| 摘要 |
PURPOSE:To obtain a magnetic recording medium having excellent calendering property and corrosion resistance by using a polyurethane resin obtained by the reaction of a specified high molecular polyol with specified low-mol.wt. polyol and polyisocyanate as the binder of magnetic powder, and forming a magnetic layer using the powder on a carrier. CONSTITUTION:200-2,000 equivalents of a high molecular polyol (A1) contg. polycaprolactone polyol are allowed to react with a low-mol.wt. polyol (A2) shown by the formula [A is the residue of monohydroxymonocarboxylic acid, G is the residue of glycol, (m) and (n) are 0 or >=1, (m+n) is >=1, and the equivalent is <200] and a polyisocyanate to obtain a polyurethane resin (C) which is used as the binder of magnetic powder. The oxypivalic monoester of neopentyl glycol is especiallay used as the polyol (A2) for the resin (C). A magnetic recording medium with excellent dispersibility of magnetic powder and having excellent resistance to scratching and hydrolysis is thus obtained.
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