Patent US2941919A successfully refreshed from Google Patents.
US2941919A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sizing of paper
Assignee: Hercules Powder Co
•
Filing: 1957-01-31
•
Granted: 1960-06-21
•
Expires: 1977-01-31
Abstract
No abstract record available.
Inventors
- 👤 Spencer H Watkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:24
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/62
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
113 words
THE PROCESS OF SIZING PAPER WHICH COMPRISES ADDING TO AN AQUEOUS SUSPENSION OF PAPER PULP AN AQUEOUS AND AT LEAST PARTIALLY NEUTRALIZED DISPERSION OF TALL OIL ROSIN, IN AN AMOUNT SUCH AS TO SUPPLY FROM ABOUT 1/4 TO ABOUT 4% OF THE ROSIN, BASED ON THE WEIGHT TO DRY PULP, IN SAID SUSPENSION, SAID TALL OIL ROSIN HAVING BEEN SUBJECTED TO TREATMENT WITH FROM ABOUT 1% TO ABOUT 4%, BASED ON THE WEIGHT OF TALL OIL ROSIN OF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF FORMALDEHYDE AND FORMALDEHYDE-YIELDING MATERIALS, AT A TEMPERATURE OF FROM ABOUT 100*C. TO ABOUT 200*C. IN THE PRESENCE OF AN ACID CATALYST PRIOR TO SAPONIFICATION WITH AQUEOUS ALKALI.
Claim 2
Dependent Claim
113 words
THE PROCESS OF SIZING PAPER WHICH COMPRISES ADDING TO AN AQUEOUS SUSPENSION OF PAPER PULP AN AQUEOUS AND AT LEAST PARTIALLY NEUTRALIZED DISPERSION OF TALL OIL ROSIN, IN AN AMOUNT SUCH AS TO SUPPLY FROM ABOUT 1/4 TO ABOUT 4% OF THE ROSIN, BASED ON THE WEIGHT TO DRY PULP, IN SAID SUSPENSION, SAID TALL OIL ROSIN HAVING BEEN SUBJECTED TO TREATMENT WITH FROM ABOUT 1% TO ABOUT 4%, BASED ON THE WEIGHT OF TALL OIL ROSIN OF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF FORMALDEHYDE AND FORMALDEHYDE-YIELDING MATERIALS, AT A TEMPERATURE OF FROM ABOUT 100*C. TO ABOUT 200*C. IN THE PRESENCE OF AN ACID CATALYST PRIOR TO SAPONIFICATION WITH AQUEOUS ALKALI.
References Cited (Backward Citations)
US2084213A
Cited
US2197383A
Cited
US2684300A
Cited
US2712994A
Cited
US2720514A
Cited
US2744889A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-06-21 | 1963-12-21 | 1964-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-06-21 | 1967-12-21 | 1968-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-06-21 | 1971-12-21 | 1972-06-21 | $7700.00 | Window Closed / Lapsed |