Patent US2939813A successfully refreshed from Google Patents.
US2939813A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pulping of lignocellulosic material
Assignee: Columbia Cellulose Co Ltd
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Filing: 1956-04-25
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Granted: 1960-06-07
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Expires: 1976-04-25
Abstract
No abstract record available.
Inventors
- 👤 Wayman Morris
- 👤 Gordon R Harris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:59
CPC Classifications
D; D21; D21C; D21C3/00; D21C3/003
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
47 words
PROCESS WHICH COMPRISES PULPING WOOD PARTICLES SELECTED FROM THE GROUP CONSISTING OF WOOD WAFERS IN WHCH NO PORTION OF THE WOOD IS MORE THAN 0.015 INCH FROM A SURFACE THEREOF AND DEFIBERED WOOD WITH PERACETIC ACID HAVING A CONCENTRACTION OF BETWEEN ABOUT 10 AND 40% BY WEIGHT.
Claim 2
Dependent Claim
47 words
PROCESS WHICH COMPRISES PULPING WOOD PARTICLES SELECTED FROM THE GROUP CONSISTING OF WOOD WAFERS IN WHCH NO PORTION OF THE WOOD IS MORE THAN 0.015 INCH FROM A SURFACE THEREOF AND DEFIBERED WOOD WITH PERACETIC ACID HAVING A CONCENTRACTION OF BETWEEN ABOUT 10 AND 40% BY WEIGHT.
References Cited (Backward Citations)
US2394989A
Cited
US2511096A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-06-07 | 1963-12-07 | 1964-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-06-07 | 1967-12-07 | 1968-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-06-07 | 1971-12-07 | 1972-06-07 | $7700.00 | Window Closed / Lapsed |