| 摘要 |
PROBLEM TO BE SOLVED: To obtain an epoxy resin compsn. improved in heat resistance and adhesive properties by compounding a bisphenol epoxy resin, a specific epoxy resin, and a cationic-polymn. catalyst. SOLUTION: The compsn. comprising 100wt.% bisphenol epoxy resin and 5-50wt.% epoxy resin represented by formula I (wherein R is a group represented by formula II; a+b+c is on average 15; and n is 1-4) in an amount of 100 pts.wt. is compounded with 1-6 pts.wt. cationic-polymn. catalyst and, if necessary, with an ion exchanger in an amt. of 2-8 times that of the catalyst, a filler, and a coupling agent, thus giving an epoxy resin compsn. A disk substrate 4 is obtd. by forming, on one side of a plastic substrate 1, a recording layer 2 and then a 5-10μm-thick protective layer 3. Two disk substrates 4 thus prepd. are faced to each other with their recording layers 2 kept inside, bonded to each other with an adhesive layer 5 formed from the resin compsn., and irradiated with an energy ray of 50-1,000J/cm<2> to subject the compsn. to cationic polymn. |
