FIELD: production of epoxy resins and adhesives. SUBSTANCE: method involves condensation of phenol and formaldehyde at their ratio about stoichiometric one. The process takes place with the help of sulfuric acid, desired product is isolated by recrystallization of organic residue of vacuum distillation of reaction mass. Said recrystallization takes place of acetic acid. Phenol-formaldehyde mixture is added by portions, its quantity is so that it provides dissolution in 10-50 % acid, each next portion being added when reaction in former portion is completed and when thus prepared product as phenol extract is removed of reaction zone. Said extraction takes place with the help of recurrent phenol, its quantity being 5-20 % of mass of acid. Formalin, paraform or trioxane are used as source of formaldehyde. EFFECT: improves efficiency of the method. 5 cl
