POLYURETHANE RESIN FOR MAGNETIC RECORDING MEDIUM

摘要

PURPOSE:To provide the titled resin using a specific polyhydroxy compound as a raw material, having excellent mechanical strength and heat-resistance, exhibiting high elastic modulus and moderate flexibility and capable of giving a magnetic recording medium having excellent durability, dispersibility of magnetic powder and smoothness of coated magnetic surface. CONSTITUTION:The objective resin curable with electron beam can be produced by reacting (A) an active-hydrogen-containing polyhydroxyl compound consisting of a polyester polyol produced by adding a saturated aliphatic lactone to dipentaerythritol with (B) a polyisocyanate compound and (C) a compound having active hydrogen and (meth)acryl group. The saturated aliphatic lactone is preferably epsilon-caprolactone and the molar number of added lactone is preferably 2-10mol per 1mol of dipentaerythritol. The component C is preferably 2- hydroxyethyl (meth)acrylate.