US3929496A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High alumina ceramic insulator compositions
Assignee: Niterra Co Ltd
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Filing: 1975-01-20
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Granted: 1975-12-30
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Expires: 1995-01-20
Abstract
Abstract A high alumina ceramic composition having improved thermal and mechanical properties consists of 80 to 98 percent by weight of alumina of a main constituent and 2 to 20 percent by weight of an accessory constituent, which consists of a mixture of SiO2, B2O3 and at least one oxide (RO) selected from the group consisting of alkaline earth metal oxides and bivalent metal oxides, said mixture having a composition range encircled with points A, B, C and D in a triangular coordinate.
Inventors
- 👤 Toshiyasu Asano
- 👤 Kazuyoshi Sumi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 04:09
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/111; H; H01; H01B; H01B19/00; H01B3/00; H01B3/02; H01B3/025
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
109 words
AN ALUMINA CERAMIC INSULATOR FOR USE IN A SPARK PLUG, FORMED BY SINTERING AT A TEMPERATURE OF 1410*C TO 1700*C A MIXTURE OF 80 TO 98 PERCENT BY WEIGHT OF ALUMINA OF A MAIN CONSTITUENT AND 2 TO 20 PERCENT BY WEIGHT OF FLUX MATERIAL OF AN ACESSORY CONSTITUENT CONSISTING OF SIO2, B2O3 AND AT LEAST ONE OXIDE (RO) SELECTED FROM THE GROUP CONSISTING OF ALKALINE EARTH METAL OXIDES OF CAO, MGO, BAO, SRO AND BEO AND BIVALENT METAL OXIDES OF NIO CDO, ZNO, MNO, CRO AND SNO, SAID FLUX MATERIAL HAVING THE FOLLOWING COMPOSITION RANGE ENCIRCLED WITH THE POINTS A, B, C AND D IN THE TRIANGULAR COORDINATE:
Claim 2
Dependent Claim
109 words
AN ALUMINA CERAMIC INSULATOR FOR USE IN A SPARK PLUG, FORMED BY SINTERING AT A TEMPERATURE OF 1410*C TO 1700*C A MIXTURE OF 80 TO 98 PERCENT BY WEIGHT OF ALUMINA OF A MAIN CONSTITUENT AND 2 TO 20 PERCENT BY WEIGHT OF FLUX MATERIAL OF AN ACESSORY CONSTITUENT CONSISTING OF SIO2, B2O3 AND AT LEAST ONE OXIDE (RO) SELECTED FROM THE GROUP CONSISTING OF ALKALINE EARTH METAL OXIDES OF CAO, MGO, BAO, SRO AND BEO AND BIVALENT METAL OXIDES OF NIO CDO, ZNO, MNO, CRO AND SNO, SAID FLUX MATERIAL HAVING THE FOLLOWING COMPOSITION RANGE ENCIRCLED WITH THE POINTS A, B, C AND D IN THE TRIANGULAR COORDINATE:
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-29 | 1979-06-30 | 1979-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-29 | 1983-06-30 | 1983-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-29 | 1987-06-30 | 1987-12-30 | $7700.00 | Window Closed / Lapsed |