Curatives for epoxy resin, curing accelerator, and epoxy resin composition

Abstract

The present invention has an object to provide curatives for epoxy resins and curing accelerators for epoxy resins, which both have improved subliming and decomposing properties and which, when mixed with an epoxy resin, enable the mixture to be greatly improved in thermal stability that is extremely important for the control of a curing reaction and to have a prolonged pot life (stability as a one-pack mixture comprising the epoxy resin, curative, etc.) and improved curability at low temperatures. The curative is characterized by being a clathrate comprising a tetrakisphenol compound represented by a general formula [I]; wherein X represents (CH 2 )n, wherein n is 0, 1, 2 or 3, and R 1 to R 8 each represents hydrogen, a lower alkyl, optionally-substituted phenyl, halogeno or a lower alkoxy, and the curing accelerator is characterized by being a clathrate comprising a tetrakisphenol compound represented by the general formula [I] shown above and a compound accelerating the curing of a compound which reacts with the epoxy group of an epoxy resin to cure the resin.

What is claimed is:  
     
         1 . Curatives for epoxy resins characterized by being a clathrate comprising a tetrakisphenol compound represented by a general formula [I];  
       
         
           
           
               
               
           
         
       
       wherein X represents (CH 2 )n, wherein n is 0, 1, 2 or 3, and R 1  to R 8  each represents hydrogen, a lower alkyl, optionally-substituted phenyl, halogeno or a lower alkoxy, and a compound which reacts with the epoxy group of an epoxy resin to cure the resin.  
     
     
         2 . Curing accelerators for epoxy resins characterized by being a clathrate comprising a tetrakisphenol compound represented by a general formula [I];  
       
         
           
           
               
               
           
         
       
       wherein X represents (CH 2 )n, wherein n is 0, 1, 2 or 3, and R 1  to R 8  each represents hydrogen, a lower alkyl, optionally-substituted phenyl, halogeno or a lower alkoxy, and a compound accelerating the curing of a compound which reacts with the epoxy group of an epoxy resin to cure the resin.  
     
     
         3 . Epoxy resin compositions characterized by containing the clathrate comprising a tetrakisphenol compound represented by a general formula [I] and a compound which reacts with the epoxy group of an epoxy resin to cure the resin according to  claim 1  and/or the clathrate comprising a tetrakisphenol compound represented by a general formula [I] and a compound accelerating the curing of a compound which reacts with the epoxy group of an epoxy resin to cure the resin according to  claim 2 .  
     
     
         4 . Epoxy resin compositions characterized by containing a curative which reacts with the epoxy group of an epoxy resin to cure the resin and a tetrakisphenol compound represented by a general formula [I];  
       
         
           
           
               
               
           
         
       
       wherein X represents (CH 2 )n, wherein n is 0, 1, 2 or 3, and R 1  to R 8  each represents hydrogen, a lower alkyl, optionally-substituted phenyl, halogeno or a lower alkoxy, in an amount of from 0.001 to 0.1 mole based on 1 mole of the epoxy groups.  
     
     
         5 . Epoxy resin compositions characterized by containing the clathrate according to  claim 1  which which comprises a tetrakisphenol compound represented by a general formula [I] and a compound which reacts with the epoxy group of an epoxy resin to cure the resin and the clathrate according to  claim 2  which comprises a tetrakisphenol compound represented by a general formula [1] and a compound accelerating the curing of a compound which reacts with the epoxy group of an epoxy resin to cure the resin, wherein the content of the clathrate in the resin composition is in a range of from 0.001 to 0.1 mole based on 1 mole of the epoxy groups, respectively.