US2989503A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of powdered polycarbonates
Assignee: Onderzoekings Instituut Research
•
Filing: 1959-04-28
•
Granted: 1961-06-20
•
Expires: 1979-04-28
Abstract
No abstract record available.
Inventors
- 👤 Jibben Bart Paul
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:59
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/40; Y; Y10; Y10S; Y10S159/00; Y10S159/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
114 words
A PROCESS FOR THE PREPARATION OF POWDERED MACROMOLECULAR POLYCARBONATES COMPRISING THE STEPS OF REACTING 2,2-(4,4''-DIHYDROXYDIPHENYL)PROPANE WITH A COMPOUND OF THE GROUP CONSISTING OF PHOSGENE AND CHLOROCARBONIC ACID ESTERS OF 2,2-(4,4''-DIHYDROXYDIPHENYL)-PROPANE IN THE PRESENCE OF A COMPOUND OF THE GROUP CONSISTING OF DICHLOROMETHANE, TRICHLOROMETHANE AND MIXTURES THEREOF, OBTAINING THE POLYCARBONATE IN SOLUTION IN SAID COMPOUND, SAID POLYCARBONATE BEING PRESENT IN AN AMOUNT OF 20-40 GRAMS PER 100 GRAMS OF SAID COMPOUND, MIXING SAID SOLUTION WITH WATER AND AT LEAST 2 CC. OF DIMETHYLBENZENE PER GRAM OF POLYCARBONATE, SAID WATER BEING PRESENT IN AN AMOUNT OF 50 TO 300 CC. PER 100 CC. OF DIMETHYLBENZENE, AND EVAPORATING SAID MIXTURE TO OBTAIN THE POLYCARBONATE IN POWDER FORM.
Claim 2
Dependent Claim
114 words
A PROCESS FOR THE PREPARATION OF POWDERED MACROMOLECULAR POLYCARBONATES COMPRISING THE STEPS OF REACTING 2,2-(4,4''-DIHYDROXYDIPHENYL)PROPANE WITH A COMPOUND OF THE GROUP CONSISTING OF PHOSGENE AND CHLOROCARBONIC ACID ESTERS OF 2,2-(4,4''-DIHYDROXYDIPHENYL)-PROPANE IN THE PRESENCE OF A COMPOUND OF THE GROUP CONSISTING OF DICHLOROMETHANE, TRICHLOROMETHANE AND MIXTURES THEREOF, OBTAINING THE POLYCARBONATE IN SOLUTION IN SAID COMPOUND, SAID POLYCARBONATE BEING PRESENT IN AN AMOUNT OF 20-40 GRAMS PER 100 GRAMS OF SAID COMPOUND, MIXING SAID SOLUTION WITH WATER AND AT LEAST 2 CC. OF DIMETHYLBENZENE PER GRAM OF POLYCARBONATE, SAID WATER BEING PRESENT IN AN AMOUNT OF 50 TO 300 CC. PER 100 CC. OF DIMETHYLBENZENE, AND EVAPORATING SAID MIXTURE TO OBTAIN THE POLYCARBONATE IN POWDER FORM.
References Cited (Backward Citations)
CA578585A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-06-19 | 1964-12-19 | 1965-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-06-19 | 1968-12-19 | 1969-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-06-19 | 1972-12-19 | 1973-06-20 | $7700.00 | Window Closed / Lapsed |