US2878168A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of polyvinyl acetate
Assignee: EIDP Inc
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Filing: 1955-12-21
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Granted: 1959-03-17
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Expires: 1975-12-21
Abstract
No abstract record available.
Inventors
- 👤 Walton B Tanner
- 👤 John R Wesel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:18
CPC Classifications
C; C08; C08F; C08F6/00; C08F6/001; C08F6/003; C08F6/06; C08F6/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
151 words
THE PROCESS FOR STRIPPING VINYL ACETATE FROM A SOLUTION COMPRISING POLYVINYL ACETATE, VINYL ACETATE AND SOLVENT FOR SAID POLUVINYL ACETATE SAID SOLVENT BOILING BELOW ABOUT 150* C., AND BEING SELECTED FROM TE GROUP CONSISTING OF METHYL ALCOHOL, ETHYL ALCOHOL, PROPYL ALCOHOLS AND SOLVENT ETHERS, ETHYL, HYDROCARBONS AND VINYL ACETATE, SAID PROCESS COMPRISING PASSING SAID SOLUTION BY GRAVITY FLOW DOWN A DISTILING COLUMN COUNTER TO UPWARDLY PASSING VAPOR OF UNPOLYMERIZABLE STRIPPING AGENT SELECTED FROM THE GROUP CONSISTING OF METHYL ALCOHOL, ETHYL ALCOHOL, PROPYL ALCOHOLS, ETHERS, ESTERS, AND HYDROCARBONS HAVING BOILING POINTS BELOW THE INTERNAL TEMPERATURE IN SAID DISTILLING COLUMN, REMOVING A SOLUTION OF POLYVINYL ACETATE FROM THE UPPER PART OF SAID THE LOWER PART OF SAID COLUMN, REMOVING A VAPOR MIXTURE CONTAINING VINLY ACETATE FROM TH UPPER PART OF SAID COLUMN AND MAINTAINING A PRESSURE BETWEEN ABOVE ABOUT ONE ATMOSPHERE AND BELOW ABOUT 14 ATMOSPHERES IN SAID COLUMN DURING SAID STRIPPING PROCESS.
Claim 2
Dependent Claim
151 words
THE PROCESS FOR STRIPPING VINYL ACETATE FROM A SOLUTION COMPRISING POLYVINYL ACETATE, VINYL ACETATE AND SOLVENT FOR SAID POLUVINYL ACETATE SAID SOLVENT BOILING BELOW ABOUT 150* C., AND BEING SELECTED FROM TE GROUP CONSISTING OF METHYL ALCOHOL, ETHYL ALCOHOL, PROPYL ALCOHOLS AND SOLVENT ETHERS, ETHYL, HYDROCARBONS AND VINYL ACETATE, SAID PROCESS COMPRISING PASSING SAID SOLUTION BY GRAVITY FLOW DOWN A DISTILING COLUMN COUNTER TO UPWARDLY PASSING VAPOR OF UNPOLYMERIZABLE STRIPPING AGENT SELECTED FROM THE GROUP CONSISTING OF METHYL ALCOHOL, ETHYL ALCOHOL, PROPYL ALCOHOLS, ETHERS, ESTERS, AND HYDROCARBONS HAVING BOILING POINTS BELOW THE INTERNAL TEMPERATURE IN SAID DISTILLING COLUMN, REMOVING A SOLUTION OF POLYVINYL ACETATE FROM THE UPPER PART OF SAID THE LOWER PART OF SAID COLUMN, REMOVING A VAPOR MIXTURE CONTAINING VINLY ACETATE FROM TH UPPER PART OF SAID COLUMN AND MAINTAINING A PRESSURE BETWEEN ABOVE ABOUT ONE ATMOSPHERE AND BELOW ABOUT 14 ATMOSPHERES IN SAID COLUMN DURING SAID STRIPPING PROCESS.
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) | 1962-03-16 | 1962-09-15 | 1963-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-03-16 | 1966-09-15 | 1967-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-03-16 | 1970-09-15 | 1971-03-17 | $7700.00 | Window Closed / Lapsed |