An electrographic toner can include toner particles having a multi-particulate additive disposed on an exterior surface of the toner particles. The toner particles can have a specific surface area from 3.0 m.sup.2/g to 3.65 m.sup.2/g and can include a binder resin, a colorant, and a releasing compound. The multi-particulate additive can include aluminum oxide particles, small sol-gel silica particles having a particle size distribution from 20 nm to 50 nm, large sol-gel silica particles having a particle size distribution from 90 nm to 130 nm, and fumed silica particles surface-treated with polydimethylsiloxane (PDMS).

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.

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.

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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):

A toner comprising: a toner particle comprising a binder resin and an ester wax; and an external additive, wherein the binder resin comprises a polyester resin comprising a dodecenylsuccinic acid unit, a molecular weight of the ester wax is at least 650, the external additive comprises a needle-shaped inorganic particle, a number-average value of minor diameter of the needle-shaped inorganic particle is at least 10 nm, a number-average value of aspect ratio of the needle-shaped inorganic particle is at least 5, and X and Y satisfy the following Formula (1), where X (mass %) is a content of the dodecenylsuccinic acid unit based on a mass of the toner particle and Y (mass %) is a content of the ester wax based on the mass of the toner particle,

[00001]$\begin{array}{cc}0.25Y/X4.00.& \left(1\right)\end{array}$

An image forming apparatus includes a rotatable image bearing member, a charging member, a developing unit, a cleaning member, and a supply container. In an accommodating portion of a new developing unit, an initial developer which is a developer in a predetermined amount is filled in advance. The initial developer contains toner particles of which charge polarity is a predetermined polarity, and to the toner particles of the initial developer, lubricant particles of a polarity opposite in charge polarity to the predetermined polarity are externally added. A supply developer which is the developer accommodated in the supply container contains the toner particles. An external addition amount of the lubricant particles to the toner particles in the supply developer is smaller than an external addition amount of the lubricant particles to the toner particles in the initial developer.

Used is an image forming apparatus including an image carrier and a developer carrier, in which a toner particle of the developer includes convex portions on a surface of a toner base particle, in a horizontal image converted from a cross-sectional image of the toner particle with STEM, when a convex maximum length D and a convex height H are equal to each other, and convex portions having a convex height H of 20 nm or more are defined as convex portions Y, a number-based average of convex widths W in the convex portions Y is at least 40 nm and not more than 200 nm, when a width of the horizontal image is defined as a circumferential length L, and a total of the convex widths W of the convex portions Y is indicated by W, W/L is 0.5 or more.