 Toner for use in developing electrostatic images |
| What we claim is: 1. In a method of electrophotography comprising developing an electrostatic ... |
|
| Toner aggregation processes |
| What is claimed is: 1. A process for the preparation of toner compositions comprising: (i) forming ... |
|
| Toner |
| The present invention has been created in order to solve the problems as described above, and the ... |
|
| Toner with wax component for developing electrostatic image |
| An object of the present invention is to provide a toner for developing an electrostatic image ... |
|
| Coloring fine particle and toner for developing electrostatic images using the same |
| The objects of the present invention are achieved by coloring fine particles, produced by heating ... |
|
| Electronograph developing agent and method of manufacturing the same |
| The purpose of the present invention is to provide a developing agent which can be easily prepared ... |
|
| Coated carrier |
| What is claimed is: 1. A carrier comprised of a core and thereover a first polymer coating ... |
|
| Photoconductive composition |
| OF THE INVENTION The present invention embodies a photoconductive composition comprising a mixture ... |
|
|
Toner emulsion aggregation processes
| Details |
Inventors: Patel, Raj D.; Kmiecik-Lawrynowicz, Grazyna E.; Hopper, Michael A.;
Assignee: Xerox Corporation (Stamford, CT)
Primary Examiner: Goodrow; John
Assistant Examiner:
Attorney, Agent or Firm: Palazzo; E. O.
A process for the preparation of toner compositions with controlled particle size comprising: (i) preparing a pigment dispersion in water, which dispersion is comprised of pigment, an ionic surfactant, and an optional charge control agent; (ii) shearing at high speeds the pigment dispersion with a polymeric latex comprised of resin, a counterionic surfactant with a charge polarity of opposite sign to that of said ionic surfactant and a nonionic surfactant thereby forming a uniform homogeneous blend dispersion comprised of resin, pigment, and optional charge agent; (iii) heating the above sheared homogeneous blend below about the glass transition temperature (Tg) of the resin while continuously stirring to form electrostatically bounded toner size aggregates with a narrow particle size distribution; (iv) heating the statically bound aggregated particles above about the Tg of the resin particles to provide coalesced toner comprised of resin, pigment, and optional charge control agent, and subsequently optionally accomplishing (v) and (vi); (v) separating said toner; and (vi) drying said toner. |
|
DETAILED DESCRIPTION What is claimed is: 1.
A process for the preparation of toner compositions with controlled particle size consisting essentially of: (i) preparing a pigment dispersion in water, which dispersion is comprised of pigment, an ionic surfactant, and an optional charge control agent; (ii) shearing at high speeds the pigment dispersion with a polymeric latex comprised of resin, a counterionic surfactant with a charge polarity of opposite sign to that of said ionic surfactant and a nonionic surfactant thereby forming a uniform homogeneous blend dispersion comprised of resin, pigment, and optional charge agent; (iii) heating the above sheared homogeneous blend below about the glass transition temperature (Tg) of the resin while continuously stirring to form electrostatically bounded toner size aggregates with a narrow particle size distribution; (iv) heating the statically bound aggregated particles above about the Tg of the resin particles to provide coalesced toner comprised of resin, pigment, and optional charge control agent, and subsequently optionally accomplishing (v) and (vi); (v) separating said toner; and (vi) drying said toner.
2.
A process in accordance with claim 1 wherein the homogeneous dispersion of pigment and resin is dispersed in water containing surfactants, and enables a narrow particle size distribution or GSD of aggregates formed in (iii) of from about 1.
16 to about 1.
26.
3.
A process in accordance with claim 1 wherein the homogeneous blend (ii) is achieved by shearing the dispersion of the latex, the pigment and surfactants in water at a speed of from about 3,000 to about 15,000 revolutions per minute.
4.
A process in accordance with claim 1 wherein the shearing (ii) of the latex, pigment, and surfactants is achieved with a polytron or a homogenizer.
5.
A process in accordance with claim 1 wherein the shearing (ii) of the latex, pigment, and oppositely charged surfactants is achieved by a continuous shearing device with a variable gap adjustment of from about 0
|
| Related patents |
|
|
Production of surface-modified organic particles
OF THE INVENTION The organic particles (A) employed in the present invention may be prepared by art-known methods, such as melt-grinding method, suspension ...
|
|
|
Anti-solar polymers, method of making the same and cosmetic compositions containing the same
What is claimed is: 1. Anti-solar polymer having in the macromolecular chain thereof from 10 to 100% by weight of units of the formula ##EQU2## wherein F represents ##SPC...
|
|
|
Sunscreening compositions
We claim: 1. In a sunscreening composition comprising a pharmaceutical extending medium and an effective sunscreening amount of a dermally non-irritating, ultraviolet ...
|
|
|
4-(1,1-Dimethylethyl)-4'-methoxydibenzoylmethane
I claim: 1. 4-(1,1-Dimethylethyl)-4'-methoxydibenzoylmethane. 2. A light-screen composition comprising an effective ultra violet absorbing amount of 4-(1,1-dimethylethyl)...
|
|
|
Nitrobenzoyl-3-cyclopropylaminoacrylates and a process for the preparation thereof
OF THE INVENTION The detailed preparation method of nitrobenzoylester compounds of the formula (II) from dihalobenzene is described in the previous patent application S...
|
|
|
Unsaturated polyesters
The invention overcomes above-discussed problems in the prior art. The invention provides unbranched, linear polyester polymers, capable of undergoing subsequent cross-...
|
|
|
Toner composition for electrophotography with zinc oxide additive
OF THE INVENTION The colorants which can be used in the present invention typically include carbon black, Nigrosine, Aniline Blue, Chalcoyl Blue, Chrome Yellow, U...
|
|
|
Lithographic printing plate
OF THE INVENTION The lithographic printing plate according to the present invention can be prepared by forming a toner image by a conventional method, fixing or without ...
|
|
|
Toner for developing electrostatic charge image and process for preparing the same
An object of the present invention is to provide a toner having a small-particle-size which has good toner adhesion as well as good developing properties, ...
|
|
|
Piezo-active photoreceptor and system application
The deficiencies discussed above are overcome by the present invention. The charge retentive member of the invention described herein comprises a photoreceptive layer ...
|
|
|
Molecular Biology 
