Patent US3663247A successfully refreshed from Google Patents.
US3663247A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Glass
Assignee: US Philips Corp
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Filing: 1969-10-31
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Granted: 1972-05-16
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Expires: 1989-10-31
Abstract
Abstract Glass particularly suitable for use in a secondary emission electrode, after adjustment of the surface conductivity by heating in a reducing atmosphere, and having a composition in percent by weight within the range limited as follows: SiO2 30-70 PbO 6-30 Al2O3 0.5-10 Bi2O3 2-45 B2O3 < OR = 5 CaO+SrO < OR = 8Na2O < OR = 6 MgO 0.5-7 K2O < OR = 10 Sb2O3 < OR = 2.
Inventors
- 👤 Hendrikus Johan Lodewijk Trap
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 07:42
CPC Classifications
H; H01; H01J; H01J43/00; H01J43/04; H01J43/06; H01J43/18; H01J43/24; C; C03; C03C; C03C3/00; C03C3/04; C03C3/076; C03C3/102; C03C3/105
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
53 words
Glass as claimed in claim 1, having a composition within the following limits in percent by weight: SiO2 40-50 PbO 6-30 Al2O3 0.5- 10 Bi2O3 10-45 B2O3 < or = 3 CaO+SrO < or = 4 Na2O < or = 2 MgO 3-6 K2O < or = 3 Sb2O3 < or = 2
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) | 1975-05-16 | 1975-11-15 | 1976-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-16 | 1979-11-15 | 1980-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-16 | 1983-11-15 | 1984-05-16 | $7700.00 | Window Closed / Lapsed |