Patent US4513074A successfully refreshed from Google Patents.
US4513074A
Expired / Lapsed
US
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Stable conductive developer compositions
Assignee: Xerox Corp
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Filing: 1983-06-06
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Granted: 1985-04-23
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Expires: 2003-06-06
Abstract
Abstract Disclosed is an improved stable developer composition which contains resin particles, pigment particles, colloidal silica additive particles, fatty acid metal salt additive particles, and uncoated ferrite carrier particles. One preferred specific developer composition disclosed is comprised of (1) first resin particles of styrene methacrylate copolymers, grafted with or containing a low molecular weight wax composition, (2) second resin particles of a styrene, acrylate, acrylonitrile terpolymer, (3) pigment particles, (4) colloidal silica additive particles, (4) fatty acid metal salt additive particles, and (5) uncoated ferrite carrier particles.
Inventors
- 👤 Robert J. Nash
- 👤 Kent A. Randall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:25
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/087; G03G9/08784; G03G9/08786; G03G9/08702; G03G9/08726; G03G9/08731; G03G9/08775; G03G9/08782; G03G9/10; G03G9/107; G03G9/108; G03G9/1085
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
62 words
An improved stable two-component conductive developer having a toner composition consisting essentially of (1) first resin particles of styrene methacrylate copolymers, grafted with or containing a low molecular weight wax composition, (2) second resin particles of a styrene, acrylate, acrylonitrile terpolymer, (3) pigment particles, (4) colloidal silica additive particles, (5) fatty acid metal salt additive particles, and (6) uncoated ferrite carrier particles.
Claim 2
Dependent Claim
62 words
An improved stable two-component conductive developer having a toner composition consisting essentially of (1) first resin particles of styrene methacrylate copolymers, grafted with or containing a low molecular weight wax composition, (2) second resin particles of a styrene, acrylate, acrylonitrile terpolymer, (3) pigment particles, (4) colloidal silica additive particles, (5) fatty acid metal salt additive particles, and (6) uncoated ferrite carrier particles.
Claim 3
Dependent Claim
23 words
An improved stable conductive developer composition in accordance with claim 1 wherein the first resin particles are comprised of a styrene n/butylmethacrylate copolymer.
Claim 4
Dependent Claim
50 words
An improved developer composition in accordance with claim 1 wherein the first resin particles are comprised of a styrene n-butylmethacrylate copolymer resin containing 58 percent by weight of styrene and 42 percent by weight of n-butylmethacrylate, or 65 percent by weight of styrene, and 35 percent by weight of n-butylmethacrylate.
Claim 5
Dependent Claim
28 words
An improved stable conductive developer composition in accordance with claim 1 wherein the second resin particles are comprised of a crosslinked terpolymer resin of styrene, butylacrylate, and acrylonitrile.
Claim 6
Dependent Claim
18 words
An improved stable conductive developer composition in accordance with claim 1 wherein the pigment particles are carbon black.
Claim 7
Dependent Claim
22 words
An improved stable conductive developer composition in accordance with claim 1 wherein the colloidal silica particles are comprised of silica oxide particles.
Claim 8
Dependent Claim
24 words
An improved stable conductive developer composition in accordance with claim 1 wherein the fatty acid metal salt additive particles are comprised of zinc stearate.
Claim 9
Dependent Claim
24 words
An improved stable conductive developer composition in accordance with claim 1 wherein the uncoated ferrite carrier particles are comprised of iron, zinc, and maganese.
Claim 10
Dependent Claim
26 words
An improved stable conductive developer composition in accordance with claim 1 wherein the uncoated ferrite carrier particles are comprised of iron, copper, nickel, zinc, and maganese.
Claim 11
Dependent Claim
32 words
An improved developer composition in accordance with claim 1 wherein the first resin particles contain therein polypropylene wax, or polyethylene wax, of a molecular weight of from about 1,000 to about 5,000.
Claim 12
Dependent Claim
75 words
An improved developer composition in accordance with claim 1 wherein the colloidal silica additive particles are present in an amount of from about 0.1 percent by weight to about 1 percent by weight, based on the weight of the toner particles and the fatty acid metal salt additive particles are present in an amount of from about 0.1 percent by weight to about 1 percent by weight, based on the weight of the toner particles.
Claim 13
Dependent Claim
25 words
An improved developer composition in accordance with claim 1 wherein the colloidal silica particles are present in an amount of about 0.7 percent by weight.
Claim 14
Dependent Claim
43 words
An improved developer composition in accordance with claim 1 wherein the fatty acid metal salt additive particles are present in an amount of from about 0.1 percent by weight to about 0.80 percent by weight, based on the weight of the toner particles.
Claim 15
Dependent Claim
42 words
An improved developer composition in accordance with claim 1 wherein the low molecular weight wax material is present in an amount of from about 1 percent by weight to about 10 percent by weight, based on the weight of the toner composition.
Claim 16
Dependent Claim
34 words
An improved developer composition in accordance with claim 1 wherein the low molecular weight wax material is present in an amount of from about 2 percent by weight to about 5 percent by weight.
Claim 17
Dependent Claim
56 words
An improved developer composition in accordance with claim 1 wherein the first resin particles are present in an amount of from about 30 percent by weight to about 75 percent by weight, and the second terpolymer resin particles are present in an amount of from about 15 percent by weight to about 60 percent by weight.
Claim 18
Dependent Claim
31 words
An improved developer composition in accordance with claim 1 wherein the pigment particles are present in an amount of from about 2 percent by weight to about 15 percent by weight.
Claim 19
Dependent Claim
24 words
An improved developer composition in accordance with claim 10, wherein the polyethylene is of a molecular weight of from about 1,000 to about 1,500.
Claim 20
Dependent Claim
23 words
An improved developer composition in accordance with claim 10, wherein the molecular weight of the polypropylene is from about 4,000 to about 5,000.
Claim 21
Dependent Claim
31 words
An improved developer composition in accordance with claim 1, wherein the developer possess a stable triboelectric charging value of from about 10 microcoulombs per gram to about 40 microcoulombs per gram.
Claim 22
Dependent Claim
30 words
An improved developer composition in accordance with claim 1, wherein the carrier particles are of a conductivity of from about 10 -9 ohm/cm (-1) to about 10 -12 ohm/cm (-1).
Claim 23
Dependent Claim
22 words
An improved developer composition in accordance with claim 1, wherein the breakdown potentials for the carrier particles is greater than 1,000 volts.
Claim 24
Dependent Claim
25 words
An improved developer composition in accordance with claim 1, wherein the conductivity sensitivity parameter for the developer composition is from about 0.1 to about 0.9.
Claim 25
Dependent Claim
155 words
An improved stable two-component conductive developer having a toner composition consisting essentially of (1) from about 30% by weight to about 75% by weight of first resin particles of styrene methacrylate copolymers grafted with or containing a waxy material selected from the group consisting of polyethylene of a molecular weight of from about 1,000 to about 1,500, and polypropylene of a molecular weight of from about 1,000 to about 5,000, (2) second resin particles of a styrene, acrylate, acrylonitrile terpolymer, (3) pigment particles, (4) colloidal silica additive particles, (5) fatty acid metal salt additive particles, and uncoated ferrite carrier particles, and wherein the resulting composition has a stable triboelectric charge of from about 10 microcoulombs per gram to about 40 microcoulombs per gram, and the carrier conductivity is from about 10 -9 ohm/cm (-1) to about 10 -12 ohm/cm (-1), with the conductivity sensitivity parameter of this composition being from about 0.1 to about 0.9.
Claim 26
Dependent Claim
155 words
An improved stable two-component conductive developer having a toner composition consisting essentially of (1) from about 30% by weight to about 75% by weight of first resin particles of styrene methacrylate copolymers grafted with or containing a waxy material selected from the group consisting of polyethylene of a molecular weight of from about 1,000 to about 1,500, and polypropylene of a molecular weight of from about 1,000 to about 5,000, (2) second resin particles of a styrene, acrylate, acrylonitrile terpolymer, (3) pigment particles, (4) colloidal silica additive particles, (5) fatty acid metal salt additive particles, and uncoated ferrite carrier particles, and wherein the resulting composition has a stable triboelectric charge of from about 10 microcoulombs per gram to about 40 microcoulombs per gram, and the carrier conductivity is from about 10 -9 ohm/cm (-1) to about 10 -12 ohm/cm (-1), with the conductivity sensitivity parameter of this composition being from about 0.1 to about 0.9.
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) | 1988-04-22 | 1988-10-22 | 1989-04-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-22 | 1992-10-22 | 1993-04-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-22 | 1996-10-22 | 1997-04-23 | $7700.00 | Window Closed / Lapsed |