Patent US4152279A successfully refreshed from Google Patents.
US4152279A
Expired / Lapsed
US
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Triboelectric modified carrier for electrostatographic developer
Assignee: Xerox Corp
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Filing: 1977-09-26
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Granted: 1979-05-01
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Expires: 1997-09-26
Abstract
Abstract Electrostatographic developer compositions for use in developing electrostatic latent images wherein the triboelectric charging potential of functional polymers employed in the carrier materials are controlled through chemical alteration by acylation of hydroxyl and amino functions. The controlled variation of the triboelectric behavior of functional polymers by acylation provides a means of attaining optimum triboelectric responses in development systems.
Inventors
- 👤 Joseph L. Mincer
- 👤 Harry W. Gibson
- 👤 Frank C. Bailey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:29
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/10; G03G9/113; G03G9/1132; G03G9/1133; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/105
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
111 words
An electrostatographic developer composition comprising finely-divided toner particles electrostatically clinging to the surface of carrier particles having an average particle diameter between about 50 microns and about 1,000 microns, each of said carrier particles comprising a core surrounded by from about 0.1 percent to about 10.0 percent by weight based on the weight of said carrier particles of an outer coating of a polymer selected from the group consisting of styrene-alkylmethacrylate and styrene-alkylacrylate containing pendant hydroxyl and amino moieties, said polymer having been exposed to systematic chemical modification of the pendant hydroxyl and amino moieties of said polymer by acylation to provide carrier particles characterized as having controlled triboelectric charging properties.
Claim 2
Dependent Claim
111 words
An electrostatographic developer composition comprising finely-divided toner particles electrostatically clinging to the surface of carrier particles having an average particle diameter between about 50 microns and about 1,000 microns, each of said carrier particles comprising a core surrounded by from about 0.1 percent to about 10.0 percent by weight based on the weight of said carrier particles of an outer coating of a polymer selected from the group consisting of styrene-alkylmethacrylate and styrene-alkylacrylate containing pendant hydroxyl and amino moieties, said polymer having been exposed to systematic chemical modification of the pendant hydroxyl and amino moieties of said polymer by acylation to provide carrier particles characterized as having controlled triboelectric charging properties.
Claim 3
Dependent Claim
31 words
An electrostatographic developer composition in accordance with claim 1 wherein said coating comprises from about 0.1 percent to about 1.0 percent by weight based on the weight of said carrier particles.
Claim 4
Dependent Claim
34 words
An electrostatographic developer composition in accordance with claim 1 wherein said systematic chemical modification of said polymer has been controlled stoichiometrically so as to provide said controlled triboelectric charging properties to said carrier particles.
Claim 5
Dependent Claim
34 words
An electrostatographic developer composition in accordance with claim 1 wherein said systematic chemical modification of said polymer has been controlled kinetically so as to provide said controlled triboelectric charging properties to said carrier particles.
Claim 6
Dependent Claim
33 words
An electrostatographic developer composition in accordance with claim 1 wherein said triboelectric charging properties of said carrier particles have been controlled by the amount and type of acylating agent employed in said acylation.
Claim 7
Dependent Claim
28 words
An electrostatographic developer composition in accordance with claim 1 wherein said polymer has been crosslinked by reaction of said pendant hydroxyl and amino moieties with a crosslinking agent.
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) | 1982-04-30 | 1982-10-30 | 1983-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-04-30 | 1986-10-30 | 1987-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-04-30 | 1990-10-30 | 1991-05-01 | $7700.00 | Window Closed / Lapsed |