US3587196A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of polishing soft,water-soluble crystals
Assignee: AT&T Inc
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Filing: 1969-05-09
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Granted: 1971-06-28
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Expires: 1989-05-09
Abstract
Abstract A POLISHING TECHNIQUE FOR SOFT, WATER-SOLUBLE CYRSTALS IS DISCLOSED. THE EDGES OF THE CRYSTAL ARE BEVELED TO PREVENT CRUMBLING, AND THE CRYSTAL IS LAPPED, IN AN ANHYDROUS WET LAPPING STEP AND THEN IN AT LEAST ONE DRY LAPPING STEP. BOTH STEPS EMPLOY A NONFRAYABLE CLOTH, SUCH AS NYLON, EMBEDDED IN A SOFT WAX OR PARAFFIN ON A FLAT SURFACE AND IMPREGNATED IN THE CENTER REGION ONLY WITH AN ABRASIVE OF DIAMETER LESS THAN 0.3 U METERS. THE ABRASIVE IS SUPPLIED IN A SLURRY INCLUDING BENZENE WHICH FLUIDIZES THE WAX IN THE CENTER REGION ONLY. TYPICALLY, THE CRYSTALS TO BE POLISHED HAVE AT LEAST ONE OXYGEN ATOM IN EACH UNIT CELL AND HAVE A HARDENSS LESS THAN 3 MOHS. D R A W I N G
Inventors
- 👤 Frank A Dunn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:34
CPC Classifications
B; B24; B24B; B24B19/00; B24B19/22; B24B19/226; B24B1/00
Claims Analysis
Total Claims: 0
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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) | 1974-06-27 | 1974-12-27 | 1975-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-27 | 1978-12-27 | 1979-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-27 | 1982-12-27 | 1983-06-28 | $7700.00 | Window Closed / Lapsed |