US3922382A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing carrier particles
Assignee: International Business Machines Corp
•
Filing: 1973-10-01
•
Granted: 1975-11-25
•
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 16:12
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: 17
Claim 1
Independent Claim
154 words
A METHOD OF SELECTIVELY CONTROLLING THE MAGNITUDE OF THE TRIBOELECTRIC CHARGE CHARACTERISTIC OF AN ELECTROPHOTOGRAPHIC DEVELOPMENT CARRIER FOR USE WITH TONER PARTICLES IN AN ELECTROPHOTOGRAPHIC SYSTEM INCLUDING: COATING A PLURALITY OF CORE PARTICLES WHICH WILL WITHSTAND A SELECTED CURING WITH A SUBSTANTIALLY CONTINUOUS FILM OF A MATERIAL COMPRISING AT LEAST ESSENTIALLY A SUBSTANTIALLY INSOLUBLE FLUOROPOLYMER; AND SELECTING THE CURING OF THE COATING TO FIRMLY ADHERE THE COATING TO EACH OF THE CORE PARTICLES AND TO CONTROL THE MAGNITUDE OF THE TRIBOELECTRIC CHARGE CHARACTERISTIC OF THE ELECTROPHOTOGRAPHIC DEVELOPMENT CARRIER WITH RESPECT TO TONER PARTICLES OF A GIVEN COMPOSITION AND A GIVEN PERCENT BY WEIGHT OF SAID TONER PARTICLES RELATIVE TO SAID CARRIER AND A GIVEN ELECTROPHOTOGRAPHIC SYSTEM WITH WHICH THE CARRIER AND TONER PARTICLES ARE TO BE USED, SAID MAGNITUDE BEING WITHIN A RANGE TO PRODUCE GOOD QUALITY COPY WHEN USED IN SAID ELECTROPHOTOGRAPHIC SYSTEM, SAID COPY EXHIBITING GOOD EDGE DEFINITION AND IMAGE FILL CHARACTERISTICS.
Claim 2
Independent Claim
154 words
A METHOD OF SELECTIVELY CONTROLLING THE MAGNITUDE OF THE TRIBOELECTRIC CHARGE CHARACTERISTIC OF AN ELECTROPHOTOGRAPHIC DEVELOPMENT CARRIER FOR USE WITH TONER PARTICLES IN AN ELECTROPHOTOGRAPHIC SYSTEM INCLUDING: COATING A PLURALITY OF CORE PARTICLES WHICH WILL WITHSTAND A SELECTED CURING WITH A SUBSTANTIALLY CONTINUOUS FILM OF A MATERIAL COMPRISING AT LEAST ESSENTIALLY A SUBSTANTIALLY INSOLUBLE FLUOROPOLYMER; AND SELECTING THE CURING OF THE COATING TO FIRMLY ADHERE THE COATING TO EACH OF THE CORE PARTICLES AND TO CONTROL THE MAGNITUDE OF THE TRIBOELECTRIC CHARGE CHARACTERISTIC OF THE ELECTROPHOTOGRAPHIC DEVELOPMENT CARRIER WITH RESPECT TO TONER PARTICLES OF A GIVEN COMPOSITION AND A GIVEN PERCENT BY WEIGHT OF SAID TONER PARTICLES RELATIVE TO SAID CARRIER AND A GIVEN ELECTROPHOTOGRAPHIC SYSTEM WITH WHICH THE CARRIER AND TONER PARTICLES ARE TO BE USED, SAID MAGNITUDE BEING WITHIN A RANGE TO PRODUCE GOOD QUALITY COPY WHEN USED IN SAID ELECTROPHOTOGRAPHIC SYSTEM, SAID COPY EXHIBITING GOOD EDGE DEFINITION AND IMAGE FILL CHARACTERISTICS.
Claim 3
Dependent Claim
13 words
The method according to claim 1 in which the material is a fluoropolymer.
Claim 4
Dependent Claim
13 words
The method according to claim 2 in which the material is a fluorocarbon.
Claim 5
Dependent Claim
12 words
The method according to claim 3 in which the material is polytetrafluoroethylene.
Claim 6
Dependent Claim
27 words
The method according to claim 1 in which the material is a mixture of a fluoropolymer and a modifying resin in which the fluoropolymer is essentially insoluble.
Claim 7
Dependent Claim
58 words
The method according to claim 5 in which curing is obtained by heating the carrier particles to a selected temperature within a range between 300*F and 800*F for a sufficient period of time to adhere the coating to each of the carrier particles, the temperatuRe being selected in accordance with the controlled magnitude of the triboelectric charge characteristic.
Claim 8
Dependent Claim
28 words
The method according to claim 6 in which the fluoropolymer is a fluorocarbon and the modifying resin is selected from the group consisting of epoxy and urethane resins.
Claim 9
Dependent Claim
39 words
The method according to claim 1 in which curing is obtained by heating the material of said film to a temperature in a range between the glass transition temperature of the fluoropolymer and 800*F and then quenching the material.
Claim 10
Dependent Claim
13 words
The method according to claim 8 in which the fluoropolymer is a fluorocarbon.
Claim 11
Dependent Claim
12 words
The method according to claim 9 in which the fluorocarbon is polytetrafluoroethylene.
Claim 12
Dependent Claim
18 words
The method according to claim 1 in which the coating is applied by a fluidized bed coating process.
Claim 13
Independent Claim
189 words
A method of controlling the polarity and magnitude of the triboelectric charge characteristic of an electrophotographic development carrier for use with toner particles including: coating a plurality of core particles which will withstand a selected curing temperature with a mixture of a fluoropolymer and a modifying resing: selecting the temperature at which the coating is to be cured with the selected temperature being in the range between 300*F and 800*F to adhere the coating to each of the core particles and to produce a selected polarity and magnitude of the triboelectric charge on the carrier with respect to toner particles of a selected composition of material and a selected percent by weight of toner particles relative to said carrier and a given electrophotographic system with which the carrier and toner particles are to be used, said magnitude being within a range to produce good quality copy when used with said toner particles in an electrophotographic process, said copy exhibiting good edge definition and image fill characteristics; and curing the coating at the selected temperature for a time period sufficient to adhere the coating to each of the core particles.
Claim 14
Independent Claim
189 words
A method of controlling the polarity and magnitude of the triboelectric charge characteristic of an electrophotographic development carrier for use with toner particles including: coating a plurality of core particles which will withstand a selected curing temperature with a mixture of a fluoropolymer and a modifying resing: selecting the temperature at which the coating is to be cured with the selected temperature being in the range between 300*F and 800*F to adhere the coating to each of the core particles and to produce a selected polarity and magnitude of the triboelectric charge on the carrier with respect to toner particles of a selected composition of material and a selected percent by weight of toner particles relative to said carrier and a given electrophotographic system with which the carrier and toner particles are to be used, said magnitude being within a range to produce good quality copy when used with said toner particles in an electrophotographic process, said copy exhibiting good edge definition and image fill characteristics; and curing the coating at the selected temperature for a time period sufficient to adhere the coating to each of the core particles.
Claim 15
Dependent Claim
28 words
The method according to claim 12 in which the fluoropolymer is a fluorocarbon and the modifying resin is selected from the group consisting of epoxy and urethane resins.
Claim 16
Dependent Claim
18 words
The method according to claim 12 in which the coating is applied by a fluidized bed coating process.
Claim 17
Dependent Claim
15 words
The method according to claim 12 in which the core particles are a ferromagnetic material.
References Cited (Backward Citations)
US3062793A
Cited
US3194428A
Cited
US3344064A
Cited
US3533835A
Cited
US3873356A
Cited
US3787382A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-24 | 1979-05-26 | 1979-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-24 | 1983-05-26 | 1983-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-24 | 1987-05-26 | 1987-11-25 | $7700.00 | Window Closed / Lapsed |