Patent US2521950A successfully refreshed from Google Patents.
US2521950A
Expired / Lapsed
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Stabilized polyvinyl alkyl ethers
Assignee: GAF Chemicals Corp
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Filing: 1947-12-31
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Granted: 1950-09-12
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Expires: 1967-12-31
Abstract
No abstract record available.
Inventors
- 👤 Calvin E Schildknecht
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 05:29
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/16; C08K5/34; C08K5/35
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
69 words
A PROCESS OF PREPARING A STABILIZED POLYVINYL ALKYL ETHER OF IMPROVED COLOR WHICH COMPRISES INCORPORATING IN THE POLYMER FROM 0.2 TO 2% OF P-HYDROXY-N-PHENYLMORPHOLINE AND AN AMOUNT OF AN ALKALI SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL HYDROXIDES, CARBONATES AND BICARBONATES SUFFICIENT TO IMPART TO THE POLYMER AN ALKALINITY EQUAL TO A PH VALUE OF 9 TO 11.5 AS MEASUSED BY THE GLASS ELECTRODE IN A WATER-ALCOHOL MEDIUM.
Claim 2
Dependent Claim
69 words
A PROCESS OF PREPARING A STABILIZED POLYVINYL ALKYL ETHER OF IMPROVED COLOR WHICH COMPRISES INCORPORATING IN THE POLYMER FROM 0.2 TO 2% OF P-HYDROXY-N-PHENYLMORPHOLINE AND AN AMOUNT OF AN ALKALI SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL HYDROXIDES, CARBONATES AND BICARBONATES SUFFICIENT TO IMPART TO THE POLYMER AN ALKALINITY EQUAL TO A PH VALUE OF 9 TO 11.5 AS MEASUSED BY THE GLASS ELECTRODE IN A WATER-ALCOHOL MEDIUM.
References Cited (Backward Citations)
US2013941A
Cited
US2050843A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-09-11 | 1954-03-13 | 1954-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-09-11 | 1958-03-13 | 1958-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-09-11 | 1962-03-13 | 1962-09-12 | $7700.00 | Window Closed / Lapsed |