US2884386A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cyclic foaming method of making cellular plastic bodies
Assignee: Dow Chemical Co
•
Filing: 1956-09-24
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Granted: 1959-04-28
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Expires: 1976-09-24
Abstract
No abstract record available.
Inventors
- 👤 William J Mcmillan
- 👤 Keith R Denslow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:34
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/04; C08J9/12; C08J9/14; C08J9/143; C08J9/147; Y; Y10; Y10S; Y10S521/00; Y10S521/918
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
177 words
A METHOD FOR INCREASING THE FOAMED VOLUME OF A CLOSED CELL, FOAMED THERMOPLASTIC RESIN MASS OF THE GROUP CONSISTING OF STYRENE HOMOPOLYMERS AND COPOLYMERS, POLY (VINYLTOLUENE), POLYDICHLOROSTYRENE AND POLY(METHYL METHACRYLATE); WHICH CONTAINS IN ITS CELLS A GAS WHICH IS A NON-SOLVENT OR A POOR SOLVENT FOR SUCH RESIN WHICH METHOD CONSISTS IN HEATING SUCH FOAMED MASS TO A HEATSOFTENING TEMPERATURE FOR A TIME SUFFICIENT TO SOFTEN THE RESIN BUT BELOW A TEMPERATURE WHERE THE FOAM WOULD BE COLLAPSED OR THE RESIN WOULD BE DECOMPOSED TO EXPAND SUCH FOAMED MASS AND COOLING WHILE EXPOSING SAID HEAT EXPANDED MASS TO AN ATMOSPHERE OF A GAS WHICH HAS A PERMEABILITY RATE GREATER THAN THE PERMEABILITY RATE OF THE PRIMARY FOAMING GAS THROUGH THE CELL WALLS OF THE FOAMED MASS, AND REPEATING SAID CYCLES OF HEATING AND COOLING WHILE EXPOSING TO AN ATMOSPHERE OF SAID SECOND MORE PERMEABLE GAS A PLURALITY OF CYCLES WHEREBY THE VOLUME OF THE FOAMED MASS IS CONTINUALLY INCREASED TO A DESIRED VOLUME IN EXCESS OF THAT OBTAINABLE FROM THE HEAT EXPANSION OF THE PRIMARY GAS ALONE.
Claim 2
Independent Claim
177 words
A METHOD FOR INCREASING THE FOAMED VOLUME OF A CLOSED CELL, FOAMED THERMOPLASTIC RESIN MASS OF THE GROUP CONSISTING OF STYRENE HOMOPOLYMERS AND COPOLYMERS, POLY (VINYLTOLUENE), POLYDICHLOROSTYRENE AND POLY(METHYL METHACRYLATE); WHICH CONTAINS IN ITS CELLS A GAS WHICH IS A NON-SOLVENT OR A POOR SOLVENT FOR SUCH RESIN WHICH METHOD CONSISTS IN HEATING SUCH FOAMED MASS TO A HEATSOFTENING TEMPERATURE FOR A TIME SUFFICIENT TO SOFTEN THE RESIN BUT BELOW A TEMPERATURE WHERE THE FOAM WOULD BE COLLAPSED OR THE RESIN WOULD BE DECOMPOSED TO EXPAND SUCH FOAMED MASS AND COOLING WHILE EXPOSING SAID HEAT EXPANDED MASS TO AN ATMOSPHERE OF A GAS WHICH HAS A PERMEABILITY RATE GREATER THAN THE PERMEABILITY RATE OF THE PRIMARY FOAMING GAS THROUGH THE CELL WALLS OF THE FOAMED MASS, AND REPEATING SAID CYCLES OF HEATING AND COOLING WHILE EXPOSING TO AN ATMOSPHERE OF SAID SECOND MORE PERMEABLE GAS A PLURALITY OF CYCLES WHEREBY THE VOLUME OF THE FOAMED MASS IS CONTINUALLY INCREASED TO A DESIRED VOLUME IN EXCESS OF THAT OBTAINABLE FROM THE HEAT EXPANSION OF THE PRIMARY GAS ALONE.
References Cited (Backward Citations)
US2532242A
Cited
US2697255A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-04-27 | 1962-10-27 | 1963-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-04-27 | 1966-10-27 | 1967-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-04-27 | 1970-10-27 | 1971-04-28 | $7700.00 | Window Closed / Lapsed |