US3095429A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of crystalline diglycidyl ether of bisphenol a
Assignee: Dow Chemical Co
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Filing: 1959-05-19
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Granted: 1963-06-25
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Expires: 1979-05-19
Abstract
No abstract record available.
Inventors
- 👤 John C Smith
- 👤 William R Bradshaw
- 👤 Lionel M Raff
- 👤 Wilbur L Bressler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 07:45
CPC Classifications
C; C07; C07D; C07D303/00; C07D303/02; C07D303/12; C07D303/18; C07D303/20; C07D303/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
114 words
A PROCESS FOR MAKING MONOMERIC DIGLYCIDYL ETHER OF BISPHENOL A HAVING A MELTING POINT OF AT LEAST ABOUT 39*C. AND AN EPOXY CONTENT OF AT LEAST ABOUT 24.45 COMPRISING THE STEPS OF DISSOLVING CRUDE DIGLYCIDYL ETHER OF BISPHENOL A HAVING A MELTING POINT BELOW ABOUT 39* C. AND AN EPOXY CONTENT BELOW ABOUT 24.4% IN A LOWER ALKANOL, COOLING THE RESULTING SOLUTION UNTIL A SUBSTANTIAL PORTION OF THE ETHER SEPARATED IN LIQUID FORM FROM THE SOLUTION, SEPARATING THIS PORTION FROM THE SOLUTION REDISSOLVING SAID PORTION IN FRESH SOLVENT, COOLING THE THUS FORMED SECOND SOLUTION UNTIL CRYSTALS OF MONOMERIC DIGLYCIDLY ETHER OF BISPHENOL A ARE FORMED AND SEPARATING SAID CRYSTALS FROM THE SAID SECOND SOLUTION.
Claim 2
Dependent Claim
114 words
A PROCESS FOR MAKING MONOMERIC DIGLYCIDYL ETHER OF BISPHENOL A HAVING A MELTING POINT OF AT LEAST ABOUT 39*C. AND AN EPOXY CONTENT OF AT LEAST ABOUT 24.45 COMPRISING THE STEPS OF DISSOLVING CRUDE DIGLYCIDYL ETHER OF BISPHENOL A HAVING A MELTING POINT BELOW ABOUT 39* C. AND AN EPOXY CONTENT BELOW ABOUT 24.4% IN A LOWER ALKANOL, COOLING THE RESULTING SOLUTION UNTIL A SUBSTANTIAL PORTION OF THE ETHER SEPARATED IN LIQUID FORM FROM THE SOLUTION, SEPARATING THIS PORTION FROM THE SOLUTION REDISSOLVING SAID PORTION IN FRESH SOLVENT, COOLING THE THUS FORMED SECOND SOLUTION UNTIL CRYSTALS OF MONOMERIC DIGLYCIDLY ETHER OF BISPHENOL A ARE FORMED AND SEPARATING SAID CRYSTALS FROM THE SAID SECOND SOLUTION.
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) | 1966-06-24 | 1966-12-24 | 1967-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-06-24 | 1970-12-24 | 1971-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-06-24 | 1974-12-24 | 1975-06-25 | $7700.00 | Window Closed / Lapsed |