US3918968A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrophotographic process utilizing carrier particles coated with a fluoropolymer in development
Assignee: International Business Machines Corp
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Filing: 1973-10-01
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Granted: 1975-11-11
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Expires: 1993-10-01
Abstract
Abstract An electrophotographic development carrier comprises core particles coated with a fluoropolymer or a mixture of a fluoropolymer and a modifying material. When utilized with appropriate electroscopic toner materials, the carrier, which is coated with the mixture of the fluoropolymer and the modifying material, is effective in producing a desired polarity and magnitude of the triboelectric charge on the toner particles, and the carrier, which is coated with the fluoropolymer, is effective, in producing a triboelectric charge of a desired magnitude on the toner particles. Control of the polarity and magnitude of the triboelectric charge characteristic of the carrier, which has its particles coated with the mixture of the fluoropolymer and the modifying material, is obtained by heating the coated particles to a selected temperature depending upon the desired polarity and magnitude and the particular toner with which the carrier is used. Control of the magnitude of the triboelectric charge characteristic of the carrier, which is coated with the fluoropolymer, is obtained by controlling the curing conditions.
Inventors
- 👤 William J Kukla
- 👤 Howard E Munzel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:31
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/10; G03G9/113; G03G9/1132; G03G9/1137; G03G9/1133; G03G9/1134; G03G9/1135
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
169 words
AN ELECTROPHOTOGRAPHIC PROCESS COMPRISING: FORMING AN ELECTROSTATIC IMAGE ON THE SURFACE OF A PHOTOCONDUCTIVE MEMBER, AND CONTACTING THE IMAGE WITH A DEVELOPER MMIXTURE COMPRISING FINELY DIVIDED TONER PARTICLES MIXED WITH CASSIER PARTICLES, EACH OF SAID CARRIER PARTICLES COMPRISING A CORE HAVING A SUBSTANTIALLY CONTINUOUS FILM FIRMLY ADHERED TO ITS SURFACE, SAID FILM BEING A MATERIAL SELECTED FROM A GROUP OF MATERIALS, WITH EACH OF THE MATERIALS COMPRISING A MIXTURE OF AN INHERENTLY TRIBOELECTRICALLY MEGATIVE FLUOROPOLYMER AND A MODIFYING RESIN IN WHICH THE FLUOROPOLYMER IS ESSENTIALLY INSOLUBLE, AND SAID CARRIER PARTICLES HAVING A DESIRED MAGNITUDE OF THE TRIBOELECTRIC CHARGE CHARACTERISTIC FOR A SELECTED COMPOSITION OF THE MATERIAL OF SAID TONER PARTICLES, A SELECTED PER CENT BY WEIGHT OF SAID TONER PARTICLES RELATIVE TO SAID CARRIER PARTICLES, AND THE ELECTROPHOTOGRAPHIC SYSTEM FROM WHICH THE DEVELOPER MATERIAL IS TO BE USED SELECTED FROM A GROUP OF POSSIBLE MAGNITUDES BY SELECTING THE CURING TEMPERATURE OF THE SELECTED MATERIAL OF SAID FILM WITH THE TEMPERATURE BEING IN A RANGE BETWEEN 300* AND 800* F.
Claim 2
Dependent Claim
169 words
AN ELECTROPHOTOGRAPHIC PROCESS COMPRISING: FORMING AN ELECTROSTATIC IMAGE ON THE SURFACE OF A PHOTOCONDUCTIVE MEMBER, AND CONTACTING THE IMAGE WITH A DEVELOPER MMIXTURE COMPRISING FINELY DIVIDED TONER PARTICLES MIXED WITH CASSIER PARTICLES, EACH OF SAID CARRIER PARTICLES COMPRISING A CORE HAVING A SUBSTANTIALLY CONTINUOUS FILM FIRMLY ADHERED TO ITS SURFACE, SAID FILM BEING A MATERIAL SELECTED FROM A GROUP OF MATERIALS, WITH EACH OF THE MATERIALS COMPRISING A MIXTURE OF AN INHERENTLY TRIBOELECTRICALLY MEGATIVE FLUOROPOLYMER AND A MODIFYING RESIN IN WHICH THE FLUOROPOLYMER IS ESSENTIALLY INSOLUBLE, AND SAID CARRIER PARTICLES HAVING A DESIRED MAGNITUDE OF THE TRIBOELECTRIC CHARGE CHARACTERISTIC FOR A SELECTED COMPOSITION OF THE MATERIAL OF SAID TONER PARTICLES, A SELECTED PER CENT BY WEIGHT OF SAID TONER PARTICLES RELATIVE TO SAID CARRIER PARTICLES, AND THE ELECTROPHOTOGRAPHIC SYSTEM FROM WHICH THE DEVELOPER MATERIAL IS TO BE USED SELECTED FROM A GROUP OF POSSIBLE MAGNITUDES BY SELECTING THE CURING TEMPERATURE OF THE SELECTED MATERIAL OF SAID FILM WITH THE TEMPERATURE BEING IN A RANGE BETWEEN 300* AND 800* F.
Claim 3
Dependent Claim
12 words
The process of claim 1 in which the fluoropolymer is a fluorocarbon.
Claim 4
Dependent Claim
16 words
The process of claim 2 in which the fluorocarbon is a copolymer of tetrafluoroethylene and hexafluoropropylene.
Claim 5
Dependent Claim
145 words
AN ELECTROPHOTOGRAPHIC PROCESS COMPRISING: FORMING AN ELECTROSTATIC IMAGE ON THE SURFACE OF A PHOTOCONDUCTIVE MEMBER, AND CONTAINING THE IMAGE WITH A DEVELOPER MIXTURE COMPRISING FINELY DIVIDED TONER PARTICLES MIXED WITH CARRIER PARTICLES, EACH OF SAID CARRIER PARTICLES COMPRISING A CORE HAVING A SUBSTANTIALLY CONTINUOUS FILM FIRMLY AADHERED TO ITS SURFACE, SAID FILM COMPRISING POLYTETRAFLUOROETHYLENE, AND SAID CARRIER PARTICLES HAVING THE MAGNITUDE OF THE TRIBOELECTRIC CHARGE CHARACTERISTIC FOR A SELECTED COMPOSITION OF THE MATERIAL OF SAID TONER PARTICLES, A SELECTED PER CENT BY WEIGHT OF SAID TONER PARTICLES RELATIVE TO SAID CARRIER PARTICLES, AND THE ELECTROPHOTOGRAPHIC SYSTEM WITH WHICH THE DEVELOPER MATERIAL IS TO BE USED SELECTED MATERIAL OF DANCE WITH THE CURING PROCESS OF THE SELECTED MATERIAL OF SAID FILM IN WHICH THE MATERIAL IS HEATED TO A TEMPERATURE IN A RANGE BETWEEN THE GLASS TRANSITION TEMPERATURE OF THE FLUOROPOLYMER AND 700*F AND THEN QUENCHED.
Claim 6
Dependent Claim
145 words
AN ELECTROPHOTOGRAPHIC PROCESS COMPRISING: FORMING AN ELECTROSTATIC IMAGE ON THE SURFACE OF A PHOTOCONDUCTIVE MEMBER, AND CONTAINING THE IMAGE WITH A DEVELOPER MIXTURE COMPRISING FINELY DIVIDED TONER PARTICLES MIXED WITH CARRIER PARTICLES, EACH OF SAID CARRIER PARTICLES COMPRISING A CORE HAVING A SUBSTANTIALLY CONTINUOUS FILM FIRMLY AADHERED TO ITS SURFACE, SAID FILM COMPRISING POLYTETRAFLUOROETHYLENE, AND SAID CARRIER PARTICLES HAVING THE MAGNITUDE OF THE TRIBOELECTRIC CHARGE CHARACTERISTIC FOR A SELECTED COMPOSITION OF THE MATERIAL OF SAID TONER PARTICLES, A SELECTED PER CENT BY WEIGHT OF SAID TONER PARTICLES RELATIVE TO SAID CARRIER PARTICLES, AND THE ELECTROPHOTOGRAPHIC SYSTEM WITH WHICH THE DEVELOPER MATERIAL IS TO BE USED SELECTED MATERIAL OF DANCE WITH THE CURING PROCESS OF THE SELECTED MATERIAL OF SAID FILM IN WHICH THE MATERIAL IS HEATED TO A TEMPERATURE IN A RANGE BETWEEN THE GLASS TRANSITION TEMPERATURE OF THE FLUOROPOLYMER AND 700*F AND THEN QUENCHED.
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) | 1978-11-10 | 1979-05-12 | 1979-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-10 | 1983-05-12 | 1983-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-10 | 1987-05-12 | 1987-11-11 | $7700.00 | Window Closed / Lapsed |