Patent US2981724A successfully refreshed from Google Patents.
US2981724A
Expired / Lapsed
US
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Suspension polymerization of vinyl chloride
Assignee: Escambia Chemical Corp
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Filing: 1957-05-06
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Granted: 1961-04-25
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Expires: 1977-05-06
Abstract
No abstract record available.
Inventors
- 👤 Robert S Holdsworth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:05
CPC Classifications
C; C08; C08F; C08F14/00; C08F14/02; C08F14/04; C08F14/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
112 words
THE PROCESS OF PRODUCING SUBSTANTIALLY UNIFORM, LARGE PARTICLE SIZE POLYMER BEADS WITH IMPROVED ELECTRICAL RESISTIVITY WHICH COMPRISES POLYMERIZING AT A TEMPERATURE OF BETWEEN ABOUT 30*C. AND 70*C. BY SUSPENSION POLYMERIZATION VINYL CHLORIDE WHILE DISPERSED IN AN AQUEOUS SUSPENSION MEDIUM CONTAINING DISSOLVED THEREIN A SALT OF A METAL HAVING A VALENCE OF AT LEAST 2 AND AT LEAST ONE SURFACE ACTIVE AGENT SELECTED FROM THE GROUP CONSISTING OF ALKYL PHOSPHATES AND ALKALI METAL SALTS THEREOF HAVING FROM ABOUT 5 TO 50 CARBON ATOMS, SAID METAL SALT AND SAID SURFACE ACTIVE AGENT EACH BEING PRESENT IN AN AMOUNT WITHIN THE RANGE OF ABOUT 0.02 TO ABOUT 0.20 PART PER 100 PARTS OF VINYL CHLORIDE.
Claim 2
Dependent Claim
112 words
THE PROCESS OF PRODUCING SUBSTANTIALLY UNIFORM, LARGE PARTICLE SIZE POLYMER BEADS WITH IMPROVED ELECTRICAL RESISTIVITY WHICH COMPRISES POLYMERIZING AT A TEMPERATURE OF BETWEEN ABOUT 30*C. AND 70*C. BY SUSPENSION POLYMERIZATION VINYL CHLORIDE WHILE DISPERSED IN AN AQUEOUS SUSPENSION MEDIUM CONTAINING DISSOLVED THEREIN A SALT OF A METAL HAVING A VALENCE OF AT LEAST 2 AND AT LEAST ONE SURFACE ACTIVE AGENT SELECTED FROM THE GROUP CONSISTING OF ALKYL PHOSPHATES AND ALKALI METAL SALTS THEREOF HAVING FROM ABOUT 5 TO 50 CARBON ATOMS, SAID METAL SALT AND SAID SURFACE ACTIVE AGENT EACH BEING PRESENT IN AN AMOUNT WITHIN THE RANGE OF ABOUT 0.02 TO ABOUT 0.20 PART PER 100 PARTS OF VINYL CHLORIDE.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-04-24 | 1964-10-24 | 1965-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-04-24 | 1968-10-24 | 1969-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-04-24 | 1972-10-24 | 1973-04-25 | $7700.00 | Window Closed / Lapsed |