FOAMED THERMOPLASTIC FILMS HAVING A LEATHER-LIKE GRAIN

摘要

1381028 Surface treatment of foamed films IMPERIAL CHEMICAL INDUSTRIES Ltd 22 May 1973 [2 June 1972 29 Sept 1972] 25861/72 and 45064/72 Heading C3C A leather-like grain is formed on a foamed film of a synthetic thermoplastic resin by passing the film around a cylindrical surface having a radius of less than 1 cm. so that the film is bent through an angle of 90-180 degrees. The surface of the film adjacent the surface is thereby compressed and wrinkled, due to the destruction of part of the cellular structure. The surface may be the rounded edge of a plate. The bent film may be bent in the opposite direction by repeating the above process. In the example an open-celled foamed film of a mixture of low and high density polyethylenes and carbon black was treated as above.