US4405670A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Capacitance electronic disc stamper having improved stain resistance and method for the manufacture thereof
Assignee: RCA Corp
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Filing: 1982-05-28
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Granted: 1983-09-20
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Expires: 2002-05-28
Abstract
Abstract Nickel stampers used for the molding of capacitive electronic discs are treated prior to use in the molding process by heating the stamper in the presence of an oxygen containing gas, at a temperature from about 220 DEG C. to about 300 DEG C. for 2 to 5 hours until a continuous protective oxide layer approximately 10-40 angstroms thick is formed on the surface of the stamper.
Inventors
- 👤 Mohamed E. Labib
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 05:16
CPC Classifications
B; B29; B29C; B29C33/00; B29C33/42; B29C33/424; C; C23; C23C; C23C8/00; C23C8/06; C23C8/08; C23C8/10
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
58 words
An improved stamper for molding a capacitive electronic disc, said stamper being formed of nickel and having an information containing track defined in the molding surface thereof, said molding surface having formed thereon a continuous conformal layer of nickel oxide which is free, to substantially free, of microdefects and which is about 10 to 40 angstroms in thickness.
Claim 2
Dependent Claim
58 words
An improved stamper for molding a capacitive electronic disc, said stamper being formed of nickel and having an information containing track defined in the molding surface thereof, said molding surface having formed thereon a continuous conformal layer of nickel oxide which is free, to substantially free, of microdefects and which is about 10 to 40 angstroms in thickness.
Claim 3
Dependent Claim
23 words
The stampers according to claim 1 wherein the nickel oxide layer on the surface of the stamper is about 40 angstroms in thickness.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-09-19 | 1987-03-21 | 1987-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-19 | 1991-03-21 | 1991-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-19 | 1995-03-21 | 1995-09-20 | $7700.00 | Window Closed / Lapsed |