Cotton, flax, ramie, hemp, jute, and other cellulosic fiber plants are all sources capable of producing textiles and fabrics that can be used to create knitted,woven, or nonwoven cloth material or fiber and yarn intended for fabric production.
All textiles are made through the use of fibers, thin strands of natural or artificial material. A fiber is a threadlike strand, usually flexible and capable of being spun into yarn.
About forty different fibers are of commercial importance. While textiles are primarily made from yarn, they are also made by felting,which is the process of pressing steamed fibers together to make cloth.
All knitted and woven textiles are made from yarn, while fibers alone are used to produce nonwoven cloth. The invention of the spinning machines and weaving machines during the Industrial Revolution greatly increased production and boosted the demand for fibers.
The textile industry has created a tremendous diversity of products available for use in clothes, home furnishings, and industrial and special applications.
These products are fabricated from natural resources such as animals, plants, and minerals, as well as from synthetic compounds. The major classifications of fibers by source are natural and artificial. Natural fibers are those fibers found in nature such as those from animals and plants.
About 5000 b.c.e., in Egypt’s Nile Valley, the flax plant was grown and processed into a cloth which was used to wrap mummies of Egyptian rulers.
By about 3000 b.c.e., people in Switzerland, India, and Peru were using cotton. The trade in textiles as an international commodity began around 1700 b.c.e. as cotton manufacture became more developed in China, Egypt, India, Iraq, and Africa.
In more recent history, the Industrial Revolution had a profound effect on the making of textiles, and textile manufacturing was established by the early 1900’s as an industry in many countries of the world.
|Flowering flax pants|
A major plant fiber source is the cellulose from plants. Cellulosic fiber can be found in a plant’s leaves, stems or stalks, seed pods, or fruit, as applicable. Pina, from the pineapple plant, is an example of a leaf fiber. Flax, jute, ramie, and hemp are fibers taken from a plant’s stem or stalk, also known as bast fibers.
Cotton and kapok are examples of seed pod and fruit fibers. Azlon fibers are produced from proteins found in soybeans and corn. Cotton and flax are the major plant fibers. One plant source which is not cellulosic is sap from the rubber tree, which can be processed into yarn.
The textile fabric that one can see and touch is composed of many individual fibers. The differences between fibers is determined by their chemical composition and individual unique structure. Molecular combinations of different elements are called compounds. Any particular (molecular) compound always contains the same type and number of elements and their atoms.
This gives each compound unique characteristics that determine its particular end use as a textile. When many molecules making up a compound are connected to one another in a line, they form a linear molecule. If this linear molecule is very long, it is called a polymer.
Animal hair, the living matter of plants, and some synthetic compounds all contain polymers. These long-string linear molecular compounds are the building blocks of fibers, which can then be made into fabrics. When polymers are formed synthetically, the process is called polymerization.
Only a few elements, in different combinations, make up all the natural and artificial fibers in textiles. For example, carbon, hydrogen, and oxygen, in various combinations, make up all the plant cellulosic fibers.
The protein fibers contain nitrogen as well. Chlorine, fluorine, silicon, and sulfur are other elements found in some fibers. Artificial fibers may be constructed from natural polymers that have been reshaped or from synthesized polymers made through chemical processes.
All fabric fibers have a characteristic length; these range from less than 0.375 inch to more than 40 yards (1 centimeter to 36 meters). A relatively short fiber ranging from fractions of an inch to a few inches is known as a staple fiber. A relatively long fiber measured in yards is known as a filament fiber.
A natural fiber is always used in the length in which it has grown. Artificial fibers, on the other hand, can be made in any length, regardless of whether they are reshaped or synthesized. The end use application of the artificial fiber will determine what its optimum length should be.
Artificial Fibers from Plant Sources After their early beginnings in the late 1800’s, there was wide-ranging development of artificial fibers in the 1900’s. There are two subgroups of artificial fibers: reconstituted or altered fibers made from natural sources, and fibers made from chemical compounds.
Artificial fibers are produced from compounds having a wide range of chemical composition and internal structure. However, this range of products can be broken down into groups of fibers that have similar composition and structure. A generic name is given to each of these groups.
For naturally occurring materials there are six generic families: acetate/triacetate, azlon, glass fiber, metallics, rayon, and rubber. All these families are legally defined and identified. Manufacturers making any of these products register a trademark name (or trade name) for their particular fiber.
Developed as a substitute for silk, the first artificial fiber was named rayon around 1925. Wood pulp is the major cellulose source of raw material used to produce rayon fiber. Cotton linters (a by product of cotton production) is another source. These sources are chemically processed to extract and purify the cellulose.
In regenerating cellulose into rayon, the purified cellulose undergoes several chemical and mechanical treatments before being forced through a spinneret machine. Acetate and triacetate are two other artificial fibers that are based on cellulose as a raw material.
Yarn is generally defined as a continuous strand of fibers spun together as a group which can then be used to make fabrics.
In practice, the majority of yarns are made in one of four ways: twisting a number of (short) fibers together, twisting a number of (long) filaments together, laying a number of (long) filaments together without twist, or twisting or not twisting a single (long) filament to produce amono filament (thread).
Yarn should be strong, flexible, and elastic so that it can be braided, knotted, interlaced, or looped as it is processed by various methods into a fabric.
A system of producing tightly twisted yarns results in worsted yarn that is firmer and smoother than regular yarn. Yarns are often made by blending two or more different fibers to combine the strong points of each.
When a manufactured yarn is texturized the long, plain, uniform yarn is changed to exhibit bulk, loft, and three-dimensional appearance. Stretchability may also be included. Yarns are curled, crimped, and twisted when texturized.
The major textile production methods are weaving and knitting. Minor methods produce braids, nets, lace, tufted carpets, and other products.
The only fabrics made which do not use yarn are those nonwoven fabrics made directly from fibers before they are processed into yarn. Felt is the traditional nonwoven product. Textiles can be classified by their weave or structure.
The value of a textile depends on many factors, primarily the quality of the raw material; the characteristics of the fiber/yarn; smoothness, hardness, and texture; fine, medium, or coarse fibers/yarn; density of yarn twist and density of weave; dyes/colors and pattern; and finishing processes.
A major method for producing fabrics is weaving, in which yarns are interlaced at right angles to each other. This method was used by the ancient Egyptians.
Weaving continued to be done by hand as a manual labor task until machines were developed during the Industrial Revolution. The invention of the flying shuttle and the steam-powered loomin the 1700’s were major contributors to automating the weaving process.
Three basic types of weaves are plain, twill, and satin. There can be variations within each of these three weaves. Besides the type of weave and the yarn types used, another variation of the weaving process is how close together the yarns are interlaced.
Knitted fabrics are formed by continuously interlooping one or more yarns. The knitting process may have been used to make fabrics as early as the first century. Knitting remained a hand labor skill until the eighteenth century, when powered knitting machines were developed.
Various knitting processes within the basic weft knit type include plain knit, purl knit, rib knit, and interlock stitch. Weft knits are produced by machine and by hand.
For another basic method, the warp knitting process uses a machine in which many parallel yarns are interconnected simultaneously to form loops in the lengthwise direction. Within the basic warp type process, tricot knitting and raschel knitting are two methods used.
Special processes that are variations of the two basic methods, sometimes in combination with special yarns, produce double knits, high pile knits, Jacquard knits, full-fashioned knits, textured knits, stretch knits, and bonded knits.
Finishes are the treatments given to fibers, yarns, or fabrics to improve their basic characteristics. The three types of finishes employed are mechanical treatments, heat treatments, and chemical treatments. It is common for one or more of these treatments to be applied to practically every fabric produced.
They change the appearance of the product, as in its look or feel, or add a functional characteristic such as waterproofing or flameproofing. Brushes, rollers, and hammers may be used in mechanical treatments.
Heat-setting of thermoplastic material is a common heat treatment. Chemicals such as acids, bases, bleaches, polymers, and reactive resins are used to chemically change the characteristics of a material.
The aesthetic finishes, by process name, include bleaching, brushing and shearing, calendering, carbonizing, crabbing, decating, fulling, glazing, mercerizing, napping and shearing, scouring, singeing or gassing, sizing, and tentering.
The functional type finishes make textiles abrasion-resistant, anti bacterial, anti soil and anti stain, antistatic, durable press (permanent press), flame/fire retardant/resistant, moth repellent, permanently crisp, shrink resistant, waterproof, water repellent, or wrinkle resistant.
The major elements of fabric design are the visual (how it looks) and the tactile (how it feels). Solid colors or shades of black, white, and all colors can be applied in an unending combination of patterns and designs.
The feel of the fabric can be varied by the types of yarn used, the fabrication method, how the color pattern is applied, and the types of finishes used. Dyeing and printing are two major methods of applying a pattern, color, or both, to a fabric. Dyes can be applied to fiber, yarn, or fabric.
Color can be applied by at least three methods: directly, the discharge method, and the resist or reserve method. Printing is typically done by methods such as roller printing, block printing, toiles de Jouy, stencil, screen printing, spray printing, electroplating, and by hand.
The Textile Industry
The textile industry is dynamic, with new processes, techniques, and methods constantly being developed. Sometimes they add to, and sometimes they replace, previous ways of operating.
The idea of evolution and change can be applied to all parts of the industry, such as raw material and fiber development, yarn production technique, fabrication method, finishing technology, and the printing, dyeing, and design processes. The primary goal of all research and development is to sell a product attractive to consumers.
Consumer research is an important factor in determining what the public wants, thereby helping to drive and focus the technology in particular directions. Federal laws govern textile labeling and product advertising, and the industry has developed voluntary self-regulating product quality and testing standards.