Abstract: A magnetic recording medium comprising a substrate, a ferromagnetic thin film formed on the substrate, and a protective film formed directly on the ferromagnetic think film, and a process for producing such magnetic recording medium. The expression "formed directly" refers to the technique for forming the protective film on the ferromagnetic thin film so that the interface therebetween is free from contamination by, for instance, conducting the protective film formation under the vacuum used when forming the ferromagnetic thin film.

Abstract: A non-magnetic substrate used for a magnetic head comprising a pair of non-magnetic substrates, and a magnetic layer structure sandwiched between the pair of non-magnetic substrates. The magnetic layer structure is comprised, of alternately laminated magnetic layers and intermediate insulating layers. The invention discloses for the substrate material a composition expressed by Zn.sub.x M.sub.y Co.sub.2-x-y O.sub.2, with the proviso that M is Mn or Ni, 0.ltoreq.x.ltoreq.0.4, 0.4.ltoreq.y.ltoreq.1.0, 0.8.ltoreq.x+y.ltoreq.1.0, or CO.sub.x Ni.sub.2-x O.sub.2, with the proviso that 0.2.ltoreq.x.ltoreq.1.8, and having a rock-salt structure.

Abstract: A magneto-optical recording element comprises(A) an optically transparent dimensionally stable substrate and(B) a thermally alterable recording layer which contains an amorphous lanthanide/transition metal alloy and, at least on the side facing away from the substrate (A), has a 0.1-20 nm thick surface zone containing one or more of the substances carbon, oxygen and nitrogen.

Abstract: In a sheet-like, multilayer, magneto-optical recording material which has a base which is transparent to light, a thermally alterable recording layer of an amorphous lanthanide transition metal alloy and, on the base remote side of this recording layer, an anticorrosion layer containing carbides, nitrides and/or oxides, the anticorrosion layer(a) is from 30 to 250 nm thick and(b) consists of two or more components which(c) are present in four or more separate strata, each consisting of one of the components,(d) one or more of the components being selected from the group consisting of the elements boron, aluminum, silicon, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum and tungsten and(e) one or more of the other components being selected from the group consisting of the carbides, nitrides and oxides of these elements (d) and(f) directly adjacent strata always consisting of components which differ from one another.

Abstract: In constructoin of a magnetic recording medium provided with one circular track for magnetic graduations and another circular track for standard marks, the standard marks are accompanied with specified magnetic identification marks so that discrimination between the standard marks can be fairly done without any influence by the number of the standard marks only by reading them out together with the identification marks. The medium is advantageously used for displacement detectors such as magnetic rotary encoders and magnetic linear scales.

Abstract: An information recording element consists of one or two substrates, on each of which a magnetooptical recording layer enclosed on both sides by dielectric layers is applied. The composite consisting of substrate - dielectric layer-recording layer-dielectric layer is adhesively bonded to a further substrate or to a plastic layer by means of a flexible adhesive foam layer applied over the entire surface. In the case of adhesive bonding over the entire surface, air gaps are excluded. The thermal stability of the adhesive foam layer ranges from about -40.degree. C. to +150.degree. C. and the adhesive foam layer is resistant to solvents and plasticizers. The heat penetration coefficient of the adhesive foam layer is lower than the heat penetration coefficient of quick-curing adhesives and of polyurethane adhesives which cure by moisture absorption, and is less than about 450 W.s.sup.1/2 /K.m.sup.2.

Abstract: An information storage medium comprises a substrate, and a magnetic optical recording layer provided on the substrate. A surface portion of the recording layer has a hydrogen-doped portion having a higher hydrogen concentration than that of the other portions of the recording layer. Thus, the recording layer has two portions which have different coercive forces, though being of the same composition. The recording layer is immersed in an aqueous solution having a pH of 4 to 10, to cause hydrogenation reactions to take place on the surface of the recording layer. Another information storage medium comprises a substrate, a magneto-optical recording layer deposited on the substrate, containing a rare earth-transition metal amorphous alloy, and a protective layer deposited on the recording layer. A hydrogenated area is formed by doping hydrogen atoms in the surface portion of the recording layer before the protective layer is formed.

Abstract: A high-density information recording carrier such as an optical disk which is used for recording and/or playing back information carried on a plastic substrate by means of laser beams has an improved protective layer between a recording layer and the plastic substrate. The protective layer is made of inorganic glass made of alkali-free glass containing less than 1 wt % of alkali metal oxides. The resulting optical disk shows improved durability, higher C/N, lower BER and higher film forming rate.

Abstract: There is disclosed an optical recording medium provided with an optical recording layer on a substrate, in which a layer of nitride of a substance selected from tungsten, zirconium, titanium, niobium, vanadium, tantalum and chromium is formed on a side or both sides of the optical recording layer.

Abstract: An anti-corrosion ferromagnetic film and a magnetic head using the crystalline ferromagnetic film are disclosed. The anti-corrosion film contains an element interstitially soluble to iron, in addition to iron used as the main component, and further contains at least one element selected from the group consisting of Ni, Rh, Ru, Pd, Zr, Nb, Ta, Ag, Os, Ir, Pt, Au, Cr, Mo, W, Ti, Bi, V, Co and Cu, at a concentration value of 0.5 to 5 atomic percent.