Magnetic recording binder containing aminoalkylphosphonate salt.

摘要

A magnetic recording medium is prepared by applying a magnetic coating composition onto a non-magnetic support and curing said composition, said coating composition containing ferromagnetic particles dispersed in a binder comprising a thermoplastic polyurethane or polyester resin wherein there is chemically bonded to said resin at least one aminoalkylphosphonate represented by the formula: wherein R<1> and R<2> are the same or different oxyalkyl radicals having from 2 to 12 carbon atoms, R<3> is an alkyl radical having from 1 to 12 carbon atoms, or an aralkyl radical having from 7 to 10 carbon atoms R<4> is an alkyl radical having from 1 to 12 carbon atoms, a cycloalkyl radical having from 5 to 12 carbon atoms, or an aryl radical having from 6 to 12 carbon atoms wherein the aryl radical may contain a halogen atom, a hydroxyl group, or an amino group, and M<+> is a metal ion or an ammonium ion.