| 摘要 |
PURPOSE:To obtain a release film which is resistant to breaking when released from an FRP molding after molding and can be repeatedly used, by incorporating specified fine silicone resin particles in a biaxially oriented polyester film. CONSTITUTION:A film obtained by incorporating 0.03-1.0wt% fine silicone resin particles comprising a trifunctional organosilicone at lest 80wt% of the structural units of which have a composition of CH2.SiO3/2 and having a volume shape factor of 0.2-0.52 and a mean particle diameter of 0.3-4.0mu in a biaxially oriented polyester film. As the polyester film, for example, a film having an alkylene terephthalate and/or an alkylene naphthalate as the principal structural components is desirable. The polyester in which the fine silicone resin particles are dispersed is preferably prepared by adding the particles to the reaction system in the initial stage of polycondensation, say, before the intrinsic viscosity reaches about 0.3. |
