Magnetic recording media.

摘要

In magnetic recording media consisting of a nonmagnetic substrate and one or more magnetizable layers bonded thereon and based on a polyurethane binder, the binder consists of not less than 50% by weight of an isocyanate-free, branched polyurethane which is soluble in tetrahydrofuran and has sulfonate groups along the polyurethane branches and OH-containing urea groups at the chain ends and a molecular weight of from 4,000 to 30,000.