US3813231A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sandpaper
Assignee: Gulf Research and Development Co
•
Filing: 1972-07-31
•
Granted: 1974-05-28
•
Expires: 1992-07-31
Abstract
Abstract AN IMPROVED FLEXIBLE ABRASIVE SHEET AND A PROCESS FOR PRODUCING THE SAME IS DISCLOSED. THE FLEXIBLE ABRASIVE SHEET INCLUDES A BACKING OF A COPOLYMER OF ETHYLENE AND ACRYLIC ACID HAVING A MELT INDEX AS DETERMINED BY ASTM TEST NO. D1238-57T OF FROM ABOUT 10 UP TO ABOUT 50 AND CONTAINS FROM ABOUT 15 UP TO ABOUT 20 PERCENT POLYMERIZED ACRYLIC ACID BASED ON THE WEIGHT OF THE COPOLYMER, AND AN ABRASIVE GRIT PARTIALLY EMBEDDED IN THE ETHYLENE-ACRYLIC ACID COPOLYMER BACKING. THE FLEXIBLE ABRASIVE SHEET IS FREE OF ANY ADHESIVE OR BONDING AGENT BETWEEN THE BACKING AND THE ABRASIVE GRIT.
Inventors
- 👤 R Gilbert
- 👤 R Monley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:58
CPC Classifications
B; B24; B24D; B24D11/00
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1977-05-27 | 1977-11-26 | 1978-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-27 | 1981-11-26 | 1982-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-27 | 1985-11-26 | 1986-05-28 | $7700.00 | Window Closed / Lapsed |