Patent US2698787A successfully refreshed from Google Patents.
US2698787A
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Urea-formaldehyde resins for wet strength paper and their use
Assignee: Wyeth Holdings LLC
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Filing: 1951-12-17
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Granted: 1955-01-04
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Expires: 1971-12-17
Abstract
No abstract record available.
Inventors
- 👤 Arthur M Schiller
- 👤 Suen Tzeng Jiueg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:24
CPC Classifications
C; C08; C08G; C08G12/00; C08G12/02; C08G12/04; C08G12/10; C08G12/043; C08G12/046; C08G12/12; D; D21; D21H; D21H17/00; D21H17/20; D21H17/33; D21H17/46; D21H17/47; D21H17/49; D21H17/50
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
70 words
A PAPER SHEET OF IMPROVED WET STRENGTH COMPOSED OF WATERLAID CELLULOSIC FIBERS HAVING UNIFORMLY DISTRIBUTED ON THE FIBERS FROM 0.25% TO 5% BY DRY WEIGHT OF A WATERINSOLUBLE, THERMOCURED RESIN CURED, IN SITU, FROM A WATERSOLUBLE, CATIONIC RESINOUS CONDENSATION PRODUCT OF 1.8 TO 4.0 MOLS OF FORMALDEHYDE WITH 1 MOL OF UREA AND 0.02 TO 1 MOL OF A MONO-SUBSTITUTED UREA CONTAINING AN AMINOALKYL GROUP AND HAVING THE FOLLOWING FORMULA
References Cited (Backward Citations)
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US2338602A
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US2340046A
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US2559220A
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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) | 1958-01-03 | 1958-07-05 | 1959-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-01-03 | 1962-07-05 | 1963-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-01-03 | 1966-07-05 | 1967-01-04 | $7700.00 | Window Closed / Lapsed |