US3674740A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of producing polycarbonate
Assignee: Bayer AG
•
Filing: 1970-04-08
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Granted: 1972-07-04
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Expires: 1990-04-08
Abstract
Abstract For carrying out phase boundary surface reactions of components, e.g., production of polycarbonates from phosgene, Bisphenol A, sodium hydroxide and water a reaction tube is used, which comprises a series of residence time sections of relatively large internal tube diameter and alternately positions with respect to mixing sections of smaller internal tube diameter, the mixing sections providing Reynolds numbers greater than 2,000 for the reactants.
Inventors
- 👤 Hugo Vernaleken
- 👤 Otto Court
- 👤 Kurt Weirauch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 01:10
CPC Classifications
B; B01; B01J; B01J14/00; B01J19/00; B01J19/24; B01J19/2415; B01J19/242; C; C08; C08G; C08G64/00; C08G64/20; C08G64/205; B01J2219/00; B01J2219/00049; B01J2219/00164; B01J2219/00166
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
15 words
Process according to claim 1, the emulsions passing through the residence time sections without separation.
Claim 2
Dependent Claim
12 words
Process according to claim 1, said Reynolds number being greater than 2,300.
Claim 3
Dependent Claim
14 words
Process according to claIm 1, said material including methylene chloride, p-tert. butylphenol, and triethylamine.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-04 | 1976-01-03 | 1976-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-04 | 1980-01-03 | 1980-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-04 | 1984-01-03 | 1984-07-04 | $7700.00 | Window Closed / Lapsed |