Epoxy Resin, Method for Producing Same and Epoxy Resin Composition Thereof
An epoxy resin represented by general formula (I), which satisfies numerical formula (1) mentioned below and comprises hydrolytic halogen of 0.05 wt. % or less, said epoxy resin being produced by the procedure as follows: after dissolving 0.8 to 1.3 mole of epihalohydrin to 1 mole of divalent phenol in a solvent, a pre-reaction is performed over 30 to 70 minutes by adding dropwise 0.25-0.35 mole of 30˜50% aqueous solution of alkali metal hydroxide over 30 to 70 minutes thereto, and thereafter, 0.65-0.75 mole of the remaining 30˜50% aqueous solution of alkali metal hydroxide is added dropwise over about 1 hour to complete the reaction over 1 to 3 hours. wherein n is an integer of 0 or more; A 1 and A 2 are residue of divalent phenol, and can be same or different; both R 1 and R 2 are H or wherein, X: epoxy equivalent (g/eq); Y: phenolic hydroxyl group equivalent (g/eq).
1 . An epoxy resin represented by general formula (I), which satisfies numerical formula (1) below and comprises hydrolytic halogen of 0.05 wt. % or less, said epoxy resin being produced by the procedure as follows: after dissolving 0.8 to 1.3 mole of epihalohydrin to 1 mole of divalent phenol in a solvent, a pre-reaction is performed over 30 to 70 minutes by adding dropwise 0.25-0.35 mole of 30˜50% aqueous solution of alkali metal hydroxide over 30 to 70 minutes thereto, and thereafter, 0.65-0.75 mole of the remaining 30˜50% aqueous solution of alkali metal hydroxide is added dropwise over approximately 1 hour to complete the reaction over approximately 1 to 3 hours.
wherein n is an integer of 0 or more;
A 1 and A 2 are residue of divalent phenol, and can be same or different;
both R 1 and R 2 are H or
wherein,
X: epoxy equivalent (g/eq);
Y: phenolic hydroxyl group equivalent (g/eq).
2 . The epoxy resin of claim 1 wherein the divalent phenol is bisphenol.
3 . The epoxy resin of claim 1 wherein the epoxy equivalent of the resin is 3000 g/eq or less and the phenolic hydroxyl group equivalent of the resin is 5000 g/eq or less.
4 . An epoxy resin composition containing an epoxy resin according to claim 1 as an essential component.