Patent US3682686A successfully refreshed from Google Patents.
US3682686A
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Method of manufacturing carbonaceous refractory products
Assignee: Akechi Ceramics Co Ltd
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Filing: 1970-10-21
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Granted: 1972-08-08
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Expires: 1990-10-21
Abstract
Abstract CARBONACEOUS REFRACTORY PRODUCTS MANUFACTURED BY A CONVENTIONAL METHOD IS IMMERSED IN A BATH OF MOLTEN TAR PITCH TO IMPREGNATE THE TAR PITCH INTO THE PORES OF THE PRODUCTS, THE IMPREGNATED PRODUCTS ARE HEATED TO ELEVATED TEMPERATURES TO CARBONIZE THE IMPREGNATED TAR PITCH AND THEN THE SURFACE OF THE PRODUCT IS COVERED WITH A LAYER OF GLAZE.
Inventors
- 👤 Toshio Nakamura
- 👤 Hidekichi Ozeki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:11
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; C04B35/00; C04B35/515; C04B35/52; C04B35/521; C04B41/45; C04B41/52; C04B41/80; C04B41/81; C04B41/89; C21; C21C; C21C5/00; C21C5/28; C21C5/42; C21C5/44; Y; Y10; Y10T; Y10T428/00; Y10T428/30
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-08 | 1976-02-07 | 1976-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-08 | 1980-02-07 | 1980-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-08 | 1984-02-07 | 1984-08-08 | $7700.00 | Window Closed / Lapsed |