To obtain FRP, which is excellent in resistances to acid, organic solvent and alkali, by subjecting a composition comprising a resin component wherein a isophthalic acid-based unsaturated polyester resin is diluted with a styrene monomer, a fibrous reinforcing material, and a photopolymerization initiator, to irradiation with light for curing.
The resin composition, which comprises a resin component obtained by diluting 100 pts.wt. (hereinafter referred to simply as pts.) of a resin composed of an isophthalic acid-based unsaturated polyester resin and/or a vinyl ester made of an oligomer of formula I (wherein (n) is 1 to 6) and/or formula II (wherein (n) is 1 to 5) with a styrene monomer and/or (meth)acrylic monomer preferably used in an amount of 10 to 250 pts., and 0 to 200 pts. of a fibrous reinforcing material and/or filler, is irradiated with light and cured. It is preferred that the prepreg obtained by B-staging the resin composition is subjected to light irradiation and cured. It is also preferred that the photopolymerization initiator has sensitivity to light within an arbitrary region including from a UV light region to a near infrared light region.
OTANI KAZUO
MIURA KENJI
SENDAI HIDEKI
KAMATA HIROTOSHI
SHOWA DENKO KK