US2891921A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stabilization of polytetrafluoroethylene filler slurries
Assignee: EIDP Inc
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Filing: 1955-09-22
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Granted: 1959-06-23
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Expires: 1975-09-22
Abstract
No abstract record available.
Inventors
- 👤 Kumnick Miles Charles
- 👤 Lontz John Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:45
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/0008; C08K5/0075; Y; Y10; Y10S; Y10S277/00; Y10S277/935; Y10S277/944; Y10S277/945; Y10S277/946
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
115 words
IN THE PROCESS OF PREPARING MIXTURES OF INORGANIC FILLER AND POLYTRAFLUOROETHYLENE WHEREIN AN AQUEOUS DISPERSION OF POLYTRAFLUOROETHYLENE CONTAINING AS A DISPERSING AGENT A NON-IONIC SURFACE-ACTIVE AGENT IS COAGULATED BY THE ADDITION OF AN ELECTROLYTE ONTO AN INORGANIC CODISPERSED FILLER OF THE CLASS CONSISTING OF SILICA AND CARBON TO FORM AN AQUEOUS SLURRY OF SAID POLYTETRAGLUOROETHYLENE AND FILLER, THE STEP WHICH COMPRISES ADDING, AFTER THE SAID COAGULATION OF THE POLYTETRAFLUOROETHYLENE, FROM 0.5 TO 10% BY WEIGHT OF THE POLYTETRAFLUOROETHYLENE OF AN IONIC SURFACE-ACTIVE AGENT OF THE CLASS CONSISTING OF THE SODIUM SALT OF LAURYL ALCOHOL SULFATE AND STEARYL DIMETHYL BENZYL AMMONIUM CHLORIDE TO SAID SLURRY, WHEREBY AN IMPROVED COMPOSITION OF INORGANIC FILLER AND POLYTETRAFLUOROETHYLENE IS OBTAINED.
Claim 2
Dependent Claim
115 words
IN THE PROCESS OF PREPARING MIXTURES OF INORGANIC FILLER AND POLYTRAFLUOROETHYLENE WHEREIN AN AQUEOUS DISPERSION OF POLYTRAFLUOROETHYLENE CONTAINING AS A DISPERSING AGENT A NON-IONIC SURFACE-ACTIVE AGENT IS COAGULATED BY THE ADDITION OF AN ELECTROLYTE ONTO AN INORGANIC CODISPERSED FILLER OF THE CLASS CONSISTING OF SILICA AND CARBON TO FORM AN AQUEOUS SLURRY OF SAID POLYTETRAGLUOROETHYLENE AND FILLER, THE STEP WHICH COMPRISES ADDING, AFTER THE SAID COAGULATION OF THE POLYTETRAFLUOROETHYLENE, FROM 0.5 TO 10% BY WEIGHT OF THE POLYTETRAFLUOROETHYLENE OF AN IONIC SURFACE-ACTIVE AGENT OF THE CLASS CONSISTING OF THE SODIUM SALT OF LAURYL ALCOHOL SULFATE AND STEARYL DIMETHYL BENZYL AMMONIUM CHLORIDE TO SAID SLURRY, WHEREBY AN IMPROVED COMPOSITION OF INORGANIC FILLER AND POLYTETRAFLUOROETHYLENE IS OBTAINED.
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) | 1962-06-22 | 1962-12-22 | 1963-06-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-06-22 | 1966-12-22 | 1967-06-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-06-22 | 1970-12-22 | 1971-06-23 | $7700.00 | Window Closed / Lapsed |