US2838801A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for making fire-resistant cellular vinyl aromatic polymer articles
Assignee: Dow Chemical Co
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Filing: 1957-03-29
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Granted: 1958-06-17
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Expires: 1977-03-29
Abstract
No abstract record available.
Inventors
- 👤 Long Chancey E De
- 👤 Wilson W Hunt
- 👤 Samuel G Ludington
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:26
CPC Classifications
C; C08; C08J; C08J11/00; C08J11/04; C08J11/06; C08J2325/00; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/62; Y10; Y10S; Y10S521/00; Y10S521/907
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
152 words
IN A CONTINUOUS PROCESS FOR MAKING A CELLULAR THERMOSPLASTIC ARTICLE WHEREIN A HEAT-PLASTIFIED THERMOPLASTIC VINYL AROMATIC POLYMER AT TEMPERATURES BETWEEN 120* AND 250* C. AND A NORMALLY GASEOUS AGENT CAPABLE OF BEING DISSOLVED BY THE POLYMER ARE FED INTO ADMIXTURE WITH ONE ANOTHER UNDER PRESSURE IN A MIXING AND COOLING ZONE IN AMOUNTS CORRESPONDING TO FORM 5 TO 25 PARTS BY WEIGHT OF THE NORMALLY GASEOUS AGENT PER 100 PARTS OF THE POLYMER AND WHEREIN THE INGREDIENTS ARE BLENDED INTO A UNIFORM MOBILE GEL UNDER PRESSURE AND COOLED TO A TEMPERATURE BETWEEN 60* AND C. IN SAID MIXING AND COOLING ZONE, AND THE GEL IS CONTIUOUSLY EXTRUDED INTO A ZONE OF LOWER PRESSURE SUFFICIENT TO EXPAND THE EXTRUDED MATERIAL WITH RESULTANT FORMATION OF A CELLULAR PLASTIC BODY WHICH IS CUT AND TRIMMED TO SHAPED ARTICLES, THEREBY PRODUCING AN APPRECIABLE PROPORTION OF SCRAP FOAM, THE STEPS WHICH CONSIST IN COLLECTING THE SCRAP FOAM,
Claim 2
Dependent Claim
152 words
IN A CONTINUOUS PROCESS FOR MAKING A CELLULAR THERMOSPLASTIC ARTICLE WHEREIN A HEAT-PLASTIFIED THERMOPLASTIC VINYL AROMATIC POLYMER AT TEMPERATURES BETWEEN 120* AND 250* C. AND A NORMALLY GASEOUS AGENT CAPABLE OF BEING DISSOLVED BY THE POLYMER ARE FED INTO ADMIXTURE WITH ONE ANOTHER UNDER PRESSURE IN A MIXING AND COOLING ZONE IN AMOUNTS CORRESPONDING TO FORM 5 TO 25 PARTS BY WEIGHT OF THE NORMALLY GASEOUS AGENT PER 100 PARTS OF THE POLYMER AND WHEREIN THE INGREDIENTS ARE BLENDED INTO A UNIFORM MOBILE GEL UNDER PRESSURE AND COOLED TO A TEMPERATURE BETWEEN 60* AND C. IN SAID MIXING AND COOLING ZONE, AND THE GEL IS CONTIUOUSLY EXTRUDED INTO A ZONE OF LOWER PRESSURE SUFFICIENT TO EXPAND THE EXTRUDED MATERIAL WITH RESULTANT FORMATION OF A CELLULAR PLASTIC BODY WHICH IS CUT AND TRIMMED TO SHAPED ARTICLES, THEREBY PRODUCING AN APPRECIABLE PROPORTION OF SCRAP FOAM, THE STEPS WHICH CONSIST IN COLLECTING THE SCRAP FOAM,
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) | 1961-06-16 | 1961-12-16 | 1962-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-06-16 | 1965-12-16 | 1966-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-06-16 | 1969-12-16 | 1970-06-17 | $7700.00 | Window Closed / Lapsed |