US3019488A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for vacuum molding polymer sheets
Assignee: Phillips Petroleum Co
•
Filing: 1958-06-16
•
Granted: 1962-02-06
•
Expires: 1978-06-16
Abstract
No abstract record available.
Inventors
- 👤 Doyle Robert
- 👤 William L Holt
- 👤 Wayne E Cooper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:00
CPC Classifications
B; B29; B29C; B29C51/00; B29C51/002; B29C33/00; B29C33/02; B29C33/04; B29C51/10; B29C51/26; B29C51/30; B29C51/32; B29C51/42; B29C51/426; B29C51/428
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
92 words
IN A PROCESS IN WHICH A SHEET OF A POLYMER HAVING A DENSITY OF AT LEAST 0.90 AT 25* C. AND A CRYSTALLINITY OF AT LEAST 80 PERCENT AT 25* C. IS FORMED INTO A MOLDED ARTICLE BY HEATING THE SHEET AND THEREAFTER PULLING THE SHEET AROUND A MOLD BY EVACUATING AIR FROM BETWEEN THE MOLD AND SHEET, THE IMPROVEMENT WHICH COMPRISES CONTROLLING THE TEMPERATURE OF SAID MOLD SO THAT ITS SURFACE TEMPERATURE IS IN THE RANGE OF ABOUT 150 TO ABOUT 230* F. WHEN SAID SHEET INITIALLY CONTACTS SAID MOLD SURFACE.
Claim 2
Dependent Claim
92 words
IN A PROCESS IN WHICH A SHEET OF A POLYMER HAVING A DENSITY OF AT LEAST 0.90 AT 25* C. AND A CRYSTALLINITY OF AT LEAST 80 PERCENT AT 25* C. IS FORMED INTO A MOLDED ARTICLE BY HEATING THE SHEET AND THEREAFTER PULLING THE SHEET AROUND A MOLD BY EVACUATING AIR FROM BETWEEN THE MOLD AND SHEET, THE IMPROVEMENT WHICH COMPRISES CONTROLLING THE TEMPERATURE OF SAID MOLD SO THAT ITS SURFACE TEMPERATURE IS IN THE RANGE OF ABOUT 150 TO ABOUT 230* F. WHEN SAID SHEET INITIALLY CONTACTS SAID MOLD SURFACE.
References Cited (Backward Citations)
US2531539A
Cited
US2580883A
Cited
US2660761A
Cited
US2694227A
Cited
US2781078A
Cited
GB808389A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-02-05 | 1965-08-07 | 1966-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-02-05 | 1969-08-07 | 1970-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-02-05 | 1973-08-07 | 1974-02-06 | $7700.00 | Window Closed / Lapsed |