Abstract: An electrophotographic apparatus having an electrophotographic photosensitive member, a charging unit, and a developing unit for forming a toner image on a surface of the electrophotographic photosensitive member, wherein the charging unit has a conductive member disposed to be contactable with the electrophotographic photosensitive member; a conductive layer at the surface of the conductive member has a matrix and a plurality of domains dispersed in the matrix; at least a portion of the domains is exposed at the outer surface of the conductive member; the outer surface of the conductive member is constituted of at least the matrix and the domains; a volume resistivity R1 of the matrix is greater than 1.00×1012 ?·cm; a volume resistivity R2 of the domains is smaller than R1; the developing unit contains the toner; and a dielectric loss tangent of the toner is at least 0.0027.

Abstract: A toner comprising: a toner particle that contains a binder resin and a colorant: and an external additive, wherein (1) the average circularity of the toner is at least 0.960; (2) the fixing ratio of the external additive on the toner particle is from 75% to 100%; and (3) in a differential curve obtained by the differentiation, by load, of a load-displacement curve where the horizontal axis is load (mN) and the vertical axis is displacement (?m), the load-displacement curve being provided by measurement of the strength of the toner by a nanoindentation procedure, a load A that provides a maximum value in the differential curve in a load region from 0.20 mN to 2.30 mN is from 1.15 mN to 1.50 mN.

Abstract: Provided is a toner containing a toner particle including a binder resin, a wax, and a colorant. The softening point of the toner is at least 80° C. and not more than 140° C. The average circularity of the toner is at least 0.940. The integrated value of stress in the toner at 150° C. which is measured by using a tackiness tester is at least 78 g·m/sec.

Abstract: A toner comprising a toner particle including a binder resin and a colorant and an external additive, wherein the external additive contains an external additive A having a Feret diameter of 60 to 200 nm, the external additive A is inorganic fine particles or organic-inorganic composite fine particles, adhesion index of the external additive A to the toner is 0.00 to 3.00, and penetration depth b and protrusion height c satisfy Relational expressions (1) and (2) below, where b (nm) denotes penetration depth of the external additive A, at a portion of the external additive A penetrating into the toner particle interior from the surface thereof, and c (nm) denotes a protrusion height of the external additive A at that portion, in an observation of an image resulting from image processing of a cross section of the toner using TEM; 60?b+c?200??(1), 0.15?b/(b+c)?0.30??(2).

Abstract: A toner comprising a toner particle that contains a binder resin and a colorant, wherein (1) an average circularity of the toner is at least 0.960, (2) an onset temperature T? (° C.) of a storage elastic modulus E? of the toner, as determined by a powder dynamic viscoelastic measurement, is from 50° C. to 70° C., and (3) in a differential curve obtained by differentiation, by load, of a load-displacement curve provided by measurement of the strength of the toner by a nanoindentation procedure, with the horizontal axis being load (mN) and the vertical axis being displacement (?m), the load X that provides the maximum value in the differential curve in the load region from 0.20 mN to 2.30 mN is from 1.00 mN to 1.50 mN.

Abstract: The toner has a toner particle that contains a binder resin, a colorant, a release agent, and a crystalline polyester, wherein the release agent contains an ester wax, and the peak top temperature of the maximum endothermic peak of the ester wax as measured with a differential scanning calorimeter is from 65° C. to 85° C., the ester wax satisfies specific conditions and the crystalline polyester satisfies specific conditions, the toner contains from 3.0 parts by mass to 20.0 parts by mass of the crystalline polyester per 100 parts by mass of the binder resin, and the mass ratio of the ester wax to crystalline polyester is from 25/75 to 75/25.

Abstract: Provided is a toner containing a toner particle including a binder resin, a wax, and a colorant. The softening point of the toner is at least 80° C. and not more than 140° C. The average circularity of the toner is at least 0.940. The integrated value of stress in the toner at 150° C. which is measured by using a tackiness tester is at least 78 g·m/sec.

Abstract: Provided is a toner containing a toner particle including a binder resin, a wax, and a colorant. The softening point of the toner is at least 80° C. and not more than 140° C. The average circularity of the toner is at least 0.940. The integrated value of stress in the toner at 150° C. which is measured by using a tackiness tester is at least 78 g·m/sec.

Abstract: A toner comprising a toner particle that contains a binder resin and a colorant, wherein (1) an average circularity of the toner is at least 0.960, (2) an onset temperature T? (° C.) of a storage elastic modulus E? of the toner, as determined by a powder dynamic viscoelastic measurement, is from 50° C. to 70° C., and (3) in a differential curve obtained by differentiation, by load, of a load-displacement curve provided by measurement of the strength of the toner by a nanoindentation procedure, with the horizontal axis being load (mN) and the vertical axis being displacement (?m), the load X that provides the maximum value in the differential curve in the load region from 0.20 mN to 2.30 mN is from 1.00 mN to 1.50 mN.

Abstract: A toner comprising: a toner particle that contains a binder resin and a colorant: and an external additive, wherein (1) the average circularity of the toner is at least 0.960; (2) the fixing ratio of the external additive on the toner particle is from 75% to 100%; and (3) in a differential curve obtained by the differentiation, by load, of a load-displacement curve where the horizontal axis is load (mN) and the vertical axis is displacement (?m), the load-displacement curve being provided by measurement of the strength of the toner by a nanoindentation procedure, a load A that provides a maximum value in the differential curve in a load region from 0.20 mN to 2.30 mN is from 1.15 mN to 1.50 mN.

Abstract: Provided is a toner including a binder resin, a colorant, a crystalline polyester, and a release agent, wherein a cross-sectional image of the toner is observed using a scanning transmission electron microscope, domains of the crystalline polyester are present in the cross-sectional image of the toner, the domains have a number-average major diameter of at least 50 nm and not more than 300 nm, the number of the domains is at least 8 and not more than 500, and the domains are present at least 60 number % and not more than 100 number % from an outline of the cross-sectional image to 25% of the distance between the outline and the centroid of the cross-sectional image.

Abstract: Provided is a toner, including: a toner particle containing a binder resin and a colorant; and an inorganic fine particle, in which the toner particle has an average circularity of 0.960 or more, and in which the toner satisfies the formula (1) and the formula (2). Fp(A)?25.0 nN??Formula (1) (Fp(B)?Fp(A))/Fp(A)?0.

Abstract: Provided is a toner having a toner particle that contains a binder resin, a colorant, a wax, and a crystalline polyester, wherein two or more peak tops for crystallization peaks are present in a temperature range from 40° C. to 80° C. in a first DSC curve obtained by a process or cooling the toner from 100° C. to 20° C. at 0.5° C./min, and using ?H(0.5) for the exothermic quantity for the peak on the lowest temperature side of these crystallization peaks and using ?H(100) for the exothermic quantity of the crystallization peak on the lowest temperature side in a second DSC curve obtained by a process of cooling the toner from 100° C. to 20° C. at 100° C./min, the ratio [?H(100)/?H(0.5)] is at least 2.0 and not more than 6.0.

Abstract: Provided is a method for producing a toner, the method including a treatment process of treating a coloring particle including a binder resin, a colorant, a crystalline polyester, and a wax in an aqueous medium, wherein, the peak temperature of a crystallization peak (Pp) in the crystalline polyester is denoted by Tp (° C.) and the peak temperature of a crystallization peak (Pw) in the wax is denoted by Tw (° C.), the Tp and Tw satisfy a specific relationship, and the treatment process has a specific cooling step.

Abstract: Provided is a method for producing a toner, the method including a treatment process of treating a coloring particle including a binder resin, a colorant, a crystalline polyester, and a wax in an aqueous medium, wherein, the peak temperature of a crystallization peak (Pp) in the crystalline polyester is denoted by Tp (° C.) and the peak temperature of a crystallization peak (Pw) in the wax is denoted by Tw (° C.), the Tp and Tw satisfy a specific relationship, and the treatment process has a specific cooling step.

Abstract: Provided is a toner including a binder resin, a colorant, a crystalline polyester, and a release agent, wherein a cross-sectional image of the toner is observed using a scanning transmission electron microscope, domains of the crystalline polyester are present in the cross-sectional image of the toner, the domains have a number-average major diameter of at least 50 nm and not more than 300 nm, the number of the domains is at least 8 and not more than 500, and the domains are present at at least 60 number % and not more than 100 number % from an outline of the cross-sectional image to 25% of the distance between the outline and the centroid of the cross-sectional image.

Abstract: Provided is a toner having a toner particle that contains a binder resin, a colorant, a wax, and a crystalline polyester, wherein two or more peak tops for crystallization peaks are present in a temperature range from 40° C. to 80° C. in a first DSC curve obtained by a process or cooling the toner from 100° C. to 20° C. at 0.5° C./min, and using ?H(0.5) for the exothermic quantity for the peak on the lowest temperature side of these crystallization peaks and using ?H(100) for the exothermic quantity of the crystallization peak on the lowest temperature side in a second DSC curve obtained by a process of cooling the toner from 100° C. to 20° C. at 100° C./min, the ratio [?H(100)/?H(0.5)] is at least 2.0 and not more than 6.0.

Abstract: Provided is a toner containing a toner particle including a binder resin, a wax, and a colorant. The softening point of the toner is at least 80° C. and not more than 140° C. The average circularity of the toner is at least 0.940. The integrated value of stress in the toner at 150° C. which is measured by using a tackiness tester is at least 78 g·m/sec.

Abstract: Provided is toner comprising toner particle containing binder resin and colorant and silica fine particle, wherein: the silica fine particle contains silica fine particle A and silica fine particle B; silica fine particle A has a number average particle diameter of primary particle of 5 nm or more and 20 nm or less; silica fine particle B has a number average particle diameter of primary particle of 80 nm or more and 200 nm or less; and silica fine particle B has a half width of a peak of primary particle of 25 nm or less, in a weight-based particle size distribution, and wherein when the toner is measured by adhesive force-measuring method by using polycarbonate thin film, an adhesion of the silica fine particle A is 0.5% by area or less relative to 100% by area of the total area of the polycarbonate thin film.

Abstract: A magnetic toner including: magnetic toner particles containing a binder resin, a magnetic body, and a release agent; and inorganic fine particles present on the surface of the magnetic toner particles, wherein the inorganic fine particles present on the surface of the magnetic toner particles contain metal oxide fine particles, the metal oxide fine particles containing silica fine particles, and optionally containing titania fine particles and alumina fine particles, and a content of the silica fine particles being at least 85 mass % with respect to a total mass of the silica fine particles, the titania fine particles and the alumina fine particles, wherein the magnetic toner has a coverage ratio A of the magnetic toner particles' surface by the inorganic fine particles and a coverage ratio B of the magnetic toner particles' surface by the inorganic fine particles fixed to the magnetic toner particles' surface that reside in prescribed numerical value ranges; the binder resin contains a styrene resin; the re