Photocurable prepreg composition and production method thereof

A method for producing a photocurable prepreg composition comprising prepolymerizing by irradiating a composition which comprises

• an unsaturated polyester resin, an epoxy(meth)acrylate;
• or mixture thereof;
• at least two photopolymerization initiators with photosensitivity in different wavelength ranges comprising
• (A) a photopolymerization initiator with photosensitivity in a visible range of wavelengths of 500 nm or more or in a near infrared range comprising (1) a cationic dye represented by formula (1):
• D+[Circlesolid]A− (1)
• wherein D+ represents a dye cation with photosensitivity in a visible or a near infrared range and which is derived from a member selected from the group consisting of methine, polymethine, cyanine, xanthene, oxazine, thiazine, arylmethane, and pyrylium:
• and A− represents an anion and (2) an organo borate represented by formula (2):
• wherein Z+ represents a cation;
• each R1, R2, R3 and R4 represents an alkyl group, an aryl group, an acyl group, an aralkyl group, an alkenyl group, an alkynyl group, a silyl group, a heterocyclic group, or a halogen atom;
• and
• (B) a photopolymerization initiator with photosensitivity in a visible range of wavelengths of less than 500 nm and/or in an ultraviolet range;
• and
• an inorganic or organic fiber-reinforcing material, an inorganic or an organic filler or a mixture thereof, with visible light of a wavelength of 500 nm or more or with near infrared light.

A method for producing a cured product of a photocurable prepreg composition comprising prepolymerizing by irradiating a composition which comprises

• an unsaturated polyester resin, an epoxy(meth)acrylate;
• or mixture thereof;
• at least two photopolymerization initiators with photosensitivity in different wavelength ranges comprising
• (A) a photopolymerization initiator with photosensitivity in a visible range of wavelengths of 500 nm or more or in a near infrared range comprising (1) a cationic dye represented by formula (1):
• D+[Circlesolid]A− (1)
• wherein D+ represents a dye cation with photosensitivity in a visible or a near infrared range and which is derived from a member selected from the group consisting of methine, polymethine, cyanine, xanthene, oxazine, thiazine, arylmethane, and pyrylium;
• and A− represents an anion and (2) an organo borate represented by formula (2):
• wherein Z+ represents a cation;
• each R1, R2, R3 and R4 represents an alkyl group, an aryl group, an acyl group, an aralkyl group, an alkenyl group, an alkynyl group, a silyl group, a heterocyclic group, or a halogen atom;
• and
• (B) a photopolymerization initiator with photosensitivity in a visible range of wavelengths of less than 500 nm and/or in an ultraviolet range;
• and
• an inorganic or organic fiber/reinforcing material, an inorganic or an organic filler or a mixture thereof;
• and
• which composition is treated with light of a specific wavelength for at least one photoinitiator with photosensitivity to the specific wavelength such that at least one photopolymerization initiator and radical-polymerizable unsaturated groups remain partially in said resin to produce a prepreg composition and irradiating the prepreg composition with light having a specific wavelength to which a photopolymerization initiator present in the prepreg composition is photosensitive.

A cured product of a photocurable prepreg composition which is obtained by installing or molding and irradiating a photocurable prepreg composition which comprises

• an unsaturated polyester resin, an epoxy(meth)acrylate;
• or mixture thereof;
• at least two photopolymerization initiators with photosensitivity in different wavelength ranges comprising
• (A) a photopolymerization initiator with photosensitivity in a visible range of wavelengths of 500 nm or more or in a near infrared range comprising (1) a cationic dye represented by formula (1):
• D+[Circlesolid]A− (1)
• wherein D+ represents a dye cation with photosensitivity in a visible or a near infrared range and which is derived from a member selected from the group consisting of methine, polymethine, cyanine, xanthene, oxazine, thiazine, arylmethane, and pyrylium;
• and A− represents an anion and (2) an organo borate represented by formula (2):
• wherein Z+ represents a cation;
• each R1, R2, R3 and R4 represents an alkyl group, an aryl group, an acyl group, an aralkyl group, an alkenyl group, an akynyl group, a silyl group, a heterocyclic group, or a halogen atom;
• and
• (B) a photopolymerization initiator with photosensitivity in a visible range of wavelengths of less than 500 nm and/or in an ultraviolet range;
• and
• an inorganic or organic fiber reinforcing material, an inorganic or an organic filler or a mixture thereof;
• and
• which composition is treated with light of a specific wavelength for at least one photoinitiator with photosensitivity to the specific wavelength such that at least one photopolymerization initiator and radical-polymerizable unsaturated groups remain partially in said resin, to produce a prepreg composition, which prepreg composition is irradiated with light having a specific wavelength to which a photopolymerization initiator present in the prepreg composition is photosensitive.