Tetrakisphenol and non-clathrated curing agent for epoxy resin

A method for curing an epoxy resin comprising a step of mixing a non-clathrated curing agent reacting with an epoxy group of the epoxy resin to cure the resin and a tetrakisphenol compound represented by a general formula (I) as a curing accelerator catalyst with a non-curing epoxy resin,

• wherein X represents (CH2)n, wherein n is 0, 1, 2 or 3, and R1 to R8 each represents hydrogen, a lower alkyl, a phenyl optionally substituted with halogen or C1-C6 alkyl, a halogen or a C1-C6 alkoxy, and
• wherein the content of said tetrakisphenol compound represented in formula (I) is a range from 0.001 to 0.025 mole based on 1 mole of the epoxy group.

A method for curing an epoxy resin composition comprising the steps of:

• a clathrate comprising a tetrakisphenol compound represented by a general formula (I) and a compound reacting with an epoxy group of the epoxy resin to cure the resin is added and mixed to a non-curing epoxy resin, and then the mixture is heated to a predetermined temperature,
• wherein X represents (CH2)n, wherein n is 0, 1, 2 or 3, and R1 to R8 each represents hydrogen, a lower alkyl, a phenyl optionally substituted with halogen or C1-C6 alkyl, a halogen or a C1-C6 alkoxy,
• wherein the content of the tetrakisphenol compound represented by general formula (I) in the clathrate is from 0.001 to 0.025 mole based on 1 mole of the epoxy group.