Abstract: To produce an optical recording medium having a good concavo-convex shape whereby optical information recording/retrieving is stabilized. A process for producing an optical recording medium 100 provided with an interlayer 104 having a concavo-convex shape, which comprises a step of forming a recording layer 102 on a substrate 101 directly or via another layer; a step of placing a resin material layer 104a and a stamper 110 having a concavo-convex shape for transfer, in this order on the recording layer 102, and curing the resin material layer 104a in this laminated state to obtain a bonded body 112 comprising the substrate 101, the recording layer 102, the resin material layer 104a and the stamper 110, and a step of separating the stamper 110 from the resin material layer 104a so that the concavo-convex shape for transfer is transferred to the resin material layer 104a, and applying surface modification treatment to promote the curing of the resin material layer 104a, to form the interlayer 104.

Abstract: To produce an optical recording medium having a good concavo-convex shape whereby optical information recording/retrieving is stabilized. A process for producing an optical recording medium 100 provided with an interlayer 104 having a concavo-convex shape, which comprises a step of forming a recording layer 102 on a substrate 101 directly or via another layer; a step of placing a resin material layer 104a and a stamper 110 having a concavo-convex shape for transfer, in this order on the recording layer 102, and curing the resin material layer 104a in this laminated state to obtain a bonded body 112 comprising the substrate 101, the recording layer 102, the resin material layer 104a and the stamper 110, and a step of separating the stamper 110 from the resin material layer 104a so that the concavo-convex shape for transfer is transferred to the resin material layer 104a, and applying surface modification treatment to promote the curing of the resin material layer 104a, to form the interlayer 104.

Abstract: A magneto-optical recording medium having a writing layer, a switching layer and a readout layer on a substrate, wherein a magnetization direction corresponding to information is written in the writing layer, and the magnetization direction of the writing layer is transferred to the readout layer by a magnet static coupling force from the writing layer at a temperature of at least room temperature, and wherein the writing layer is composed of a plurality of layers which are made of alloys of a rare earth metal and a transition metal and which are exchange-coupled one another, including a layer having rare earth metal dominant magnetization at room temperature and a layer having transition metal dominant magnetization at room temperature.

Abstract: An information recording medium comprising a substrate provided with recessed pits or grooves, and at least a metal layer and a light transmitting layer formed on the substrate in this order, or a metal substrate provided with recessed pits or grooves, and a light transmitting layer formed on the metal substrate, so that a light is applied from the light transmitting layer side to readout information from the pits or grooves, wherein the minimum width W of the pits or grooves and the wavelength .lambda. in air of the readout light satisfy:W/.lambda..ltoreq.0.6 (1)and the refractive index n of the light transmitting layer, the thickness Tf of the light transmitting layer and the maximum depth d of the pits or grooves satisfy:n.gtoreq.1.6 (2)1.2d/n<Tf<.lambda.

Abstract: A magneto-optical recording medium having a writing layer formed on a transparent substrate provided with a groove having a flat bottom surface and a flat land, so that writing or readout is carried out on either the groove or the land only by irradiating a laser beam from the substrate side, wherein the sum (.alpha.+.beta.) of a phase shift .alpha. of a reflected light of a readout beam by the substrate and a phase shift .beta. thereof by a layer structure on the transparent substrate, is made to have an opposite sign to a phase shift .gamma. by interference of reflected lights from the groove and the land.

Abstract: A magneto-optical recording medium having a land/groove track formed on a transparent substrate, wherein the land and the groove of the land/groove track each has a substantially flat region, and recording is made on both the land and the groove, wherein at least an interference layer made of a dielectric and a magnetic layer made of a magnetic amorphous alloy of rare-earth metal and transition metal and having a thickness of at least 50 nm are formed, in this order, on the substrate, and relationships represented by the following formulas are satisfied:0.5.ltoreq.N-Nsub.ltoreq.1.00.5.ltoreq.d.times.(N.sup.2 /.lambda.)d.times.N/.lambda..ltoreq.0.32wherein Nsub is the refractive index of the substrate, N is the refractive index of the interference layer, d is the thickness (nm) of the interference layer, and .lambda. is the wavelength (nm) in air of a readout beam.

Abstract: The disclosure describes a magneto-optical recording medium comprising a substrate and a magnetic layer comprising at least a readout layer, a cut-off layer and a memory layer disposed on said substrate in order,said magnetic layer having the properties that when said magnetic layer is heated by irradiation of readout beams for readout of information, a sub-lattice magnetization direction of at least the layer concerned with readout in said magnetic layer at the high-temperature region is reversed relative to the magnetization direction at the low temperature of said region, andwhen the temperature of the magnetic layer lowers after passage of the readout beams, the sub-lattice magnetization direction is restored; and a recording and readout method of the magneto-optical recording medium.

Abstract: A magneto optical recording medium comprising the following elements has been developed:a substrate;an interference layer of tantalum oxide having 500 to 1,200 .ANG. in thickness and formed on said substrate;a recording layer formed on said interference layer;a heat insulating layer of silicon nitride, silicon oxide or a mixture thereof having 200 to 500 .ANG. in thickness and formed on said recording layer; anda reflective layer of Al or an Al-based alloy having 400 to 1,200 .ANG. in thickness and formed on said heat insulating layer.

Abstract: Disclosed herein is a read-only optical disk comprising an annulus transparent substrate of a synthetic resin having information pits thereon, a reflective layer comprising an Al alloy containing Ta and a protective layer provided thereover. The read-only optical disk according to the present invention is excellent in the corrosion resistance and has a high reliability.

Abstract: A magneto-optical recording medium capable of overwriting which comprises a substrate, a magneto-optical recording layer provided on the substrate, a recording auxiliary layer provided on the substrate, a recording auxiliary layer provided on the magneto-optical recording layer and a heat sink layer provided on the side of the recording auxiliary layer.