本发明的目的在于提供一种作为环氧树脂的硬化剂,具有合适的使用寿命,且具有优良的保存安定性,并且硬化后所得到的环氧树脂硬化物的耐水性、硬度优良的环氧树脂硬化剂。本发明其特征系含有在相对于硫醇基为���位的碳原子上具有取代基的2级或3级的支链硫醇化合物之环氧树脂硬化剂、及含有多元环氧化合物与前述环氧树脂硬化剂之环氧树脂组成物。

Disclosed is an epoxy resin curing agent which has a suitable working life as a curing agent for epoxy resins, while exhibiting good storage stability. In addition, an epoxy resin cured product cured by this epoxy resin curing agent is good in water resistance and hardness. Specifically disclosed is an epoxy resin curing agent containing a secondary or tertiary branched thiol compound having a substituent at a carbon atom in the a-position to a thiol group. Also specifically disclosed is an epoxy resin composition characterized by containing a polyvalent epoxy compound and such an epoxy resin curing agent.