Shoe Manufacturers and Repairers
Shoes are made from different materials, above all leather, plastics, e.g., polyurethane, and rubber. Materials vary and, often, the final assembler has no detailed information about the ingredients of the parts that are used in shoe production. The different parts of the shoe are glued together using urethane, neoprene, natural rubber, or other glues. Colophony is occasionally used as a tackifier. Urethane adhesives may contain additives, such as isocyanates, epoxy resins, or phenol-formaldehyde resins. Neoprene glues contain p-tert-butylphenol formaldehyde resin and other additives. Dodecyl mercaptan is used to stop polymerization in neoprene glues. Natural rubber glues are preserved with phenol, formaldehyde, or p-chloro-m-cresol, and may contain triethanolamine. Adhesives and varnishes may contain solvents, such as toluene, xylene, and n-hexane.