In an example of a method for reducing contamination, a purified imaging oil is formed by filtering an imaging oil through an imaging oil filter, and then filtering the imaging oil through a polar absorbent filter. A surface of an amorphous silicon photoconductor of a liquid electrophotographic printing apparatus is maintained by periodically applying the purified imaging oil to the amorphous silicon photoconductor.

An electrophotographic photosensitive member includes an undercoat layer, a charge generation layer, and a charge transport layer in this order. The undercoat layer contains a cured product of a composition containing an electron transport material, a particle having an average primary particle size of 10 nm or more, and a silicone oil. A content of the particle in the undercoat layer is 3% by mass or more and 20% by mass or less. A content of the silicone oil in the undercoat layer is 0.01% by mass or more and 10% by mass or less relative to the content of the particle.

Described herein is a photoreceptor and a method of making metal oxide particles having hygroscopic polymers attached to a surface of the metal oxide particles. The photoreceptor includes a conductive substrate and an undercoat layer disposed on the conductive substrate. The undercoat layer includes metal oxide particles having hygroscopic polymers attached to a surface of the metal oxide particles. The undercoat layer includes a binder resin. A photosensitive layer is disposed on the undercoat layer.

Described herein is a photoreceptor and a method of making metal oxide particles having hygroscopic polymers attached to a surface of the metal oxide particles. The photoreceptor includes a conductive substrate and an undercoat layer disposed on the conductive substrate. The undercoat layer includes metal oxide particles having hygroscopic polymers attached to a surface of the metal oxide particles. The undercoat layer includes a binder resin. A photosensitive layer is disposed on the undercoat layer.

The present invention provides an electrophotographic photosensitive member which has a substrate, a photoconductive layer and a surface layer formed from hydrogenated amorphous silicon carbide in this order. The average value of the carbon content (C/(C+Si)) of the surface layer formed from the hydrogenated amorphous silicon carbide is set at 0.90 or more and less than 1.00, and the average value of the hydrogen content (H/(H+C+Si)) is set at 0.40 or less; and when the average value of the ratios of the sum of a SiO bond and an OSiO bond in the outermost surface region that constitutes a range within a depth of 5 nm or less from the outermost surface of the surface layer is represented by a, and an average value of the silicon content (Si/(C+Si)) is represented by b, 0.015a*b0.090 holds.

Described herein is a photoreceptor and a method of making metal oxide particles having hygroscopic polymers attached to a surface of the metal oxide particles. The photoreceptor includes a conductive substrate and an undercoat layer disposed on the conductive substrate. The undercoat layer includes metal oxide particles having hygroscopic polymers attached to a surface of the metal oxide particles. The undercoat layer includes a binder resin. A photosensitive layer is disposed on the undercoat layer.

Described herein is a photoreceptor and a method of making metal oxide particles having hygroscopic polymers attached to a surface of the metal oxide particles. The photoreceptor includes a conductive substrate and an undercoat layer disposed on the conductive substrate. The undercoat layer includes metal oxide particles having hygroscopic polymers attached to a surface of the metal oxide particles. The undercoat layer includes a binder resin. A photosensitive layer is disposed on the undercoat layer.

A cylindrical base body of the disclosure includes an outer peripheral surface and an end surface which is connected to the outer peripheral surface. The outer peripheral surface includes a first inclined surface which is inclined inwardly toward the end surface, the end surface includes a second inclined surface which is inclined inwardly toward the outer peripheral surface and is connected to the first inclined surface, and a connecting portion of the first inclined surface and the second inclined surface has a radiused surface.

In an example of a method for reducing contamination, a purified imaging oil is formed by filtering an imaging oil through an imaging oil filter, and then filtering the imaging oil through a polar absorbent filter. A surface of an amorphous silicon photoconductor of a liquid electrophotographic printing apparatus is maintained by periodically applying the purified imaging oil to the amorphous silicon photoconductor.

An image forming apparatus includes a photoconductor, a charging member, a voltage applier, a storage unit, a current detector, a characteristic deriver and a voltage setter. The storage unit stores in advance relationship information representing a relationship between an electrical characteristic of discharge products adhering to the surface and a proper inter-peak voltage value capable of properly charging the surface. The current detector detects a current value of a current flowing from the charging member to the photoconductor. The characteristic deriver derives the electrical characteristic of the discharge products adhering to the surface on the basis of an oscillating voltage applied to the charging member by the voltage applier and the current value. The voltage setter sets the proper inter-peak voltage value corresponding to the electrical characteristic derived by the characteristic deriver in the relationship information as the inter-peak voltage value of the alternating-current voltage.