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US4043929A Expired / Lapsed US ⏱️ 0.0 years remaining

Electrostatographic carrier composition

Assignee: Xerox Corp
•
Filing: 1974-08-26
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Granted: 1977-08-23
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Expires: 1994-08-26
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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 of active hydrogen containing materials by silylation. The controlled variation of the triboelectric behavior of functional polymers by silylation provides a means of attaining optimum triboelectric responses in development systems.

Inventors

  • 👤 Harry W. Gibson
  • 👤 Franklin D. Saeva

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 07:58
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/10; G03G9/113; G03G9/1132; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/105; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2991; Y10T428/2998

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 94 words
An electrostatographic carrier composition for use in developing electrostatic latent images on a recording surface, said carrier composition comprising carrier particles having an average particle diameter of between about 50 microns and about 1,000 microns, each of said carrier particles comprising a core surrounded by an outer coating of a polymer containing hydroxyl moieties, said polymer having been selected from the group consisting of styrene-alkylmethacrylates and styrene-alkylacrylates wherein said polymer has been exposed to systematic chemical alteration of said hydroxyl moieties by silylation to provide carrier particles characterized as having controlled triboelectric charging properties.
Claim 2
Dependent Claim 94 words
An electrostatographic carrier composition for use in developing electrostatic latent images on a recording surface, said carrier composition comprising carrier particles having an average particle diameter of between about 50 microns and about 1,000 microns, each of said carrier particles comprising a core surrounded by an outer coating of a polymer containing hydroxyl moieties, said polymer having been selected from the group consisting of styrene-alkylmethacrylates and styrene-alkylacrylates wherein said polymer has been exposed to systematic chemical alteration of said hydroxyl moieties by silylation to provide carrier particles characterized as having controlled triboelectric charging properties.
Claim 3
Dependent Claim 96 words
An electrostatographic carrier composition for use in developing electrostatic latent images on a recording surface, said carrier composition comprising carrier particles having an average particle diameter of between about 50 microns and about 1,000 microns, each of said carrier particles comprising a core surrounded by an outer coating of a polymer containing active hydrogen constituents, said polymer having been selected from the group consisting of styrene-alkyl-methacrylates and styrene-alkylacrylates wherein said polymer has been exposed to systematic chemical alteration of said active hydrogen constituents by silylation to provide carrier particles characterized as having controlled triboelectric charging properties.
Claim 4
Dependent Claim 96 words
An electrostatographic carrier composition for use in developing electrostatic latent images on a recording surface, said carrier composition comprising carrier particles having an average particle diameter of between about 50 microns and about 1,000 microns, each of said carrier particles comprising a core surrounded by an outer coating of a polymer containing active hydrogen constituents, said polymer having been selected from the group consisting of styrene-alkyl-methacrylates and styrene-alkylacrylates wherein said polymer has been exposed to systematic chemical alteration of said active hydrogen constituents by silylation to provide carrier particles characterized as having controlled triboelectric charging properties.
Claim 5
Dependent Claim 31 words
An electrostatographic carrier composition in accordance with claim 2 wherein said coating comprises from about 0.1 percent to about 10.0 percent by weight based on the weight of said carrier particles.
Claim 6
Dependent Claim 33 words
An electrostatographic carrier composition in accordance with claim 2 wherein said systematic chemical alteration of said polymer has been controlled stoichiometrically so as to provide closely controlled triboelectric properties to said carrier particles.
Claim 7
Dependent Claim 33 words
An electrostatographic carrier composition in accordance with claim 2 wherein said systematic chemical alteration of said polymer has been controlled kinetically so as to provide closely controlled triboelectric properties to said carrier particles.
Claim 8
Dependent Claim 30 words
An electrostatographic carrier composition in accordance with claim 2 wherein said coating is the product of silylation of said active hydrogen constituents of said polymer and said core is metallic.
Claim 9
Dependent Claim 44 words
An electrostatographic carrier composition in accordance with claim 6 wherein said coating is the product of silylation of said active hydrogen constitutents with at least one silylating agent selected from the group consisting of dimethylaminotrimethylsilane, dimethyl chlorosilane, trimethylchlorosilane, and polysiloxanes with reactive terminal moieties.
Claim 10
Dependent Claim 18 words
An electrostatographic carrier composition in accordance with claim 2 wherein said active hydrogen constituents comprise aromatic hydroxyl groups.
Claim 11
Dependent Claim 91 words
An electrostatographic developer composition comprising finely-divided toner particles electrostatically clinging to the surface of carrier particles having an average particle diameter of between about 50 microns and about 1,000 microns, each of said carrier particles comprising a core surrounded by an outer coating of a polymer containing active hydrogen constituents, said polymer having been selected from the group consisting of styrene-alkylmethacrylates and styrene-alkylacrylates wherein said polymer has been exposed to systematic chemical alteration of said active hydrogen constituents by silylation to provide carrier particles characterized as having controlled triboelectric charging properties.
Claim 12
Dependent Claim 91 words
An electrostatographic developer composition comprising finely-divided toner particles electrostatically clinging to the surface of carrier particles having an average particle diameter of between about 50 microns and about 1,000 microns, each of said carrier particles comprising a core surrounded by an outer coating of a polymer containing active hydrogen constituents, said polymer having been selected from the group consisting of styrene-alkylmethacrylates and styrene-alkylacrylates wherein said polymer has been exposed to systematic chemical alteration of said active hydrogen constituents by silylation to provide carrier particles characterized as having controlled triboelectric charging properties.

References Cited (Backward Citations)

US3223577A Cited
US3537882A Cited
US3526533A Cited
US3789796A Cited
US3666530A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-08-22 1981-02-21 1981-08-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-08-22 1985-02-21 1985-08-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-08-22 1989-02-21 1989-08-23 $7700.00 Window Closed / Lapsed

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