| abstract |
(57) [Summary] [Objective] The syndiotactic polystyrene film of the present invention is suitable for industrial use by optimizing the stretching conditions. Substrate with excellent electrical properties, transparency and mechanical strength required for packaging, magnetic tape, capacitors, etc., as well as flatness, printability, heat resistance, abrasion resistance, scratch resistance, etc. Is intended to be provided. [Structure] A polystyrene polymer mainly composed of a syndiotactic structure, which is stretched in at least one axis direction and has a refractive index Nz in the thickness direction of the film of 1.623 or less and a heat shrinkage ratio of 150 ° C. of 3% or less. A film characterized by that. |