Active energy ray-curable, organopolysiloxane resin composition, light-transmitting component, and method for manufacturing the light-transmitting component

1. An active energy ray-curable organopolysiloxane resin composition comprising:

(A) 100 parts by weight of an epoxy-containing organopolysiloxane resin represented by the following siloxane unit formula (1):

(R 1 R 2 R 3 SiO 1/2 ) a (R 4 R 5 SiO 2/2 ) b (R 6 SiO 3/2 ) c (SiO 4/2 ) d   (1)

where R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 are organic groups selected from univalent aliphatic hydrocarbon groups with 1 to 6 carbon atoms, univalent aromatic hydrocarbon groups with 6 to 10 carbon atoms, and epoxy-containing univalent hydrocarbon groups, wherein in one molecule the siloxane units with epoxy-containing univalent hydrocarbon groups constitute 2 to 50 mole %, the univalent aromatic hydrocarbon groups with 6 to 10 carbon atoms constitute more than 15 mole % of all organic groups, and where the following conditions are satisfied: a+b+c+d=1; “a” on average satisfies the following condition; 0≦a<0.4; “b” on average satisfies the following condition; 0<b<0.5; “c” on average satisfies the following condition; 0<c<1; “d” on average satisfies the following condition; 0≦d<0.4; “b” and “c” are bound by the following condition; 0.01≦b/c≦0.3; and wherein the total content of alkoxy groups and hydroxyl groups on silicon atoms of the epoxy-containing organopolysiloxane resin is no more than 2 mole % of all substituents on silicon atoms;

(B) 0.05 to 20 parts by weight of a photopolymerization initiator; and

(C) 0 to 5000 parts by weight of an organic solvent.

2. The active energy ray-curable organopolysiloxane resin composition according to claim 1 for use as a cured body in the form of a film.

3. The active energy ray-curable organopolysiloxane resin composition according to claim 1 for use as a light-transmitting component.

4. The active energy ray-curable organopolysiloxane resin composition according to claim 3 wherein said light-transmitting component is an optical waveguide.

5. The active energy ray-curable organopolysiloxane resin composition according to claim 1 , wherein said active-energy rays are ultraviolet rays.

6. The active energy ray-curable organopolysiloxane resin composition according to claim 1 , wherein the epoxy-containing organopolysiloxane resin represented by the siloxane unit formula (1) is selected from the group of organopolysiloxane resins composed of (Me 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 1 SiO 3/2 ) units; (Me 3 SiO 1/2 ), (Me 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 1 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (PhSiO 3/2 ), (E 1 SiO 3/2 ) and (SiO 4/2 ) units; (Me 2 SiO 2/2 ), (PhSiO 3/2 ), (MeSiO 3/2 ), and (E 1 SiO 3/2 ) units; (Ph 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 1 SiO 3/2 ) units; (MePhSiO 2/2 ), (PhSiO 3/2 ), and (E 1 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 2 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 3 SiO 3/2 )units;(Me 2 SiO 2/2 ), (Ph 2 SiO 2/2 ), and (E 1 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (Ph 2 SiO 2/2 ), and (E 3 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 4 SiO 3/2 ) units; (MeViSiO 2/2 ), (PhSiO 3/2 ) and (E 3 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (PhSiO 3/2 ), (MeSiO 3/2 ), and (E 3 SiO 3/2 ) units; (Ph 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 3 SiO 3/2 ) units; (Me 2 ViSiO 1/2 ), (Me 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 1 SiO 3/2 ) units; (Me 3 SiO 1/2 ), (Ph 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 1 SiO 3/2 ) units; (Me 3 SiO 1/2 ), (Me 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 3 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (PhSiO 3/2 ), (E 3 SiO 3/2 ), and (SiO 2 ) units; (Me 2 SiO 2/2 ), (Ph 2 SiO 2/2 ), (E 1 SiO 3/2 ), and (SiO 2 ) units; (Me 3 SiO 1/2 ), (Me 2 SiO 2/2 ), (PhSiO 3/2 ), (E 1 SiO 3/2 ), and (SiO 2 ) units; and (Me 3 SiO 1/2 ), (Me 2 SiO 2/2 ), (PhSiO 3/2 ), (E 3 SiO 3/2 ), and (SiO 2 ) units; wherein Me designates a methyl group, Vi designates a vinyl group, Ph designates a phenyl group, E 1 designates a 3-(glycidoxy)propyl group, E 2 designates a 2-(glycidoxycarbonyl)propyl group, E 3 designates a 2-(3,4-epoxycyclohexyl)ethyl group, and E 4 designates 2(4-methyl-3,4-epoxycyclohexyl) propyl group.

7. A light-transmitting component obtained by curing (A) an epoxy-containing organopolysiloxane resin represented by the following siloxane unit formula (1):

(R 1 R 2 R 3 SiO 1/2 ) a (R 4 R 5 SiO 2/2 ) b (R 6 SiO 3/2 ) c (SiO 4/2 ) d   (1)

where R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 are organic groups selected from univalent aliphatic hydrocarbon groups with 1 to 6 carbon atoms, univalent aromatic hydrocarbon groups with 6 to 10 carbon atoms, and epoxy-containing univalent hydrocarbon groups, wherein in one molecule the siloxane units with epoxy-containing univalent hydrocarbon groups constitute 2 to 50 mole %, the univalent aromatic hydrocarbon groups with 6 to 10 carbon atoms constitute more than 15 mole % of all organic groups, and where the following conditions are satisfied: a+b+c+d=1; “a” on average satisfies the following condition; 0≦a<0.4; “b” on average satisfies the following condition; 0<b<0.5; “c” on average satisfies the following condition; 0<c<1; “d” on average satisfies the following condition; 0≦d<0.4; “b” and “c” are bound by the following condition; 0.01≦b/c≦0.3; and wherein the total content of alkoxy groups and hydroxyl groups on silicon atoms of the epoxy-containing organopolysiloxane resin is no more than 2 mole % of all substituents on silicon atoms under effect of irradiation with active energy rays in the presence of (B) a photopolymerization initiator where component (B) is used in an amount of 0.05 to 20 parts by weight for each 100 parts by weight of component (A).

8. The light-transmitting component according to claim 7 , wherein said light-transmitting component is an optical waveguide.

9. The light-transmitting component according to claim 8 , wherein said optical waveguide is made in the form of a film.

10. The light-transmitting component according to claim 7 , wherein said active-energy rays are ultraviolet rays.

11. The light-transmitting component according to claim 7 , wherein the epoxy-containing organopolysiloxane resin represented by the siloxane unit formula (1) is selected from the group of organopolysiloxane resins composed of (Me 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 1 SiO 3/2 ) units; (Me 3 SiO 1/2 ), (Me 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 1 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (PhSiO 3/2 ), (E 1 SiO 3/2 ) and (SiO 4/2 ) units; (Me 2 SiO 2/2 ), (PhSiO 3/2 ), (MeSiO 3/2 ), and (E 1 SiO 3/2 ) units; (Ph 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 1 SiO 3/2 ) units; (MePhSiO 2/2 ), (PhSiO 3/2 ), and (E 1 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 2 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 3 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (Ph 2 SiO 2/2 ), and (E 1 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (Ph 2 SiO 2/2 ), and (E 3 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 4 SiO 3/2 ) units; (MeViSiO 2/2 ), (PhSiO 3/2 ), and (E 3 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (PhSiO 3/2 ), (MeSiO 3/2 ), and (E 3 SiO 3/2 ) units; (Ph 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 3 SiO 3/2 ) units; (Me 2 ViSiO 1/2 ), (Me 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 1 SiO 3/2 ) units; (Me 3 SiO 1/2 ), (Ph 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 1 SiO 3/2 ) units; (Me 3 SiO 1/2 ), (Me 2 SiO 2/2 ), (PhSiO 3/2 ), and (E 3 SiO 3/2 ) units; (Me 2 SiO 2/2 ), (PhSiO 3/2 ), (E 3 SiO 3/2 ), and (SiO 2 ) units; (Me 2 SiO 2/2 ), (Ph 2 SiO 2/2 ), (E 1 SiO 3/2 ), and (SiO 2 ) units; (Me 3 SiO 1/2 ), (Me 2 SiO 2/2 ), (PhSiO 3/2 ), (E 1 SiO 3/2 ), and (SiO 2 ) units; and (Me 3 SiO 1/2 ), (Me 2 SiO 2/2 ), (PhSiO 3/2 ), (E 3 SiO 3/2 ), and (SiO 2 ) units; wherein Me designates a methyl group, Vi designates a vinyl group, Ph designates a phenyl group, E 1 designates a 3-(glycidoxy)propyl group, E 2 designates a 2-(glycidoxycarbonyl)propyl group, E 3 designates a 2-(3,4-epoxycyclohexyl)ethyl group, and E 4 designates 2-(4-methyl-3,4-epoxycyclohexyl) propyl group.

12. A method of manufacturing a light-transmitting component, comprising the steps of: applying the active energy ray-curable organopolysiloxane resin composition of claim 1 onto a substrate; and curing the applied composition by irradiating it with active-energy rays.

13. A method of manufacturing an optical waveguide, comprising the steps of: 1) forming a lower cladding layer by applying the active energy ray-curable organopolysiloxane resin composition of claim 1 onto a substrate and by curing the applied material by irradiating it with active-energy rays; 2) forming a core layer by applying the active energy ray-curable organopolysiloxane resin composition of claim 1 onto the lower cladding layer and by curing the applied layer by irradiating it with active energy rays; optionally, processing the core layer into a desired shape; and 3) forming an upper cladding layer by applying the active energy ray-curable organopolysiloxane resin composition of claim 1 onto the core layer, and curing the applied material by irradiating it with active-energy rays.

14. The method of manufacturing an optical waveguide according to claim 13 , wherein the refractive index of the cured body is greater than the refractive index of the cladding layer.