| 摘要 |
<p>PURPOSE:To obtain a magnetic recording medium having an excellent electromagnetic conversion characteristic as well as excellent running performance and durability by making combination use of a binder consisting essentially of a PVC/ethylene/vinyl acetate/maleic anhydride copolymer and, if necessary, polyisocyanate. CONSTITUTION:The PVC/ethylene/vinyl acetate/maleic anhydride copolymer refers to a copolymer of 50-95wt% PVC, 0.5-20wt% ethylene, 0.5-20wt% vinyl acetate, and 0.5-5wt% maleic anhydride. In the case of a video tape, the recording medium is used under the conditions much severer than for audio tapes; therefore, polyisocyanate is preferably added to the magnetic layer to give higher hardness. The polyisocyanate is exemplified by the reaction product of 3mol diisocyanate such as toluylene diisocyanate, xylene diisocyanate or hexamethylene diisocyanate and 1mol trimethylol propane.</p> |
