Abstract: An information recording medium including three or more information layers, wherein: at least one information layer includes a recording layer and a nucleation layer; the recording layer contains a material that is represented by formula (1) [(Ge0.5Te0.5)x(In0.4Te0.6)1-x]ySb100-y (mol %) with x satisfying 0.8?x<1.0 and y satisfying 95?y<100; the nucleation layer contains a material that is represented by formula (2) (Ge0.5Te0.5)z(Bi0.4Te0.6)100-z (mol %) with z satisfying 10?z?71; and the nucleation layer is in contact with the recording layer. This information recording medium is capable of achieving sufficient signal amplitude even in cases where a small recording mark is formed, and is also capable of stably maintaining a small recording mark.

Abstract: An information recording medium (1) of the present invention is an information recording medium allowing information to be recorded thereon by irradiation with a laser beam or by application of electrical energy. The information recording medium (1) includes a recording layer (15) capable of undergoing a phase change by the irradiation with the laser beam or by the application of the electrical energy. The recording layer (15) contains Sb, Te, Ge, and C, and a content of Te in the recording layer (15) is at least 8 atom % but not more than 25 atom %.

Abstract: An optical information recording medium (9) of the present invention is an optical information recording medium including: N information layers, where N is a natural number of 2 or more; and an intermediate layer for separating the N information layers optically from each other. With the N information layers being referred to as a first information layer (10) to an N-th information layer (7) sequentially from an optical beam incident side, a first information layer (10) corresponding to an L-th information layer included in the N information layers includes a recording layer (104) on which information can be recorded by irradiation with an optical beam, a reflective layer (108), and a transmittance adjusting layer (109) in this order from the optical beam incident side, where L is an at least one natural number that satisfies 1?L?N?1. The transmittance adjusting layer (109) contains tungsten (W) and oxygen (O).

Abstract: An information recording medium of the present invention includes a recording layer whose phase changes by irradiation with a laser beam or application of current. The recording layer contains, as its main component, a composite composed of Ge and Sb that are essential components, and Te that is an optional component. The composite has a composition within a region enclosed by: point (a) (35, 65, 0), point (b) (36.9, 60, 3.1), point (c) (3.2, 60, 36.8), and point (d) (5, 95, 0) in terms of a coordinate (Ge, Sb, Te)=(x, y, z) on the triangular coordinate shown in FIG. 1, where point (b) corresponds to a point at Sb=60 on Ge60Te40—Ge35Sb65, point (c) corresponds to a point at Sb=60 on Te—Ge5Sb95, and the region includes lines extending between point (a) and point (b), point (b) and point (c), point (c) and point (d), and point (d) and point (a).

Abstract: An optical information recording medium having the same recording volume as that of DVD-ROM is obtained which shows excellent characteristics at recording linear velocities within a range of twice linear velocity of DVD (about 8.2 m/s) to five times liner velocity of DVD (about 20.5 m/s) and excellent archival stability, by a construction including a transparent substrate, a recording layer which is formed on the substrate directly or with another layer interposed therebetween and can change in phase reversibly by a laser beam irradiation, wherein the composition of the recording layer is within a region bounded by composition points A(41.2, 7.4, 51.4), B(39.8, 10.5, 49.7), C(28.5, 21.7, 9.8), and D(30.6, 15.8, 53.6) in a triangular coordinate graph represented with a coordinate of (Ge, Sb—Bi, Te) and a Bi content in the recording layer is 4 atom % and more and less than 13 atom %.

Abstract: An optical information recording medium (100) of the present invention includes an information layer (011) that allows information to be recorded thereon and reproduced therefrom by irradiation with a laser beam (040). The information layer (011) includes a reflective layer (002), a first dielectric layer (003), a recording layer (005) capable of undergoing a phase change by the irradiation with the laser beam (040) and a second dielectric layer (007) formed in this order from a side opposite to a laser beam incident side. The recording layer (005) contains Ge, Sb and Te. When Ge, Sb and Te contained in the recording layer (005) are represented by GexSbyTez in atomic number ratio, x, y, and z satisfy 0.39?x?0.48, 0.02?y<0.11, 0.40?z<0.56, and x+y+z=1. The recording layer (005) has a thickness of at least 10 nm but not more than 15 nm.

Abstract: An information recording medium (1) of the present invention is an information recording medium allowing information to be recorded thereon by irradiation with a laser beam or by application of electrical energy. The information recording medium (1) includes a recording layer (15) capable of undergoing a phase change by the irradiation with the laser beam or by the application of the electrical energy. The recording layer (15) contains Sb, Te, Ge, and C, and a content of Te in the recording layer (15) is at least 8 atom % but not more than 25 atom %.

Abstract: An optical information recording medium (9) of the present invention is an optical information recording medium including: N information layers, where N is a natural number of 2 or more; and an intermediate layer for separating the N information layers optically from each other. With the N information layers being referred to as a first information layer (10) to an N-th information layer (7) sequentially from an optical beam incident side, a first information layer (10) corresponding to an L-th information layer included in the N information layers includes a recording layer (104) on which information can be recorded by irradiation with an optical beam, a reflective layer (108), and a transmittance adjusting layer (109) in this order from the optical beam incident side, where L is an at least one natural number that satisfies 1?L?N?1. The transmittance adjusting layer (109) contains tungsten (W) and oxygen (O).

Abstract: An optical information recording medium of the present invention includes at least a recording layer (4) that allows information to be recorded thereon and/or reproduced therefrom by being irradiated with a laser beam, and a transmittance adjusting layer (7) in this order from an incident side of the laser beam (30). In the optical information recording medium of the present invention, the transmittance adjusting layer (7) contains Bi, Ti, and O and with a composition of Bi, Ti, and O contained in the transmittance adjusting layer (7) being denoted as BixTiyOz, in atomic number ratio, x, y, and z satisfy 0.07?x?0.35, 0.07?y?0.28, 0.56?z?0.70, and x+y+z=1. Or the transmittance adjusting layer (7) contains Bi2O3 and TiO2, and with a composition of Bi2O3 and TiO2 contained in the transmittance adjusting layer (7) being denoted as (Bi2O3)?(TiO2)?, in molar ratio, ? and ? satisfy 0.2???0.7, 0.3???0.

Abstract: The optical information recording medium of the present invention includes a plurality of information layers provided on a substrate and an optical separating layer provided between information layer adjacent to each other, and information is recorded or reproduced by irradiation of a laser beam. When an information layer that is provided closest to a laser beam incident side of the plurality of information layers is taken as a first information layer and an optical separating layer provided in contact with the first information layer is taken as a first optical separating layer, then the first information layer comprises a recording layer, a transmittance adjusting layer that adjusts a transmittance of the first information layer, and a low refractive index layer provided between the transmittance adjusting layer and the first optical separating layer.

Abstract: An optical information recording medium having the same recording volume as that of DVD-ROM is obtained which shows excellent characteristics at recording linear velocities within a range of twice linear velocity of DVD (about 8.2 m/s) to five times liner velocity of DVD (about 20.5 m/s) and excellent archival stability, by a construction including a transparent substrate, a recording layer which is formed on the substrate directly or with another layer interposed therebetween and can change in phase reversibly by a laser beam irradiation, wherein the composition of the recording layer is within a region bounded by composition points A(41.2, 7.4, 51.4), B(39.8, 10.5, 49.7), C(28.5, 21.7, 9.8), and D(30.6, 15.8, 53.6) in a triangular coordinate graph represented with a coordinate of (Ge, Sb—Bi, Te) and a Bi content in the recording layer is 4 atom % and more and less than 13 atom %.

Abstract: It is an object to provide an optical information recording medium for land/groove recording, capable of recording at a plurality of linear speeds, wherein deterioration of jitter of the reproduction signal is prevented in recording and reproduction at low linear speeds. To this end, there is provided an optical information recording medium having a land/groove structure and being capable of recording at a plurality of linear speeds, wherein the ratio of the maximum recordable linear speed to the minimum recordable linear speed has a value of 2 to 3, and the ratio of the amount of light reflected from a groove in an unrecorded state to the amount of light reflected from a land in an unrecorded state has a value of at least 1.08 and no more than 1.19.

Abstract: An information recording medium of the present invention includes a recording layer whose phase changes by irradiation with a laser beam or application of current. The recording layer contains, as its main component, a composite composed of Ge and Sb that are essential components, and Te that is an optional component. The composite has a composition within a region enclosed by: point (a) (35, 65, 0), point (b) (36.9, 60, 3.1), point (c) (3.2, 60, 36.8), and point (d) (5, 95, 0) in terms of a coordinate (Ge, Sb, Te)=(x, y, z) on the triangular coordinate shown in FIG. 1, where point (b) corresponds to a point at Sb=60 on Ge60Te40—Ge35Sb65, point (c) corresponds to a point at Sb=60 on Te—Ge5Sb95, and the region includes lines extending between point (a) and point (b), point (b) and point (c), point (c) and point (d), and point (d) and point (a).

Abstract: An optical information recording medium includes one or more information layers including a recording layer for recording/reproducing an information signal by irradiation with a laser light, and a seperating layer or a protective substate on which a first information layer of the information layer on the irradiation face side is formed. The seperating layer or the protective substrate having a guide groove spirally or concentrically formed on the surface, and the respective inclined planes on the inner perimeter side and the outer perimeter side of the guide groove having inclined angles ? and ? with respect to the bottom face of the guide groove. The guide groove has one or more dissymmetric regions in the radius direction where the inclined angles ? and ? are different. The information layer has roughly agreeing thicknesses in the inclined face portion on the inner and outer perimeter sides in the dissymmetric region.

Abstract: An optical information recording medium with favorable recording/reproducing characteristics and corrosion resistance is offered. To this end, the optical information recording medium of the present invention comprises in this sequence at least substrate 001 that has a guide groove, reflective layer 002, light-absorbing layer 003, reflected light side protective layer 004, recording layer 006 with optical properties that are transformed reversibly due to irradiation with laser light, incident light side protective layer 012 with a film thickness ?50 nm, resin layer 010, and a transparent substrate 011 that is irradiated with laser light, where incident light side protective layer 012 includes a plurality of material layers, and among this plurality of material layers, a layer that constitutes an incident light side material layer 009 which is the most closest to the transparent substrate has minimum internal stress.

Abstract: The present invention provides an optical information recording medium of excellent signal quality in high density recording onto a semitransparent information layer, its manufacturing method and a manufacturing apparatus. The optical information recording medium of the present invention includes at least a semitransparent information layer disposed between a circular transparent substrate and a protective substrate, in which the information layer has spiral grooves for guiding a light beam, and also includes a recording film capable of recording/reproducing information thereon/therefrom by changing at least in two states detectable optically by irradiation of the light beam from the transparent substrate side, and the difference in film thickness of slope portions of the inner circumferential side and outer circumferential side of the groove is within ±10% in the entire region for recording/reproducing information.

Abstract: An optical information recording medium comprises at least a substrate with a guide groove, a reflective layer, a recording layer whose optical characteristics change reversibly under irradiation with a laser beam, a protective layer, a resin layer, and a transparent substrate, in that order, wherein the protective layer and the resin layer are in contact, and the protective layer is composed of an oxide of zinc an main component.

Abstract: It is an object to provide an optical information recording medium for land/groove recording, capable of recording at a plurality of linear speeds, wherein deterioration of jitter of the reproduction signal is prevented in recording and reproduction at low linear speeds. To this end, there is provided an optical information recording medium having a land/groove structure and being capable of recording at a plurality of linear speeds, wherein the ratio (SH/SL) of the maximum recordable linear speed (SH) to the minimum recordable linear speed (SL) has a value of 2 to 3, and the ratio (RG/RL) of the amount of light reflected from a groove (RG) in an unrecorded state to the amount of light reflected from a land (RL) in an unrecorded state has a value of at least 1.08 and no more than 1.19.

Abstract: An optical information recording medium is provided which has favorable signal quality even in high density recording using a translucent information layer. The optical information recording medium includes one or more information layers including a recording layer for recording/reproducing an information signal by irradiation with a laser light, and a separating layer or a protective substrate on which a first information layer of the information layer on the irradiation face side is formed, the separating layer or the protective substrate having a guide groove spirally or concentrically formed on the surface, and the respective inclined planes on the inner perimeter side and the outer perimeter side of the guide groove having inclined angles ? and ? with respect to the bottom face of the guide groove. The guide groove has one or more dissymmetric regions in the radius direction where the inclined angles ? and ? are different.

Abstract: The optical information recording medium of the present invention includes a plurality of information layers provided on a substrate and an optical separating layer provided between information layer adjacent to each other, and information is recorded or reproduced by irradiation of a laser beam. When an information layer that is provided closest to a laser beam incident side of the plurality of information layers is taken as a first information layer and an optical separating layer provided in contact with the first information layer is taken as a first optical separating layer, then the first information layer comprises a recording layer, a transmittance adjusting layer that adjusts a transmittance of the first information layer, and a low refractive index layer provided between the transmittance adjusting layer and the first optical separating layer.