MAGNETIC RECORDING MEDIUM

摘要

PURPOSE:To improve corrosion resistance and durability and to improve writing and reading efficiency as well by forming an optomagnetic recording layer provided with a mixed film composed of oxide and nitride of Si, etc. on one or both sides of an amorphous magnetic material on a plastic substrate. CONSTITUTION:A mixed film 2 composed of oxide and nitride such as Si3N4 and SiO2 or SiO; AlN and Al2O3 is formed as an undercoating layer on a transparent plastic substrate 1a to be used on a writing side. The oxide and nitride are formed to a desired ratio according to the ratio of N2 and O2 in the atmosphere in the stage of vapor deposition so that the layer 2 having a desired refractive index is obtd. A recording layer 3 for an optothermomagnetic recording medium such as GdTbFe or the like and an optomagnetic recording medium such as MnNi or the like is then formed on the layer 2. A mixed oxide and nitride layer is formed as a spacer layer 4 on the layer 3 in the same way as for the layer 2. A reflecting layer 5 such as an Al film is formed on the layer 4 and thereafter an outside substrate 1b consisting of plastic is provided via an adhesive layer 6. The durability of the recording layer 3 is thus improved and the improvement in writing and reading efficiency is made possible by adjusting the refractive indices of the layers 2, 4.