Patent US3037050A successfully refreshed from Google Patents.
US3037050A
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Regeneration of terephthalic acid dimethyl ester from polyethylene terephthalate
Assignee: Glanzstoff AG
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Filing: 1960-02-25
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Granted: 1962-05-29
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Expires: 1980-02-25
Abstract
No abstract record available.
Inventors
- 👤 Heisenberg Erwin
- 👤 Siggel Erhard
- 👤 Lotz Rudolf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:30
CPC Classifications
C; C07; C07C; C07C69/00; C07C69/76; C07C69/80; C07C69/82; C07C67/00; C07C67/03
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
51 words
AN IMPROVED PROCESS FOR THE REGENERATION OF TEREPHTHALIC ACID DIMETHYL ESTER FROM POLYETHYLENE TEREPHTHALATE WHICH COMPRISES MELTING SAID POLYETHYLENE TEREPHTHALATE IN AN INERT ATMOSPHERE, AND CONTACTING THE MOLTEN POLYETHYLENE TEREPHTHALATE AT SUBSTANTIALLY ATMOSPHERIC PRESSURE IN THE PRESENCE OF AN ESTERIFICATION CATALYST WITH METHANOL VAPOR HEATED TO FROM ABOUT 65*C. TO 300*C.
Claim 2
Dependent Claim
51 words
AN IMPROVED PROCESS FOR THE REGENERATION OF TEREPHTHALIC ACID DIMETHYL ESTER FROM POLYETHYLENE TEREPHTHALATE WHICH COMPRISES MELTING SAID POLYETHYLENE TEREPHTHALATE IN AN INERT ATMOSPHERE, AND CONTACTING THE MOLTEN POLYETHYLENE TEREPHTHALATE AT SUBSTANTIALLY ATMOSPHERIC PRESSURE IN THE PRESENCE OF AN ESTERIFICATION CATALYST WITH METHANOL VAPOR HEATED TO FROM ABOUT 65*C. TO 300*C.
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) | 1965-05-28 | 1965-11-27 | 1966-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-05-28 | 1969-11-27 | 1970-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-05-28 | 1973-11-27 | 1974-05-29 | $7700.00 | Window Closed / Lapsed |