Abstract: A light reflecting and heat dissipating material which is capable of reflecting light and dissipating heat transmitted thereto from a layer in contact with or adjacent to the material to cool the layer is composed of an alloy represented by formula (I):Ag.sub.x Pd.sub.1-x (I)wherein 0.6.ltoreq..times..ltoreq.0.85. An optical information recording medium for recording information, reproducing and erasing recorded information is composed of a substrate, a recording layer formed thereon and a light reflection and heat dissipation layer composed of the above light reflecting and heat dissipating material formed on the recording layer.

Abstract: A phase-change type information recording medium composed of a substrate and a recording layer formed on the substrate, which recording layer is composed of a recording material with the composition thereof in terms of atomic percentage being represented by general formula:Ag.sub..alpha. In.sub..beta. Te.sub..gamma. Sb.sub..delta. +M.sub.x0.5.ltoreq.x.ltoreq.10, .alpha.+.beta.+.gamma.+.delta.+x=100, and M is onewherein 5.ltoreq..alpha..ltoreq.17, 6.ltoreq..beta..ltoreq.18, 13.ltoreq..gamma..ltoreq.36, 33.ltoreq..delta..ltoreq.77, additional element selected from the group consisting of B, N, C, P and Si.

Abstract: An information recording medium is disclosed which records information through the transition of two phases of a recording material, utilizing electromagnetic wave energy. The information recording medium comprises a recording layer made up of a recording material of a composition represented by the formula:wherein6.ltoreq..alpha..ltoreq.138.ltoreq..beta..ltoreq.1718.ltoreq..gamma..ltoreq.2845.ltoreq..delta..ltoreq.66.alpha.+.beta.+.gamma.+.delta.=100.

Abstract: An information recording medium comprising a substrate, and a recording layer formed thereon, which comprises as the main component a compound having the following formula:(X.sub.a Y.sub.b Z.sub.c).sub.1-d O.sub.dwherein X is an element selected from the group consisting of the elements belonging to the Ib group and IVb group in the periodic table, Y is an element selected from the group consisting of the elements belonging to the Vb group in the periodic table, Z is an element selected from the group consisting of the elements belonging to the VIb group in the periodic table, and a, b, c, and d fulfill the following conditions:0.05.ltoreq.a.ltoreq.0.35,0.10.ltoreq.b.ltoreq.0.40,0.40.ltoreq.c.ltoreq.0.60,a+b+c=1, and0.05.ltoreq.d.ltoreq.0.20.

Abstract: An optical information recording medium is composed of a substrate and a recording layer, formed thereon, which recording layer causes the reversible phase change by the application of an electromagnetic wave thereto, and comprises a phase-changeable type alloy with the composition of (XYZ.sub.2).sub.1-x M.sub.x, wherein X is an element of the group Ib, Y is an element of the group Va, Z is an element of the group VIa, M is an element selected from the group consisting of Sb, Bi, In, Al and Ga, and 0<x<1.

Abstract: An information recording medium comprises a substrate and a recording film layer thereon comprising a hydrocarbon polymer and finely-divided particles of a metallic component dispersed therein, which recording film layer is a plasma polymerized film prepared by subjecting an organic metallic complex containing a center metal to glow discharging decomposition. The metallic component in the recording film layer may be a metal, a metal oxide or a composition of a metal and a metallic oxide.

Abstract: An information recording medium comprising a substrate, and a recording layer formed thereon which comprises (a) a carbon-based material and (b) an optically reversible material whose optical characteristics can be reversibly changed, with the thermal decomposition temperature of the carbon-based material being higher than the melting point of the optically reversible material.

Abstract: A phase-change type optical information recording medium is disclosed, which medium comprises a substrate and a recording layer formed thereon. The recording layer comprises a phase-transition type compound consisting of 4 to 6 elements, having a chalcopyrite structure, represented by the following formula (I):X.multidot.Y.multidot.Z.sub.2 (I)wherein X represents one or two elements selected from the group consisting of elements belonging to the groups Ib and IIb in a periodic table; Y represents one or two elements selected from the group consisting of elements belonging to the groups IIIb, IVb and Vb in the periodic table; and Z represents one or two elements selected from the group consisting of elements belonging to the groups Vb and VIb in the periodic table.

Abstract: A masking layer is formed on the light-emitting mirror surface of a semiconductor laser body. The masking layer is capable of blocking or cutting off light emitted from the semiconductor laser body and of being made optically transparent by exposure to the light emitted from the semiconductor laser body dependent on the amount of energy of the emitted light. When the light is emitted from the semiconductor laser body on which the masking layer is deposited, a small light-emitting hole is defined in the masking layer, the light-emitting hole having a desired diameter commensurate with the amount of energy of the emitted light which is applied to the masking layer.

Abstract: A layered electrophotographic photoconductor comprising an electrically conductive base; a charge transporting layer, formed on the electrically conductive base, which charge transporting layer comprises a selenium-tellurium alloy, doped with halogen; and a charge generating layer, formed on the charge transporting layer, which charge generating layer comprises a selenium-tellurium-arsenic alloy, doped with halogen.