Patent US2527495A successfully refreshed from Google Patents.
US2527495A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyvinyl acetal resin
Assignee: Shawinigan Resins Corp
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Filing: 1947-12-31
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Granted: 1950-10-24
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Expires: 1967-12-31
Abstract
No abstract record available.
Inventors
- 👤 Andrew F Fitzhugh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:01
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/28; C08J; C08J5/00; C08J5/18; C08F2810/00; C08F2810/30
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
69 words
A PROCESS FOR PRODUCING AN ORGANIC SOLVENT SOLUBLE POLYVINYL ACETAL RESIN FROM CROTONALDEHYDE WHICH COMPRISES REACTING A MIXTURE OF POLYVINYL ALCOHOL AND AT LEAST THREE MOLECULAR EQUIVALENTS OF CROTONALDEHYDE FOR EACH MOLECULAR EQUIVALENT OF POLYVINYL ALCOHOL, IN THE PRESENCE OF SULFURIC ACID AND A SOLVENT CONTAINING AT LEAST 75% METHANOL, SAID SOLVENT BEING PRESENT IN AN AMOUNT OF 600 TO 2000 PARTS FOR EVERY 100 PARTS OF POLYVINYL ALCOHOL.
Claim 2
Dependent Claim
69 words
A PROCESS FOR PRODUCING AN ORGANIC SOLVENT SOLUBLE POLYVINYL ACETAL RESIN FROM CROTONALDEHYDE WHICH COMPRISES REACTING A MIXTURE OF POLYVINYL ALCOHOL AND AT LEAST THREE MOLECULAR EQUIVALENTS OF CROTONALDEHYDE FOR EACH MOLECULAR EQUIVALENT OF POLYVINYL ALCOHOL, IN THE PRESENCE OF SULFURIC ACID AND A SOLVENT CONTAINING AT LEAST 75% METHANOL, SAID SOLVENT BEING PRESENT IN AN AMOUNT OF 600 TO 2000 PARTS FOR EVERY 100 PARTS OF POLYVINYL ALCOHOL.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-10-23 | 1954-04-24 | 1954-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-10-23 | 1958-04-24 | 1958-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-10-23 | 1962-04-24 | 1962-10-24 | $7700.00 | Window Closed / Lapsed |