A magnetic carrier comprising a magnetic carrier core and a resin coating layer formed on the surface of the magnetic carrier core, wherein the resin coating layer includes a polymer having a structure represented by the following formula (1), and a content ratio of the structure represented by the formula (1) is from 5% by mass to 95% by mass based on a resin component of the resin coating layer, ##STR00001##
wherein, R.sup.1 is H or CH.sub.3, and X is a structure represented by the following formula (2):
(C.sub.mH.sub.2m)R.sup.2(C.sub.nH.sub.2n)OH(2)
wherein, R.sup.2 is a hydrocarbon group being a cyclic structure having 4 to 8 carbon atoms, and m and n are integers of 0 to 4.

A toner has a toner particle including a binder resin, a colorant, and a wax, in which in a cross section of the toner particle observed under a scanning transmission electron microscope, a proportion of the number of toner particles having a void with a long diameter of 0.50 m or less is 60 number % or more, and a proportion of the number of toner particles having a void in a region from an outline of the cross section of the toner particle inward to 1.00 m in a total number of the toner particles having a void is 30 number % or less.

A toner comprising a toner particle including a binder resin and a magnetic body, wherein in cross-sectional observation of the toner with a transmission electron microscope, where an area percentage occupied by the magnetic body in a region of 200 nm or less from a contour of a cross section of the toner particle to a centroid of the cross section is taken as A1, and an area percentage occupied by the magnetic body in a region of from 200 nm to 400 nm from the contour of the cross section of the toner particle to the centroid of the cross section is taken as A2, the area percentage A1 is from 38% to 85%, the area percentage A2 is from 0% to 37%, and a ratio A2/A1 of the area percentage A2 to the area percentage A1 is from 0 to 0.75.

A toner comprising a toner particle including a binder resin, wherein the toner is such that (1) when a powder dynamic viscoelasticity measurement method is used, a measurement start temperature is set to 25 C., and a ramp rate is set to 20 C./min, on a curve of a storage elastic modulus E (Pa) where a temperature ( C.) is plotted against an abscissa and the storage elastic modulus E is plotted against an ordinate, a temperature at a time when the E at a start of a measurement has decreased by 50% is from 60 C. to 90 C., and (2) a load at a yield point of a displacement-load curve which is determined by a nanoindentation method and where a load (mN) is plotted against an ordinate and a displacement amount (m) is plotted against an abscissa, is 0.80 mN or more; and a method for producing thereof.

A magnetic carrier including a magnetic carrier particle having a magnetic carrier core and a resin coating layer formed on a surface of the magnetic carrier core, wherein the resin coating layer includes a resin component including a resin A and a resin B, the resin A is a copolymer of monomers including (a) a (meth)acrylic acid ester monomer having an alicyclic hydrocarbon group and (b) a specific macromonomer, the resin B is a copolymer of monomers including (c) a styrene-based monomer and (d) a specific (meth)acrylic acid ester monomer, and based on the resin components of the resin coating layer, the amount of the resin A is from 20% by mass to 99% by mass, and the amount of the resin B is from 1% by mass to 80% by mass.

A magnetic carrier including a magnetic carrier particle having a magnetic carrier core and a resin coating layer formed on a surface of the magnetic carrier core, wherein the resin coating layer includes a resin component including a resin A and a resin B, the resin A is a copolymer of monomers including (a) a (meth)acrylic acid ester monomer having an alicyclic hydrocarbon group and (b) a specific macromonomer, the resin B is a copolymer of monomers including (c) a styrene-based monomer and (d) a specific (meth)acrylic acid ester monomer, and based on the resin components of the resin coating layer, the amount of the resin A is from 20% by mass to 99% by mass, and the amount of the resin B is from 1% by mass to 80% by mass.

A toner having a toner particle including a binder resin and a wax, wherein the wax includes a specific diester compound; a proportion As of an area occupied by the wax in a region from a surface of the toner particle to 0.5 m is 15.0% or less; wax domains are observed in the cross section of the toner particle, and an average number of the domains per cross section of one toner particle is from 10 to 2000; when a mass concentration of a polyvalent metal element in the toner particle determined by fluorescent X-ray analysis is denoted by Mi (ppm), Mi is from 3.5 ppm to 1100 ppm; and when a mass concentration of a polyvalent metal element in the toner particle determined by X-ray photoelectron spectroscopy is denoted by Ms (ppm),
Mi>Ms.

A toner includes toner particles each including a toner mother particle. The toner mother particles contain a binder resin, a magnetic powder, and conductive titanium oxide particles. The conductive titanium oxide particles have an aspect ratio of at least 5.0. The amount of the conductive titanium oxide particles is at least 2 parts by mass and no greater than 10 parts by mass relative to 100 parts by mass of the binder resin.

Provided is an external additive having a resin particle containing a crystalline resin, and an inorganic fine particle containing a metal atom, the inorganic fine particle being embedded in the resin particle, wherein part of the inorganic fine particle being exposed on a surface of the resin particle, the maximum endothermic peak temperature of the external additive during a first temperature rise is from 50.0 C. to 120 C., the shape factor SF-2 of the external additive is from 110 to 150, and the external additive satisfies following formulae (1) and (2) below, in which Za (mass %) is the percentage content of a metal atom contained in the inorganic fine particle on the surface of the external additive in X-ray photoelectron spectroscopy, and Zb (mass %) is the percentage content of the metal atom in thermogravimetric analysis of the external additive,
Za15(1), and
Za/Zb0.7(2)

Provided is an external additive having a resin particle containing a crystalline resin, and an inorganic fine particle containing a metal atom, the inorganic fine particle being embedded in the resin particle, wherein part of the inorganic fine particle being exposed on a surface of the resin particle, the maximum endothermic peak temperature of the external additive during a first temperature rise is from 50.0 C. to 120 C., the shape factor SF-2 of the external additive is from 110 to 150, and the external additive satisfies following formulae (1) and (2) below, in which Za (mass %) is the percentage content of a metal atom contained in the inorganic fine particle on the surface of the external additive in X-ray photoelectron spectroscopy, and Zb (mass %) is the percentage content of the metal atom in thermogravimetric analysis of the external additive,
Za15(1), and
Za/Zb0.7(2)