US2640816A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of solutions of polyvinyl alcohol-acetate
Assignee: Shawinigan Chemicals Ltd
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Filing: 1952-05-03
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Granted: 1953-06-02
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Expires: 1972-05-03
Abstract
No abstract record available.
Inventors
- 👤 Leo M Germain
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:50
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/12; C08J; C08J5/00; C08J5/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
72 words
A PROCESS FOR THE PREPARATION OF A SOLUTION OF POLYVINYL ALCOHOL-ACETATE RESIN, SAID RESIN CONTAINING AT LEAST 45% BY WEIGHT OF POLYVINYL ACETATE COMPRISING THE REACTION, IN SOLUTION, OF POLYVINYL ACETATE WITH METHANOL IN THE PRESENCE OF EXCESS METHANOL, AN ALKALINE ALCOHOLYSIS CATALYST NOT EXCEEDING 15% OF THE STOICHIOMETRIC EQUIVALENT OF THE ORIGINAL POLYVINYL ACETATE, AND WATER IN AN AMOUNT BETWEEN 12% AND 20% BY WEIGHT OF ALL THE METHANOL AND WATER.
Claim 2
Dependent Claim
72 words
A PROCESS FOR THE PREPARATION OF A SOLUTION OF POLYVINYL ALCOHOL-ACETATE RESIN, SAID RESIN CONTAINING AT LEAST 45% BY WEIGHT OF POLYVINYL ACETATE COMPRISING THE REACTION, IN SOLUTION, OF POLYVINYL ACETATE WITH METHANOL IN THE PRESENCE OF EXCESS METHANOL, AN ALKALINE ALCOHOLYSIS CATALYST NOT EXCEEDING 15% OF THE STOICHIOMETRIC EQUIVALENT OF THE ORIGINAL POLYVINYL ACETATE, AND WATER IN AN AMOUNT BETWEEN 12% AND 20% BY WEIGHT OF ALL THE METHANOL AND WATER.
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) | 1956-06-01 | 1956-12-01 | 1957-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-06-01 | 1960-12-01 | 1961-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-06-01 | 1964-12-01 | 1965-06-02 | $7700.00 | Window Closed / Lapsed |