Patent US2556488A successfully refreshed from Google Patents.
US2556488A
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Manufacture of polystyrene
Assignee: Sherwin Williams Co
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Filing: 1945-10-22
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Granted: 1951-06-12
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Expires: 1965-10-22
Abstract
No abstract record available.
Inventors
- 👤 Wakeford Leslie Ernest
- 👤 Booth Ernest
- 👤 Buckle Richard Hartlebury
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:11
CPC Classifications
C; C22; C22B; C22B7/00; C22B7/02; B; B01; B01J; B01J23/00; B01J23/38; C08; C08F; C08F12/00; C08F12/02; C08F12/04; C08F12/06; C08F12/08; C08F16/00; C08F16/12; C08F212/00; C08F212/02; C08F212/04; C08F212/06; C08F212/08; C08F283/00; C08F283/01; C08G; C08G63/00; C08G63/02; C08G63/12; C08G63/46; C08G63/48; C08G67/00; C09; C09D; C09D125/00; C09D125/02; C09D125/04; C09D125/08; C09D125/14; C22B11/00; C22B11/02; C22B11/021; C22B11/026; C22B11/028; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
67 words
A PROCESS FOR THE PRODUCTION OF POLYSTYRENE OF A RELATIVELY LOW MOLECULAR WEIGHT IN THE ORDER OF 9,000 TO 12,000 WHICH CONSISTS IN EFFECTING THE POLYMERIZATION BY HEATING, IN THE ABSENCE OF A POLYMERIZATION CATALYST, MONOMERIC STYRENE IN A SOLVENT CONTAINING AT LEAST ONE TERPENE OF THE CLASS CONSISTING OF MONOCYCLIC AND DICYCLIC ALPHA TERPENES IN AN AMOUNT SUFFICIENT TO CONTROL THE MOLECULAR WEIGHT OF THE PRODUCT.
Claim 2
Dependent Claim
67 words
A PROCESS FOR THE PRODUCTION OF POLYSTYRENE OF A RELATIVELY LOW MOLECULAR WEIGHT IN THE ORDER OF 9,000 TO 12,000 WHICH CONSISTS IN EFFECTING THE POLYMERIZATION BY HEATING, IN THE ABSENCE OF A POLYMERIZATION CATALYST, MONOMERIC STYRENE IN A SOLVENT CONTAINING AT LEAST ONE TERPENE OF THE CLASS CONSISTING OF MONOCYCLIC AND DICYCLIC ALPHA TERPENES IN AN AMOUNT SUFFICIENT TO CONTROL THE MOLECULAR WEIGHT OF THE PRODUCT.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-06-11 | 1954-12-11 | 1955-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-06-11 | 1958-12-11 | 1959-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-06-11 | 1962-12-11 | 1963-06-12 | $7700.00 | Window Closed / Lapsed |