Patent EP0083991A2 successfully refreshed from Google Patents.
EP0083991A2
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EP
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Optical type information recording medium
Assignee: Fujitsu Ltd
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Filing: 1983-01-11
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Granted: —
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Expires: 2003-01-11
Abstract
Abstract An optical type information recording medium suitable for writing and reading information by irradiating a photobeam on a recording material layer formed on a substrate. This recording medium comprises a protective coating layer essentially composed of a porphyrin type compound such as copper phthalocyanine and formed on at least the surface of the recording material layer opposite to the substrate. This recording medium has an satisfactory water vapour resistance which does not substantially impair the recording sensitivity.
Inventors
- 👤 Yasuyuki Goto
- 👤 Nagaaki Koshino
- 👤 Hironori Goto
- 👤 Koichi Nichimo Hiyoshi Dai-3 Ogawa
- 👤 Seiyo Ogawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 20:17
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/254; G11B7/2542; G11B7/242; G11B7/243; G11B2007/24302; G11B2007/2431; G11B2007/24314; G11B2007/24316; G11B7/257; G11B7/2572
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
75 words
An optical type information recording medium suitable for writing information by irradiating a photobeam on a recording material layer to cause a physical change in the recording material layer and that comprises a substrate, the recording material layer formed on the substrate and a protective coating layer formed on at least the surface of the recording material layer opposite to the substrate, characterised in that the protective coating is formed of a porphyrin type compound.
Claim 2
Dependent Claim
75 words
An optical type information recording medium suitable for writing information by irradiating a photobeam on a recording material layer to cause a physical change in the recording material layer and that comprises a substrate, the recording material layer formed on the substrate and a protective coating layer formed on at least the surface of the recording material layer opposite to the substrate, characterised in that the protective coating is formed of a porphyrin type compound.
Claim 3
Dependent Claim
21 words
A recording medium according to claim 1 characterised in that the protective coating consists substantially only of the porphyrin type compound.
Claim 4
Dependent Claim
20 words
A recording medium according to claim 1 or claim 2 characterised in that the porphyrin type compound is a tetrabenztetrazaporphine.
Claim 5
Dependent Claim
30 words
A recording medium according to any preceding claim characterised in that the porphyrin type compound is copper phthalocyanine, lead phthalocyanine, cobalt phthalocyanine, iron phthalocyanine, vanadium phthalocyanine or a mixture thereof.
Claim 6
Dependent Claim
22 words
A recording medium according to any preceding claim characterised, in that the thickness of the protective coating is at least 5 nm.
Claim 7
Dependent Claim
36 words
A recording medium according to any preceding claim characterised in that the recording material layer is composed of Te, Bi, In, Se, As, Pb, Sn or an alloy or mixture of two or more of these.
Claim 8
Dependent Claim
24 words
A recording medium according to any preceding claim characterised in that the recording material is Te and the porphyrin type compound is copper phthalocyanine.
References Cited (Backward Citations)
No citation records indexed.
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