A toner comprising: a toner particle comprising a binder resin and boric acid; wherein the binder resin comprises an amorphous resin and a crystalline polyester resin, a content of the crystalline polyester resin in the toner is 30.00 to 80.00 mass %, and a content of the boric acid in the toner is 0.10 to 10.00 mass %.

The present invention relates to a binder resin for toners which contains a composite resin that is formed by bonding a styrene-acrylic resin unit and a polyester-based resin unit to each other through a covalent bond, in which an acid value of a styrene-acrylic resin (A) constituting the styrene-acrylic resin unit is not less than 40 mgKOH/g.

Provided is an electrophotographic developer set having a toner and a powder adhesive, wherein the toner comprises a thermoplastic resin A; the powder adhesive comprises a thermoplastic resin B and a wax A; the wax A has two or more ester groups in the molecule; the thermoplastic resin B has an ester group; and in a viscoelasticity measurement, with Gt′(100) (Pa) being a storage elastic modulus at 100° C. of the toner, and Gb′(100) (Pa) being a storage elastic modulus at 100° C. of the powder adhesive, Gb′(100) is 1.00×10.sup.5 Pa or less, and Gt′(100)/Gb′(100) is 1.20 or more, as well as a method for producing a bonded product using the above electrophotographic developer set.

The present invention relates to a process for producing a toner for development of electrostatic images, including step (1): subjecting a polyhydric alcohol component and a polycarboxylic acid component to polycondensation reaction in the presence of a hydroxy group- or carboxy group-containing hydrocarbon wax (W1) to obtain a non-crystalline resin (A) containing a constitutional component derived from the hydrocarbon wax (W1) and also containing a polyester moiety; step (2): dispersing the non-crystalline resin (A) obtained in the step (1) in an aqueous medium to obtain an aqueous dispersion of resin particles (X); step (3): aggregating the resin particles (X) obtained in the step (2) in an aqueous medium in the presence of a crystalline polyester (B) to obtain aggregated particles; and step (4): coalescing the aggregated particles obtained in the step (3).

A toner having a toner particle containing a binder resin, an amorphous polyester, and a colorant, wherein a softening point of the toner is at least 110° C. and not more than 140° C.; an integrated value f1 for stress of the toner is not more than 10 g.Math.m/sec, as measured using a tack tester, with a temperature for a probe end being 150° C. and a press holding time being 0.01 seconds; and an integrated value f2 for stress of the toner is at least 30 g.Math.m/sec, as measured using a tack tester, with a temperature for a probe end being 150° C. and a press holding time being 0.1 seconds.

A method of producing a resin particle dispersion for toner, including, cooling a mixture including a resin particle dispersion containing an amorphous resin and a crystalline resin, and an aqueous medium. Where the cooling includes together fluidizing, continuously mixing, and continuously discharging the mixture of the resin particle dispersion and the aqueous medium.

A toner particle includes a binder resin, a colorant, a releasing agent, and a dispersant. The binder resin includes a non-crystalline polyester resin containing 1 to 15 mol % of a polyfunctional carboxylic acid unit having a pendant group with 3 to 32 carbons and a crystalline polyester resin. An endothermic amount Tg2nd-dH derived from the crystalline polyester resin is 4 to 40 J/g. The releasing agent has a melting point of 60 to 100° C. The dispersant has a melting point of 60 to 100° C. A mass ratio of the dispersant to the releasing agent is 50:50 to 95:5.

Provided is an electrostatic charge image developing toner including toner base particles containing a binder resin an a mold release agent, wherein a molecular weight corresponding to a main peak top of a molecular weight distribution curve of constituent components of the electrostatic charge image developing toner obtained by gel permeation chromatography is 15,000 or more; and in comparison of an area ratio of each peak in the molecular weight distribution curve, the binder resin contains an amorphous material of a low molecular weight component having a weight average molecular weight of 300 or more and less than 1000 in the area ratio of 10 to 20% with respect to the total amount of the binder resin.

A toner comprising a toner particle comprising a binder resin, a nonmagnetic inorganic oxide particle A, and a magnetic iron oxide particle B, wherein a softening point of a chloroform-soluble component of the toner particle is not greater than 90° C.; the nonmagnetic inorganic oxide particle A and the magnetic iron oxide particle B are internally added to the toner particle; the nonmagnetic inorganic oxide particle A comprises as its main component at least one element selected from the group consisting of Si, Mg, Al, Ti, and Sr; a proportion of the inorganic oxide particles having a long diameter of specific length is in specific range; and a value of a ratio of a number-average particle diameter of the long diameter for the nonmagnetic inorganic oxide particle A, to a number-average particle diameter of the long diameter for the magnetic iron oxide particle B, is 5 to 30.

A toner includes toner base particles and external additives deposited on a surface of the toner base particle. The toner base particle includes an amorphous polyester resin, a crystalline polyester resin, a release agent, and resin particles. An abundance ratio of the crystalline polyester resin in the surface of the toner base particle as observed by TEM is 2.5% or greater but 25% or less. The resin particles are deposited at the surface of the toner base particle as observed by SEM. A ratio of aggregates of the resin particles occupying the surface of the toner base particle is 1% or greater but 70% or less, where R is a major axis of the minimum particle of the resin particles, and the resin particle having a major axis of 3R or greater is determined as the aggregate.