US3379703A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing polyvinyl alcohol in the presence of dialdehydes
Assignee: Hoechst AG
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Filing: 1964-12-15
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Granted: 1968-04-23
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Expires: 1984-12-15
Abstract
No abstract record available.
Inventors
- 👤 Ehmann Werner
- 👤 Sommer Siegfried
- 👤 Winkler Fritz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:31
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
91 words
IN A PROCESS FOR THE PRODUCTION OF POLYVINYL ALCOHOL BY ACID HYDROLYSIS OF A POLYMERIC POLYVINYL ESTER WHEREIN THE ACID MOIETY IS DERIVED FROM A SATURATED MONOCARBOXYLIC ACID HAVING 1 TO 18 CARBON ATOMS, THE IMPROVEMENT WHICH COMPRISES CARRYING OUT THE HYDROLYSIS IN THE PRESLENCE OF 0.01 TO 0.3%, CALCULATED ON THE WEIGHT OF SAID POLYMER, OF A DIALDERHYDE THE ALDEHYDE GROUPS OF WHICH ARE SEPARATED BY AT LEAST ONE CARBON ATOM SELECTED FROM THE GROUP CONSISTING OF SATURATED HYDROCARBON, AROMATIC OR ALICYCLIC DIALS HAVING FROM 3 TO 14 CARBON ATOMS.
Claim 2
Dependent Claim
91 words
IN A PROCESS FOR THE PRODUCTION OF POLYVINYL ALCOHOL BY ACID HYDROLYSIS OF A POLYMERIC POLYVINYL ESTER WHEREIN THE ACID MOIETY IS DERIVED FROM A SATURATED MONOCARBOXYLIC ACID HAVING 1 TO 18 CARBON ATOMS, THE IMPROVEMENT WHICH COMPRISES CARRYING OUT THE HYDROLYSIS IN THE PRESLENCE OF 0.01 TO 0.3%, CALCULATED ON THE WEIGHT OF SAID POLYMER, OF A DIALDERHYDE THE ALDEHYDE GROUPS OF WHICH ARE SEPARATED BY AT LEAST ONE CARBON ATOM SELECTED FROM THE GROUP CONSISTING OF SATURATED HYDROCARBON, AROMATIC OR ALICYCLIC DIALS HAVING FROM 3 TO 14 CARBON ATOMS.
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) | 1971-04-23 | 1971-10-23 | 1972-04-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-04-23 | 1975-10-23 | 1976-04-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-04-23 | 1979-10-23 | 1980-04-23 | $7700.00 | Window Closed / Lapsed |