Developer composition for electrostatic latent images
AssigneeKao Corporation
InventorsHisakazu Tajima, Yukiya Sato, Masayuki Maruta, Atsushi Sonobe
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Abstract
The developer composition for electrostatic latent images includes a toner and a carrier, the toner including (a) a binder resin comprising a polyester resin having an acid value of from 0 to 10 KOH mg/g; (b) a wax; and (c) a colorant. In the developer composition, the wax is dispersed in the toner with a length to diameter ratio of from 2 to 15.
Claims15
A developer composition for electrostatic latent images comprising a toner and a carrier, the toner comprising:
- (a) a binder resin comprising a polyester resin having an acid value of from 0 to 10 KOH mg/g;
- (b) a wax;
- and
- (c) a colorant,
- wherein said wax is dispersed in the toner with a length to diameter ratio of from 2 to 15, and wherein said wax is one or more compounds selected from the group consisting of polyolefins having a weight-average molecular weight of 10,000 or less, metal salts of fatty acids, fatty acid esters, partially saponified fatty acid esters, higher fatty acids, higher alcohols, paraffin waxes, amide waxes, and polyhydric alcohol esters.
A process for producing a developer composition for electrostatic latent images comprising a toner and a carrier, the toner comprising a binder resin comprising a polyester resin having an acid value of from 0 to 10 KOH mg/g;
- a wax;
- and a colorant, wherein said wax is dispersed in the toner with a length to diameter ratio of from 2 to 15, the process comprising the steps of:
- (a) melt-kneading starting materials containing a binder resin, a wax, and a colorant;
- (b) cooling and solidifying the melt-kneaded mixture obtained in step (a) from a melt-kneading temperature to a solidification temperature at a cooling rate sufficient to give a length to diameter ratio of from 2 to 15, and wherein said wax is one or more compounds selected from the group consisting of polyolefins having a weight- average molecular weight of 10,000 or less, metal salts of fatty acids, fatty acid esters, partially saponified fatty acid esters, higher fatty acids, higher alcohols, paraffin waxes, amide waxes, and polyhydric alcohol esters;
- and
- (c) finely pulverizing and classifying the solidified product obtained in step (b), to give a toner.
Dependencies are inferred from the claim text.