PURPOSE: To prevent the deterioration of a memory medium by using an allay containing at least one kind selected from among specified metals and at least one kind of metal selected from among the groups Va, VIa, VIIa and Ib in the periodical table for the memory medium.
CONSTITUTION: The specified metals for the alloy of the medium are ruthenium, rhodium, palladium, osmium, iridium and platinum. Metals in the groups Va, VIa, VIIa, and Ib in the Mendeleev's periodical table are V, Nb, Ta; Cr, Mo, W; Mn, Tc, Re; and Cu, Ag, and Au. Technetium Tc can not be used because of its radioactivity. The alloy may contain one or more kinds of iron, cobalt and nickel. By this method, even when the medium is repeatedly used for reading for a long time with rather high laser output, decrease in the output can be prevented.
PIITAA ROI HERUFUETSUTO
MAIKERU JIYON EIBURAMUZU
| JPS62156585U | 1987-10-05 | |||
| JPS4890092U | 1973-10-30 | |||
| JPS5721389Y2 | 1982-05-10 |