Abstract: A toner for electrophotography comprising a charge control agent comprising a specified iron-azo complex or a specified metal compound of a benzilic acid derivative, a colorant, and a resin binder comprising a polyester, the polyester being a polyester obtained by polycondensing an alcohol component containing a propylene oxide adduct of bisphenol A and a carboxylic acid component, wherein the propylene oxide adduct of bisphenol A has an average mole of propylene oxide added of from 2.4 to 4.0, and wherein an adduct with 2 mol of propylene oxide is contained in an amount of 60% by mol or less, and an adduct with 4 mol of propylene oxide is contained in an amount of 10% by mol or more, of the propylene oxide adduct of bisphenol A, and wherein the propylene oxide adduct of bisphenol A has a content ratio of primary hydroxyl groups of 10% by mol or less of the entire hydroxyl groups.

Abstract: A toner for electrophotography comprising a charge control agent comprising a specified iron-azo complex or a specified metal compound of a benzilic acid derivative, a colorant, and a resin binder comprising a polyester, the polyester being a polyester obtained by polycondensing an alcohol component containing a propylene oxide adduct of bisphenol A and a carboxylic acid component, wherein the propylene oxide adduct of bisphenol A has an average mole of propylene oxide added of from 2.4 to 4.0, and wherein an adduct with 2 mol of propylene oxide is contained in an amount of 60% by mol or less, and an adduct with 4 mol of propylene oxide is contained in an amount of 10% by mol or more, of the propylene oxide adduct of bisphenol A, and wherein the propylene oxide adduct of bisphenol A has a content ratio of primary hydroxyl groups of 10% by mol or less of the entire hydroxyl groups.

Abstract: A toner for electrostatic image development, containing a resin binder containing a polyester having monomer units wherein at least one monomer is selected from the group consisting of fumaric acid and maleic acid, including mixtures thereof; a colorant; and a charge control agent containing a negatively chargeable charge control agent and a positively chargeable charge control agent, wherein the unreacted monomers of fumaric acid, maleic acid or both fumaric acid and maleic acid are contained in the toner in an amount of 0.20% by weight or less. The toner for electrostatic image development of the present invention may be used for the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.

Abstract: A toner for electrostatic image development, containing a resin binder containing a polyester having monomer units wherein at least one monomer is selected from the group consisting of fumaric acid and maleic acid, including mixtures thereof; a colorant; and a charge control agent containing a negatively chargeable charge control agent and a positively chargeable charge control agent, wherein the unreacted monomers of fumaric acid, maleic acid or both fumaric acid and maleic acid are contained in the toner in an amount of 0.20% by weight or less. The toner for electrostatic image development of the present invention may be used for the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.

Abstract: By providing a printing density controller for changing a printing density in a range from a dropout color to non-dropout color, an electrophotographic printing apparatus can conduct the light and shade adjustment of the printing density in a broad range, and also cope with the dropout color printing.

Abstract: When a developing agent prepared to have a preset toner density is loaded in a developing unit, a comparing reference level for controlling the toner density in the developing agent is changed to a value higher than the preset value in the initial stage of operation and fresh toner is supplied to the developing agent so that the toner density of the developing agent is increased in comparison to the reference level. Thereby, the developed density is prevented from decreasing due to an excess amount of friction charge of the toner.