Cotton today is the most used textile fiber in the world. Its current market share is 56 percent for all fibers used for apparel and home furnishings and sold in the U.S. Another contribution is attributed to nonwoven textiles and personal care items. It is generally recognized that most consumers prefer cotton personal care items to those containing synthetic fibers. World textile fiber consumption in 1998 was approximately 45 million tons. Of this total, cotton represented approximately 20 million tons. The earliest evidence of using cotton is from India and the date assigned to this fabric is 3000 B.C. There were also excavations of cotton fabrics of comparable age in Southern America. Cotton cultivation first spread from India to Egypt, China and the South Pacific. Even though cotton fiber had been known already in Southern America, the large-scale cotton cultivation in Northern America began in the 16th century with the arrival of colonists to southern parts of today’s United States. The largest rise in cotton production is connected with the invention of the saw-tooth cotton gin by Eli Whitney in 1793. With this new technology, it was possible to produce more cotton fiber, which resulted in big changes in the spinning and weaving industry, especially in England.CHARATERISTICS OF COTTON
Cotton, as a natural cellulosic fiber, has a lot of characteristics, such as;
*Comfortable Soft hand
*Easy to handle and sew
The color of cotton samples is determined from two parameters: degree of reflectance (Rd) and yellowness (+b). Degree of reflectance shows the brightness of the sample and yellowness depicts the degree of cotton pigmentation. A defined area located in a Nickerson-Hunter cotton colorimeter diagram represents each color code. The color of the fibers is affected by climatic conditions, impact of insects and fungi, type of soil, storage conditions etc. There is five recognized groups of color: white, gray, spotted, tinged, and yellow stained. As the color of cotton deteriorates, the process ability of the fibers decreases.
Work at the University of Tennessee has led to color measurement using both a spectrometer CIE-based average color measurement and a color uniformity measurement using image analysis to improve the accuracy and provide additional measurement for color grading . Later the investigators developed two color grading systems using expert system and neural networks.
About 30% of world cotton machines harvest production. Australia, Israel and USA are the only countries where all cottons are picked by machines. Fifteen percent of world cotton production is ginned on roller gins and almost all rest of cotton is saw ginned in most countries .Cotton fibers in non-wovens are generally used in their bleached form. A lot of research and development has taken place for the efficient production of bleached fibers. The Kier bleaching process produces most of the bleached cotton fibers. Since cotton of lesser grades is useful for non-wovens, a conventional cleaning system does not suffice. This might include a coarse wire carding, called Cotton Master Cleaners, for cleaning the cotton.