Patent US4668549A successfully refreshed from Google Patents.
US4668549A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optically readable information disc
Assignee: US Philips Corp
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Filing: 1986-02-03
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Granted: 1987-05-26
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Expires: 2006-02-03
Abstract
Abstract Optically readable information disc having a substrate plate manufactured by an injection moulding process or a compression moulding process and composed of a mixture of 40-90% by weight of polymethylmethacrylate and 10-60% by weight of polyvinylchloride or chlorinated polyvinylchloride.
Inventors
- 👤 Gerardus J. M. Lippits
- 👤 Petrus E. J. Legierse
- 👤 George J. P. Dujardin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:48
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/253; G11B7/2533; G11B7/242; G11B7/243; G11B7/2433; G11B7/2534; G11B7/258; G11B7/2585; G11B7/259; Y; Y10; Y10S; Y10S430/00; Y10S430/146
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
89 words
An optically readable information disc comprising a substrate plate in the form of a disc manufactured from a synthetic resin and which comprises on one or both sides a reflecting optical structure which is read by means of laser light via the substrate plate, characterized in that the substrate plate is a body which is manufactured by means of an injection moulding process or a compression moulding process and is composed of a mixture of 40-80% by weight of polymethylmethacrylate and 20-60% by weight of polyvinylchloride or chlorinated polyvinylchloride.
Claim 2
Dependent Claim
89 words
An optically readable information disc comprising a substrate plate in the form of a disc manufactured from a synthetic resin and which comprises on one or both sides a reflecting optical structure which is read by means of laser light via the substrate plate, characterized in that the substrate plate is a body which is manufactured by means of an injection moulding process or a compression moulding process and is composed of a mixture of 40-80% by weight of polymethylmethacrylate and 20-60% by weight of polyvinylchloride or chlorinated polyvinylchloride.
Claim 3
Dependent Claim
82 words
An optically readable information disc comprising a substrate plate in the form of a disc manufactured from a synthetic resin and which comprises on one or both sides a reflecting optical structure which is read by means of laser light via the substrate plate, characterized in that the substrate plate is manufactured by means of an injection moulding process or a compression moulding process and is composed of a mixture of 40-80% by weight of polymethylmethacrylate and 20-60% by weight of polyvinylchloride.
Claim 4
Dependent Claim
82 words
An optically readable information disc comprising a substrate plate in the form of a disc manufactured from a synthetic resin and which comprises on one or both sides a reflecting optical structure which is read by means of laser light via the substrate plate, characterized in that the substrate plate is manufactured by means of an injection moulding process or a compression moulding process and is composed of a mixture of 40-80% by weight of polymethylmethacrylate and 20-60% by weight of polyvinylchloride.
Claim 5
Dependent Claim
82 words
An optically readable information disc comprising a substrate plate in the form of a disc manufactured from a synthetic resin and which comprises on one or both sides a reflecting optical structure which is read by means of laser light via the substrate plate, characterized in that the substrate plate is manufactured by means of an injection moulding process or a compression moulding process and is composed of a mixture of 40-60% by weight of polymethylmethacrylate and 60-40% by weight of polyvinylchloride.
Claim 6
Dependent Claim
82 words
An optically readable information disc comprising a substrate plate in the form of a disc manufactured from a synthetic resin and which comprises on one or both sides a reflecting optical structure which is read by means of laser light via the substrate plate, characterized in that the substrate plate is manufactured by means of an injection moulding process or a compression moulding process and is composed of a mixture of 40-60% by weight of polymethylmethacrylate and 60-40% by weight of polyvinylchloride.
References Cited (Backward Citations)
US4423427A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-05-25 | 1990-11-24 | 1991-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-05-25 | 1994-11-24 | 1995-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-05-25 | 1998-11-24 | 1999-05-26 | $7700.00 | Window Closed / Lapsed |