US2645582A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pencil lead
Assignee: J S STAEDTLER MARS BLEISTIFTFA
•
Filing: 1950-01-16
•
Granted: 1953-07-14
•
Expires: 1970-01-16
Abstract
No abstract record available.
Inventors
- 👤 Loy Georg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:38
CPC Classifications
C; C09; C09D; C09D13/00
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
16 words
A PENCIL LEAD COMPRISING SOOT, GRAPHITE, TALCUM, CALCIUM STEARATE, GUM TRAGACANTH, AND A SURFACE ACTIVE AGENT.
References Cited (Backward Citations)
US358746A
Cited
US452890A
Cited
FR414378A
Cited
GB216420A
Cited
US1832654A
Cited
US1937105A
Cited
US1999549A
Cited
US1970603A
Cited
CH177943A
Cited
US2425804A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-07-13 | 1957-01-12 | 1957-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-07-13 | 1961-01-12 | 1961-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-07-13 | 1965-01-12 | 1965-07-14 | $7700.00 | Window Closed / Lapsed |