US4057831A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Video record disc manufactured by a process involving chemical or sputter etching
Assignee: US Philips Corp
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Filing: 1976-08-11
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Granted: 1977-11-08
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Expires: 1996-08-11
Abstract
Abstract A mother for manufacturing long-playing video records is provided by (1) selectively exposing a photoresist disposed as the outer layer on a substrate comprising a disc-shaped plate, a thin layer of base material, e.g., an oxide of nitride, adhering to the plate and a thin metal layer, e.g., chromium, silver, nickel or titanium, coating the base material layer, (2) removing non-activated sections of the photoresist layer and (3) sputter or chemically etching the thin metal and base material layers in sections corresponding to the removed sections of the photoresist layer.
Inventors
- 👤 Bernardus Antonius Johannus Jacobs
- 👤 Johannes Van der Wal
- 👤 Gerrit Berend Gerritsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:16
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/26; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24802; Y10T428/24851; Y10T428/24868; Y10T428/24917; Y10T428/24926; Y10T428/249921; Y10T428/249922
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
71 words
A disc-shaped information carrier comprising a disc-shaped plate and a substantially spiral information-providing track on a surface of said plate produced by subjecting a tightly adhering thin layer of base material disposed on said plate and a thin metal layer coating said base material layer to a sputter etching process to selectively remove portions of the thin metal layer and the underlying base material layer from the surface of said plate.
Claim 2
Dependent Claim
71 words
A disc-shaped information carrier comprising a disc-shaped plate and a substantially spiral information-providing track on a surface of said plate produced by subjecting a tightly adhering thin layer of base material disposed on said plate and a thin metal layer coating said base material layer to a sputter etching process to selectively remove portions of the thin metal layer and the underlying base material layer from the surface of said plate.
Claim 3
Dependent Claim
14 words
Information carrier as claimed in claim 1, wherein the metal layer consists of chromium.
Claim 4
Dependent Claim
15 words
Information carrier as claimed in claim 1, wherein the plate is a flat glass plate.
Claim 5
Dependent Claim
25 words
Information carrier as claimed in claim 3, wherein the thin film consists of an oxide or a nitride, in particular silicon oxide or indium oxide.
References Cited (Backward Citations)
US3287563A
Cited
US3560280A
Cited
US3534166A
Cited
US3642548A
Cited
US3688025A
Cited
US3919066A
Cited
US3957609A
Cited
US3984300A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-11-07 | 1981-05-09 | 1981-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-11-07 | 1985-05-09 | 1985-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-11-07 | 1989-05-09 | 1989-11-08 | $7700.00 | Window Closed / Lapsed |