Patent US4270992A successfully refreshed from Google Patents.
US4270992A
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Process for producing glycol
Assignee: Tosoh Corp
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Filing: 1980-05-08
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Granted: 1981-06-02
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Expires: 2000-05-08
Abstract
Abstract Ethyleneglycol or a mixture of ethyleneglycol and propyleneglycol is produced by an electrolysis of formaldehyde in an alkaline solution by using a carbon type electrode as a cathode.
Inventors
- 👤 Mitsutaka Saito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:27
CPC Classifications
C; C25; C25B; C25B3/00; C25B3/20; C25B3/29; C25B3/295; C25B3/01; C25B3/07
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
34 words
In a process for producing a glycol from formaldehyde, an improvement characterized in that the electrolysis of formaldehyde is carried out in an alkaline solution by using a carbon type electrode as a cathode.
Claim 2
Dependent Claim
34 words
In a process for producing a glycol from formaldehyde, an improvement characterized in that the electrolysis of formaldehyde is carried out in an alkaline solution by using a carbon type electrode as a cathode.
Claim 3
Dependent Claim
30 words
The process for producing a glycol according to claim 1 wherein an alkali metal hydroxide, an alkali metal carbonate, an alkali metal phosphate or ammonia is used as an electrolyte.
Claim 4
Dependent Claim
27 words
The process for producing a glycol according to claim 2, wherein ethyleneglycol and propyleneglycol are produced by using potassium hydroxide or a potassium salt as the electrolyte.
Claim 5
Dependent Claim
25 words
The process for producing a glycol according to claim 2 wherein ethyleneglycol is produced by using sodium hydroxide or a sodium salt as the electrolyte.
References Cited (Backward Citations)
US3899401A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-06-01 | 1984-12-01 | 1985-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-01 | 1988-12-01 | 1989-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-01 | 1992-12-01 | 1993-06-02 | $7700.00 | Window Closed / Lapsed |