Toners are provided which may comprise toner particles, a colorant, and optionally, a wax, wherein the toner particles comprise a resin comprising a polymerization product of reactants comprising a dioxane/dioxolane monomer and a vinyl co-monomer, wherein the dioxane/dioxolane monomer is an ester of (meth)acrylic acid with an alcohol comprising a dioxane moiety, an ester of (meth)acrylic acid with an alcohol comprising a dioxolane moiety, or both.

The present invention provides an aqueous pigment dispersion liquid being such that a pigment is finely dispersed, and the viscosity, and the particle diameters of the pigment are unlikely to fluctuate, being excellent in storage stability, and enabling preparation of an emulsion-polymerized toner having properly controlled particle diameters while improving the pigment utilization rate. The aqueous pigment dispersion liquid is an aqueous pigment dispersion liquid for an emulsion-polymerized toner containing a pigment, a dispersant, and an aqueous medium. The dispersant is a polymer containing a constitutional unit (A) derived from a monomer (A) such that a group containing a (meth)acryloyloxy group or the like is bonded to one end of a particular polyethylene glycol chain or the like, and a constitutional unit (B) derived from a monomer (B) having a carboxy group or the like, the polymer has a number average molecular weight in terms of polystyrene of 4,000 to 15,000, as measured by gel permeation chromatography, the polymer is contained in a state of being not ionized substantially, and the aqueous pigment dispersion liquid has a pH of 3.0 to 8.4.

Provided is a toner has a toner particle containing a binder resin and is characterized in that the binder resin contains a polymer A, which is a polymer of a composition containing a first polymerizable monomer, a second polymerizable monomer and a crosslinking agent, the first polymerizable monomer is at least one monomer selected from the group consisting of (meth)acrylic acid esters having an alkyl group with 18 to 36 carbon atoms, the crosslinking agent has two or more polymerizable double bonds, a content of the first polymerizable monomer in the composition is 5.0 to 60.0 mol %, a content of the second polymerizable monomer is 20.0 to 95.0 mol %, and when the SP values of the first polymerizable monomer, the second polymerizable monomer and the crosslinking agent are denoted by SP.sub.12, SP.sub.22 and SP.sub.C2, respectively, the formulae 0.60≤(SP.sub.22−SP.sub.12)≤15.00 and SP.sub.12<SP.sub.C2<(SP.sub.22+3.00) are satisfied.

A toner including toner particles having a resin component containing a crystalline resin and an amorphous resin, in which the resin component contains a tetrahydrofuran-insoluble component, and the content of the tetrahydrofuran-insoluble component with respect to the content of the resin component is 5.0% to 80.0% by mass, wherein a maximum endothermic peak temperature of the tetrahydrofuran-insoluble component is 55.0 to 80.0° C., and the amount of heat absorption in the maximum endothermic peak of the tetrahydrofuran-insoluble component is 10.0 to 80.0 Pa, and toner particles have a structure which comprises a matrix containing the crystalline resin and domains containing the amorphous resin.

A resin composition includes: a resin having a first group capable of forming at least two hydrogen bonds; and a photoisomerization compound having a second group capable of forming at least two hydrogen bonds complementarily with the first group and having a moiety that is reversibly isomerized by light.

The present invention relates to a toner binder containing: a polyester resin (A); and a vinyl resin (B), wherein the polyester resin (A) has an acid value of 2 mg KOH/g or more, the vinyl resin (B) has a weight average molecular weight of 4,000 to 40,000, the vinyl resin (B) is a polymer essentially containing a monomer (m) whose homopolymer has an SP value of 11.5 to 16.5 as a constituent monomer, the weight percentage of the monomer (m) in monomers constituting the vinyl resin (B) is 1 wt % or more based on the total weight of the monomers constituting the vinyl resin (B), the polyester resin (A) and the vinyl resin (B) are present at a weight ratio (A)/(B) of 80/20 to 99.5/0.5, and when the vinyl resin (B) contains polyethylene units (C11) having a degree of polymerization of 70 to 210 and/or polypropylene units (C12) having a degree of polymerization of 70 to 210, the total weight percentage of the polyethylene units (C11) and the polypropylene units (C12) in the vinyl resin (B) is 9 wt % or less based on the weight of the vinyl resin (B).

A toner including toner particles comprising at least one resin, in combination with an optional colorant, and an optional wax; and a copolymer toner additive on at least a portion of an external surface of the toner particles, the copolymer toner additive comprising a first monomer having a high carbon to oxygen ratio of from about 3 to about 8; and a second monomer comprising two or more vinyl groups, wherein the second monomer is present in the copolymer in an amount of from greater than about 8 percent by weight to about 60 percent by weight, based on the weight of the copolymer; wherein the copolymer toner additive has a volume average particle diameter of from about 20 nanometers to less than about 70 nanometers. An emulsion aggregation toner process including the copolymer as a toner surface additive.

A toner comprising a toner particle containing a binder resin, the storage elastic modulus Gt′ (150) of the toner at 150° C. is at least 1.0×10.sup.4 Pa, the binder resin contains a polymer A having a first monomer unit derived from a first polymerizable monomer and a second monomer unit derived from a second polymerizable monomer different from the first polymerizable monomer, the first polymerizable monomer is selected from specific (meth)acrylic acid esters, the contents of the first monomer unit and second monomer unit in the polymer A are within specific ranges, and the SP values of the first monomer unit and second monomer unit are within specific ranges.

A toner comprising: a toner particle that comprises a core particle comprising a binder resin, and a shell layer comprising a thermoplastic resin on a surface of the core particle; and organosilicon polymer particles on a surface of the toner particle, wherein a peak top molecular weight of the thermoplastic resin, according to measurement by gel permeation chromatography, is 30000 to 500000, a number-average primary particle diameter of the organosilicon polymer particles is 10 nm to 500 nm, and an absolute value of a difference (ΔSP) between an SP value (SP.sub.Si) of the organosilicon polymer particles and an SP value (SP.sub.Sh) of the thermoplastic resin present in the shell layer is not more than 2.30.

A toner is provided, which has a toner particle containing a binder resin including a first resin and a second resin, wherein the first resin is a crystalline resin, the second resin is an amorphous resin, the first resin contains a specific amount of a first monomer unit having a specific structure, an acid value of the first resin and an acid value of the second resin are within specific ranges, a domain-matrix structure formed of a matrix containing the first resin and domains containing the second resin appears in cross-sectional observation of the toner, the toner particle contains a multivalent metal element, the multivalent metal element is at least one metal element selected from the group consisting of Mg, Ca, Al, Fe and Zn, and a total content of the multivalent metal element is within a specific range.