Patent US3767578A successfully refreshed from Google Patents.
US3767578A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Carrier material for electrostatographic developer
Assignee: Xerox Corp
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Filing: 1971-06-10
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Granted: 1973-10-23
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Expires: 1991-06-10
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 15:44
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.
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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 |