US3280089A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Suspension polymerization of styrene in presence of hydroxyethyl cellulose and water-soluble chromate salt
Assignee: Atlantic Richfield Co
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Filing: 1963-12-05
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Granted: 1966-10-18
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Expires: 1983-12-05
Abstract
No abstract record available.
Inventors
- 👤 Harold A Wright
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:16
CPC Classifications
C; C08; C08F; C08F251/00; C08F251/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
69 words
A PROCESS COMPRISING POLYMERIZING STYRENE IN AQUEOUS SUSPENSION IN THE PRESENCE OF HYDROXYETHYL CELLULOSE AS THE SUSPENDING AGENT AND A FREE RADICAL GENERATING CATALYST AS THE INITIATOR, A SMALL AMOUNT OF WHICH IS PRESENT IN THE AQUEOUS PHASE, AND ADDING A WATER-SOLUBLE CHROMATE SALT OF ALKALI METAL, AMMONIUM, CALCIUM AND MAGNESIUM TO SAID POLYMERIZATION REACTION SYSTEM IN A RATIO OF HYDROXYETHYL CELLULOSE TO SALT, BY WEIGHT, OF FROM 10:1-100:1.
Claim 2
Dependent Claim
69 words
A PROCESS COMPRISING POLYMERIZING STYRENE IN AQUEOUS SUSPENSION IN THE PRESENCE OF HYDROXYETHYL CELLULOSE AS THE SUSPENDING AGENT AND A FREE RADICAL GENERATING CATALYST AS THE INITIATOR, A SMALL AMOUNT OF WHICH IS PRESENT IN THE AQUEOUS PHASE, AND ADDING A WATER-SOLUBLE CHROMATE SALT OF ALKALI METAL, AMMONIUM, CALCIUM AND MAGNESIUM TO SAID POLYMERIZATION REACTION SYSTEM IN A RATIO OF HYDROXYETHYL CELLULOSE TO SALT, BY WEIGHT, OF FROM 10:1-100:1.
References Cited (Backward Citations)
US2666047A
Cited
US2769788A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-10-17 | 1970-04-18 | 1970-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-10-17 | 1974-04-18 | 1974-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-10-17 | 1978-04-18 | 1978-10-18 | $7700.00 | Window Closed / Lapsed |