Toner processes using sodium sulfonated polyester resins

A surfactant free process for the preparation of toner compositions comprising:

• (i) preparing an emulsion latex comprised of sodium sulfonated polyester resin particles of less than 0.1 micron in size by heating said resin in water at a temperature of from about 15 to about 30.degree. C. above its glass transition temperature;
• (ii) preparing a pigment dispersion in water by dispersing in a 3 to 1 ratio said sodium sulfonated polyester particles to water with pigment using a microfluidizer at from about 75.degree. C. to about 85.degree. C. for a duration of from about 1 hour to about 3 hours;
• (iii) adding the pigment dispersion to a latex mixture comprised of sodium sulfonated polyester resin particles in water with shearing, and followed by the addition of an alkali halide of from about 1 to about 2 weight percent in water until gellation occurred as indicated by an increase in viscosity of from about 2 centipoise to about 100 centipoise;
• (iv) heating the resulting mixture below about the resin Tg at a temperature of from about 35.degree. C. to about 80.degree. C. thereby causing further aggregation and coalescence to result in toner particles of from about 4 to about 9 microns in size with a geometric distribution of less than about 1.3;
• and
• (v) cooling the product mixture to about 25.degree. C., and followed by washing and drying.

A process for the preparation of toner compositions comprising:

• (i) preparing an emulsion latex comprised of sodium sulfonated polyester resin particles by heating said resin in water;
• (ii) preparing a pigment dispersion in a water by dispersing in water a sodium sulfonated polyester and pigment;
• (iii) adding the pigment dispersion to a latex mixture comprised of sodium sulfonated polyester resin particles in water with shearing, followed by the addition of an alkali halide;
• and
• (iv) heating the resulting mixture thereby causing further aggregation and enabling coalescence.