US2688774A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for molding polystyrenes
Assignee: Monsanto Chemicals Ltd
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Filing: 1951-04-25
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Granted: 1954-09-14
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Expires: 1971-04-25
Abstract
No abstract record available.
Inventors
- 👤 Theodore P Malinowski
- 👤 Charles G Trudeau
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:36
CPC Classifications
B; B29; B29C; B29C70/00; B29C70/04; B29C70/28; Y; Y10; Y10S; Y10S138/00; Y10S138/02; Y10S264/00; Y10S264/53; Y10T; Y10T442/00; Y10T442/20; Y10T442/2361
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
92 words
A PROCESS FOR PRODUCING MOLDED OBJECTS OF GLASS-FILLED POLYSTYRENE HAVING IMPROVED IMPACT STRENGTH WHICH COMPRISES INCORPORATING 100 PARTS OF GLASS FIBERS INTO 230 AND 450 PARTS OF POLYSTYRENE IN THE SUBSTANTIAL ABSENCE OF MECHANICAL WORKING, COMPRESSING THE FILLED POLYSTYRENE AT A PRESSURE OF AT LEAST 1000 P. S. I. AT A TEMPERATURE OF AT LEAST 125* C. IN THE SUBSTANTIAL ABSENCE OF MECHANICAL WORKING AND THEREAFTER INJECTION MOLDING THE COMPRESSED POLYSTYRENE AT A TEMPERATURE OF FROM 145* C. TO 350* C. AND A PRESSURE OF FROM 8000 TO 40,000 P. S. I.
Claim 2
Dependent Claim
92 words
A PROCESS FOR PRODUCING MOLDED OBJECTS OF GLASS-FILLED POLYSTYRENE HAVING IMPROVED IMPACT STRENGTH WHICH COMPRISES INCORPORATING 100 PARTS OF GLASS FIBERS INTO 230 AND 450 PARTS OF POLYSTYRENE IN THE SUBSTANTIAL ABSENCE OF MECHANICAL WORKING, COMPRESSING THE FILLED POLYSTYRENE AT A PRESSURE OF AT LEAST 1000 P. S. I. AT A TEMPERATURE OF AT LEAST 125* C. IN THE SUBSTANTIAL ABSENCE OF MECHANICAL WORKING AND THEREAFTER INJECTION MOLDING THE COMPRESSED POLYSTYRENE AT A TEMPERATURE OF FROM 145* C. TO 350* C. AND A PRESSURE OF FROM 8000 TO 40,000 P. S. I.
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) | 1957-09-13 | 1958-03-15 | 1958-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-09-13 | 1962-03-15 | 1962-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-09-13 | 1966-03-15 | 1966-09-14 | $7700.00 | Window Closed / Lapsed |