Tufting

Whether or not it is obtained depends on the washing mechanism allowing the shrinkage, and hence the crimp, to develop prior to the completion of regeneration. Crimp development only occurs fiiUy in staple fiber processes where the sluicing operation allows the cut tufts of acid tow to expand freely in ample volumes of hot Hquor. 

C. E. Messer, M Survey Keport on Eithium Hydride, Tufts University, Medford, Mass., 1960. 

Fibers. Polypropylene fibers are extensively used in carpeting. Bulked continuous filament yams are commonly used in carpet facing in the level loop carpets used in commercial buildings however, nylon remains the dominant face yam in tufted household carpets. The advantages of polypropylene carpeting are superior stain resistance and low moisture absorbance. Polypropylene sHt tape fibers are heavily used in carpet backing. 

Most of the textured apparel and industrial yams are woven or knitted directly into fabric. The carpet BCF yams can be tufted directly off package into loop pile or velvet constmctions. For the textured saxony constmctions, the BCF and the spun staple yams must be ply-twisted and heat-set. The heat-setting temperature for nylon-6 and nylon-6,6 is 180—220°C in hot—dry atmosphere, and 120—140°C in saturated steam. The yams are twist-set in pressurized autoclaves or continuously on the Superba and Suesson machines (121). Before setting the twist, the yam is heated and relaxed for predevelopment of the bulk. 

Light-Duty Recreational Surfaces. Artificial surfaces intended for incidental recreational use, eg, swimming pool decks, patios, and landscaping, are designed primarily to provide a practical, durable, and attractive surface. Minimum cost is a prime consideration and has driven the quaUty of some such products to a low level. Most surfaces in this category utilize polypropylene ribbon and a tufted fabric constmction (see Olefin polymers, polypropylene). ... 

Fig. 3. Constmction of (a) pile fiber held in place by latex (tufted) and (b) pile fiber tied into backing (knitted) grass-like artificial surfaces.

A machine with approximately 1000 needles continuously produces a fabric 5-m wide. The assembly process is more complex, slower, and more expensive than tufting. The pile yam and stitch yam are inserted into the knitting needle, and the stuffer yam is interlocked with the others through a separate feed mechanism of the machine. As with tufting, the loops of the pile fabric formed are sHt, creating the desired individual blades. 

Edel Grass knitted nylon-6,6 and tufted polypropylene fabrics Edel Grass Netherlands... 

Omniturf tufted polypropylene sand-fiUed fabrics Southwest Recreational Industries u.s. 

Playfield Turf tufted polypropylene fabrics Playfield Industries u.s. 

Polytan tufted polypropylene fabrics various Germany... 

Sportilux tufted and knitted nylon and Desso/DLWAG Netherlands/ German... 

Supergrasse tufted polypropylene fabrics Balsam Pacific Austraha... 

Kramer Court sand-fiUed tufted fabrics for tennis Kramer Court ... 

Poly(vinyl acetate) emulsions are used to prime-coat fabrics to improve the adhesion of subsequent coatings or to make them adhere better to plastic film. Plasticized emulsions are appHed, generally by roUer-coating, to the backs of finished mgs and carpets to bind the tufts in place and to impart stiffness and hand. For upholstery fabrics woven from colored yams, PVAc emulsions may be used to bind the tufts of pile fabrics or to prevent sHppage of synthetic yams. 

Some 50% of all nylon is in the form of carpets almost exlusively colored with acid dyes, and around 50% of the carpet manufacturing industry is located in the United States. The acid dyes from Group 1 are those most widely used because they exhibit the rapid diffusion needed to penetrate the bulky yams used in carpets, especially bulk continuous filament yam used in tufted constmctions, with high exhaustion. Their wetfastness properties are generally adequate for most oudets. 

William Eykamp, Ph.D., Adjunct Professor of Chemical Engineering, Tufts University Formerly President, Koch Membrane Systems Member, American Institute of Chemical Engineers, American Chemical Society, American Association for the Advancement of Science, North American Membrane Society, European Society of Membrane Science and Technology (Section 22, Alternative Separation Processes)... 

Amongst hydrocarbon polymers polypropylene has been uniquely successful as a fibre. Its comparatively low cost and excellent wear together with resistance to staining have led to a major use in carpets as the tufting material. It has also found some use for blankets. As softer grades of fibre become available and... 

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