EP0230024A2
Expired / Lapsed
EP
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Optical recording medium having a stabilized recording layer
Assignee: Panasonic Holdings Corp
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Filing: 1986-12-19
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Granted: —
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Expires: 2006-12-19
Abstract
Abstract An optical recording medium comprising an optically transparent substrate and a recording layer formed on the substrate and comprising a mixture of a photochromic spiropyran and an amphiphatic aliphatic acid or its salt. The aliphatic acid or its salt can stabilize photomerocyanine which is a colored isomer of a photochromic spiropyran. The mixture may further comprise a resin binder.
Inventors
- 👤 Jinsei Miyazaki
- 👤 Eiji Ando
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 09:04
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/685; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/242; G11B7/244; G11B7/246; G11B7/247; G11B7/2475; G11B7/252; G11B7/253; G11B7/2531
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
54 words
An optical recording medium which comprises an optically transparent substrate and a recording layer formed on said substrate, said recording layer comprising a mixture of a photochromic spiropyran having a hydrophobic long-chain alkyl group in the molecule and an amphiphatic compound selected from the group consisting of aliphatic acids and salts of the acids.
Claim 2
Dependent Claim
54 words
An optical recording medium which comprises an optically transparent substrate and a recording layer formed on said substrate, said recording layer comprising a mixture of a photochromic spiropyran having a hydrophobic long-chain alkyl group in the molecule and an amphiphatic compound selected from the group consisting of aliphatic acids and salts of the acids.
Claim 3
Dependent Claim
26 words
An optical recording medium according to Claim 1, wherein said photochromic spiropyran and said amphiphatic compound are mixed in a molar ratio of 1:0.1 to 10.
Claim 4
Dependent Claim
22 words
An optical recording medium according to Claim 1, wherein said recording layer consists of a plurality of Langmuir-Blodgett films of said mixture.
Claim 5
Dependent Claim
99 words
An optical recording medium according to Claim 1, wherein said spiropyran has the general formula in which R₁ and R₂ are independently a lower alkyl group, R₃ represents an alkyl group having at least 10 carbon atoms, X is a single bond or a group of one of the following formulae, -C n H 2n OCO-, -C n H 2n COO-, -C n H 2n NHCO-, -C n H 2n CONH- or -C n H 2n O- wherein n≧ 0, R₄ represents an alkyl group having at least one carbon atom, and Y represents an oxygen or sulfur atom.
Claim 6
Dependent Claim
27 words
An optical recording medium according to Claim 4, wherein R₃ is an alkyl group having from 14 to 24 carbon atoms and X is -CH₂OCO- or -O-.
Claim 7
Dependent Claim
23 words
An optical recording medium according to Claim 1, wherein said amphiphatic compound is an aliphatic acid having from 2 to 30 carbon atoms.
Claim 8
Dependent Claim
19 words
An optical recording medium according to Claim 6, wherein said aliphatic acid has from 14 to 24 carbon atoms.
Claim 9
Dependent Claim
15 words
An optical recording medium according to Claim 6, wherein said aliphatic acid is stearic acid.
Claim 10
Dependent Claim
20 words
An optical recording medium according to Claim 1, wherein said amphiphatic compound is a metal salt of an aliphatic acid.
Claim 11
Dependent Claim
17 words
10 An optical recording medium according to Claim 1, wherein said mixture further comprises a resin binder.
Claim 12
Dependent Claim
15 words
An optical recording medium according to Claim 1, wherein said spiropyran is 6-nitro-1ʹ-octadecyl-8-docosanoyloxy-3ʹ,3ʹ-dimethylspiro[2H-1-benzopyran-2,2ʹ-indoline] or 6-nitro-1ʹ-octadecyl-8-methoxy-3ʹ,3ʹ-dimethylspiro[2H-1-benzopyran-2,2ʹ-indoline].
References Cited (Backward Citations)
No citation records indexed.
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