US2872425A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of preparing urea-formaldehyde molding composition
Assignee: Wyeth Holdings LLC
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Filing: 1955-04-15
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Granted: 1959-02-03
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Expires: 1975-04-15
Abstract
No abstract record available.
Inventors
- 👤 Alfred R Paz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 00:35
CPC Classifications
C; C08; C08L; C08L61/00; C08L61/20; C08L61/22; C08L61/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
189 words
A PROCESS FOR PREPARING A THERMOSETTING RESINOUS MOLDING COMPOSITION THAT COMPRISES BLENDING (A) A SUBSTANTIALLY UNALKYLATED AQUEOUS UREA-FORMALDEHYDE RESIN SYRUP PREPARED BY REACTING UREA AND FORMALDEHYDE IN A MOL RATIO OF FROM 1:1 TO 1:1.5, RESPECTIVELY, AT A PH OF FROM 6.0 TO 6.2 AND AT AN ELEVATED TEMPERATURE UNTIL THE FREE FORMALDEHYDE CONTENT DROPS TO LESS THAN 6.7% AND (B) A SUBSTANTIALLY UNALKYLATED AQUEOUS UREA-FORMALDEHYDE RESIN SYRUP PREPARED BY REACTING UREA AND FORMALDEHYDE IN A MOL RATIO OF FROM 1:1 TO 1:2.1, RESPECTIVELY AT REFLUX CONDITIONS AND AT A PH OF FROM 7.9 TO 8.2 UNTIL METHYLOL UREAS ARE FORMED, THEREAFTER ADJUSTING THE PH WITHIN THE ORDER OF 5.1 AND 5.4 AND CONTINUING THE REACTION AT REFLUX CONDITIONS UNTIL A VISCOSITY WITHIN THE ORDER OF 24 TO 44 CENTIPOISES IS OBTAINED AND FINALLY ADJUSTING THE PH TO WITHIN THE ORDER OF 7.7 TO 8.0, IN THE ORDER OF 80:20 TO 60:40 PARTS OF (A) TO PARTS OF (B), IMPREGNATING FROM ABOUT 15 TO 25 PARTS OF A FILLER WITH FROM ABOUT 85 TO 75 PARTS OF SAID BLEND, DRYING SAID RESIN IMPREGNATED FILLER AND COMMINUTING THE DRIED MATERIAL.
Claim 2
Dependent Claim
189 words
A PROCESS FOR PREPARING A THERMOSETTING RESINOUS MOLDING COMPOSITION THAT COMPRISES BLENDING (A) A SUBSTANTIALLY UNALKYLATED AQUEOUS UREA-FORMALDEHYDE RESIN SYRUP PREPARED BY REACTING UREA AND FORMALDEHYDE IN A MOL RATIO OF FROM 1:1 TO 1:1.5, RESPECTIVELY, AT A PH OF FROM 6.0 TO 6.2 AND AT AN ELEVATED TEMPERATURE UNTIL THE FREE FORMALDEHYDE CONTENT DROPS TO LESS THAN 6.7% AND (B) A SUBSTANTIALLY UNALKYLATED AQUEOUS UREA-FORMALDEHYDE RESIN SYRUP PREPARED BY REACTING UREA AND FORMALDEHYDE IN A MOL RATIO OF FROM 1:1 TO 1:2.1, RESPECTIVELY AT REFLUX CONDITIONS AND AT A PH OF FROM 7.9 TO 8.2 UNTIL METHYLOL UREAS ARE FORMED, THEREAFTER ADJUSTING THE PH WITHIN THE ORDER OF 5.1 AND 5.4 AND CONTINUING THE REACTION AT REFLUX CONDITIONS UNTIL A VISCOSITY WITHIN THE ORDER OF 24 TO 44 CENTIPOISES IS OBTAINED AND FINALLY ADJUSTING THE PH TO WITHIN THE ORDER OF 7.7 TO 8.0, IN THE ORDER OF 80:20 TO 60:40 PARTS OF (A) TO PARTS OF (B), IMPREGNATING FROM ABOUT 15 TO 25 PARTS OF A FILLER WITH FROM ABOUT 85 TO 75 PARTS OF SAID BLEND, DRYING SAID RESIN IMPREGNATED FILLER AND COMMINUTING THE DRIED MATERIAL.
References Cited (Backward Citations)
US2447621A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-02-02 | 1962-08-04 | 1963-02-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-02-02 | 1966-08-04 | 1967-02-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-02-02 | 1970-08-04 | 1971-02-03 | $7700.00 | Window Closed / Lapsed |