Positively chargeable toner
AssigneeKao Corporation
InventorsYutaka Kanamaru, Masahito Yamazaki, Jiro Takemoto
Life of this patent
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Abstract
A positively chargeable toner comprising a resin binder, a specified compound represented by the formula (I), and a higher fatty acid with a long-chain alkyl group having 8 to 22 carbon atoms and/or a metal salt thereof. The positively chargeable toner is a positively chargeable toner used for the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.
Claims13
A positively chargeable color toner comprising:
- a resin binder composed of a polyester and/or a hybrid resin in which a polyester component and a vinyl resin component are partially chemically bonded to each other;
- a compound represented by the formula (I):
- wherein each of R1 to R4, which may be identical or different, is hydrogen atom, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, an aryl group having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms;
- each of R5 to R12, which may be identical or different, is a hydrogen atom, an alkyl group having 1 to 30 carbon atoms or an alkenyl group having 2 to 30 carbon atoms;
- and M is a hydrogen atom or a monovalent metal ion;
- lithium stearate;
- and
- at least one colorant selected from the group consisting of Pigment Yellow 185,Pigment Red 122, and Pigment Blue 16,
- wherein the compound represented by the formula (I) is contained in an amount of from 0.1 to 3 parts by weight based on 100 parts by weight of the resin binder, and wherein a total amount of the lithium stearate is from 0.5 to 3 parts by weight based on 100 parts by weight of the resin binder, and
- wherein the toner is prepared by a method comprising the steps of mixing raw materials comprising the resin binder, the compound represented by the formula (I), the lithium stearate, and the colorant, and melt-kneading the mixture.
A two-component developer, which comprises a color toner mixed with a carrier at a ratio of 0.5/100 to 8/100 of the toner to the carrier, wherein said color toner is a positively chargeable color toner comprising:
- a resin binder composed of a polyester and/or a hybrid resin in which a polyester component and a vinyl resin component are partially chemically bonded to each other;
- a compound represented by the formula (I):
- wherein each of R1 to R4, which may be identical or different, is hydrogen atom, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, an aryl group having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms;
- each of R5 to R12, which may be identical or different, is a hydrogen atom, an alkyl group having 1 to 30 carbon atoms or an alkenyl group having 2 to 30 carbon atoms;
- and M is a hydrogen atom or a monovalent metal ion;
- lithium stearate;
- and
- at least one colorant selected from the group consisting of Pigment Yellow 185, Pigment Red 122, and Pigment Blue 16,
- wherein the compound represented by the formula (I) is contained in an amount of from 0.1 to 3 parts by weight based on 100 parts by weight of the resin binder, and wherein a total amount of the lithium stearate is from 0.5 to 3 parts by weight based on 100 parts by weight of the resin binder and
- wherein the toner is prepared by a method comprising the steps of mixing raw materials comprising the resin binder, the compound represented by the formula (I), the lithium stearate, and the colorant, and melt-kneading the mixture.
Dependencies are inferred from the claim text.