Sony Corporation

Adeka Corporation

Masatsugu Suwabe

Yutaka Wada

Toru Yano

Koichi Shigeno

Yoshihito Fukushima

Keiji Oya

Yoshihiro Muto

Junko Shimada

Hiroshi Nakayama

Masayoshi Kanno

Toshihiro Akimori

Fuminori Takase

Takahiro Igari

Teruyuki Ota

Yoshihisa Chiba

An optical recording medium includes a plurality of information signal layers, and at least one of the plurality of information signal layers other than the farthest information signal layer from a light irradiation surface includes: a recording layer; a first dielectric layer provided on a side opposite to a light incident side of the recording layer; and a second dielectric layer provided on the light incident side of the recording layer. The first dielectric layer and the second dielectric layer include indium oxide and tin oxide, and the atomic concentration of tin in the first dielectric layer is higher than the atomic concentration of tin in the second dielectric layer.

Optical recording medium

An optical recording medium includes: a substrate having a first principal surface and a second principal surface; one or plural information signal layers formed on the first principal surface of the substrate for undergoing recording or reproduction of information signals upon irradiation with light; and a barrier layer formed on the second principal surface of the substrate for suppressing the gas release from the second principal surface of the substrate, wherein an area of a region exposing from the barrier layer of the second principal surface of the substrate is not more than 688 mm.

Optical recording medium and method for manufacturing the same

Recording and reproducing characteristics and data saving reliability are secured in a write-once two-layer recording medium. A second recording layer from a side irradiated with light for recording and reproduction includes organic dye shown by a general formula of a chemical formula 3 described below (in the formula, R1 and R2 are alkyl groups of carbon number 1 to 4; Y1, Y2 respectively are organic groups independently; and X is Cl0, BF, PF, SbF), and organic dye shown by a general formula of a chemical formula 4 described below (in the formula, R1, R4 are alkyl groups of carbon number 1 to 4; R2, R3 are alkyl groups of carbon number 1 to 4 or groups forming 3 to 6 membered rings by being coupled; Y1, Y2 respectively are organic groups independently; and X is Cl0, BF, PF, SbF), to secure durability. 

Optical recording medium and method of manufacturing the same

Disclosed is to provide with an optical recording medium of a write-once type in which an excellent recording characteristic can be obtained over low speed recording to high speed recording. In an optical recording medium having a recording layer that contains an organic dye, the recording layer is configured to have at least an organic dye expressed by a general formula shown in the following chemical formula 1 (in this formula, R1 represents an alkyl group of carbon number 1 through 4, R2 and R3 represent respectively an alkyl group of carbon number 1 through 4 and a benzyl group or group forming three to six-member ring by coupling, each of Y1 and Y2 represents independently an organic group, and X represents ClO, FB, PF, and SbF) and an organic dye expressed by a general formula shown in the following chemical formula 2 (in this formula, R1 and R4 represent an alkyl group of carbon number 1 through 4, R2 and R3 represent respectively an alkyl group of carbon number 1 through 4 and a benzyl group or group forming three to six-member ring by coupling, each of Y1 and Y2 represents independently an organic group, and X represents ClO, FB, PF, and SbF). 

Optical recording medium and optical recording-reproducing method using thereof

A recording medium is provided and includes; a substrate having a first area formed with a first groove and a second area formed with a second groove, at least one information layer provided on the substrate, and a protecting layer provided on the information layer. Predetermined binary information has previously been recorded on the first groove and the first groove is shallower or narrower than the second groove.

Recording medium, its manufacturing method, mother disc for recording medium, and its manufacturing method

An optical recording medium comprises a transmission substrate and a recording layer formed on the transmission substrate, the recording layer containing at least a dye material expressed by a general formula shown at the following chemical formula (in the chemical formula 1, R1 represents alkyl group having carbon numbers 1 to 4, R2, R3 represent alkyl group having carbon numbers 1 to 4, benzyl group or groups combined to form 3 to 6 rings, Y1 and Y2 independently represent organic groups and X represent ClO, BF, PF, SbF) and a dye material expressed by a general formula represented by the following chemical formula 2(in the chemical formula 2, R1 and R2 represent alkyl groups having carbon numbers 1 to 4, benzyl groups or groups combined to form 3 to 6 rings, Y1, Y2 independently represent organic groups and X represent ClO, BF, PF, SbF):  In a write once type optical recording medium such as DVD&#x2212;R and DVD+R, satisfactory recording characteristics can be obtained from low-speed recording to high-speed recording.

A recording layer records and stores information and comprises a plurality of layers, namely a first layer and a second layer The first layer is made from a recording material which gives parallel directions to saturation magnetization and sublattice magnetization. The second layer is made from a recording material which gives antiparallel directions to saturation magnetization and sublattice magnetization at room temperature. The recording material for the second layer gives parallel directions to saturation magnetization and sublattice magnetization at around a read temperature.

Magneto-optical recording medium

To stably perform optical recording and optical reproducing under optimum conditions, in an optical recording medium having a writable recording layer on a substrate and having a maker recording area in which recording is performed by a maker on the recording layer, individual drive control information of the optical recording medium is recorded in the maker recording area, and, in optical recording and optical reproducing, optical recording and optical reproducing are performed by the drive control information under optimum conditions.

Optical recording medium having individual drive control information recorded in the maker recording area

In a magneto-optical recording medium including a first magnetic layer which is magnetized in a predetermined direction according to a data signal and a second magnetic layer which is magnetically connected to the first magnetic layer by exchange interaction, so that a boundary magnetic wall can exist between the first magnetic layer and the second magnetic layer, the present invention increases stability of the boundary magnetic wall formed between the first magnetic layer and the second magnetic layer and to enhance a reproduction durability as well as durability against repeated recording. The first magnetic layer and the second magnetic layer are formed by sputtering. At least one of the magnetic layers composing the first magnetic layer and positioned adjacent to the second magnetic layer is formed with a sputter gas pressure greater than the sputter gas pressure applied when forming a magnetic layer composing the second magnetic layer and positioned adjacent to the first magnetic layer.

Magneto-optical recording medium production method

This invention provides a method for producing a magneto-optical recording medium with a laminated film composed of a plurality of magnetic layers made of alloys of rare earth metals-transition metals such as a magneto-optical recording medium allowing direct overwriting through light intensity modulation and a magneto-optical recording medium allowing magnetically induced recording with super resolution, or a method for stably producing a magneto-optical recording medium excellent in performance. The method consists of using, as vaporizers to form the laminated magnetic film, three or more vaporizers including one or more vaporizers containing mainly rare earth elements and one or more vaporizers containing mainly transition metals. Then, particles ejected from a vaporizer containing mainly a rare earth metal and from two or more vaporizers containing mainly transition metals are allowed to continue to impinge onto the surface upon which the laminated film is to be formed, throughout the formation of the laminated film.

Method for producing a magneto-optical recording medium

An optical disk recording medium includes a single layer disk substrate having a hub provided on one side which includes a circular magnetic plate for effecting chucking of the optical disk. On the opposite side of the disk substrate a reinforcing plate is attached for reducing disk warpage during chucking, loading etc. The circular magnetic plate includes a centering opening for disk chucking, while a center opening of the reinforcing plate is larger in diameter than the centering opening. The reinforcing plate covers a central opening formed in the disk substrate and includes a boss portion which is projected into the opening. A groove is provided in the reinforcing plate at the outer circumference of the boss portion for retaining excess adhesive when the substrate is affixed to the reinforcing plate.

Growing community of inventors

Miyagi, Japan

Masatsugu Suwabe