Textile Dyeing Procedures Essay Research Paper Textile — страница 2

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excess dye is washed off. A continuous dyeing process is used in dyeing of carpets. A machine called a Festoon steamer can be used. The carpet is placed on guide rolls so that the surface of the carpet always faces outward. This prevents the compressing of the carpet when it s rolled in the steamer. Dyes are applied in streams and metered onto the surface. Special effects can be produced by the way the dye is applied: (the stream can be momentarily interrupted to produce a patterned effect). A semi continuous process is one in which the production rate is momentarily interrupted for the material to soak in the dye. Pad-batch dyeing is on such method, it is mainly used for dyeing cotton fabrics with reactive dyes. The fabric is padded wit the dyes and chemicals, wound on a roll,

and then allowed to set from 4 to 24 hours to allow the dye to react with the fibers. The reaction can be sped up by using heat, higher alkalinity, and selecting more reactive dyes. Scouring and bleaching of fa ic can be done by a similar cold pad-batch process. There are three methods of pattern dyeing and printing: direct, resist, and discharge printing. In direct printing a design is transferred to fabric by a copper roll. In resist printing a dye repelling substance is applied to cloth that will be place nto a dyebath. This is a popular method for creating white designs on a colored background. Discharge printing takes place by first dyeing the whole fabric, then printing a pattern on the fabric with a oxidizing or reducing agent to create a white pat rn like in discharge

printing. Three popular printing procedures are roller screen and transfer printing. Roller printing is a direct method that takes place by an engraved copper roll that has been dipped into dye and had the excess scraped off. A different engraved roll is used for each color in the design. The fabric passes through the rolls and comes ut printed. The print is then set into the fabric permanently by heat. Prints can consist of up to 16 different colors and can be produced at rates of up to 100 to 150 yards per minute. Another method called screen printing, a type of resist printing, uses screens made by covering a frame with fabric made of silk, nylon, metal, or polyester filaments. Instead of the traditional method of stenciling , today a resist design is applied the fabric by use

of a photo sensitive emulsion that hardens when it is exposed to light. Like in roller printing a different screen is used for each color. Transfer printing is one of increasing popularity because it requires no water, is relatively fast, and can be carried out by less skilled workers. By transferring, complex multi designed prints can be easily transported to fabrics. The paper has bee printed with disperse dyes with sublimation temperatures around 200 degrees Celsius. The transfer takes place from the paper to the fabric due to the hydrophobic fabric having a high affinity for the dye in the vapor phase. The printing takes place at nly about 8 1/2 yards/minute. Bibliography Cant, Jennifer and Fritz, Anne. Consumer Textiles. Melbourne: Oxford University Press, 1988 Clapp, Anne

C., Hudson, Peyton, B., and Kness, Darlene. Joseph’s Introductory Textile Science. Holt, Rinehart and Winston, Inc. 1993 Labarthe, Jules. Elements of Textiles. New York: Macmillan Publishing Co., Inc, 1964 Lyle, Dorthy, S. Modern Textiles. Toronto, Canada: John Wiley & Sons, Inc, 1976 Perkins, Warren, S. Textile Coloration and Finishing. Durham, North Carolina: Carolina Academic Press, 1996