Patent US2520805A successfully refreshed from Google Patents.
US2520805A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Carboxy alkyl cellulose impression materials and impressions made therefrom
Assignee: Ellis Foster Co
•
Filing: 1948-03-30
•
Granted: 1950-08-29
•
Expires: 1968-03-30
Abstract
No abstract record available.
Inventors
- 👤 Joy Homer Van Beuren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:52
CPC Classifications
C; C08; C08B; C08B11/00; C08B11/20; A; A61; A61K; A61K6/00; A61K6/90
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
47 words
AN IMPRESSION MATERIAL CONTAINING A WATERSOLUBLE SALT OF A CARBOXY ALKYL CELLULOSE IN A MIXTURE WITH A SETTING AGENT OF A SALT OF A METAL FORMING A GEL WITH THE CARBOXY ALKYL CELLULOSE, IN PROPORTIONS TO GIVE A GEL STRUCTURE WHEN SET FROM A PASTE WITH WATER.
Claim 2
Dependent Claim
47 words
AN IMPRESSION MATERIAL CONTAINING A WATERSOLUBLE SALT OF A CARBOXY ALKYL CELLULOSE IN A MIXTURE WITH A SETTING AGENT OF A SALT OF A METAL FORMING A GEL WITH THE CARBOXY ALKYL CELLULOSE, IN PROPORTIONS TO GIVE A GEL STRUCTURE WHEN SET FROM A PASTE WITH WATER.
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) | 1953-08-28 | 1954-02-27 | 1954-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-08-28 | 1958-02-27 | 1958-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-08-28 | 1962-02-27 | 1962-08-29 | $7700.00 | Window Closed / Lapsed |