US 5,472,819 AGranted

Toner and developer composition containing the same

AssigneeKao Corporation

InventorsNirohiro Hayashi, Kanji Yoshimura, Tohru Katoh, Kuniyasu Kawabe

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Abstract

A developer composition of the present invention contains a toner having at least a binder resin, a coloring agent and a toner scum preventive. The binder resin contains as a main component a polyester resin or a resin produced by concurrently carrying out addition polymerization and condensation polymerization in one reaction vessel. By using the toner of the present invention, since the formation of toner scum on the carrier surface can be prevented for a long period of time in the service life of the developer while retaining the low-temperature fixing ability of the toner, the carrier resistance and the triboelectric charge can be stably maintained, thereby providing a developer composition with a long service life. Accordingly, besides having a long service life mentioned above, the developer composition is highly suitably used for a high-speed semiconductive magnetic development.

Claims11

Dependent claims

A toner for two-component development comprising at least a binder resin and a coloring agent, wherein said binder resin comprises as a main component a polyester resin or a resin produced by carrying out concurrently addition polymerization and condensation polymerization in one reaction vessel, the toner containing in an inner portion thereof at least one of toner scum preventatives selected from the group consisting of:

(a) an aliphatic acid, metal salts thereof, and mixtures thereof;
(b) a monoalkyl phosphate, a dialkyl phosphate, and mixtures thereof;
(c) carbonyloxy and amido groups-containing amine, salts thereof, and mixtures thereof;
and
(d) a compound having the following general formula (D-1):
##STR14## wherein R.sup.1 represents an alkyl group, aralkyl group or alkenyl group, each having 7 to 24 carbon atoms;
A and A', which may be identical or different, independently represent a hydrogen atom, methyl group or --CH.sub.2 CH.sub.2 OR.sup.2, wherein R.sup.2 represents a hydrogen atom, an alkyl group, aralkyl group or alkenyl group, each having 8 to 24 carbon atoms, or ##STR15## wherein R.sup.3 represents an alkyl group, aralkyl group or alkenyl group, each having 8 to 24 carbon atoms;
and n is equal to 0 to 1, and wherein said toner is prepared by a method comprising the step of mixing said toner scum preventatives with said binder resin.

5 more elements

Dependencies are inferred from the claim text.