A curable resin composition comprising: a compound containing an aliphatic carbon-carbon unsaturated bond; and a compound containing a hydrosilyl group; the compound being at least one compound selected from the group consisting of: a ladder-type silsesquioxane containing an aliphatic carbon-carbon unsaturated bond and having a number-average molecular weight from 500 to 1500 and a molecular weight dispersity (Mw/Mn) from 1.00 to 1.40 as determined by gel permeation chromatography and calibrated with a polystyrene standard; a ladder-type silsesquioxane containing an aliphatic carbon-carbon unsaturated bond, other than the ladder-type silsesquioxane; a linear or branched silicone containing an aliphatic carbon-carbon unsaturated bond; and a cyclic siloxane containing an aliphatic carbon-carbon unsaturated bond; the compound being at least one compound selected from the group consisting of: a ladder-type silsesquioxane containing a hydrosilyl group and having a number-average molecular weight from 500 to 1500 and a molecular weight dispersity (Mw/Mn) from 1.00 to 1.40 as determined by gel permeation chromatography and calibrated with a polystyrene standard; a ladder-type silsesquioxane containing a hydrosilyl group, other than ladder-type silsesquioxane; a linear or branched silicone containing a hydrosilyl group; and a cyclic siloxane containing a hydrosilyl group; the curable resin composition comprising at least one of the ladder-type silsesquioxane and the ladder-type silsesquioxane; and the curable resin composition further comprising an isocyanuric acid compound represented by Formula (d-1): wherein R 31 represents, in each occurrence identically or differently, a monovalent organic group having a carbon atom at a bonding site with the nitrogen atom indicated in the formula, where at least one occurrence of R 31 is a monovalent group containing an aliphatic carbon-carbon unsaturated bond. a compound containing an aliphatic carbon-carbon unsaturated bond; and a compound containing a hydrosilyl group; the compound being at least one compound selected from the group consisting of: a ladder-type silsesquioxane containing an aliphatic carbon-carbon unsaturated bond and having a number-average molecular weight from 500 to 1500 and a molecular weight dispersity (Mw/Mn) from 1.00 to 1.40 as determined by gel permeation chromatography and calibrated with a polystyrene standard; a ladder-type silsesquioxane containing an aliphatic carbon-carbon unsaturated bond, other than the ladder-type silsesquioxane; a linear or branched silicone containing an aliphatic carbon-carbon unsaturated bond; and a cyclic siloxane containing an aliphatic carbon-carbon unsaturated bond; a ladder-type silsesquioxane containing an aliphatic carbon-carbon unsaturated bond and having a number-average molecular weight from 500 to 1500 and a molecular weight dispersity (Mw/Mn) from 1.00 to 1.40 as determined by gel permeation chromatography and calibrated with a polystyrene standard; a ladder-type silsesquioxane containing an aliphatic carbon-carbon unsaturated bond, other than the ladder-type silsesquioxane; a linear or branched silicone containing an aliphatic carbon-carbon unsaturated bond; and a cyclic siloxane containing an aliphatic carbon-carbon unsaturated bond; the compound being at least one compound selected from the group consisting of: a ladder-type silsesquioxane containing a hydrosilyl group and having a number-average molecular weight from 500 to 1500 and a molecular weight dispersity (Mw/Mn) from 1.00 to 1.40 as determined by gel permeation chromatography and calibrated with a polystyrene standard; a ladder-type silsesquioxane containing a hydrosilyl group, other than ladder-type silsesquioxane; a linear or branched silicone containing a hydrosilyl group; and a cyclic siloxane containing a hydrosilyl group; a ladder-type silsesquioxane containing a hydrosilyl group and having a number-average molecular weight from 500 to 1500 and a molecular weight dispersity (Mw/Mn) from 1.00 to 1.40 as determined by gel permeation chromatography and calibrated with a polystyrene standard; a ladder-type silsesquioxane containing a hydrosilyl group, other than ladder-type silsesquioxane; a linear or branched silicone containing a hydrosilyl group; and a cyclic siloxane containing a hydrosilyl group; the curable resin composition comprising at least one of the ladder-type silsesquioxane and the ladder-type silsesquioxane; and the curable resin composition further comprising an isocyanuric acid compound represented by Formula (d-1): wherein R 31 represents, in each occurrence identically or differently, a monovalent organic group having a carbon atom at a bonding site with the nitrogen atom indicated in the formula, where at least one occurrence of R 31 is a monovalent group containing an aliphatic carbon-carbon unsaturated bond.