Patent US4249429A successfully refreshed from Google Patents.
US2559221A
Expired / Lapsed
US
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Manufacture of wet strength paper
Assignee: Wyeth Holdings LLC
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Filing: 1947-06-28
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Granted: 1951-07-03
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Expires: 1967-06-28
Abstract
No abstract record available.
Inventors
- 👤 Charles S Maxwell
- 👤 Chester G Landes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:19
CPC Classifications
C; C08; C08G; C08G12/00; C08G12/02; C08G12/26; C08G12/30; C08G12/32; D; D06; D06M; D06M15/00; D06M15/19; D06M15/37; D06M15/39; D06M15/423; D21; D21H; D21H17/00; D21H17/20; D21H17/33; D21H17/46; D21H17/47; D21H17/49; D21H17/51; D21H17/63; D21H17/66; D21H21/00; D21H21/14; D21H21/18; D21H21/20; D21H23/00; D21H23/76; D21H23/765
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
65 words
A METHOD FOR THE PRODUCTION OF PAPER OF IMPROVED WET STRENGTH WHICH COMPRISES PREPARING A SUSPENSION OF CELLULOSIC FIBERS IN WATER CONTAINING FROM ABOUT 50 TO ABOUT 150 PARTS PER MILLION OF DISSOLVED SULFATE ION, ADDING TO SAID SUSPENSION A COLLOIDAL SOLUTION OF CATIONIC MELAMINEFORMALDEHYDE RESIN, ADSORBING SUBSTANTIAL QUANTITIES OF SAID RESIN ON THE CELLULOSIC FIBERS, FORMING THE TREATED FIBERS INTO PAPER, AND HEATING THE
Claim 2
Independent Claim
65 words
A METHOD FOR THE PRODUCTION OF PAPER OF IMPROVED WET STRENGTH WHICH COMPRISES PREPARING A SUSPENSION OF CELLULOSIC FIBERS IN WATER CONTAINING FROM ABOUT 50 TO ABOUT 150 PARTS PER MILLION OF DISSOLVED SULFATE ION, ADDING TO SAID SUSPENSION A COLLOIDAL SOLUTION OF CATIONIC MELAMINEFORMALDEHYDE RESIN, ADSORBING SUBSTANTIAL QUANTITIES OF SAID RESIN ON THE CELLULOSIC FIBERS, FORMING THE TREATED FIBERS INTO PAPER, AND HEATING THE
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-07-02 | 1955-01-01 | 1955-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-07-02 | 1959-01-01 | 1959-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-07-02 | 1963-01-01 | 1963-07-03 | $7700.00 | Window Closed / Lapsed |