Patent US2877500A successfully refreshed from Google Patents.
US2877500A
Expired / Lapsed
US
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Process for preparing transparent polyethylene
Assignee: WR Grace and Co
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Filing: 1955-06-17
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Granted: 1959-03-17
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Expires: 1975-06-17
Abstract
No abstract record available.
Inventors
- 👤 William C Rainer
- 👤 Edward M Redding
- 👤 Joseph J Hitov
- 👤 Arthur W Sloan
- 👤 William D Stewart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:18
CPC Classifications
B; B29; B29C; B29C71/00; B29C71/04; B29K; B29K2023/00; B29K2023/04; B29K2023/06; B29K2995/00; B29K2995/0018; B29K2995/0026; Y; Y10; Y10S; Y10S383/00; Y10S383/908; Y10S8/00; Y10S8/09; Y10S8/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
60 words
A PROCESS COMPRISING IRRADIATING POLYETHYLENE AT A DOSAGE OF AT LEAST ABOUT 2X106 REP AT A TEMPERATURE BELOW ITS INITIAL SOFTENING POINT FOR A TIME SUFFICIENT TO SUBSTANTIALLY RAISE THE SOFTENING POINT AND THEN HOT STRETCHING IT IN AT LEAST ONE DIRECTION AT LEAST 100% AT AT TEMPERATURE NO LOWER THAN ABOUT 75*C. AND THEREAFTER COOLING THE HOT STRETCHED POLYETHYLENE.
Claim 2
Dependent Claim
60 words
A PROCESS COMPRISING IRRADIATING POLYETHYLENE AT A DOSAGE OF AT LEAST ABOUT 2X106 REP AT A TEMPERATURE BELOW ITS INITIAL SOFTENING POINT FOR A TIME SUFFICIENT TO SUBSTANTIALLY RAISE THE SOFTENING POINT AND THEN HOT STRETCHING IT IN AT LEAST ONE DIRECTION AT LEAST 100% AT AT TEMPERATURE NO LOWER THAN ABOUT 75*C. AND THEREAFTER COOLING THE HOT STRETCHED POLYETHYLENE.
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Cited
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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) | 1962-03-16 | 1962-09-15 | 1963-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-03-16 | 1966-09-15 | 1967-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-03-16 | 1970-09-15 | 1971-03-17 | $7700.00 | Window Closed / Lapsed |