Patent US3294741A successfully refreshed from Google Patents.
US3294741A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making polycarbonate particles
Assignee: Bayer AG
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Filing: 1960-04-20
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Granted: 1966-12-27
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Expires: 1980-04-20
Abstract
No abstract record available.
Inventors
- 👤 Schnell Hermann
- 👤 Fritsch Karl Herbert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 12:03
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/20; C08G64/26; C08G64/28; C08G64/22; C08G64/24; C08G64/40; Y; Y10; Y10S; Y10S159/00; Y10S159/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
109 words
A METHOD FOR MAKING A POLYCARBONATE RESIN IN PARTICULATE FROM WHICH COMPRISES IN ON STEP REACTING A DI-(MONOHYDROXY ARYL) ALKANE WITH A MEMBER SELECTED FROM THE GROUP CONSISTING OF PHOSGENE AND A CHLOROCARBONIC ACID ESTER IN A TWO-PHASE SYSTEM WITH THE DI-(MONOHYDROXY ARYL) ALKANE IN AN ALKALINE AQUEOUS PHASE AND THE RESULTING POLYCARBONATE IN AN INERT ORGANIC SOLVENT THEREFOR, SAID POLYCARBONATE SOLUTION BEING SUBSTANTIALLY IMMISCIBLE WITH SAID AQUEOUS PHASE, AGITATING THE TWOPHASE SYSTEM TO SUSPEND GLOBULES OF THE POLYCARBONATE SOLUTION IN THE AQUEOUS PHASE WHILE SIMULTANEOUSLY REMOVING THE SOLVENT FROM THE GLOBULES TO FORM PARTICLES OF POLYCARBONATE HAVING A DIAMETER OF FROM ABOUT 10 MICRONS TO ABOUT 2,000 MICRONS.
Claim 2
Independent Claim
109 words
A METHOD FOR MAKING A POLYCARBONATE RESIN IN PARTICULATE FROM WHICH COMPRISES IN ON STEP REACTING A DI-(MONOHYDROXY ARYL) ALKANE WITH A MEMBER SELECTED FROM THE GROUP CONSISTING OF PHOSGENE AND A CHLOROCARBONIC ACID ESTER IN A TWO-PHASE SYSTEM WITH THE DI-(MONOHYDROXY ARYL) ALKANE IN AN ALKALINE AQUEOUS PHASE AND THE RESULTING POLYCARBONATE IN AN INERT ORGANIC SOLVENT THEREFOR, SAID POLYCARBONATE SOLUTION BEING SUBSTANTIALLY IMMISCIBLE WITH SAID AQUEOUS PHASE, AGITATING THE TWOPHASE SYSTEM TO SUSPEND GLOBULES OF THE POLYCARBONATE SOLUTION IN THE AQUEOUS PHASE WHILE SIMULTANEOUSLY REMOVING THE SOLVENT FROM THE GLOBULES TO FORM PARTICLES OF POLYCARBONATE HAVING A DIAMETER OF FROM ABOUT 10 MICRONS TO ABOUT 2,000 MICRONS.
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) | 1969-12-26 | 1970-06-27 | 1970-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-12-26 | 1974-06-27 | 1974-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-12-26 | 1978-06-27 | 1978-12-27 | $7700.00 | Window Closed / Lapsed |