EP0467705A1
Expired / Lapsed
EP
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Optical disk
Assignee: Sharp Corp
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Filing: 1991-07-19
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Granted: —
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Expires: 2011-07-19
Abstract
Abstract An optical disk including a transparent plastic substrate, a recording film formed on an one side surface of said substrate, a first protective film covering said recording film, and a moisture-impermeable film formed on the other side surface of said substrate via or not via an intermediate film.
Inventors
- 👤 Kenji Ohta
- 👤 Toshikazu Nagaura
- 👤 Masayasu Futagawa
- 👤 Shinji Yamagami
- 👤 Yoshiteru Murakami
- 👤 Hiroyuki Ikenaga
- 👤 Michinobu Mieda
- 👤 Tetsuya Inui
- 👤 Akira Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 16:44
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/254; G11B7/2542; G11B11/00; G11B11/10; G11B11/105; G11B11/10582; G11B11/10586; G11B7/26; G11B7/242; G11B7/243; G11B2007/24302; G11B2007/24306; G11B7/257; G11B2007/25705; G11B2007/25708; G11B2007/25713; G11B7/253; G11B7/2533; G11B7/2534; G11B7/258; G11B7/2585
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
47 words
An optical disk comprising a transparent plastic substrate, a recording film formed on one side surface of said substrate, a first protective film covering said recording film, and a moisture-impermeable film formed on the other side surface of said substrate via or not via an intermediate film.
Claim 2
Dependent Claim
34 words
An optical disk as set forth in claim 1, wherein the moisture-impermeable film is further covered with a second protective film made of substantially the same material as that of the first protective film.
Claim 3
Dependent Claim
42 words
An optical disk as set forth in claim 1 or 2, wherein the first protective film and the moisture-impermeable film or the second protective film are each further coated with a synthetic resin film containing a powder of a transparent conductive material.
Claim 4
Dependent Claim
20 words
An optical disk as set forth in claims 1, wherein the moisture-impermeable film is made of polyvinylidene chloride or polytrifluorochloroethylene.
Claim 5
Dependent Claim
23 words
An optical disk as set forth in claims 1, wherein the moisture-impermeable film is made of SiO₂, SiO, Al₂O₃, SiN, SiAON or AlN.
Claim 6
Dependent Claim
21 words
An optical disk as set forth in claims 1, wherein the moisture-impermeable film is a AlN film of 1-20 nm thick.
Claim 7
Dependent Claim
27 words
An optical disk as set forth in claims 1, wherein the moisture-impermeable film is made of polyvinylidende chloride or polytrifluorochloroethylene and has a thickness of 2-20 µm.
Claim 8
Dependent Claim
21 words
An optical disk as set forth in claims 1, wherein the intermediate film is made of a UV-setting urethane acrylate resin.
Claim 9
Dependent Claim
33 words
An optical disk as set forth in claim 1 or 2, wherein the first protective film and the second protective film are made of a UV-setting urethane acrylate resin, polyvinylidene chloride or polytrifluorochloroethylene.
Claim 10
Dependent Claim
35 words
An optical disk as set forth in claim 1 or 2, wherein the first protective film and the second protective film are made of a synthetic resin containing a powder of a transparent conductive material.
Claim 11
Dependent Claim
28 words
An optical disk as set forth in claim 3 or claim 10, wherein the powder of the transparent conductive material is made of SiO₂, SnO₂-Sb₂O₅, In₂O₃ or In₂O₃-SnO₂.
Claim 12
Dependent Claim
41 words
An optical disc which has a protective film (3) over a recording layer (7) disposed on one side of a substrate (1), and wherein to reduce warpage a moisture-impermeable film (4) is provided on the other side of the substrate (1).
References Cited (Backward Citations)
No citation records indexed.
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