PURPOSE: To obtain a prepreg which gives a molding that can be made lightweight because of low density and that is improved in strength, by laminating a fibrous base material impregnated with a curable resin and a curing agent and/or a thermosetting resin on both sides of a specified fibrous base material.
CONSTITUTION: 100 pts.wt. component (A) comprising a curable resin and a curing agent and/or a thermosetting resin is mixed with 3-50 pts.wt. expansive thermoplastic resin particles (B) having a diameter of 1μm to 1mm and/or 0.5-20 pts.wt. thermally decomposable foaming agent to give a mixture. 100 pts.wt. fibrous base material (C) having a weight per unit area of 25-300g/m2 is impregnated with 50-500 pts.wt. of the mixture to give a fibrous base material (D) having a weight per unit area of 100-1000g/m2. 100 pts.wt. component C is impregnated with 20-500 pts.wt. component A to give a fibrous base material (E) having a weight per unit area of 30-300g/m2. Component E is laminated on both sides of component D.
HANAWA YOSHINORI
OYA TOMOAKI
KAWAMOTO KAZUHIKO
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