| 摘要 |
PURPOSE:To obtain excellent durability and environmental adaptability by incorporating or holding a specified urea deriv. into a magnetic layer. CONSTITUTION:The magnetic layer provided on a nonmagnetic base contains or holds the urea deriv. expressed by formula I. In the formula I, R1 denotes>=10 and <=26C hydrocarbon group; R2, R4 denote hydrogen or >=1 and <=26C hydrocarbon groups which are the same or different; R3 denotes >=1 and <=26C hydrocarbon group. Further preferably, the magnetic layer contains ferromagnetic powder and binder. |
