| 摘要 |
PURPOSE:To obtain the entitled film superior in resistance to heat and dimensional stability, and not causing waving phenomenon, by using a specified polyether imide film. CONSTITUTION:Polyether imide having >=0.2d/g intrinsic viscosity measured in m-cresol at 25 deg.C and >=190 deg.C glass transition point is dissolved in a solvent, such as chloroform, and formed into a film having <=200mum thickness to obtain an electrophotographic copying film having <=0.8% heat shrinkage coefft. at 180 deg.C and <=15X10<-3> absolute value of the difference between longitudinal and lateral refractive indices. This film does not cause discoloration and deterioration of strength even after long period storage, and it can produce a large mass of labels and stickers in a short time by high-speed copying. |
