US3137745A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming hollow plastic articles
Assignee: Hercules Powder Co
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Filing: 1962-10-15
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Granted: 1964-06-16
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Expires: 1982-10-15
Abstract
No abstract record available.
Inventors
- 👤 Paul L Johnstone
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:19
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/16; C08J9/0014; C08J9/0028; C08J2323/00; C08J2323/02; C08J2323/10; C08J2323/12; Y; Y10; Y10S; Y10S264/00; Y10S264/01; Y10S264/08; Y10S264/13; Y10S264/16; Y10S264/18; Y10S8/00; Y10S8/09
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
64 words
THE PROCESS OF PRODUCING HOLLOW ARTICLES OF POLYPROPYLENE FOAM WHICH COMPRISES EXTRUDING A MIXTURE OF A STEREOREGULAR POLYPROPYLENE, A BLOWING AGENT, AND AN AZIDO CROSS-LINKING AGENT, AT A TEMPERATURE ABOVE THE SOFTENING TEMPERATURE OF THE MIXTURE AND SUFFICIENT TO RELEASE THE GAS FROM THE BLOWING AGENT AND TO EFFECT CROSSLINKING OF THE POLYPROPYLENE, INTO A PARISON AND BLOWING SAID PARISON INTO A HOLLOW MOLD.
Claim 2
Dependent Claim
64 words
THE PROCESS OF PRODUCING HOLLOW ARTICLES OF POLYPROPYLENE FOAM WHICH COMPRISES EXTRUDING A MIXTURE OF A STEREOREGULAR POLYPROPYLENE, A BLOWING AGENT, AND AN AZIDO CROSS-LINKING AGENT, AT A TEMPERATURE ABOVE THE SOFTENING TEMPERATURE OF THE MIXTURE AND SUFFICIENT TO RELEASE THE GAS FROM THE BLOWING AGENT AND TO EFFECT CROSSLINKING OF THE POLYPROPYLENE, INTO A PARISON AND BLOWING SAID PARISON INTO A HOLLOW MOLD.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-06-16 | 1967-12-16 | 1968-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-06-16 | 1971-12-16 | 1972-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-06-16 | 1975-12-16 | 1976-06-16 | $7700.00 | Window Closed / Lapsed |