Patent US3019157A successfully refreshed from Google Patents.
US3019157A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Web-forming fibrous suspensions of improved freeness
Assignee: Wyeth Holdings LLC
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Filing: 1958-10-06
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Granted: 1962-01-30
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Expires: 1978-10-06
Abstract
No abstract record available.
Inventors
- 👤 Jr Walter F Reynolds
- 👤 Norman T Woodberry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 18:58
CPC Classifications
D; D21; D21H; D21H27/00; D21H27/06; C; C08; C08F; C08F20/00; C08F20/02; C08F20/52; C08F20/54; C08F20/56; C08F8/00; D21F; D21F1/00; D21H17/00; D21H17/20; D21H17/33; D21H17/34; D21H17/37; D21H17/375; D21H17/41; D21H17/42; D21H17/43
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
168 words
A PROCESS OF MANUFACTURING PAPER WHICH COMPRISES FORMING AN AQUEOUS SUSPENSION OF CELLULOSE PAPERMAKING FIBERS, ADDING THERETO BETWEEN ABOUT 0.5% AND 5% OF A WATER-SOLUBLE ALUMINUM METAL SALT BASED ON THE DRY WEIGHT OF FIBERS, THEREBY DECREASING THE PH OF THE SUSPENSION BELOW 5, ADDING SUFFICIENT OF A WATER-SOLUBLE ALKALI TO DECREASE THE ACIDITY OF THE SUSPENSION BY AT LEAST 0.1 OF A PH UNIT BUT INSUFFICIENT TO RAISE THE PH OF THE SUSPENSION ABOVE ABOUT 8, ADDING BETWEEN ABOUT 0.0001% AND 0.1% BASED ON THE DRY WEIGHT OF THE FIBERS OF A WATER-SOLUBLE ANIONIC LINEAR CARBON CHAIN POLYMER HAVING A MOLECULAR WEIGHT IN EXCESS OF 5 MILLION SUBSTANTIALLY COMPOSED OF CARBAMOYLALKYLENE AND CARBOXYALKYLENE LINKAGES CONTAINING NOT MORE THAN 4 CARBON ATOMS EACH, THE NUMBER OF CARBOXYALKYLENE LINKAGES BEING BETWEEN ABOUT 2% AND 15% OF THE TOTAL NUMBER OF CARBAMOYLAKYLENE AND CARBOXYALKYLENE LINKAGES, SHEETING SAID SUSPENSION ON A PAPERMAKING SCREEN TO FORM A WATERLAID WEB, DRAINING FREE WATER FROM SAID WEB, AND DRYING SAID WEB TO FORM PAPER.
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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) | 1965-01-29 | 1965-07-31 | 1966-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-01-29 | 1969-07-31 | 1970-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-01-29 | 1973-07-31 | 1974-01-30 | $7700.00 | Window Closed / Lapsed |