An electrostatic charge image developing carrier contains magnetic particles and a resin coating layer on a surface of the magnetic particles, in which inorganic particles are provided on a surface of the electrostatic charge image developing carrier or contained in the resin coating layer, the inorganic particles contains Ti and any of Ca, Sr, or Ba, an average circularity of primary particles of the inorganic particles is 0.82 or more and 0.94 or less, and a BET specific surface area of the magnetic particles is 0.12 m.sup.2/g or more and 0.24 m.sup.2/g or less.

Provided is an electrophotographic apparatus in which the occurrence of image density unevenness (pattern memory) at the time of repeated use under a high-temperature and high-humidity environment is suppressed. The electrophotographic apparatus is an electrophotographic apparatus including: an electrophotographic photosensitive member; and a developing unit, which includes a toner, and which is configured to develop an electrostatic latent image with the toner to form a toner image on a surface of the electrophotographic photosensitive member, wherein the electrophotographic photosensitive member includes a surface layer containing a compound represented by the formula (1), a binder resin, and silicone resin particles, and wherein the toner includes toner particles each containing a polyester resin having a polyethylene terephthalate segment.

A process cartridge has a developing roller, a photosensitive drum, and the frame having a first frame rotatably supporting the developing roller and a second frame rotatably supporting the photosensitive drum. The first frame is movable relative to the second frame between a first position and a second position. The developing roller and the photosensitive drum are in contact at the first position and separated at the second position. A developing roller coupling member, a chip having an electrical contact surface and a separation protrusion with a force receiving surface at the lower end of the frame to receive a force to move the first frame from the first position to the second position. When the first frame is in the first position, a lower end of the force receiving surface is not lower than a lower end of the covering portion.

An electrophotographic photoreceptor includes: a conductive substrate; and a multilayer-type photosensitive layer that is disposed on the conductive substrate and has a charge generation layer and a charge transport layer. The charge transport layer contains a charge-transporting material and a polyester resin (1) having a dicarboxylic acid unit (A) represented by formula (A) and a diol unit (B) represented by formula (B). The polyester resin (1) contained in the charge transport layer satisfies 50,000Mw200,000 and 4.0<Mw/Mn<6.0, wherein Mw is a weight average molecular weight of the polyester resin (1), and Mn is a number average molecular weight of the polyester resin (1).

##STR00001##

In formula (A), Ar.sup.A1 and Ar.sup.A2 are each independently an optionally substituted aromatic ring, L.sup.A is a single bond or a divalent linking group, and n.sup.A1 is 0, 1, or 2. In formula (B), Ar.sup.B1 and Ar.sup.B2 are each independently an optionally substituted aromatic ring, L.sup.B is a single bond, an oxygen atom, a sulfur atom, or C(Rb.sup.1)(Rb.sup.2), and n.sup.B1 is 0, 1, or 2, and Rb.sup.1 and Rb.sup.2 are each independently a hydrogen atom, a C1-C20 alkyl group, a C6-C12 aryl group, or a C7-C20 aralkyl group, and Rb.sup.1 and Rb.sup.2 taken together may form a cyclic alkyl group.

An electrophotographic photoreceptor includes: a conductive substrate; and a photosensitive layer. The photosensitive layer includes a polyarylate resin, a hole transporting agent, and an antioxidant. The polyarylate resin has a repeating unit represented by the following formula (1) and a repeating unit represented by the following formula (2). The antioxidant is a compound represented by the following formula (AOX1).

##STR00001## In the formula (1), R.sup.1 and R.sup.2 each independently represent a hydrogen atom or a methyl group and t represents an integer of 1 or more and 3 or less.

##STR00002## In the formula (2), R.sup.3 represents a divalent group represented by the following formula (X1), (X2), or (X3).

##STR00003##

An electrostatic charge image developing toner contains toner particles containing a resin and a colorant, in which, in the toner particles, in a case where a Net intensity of a Br element measured by X-ray fluorescence analysis is denoted by IBr and a Net intensity of an S element measured by X-ray fluorescence analysis is denoted by IS, IBr is 1 kcps or more and 30 kcps or less, and IS/IBr is 0.005 or more and 1.2 or less.

An electrostatic charge image developing toner contains toner particles that contain an amorphous polyester resin and a crystalline resin as a binder resin, in which the toner particles contain, as the amorphous polyester resin, an amorphous polyester resin (S) that has at least one of a constitutional unit derived from an aliphatic dicarboxylic acid represented by Structural formula (A) or a constitutional unit derived from an aliphatic diol represented by Structural formula (B), a proportion of a total of the constitutional unit derived from the aliphatic dicarboxylic acid represented by Structural formula (A) and the constitutional unit derived from the aliphatic diol represented by Structural formula (B) with respect to all constitutional units constituting the amorphous polyester resin is 0.5% or more and 10.0% or less in terms of molar ratio, and in a dynamic viscoelasticity measurement of the toner particles in a case where a temperature is raised from 30 C. to 120 C., a minimal value tan (min) of a loss tangent is present at 50 C. or higher and 80 C. or lower and is 0.50 or more and 1.00 or less.

##STR00001##

In Structural formulae (A) and (B), nA and nB each independently represent an integer of 2 or more and 12 or less.

An electrostatic charge image developing toner contains toner particles that contains an amorphous resin and a crystalline resin as a binder resin, and an external additive, in which the external additive contains inorganic particles having a specific gravity of 1.3 or more and 2.0 or less, and in a dynamic viscoelasticity measurement of the toner particles in a case where a temperature is decreased from 110 C. to 30 C., a ratio tan (80)/tan (60) of a loss tangent tan (80) at a temperature of 80 C. to a loss tangent tan (60) at a temperature of 60 C. is 0.90 or more and 1.40 or less, and the loss tangent tan (80) at a temperature of 80 C. is 1.20 or more and 1.70 or less.

To provide an electrophotographic apparatus and a process cartridge each suppressing the occurrence of image smearing in an output image under a high-temperature and high-humidity environment, provided are the following electrophotographic apparatus and process cartridge. That is, provided are an electrophotographic apparatus including: an electrophotographic photosensitive member; a charging unit; an image exposing unit; a developing unit; and a transferring unit, wherein the electrophotographic photosensitive member includes a surface layer containing indium tin oxide particles and a (meth)acrylic resin, and wherein the toner contains strontium titanate particles as an external additive, and a process cartridge.

An electrostatic charge image developing toner contains toner particles that contain an amorphous polyester resin and a crystalline polyester resin as a binder resin and internally-added crosslinked resin particles, in which the internally-added crosslinked resin particles are styrene-(meth)acrylic copolymer particles in which a storage elastic modulus G in a range of 60 C. or higher and 100 C. or lower is 110.sup.5 Pa or more and 110.sup.6 Pa or less, an average dispersion size of the internally-added crosslinked resin particles is 100 nm or more and 300 nm or less, and in a case where a square region of 3 m3 m having a size of 600 pix600 pix in a cross-sectional observation of the toner particles is divided into nn regions, in the nn divided regions, the following expression (1) is satisfied from DAR(n) that is a coefficient of variation of an area ratio of the internally-added crosslinked resin particles to an area of the divided regions and slope F(16) that is a slope of an approximate straight line in a dispersion diagram obtained by changing the n to 3, 4, 6, 8, 12, and 16 and plotting log [1/n] on an X-axis and log [DAR(n)] on a Y-axis.

0.6slope F(16)Expression (1):