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Patent US2617832A successfully refreshed from Google Patents.
US2617832A
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Method for preparing diphenylol methane
Assignee: General Electric Co
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Filing: 1951-06-28
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Granted: 1952-11-11
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Expires: 1971-06-28
Abstract
No abstract record available.
Inventors
- 👤 Robert W Martin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:37
CPC Classifications
C; C07; C07C; C07C37/00; C07C37/11; Y; Y10; Y10T; Y10T74/00; Y10T74/22
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
63 words
THE PROCESS WHICH COMPRISES EFFECTING REACTION BETWEEN A METHYLOL UREA SELECTED FROM THE CLASS CONSISTING OF MONOMETHYLOL UREA AND DIMETHYLOL UREA WITH PHENOL IN THE PRESENCE OF AN ACIDIC TYPE CATALYST, THE PHENOL BEING PRESENT IN A MOLAR RATIO OF AT LEAST 2.5 MOLS OF PHENOL PER MOL OF METHYLOL GROUP IN THE METHYLOL UREA, AND THEREAFTER ISOLATING THE DIPHENYLOL METHANE OBTAINED THEREBY.
Claim 2
Dependent Claim
63 words
THE PROCESS WHICH COMPRISES EFFECTING REACTION BETWEEN A METHYLOL UREA SELECTED FROM THE CLASS CONSISTING OF MONOMETHYLOL UREA AND DIMETHYLOL UREA WITH PHENOL IN THE PRESENCE OF AN ACIDIC TYPE CATALYST, THE PHENOL BEING PRESENT IN A MOLAR RATIO OF AT LEAST 2.5 MOLS OF PHENOL PER MOL OF METHYLOL GROUP IN THE METHYLOL UREA, AND THEREAFTER ISOLATING THE DIPHENYLOL METHANE OBTAINED THEREBY.
References Cited (Backward Citations)
DE511210C
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-11-11 | 1956-05-12 | 1956-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-11-11 | 1960-05-12 | 1960-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-11-11 | 1964-05-12 | 1964-11-11 | $7700.00 | Window Closed / Lapsed |