Canon Kabushiki Kaisha

Tsuyoshi Shimada

Kumiko Takizawa

Ikuyo Kuroiwa

Wataru Kitamura

Kan Tanabe

Haruhiko Mitsuda

Eileen Takeuchi

Takanori Ueno

Tatsuya Ikezue

Koji Takahashi

Mai Murakami

Ryoichi Tokimitsu

Naoaki Ichihashi

Provided is an electrophotographic photosensitive member in which the generation of a positive ghost image is suppressed under a low-temperature and low-humidity environment, and the occurrence of cracking is suppressed under a high-temperature and high-humidity environment. Also provided are a process cartridge mounted with the electrophotographic photosensitive member, and an electrophotographic apparatus including the process cartridge. The electrophotographic photosensitive member of the present disclosure is characterized in that an undercoat layer contains aluminum oxide particles and titanium oxide particles at a specific mass ratio.

Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus

An electrophotographic photosensitive member includes a support, an undercoat layer, a photosensitive layer, and a surface layer, the undercoat layer containing a binder resin and strontium titanate particles, the surface layer being a cured film of a composition containing at least one compound selected from a guanamine compound and a melamine compound, and a charge transport material having at least one substituent selected from &#x2014;OH, &#x2014;OCH, &#x2014;NH, &#x2014;SH, and &#x2014;COOH.

Provided is an electrophotographic photosensitive member that can achieve both of abrasion resistance and the suppression of a ghost. The electrophotographic photosensitive member includes: a support; an undercoat layer; a charge-generating layer; and a charge-transporting layer, the undercoat layer, the charge-generating layer, and the charge-transporting layer being arranged in the stated order on the support, wherein the charge-transporting layer includes a charge-transporting substance, and a polymer containing a structure represented by the following general formula (1) and a structure represented by the following general formula (2), wherein the charge-generating layer includes a phthalocyanine crystal and a binder resin, and wherein the undercoat layer includes strontium titanate particles and a binder resin. 

An electrophotographic photoconductor includes, in sequence, a support member; an undercoating layer containing a binder resin and an inorganic particle; and a photosensitive layer, wherein the binder resin of the undercoating layer is an alkyd-melamine resin, and the inorganic particle of the undercoating layer contains a strontium titanate particle.

Electrophotographic photoconductor, process cartridge, and electrophotographic apparatus

The electrophotographic photosensitive member includes an undercoat layer and a surface layer on or above a support in this order, in which the undercoat layer contains metal oxide particles and a specific binder resin, the surface layer contains a charge transporting substance, fluororesin particles, and a specific binder resin, an arithmetic average roughness Ra of a surface of the undercoat layer is 0.15 &#x3bc;m or less, a refractive index (a) of the metal oxide particles and a refractive index (b) of the binder resin contained in the undercoat layer satisfy a specific relationship, and a refractive index (c) of the binder resin contained in the surface layer and a refractive index (d) of the fluororesin particles satisfy a specific relationship.

An electrophotographic apparatus includes an electrophotographic photosensitive member, a charging roller disposed so as to come into contact with the electrophotographic photosensitive member, and a charging device operable to apply only a DC voltage to charge the electrophotographic photosensitive member. The electrophotographic photosensitive member includes a support member, an undercoat layer over the support member, and a photosensitive layer over the undercoat layer and having a plurality of discrete recesses in the surface thereof. The undercoat layer contains zinc oxide particles and a binder resin. The undercoat layer has cavities therein, and the cavities account for 5.00% or less of the volume of the undercoat layer.

Electrophotographic apparatus

Provided is an electrophotographic photosensitive member that can suppress the generation of both an interference fringe and a streaky uneven part in a circumferential direction on an image. The generation of the interference fringe and the generation of the streaky uneven part in the circumferential direction on the image are suppressed by defining a length of a line-shaped groove of a support in a circumferential direction, and defining roughness parameters of a support in an axial direction.

Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus

There is provided an electrophotographic photosensitive member, a process cartridge and an electrophotographic apparatus in which residual potential is suppressed and a ghost image is prevented from being generated in a low-humidity environment in an undercoat layer of the electrophotographic photosensitive member. An electrophotographic photosensitive member including: an undercoat layer containing a strontium titanate particle having a maximum peak at a position of 2&#x3b8;=32.20&#xb1;0.20 (&#x3b8; represents a Bragg angle) in a CuK&#x3b1; characteristic X-ray diffraction pattern and a half-value width of the maximum peak of 0.10 deg or more and 0.50 deg or less, and a titanium oxide particle; and a photosensitive layer containing a polyvinyl butyral resin, and a process cartridge and an electrophotographic apparatus each provided with the electrophotographic photosensitive member.

There is provided an electrophotographic photosensitive member in which the variation in potential during repeated use is reduced. The electrophotographic photosensitive member is the electrophotographic photosensitive member of which an undercoat layer comprises a urethane resin and titanium oxide particles whose primary particle and secondary particle diameters are defined.

There is provided an electrophotographic photosensitive member, a process cartridge and an electrophotographic apparatus that are excellent in charging properties and can suppress residual potential in the case where a strontium titanate particle is used as a metal oxide particle in an undercoat layer of the electrophotographic photosensitive member. An electrophotographic photosensitive member in which an undercoat layer contains a strontium titanate particle having a maximum peak at a position of 2&#x3b8;=32.20&#xb1;0.20 (&#x3b8; represents a Bragg angle) in a CuK&#x3b1; characteristic X-ray diffraction pattern, the maximum peak having a half-value width of 0.10 deg or more and 0.50 deg or less, and a process cartridge and an electrophotographic apparatus each provided with the electrophotographic photosensitive member.

The present invention provides an electrophotographic apparatus in which the deterioration of electrical properties in repetitive use is suppressed even in the case where an electrophotographic photosensitive member absorbs moisture under a high-temperature and high-humidity environment. An undercoat layer of the electrophotographic photosensitive member provided in the electrophotographic apparatus contains (&#x3b1;) a metal oxide particle, (&#x3b2;) a particular benzophenone compound and (&#x3b3;) a compound represented by the following formula (2). wherein Rto Reach independently represent a hydrogen atom, a hydroxy group, a halogen atom, an alkyl group, an alkoxy group or an amino group and Arepresents an alkenyl group having 2 or more and 4 or less carbon atoms.

The present invention provides an electrophotographic photosensitive member including a support, and a photosensitive layer on the support. The photosensitive layer has a charge generating layer containing a charge generating material and a charge transporting layer containing a charge transporting material, in this order. The charge transporting layer contains (&#x3b1;) a specific polycarbonate resin or a specific polyester resin, (&#x3b2;) the charge transporting material, (&#x3b3;) a methoxybenzene, and (&#x3b4;) a methoxybenzene, a methoxycyclohexane or a methylhexanol having a substituent. The content W&#x3b4; of the (&#x3b4;) is 0.001% by mass or more and 1% by mass or less based on the total mass of the charge transporting layer.

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Kashiwa, Japan

Tsuyoshi Shimada