| 摘要 |
PURPOSE:To obtain a thin ferromagnetic metallic film type magnetic recording medium having superior wear resistance and durability by forming a thin ferromagnetic metallic film on a nonmagnetic support and sticking an extreme pressure agent contg. sulfur and org. metallic compound type extreme pressure agent to the metallic film so as to maintain the lubricity for a long period and to reduce the coefft. of friction. CONSTITUTION:An extreme pressure agent reacts with a metallic surface by frictional heat when the agent is brought into partial contact with the metal in a boundary lubricating region, and the agent performs friction and wear preventing actions by a formed reaction product film. Extreme pressure agents contg. sulfur include sulfurized fats and oils such as sulfurized sperm oil, disulfides such as dibenzyl disulfide, monosulfides such as dibenzyl sulfide and polysulfides such as dimethyl trisulfide. Org. metallic compound type extreme pressure agents include thiophosphates such as zine diisobutyldithiophosphate and thiocarbamates such as zinc dimethyl dithiocarbamate and other metallic dialkyldithiocarbamates. An extreme pressure agent contg. sulfur and an org. metallic compound type extreme pressure agent are added to a lubricant acting usually as an oily agent and stuck to a thin ferromagnetic metallic film to form a protective layer. |
