| 摘要 |
PURPOSE:To obtain an electric laminated sheet which is excellent in hygroscopicity, mechanical strength, punching processability, and heat resistance by a method wherein radial polymerized resin having a specific Tg (glass transition temperature) is impregnated in cellulose fiber base, and polymerization reaction is restrained by a radical polymerization inhibitor in hardening. CONSTITUTION:As a residual polymerization resin, unsaturated polyester resin, vinyl ester resin, diallyl phthalate resin, etc. of which Tg excess 80 deg.C are used. In order to restrain radical reaction of radical polymerization resin in hardening, a method or the like in which after treating cellulose fiber base with treating liquid preliminarily containing radical reaction inhibitor, it is impregnated with radical polymerization resin, is laminated, and is hardened, are used. Thus Tg of the radical polymerization resin of an obtained electric laminate is made 90 to 50% of the Tg of radical polymerization hardened resin. As the radical polymerization reaction inhibitor, phenol resin, phenol groups, polyphenol group, quinone group, hydroquinone group, and nitro compound are used. As treating liquid of the base, melamine resin, guanamine resin, etc. are preferable. |
