| 摘要 |
<p>A separator, a packaging material, or a pressure-sensitive adhesive tape base material is disclosed, which each has a releasing agent layer formed on part or the whole of at least one side of a substrate which, when examined by thermomechanical analysis (thermomechanometry), has specific values of the average coefficient of linear expansion (1/ DEG Cx10<-3>) in the machining direction and the traversing direction for each temperature range. When the releasing agent layer is composed of a silicone releasing agent, the substrate comprises a plastic film having an antioxidant content, an antistatic agent content, a lubricant content, and an ultraviolet absorber content of 0.4% by weight or lower each. The separator, packaging material, or the pressure-sensitive adhesive tape base material, when used under conditions which require heat resistance, is free from the problem that thermal-shrinkage wrinkles generate to result in an impaired appearance. In the case where the releasing agent layer of the separator, packaging material, or the pressure-sensitive adhesive tape base material is composed of a silicone releasing agent, this releasing agent layer is prevented from reducing the adhesion performance of the pressure-sensitive adhesive layer to be in contact therewith. <IMAGE></p> |
