| 摘要 |
1522882 Polyester film composition MITSUBISHI CHEMICAL INDUSTRIES Ltd 16 July 1976 [17 July 1975 18 July 1975 (2)] 29767/76 Heading C3R Polyester film comprises a polyester which is mainly polyethylene terephthalate which includes granular calcium terephthalate anhydride particles of volume shape factor 0À08 to 0À4, given by the formula V/D<3> where D= maximum particle dimension in microns in the projection plane and V=volume of the particle in cubic microns. Such separately prepared particles are more effective for improving abrasion resistance and reducing friction than those conventionally obtained by precipitation with the reaction system. Different preferred relationships of particle size distribution and proportions are given according to whether the film is intended to be metallized or used in an electrical condenser. Reference is made to Specification 1,190,078. |
