Abstract: Provided is a photoconductor for electrophotography having high sensitivity, low residual potential, and good wear resistance and contamination resistance, and that is less likely to cause light-induced fatigue and filming, and also exhibits good potential stability before and after repeated printing, even without a surface protective layer formed on a photosensitive layer. Provided also are a process of producing the photoconductor and an electrophotographic apparatus.

Abstract: A toner comprising a toner particle, and strontium titanate, wherein the strontium titanate has a specific number average particle diameter, the strontium titanate has a maximum peak (a) at a diffraction angle (2?) of 32.00 deg to 32.40 deg in CuK? characteristic X-ray diffraction, the half width of the maximum peak (a) is 0.23 deg to 0.50 deg, an intensity (Ia) of the maximum peak (a) and a maximum peak intensity (Ix) in a range of a diffraction angle (2?) of 24.00 deg to 28.00 deg satisfy a specific relationship, the content of strontium oxide and titanium oxide in the strontium titanate is at least 98.0% by mass, and a sum total Et of a rotational torque and a vertical load in powder flowability analysis of the toner is 100 mJ to 2000 mJ.

Abstract: An external toner additive having a resin fine particle containing a crystalline resin and an inorganic fine particle embedded in the resin fine particle, wherein part of the inorganic fine particle is exposed on the surface of the resin fine particle, and in differential scanning calorimetry of the external toner additive, the maximum endothermic peak temperature T1 (° C.) during a first temperature increase and the maximum exothermic peak temperature T2 (° C.) during a first temperature decrease satisfy the formulae (1) to (3) below, with measurement performed between ?40° C. and 150° C. at a rate of increase of 10° C./min during the first temperature increase and between 150° C. and ?40° C. at a rate of decrease in temperature of 10° C./min during the first temperature decrease: T1-T2?40.0??(1) 50.0?T1?120.0??(2) 10.0?T2?80.0??(3).

Abstract: An electrostatic image developing toner includes toner base particles, wherein the toner base particles contain: an amorphous polyester resin; a crystalline resin; and o-acetoacetaniside, and the content of the o-acetoacetaniside in the toner base particles is 0.1 ppm by mass or more and 200 ppm by mass or less.

Abstract: A toner for electrostatic image development includes: toner base particles containing at least a nonionic surfactant, a binder resin, and a release agent; and an external additive. The content of the nonionic surfactant is from 0.05% by mass to 1% by mass inclusive based on the total mass of the toner, and the external additive contains particles with an arithmetic mean particle diameter of from 50 nm to 400 nm inclusive. The amount of the external additive released is 5% by mass or less.

Abstract: An electrostatic image developing toner includes toner base particles including at least a binder resin and a release agent, wherein the binder resin includes a hybrid resin having a polyester resin segment and a styrene-acrylic copolymer segment, and a molecular weight distribution curve of the toner satisfies Formula (1): 1.3?b/a?2.5, where, in the molecular weight distribution curve in which a perpendicular line is drawn from a baseline to a peak top having a peak top height to divide the molecular weight distribution curve into a lower-molecular-weight region and a higher-molecular-weight region, a represents a width of the lower-molecular-weight region at a height of 15% of the peak top height, and b represents a width of the higher-molecular-weight region at a height of 15% of the peak top height.

Abstract: A toner for electrostatic image development includes: toner base particles containing at least a nonionic surfactant, a binder resin, and a release agent; and an external additive. The content of the nonionic surfactant is from 0.05% by mass to 1% by mass inclusive based on the total mass of the toner. The external additive contains inorganic particles having an arithmetic mean particle diameter of from 50 nm to 400 nm inclusive and an average circularity of from 0.5 to 0.8 inclusive.

Abstract: The present invention relates to an electrostatic charge image developing toner, wherein when a tan ? measurement is performed twice by a rheometer, in the first measurement, a tan ? value measured at 130° C. is set as TP1 (130° C.), and a tan ? value measured at 140° C. is set as TP1 (140° C.), in the second measurement, a tan ? value measured at 140° C. is set as TP2 (140° C.), TP2 (140° C.)/TP1(140° C.) is equal to or smaller than 0.95, and TP1 (130° C.) is equal to or greater than 2.5.

Abstract: A toner and a toner process including providing at least one hybrid metallic toner component selected from the group consisting of hybrid metallic-latex particles, hybrid metallic-wax particles, hybrid metallic-colorant particles, and combinations thereof; contacting the at least one hybrid metallic toner component with one or more components selected from the group consisting of a latex polymer, a wax; and a colorant to form a blend; heating the blend at a temperature below the glass transition temperature of the latex polymer to form aggregated toner particles; adding a coalescing agent to the toner particles thereby coalescing the toner particles; and recovering the toner particles.

Abstract: An electrostatic charge image developing toner has a surface property index value represented by Formula S of 2.0 to 2.8, an electrostatic charge image developing toner has a surface property index value represented by Formula S of more than 2.8 and 3.5 or less, and an electrostatic charge image developing toner has a surface property index value represented by Formula S of more than 1.0 and less than 2.0 and a calculated value of a specific surface area in Formula S of 0.70 to 1.3: (Surface property index value)=(Measured value of specific surface area)/(Calculated value of specific surface area)??Formula S wherein (Calculated value of specific surface area)=(Sum of surface areas calculated from equivalent circle diameters of 4,500 toner particles in flow particle image analysis)/{(Specific gravity of toner)×(Sum of volumes calculated from equivalent circle diameters of 4,500 toner particles in flow particle image analysis)}.

Abstract: A white toner for electrostatic image development includes toner particles containing a binder resin, which contains at least a crystalline polyester resin and an amorphous polyester resin, and a white pigment. The loss tangent tan ? at 30° C. determined by dynamic viscoelasticity measurement is 0.2 or more and 1.0 or less.

Abstract: An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer disposed on the conductive substrate.

Abstract: An image forming apparatus includes an image bearing member and a static elimination device. The static elimination device irradiates static elimination light onto a circumferential surface of the image bearing member. The image bearing member includes a conductive substrate and a single-layer photosensitive layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The static elimination light has a wavelength of at least 600 nm and no greater than 800 nm. The photosensitive layer has an optical absorption coefficient of at least 600 cm?1 and no greater than 1,500 cm?1 with respect to light having a wavelength of 660 nm.

Abstract: A carrier core material formed with ferrite particles, the skewness Rsk of the particle is equal to or more than ?0.40 but equal to or less than ?0.20, and the kurtosis Rku of the particle is equal to or more than 3.20 but equal to or less than 3.50. Here, the maximum height Rz of the particle is equal to or more than 2.20 ?m but equal to or less than 3.50 ?m. Moreover, the ferrite particle contains at least either of Mn and Mg elements. In this way, cracking or chipping in a concave-convex portion of a particle surface is unlikely to occur, and moreover, the amount of coating resin used can be reduced without properties such as electrical resistance being lowered.

Abstract: A brilliant toner includes a first toner which contains a first toner particle containing a flake-shape brilliant pigment; and a second toner which contains a second toner particle containing a flake-shape brilliant pigment, and has a different color from that of the first toner, and an electrostatic charge image developing toner includes a first toner which contains a first toner particle; and a second toner which has a different color from that of the first toner, and contains the second toner particle, in which, based on a charge distribution of each of the first toner and the second toner obtained according to a charge spectrograph method, maximum peak positions of the first toner and the second toner are taken as P1 and P2, respectively, and full widths at half maximum of the first toner and the second toner are taken as W1 and W2, respectively, |P1?P2| is 3 mm or less, and |W1?W2| is 3 mm or less.

Abstract: There are provided a polyester resin for toner which has a sufficiently low TVOC, can be produced with high productivity, and can produce toner having excellent durability; and toner containing the polyester resin for toner. The polyester resin for toner has a TVOC of 380 ppm or less and includes a component derived from ethylene glycol, a hydrocarbon group having 12 carbon atoms or more, and a titanium element.

Abstract: An improved organic photoconductor drum having a protective overcoat layer and method to make the same is provided. The protective overcoat layer is prepared from a curable composition including nano metal oxide particles sized less than 400 nm in combination with an urethane acrylate resin having at least 6 functional groups.

Abstract: An electrophotographic photoreceptor includes a cylindrical substrate; and a surface layer located on an outer surface of the cylindrical substrate. At least a substrate central portion in a cylindrical axial direction of the outer surface of the cylindrical substrate is formed as a rough surface, and a surface roughness of a surface-layer central portion in the cylindrical axial direction of an outer surface of the surface layer is larger than that of at least one of two surface-layer end portions in the cylindrical axial direction of the outer surface of the surface layer. An image forming apparatus includes the electrophotographic photoreceptor; and a peripheral member capable of contacting a surface of the electrophotographic photoreceptor.

Abstract: A pigment dispersion has low viscosity and good dispersion property without depending on pigment species. The pigment dispersion contains a dispersion medium, an organic pigment, and a triazo compound having a specific structure.

Abstract: A toner comprising a toner particle that contains a toner base particle and an organosilicon polymer on a surface of the toner base particle, wherein the organosilicon polymer forms protruded portions with a prescribed structure on the surface of the toner base particle, and in the toner cross section, when the protrusion width w is the length of the segment where a protruded portion and the toner base particle form a continuous interface, the protrusion diameter D is the maximum length of a protruded portion, and the protrusion height H is the length from the peak of the protruded portion to the line along the circumference of the toner base particle surface, the numerical proportion of these protruded portions having a ratio D/w of the protrusion diameter D to the protrusion width w from 0.33 to 0.80, is a least 70 number %.