| 摘要 |
PURPOSE:To enhance flexibility, surface hardness, etc. by using a quaternary mixture of urethane type and epoxy type acrylic polymers and bifunctional or less functional acrylic oligomer or monomer and a rubber type resin as binders for magnetic particles, and applying electron beam irradiation. CONSTITUTION:A magnetic coating material is prepared by dispersing magnetic particles into a soln. of four kinds of components of polyurethane acrylate; the reaction product of bisphenol A glycidyl ether and acrylic acid; bifunctional or less functional acrylic oligomer or monomer of N-vinylpyrrolidone, 2-ethylhexyl acrylate, diethylene glycol diacrylate, or the like; and a rubber component, such as polybutadiene, and further adding necessary additives, such as lubricant or antistatic agent. A support of a polyester film or the like is coated with said coating material and dried, then irradiated with electron beams and hardened. The magnetic recording medium thus obtd. is strong in adhesion to the support, and superior in surface hardness, retentivity of the magnetic particles, solvent resistance, flexibility, etc. |
