Cresol novolac epoxy resin containing phosphorus in preparation

The present invention is a method for producing a phosphorus-containing cresol novolac epoxy resin, comprising the steps of: A), providing a cresol novolak epoxy resin; the part of the cresol novolac epoxy resin and 9,10-dihydro - 9-oxa-10-phosphaphenanthrene phenanthrene-10-oxide is heated at a temperature of melt-mixing 170 ℃ to 200 ℃, and ring-opening addition reaction in the presence of 60ppm to 80ppm boron trifluoride ethylamine, the reaction to an epoxy value of 2.8 equivalent / 000 g to 3 equivalents / 000 g; B), the above intermediate was reduced at 90 ℃ to 60 ℃, and the solvent is added to the cooling process, comprising forming an epoxy value of 2.65 eq / 000 g to 2.95 eq / 000 g of the intermediate product mixture and a solvent; C), and another portion of the solvent to dissolve the cresol novolac epoxy resin was added to the mixture, to obtain a phosphorus-containing phenol ring a epoxy resin. The method of the present invention is a novel process rational, simple, easy to operate, good product quality.