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US3767578A Expired / Lapsed US ⏱️ 0.0 years remaining

Carrier material for electrostatographic developer

Assignee: Xerox Corp
•
Filing: 1971-06-10
•
Granted: 1973-10-23
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Expires: 1991-06-10
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Abstract

Abstract An electrostatographic developer mixture comprising nodular carrier beads, the nodular beads having a number average size distribution in the range of 50 to 1,000 microns, and between about 95 and about 99.5 weight percent, based upon the developer mixture, of carrier beads relative to the finely divided toner particles electrostatically clinging to the surface of the nodular carrier beads. Such developer mixtures are useful in the development of latent electrostatographic images by cascade and magnetic brush development techniques.

Inventors

  • 👤 R Hagenbach
  • 👤 M Lenhard

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 06:24
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/10; G03G9/113; G03G9/1132; G03G9/1133; G03G9/103; G03G9/107; G03G9/1075; G03G9/1087; G03G9/1139

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 15 words
An electrostatographic developer mixture according to claim 1 wherein the nodular carrier beads are metal.
Claim 2
Dependent Claim 15 words
An electrostatographic developer mixture according to claim 2 wherein the nodular carrier beads are nickel.
Claim 3
Dependent Claim 14 words
An electrostatographic developer mixture according to claim 2 wherein the carrier beads are iron.
Claim 4
Dependent Claim 29 words
An electrostatographic developer mixture according to Claim 1 wherein said nodular particles form into agglomerates and have an average size distribution in the range of 1 to 44 microns.
Claim 5
Dependent Claim 78 words
An electrostatographic developer mixture comprising carrier beads and finely divided toner particles electrostatically clinging to the surface of said beads, each said bead comprising an irregular surfaced generally spherical three dimensional solid, the irregular surface characterized by a plurality of raised generally spheroidally shaped nodular particles separated by recesses forming the junctions between adjacent ones of said nodular particles, said recesses providing traps for accumulations of said toner particles, thereby increasing the toner carrying capacity of said bead.
Claim 6
Dependent Claim 15 words
An electrostatographic developer mixture according to claim 6 wherein the nodular carrier beads are metal.
Claim 7
Dependent Claim 15 words
An electrostatographic developer mixture according to claim 7 wherein the nodular carrier beads are nickel.
Claim 8
Dependent Claim 14 words
An electrostatographic developer mixture according to claim 7 wherein the carrier beads are iron.
Claim 9
Dependent Claim 29 words
An electrostatographic developer mixture according to claim 6 wherein said nodular particles form as agglomerates and have an average size distribution in the range of 1 to 44 microns.
Claim 10
Dependent Claim 74 words
An electrostatographic developer mixture comprising nodular carrier beads each having a generally spherical shape and a surface characterized by a plurality of small generally rounded nodular particles separated by recesses, said beads having an average size distribution in the range of 50 to 1,000 microns, and at least about 0.5 weight percent, based on the weight of the developer mixture, of finely divided toner particles electrostatically clinging to the surface of the carrier beads.
Claim 11
Dependent Claim 75 words
An electrostatographic developer mixture comprising nodular carrier beads each having a generally spherical shape and a surface characterized by a plurality of small generally rounded nodular particles, said beads having an average size distribution in the range of 50 to 1,000 microns and between about 0.5 and at least about 2.2 weight percent, based on the weight of the developer mixture, of finely divided toner particles electrostatically clinging to the surface of the carrier beads.

References Cited (Backward Citations)

US2638416A Cited
US2965573A Cited
US3093039A Cited
US3079342A Cited
US3124457A Cited
US3278439A Cited
US3533835A Cited
US3607342A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-10-22 1977-04-23 1977-10-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-10-22 1981-04-23 1981-10-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-10-22 1985-04-23 1985-10-23 $7700.00 Window Closed / Lapsed

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