US2566753A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Impregnated pencil lead
Assignee: AB Dick Co
•
Filing: 1946-08-08
•
Granted: 1951-09-04
•
Expires: 1966-08-08
Abstract
No abstract record available.
Inventors
- 👤 Jr Charles H Van Dusen
- 👤 Oscar E Weissenborn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 08:47
CPC Classifications
C; C09; C09D; C09D13/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
12 words
A PENCIL LEAD IMPREGNATED WITH A MIXTURE OF CHINA-WOOD OIL AND ROSIN.
Claim 2
Dependent Claim
12 words
A PENCIL LEAD IMPREGNATED WITH A MIXTURE OF CHINA-WOOD OIL AND ROSIN.
References Cited (Backward Citations)
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Cited
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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) | 1954-09-03 | 1955-03-05 | 1955-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-09-03 | 1959-03-05 | 1959-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-09-03 | 1963-03-05 | 1963-09-04 | $7700.00 | Window Closed / Lapsed |