A toner includes toner particle containing at least a strontium titanate particle on the surface of the toner particle, and the toner is a water-washed toner from which strontium titanate particle desorbable by water washing are removed by water washing. The water-washed toner contains the strontium titanate particle having a number average particle diameter of primary particle (D1) of 10 nm or more and 150 nm or less, and when the distribution of an Sr element in the water-washed toner in the depth direction is determined, (i) the Sr element abundance on the outermost surface x satisfying 0.00<x0.80, and (ii) the difference between x and xp xpx satisfying 0.00<xpx0.95, where xp is the maximum peak value (atomic %) of the Sr element abundance in the region from the outermost surface to 50 nm.

An image forming apparatus in which occurrence of an image failure in association with contamination caused by an external additive, such as silica, adhering to a charging unit is suppressed. The image forming apparatus is configured to charge an image bearing member through use of the charging unit, and uses toner having, on a surface thereof, strontium titanate particles and silica particles having predetermined physical properties.

A toner having a toner particle, which contains a binder resin, and inorganic fine particles, the toner being characterized in that the binder resin contains a polyester resin, the polyester resin has, at a terminal, an alkyl group having an average number of carbon atoms of from 4 to 102, the number average particle diameter of primary particles of the inorganic fine particles is from 10 to 90 nm, the dielectric constant of the inorganic fine particles is from 55.0 to 100.0 pF/m, as measured at 25 C. and 1 MHz, and the inorganic fine particles are surface-treated with an alkylalkoxysilane represented by formula (1) below:

C.sub.nH.sub.2n+1SiOC.sub.mH.sub.2m+1).sub.3(1)

in formula (1), n denotes an integer of from 4 to 20, and m denotes an integer of from 1 to 3.

A toner includes toner particles, wherein the toner particles contain a polymer containing a structural unit derived from an azobenzene derivative having a polymerizable group.

Provided is an image forming method for forming an image including a recording medium and a layer containing a photosoftening compound disposed thereon, the image forming method containing the steps of: supplying a powder for adhering the powder to the image; and irradiating the image with light to melt or to soften the image.

An electrostatic charge image developer includes: a toner that includes toner particles which contain a polyester resin and a styrene (meth)acrylic resin and form a sea-island structure which includes a sea portion containing the polyester resin and an island portion containing the styrene (meth)acrylic resin on a surface of the toner particle, and has an exposure rate of the styrene (meth)acrylic resin in a range of from about 5 atom % to about 20 atom %; and an external additive, and a carrier whose fluidity and bulk density under environment of a temperature of 25 C. and a humidity of 50% satisfy Expression: 65.0fluiditybulk density72.5.

A toner comprises a toner particle and an external additive, the toner satisfies a certain relationship with regard to l (C/m.sup.2) and s (C/m.sup.2). The toner is divided into two groups i.e. a first group and a second group with inertial classifier, the first group including a larger size of the toner particles, and the second group including a smaller size of the toner particles, and the number of the toner particles in the first group being substantially equal to the number of the toner particles in the second group. Then, al (C/m.sup.2) represents an absolute value of average surface charge density of the toner included in the first group, and s (C/m.sup.2) represents an absolute value of average surface charge density of the toner included in the second group.

The electrostatic charge image developing toner of the present invention is an electrostatic charge image developing toner including a toner mother particle including at least a binding resin, and an external additive attached onto a surface of the toner mother particle, wherein a median size on a volume basis of the toner mother particle is in the range from 3.0 to 5.0 m, the binding resin contains at least an amorphous polyester resin as a main component, and a spherical silica particle (1) having a number average particle size in the range from 20 to 55 nm is included as the external additive.

Provided is a toner having a toner particle, wherein the toner particle contains a polyester resin and a fatty acid metal salt, the toner contains a tetrahydrofuran-soluble component A with a molecular weight of at least 1,000 and not more than 5,000, as measured by gel permeation chromatography, in an amount of at least 25 mass % and not more than 80 mass %, and a mass ratio of the fatty acid metal salt to the tetrahydrofuran-soluble component A is at least 0.003 and not more than 0.060.

Provided is an image recording composition used for an electrostatic image developing toner or an ink-jet ink, containing a photoisomerization compound which is a stilbene derivative having a structure represented by Formula (1),

##STR00001##

wherein R.sub.1 represents an electron donating group; R.sub.2 represents an electron withdrawing group; R.sub.3 to R.sub.10 each independently represent a hydrogen atom or an alkyl group which may have a branch, provided that at least one of R.sub.3 to R.sub.10 represents an alkyl group which may have a branch.