Epoxy resin composition, cured object obtained therefrom, and light-emitting diode

摘要

Provided are an epoxy resin composition including acid anhydrides (A) and epoxy resins (B), in which: (a) cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride accounts for 50 to 90 mass % of the acid anhydrides (A); (b) an alicyclic epoxy resin compound accounts for 30 to 90 mass % of the epoxy resins (B) and an epoxy resin compound represented by the following general formula (1) accounts for 10 to 50 mass % of the epoxy resins (B); and (c) contents of the acid anhydrides (A) and the epoxy resins (B) are such that a blending equivalent ratio between the acid anhydrides and the epoxy resins ranges from 0.4 to 0.7, a cured product of the composition, and a light-emitting diode. The epoxy resin composition has the following characteristics. That is, (1) the composition has a low viscosity after the mixing, a low degree of viscosity increase in standing at room temperature, and excellent workability, (2) the composition has satisfactory curability even when no curing accelerator is added, and (3) a cured product is colorless and transparent, has crack resistance, and changes its color to a small extent with long-term light irradiation and heating. The composition is suitable for an encapsulant for a photoelectric conversion element such as a blue LED or white LED. (In the formula, R's each independently represent a hydrogen atom or a methyl group, m represents an integer of 1 to 3, and n represents an integer of 2 to 8.)

主权项

1. An epoxy resin composition, comprising:
acid anhydrides (A); and epoxy resins (B), wherein: (a) cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride accounts for 50 to 90 mass % of the acid anhydrides (A) and the remainder being hexahydrophthalic anhydride and methylhexahydrophthalic anhydride; (b) the epoxy resins (B) consists of 76 to 90 mass % of 3,4-epoxycyclohexylmethyl-3′,4′-epoxycyclohexanecarboxylate and 10 to 24 mass % of hexane-1,6-diglycidyl ether; and (c) contents of the acid anhydrides (A) and the epoxy resins (B) are such that a blending equivalent ratio between the acid anhydrides and the epoxy resins represented by the following formula (2) ranges from 0.44 to 0.59: blending equivalent ratio between acid anhydrides and epoxy resins=(X+Y)/Z (2) where X represents the functional group number of acid anhydride groups in the acid anhydrides (A), Y represents the functional group number of carboxyl groups in the acid anhydrides (A), and Z represents the functional group number of epoxy groups in the epoxy resins (B).