Leather, synthetic

The late 1950s saw the emergence of cast elastomers, which led to the development of reaction injection mol ding (RIM) at Bayer AG in Leverkusen, Germany, in 1964 (see Plastics processing). Also, thermoplastic polyurethane elastomers (TPUs) and Spandex fibers (see Fibers, elastomeric) were introduced during this time. In addition, urethane-based synthetic leather (see Leather-LIKEmaterials) was introduced by Du Pont under the trade name Corfam in 1963. 

These polymers, typical of polyamides with fewer than four main chain carbon atoms in the repeating unit, decompose before melting and have to be processed from solution. Several of the polymers may, however, be spun into fibres. Over thirty years ago Courtaulds produced silk-like fibres on an experimental commercial scale from poly-(L-alanine) and from poly-(a-methyl-L-glutamate). The latter material is also said to be in use as a synthetic leather in Japan. The... 

The market is dominated by flexible foam applications (43% in the United States) and rigid and semi-rigid foam (29%). Cast elastomers (4%) and RIM elastomers (3%) have only specialised outlets. The remaining sizeable 21% of the market cover such diverse uses as thermoplastic rubbers, surface coatings, adhesives, sealants and synthetic leathers. 

In PVC, most benzimidazolone pigments are heat stable up to 220°C. They have excellent to outstanding lightfastness. Some representatives are very weather-fast in impact resistant PVC types and in rigid PVC and even withstand long-term weathering. Various benzimidazolone pigments are used, for instance by the automobile industry, in PVC plastisols to lend color to synthetic leather. 

On a more pedestrian level, China s Textile Ministry is promoting the greater use of synthetics for shoes. While there is ample supply of PVC and polyethylene for informal wear ("bubble sandals" in China), the Chinese will aim for the greater use of synthetic leather for more general-purpose footwear. 

Class I. Felts and polymer impregnated felts Class 11. Microporous synthetic leathers Class III. Filled polymer films Class IV. Unfilled textured polymer films... 

Lustre/pearlescent pigments have found wide application in automotive coatings, coloured plastics, synthetic leather, printing inks, ceramic products and cosmetics, e.g. nail polish, lipstick and mascara. 

Caprolactam is used primarily in the manufacture of synthetic fibres and resins (especially nylon 6), bristles, film, coatings synthetic leather, plasticizers and paint vehicles as a cross-linking agent for polyurethanes and in the synthesis of the amino acid lysine (Lewis, 1993). 

According to the 1981-83 United States National Occupational Exposure Survey (NOES, 1997), as many as 125 000 workers in the United States were potentially exposed to dimethylformamide (see General Remarks). Occupational exposures to dimethylformamide may occur in the production of the chemical, other organic chemicals, resins, fibres, coatings, inks and adhesives. Exposure also may occur during use of these coatings, inks, adhesives, in the synthetic leather industry, in the tanning industry and in the repair of aircraft (Ducatman et al., 1986 lARC, 1989). 

In 183 out of 204 employees in a synthetic leather factory, Wang et o/. (1991) found a significant corrrelation between high exposure concentrations of dimethylformamide (25-60 ppm) and elevated serum alanine aminotransferase and creatine phosphokinase levels. Furthermore, high dimethylformamide exposure concentrations were correlated with symptoms such as dizziness, anorexia, nausea and epigastric pain. 

Exposures to dimethylformamide occur during its production and during the production of inks, adhesives, resins, fibres, pharmaceuticals, synthetic leather, and its use as a purification or separation solvent in organic synthesis. It has been detected in ambient air and water. 

Dimethylformamide-induced liver damage among synthetic leather workers. Arch, environ. 

Microfibers -m synthetic leather QEATHER-LIKE MATERIALS] (Vol 15)... 

POROMER1C. A term coined to describe the microporosity, air permeability, and water and abrasion resistance of natural and synthetic leather. The pores decrease in diameter from the inner surface to the outer and thus permit air and water vapor lo leave lire material while excluding water from the outside. Polyester-reinforced urethane resins have been used as leather substitutes with some success, primarily for shoe uppers. 

These polymers commonly are described as PVC plastics or less specifically as vinyl. They are materials that may be either flexible or rigid according to what they are mixed with, and they are used in the manufacture of many familiar articles such as plastic curtains, rainwear, floor tile, synthetic leather goods, upholstery, table mats, phonograph records, insulation, plastic pipes, tubing, and packaging materials. 

Includes thermoplastic urethanes and synthetic leather. Includes paints. 

The first synthetic leather dyes were cationic. Mauveine, discovered by W. H. Perkin, marked the start of the synthetic dye industry. The cationic dyes were characterized by a previously unknown brightness. Nevertheless, the introduction of the new synthetic dyes was not a simple matter. The lightfastness properties were poor. However, the presence of Perkin at the first International Leather Congress in 1897 in London, undoubtedly ensured the breakthrough in the use of synthetic dyes for leather. 

Polyethylene is the most widespread polymer it is used in bags, containers, and wire insulation. Polyvinylchloride is used in the production of containers, plumbing accessories, synthetic leather, and floor tiles, and polypropylene is applied in the fabrication of rugs and containers [196],... 

Amino acids are monomeric units of polypeptides and proteins. They are widely used in the food and chemical industries as flavor enhancers, seasonings and sweeteners e.g. for the improvement of bread quality, also in the production of drugs, cosmetics, synthetic leather and surfactants, in medicine for infusions and as therapeutic agents. Amino acids are produced by chemical synthesis or extraction from protein hydrolyzate. They may be also produced by microbiological methods. 

Poly(trimethylene carbamate) is used in high-quality synthetic leather. It has the structure shown. 

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