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US3277224A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of thermoforming

Assignee: Poly-Pak Corp of America
•
Filing: 1963-04-05
•
Granted: 1966-10-04
•
Expires: 1983-04-05
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Abstract

No abstract record available.

Inventors

  • 👤 Carlton L Whiteford

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 14:56
CPC Classifications
B; B29; B29C; B29C51/00; B29C51/002; B29C55/00; B29C55/02; B29C55/10; B29C55/12; B29C55/14; B29C55/143; F; F02; F02M; F02M35/00; F02M35/02; F02M35/024; F02M35/02475; F02M35/02483; F02M35/12; F02M35/1205; F02M35/1255; F02M35/1266; F02M35/14

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 153 words
IN THE METHOD OF FABRICATING AN ARTICLE OF BIAXIALLY ORIENTED POLYSTYRENE FROM MONAXIALLY ORIENTED POLYSTYRENE SHEET MATERIAL, THE STEPS COMPRISING PROVIDING A ROLL OF POLYSTYRENE SHEET MATERIAL WHICH HAS BEEN PREORIENTED IN THE LONGITUDINAL DIRECTION AND IS SUBSTANTIALLY UNORIENTED IN THE TRANSVERSE DIRECTION SAID ROLL BEING AT A TEMPERATURE BELOW THE TEMPERATURE AT WHICH SAID SHEET MATERIAL WAS LONGITUDINALLY ORIENTED; UNCOILING AND SEVERING A GENERALLY RECTANGULAR LENGTH FROM SAID ROLL OF SHEET MATERIAL; INTRODUCING HEAT SUBSTANTIALLY UNIFORMLY INTO SAID LENGTH OF SHEET MATERIAL WHILE SUBSTANTIALLY PREVENTING LOSS OF ORIENTATION IN THE LONGITUDINAL DIRECTION; STRETCHING SAID HEATED LENGTH OF SHEET MATERIAL IN THE TRANSVERSE DIRECTION SUFFICIENTLY TO EFFECT SUBSTANTIAL MOLECULAR ORIENTATION IN THE TRANSVERSE DIRECTION AND THEREBY TO PRODUCE BIAXIAL ORIENTATION OF SAID LENGTH; AND THEREAFTER THERMOFORMING SAID BIAXIALLY ORIENTED LENGTH OF SHEET MATERIAL WHILE MAINTAINING A PORTION OF THE HEAT PROVIOUSLY INTRODUCTED THERINTO AND GRIPPING THE EDGES THEREOF TO PREVENT LOSS OF ORIENTATION.
Claim 2
Dependent Claim 153 words
IN THE METHOD OF FABRICATING AN ARTICLE OF BIAXIALLY ORIENTED POLYSTYRENE FROM MONAXIALLY ORIENTED POLYSTYRENE SHEET MATERIAL, THE STEPS COMPRISING PROVIDING A ROLL OF POLYSTYRENE SHEET MATERIAL WHICH HAS BEEN PREORIENTED IN THE LONGITUDINAL DIRECTION AND IS SUBSTANTIALLY UNORIENTED IN THE TRANSVERSE DIRECTION SAID ROLL BEING AT A TEMPERATURE BELOW THE TEMPERATURE AT WHICH SAID SHEET MATERIAL WAS LONGITUDINALLY ORIENTED; UNCOILING AND SEVERING A GENERALLY RECTANGULAR LENGTH FROM SAID ROLL OF SHEET MATERIAL; INTRODUCING HEAT SUBSTANTIALLY UNIFORMLY INTO SAID LENGTH OF SHEET MATERIAL WHILE SUBSTANTIALLY PREVENTING LOSS OF ORIENTATION IN THE LONGITUDINAL DIRECTION; STRETCHING SAID HEATED LENGTH OF SHEET MATERIAL IN THE TRANSVERSE DIRECTION SUFFICIENTLY TO EFFECT SUBSTANTIAL MOLECULAR ORIENTATION IN THE TRANSVERSE DIRECTION AND THEREBY TO PRODUCE BIAXIAL ORIENTATION OF SAID LENGTH; AND THEREAFTER THERMOFORMING SAID BIAXIALLY ORIENTED LENGTH OF SHEET MATERIAL WHILE MAINTAINING A PORTION OF THE HEAT PROVIOUSLY INTRODUCTED THERINTO AND GRIPPING THE EDGES THEREOF TO PREVENT LOSS OF ORIENTATION.

References Cited (Backward Citations)

US3025566A Cited
US3059810A Cited
US3082482A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1969-10-03 1970-04-04 1970-10-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1973-10-03 1974-04-04 1974-10-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1977-10-03 1978-04-04 1978-10-04 $7700.00 Window Closed / Lapsed

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