Patent US3207790A successfully refreshed from Google Patents.
US3207790A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for reducing the color of discolored alkanolamines
Assignee: Dow Chemical Co
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Filing: 1961-07-06
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Granted: 1965-09-21
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Expires: 1981-07-06
Abstract
No abstract record available.
Inventors
- 👤 Glew David Neville
- 👤 Young David Matheson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 11:04
CPC Classifications
C; C07; C07C; C07C215/00; C07C215/02; C07C215/04; C07C215/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
39 words
A PROCESS FOR IMPROVING THE COLOR OF ALKANOLAMINES THAT DEVELOP UNDESIRABLE COLOR ON AGING SAID PROCESS COMPRISING ADDING TO SAID ALKANOLAMINE A QUANTITY, SUFFICIENT TO SUBSTANTIALLY REDUCE THE COLOR OF THE ALKANOLAMINE, OF A BOROHYDRIDE OF AN ALKALI METAL.
Claim 2
Dependent Claim
39 words
A PROCESS FOR IMPROVING THE COLOR OF ALKANOLAMINES THAT DEVELOP UNDESIRABLE COLOR ON AGING SAID PROCESS COMPRISING ADDING TO SAID ALKANOLAMINE A QUANTITY, SUFFICIENT TO SUBSTANTIALLY REDUCE THE COLOR OF THE ALKANOLAMINE, OF A BOROHYDRIDE OF AN ALKALI METAL.
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) | 1968-09-20 | 1969-03-22 | 1969-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-09-20 | 1973-03-22 | 1973-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-09-20 | 1977-03-22 | 1977-09-21 | $7700.00 | Window Closed / Lapsed |