Highly soluble tris-(2, 3-epoxypropyl)-isocyanurate and method for producing same
There is provided an epoxy composition which has difficulty in precipitating a crystal during storage, is homogeneous and can be stored for a long period; and a cured product of the composition having excellent transparency, heat resistance, and light resistance can be obtained on curing. An α-type tris-(2,3-epoxypropyl)-isocyanurate crystal including β-type tris-(2,3-epoxypropyl)-isocyanurate in the crystal in a ratio of 2% by mass to 15% by mass. A method for producing the α-type tris-(2,3-epoxypropyl)-isocyanurate crystal including step (i) separating β-type tris-(2,3-epoxypropyl)-isocyanurate contained in a tris-(2,3-epoxypropyl)-isocyanurate solution from the solution as a solid to obtain a crystal with an increased content ratio of α-type tris-(2,3-epoxypropyl)-isocyanurate.
1. A curable composition comprising:
an α-type tris-(2,3-epoxypropyl)-isocyanurate crystal comprising β-type tris-(2,3-epoxypropyl)-isocyanurate in the crystal in a ratio of 2% by mass to 7% by mass, wherein the crystal has a particle diameter of 1 μm to 500 μm; and
a carboxylic acid anhydride in a ratio of 0.5 molar equivalent to 1.5 molar equivalent relative to 1 molar equivalent of the crystal, or
a cationic curable compound in a ratio of 0.2 molar equivalent to 5 molar equivalent relative to 1 molar equivalent of the crystal,
wherein the curable composition has a solid content concentration of 1% by mass to 99% by mass, and
wherein when left to stand for one week at room temperature, the curable composition remains clear with no precipitation of tris-(2,3-epoxypropyl)-isocyanurate from the curable composition.
2. A cured product formed by attaching the curable composition according to claim 1 to a substrate and curing the curable composition by heating or light irradiation.
3. The cured product according to claim 2 , wherein the attaching to the substrate is carried out by application, filling, adhesion, or impregnation.
4. The curable composition according to claim 1 , wherein the curable composition is liquid, transparent and homogeneous.
5. The curable composition according to claim 1 , wherein the carboxylic acid anhydride is present, and wherein the carboxylic acid anhydride is liquid at room temperature and is selected from the group consisting of 3-methyl-cyclohexane dicarboxylic acid anhydride, 4-methyl-cyclohexane dicarboxylic acid anhydride, and a mixture of 3-methyl-cyclohexane dicarboxylic acid anhydride and 4-methyl-cyclohexane dicarboxylic acid anhydride.
6. A method for producing a curable composition comprising
mixing an α-type tris-(2,3-epoxypropyl)-isocyanurate crystal comprising β-type tris-(2,3-epoxypropyl)-isocyanurate in the crystal in a ratio of 2% by mass to 7% by mass and the crystal having a particle diameter of 1 μm to 500 μm, and
a carboxylic acid anhydride in a ratio of 0.5 molar equivalent to 1.5 molar equivalent relative to 1 molar equivalent of the crystal, or
a cationic curable compound in a ratio of 0.2 molar equivalent to 5 molar equivalent relative to 1 molar equivalent of the crystal,
wherein the curable composition has a solid content concentration of 1% by mass to 99% by mass, and
wherein when left to stand for one week at room temperature, the curable composition remains clear with no precipitation of tris-(2,3-epoxypropyl)-isocyanurate from the curable composition.