Patent US2668808A successfully refreshed from Google Patents.
US2668808A
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Process of preparing guanidineformaldehyde condensation products
Assignee: Arnold Hoffman & Co Inc
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Filing: 1951-12-13
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Granted: 1954-02-09
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Expires: 1971-12-13
Abstract
No abstract record available.
Inventors
- 👤 Charles A Robinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:17
CPC Classifications
C; C08; C08G; C08G12/00; C08G12/02; C08G12/04; C08G12/10; C08G12/14; D; D06; D06P; D06P1/00; D06P1/44; D06P1/52; D06P1/56
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
68 words
A PROCESS FOR PRODUCING GUANIDINE-FORMALDEHYDE CONDENSATION PRODUCTS FROM A GUANIDINE SALT CONTAINING AMMONIA IMPURITIES WHICH COMPRISES REACTING SAID SALT WITH A BASE STRONGER THAN GUANIDINE IN AT LEAST SUFFICIENT QUANTITY TO CONVERT SAID SALT TO FREE QUANIDINE AND SAID IMPURITIES TO AMMONIUM HYDROXIDE, AND REACTING SAID GUANIDINE WITH FORMALDEHYDE IN SUFFICIENT EXCESS TO BOTH FORM SAID CONDENSATION PRODUCT AND COMBINE WITH THE AMMONIUM HYDROXIDE IN SAID REACTION MIXTURE.
References Cited (Backward Citations)
US1780636A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-02-08 | 1957-08-10 | 1958-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-02-08 | 1961-08-10 | 1962-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-02-08 | 1965-08-10 | 1966-02-09 | $7700.00 | Window Closed / Lapsed |