| 摘要 |
PURPOSE:To lower friction coefft. and to enhance durability, by using a magnetic coating film contg. as binder components a specified polyurethane resin and an acrylonitrile-butadiene copolymer in a specified proportion, and moreover, polyisocyanate in addition. CONSTITUTION:The binder components of the magnetic coating film contains a polyurethane resin having <=170kg/cm<2> 100% modulus and an acrylonitrile- butadiene copolymer in 90:10-60:40 ratio, and moreover, polyisocyanate for accelerating cross-linking reaction in 20-80pts. per 100pgs. of the binder. The use of such binder components enhances strength of the coating film greatly, and enhances durability. When polyisocyanate is added by <=20pts., the mechanical strength of the coating film is lowered, and when by >=80pts., it becomes brittle, so both cases are not preferable. |
