MAGNETIC RECORDING MEDIUM

摘要

PURPOSE:To obtain excellent wear resistance by providing a back coating layer contg. a carbon black graft polymer obtd. by ringing a carbon black and a polymer having reactivity with the carbon black into reaction under the conditions of an ordinary temp.-350 deg.C to a titled medium. CONSTITUTION:The carbon black graft polymer (CB graft polymer) obtd. by bringing the polymer having the reactivity with the carbon black (CB) into reaction with the CB under the specific conditions is used. Namely, the back coating layer contg. the CB graft polymer obtd. by bringing the CB and the polymer having the reactivity with the CB into reaction under the conditions of the ordinary temp.-350 deg.C is used. The CB is uniformly microdispersed into the back coating layer where the CB and the binder component adhere tightly to each other and, therefore, the back coating layer is extremely rigid and the dislodgment of the CB is obviated. The excellent wear resistance is thereby obtd.