← Back to Patent Explorer
US4894308A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for preparing electrophotographic toner

Assignee: Xerox Corp
•
Filing: 1988-10-17
•
Granted: 1990-01-16
•
Expires: 2008-10-17
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A process for preparing an electrophotographic toner composition which comprises premixing a pigment and a charge control additive in the absence of a solvent, subsequently admixing the premixed pigment and charge control additive and a resin, and extruding the pigment, charge control additive, and resin. The pigment and the charge control additive may be premixed prior to being added to the extruder with the resin; alternatively, the pigment and charge control additive may be premixed by adding them to the extruder via an upstream supply means and extruding them, and subsequently adding the resin to the extruder via a downstream supply means.

Inventors

  • 👤 Hadi K. Mahabadi
  • 👤 Sheau V. Kao
  • 👤 Gerald R. Allison
  • 👤 Hui Chang
  • 👤 Edward J. Gutman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 16:44
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/0802; G03G9/0812; G03G9/081

Claims Analysis

Total Claims: 38
Claim 1
Independent Claim 57 words
A process for preparing a toner composition which comprises (1) premixing a pigment and a charge control additive in the absence of a solvent; (2) subsequently admixing the premixed pigment and charge control additive obtained in step 1 with a resin; and (3) extruding the mixture of pigment, charge control additive, and resin obtained in step 2.
Claim 2
Dependent Claim 57 words
A process for preparing a toner composition which comprises (1) premixing a pigment and a charge control additive in the absence of a solvent; (2) subsequently admixing the premixed pigment and charge control additive obtained in step 1 with a resin; and (3) extruding the mixture of pigment, charge control additive, and resin obtained in step 2.
Claim 3
Dependent Claim 24 words
A process in accordance with claim 1 wherein the pigment and the charge control additive are premixed prior to being added to the extruder.
Claim 4
Dependent Claim 51 words
A process in accordance with claim 1 wherein the pigment and charge control additive are premixed by adding them to the extruder via a first upstream supply means and extruding them, and the resin is subsequently added to the extruder via a second supply means downstream of the first supply means.
Claim 5
Dependent Claim 19 words
A process in accordance with claim 2 wherein an additional amount of fresh pigment is added with the resin.
Claim 6
Dependent Claim 32 words
A process in accordance with claim 2 wherein the pigment and the charge control additive are premixed for from about 1 to about 8 minutes prior to the addition of the resin.
Claim 7
Dependent Claim 35 words
A process in accordance with claim 2 wherein the pigment is selected from the group consisting of carbon black, magnetites, cyan pigments, magenta pigments, yellow pigments, blue pigments, green pigments, brown pigments, and mixtures thereof.
Claim 8
Dependent Claim 32 words
A process in accordance with claim 2 wherein the resin is selected from the group consisting of polyimides, epoxies, diolefins, polyurethanes, vinyl resins, and esterification products of a di-acid and a diol.
Claim 9
Dependent Claim 32 words
A process in accordance with claim 2 wherein the charge control additive is selected from the group consisting of quaternary ammonium compounds, alkyl pyridinium compounds, organic sulfate compounds, and organic sulfonate compounds.
Claim 10
Dependent Claim 32 words
A process in accordance with claim 2 wherein the mixture of resin, pigment, and charge control additive is extruded for from about 2 to about 8 minutes after the resin is added.
Claim 11
Dependent Claim 29 words
A process in accordance with claim 2 wherein the pigment and the charge control additive are premixed at a temperature of from about 80° C. to about 150° C.
Claim 12
Dependent Claim 30 words
A process in accordance with claim 2 wherein the mixture of pigment, charge control additive, and resin is extruded at a temperature of from 100° C. to about 200° C.
Claim 13
Dependent Claim 19 words
A process in accordance with claim 3 wherein an additional amount of fresh pigment is added with the resin.
Claim 14
Dependent Claim 32 words
A process in accordance with claim 3 wherein the pigment and the charge control additive are premixed for from about 1 to about 8 minutes prior to the addition of the resin.
Claim 15
Dependent Claim 35 words
A process in accordance with claim 3 wherein the pigment is selected from the group consisting of carbon black, magnetites, cyan pigments, magenta pigments, yellow pigments, blue pigments, green pigments, brown pigments, and mixtures thereof.
Claim 16
Dependent Claim 32 words
A process in accordance with claim 3 wherein the resin is selected from the group consisting of polyimides, epoxies, diolefins, polyurethanes, vinyl resins, and esterification products of a di-acid and a diol.
Claim 17
Dependent Claim 32 words
A process in accordance with claim 3 wherein the charge control additive is selected from the group consisting of quaternary ammonium compounds, alkyl pyridinium compounds, organic sulfate compounds, and organic sulfonate compounds.
Claim 18
Dependent Claim 32 words
A process in accordance with claim 3 wherein the mixture of resin, pigment, and charge control additive is extruded for from about 2 to about 8 minutes after the resin is added.
Claim 19
Dependent Claim 29 words
A process in accordance with claim 3 wherein the pigment and the charge control additive are premixed at a temperature of from about 80° C. to about 150° C.
Claim 20
Dependent Claim 31 words
A process in accordance with claim 3 wherein the mixture of pigment, charge control additive, and resin is extruded at a temperature of from about 100° C. to about 200° C.
Claim 21
Dependent Claim 63 words
A process for preparing an electrophotographic toner composition which comprises (1) premixing carbon black and cetyl pyridinium chloride in the absence of a solvent; (2) subsequently admixing the premixed carbon black and cetyl pyridinium chloride obtained in step 1 with a styrene-n-butyl methacrylate copolymer resin; and (3) extruding the mixture of carbon black, cetyl pyridinium chloride, and copolymer resin obtained in step 2.
Claim 22
Dependent Claim 63 words
A process for preparing an electrophotographic toner composition which comprises (1) premixing carbon black and cetyl pyridinium chloride in the absence of a solvent; (2) subsequently admixing the premixed carbon black and cetyl pyridinium chloride obtained in step 1 with a styrene-n-butyl methacrylate copolymer resin; and (3) extruding the mixture of carbon black, cetyl pyridinium chloride, and copolymer resin obtained in step 2.
Claim 23
Dependent Claim 25 words
A process in accordance with claim 20 wherein the carbon black and the cetyl pyridinium chloride are premixed prior to being added to the extruder.
Claim 24
Dependent Claim 46 words
A process in accordance with claim 20 wherein the carbon black and cetyl pyridinium chloride are premixed by adding them to the extruder via an upstream supply means and extruding them, and the copolymer resin is subsequently added to the extruder via a downstream supply means.
Claim 25
Dependent Claim 21 words
A process in accordance with claim 20 wherein an additional amount of fresh carbon black is added with the copolymer resin.
Claim 26
Dependent Claim 34 words
A process in accordance with claim 20 wherein the carbon black and the cetyl pyridinium chloride are premixed for from about 1 to about 8 minutes prior to the addition of the copolymer resin.
Claim 27
Dependent Claim 34 words
A process in accordance with claim 20 wherein the mixture of copolymer resin, carbon black, and cetyl pyridinium chloride is extruded for from about 2 to about 8 minutes after the resin is added.
Claim 28
Dependent Claim 30 words
A process in accordance with claim 20 wherein the carbon black and the cetyl pyridinium chloride are premixed at a temperature of from about 80° C. to about 150° C.
Claim 29
Dependent Claim 33 words
A process in accordance with claim 20 wherein the mixture of carbon black, cetyl, pyridinium chloride, and copolymer resin is extruded at a temperature of from about 100° C. to about 200° C.
Claim 30
Dependent Claim 131 words
A process for preparing an electrophotographic toner composition which comprises (1) premixing carbon black and cetyl pyridinium chloride in the absence of a solvent for from about 1 to about 8 minutes at a temperature of from about 80° C. to about 150° C.; (2) subsequently adding a styrene-n-butyl methacrylate copolymer resin to the premixed carbon black and cetyl pyridinium chloride obtained in step 1; (3) extruding the mixture of carbon black, cetyl pyridinium chloride, and copolymer resin obtained in step 2 at a temperature of from about 100° C. to about 200° C. for from about 2 to about 8 minutes; (4) subsequently recovering the product obtained; and (5) reducing the product to particles with an average particle diameter of from about 10 to about 20 microns in average diameter.
Claim 31
Dependent Claim 131 words
A process for preparing an electrophotographic toner composition which comprises (1) premixing carbon black and cetyl pyridinium chloride in the absence of a solvent for from about 1 to about 8 minutes at a temperature of from about 80° C. to about 150° C.; (2) subsequently adding a styrene-n-butyl methacrylate copolymer resin to the premixed carbon black and cetyl pyridinium chloride obtained in step 1; (3) extruding the mixture of carbon black, cetyl pyridinium chloride, and copolymer resin obtained in step 2 at a temperature of from about 100° C. to about 200° C. for from about 2 to about 8 minutes; (4) subsequently recovering the product obtained; and (5) reducing the product to particles with an average particle diameter of from about 10 to about 20 microns in average diameter.
Claim 32
Dependent Claim 28 words
A process in accordance with claim 2 wherein the product recovered from the extruder is reduced to particles of from about 10 to about20 microns in average diameter.
Claim 33
Dependent Claim 29 words
A process in accordance with claim 3 wherein the product recovered from the extruder is reduced to particles of from about 10 to about 20 microns in average diameter.
Claim 34
Dependent Claim 29 words
A process in accordance with claim 20 wherein the product recovered from the extruder is reduced to particles of from about 10 to about 20 microns in average diameter.
Claim 35
Dependent Claim 26 words
A process in accordance with claim 2 wherein extrusion is effected by rotation of a screw at from about 50 to about 300 revolutions per minute.
Claim 36
Dependent Claim 26 words
A process in accordance with claim 3 wherein extrusion is effected by rotation of a screw at from about 50 to about 300 revolutions per minute.
Claim 37
Dependent Claim 26 words
A process in accordance with claim 20 wherein extrusion is effected by rotation of a screw at from about 50 to about 300 revolutions per minute.
Claim 38
Dependent Claim 25 words
Process in accordance with claim 28 wherein extrusion is effected by rotation of a screw at from about 50 to about 300 revolutions per minute.

References Cited (Backward Citations)

GB1037547A Cited
US3893934A Cited
US4110844A Cited
US4649005A Cited
US4621039A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-01-15 1993-07-17 1994-01-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-01-15 1997-07-17 1998-01-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-01-15 2001-07-17 2002-01-16 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag