Lubricant for electrophotography, lubricant applying unit, process cartridge, and image forming apparatus

Abstract

An lubricant for electrophotography is applied to a latent image carrier that is supplied with toner having a sphericity of 0.94 or more. The lubricant for electrophotography is added with an inorganic additive having the following relationship:

2Y/1000≦X≦Y/10

where Y is a toner particle size (micrometer), and X is an inorganic additive particle size (micrometer).

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] The present document incorporates by reference the entire contents of Japanese priority document, 2003-414090 filed in Japan on Dec. 12, 2003. BACKGROUND OF THE INVENTION [0002] 1) Field of the Invention [0003] The present invention relates to a lubricant for electrophotography used in an electrostatic duplicating process for development by supplying toner to a latent image carrier that carries a latent image, and to a lubricant applying unit, a process cartridge, and an image forming apparatus. [0004] 2) Description of the Related Art [0005] Electrophotographic color image forming apparatuses are widespread recently, and digitized images are easily available. Under these circumstances, higher definition is required for printed images. Higher resolution and gradation of images are studied, and improvement of toner used to visualize a latent image is also studied. In order to form a high-definition image, it is also studied to obtain a h...

AI Technical Summary

Benefits of technology

[0015] a charging unit that causes a charging member to contact or to be close to the latent image carrier to charge the latent image carrier, a developing unit that deposits toner on a latent image on the latent image carrier to develop the latent image with the toner, and a cleaning unit that cleans the toner remaining on the latent image carrier with a cleaning blade; and a lubricant applying unit that applies a lubricant for electrophotography to the latent image carrier. The lubricant applying unit includes a brush roller that rotates around a rotational axis, and is in contact with the latent image carrier. Toner having a sphericity of equal to or more than 0.94 is supplied to the latent image carrier. An inorganic additive is added to the lubricant, and the inorganic additive satisfies

[0016] An image forming apparatus according to still another aspect of the present invention includes a process cartridge that includes a latent image carrier; at least one of a charging unit that causes a charging member to contact or to be close to the latent image carrier to charge the latent image carrier, a developing unit that deposits toner on a latent image on the latent image carrier to develop the latent image with the toner, and a cleaning unit that cleans the toner remaining on the latent image carrier with a cleaning blade; and a lubricant applying unit that applies a lubricant for electrophotography to the latent image carrier. The lubricant applying unit includes a brush roller that rotates around a rotational axis, and is in contact with the latent image carrier. Toner having a sphericity of equal to or more than 0.94 is supplied to the latent image carrier. An inorganic additive is added to the lubricant, and the inorganic additive satisfies

[0017] An image forming apparatus according to still another aspect of the present invention includes a lubricant applying unit that applies a lubricant for electrophotography to a latent image carrier. The lubricant applying unit includes a brush roller that rotates around a rotational axis, and is in contact with the latent image carrier. Toner having a sphericity of equal to or more than 0.94 is supplied to the latent image carrier. An inorganic additive is added to the lubricant, and the inorganic additive satisfies

Problems solved by technology

Some toner passes under the cleaning blade and remains on the photosensitive element, which may cause an abnormal image such as surface fog to occur.

Thereby, the distribution of the zinc stearate on the photosensitive element becomes uneven, and in a portion with a small amount of the zinc stearate, some of the toner particles pass under the cleaning blade to remain on the photosensitive element.

There is a problem, which is common to the inventions of Japanese Patent Application Laid-Open Publication No.

Hei 11-184340 and 2, such that in an initial stage of use of a new photosensitive element, only a small amount of zinc stearate is present on the photosensitive element, which causes insufficient removal of toner remaining on the photosensitive element.

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