US2556898A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Urea-formaldehyde-sulphoxylate resin for high wet-strength paper
Assignee: Wyeth Holdings LLC
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Filing: 1946-12-16
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Granted: 1951-06-12
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Expires: 1966-12-16
Abstract
No abstract record available.
Inventors
- 👤 Brookes Alfred
- 👤 Hudson Frederick Lyth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 23:15
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/20; D21H17/33; D21H17/46; D21H17/47; D21H17/49; D21H17/50; C; C08; C08G; C08G12/00; C08G12/02; C08G12/40
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
25 words
PROCESS FOR THE MANUFACTURE FO RESINOUS CONDENSATION PRODUCTS OF UREA AND FORMALDEHYDE BY CONDENSING UREA AND FORMALDEHYDE TOGETHER IN THE PRESENCE OF A WATER-SOLUBLE SULPHOXYLATE.
Claim 2
Dependent Claim
25 words
PROCESS FOR THE MANUFACTURE FO RESINOUS CONDENSATION PRODUCTS OF UREA AND FORMALDEHYDE BY CONDENSING UREA AND FORMALDEHYDE TOGETHER IN THE PRESENCE OF A WATER-SOLUBLE SULPHOXYLATE.
Claim 3
Dependent Claim
34 words
HIGH WET STRENGTH PAPER SIZED WITH FROM 0.25 TO 25% BY WEIGHT OF A WATER-SOLUBLE SULPHOXYLATED CONDENSED CONDENSATION PRODUCT OF UREA AND FORMALDEHYDE IN THE RATIO OF 1 MOL UREA TO 1.5-3 MOLS FORMALDEHYDE.
Claim 4
Dependent Claim
34 words
HIGH WET STRENGTH PAPER SIZED WITH FROM 0.25 TO 25% BY WEIGHT OF A WATER-SOLUBLE SULPHOXYLATED CONDENSED CONDENSATION PRODUCT OF UREA AND FORMALDEHYDE IN THE RATIO OF 1 MOL UREA TO 1.5-3 MOLS FORMALDEHYDE.
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) | 1954-06-11 | 1954-12-11 | 1955-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-06-11 | 1958-12-11 | 1959-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-06-11 | 1962-12-11 | 1963-06-12 | $7700.00 | Window Closed / Lapsed |