| 摘要 |
<p>PURPOSE:To improve surface properties such as resistance to wear and run operation, by adding a sorbitan-stearate-based surfactant with a sorbitol derivative as a hydrophilic radical to a binder which uses multifunctional aromatic isocyanate as a hardener. CONSTITUTION:To a magnetic coating obtained by dispersing magnetic powder using as a binder synthetic resin (e.g. a copolymer of vinyl chloride and vinyl acetate containing vinyl alcohol) using multifunctional aromatic isocyanate as a hardner, 1-5wt% of a sorbitan-stearate-based surfactant with a sorbitol derivative as a hydrophilic radical such as sorbitan-distearate is added on the basis of the volume of fat. In this way, the surfactant is prevented from reacting upon isocyanate in its early stage to harden resin, and excellent properties can be obtained without deteriorating surface properties (low resistance to wear, run operation, etc.) and strength of a magnetic tape.</p> |
