| 摘要 |
PURPOSE:To enable the production of a titled medium having <=4% (Io-I)/Io, by forming a magnetic layer consisting of Co and Cr on a substrate consisting of a polymer material by vacuum deposition under the optimum conditions for the coefft. of linear expansion of the substrate and the temp. in the stage of vapor deposition. CONSTITUTION:A Co-Cr vertically magnetized film contg. 20wt% Cr and having the axis of easy magnetization in the perpendicular direction of the film is formed with a vacuum deposition device shown in the figure. A film of 12mu thickness consisting of a heat resistant polymer material of polyamide type is used as a substrate 1, and the film is formed on the substrate 1 through a mask 8 at 230 deg.C temp. on the circumferential side surface of a can 2 to 2,000Angstrom thickness of the Co-Cr film at 10m/min traveling speed of the substrate 1. The coefft. of thermal expansion of the film is 1.6X10<-5>/ deg.C, and the resultant magnetic recording medium is positively curled and has 2% (Io-I)/Io. |
