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Optical information recording medium having a protective film which can be stripped

Assignee: Sony Corp
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Filing: 1989-12-12
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Granted: 1991-05-28
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Expires: 2009-12-12
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Abstract

Abstract An optical information recording medium having at least a transparent substrate and a recording layer and capable of recording an information by irradiating the recording layer with laser beams from the transparent substrate side, wherein a protective film having hygroscopic property is formed on a light incident surface of the transparent substrate so that it can be stripped therefrom.

Inventors

  • 👤 Yuji Arai
  • 👤 Hiroshi Ogawa
  • 👤 Masahiro Hotori

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 03:52
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/254; G11B7/24097; G11B7/2542; G11B7/242; G11B7/244; G11B7/246; G11B7/247; G11B7/2472; G11B7/253; G11B7/2533; G11B7/2534; G11B7/258; G11B7/2595

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 60 words
An optical information recording medium having at least a transparent substrate and a recording layer which is capable of recording information when irradiated with laser beams from the transparent substrate side, comprising: a protective, hygroscopic, antistatic electricity film formed on a light incident surface of the transparent substrate in such a manner that the protective film can be stripped therefrom.
Claim 2
Dependent Claim 60 words
An optical information recording medium having at least a transparent substrate and a recording layer which is capable of recording information when irradiated with laser beams from the transparent substrate side, comprising: a protective, hygroscopic, antistatic electricity film formed on a light incident surface of the transparent substrate in such a manner that the protective film can be stripped therefrom.
Claim 3
Dependent Claim 21 words
An optical information recording medium according to claim 1, wherein the protective film is made of resin having a hydroxyl group.
Claim 4
Dependent Claim 18 words
An optical information recording medium according to claim 2, wherein the protective film is made of polyvinyl alcohol.
Claim 5
Dependent Claim 36 words
An optical information recording medium according to claim 1 or 2, wherein the protective film is colored by a colorant selected from the group consisting essentially of Rhodamine B, Rhodamine 19, Brilliant Green, and Methyline Blue.
Claim 6
Dependent Claim 22 words
An optical information recording medium according to claim 4, wherein the recording layer is made of an organic dye-based optical recording material.
Claim 7
Dependent Claim 18 words
An optical information recording medium according to claim 1, wherein the protective film includes an electrically conductive material.
Claim 8
Dependent Claim 18 words
An optical information recording medium according to claim 1, wherein the protective film includes a surface active agent.
Claim 9
Dependent Claim 19 words
An optical information recording medium according to claim 1, wherein the protective film includes an amphoteric surface active agent.
Claim 10
Dependent Claim 19 words
An optical information recording medium according to claim 1, wherein the protective film includes a nonionic surface active agent.
Claim 11
Dependent Claim 19 words
An optical information recording medium according to claim 1, wherein the protective film includes an anion surface active agent.
Claim 12
Dependent Claim 19 words
An optical information recording medium according to claim 1, wherein the protective film includes a cation surface active agent.
Claim 13
Dependent Claim 19 words
An optical information recording medium according to claim 1, wherein the protective film includes a cyclohexane-based surface active agent.
Claim 14
Dependent Claim 52 words
An optical information recording medium according to claims 1 or 2, wherein the protective film includes one or more of the following surface active agent compounds: alkyl betaine, alkyl aminoxide, alkyl trimethly ammonium salt, polyoxyethylene alkyl amine, alkyl phosphate, alkyl amine acetate, acrylic acid having a functional group, and methacrylic acid polymer.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-05-27 1994-11-26 1995-05-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-05-27 1998-11-26 1999-05-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-05-27 2002-11-26 2003-05-28 $7700.00 Window Closed / Lapsed

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