Patent US3380607A successfully refreshed from Google Patents.
Patent EP0227981A2 successfully refreshed from Google Patents.
EP0227981A2
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EP
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Production method of an optical recording medium
Assignee: Hitachi Ltd
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Filing: 1986-12-06
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Granted: —
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Expires: 2006-12-06
Abstract
Abstract In an optical recording medium, an under layer is formed between an even pattern of a substrate and a recording layer, and said under layer is made of a high polymeric material which can be melted, sublimated, or decomposed at a lower temperature than the melting point, the sublimating point, or the decomposing temperature of said recording layer. Accordingly, said under layer can relax the thermal shock transferred from said substrate into said recording layer, and the deformation of said substrate can be prevented, even though a laser beam for playback is repeatedly radiated onto said recording layer, and said optical recording medium has a larger recording sensitivity than the recording sensitivity of an optical recording disc of a prior art.
Inventors
- 👤 Akira Gotoh
- 👤 Yukinobu Yamazaki
- 👤 Naoyuki Kikuchi
- 👤 Shinkichi Horigome
- 👤 Motoyasu Terao
- 👤 Hiroyuki Suzuki
- 👤 Makoto Kito
- 👤 Yuichi Kokaku
- 👤 Mitsuru Shimizu
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 14:00
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/257; G11B7/2572; G11B7/2575; G11B7/26; G11B7/242; G11B7/243; G11B2007/24302; G11B2007/24312; G11B2007/24316; G11B7/253; G11B7/2533; G11B7/2534; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10S430/00; Y10S430/146; Y10T; Y10T428/00; Y10T428/26; Y10T428/261; Y10T428/266; Y10T428/31504; Y10T428/31507; Y10T428/31511; Y10T428/3154; Y10T428/31544; Y10T428/31678; Y10T428/31681; Y10T428/31692; Y10T428/31721; Y10T428/31786; Y10T428/31826; Y10T428/3183
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
81 words
An optical recording medium comprising: a substrate; a recording layer provided on said substrate, and made of a material having a first temperature at which said material of said recording layer can be melted, sublimated or decomposed; and an under layer formed between said substrate and said recording layer, and made of a high polymeric material having a second temperature at which said high polymeric material can be melted, sublimated, or decomposed, said second temperature being lower than said first temperature.
Claim 2
Dependent Claim
81 words
An optical recording medium comprising: a substrate; a recording layer provided on said substrate, and made of a material having a first temperature at which said material of said recording layer can be melted, sublimated or decomposed; and an under layer formed between said substrate and said recording layer, and made of a high polymeric material having a second temperature at which said high polymeric material can be melted, sublimated, or decomposed, said second temperature being lower than said first temperature.
Claim 3
Dependent Claim
19 words
The optical recording medium as defined in claim 1, wherein said high polymeric material is fluorocarbon resin or polyimide.
Claim 4
Dependent Claim
16 words
The optical recording medium as defined in claim 2, wherein said high polymeric material is transparent.
Claim 5
Dependent Claim
21 words
The optical recording medium as defined in claim 1, wherein said high polymeric material includes fluorine and carbon and is transparent.
Claim 6
Dependent Claim
29 words
The optical recording medium as defined in claim 4, wherein said high polymeric material is at least one compound of polyolefine fluoride, halogenide of polyolefine fluoride, and graphite fluoride.
Claim 7
Dependent Claim
34 words
The optical recording medium as defined in claim 4, wherein said high polymeric material is at least one compound of polytetrafluoroethylene, polyvinyl fluoride, polytrifluoroethylene, polyvinylidene fluoride, polyhexafluoropropylene, polychlorotrifluoroethylene, polydichlorodifluoroethylene, polycarbon monofluoride, and polydicarbon monofluoride.
Claim 8
Dependent Claim
37 words
The optical recording medium as defined in claim 1, wherein said high polymeric material has a heat resistance superior to said substrate and a lower heat conductivity than said substrate, and said high polymeric material is transparent.
Claim 9
Dependent Claim
39 words
The optical recording medium as defined in claim 7, wherein said high polymeric material has a heat resistance resisting at a higher temperature than 110 °C, and said high polymeric material has a lower heat conductivity than 5 W/mK.
Claim 10
Dependent Claim
21 words
The optical recording medium as defined in claim 7, wherein the thickness of said under layer is larger than 200 A.
Claim 11
Dependent Claim
38 words
The optical recording medium as defined in claim 1, wherein said substrate is made of polycarbonate, polymethylmethacrylate or epoxy resin, and said recording layer is made of an alloy having a low melting point and mainly including Te.
Claim 12
Dependent Claim
60 words
A production method of an optical recording medium comprising a process of forming an under layer on an uneven pattern of a substrate on a predetermined vacuum condition in a tank, and a process of forming a recording layer on said under layer on the predetermined vacuum condition in said tank continuously after the process of forming said under layer.
Claim 13
Dependent Claim
60 words
A production method of an optical recording medium comprising a process of forming an under layer on an uneven pattern of a substrate on a predetermined vacuum condition in a tank, and a process of forming a recording layer on said under layer on the predetermined vacuum condition in said tank continuously after the process of forming said under layer.
Claim 14
Dependent Claim
84 words
The production method of the optical recording medium, wherein in the process of forming said under layer, after the gas pressure of said tank is adjusted to a predetermined value, said under layer is formed on said substrate using the material of said under layer as a target by the sputtering method, and in the process of forming said recording layer, said recording layer is formed on said under layer using the material of said recording layer as a target by the sputtering method.
Claim 15
Dependent Claim
84 words
The production method of the optical recording medium, wherein in the process of forming said under layer, after the gas pressure of said tank is adjusted to a predetermined value, said under layer is formed on said substrate using the material of said under layer as a target by the sputtering method, and in the process of forming said recording layer, said recording layer is formed on said under layer using the material of said recording layer as a target by the sputtering method.
References Cited (Backward Citations)
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