Curable resin composition and cured product thereof, sealing material for optical semiconductor, die bonding material, and optical semiconductor light-emitting element

A curable resin composition, comprising

• (A) an epoxy compound having three or more epoxy groups in one molecule, the epoxy compound comprising an organopolysiloxane containing a compound represented by the following formula (1) or a compound represented by the following formula (2):
• in which R1 each independently represents a substituted or unsubstituted monovalent hydrocarbon group having a carbon number of 1 to 10;
• R2 each independently represents an epoxy group-containing organic group;
• R3 each independently represents R1 or R2;
• a each independently represents an integer of 2 or more;
• b each independently represents an integer of 0 or more;
• and X represents a group represented by the following formula (3):
• —Y—Z—Y— (3)
• where Y each independently represents an —O— bond or a divalent hydrocarbon group having a carbon number of 1 to 6;
• and Z represents a group represented by the following formula (4):
• —(R42SiO)c—(R4nQ2-nSiO)d—SiR42— (4)
• where R4 each independently represents a substituted or unsubstituted monovalent hydrocarbon group having a carbon number of 1 to 10:
• c represents an integer of 0 or more:
• d represents an integer of 0 or more:
• n represents 0 or 1;
• and Q represents a group represented by the following formula (5):
• —P0—P1 (5)
• where P0 represents any of an —O— bond, a divalent hydrocarbon group having a carbon number of 1 to 10 and optionally having ether bond, or ester bond, and a substituted or unsubstituted dimethylsiloxy group;
• and P1 represents any of a methyl group, a trimethylsilyl group, and a group represented by the following formula (6) or the following formula (7):
• where R1, R2, R3, a, and b are the same as R1, R2, R3, a, and b in the formula (1) and the formula (2);
• (B-1) an optional active hydrogen compound selected from the group consisting of phenols having at least one phenol group in one molecule;
• and
• (B-2) an active hydrogen compound selected from the group consisting of monosilanes having at least one hydrosilyl group in one molecule and polysiloxanes having at least one hydrosilyl group in one molecule.