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Optical recording medium having dual information surfaces

Assignee: Panasonic Holdings Corp
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Filing: 1995-12-27
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Granted: —
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Expires: 2015-12-27
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Abstract

Abstract The optical recording medium of this invention includes: a first substrate having a first information surface; a semitransparent reflection film formed on the first information surface of the first substrate; a second substrate having a second information surface; a reflection film formed on the second information surface of the second substrate; and an adhesive layer for adhering the first substrate and the second substrate so that the first information surface and the second information surface face each other, wherein the thickness of the first substrate is 0.56 mm or more, the thickness of the adhesive layer is 30 µm or more, and the total thickness of the first substrate and the adhesive layer is 0.68 mm or less.

Inventors

  • 👤 Mitsurou Moriya
  • 👤 Hiroshi Taniguchi
  • 👤 Shin-Ichi Tanaka
  • 👤 Michiyoshi Nagashima
  • 👤 Yasuhiro Sugihara

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-09 18:38
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/253; G11B5/00; G11B5/62; C; C09; C09K; C09K21/00; C09K21/14; G11B23/00; G11B23/38; G11B23/40; G11B7/2403; G11B7/24035; G11B7/24038; G11B7/242; G11B7/243; G11B7/254; G11B7/256; G11B7/258; G11B7/26; G11B7/266; G11B2007/24302; G11B2007/24312; G11B2007/24314; G11B2007/24316; G11B7/002; G11B7/0037; G11B7/004; G11B7/0045; G11B7/00454; G11B7/2533; G11B7/257; G11B7/2585; G11B7/2595; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10S430/00; Y10S430/146; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12674; Y10T428/21

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 115 words
An optical recording medium comprising: a first substrate having a first information surface; a semitransparent reflection film formed on the first information surface of the first substrate; a second substrate having a second information surface; a reflection film formed on the second information surface of the second substrate; and an adhesive layer for adhering the first substrate and the second substrate so that the first information surface and the second information surface face each other, wherein the thickness of the first substrate is 0.56 mm or more, the thickness of the adhesive layer is 30 µm or more, and the total thickness of the first substrate and the adhesive layer is 0.68 mm or less.
Claim 2
Dependent Claim 42 words
An optical recording medium according to claim 1, wherein the thickness of the first substrate is in the range of 0.56 mm to 0.6 mm, and the thickness of the adhesive layer is in the range of 40 µm to 60 µm.
Claim 3
Dependent Claim 28 words
An optical recording medium according to claim 1, wherein a recording material film is formed on the reflection film for the second substrate for recording and reproducing information.
Claim 4
Dependent Claim 21 words
An optical recording medium according to claim 3, wherein the recording material film is made of a phase-change type recording material.
Claim 5
Dependent Claim 20 words
An optical recording medium according to claim 1, wherein a label is formed on a surface of the second substrate.
Claim 6
Dependent Claim 75 words
An optical recording medium according to claim 1, wherein a spiral track is formed on each of the first and second substrates, and the direction of the formation of the spiral track on the first substrate is the same as the direction of the formation of the spiral track on the second substrate when the spiral tracks are viewed from the side of a surface of the first substrate opposite to the first information surface.
Claim 7
Dependent Claim 74 words
An optical recording medium according to claim 1, wherein a spiral track is formed on each of the first and second substrates, and the direction of the formation of the spiral track on the first substrate is reverse to the direction of the formation of the spiral track on the second substrate when the spiral tracks are viewed from the side of a surface of the first substrate opposite to the first information surface.
Claim 8
Dependent Claim 102 words
An optical recording medium comprising: a first substrate having a first information surface; a semitransparent reflection film formed on the first information surface of the first substrate; a second substrate having a second information surface; a reflection film formed on the second information surface of the second substrate; and an adhesive layer for adhering the first substrate and the second substrate so that the first information surface of the first substrate faces a surface of the second substrate opposite to the second information surface, wherein the thickness of the first substrate is substantially the same as the thickness of the second substrate.
Claim 9
Dependent Claim 28 words
An optical recording medium according to claim 8, wherein a recording material film is formed between the second information surface of the second substrate and the reflection film.
Claim 10
Dependent Claim 21 words
An optical recording medium according to claim 9, wherein the recording material film is made of a phase-change type recording material.
Claim 11
Dependent Claim 113 words
An optical recording medium comprising: a first substrate having a first information surface; a semitransparent reflection film formed on the first information surface of the first substrate; a second substrate having a second information surface; a reflection film formed on the second information surface of the second substrate; an adhesive layer for adhering the first substrate and the second substrate so that the first information surface of the first substrate faces a surface of the second substrate opposite to the second information surface; and a label formed on the reflection film for the second substrate, wherein the thickness of the first substrate is substantially the same as the thickness of the second substrate.
Claim 12
Dependent Claim 28 words
An optical recording medium according to claim 11, wherein a recording material film is formed between the second information surface of the second substrate and the reflection film.
Claim 13
Dependent Claim 21 words
An optical recording medium according to claim 12, wherein the recording material film is made of a phase-change type recording material.

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