Halogen-free flameproof epoxy resin formulations

摘要

The invention relates to a method for preparing halogen-free flameproof epoxy resins, in which a halogen-free epoxy resin is reacted with a polyfunctional aldehyde or ketone and a phosphinic acid derivative, wherein the phosphinic acid derivative contains at least one P—H-active structural unit of the formula ═PH(O) and is used in an amount equivalent to the polyfunctionality of the aldehyde or ketone, to a halogen-free flameproof epoxy resin obtainable by this method, to the use of the epoxy resin as a base material for the manufacture of printed circuit boards and printed circuits and to intermediates used to prepare the epoxy resins.