mostly include vat, reactive, naphthol and disperse colors which have good fastness properties. Pigments are also used extensively for printing.
Methods of Printing
For printing color on a fabric, mostly three techniques are applied: Direct Printing, Discharge Printing and Resist Printing. In Direct Printing, the desired pattern is produced by pressing dye on the fabric in a paste form. In Discharge Printing, the fabric is dyed in piece and then it is printed with a bleaching agent that destroys the color in the designated areas. In Resist Printing, a resist paste is fixed onto the fabric and then it is dyed. The dye affects only those parts that are not covered by the resist paste.
There are various methods of printing in which one of the above three techniques is used. Block Printing, Roller Printing, Duplex Printing, Stencil Printing, Screen Printing, Transfer Printing, Jet Spray Printing, Electrostatic Printing, Photo Printing, Batik Dyeing, Tie Dyeing, Airbrush (Spray) Painting and Digital printing are some of such methods.
Apparel Making
The actual ready to wear apparel involves many more processes right from pattern drafting to garment construction which include pattern designing and pattern making, grading, marker making, apparel cutting, sewing, pressing and finishing.
Pattern making
sized patterns are created according to certain rules.
Pattern grading
In this method, small batches of constructed natural colored fabric are dyed according to the demands for a given color.
Apparel Cutting
Fabric is cut using traditional as well as computerized cutting systems.
Apparel Sewing
sewing is done on a large scale through various machines.
Pressing and Finishing
garments are examined, pressed, tagged and bagged in the pressing and finishing department.