Electrophotographic toner and method of development therewith

Abstract

Cyclo-olefin copolymer resin is contained as a binder resin, and concentration of a charge controlling agent on the surface of the toner is not less than 0.1 mg / toner 1g, and less than 1.0 mg / toner 1g. Furthermore, the toner is held on a non-magnetic sleeve, an electric field is applied between a photoreceptor and the sleeve, and the toner jumps to an electrostatic latent image on the surface of the photoreceptor. In this way, a toner for electrophotography in which image contamination is prevented and deterioration of image density caused by deterioration of jumping property is prevented by maintaining an appropriate amount of charge even in the non-contact developing method using the toner containing cyclo-olefin copolymer resin as a binder resin, can be provided.

Description

technical field [0001] The present invention relates to a toner for electrophotography used in an image forming apparatus such as a copier, a printer, or a facsimile using electrophotography, and a developing method using the toner. Background technique [0002] Dry developers used in the development of image forming devices using electrophotography can be broadly classified into two-component types consisting of toner and carriers containing ferrite powder, iron powder, glass beads, etc. A developer, a magnetic one-component developer in which the toner itself contains magnetic powder, and a non-magnetic one-component developer. The toners used in these developers are mainly composed of binder resins and colorants, and in addition, waxes are added to improve the low-temperature fixability to the recording sheet or the peelability at the fixing member, or to impart Polar (positively charged or negatively charged) charge control agents, etc. The toner is made by mixing thes...

AI Technical Summary

Problems solved by technology

[0011] However, when a toner containing a cycloolefin copolymer resin as a binder resin is used in a non-contact type developing method, charge accumulation tends to occur especially when continuous copying of multiple pages is performed, especially toner on a sleeve under a low-humidity environment. As the thickness of the toner layer becomes larger, the charge of the outer layer of the toner on the sleeve is low, which is prone to image contamination, and the number of contacts between the inner layer and the charged blade increases, and the amount of charge becomes higher, which causes a decrease in leap performance. It can be seen that image density reduction

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