GB2026346A - Recording material and process for the preparation thereof - Google Patents

Recording material and process for the preparation thereof Download PDF

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Publication number
GB2026346A
GB2026346A GB7923263A GB7923263A GB2026346A GB 2026346 A GB2026346 A GB 2026346A GB 7923263 A GB7923263 A GB 7923263A GB 7923263 A GB7923263 A GB 7923263A GB 2026346 A GB2026346 A GB 2026346A
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GB
United Kingdom
Prior art keywords
recording material
substrate
polymer layer
type polymers
polymer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB7923263A
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GB2026346B (en
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Hitachi Ltd
Original Assignee
Hitachi Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hitachi Ltd filed Critical Hitachi Ltd
Publication of GB2026346A publication Critical patent/GB2026346A/en
Application granted granted Critical
Publication of GB2026346B publication Critical patent/GB2026346B/en
Expired legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/252—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers
    • G11B7/257—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of layers having properties involved in recording or reproduction, e.g. optical interference layers or sensitising layers or dielectric layers, which are protecting the recording layers
    • G11B7/2572—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of layers having properties involved in recording or reproduction, e.g. optical interference layers or sensitising layers or dielectric layers, which are protecting the recording layers consisting essentially of organic materials
    • G11B7/2575—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of layers having properties involved in recording or reproduction, e.g. optical interference layers or sensitising layers or dielectric layers, which are protecting the recording layers consisting essentially of organic materials resins
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
    • G11B7/243—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising inorganic materials only, e.g. ablative layers
    • G11B2007/24302—Metals or metalloids
    • G11B2007/24314—Metals or metalloids group 15 elements (e.g. Sb, Bi)
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/242—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers
    • G11B7/243—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of recording layers comprising inorganic materials only, e.g. ablative layers
    • G11B2007/24302—Metals or metalloids
    • G11B2007/24316—Metals or metalloids group 16 elements (i.e. chalcogenides, Se, Te)
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/241—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material
    • G11B7/252—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers
    • G11B7/253—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of substrates
    • G11B7/2533—Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the selection of the material of layers other than recording layers of substrates comprising resins

Landscapes

  • Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
  • Optical Record Carriers And Manufacture Thereof (AREA)
  • Thermal Transfer Or Thermal Recording In General (AREA)
  • Laminated Bodies (AREA)
  • Manufacturing Optical Record Carriers (AREA)
  • Photoreceptors In Electrophotography (AREA)

Abstract

A recording material which provides an improved signal to noise ratio in the reproduction of a signal recorded on it comprises a plastics substrate 1, a recording film 3 formed on the plastics substrate the shape of which, or some property of which, is affected, by irradiation, and a non-photosensitive polymer layer 2 interposed between the substrate 1 and the recording film 3. The polymer layer 2 is able to accommodate depressions and protrusions in the surface of the substrate 1 and yet provide a smooth surface to receive the recording film 3. This smoothness results in a much improved signal/noise ratio in the reproduced recorded signal. The polymer layer 2 preferably is composed of a rubber type polymer such as cyclized natural rubber and is between 0.2 and 1 ???m thick. <IMAGE>

Description

SPECIFICATION Recording material and process for the preparation thereof The present invention relates to a recording material in which video or sound signals or other information such as electronic computer data can be recorded on a recording film formed on a predetermined substrate by processing beams such as laser beams, and to a process for the preparation of such a recording material.
Conventional recording materials of this type, comprise a glass substrate having a recording film formed on it. To record information on this film holes or depressions are formed in it by processing beams such as laser beams or, alternatively, the properties of the light-exposed area are changed by its exposure, for example, the light-exposed area is rendered soluble in an alkali solution, and can then be removed by etching.
Such recording material is described in detail in, for example, Japanese Patent Application No. 64905/77.
However, recording material which includes a glass substrate is easily broken during storage or during the recording or reading of information. To avoid this, a plastics material can be used as the substrate. However, although the surface of a glass substrate can easily be made smooth by mirror finishing, this is not possible with a plastics substrate.
Because of this, fine-scale protrusions and depressions are present in the surface of the plastic substrate so that corresponding finescale irregularities are produced in the surface of the recording film, resulting in the generation of noise and reduction of the signal/noise (S/N) ratio in the reproduced signal. An example of the known type of recording material which seeks to solve this problem is described in U.S. Patent No. 4,032,691.
The present invention seeks to provide an improved recording material, and a process for the preparation thereof, by providing a recording material including a substrate which is surface-treated so that the S/N ratio of a reproduced signal is not influenced by the surface roughness of the substrate.
Thus according to the present invention there is provided a recording material comprising a plastics substrate and a recording film, the shape or some property of which film is changed when it is subjected to irradiation with a processing beam, wherein a polymer layer having a smooth surface at its side remote from the substrate and composed of non-photosenstive polymer is disposed between said recording film and said substrate.
The material of the invention will now be discussed with reference to Figs. 1, 2 and 3 of the accompanying drawings, which are sectional views of one embodiment of the present invention.
Referring to Fig. 1, the recording material of the present invention is constructed by forming a polymer layer 2 having a smooth surface on a plastics substrate 1 and forming a recording film 3 on this polymer layer 2.
Accordingly, as shown in Fig. 2, even if protrusions and depressions are present on the surface of the plastics substrate 1, because of the presence of the intermediate polymer layer 2, the surface of the recording film 3 can be made smooth. Information can be recorded by any of the usual methods, and a material bearing recorded information, e.g.
as shown in Fig. 3, is thus obtained.
U.S. Patent No. 4,032,691 discloses a recording material including a porous resin layer interposed between a substrate and a recording film. However, this resin layer has a fibrous, porous, honeycomb, grid or other similar structure, and its surface is not smooth so that improvement in the S/N ratio cannot be expected.
In the present invention, the material of which the plastics substrate is composed is not particularly critical, but it preferably has a softening point higher than 40 C. Particular examples are a methacrylic resin, a vinyl chloride resin or a polystyrene resin.
In the recording material of the present invention, the polymer layer 2 is composed of a non-photosensitive polymer. When a photosensitive polymer is used, the S/N ratio is improved just after manufacture, but the polymer is sensitized by natural light or environmental illumination so that the cross-linking reaction is accelerated, causing shrinking or swelling, with the result that the improved S/N ratio cannot be maintained.
In the present invention, it is preferred that the non-photosensitive polymer be at least one of rubber type polymers, vinyl polymers, carbonic acid ester type polymers, cellulose type polymers, epoxy type polymers, phenol type polymers, urea type polymers and alkyd type polymers. Examples of these are as follows: As a rubber type polymer, a cyclized rubber type polymer such as, for example, cyclized natural rubber or cyclized polyisoprene is especially preferred.
Suitable vinyl type polymers include polyvinyl alcohol, polyvinyl chloride and polyvinyl butyral.
A A suitable carbonic acid ester type polymer is a polycarbonate of bisphenol A.
Suitable cellulose type polymers, include cellulose acetate, cellulose acetate butyrate and cellulose propionate.
A A suitable epoxy type polymer is polyglycidyl methacrylate.
A suitable phenol type polymer is a phenolformaldehyde resin.
A suitable urea type polymer is polyurea.
A A suitable alkyd type polymer is a glycerin phthalic acid resin.
In the present invention, the term "poly mer is used in a broad sense, including not only a homopolymer of the constituent monomer but also a copolymer of the constituent monomer with another comonomer.
Among the above-mentioned polymers, a rubber type polymer is especially preferred because it exerts a buffering action when the thermal expansion coefficient of the plastics substrate is different from that of the recording film.
In the recording material of the present invention, the thickness of the polymer layer 2 should preferably be from 0.01 to 10 ym, more preferably from 0.1 to 1 ym, and most preferably from 0.2 to 1 jbm. This is for the following reasons.
If the thickness of the polymer layer is at least 0.01 jum, depressions and the like present on the surface of the substrate can be sufficiently filled in to achieve the intended effect of the present invention. However, ordinary substrates, particularly commercially available plastics plates, have protrusions and depressions of about 0.1 #m size on the surface thereof, quite apart from any actual damage of the surface. For this reason, it is particularly preferred that the thickness of the polymer layer be at least 0.1 item, or more preferably at least 0.2 lim to provide a safer margin.Regarding the upper limit of the polymer layer, in order to maintain a uniform thickness of the layer, its preferred thickness is up to 10 jtm, more preferably up to 1 fitm.
In the present invention, metals, semi-metals, alloys thereof, chalcogen compounds and multi-layer films thereof can all be used for the recording film. For example, there can be used Bi, Bi-Se, As-Te, As-Se, Sn-Se, In-Se, As-Te-S and Se-Te-As amorphous substances.
The recording material of the present invention can be prepared, for example, by a process involving coating a plastics substrate with a solution of a non-photosensitive polymer in a solvent by a spin coating or similar method, baking the coating at such a temperature as not to cause thermal deformation and forming a recording film on the baked coating by a known method such as vacuum deposition. In order to obtain a polymer layer which is thin and has a smooth surface, the spin coating method is preferably used.
A method of making a recording material embodying the invention will now be described in detail.
Example A solution of cyclized polyisoprene in a solvent was applied to a commercially available methacrylic resin plate 1 to form a polymer layer 2. The plate was baked at 40 C for 30 minutes, and As20Se80 was vacuum deposited onto the baked polymer layer to form a recording film. When laser beams were used to record onto the recording material the S/N ratio of the reproduced signal was increased to 40 dB, in contrast with the 32 dB attainable using a conventional recording medium.
The reproduced signal can be obtained by reading with beams, such as laser beams, directed onto either the recording film side or the substrate side of the material. With this recording medium of the invention, the S/N ratio was improved whichever side the information was read from.
When polyvinyl alcohol, a polycarbonate of bisphenol A, cellulose acetate, polyglycidyl methacrylate, a phenol-formaldehyde resin, polyurea and a glycerin-phthalic acid resin were each separately used instead of the cyclized polysioprene, the S/N ratio was 40 dB in each case.

Claims (13)

1. A recording material comprising a plastics substrate and a recording film, the shape or some property of which film is changed when it is subjected to irradiation with a processing beam, wherein a polymer layer having a smooth surface at its side remote from the substrate and composed of nonphotosensitive polymer is disposed between said recording film and said substrate.
2. A recording material according to claim 1 wherein the non-photosensitive polymer is at least one material selected from rubber type polymers, vinyl type polymers, carbonic acid ester type polymers, cellulose type polymers, epoxy type polymers, phenol type polymers, urea type polymers and alkyd type polymers.
3. A recording material according to claim 1 1 wherein the non-photosensitive polymer is at least one material selected from cyclized natural rubber, cyclized polyisoprene, polyvinyl alcohol, polyvinyl chloride, polyvinyl butyral, a polycarbonate of bisphenol A, cellulose acetate, cellulose acetate butyrate, cellulose propionate, polyglycidyl methacrylate, a phenol-formaldehyde resin, polyurea and a glycerin-phthalic acid resin.
4. A recording material according to any one of claims 1 to 3 wherein the plastics substrate is composed of a methacrylic resin, a vinyl chloride resin or a polystyrene resin.
5. A recording material according to any one of claims 1 to 4 wherein the thickness of the polymer layer is in the range 0.01 to 10 ,um.
6. A recording material according to claim 5 wherein the thickness of the polymer layer is in the range 0.1 to 1 !lem.
7. A recording material according to claim 6 wherein the thickness of the polymer layer is in the range 0.2 to 1 ym.
8. A recording material according to any one of the preceding claims wherein the recording film is composed of chalcogen glass.
9. A process for the preparation of a recording material which includes the steps of applying and drying a solution of a nonphotosensitive polymer onto a plastics substrate to form a polymer layer having a smooth surface at its side remote from the substrate, and forming on said polymer layer a recording film, the shape or a property of which is to be changed when it is subjected to irradiation with a processing beam.
10. A process according to claim 9 wherein application of the solution of the nonphotosensitive polymer to the substrate is carried out by spin coating.
11. A process according to claim 9 or claim 10 wherein said recording film is formed by vacuum deposition.
12. A recording material substantially as herein described in the Example.
13. A process for the preparation of a recording material substantially as herein described in the Example.
GB7923263A 1978-07-14 1979-07-04 Recording material and proces for the preparation thereof Expired GB2026346B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP8589178A JPS5514504A (en) 1978-07-14 1978-07-14 Recording component

Publications (2)

Publication Number Publication Date
GB2026346A true GB2026346A (en) 1980-02-06
GB2026346B GB2026346B (en) 1982-09-29

Family

ID=13871506

Family Applications (1)

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GB7923263A Expired GB2026346B (en) 1978-07-14 1979-07-04 Recording material and proces for the preparation thereof

Country Status (6)

Country Link
JP (1) JPS5514504A (en)
CA (1) CA1136274A (en)
DE (1) DE2928429A1 (en)
FR (1) FR2431144A1 (en)
GB (1) GB2026346B (en)
NL (1) NL7905426A (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0040664A1 (en) * 1980-05-22 1981-12-02 International Business Machines Corporation Process for preparing a filler and/or pigments containing lacquer composition for recording materials, and the lacquer obtained by this composition
US4461825A (en) * 1981-05-07 1984-07-24 Tokyo Shibaura Denki Kabushiki Kaisha Method for forming resist pattern
EP0119656A1 (en) * 1983-03-17 1984-09-26 Koninklijke Philips Electronics N.V. Optical recording disc
EP0135203A1 (en) * 1983-07-28 1985-03-27 General Electric Company Composition for an optically readable information carrier
EP0751006A1 (en) 1995-06-27 1997-01-02 Agfa-Gevaert N.V. New method for the formation of a heat mode image
EP0758103A1 (en) 1995-08-08 1997-02-12 Agfa-Gevaert N.V. New type of photo-sensitive element and a process of forming a metal image with it
EP0762214A1 (en) 1995-09-05 1997-03-12 Agfa-Gevaert N.V. Photosensitive element comprising an image forming layer and a photopolymerisable layer
EP0846571A1 (en) 1996-12-04 1998-06-10 Agfa-Gevaert N.V. Method for the formation of an improved heat mode image

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2935859A1 (en) * 1978-09-08 1980-03-20 Matsushita Electric Ind Co Ltd OPTICAL RECORDING PART
JPS5538655A (en) * 1978-09-08 1980-03-18 Sumitomo Chem Co Ltd Optical signal recording and reproducing member
US4300227A (en) * 1979-10-17 1981-11-10 Rca Corporation Replicable optical recording medium
US4285056A (en) * 1979-10-17 1981-08-18 Rca Corporation Replicable optical recording medium
FR2490858B1 (en) * 1980-09-25 1986-04-04 Rca Corp OPTICAL RECORDING MEDIUM WITH VARIABLE SENSITIVITY AND DISC CONTAINING INFORMATION, MADE BY USING SUCH MEDIUM
JPS57102930A (en) * 1980-12-19 1982-06-26 Nippon Telegr & Teleph Corp <Ntt> Surface finish of acryl resin substrate
JPS59217243A (en) * 1983-05-24 1984-12-07 Fuji Photo Film Co Ltd Information recording medium
US4600682A (en) * 1984-07-06 1986-07-15 Storage Technology Corporation Optical storage structure
CA1261212A (en) * 1985-11-25 1989-09-26 Laura A. Lewin Method for forming optically smooth polymeric layers

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0040664A1 (en) * 1980-05-22 1981-12-02 International Business Machines Corporation Process for preparing a filler and/or pigments containing lacquer composition for recording materials, and the lacquer obtained by this composition
US4461825A (en) * 1981-05-07 1984-07-24 Tokyo Shibaura Denki Kabushiki Kaisha Method for forming resist pattern
EP0119656A1 (en) * 1983-03-17 1984-09-26 Koninklijke Philips Electronics N.V. Optical recording disc
EP0135203A1 (en) * 1983-07-28 1985-03-27 General Electric Company Composition for an optically readable information carrier
EP0751006A1 (en) 1995-06-27 1997-01-02 Agfa-Gevaert N.V. New method for the formation of a heat mode image
EP0758103A1 (en) 1995-08-08 1997-02-12 Agfa-Gevaert N.V. New type of photo-sensitive element and a process of forming a metal image with it
EP0762214A1 (en) 1995-09-05 1997-03-12 Agfa-Gevaert N.V. Photosensitive element comprising an image forming layer and a photopolymerisable layer
EP0846571A1 (en) 1996-12-04 1998-06-10 Agfa-Gevaert N.V. Method for the formation of an improved heat mode image

Also Published As

Publication number Publication date
CA1136274A (en) 1982-11-23
JPS5514504A (en) 1980-02-01
JPS6333210B2 (en) 1988-07-04
FR2431144A1 (en) 1980-02-08
FR2431144B1 (en) 1982-08-20
NL7905426A (en) 1980-01-16
DE2928429A1 (en) 1980-01-24
GB2026346B (en) 1982-09-29

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PCNP Patent ceased through non-payment of renewal fee

Effective date: 19950704