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US4248954A Expired / Lapsed US ⏱️ 0.0 years remaining

Coated carrier particles for use in electrophotographic process

Assignee: AB Dick Co
•
Filing: 1977-09-07
•
Granted: 1981-02-03
•
Expires: 1997-09-07
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Abstract

Abstract Carrier particles for use in an electrophotographic process are prepared by coating the surface of the carrier particles with a perfluoro carboxylic acid in a polymeric binder. The resulting carriers are long lived and capable of imparting a positive triboelectric charge to electroscopic powders mixed therewith.

Inventors

  • 👤 Pabitra Datta
  • 👤 Virgil W. Westdale
  • 👤 John Novotny, Jr.

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 03:06
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/10; G03G9/113; G03G9/1132; G03G9/1135; G03G9/1138

Claims Analysis

Total Claims: 25
Claim 1
Independent Claim 108 words
A carrier for use in electrophotographic development of latent electrostatic images capable of inducing an electrostatic charge in a toner mixed therewith which comprises a core member selected from the group consisting of metallic particles and siliceous particles to the surface of which is adhered a surface member selected from the group consisting of perfluorinated and substantially perfluorinated carboxylic acids containing from 3 to 18 carbon atoms and salts, esters and amides thereof in a polymeric binder therefor wherein said polymeric binder is selected from the group consisting of polycarbonate resins, polyester resins, polyamide resins, polyurethane resins, epoxy resins, acrylic resins, novolak resins, and heat curable silicone rubbers.
Claim 2
Dependent Claim 108 words
A carrier for use in electrophotographic development of latent electrostatic images capable of inducing an electrostatic charge in a toner mixed therewith which comprises a core member selected from the group consisting of metallic particles and siliceous particles to the surface of which is adhered a surface member selected from the group consisting of perfluorinated and substantially perfluorinated carboxylic acids containing from 3 to 18 carbon atoms and salts, esters and amides thereof in a polymeric binder therefor wherein said polymeric binder is selected from the group consisting of polycarbonate resins, polyester resins, polyamide resins, polyurethane resins, epoxy resins, acrylic resins, novolak resins, and heat curable silicone rubbers.
Claim 3
Dependent Claim 12 words
A composition according to claim 1 wherein said acid is perfluorooctanoic acid.
Claim 4
Dependent Claim 12 words
A composition according to claim 1 wherein said acid is perfluoropropionic acid.
Claim 5
Dependent Claim 12 words
A composition according to claim 1 wherein said acid is perfluorobutyric acid.
Claim 6
Dependent Claim 12 words
A composition according to claim 1 wherein said acid is perfluorodecanoic acid.
Claim 7
Dependent Claim 12 words
A composition according to claim 1 wherein said acid is 11-H-eicosafluoroundecanoic acid.
Claim 8
Dependent Claim 12 words
A composition according to claim 1 wherein said acid is perfluoroglutaric acid.
Claim 9
Dependent Claim 11 words
A composition according to claim 1 wherein said amide is perfluoroacetamide.
Claim 10
Dependent Claim 13 words
A composition according to claim 1 wherein said charge is of positive polarity.
Claim 11
Dependent Claim 11 words
A composition according to claim 1 wherein said particles are magnetic.
Claim 12
Dependent Claim 11 words
A composition according to claim 1 wherein said particles are non-magnetic.
Claim 13
Dependent Claim 11 words
A composition according to claim 1 wherein said particles are iron.
Claim 14
Dependent Claim 13 words
A composition according to claim 1 wherein said particles are spherical steel beads.
Claim 15
Dependent Claim 22 words
A composition according to claim 1 wherein said binder is a polyester comprising a copolymer of methyl vinyl ether and maleic anhydride.
Claim 16
Dependent Claim 13 words
A composition according to claim 1 wherein said binder is a polycarbonate resin.
Claim 17
Dependent Claim 12 words
A composition according to claim 1 wherein said binder is a silicone.
Claim 18
Dependent Claim 13 words
A composition according to claim 1 wherein said binder is a polyurethane resin.
Claim 19
Dependent Claim 133 words
A process for developing a latent electrostatic image which comprises mixing an electroscopic powder with a carrier comprising a member selected from the group consisting of metallic particles and siliceous particles to the surface of which is adhered a member selected from the group consisting of perfluorinated and substantially perfluorinated carboxylic acids containing from 3 to 18 carbon atoms and salts, esters and amides thereof in a polymeric binder therefor wherein said polymeric binder is selected from the group consisting of, polycarbonate resins, polyester resins, polyamide resins, polyurethane resins, epoxy resins, acrylic resins, novolak resins and heat curable silicone rubbers, to impart electrostatic charges to said electroscopic powder and said carrier, whereby said electroscopic powder is attracted to said carrier and transferring said electroscopic powder from said carrier to said latent electrostatic image.
Claim 20
Dependent Claim 133 words
A process for developing a latent electrostatic image which comprises mixing an electroscopic powder with a carrier comprising a member selected from the group consisting of metallic particles and siliceous particles to the surface of which is adhered a member selected from the group consisting of perfluorinated and substantially perfluorinated carboxylic acids containing from 3 to 18 carbon atoms and salts, esters and amides thereof in a polymeric binder therefor wherein said polymeric binder is selected from the group consisting of, polycarbonate resins, polyester resins, polyamide resins, polyurethane resins, epoxy resins, acrylic resins, novolak resins and heat curable silicone rubbers, to impart electrostatic charges to said electroscopic powder and said carrier, whereby said electroscopic powder is attracted to said carrier and transferring said electroscopic powder from said carrier to said latent electrostatic image.
Claim 21
Dependent Claim 17 words
A process according to claim 18 wherein a positive electrostatic charge is imparted to said electroscopic powder.
Claim 22
Dependent Claim 78 words
A carrier for use in electrophotographic development of latent electrostatic images capable of inducing an electrostatic charge in a toner mixed therewith which comprises a core member selected from the group consisting of metallic particles and siliceous particles to the surface of which is adhered a surface member selected from the group consisting of perfluorinated and substantially perfluorinated carboxylic acids containing from 3 to 18 carbon atoms and salts, esters and amides thereof in a polyamide binder therefor.
Claim 23
Dependent Claim 78 words
A carrier for use in electrophotographic development of latent electrostatic images capable of inducing an electrostatic charge in a toner mixed therewith which comprises a core member selected from the group consisting of metallic particles and siliceous particles to the surface of which is adhered a surface member selected from the group consisting of perfluorinated and substantially perfluorinated carboxylic acids containing from 3 to 18 carbon atoms and salts, esters and amides thereof in a polyamide binder therefor.
Claim 24
Dependent Claim 104 words
A process for developing a latent electrostatic image which comprises mixing an electroscopic powder with a carrier comprising a member selected from the group consisting of metallic particles and siliceous particles to the surface of which is adhered a member selected from the group consisting of perfluorinated and substantially perfluorinated carboxylic acids containing from 3 to 18 carbon atoms and salts, esters and amides thereof in a polyamide binder therefor to impart opposite electrostatic charges to said electroscopic powder and said carrier, whereby said electroscopic powder is attracted to said carrier and transferring said electroscopic powder from said carrier to said latent electrostatic image.
Claim 25
Dependent Claim 104 words
A process for developing a latent electrostatic image which comprises mixing an electroscopic powder with a carrier comprising a member selected from the group consisting of metallic particles and siliceous particles to the surface of which is adhered a member selected from the group consisting of perfluorinated and substantially perfluorinated carboxylic acids containing from 3 to 18 carbon atoms and salts, esters and amides thereof in a polyamide binder therefor to impart opposite electrostatic charges to said electroscopic powder and said carrier, whereby said electroscopic powder is attracted to said carrier and transferring said electroscopic powder from said carrier to said latent electrostatic image.

References Cited (Backward Citations)

US3857792A Cited
US3554932A Cited
US3922382A Cited
US3916064A Cited
US3922381A Cited
US4068017A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-02-03 1984-08-04 1985-02-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-02-03 1988-08-04 1989-02-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-02-03 1992-08-04 1993-02-03 $7700.00 Window Closed / Lapsed

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