Charging member, process cartridge and electrophotographic apparatus

摘要

Provided a charging member including an electro-conductive substrate and a surface layer. The surface layer includes a binder resin, and a resin particle that roughens the surface layer. A surface of the charging member has a plurality of protrusions each derived from the resin particle. The resin particle has a pore inside thereof, has a porosity Vt of 1.5% by volume or more and 45.0% by volume or less, and has a first and second regions. The first region has a porosity V1, the second region thereof has a porosity V2, and V1 is larger than V2.

主权项

1. A charging member comprising:
an electro-conductive substrate; and a surface layer, wherein: the surface layer comprises
a binder resin, anda resin particle that roughens the surface layer; a surface of the charging member has a plurality of protrusions each derived from the resin particle; the resin particle
has a pore inside thereof,has a porosity Vt of 1.5% by volume or more and 45.0% by volume or less as a whole, and has a first region and a second region, wherein: assuming that the resin particle is a solid particle having no pores, each of the first region and the second region corresponds to a region occupying ½ of a total volume of the solid particle, the first region being located in the resin particle nearest to the electro-conductive substrate, and having a porosity V1 of 2.0% by volume or more and 90.0% by volume or less, the second region being located in the resin particle farthest away from the electro-conductive substrate, and having a porosity V2 of 0.0% by volume or more and 20.0% by volume or less, and wherein: the porosity V1 is larger than the porosity V2.