A two-component developer 100 includes a carrier 200 and a toner 300. The carrier 200 satisfies the relationships 100≤α≤220 and 300≤β≤480 when a voltage is applied in 1 V steps by a bridge resistance measurement method, where α (V) is a carrier voltage value obtained when a current value flowing through the carrier 200 reaches 1.0.sup.−7 (A), and β (V) is a carrier voltage value obtained when the current value reaches 1.0.sup.−5 (A).

A liquid electrophotographic ink composition is disclosed herein. One example of the liquid electrophotographic ink composition includes a resin, a liquid carrier, a pigment chosen from titanium oxide, and a spacer chosen from barium sulfate, calcium carbonate, clay, magnesium silicate and mixtures thereof, in an amount from 5 to 15 wt. % of the total solids of the composition. A method for making a liquid electrophotographic ink composition is also disclosed herein.

A toner comprising a toner particle containing a resin component, wherein the resin component contains an amorphous polyester and a crystalline polyester, and in depth profile measurement of secondary ions on the toner particle surface by TOF-SIMS, given Ia(t) as the intensity of secondary ions derived from the amorphous polyester, Ic(t) as the intensity of secondary ions derived from the crystalline polyester, and I(t) as the total detected intensity of secondary ions derived from resin contained in the toner particle at a depth of t (nm) from the toner particle surface, the following formulae are satisfied within the range of 0≤t≤10:
Ia(t)>Ic(t)>0.0000
(Ia(t)+Ic(t))/I(t)≥0.80
and there is only one point of intersection between the depth profile curve of Ia(t) and Ic(t) within the range of 10≤t≤30.

A toner comprising a toner particle and an external additive, wherein the external additive comprises a composite particle comprising an organosilicon polymer fine particle covering a surface of an alumina particle, a coverage ratio of the surface of the alumina particle with the organosilicon polymer fine particle is 1 to 50 area %, and given A (nm) as a number-average particle diameter of primary particles of the organosilicon polymer fine particle and B (nm) as a number-average particle diameter of primary particles of the alumina particle, following formulae (I) and (II) are satisfied:
A≤90  (I)
100≤B≤1000  (II).

The present disclosure relates to an electrophotographic ink composition. The composition comprises thermoplastic polymer, solder material, conductive filler and liquid carrier. The present disclosure also relates to a method of printing a conductive trace on a print substrate. The method comprises electrophotographically printing the electrophotographic ink composition described above onto a print substrate.

A toner including a toner particle that contains a binder resin, and an inorganic fine particle, wherein the inorganic fine particle contains aggregated particles; the aggregated particles contain primary particles of at least one metal salt selected from the group consisting of titanate metal salts and zirconate metal salts; the primary particles have a number-average particle diameter of from 15 nm to 55 nm; the aggregated particles have an aggregation diameter of from 80 nm to 300 nm, the aggregated particles have a volume resistivity of from 2×10.sup.9 Ω.Math.cm to 2×10.sup.13 Ω.Math.cm; and the aggregated particles cover a surface of the toner particle, and a coverage ratio of the aggregated particles with respect to the surface of the toner particle is from 0.3 area % to 10.0 area %.

A dispersant-attached polytetrafluoroethylene particle includes a polytetrafluoroethylene particle and a dispersant that attaches to a surface of the polytetrafluoroethylene particle and contains a fluorine atom. The particle size distribution index [D.sub.50-D.sub.10] is less than 50 nm and the electrical conductivity is 7 μS/cm or less.

A toner comprising: a toner particle that includes a binder resin, and an external additive, wherein the toner particle includes a polyester resin on the surface; the toner particle includes a polyvalent metal element; where an electrical resistivity of the polyvalent metal element at 20° C. is denoted by A Ω.Math.m, and an amount of the polyvalent metal element in the toner particle is denoted by B μmol/g, a following relationship is satisfied:
0.025×10.sup.8≤(1/A)×B≤4.500×10.sup.8; the external additive includes silica particles; and the silica particles includes spherical silica particles having a number average particle diameter of from 20 nm to 40 nm.

A toner having: a toner particle containing a binder resin including a first resin and a second resin; and an inorganic fine particle on a surface of the toner particle, wherein the first resin has a specific content ratio of a specific monomer unit, acid values of the first unit and second unit are within specific ranges, a domain matrix structure including a matrix containing the first resin and domains containing the second resin appears in cross-sectional observation of the toner, a compound having an alkyl group is present on a surface of the inorganic fine particle, and a volume resistivity of the inorganic fine particle is 1.0×10.sup.5 Ω.Math.cm to 1.0×10.sup.13 Ω.Math.cm.

An image forming apparatus comprising an electrophotographic photosensitive member and a developing device for supplying a toner onto the electrophotographic photosensitive member, the developing device having the toner, wherein the electrophotographic photosensitive member has a surface layer comprising a binder resin (A), the toner has a toner particle, the toner particle has a core comprising a binder resin (B) and a wax and a shell layer formed on a surface of the core, the binder resin (A) has a prescribed structure: the wax comprises a prescribed monoester compound: and a process cartridge.