Toner, developer, toner container, process cartridge, image forming apparatus and image forming method

Abstract

The present invention provides a toner and a developer which includes the toner. The toner is produced in an aqueous medium and includes at least a binding resin, a colorant and a dispersant which disperses the colorant. The binding resin contains 50% by mass to 100% by mass of a polyester resin, and the colorant is a pigment whose surface is given an acid treatment. The acid value of the dispersant is 1 mg KOH / g to 30 mg KOH / g, and the amine value of the dispersant is 1 mg KOH / g to 100 mg KOH / g.

Description

technical field [0001] The present invention relates to a toner for image formation, which has excellent charge properties, fluidity, stability and transfer properties, has good charge properties and good image quality, and can form a toner having excellent OHP optical transparency an image; a developer using the toner; a toner container; a process cartridge; an image forming apparatus; and an image forming method. Background technique [0002] In electrophotographic apparatuses and electrostatic recording apparatuses, an electric latent image or a magnetic latent image is developed by toner. In the electrophotographic method, for example, after an electrostatic image (latent image) is formed, then, the latent image is developed with a toner to form a toner image. For example, a toner image is generally transferred onto a transfer member such as paper, and then fixed by heating. Toners used to develop electrostatic images are generally toner particles including colorants, ...

AI Technical Summary

Problems solved by technology

Therefore, when it is easy to form a wide particle size distribution and produce good resolution and color tone in the abrasive composition particles in the actual reproduced image, it is necessary to remove the fine powder with a size of less than 3 μm and a size greater than 20 μm by classification. micron coarse particles, which detrimentally reduces the yield

Also, in the grinding method, it is difficult to uniformly disperse colorants and charge control agents in thermoplastic resins

In addition, since the colorant added to the toner is exposed on the surface of the toner, there is a problem that the charge distribution on the toner surface is unstable, broadening the charge distribution of the toner and degrading the developing performance

Also, since the toner is prepared simultaneously with the polymerization of the resin, many materials commonly used in toners cannot be used

Although commonly used materials are polymerizable, there are cases where the particle size cannot be sufficiently controlled due to the action of additives such as resins and colorants

Therefore, this method has the problem of having less flexibility in the choice of materials

[0006] In particular, there are problems in that polyester resins generally used in kneading and grinding methods for developing excellent fixing performance and coloring performance cannot be used, and downsizing, acceleration and coloring cannot be satisfied to a satisfactory degree

Therefore, there is also the problem: Insufficient dispersion of colorants reduces OHP transparency

However, because the release agent cannot be refined like a colorant, it is more difficult to add and disperse evenly

There is also a problem: poor dispersion of the release agent suppresses charging performance, developing performance, storage stability and OHP transparency

As described above, toners for electrophotography and related methods capable of satisfying higher performance requirements have not yet been realized.

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