Toner aggregation processes
First Claim
1. A process for the preparation of toner compositions comprising:
- (i) preparing a pigment dispersion, which dispersion is comprised of a pigment, an ionic surfactant, and optionally a charge control agent;
(ii) shearing said pigment dispersion with a latex or emulsion blend comprised of resin, a counterionic surfactant with a charge polarity of opposite sign to that of said ionic surfactant and a nonionic surfactant;
(iii) heating the above sheared blend below about the glass transition temperature (Tg) of the resin, to form electrostatically bound toner size aggregates with a narrow particle size distribution; and
(iv) heating said bound aggregates above about the Tg of the resin.
4 Assignments
0 Petitions
Accused Products
Abstract
A process for the preparation of toner compositions comprising:
(i) preparing a pigment dispersion, which dispersion is comprised of a pigment, an ionic surfactant, and optionally a charge control agent;
(ii) shearing said pigment dispersion with a latex or emulsion blend comprised of resin, a counterionic surfactant with a charge polarity of opposite sign to that of said ionic surfactant and a nonionic surfactant;
(iii) heating the above sheared blend below about the glass transition temperature (Tg) of the resin, to form electrostatically bound toner size aggregates with a narrow particle size distribution; and
(iv) heating said bound aggregates above about the Tg of the resin.
546 Citations
48 Claims
-
1. A process for the preparation of toner compositions comprising:
-
(i) preparing a pigment dispersion, which dispersion is comprised of a pigment, an ionic surfactant, and optionally a charge control agent; (ii) shearing said pigment dispersion with a latex or emulsion blend comprised of resin, a counterionic surfactant with a charge polarity of opposite sign to that of said ionic surfactant and a nonionic surfactant; (iii) heating the above sheared blend below about the glass transition temperature (Tg) of the resin, to form electrostatically bound toner size aggregates with a narrow particle size distribution; and (iv) heating said bound aggregates above about the Tg of the resin. - View Dependent Claims (4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 22, 23, 24, 25, 26, 27, 28, 29, 30, 33, 34, 35, 38, 39, 40, 41, 42, 43, 44)
-
- 2. A process in accordance with claim I wherein the temperature below the resin Tg of (iii) controls the size of the aggregated particles in the range of from about 2.5 to about 10 microns in average volume diameter.
-
3. A process in accordance with claim I wherein the size of said aggregates can be increased to from about 2.5 to about 10 microns by increasing the temperature of heating in (iii) to from about room temperature to about 50°
- C.
-
36. 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 a pigment of a diameter of from about 0.01 to about 1 micron, and an ionic surfactant; (ii) shearing the pigment dispersion with a latex blend comprised of resin of submicron size of from about 0.01 to about 1 micron, a counterionic surfactant with a charge polarity of opposite sign to that of said ionic surfactant and a nonionic surfactant thereby causing a flocculation or heterocoagulation of the formed particles of pigment, and resin to form a uniform dispersion of solids in the water and surfactant; (iii) heating the above sheared blend at a temperature of from about 5°
to about 20°
C. below the Tg of the resin to form electrostatically bound toner size aggregates with a narrow particle size distribution;(iv) heating the statically bound aggregated particles at a temperature of from about 5 to about 50°
C. above the Tg of the resin to provide a mechanically stable toner composition comprised of polymeric resin and pigment; and
optionally(v) separating said toner particles; and (vi) drying said toner particles. - View Dependent Claims (45, 46)
-
-
37. A process for the preparation of toner compositions comprising:
-
(i) preparing a pigment dispersion in water, which dispersion is comprised of a pigment and an ionic surfactant; (ii) shearing the pigment dispersion with a latex blend comprised of resin of submicron size, a counterionic surfactant with a charge polarity of opposite sign to that of said ionic surfactant and a nonionic surfactant thereby causing a flocculation or heterocoagulation of the formed particles of pigment, resin and charge control agent to form a uniform dispersion of solids in the water and surfactant; (iii) heating the above sheared blend below about or about equal to the glass transition temperature (Tg) of the resin to form electrostatically bound toner size aggregates with a narrow particle size distribution; (iv) heating the statically bound aggregated particles above about or about equal to the Tg of the resin particles to provide a toner composition comprised of resin;
followed by optionally(v) separating said toner particles from said water by filtration; and (vi) drying said toner particles. - View Dependent Claims (47, 48)
-
Specification