Toner for electrostatic latent image development and method for producing toner for electrostatic latent image development
AssigneeKYOCERA Document Solutions Inc.
InventorHidetoshi Miyamoto
Life of this patent
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Abstract
Toner particles in a toner for electrostatic latent image development are formed by aggregating fine particles containing a binder resin and fine particles containing a release agent, or fine particles containing a binder resin and a release agent in an aqueous medium to form aggregated particles, and heating the aggregated particles in an aqueous medium to coalesce components contained in the aggregated particles. The binder resin is a polyester resin, and has a content of oligomers having a molecular weight of 1000 or less in the toner, measured under pre-determined conditions, of 1000 mass ppm or less based on the mass of the toner.
Claims3
Toner particles in a toner for electrostatic latent image development, which are formed by aggregating fine particles containing a binder resin and fine particles containing a release agent in an aqueous medium to form aggregated particles, or by aggregating fine particles containing a binder resin and a release agent in an aqueous medium to form aggregated particles, and heating the resulting aggregated particles in an aqueous medium to coalesce components contained in the aggregated particles,
- wherein the binder resin is a polyester resin,
- and wherein the toner has a component ratio Y (mass ppm) of oligomers having a molecular weight of 1000 or less in the toner, which is calculated in accordance with a method comprising the following steps (1) to (3), of 1000 mass ppm or less.
- (1) a step of obtaining a methanol extract, containing oligomer derived from the binder resin, by stirring 100 g of a sample of the toner for electrostatic latent image development in 500 g of methanol at 60° C. for 8 hours,
- (2) a step of measuring a content of oligomers having a molecular weight of 1000 or less of oligomers contained in the methanol extract, and obtaining a mass X (g) of the oligomers having a molecular weight of 1000 or less contained in the whole amount of the methanol extract, and
- (3) a step of calculating the component ratio in accordance with the following formula:
- Y=(X/100(the mass of the toner sample))×1000000.
Dependencies are inferred from the claim text.