Kao Corporation

Shoichi Murata

Eiji Shirai

Hiroshi Mizuhata

Manabu Suzuki

Yuki Wakabayashi

Tomohide Yoshida

Takahiro Yoshikawa

Hiroto Hayashi

Motomu Shibata

Nobumichi Kamiyoshi

Takashi Kubo

Norihiro Fukuri

Koji Shimokusa

Koji Kameyama

Takayuki Ikenaga

Osamu Yamashita

Takashi Okuno

Hiroki Kubo

Keishi Yokota

Kojiro Kameyama

Provided are a binder resin composition for toner excellent in low-temperature fusing property, storage stability and durability, a toner for developing electrostatic images that contains the binder resin composition for toner, and a method for producing the binder resin composition for toner. The binder resin composition for toner contains a resin composition (C-P) prepared by condensing an acid group-having crystalline resin (C) and a polyalkyleneimine, and an amorphous resin (A).

Binder resin composition for toner

A method for producing a toner, including aggregating and coalescing resin particles and colorant particles in an aqueous medium. The resin particles contain, in the same or different particles, an amorphous polyester-based resin which is a polycondensate of an alcohol component containing an aromatic alcohol and a carboxylic acid component, and a crystalline polyester resin. The colorant particles contain a colorant and an addition polymer of a raw material monomer containing an addition-polymerizing monomer having an aromatic group. A ratio by mass of the colorant to the addition polymer in the colorant particles is 50/50 or more and 95/5 or less.

Toner production method

A method for producing a toner, including aggregating and coalescing resin particles and colorant particles. The resin particles contain a composite resin containing a polyester resin segment, an addition polymer resin segment which is an addition polymerized product of a raw material monomer containing a styrenic compound, and a structural unit derived from a bireactive monomer bonding to the polyester resin segment and the addition polymer resin segment via a covalent bond. The colorant particles contain a colorant and an addition polymer of a raw material monomer containing a styrenic compound. The addition polymer contains a structural unit derived from the styrenic compound in the main chain. A ratio by mass of the colorant to the addition polymer in the colorant particles is 50/50 or more and 95/5 or less.

The present invention provides a toner for development of electrostatic images including a polyester-based resin and a polypropylene-based wax, which is excellent in fusing properties on a polypropylene film. The present invention relates to [1] a resin binder composition for toners for development of electrostatic images which has an endothermic amount ratio &#x394;Hof not less than 0.10 and not more than 0.80, [2] a resin binder composition for toners for development of electrostatic images in which a volume-median particle size (D) of a wax as a whole contained therein is not less than 1 &#x3bc;m and not more than 50 &#x3bc;m; a volume-median particle size (D) of a small particle size component of the wax is not less than 20 nm and not more than 400 nm; and a content of the small particle size component in the wax is not less than 20% by mass and not more than 90% by mass, [3] a process for producing a resin binder composition for toners for development of electrostatic images in which a polypropylene-based wax is added to a reaction system prior to addition polymerization upon production of a composite resin as a resin binder; and [4] a toner for development of electrostatic images including the resin binder composition as described in the above [1] or [2].

Binder resin composition for electrostatic image developing toners

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).

Method for producing toner for developing electrostatic image

The present invention relates to a process for producing a toner for development of electrostatic images, including the following steps (1) to (3): Step (1): aggregating resin particles (X) containing a composite resin that contains a segment constituted of a polyester resin (a) obtained by polycondensing an alcohol component containing 80 mol % or more of a propyleneoxide adduct of bisphenol A and a polycarboxylic acid component, and a vinyl-based resin segment containing a constitutional unit derived from a styrene-based compound, in an aqueous medium, to obtain aggregated particles (1); Step (2): aggregating the aggregated particles (1) obtained in the step (1) with resin particles (Y) containing a polyester resin (b) obtained by polycondensing an alcohol component containing 80 mol % or more of an ethyleneoxide adduct of bisphenol A and a polycarboxylic acid component to obtain aggregated particles (2); and Step (3): coalescing the aggregated particles (2) obtained in the step (2).

Process for producing toner for development of electrostatic images

The present invention relates to a process for producing a resin particle dispersion, including a step (1) of mixing a polyester resin and a basic aqueous solution to obtain a resin neutralized product; and a step (2) of adding an aqueous medium to the resin neutralized product obtained in the step (1) to emulsify the resin neutralized product, in which a concentration of an ester group in the polyester resin is from 6.3 to 12 mmol/g, a pH of the basic aqueous solution as measured at 25&#xb0; C. is from 8.5 to 13.5, and a content of an organic solvent in the resin neutralized product is not more than 10% by mass; and a process for producing a toner for development of electrostatic images, including steps of aggregating and coalescing the resin particles in the obtained resin particle dispersion. The present invention provides a process for producing a dispersion of resin particles having a small particle size and a narrow particle size distribution, and a process for producing a toner that has a narrow particle size distribution and is excellent in dot reproducibility and charge stability.

Method for producing resin particle dispersion, and method for producing toner for electrostatic charge image development use

The present invention relates to a toner for electrophotography including core-shell particles as a resin binder each including a core portion containing an amorphous resin (A) having a softening point of 105&#xb0; C. or lower which is obtained by polycondensing a carboxylic acid component containing an alkenyl succinic acid with an alcohol component; and a shell portion containing an amorphous resin (B) obtained by polycondensing an alcohol component containing an aliphatic diol having 2 to 6 carbon atoms with a carboxylic acid component containing a trivalent or higher-valent polycarboxylic acid compound in an amount of 20 mol % or less. The toner for electrophotography according to the present invention is excellent in heat resistant storage property, low-temperature fusing property and durability.

Toners for electrophotography

The present invention relates to a process for producing a toner for electrophotography which includes the step of fusing aggregated particles containing resin particles (A) and releasing agent particles in an aqueous mixed solution containing the aggregated particles and an anionic surfactant having a polyalkylene glycol moiety with an average molar number of addition of an alkylene oxide having 2 to 3 carbon atoms of from 5 to 100 after and/or while adjusting a pH value of the aqueous mixed solution to 2.0 to 6.0 as measured at 25&#xb0; C., and a toner for electrophotography obtained by the process.

Process for producing toner for electrophotography

The present invention relates to a process for producing a dispersion of polyester particles which includes the step of emulsifying mixed polyester containing (1) an amorphous polyester containing a constitutional unit derived from a trivalent or higher-valent carboxylic acid in an amount of from 2.0 to 12.0 mol % on the basis of whole constitutional units of the whole amorphous polyester and (2) a crystalline polyester, in an aqueous medium in a single vessel, or the step of mixing the mixed polyester with an organic solvent and then adding the aqueous medium to the resulting mixture to emulsify the mixed polyester in a single vessel. The present invention also relates to a dispersion of polyester particles produced by the above production process, as well as a toner for electrophotography which is produced by subjecting the dispersion of the polyester particles to aggregation and coalescence and is excellent in both of a low-temperature fusing property and an anti-hot offset property, and a process for producing the toner.

Manufacturing method for polyester particle dispersion liquid

A method for producing an electrophotographic toner, including steps of: (1) preparing a thermally treated resin particle dispersion by retaining, for one hour or longer at a temperature satisfying the formula: (melting point of the crystalline polyester (a1)&#x2212;35) (&#xb0; C.)&#x3c;T&#x3c;melting point of the crystalline polyester (a1) (&#xb0; C.), a dispersion of resin particles (A) having a volume median particle size of 0.02-2 &#x3bc;m and containing a resin containing a crystalline polyester (a1) of 1-50 wt % and an amorphous polyester (b1); (2) preparing an aggregated particle dispersion by aggregating thermally treated resin particles contained in the thermally treated resin particle dispersion prepared through step 1; (2a) preparing resin-fine-particle-attached aggregated particles by adding, to the aggregated particle dispersion prepared through step 2, a dispersion of resin fine particles (B) containing an amorphous polyester (b2) of 70 wt % or more; and (3) unifying the resin-fine-particle-attached aggregated particles prepared through step 2a.

Process for production of electrophotographic toner

The present invention relates to a toner for electrophotography including a polyester obtained by subjecting a crystalline polyester-containing aqueous dispersion and a non-crystalline polyester-containing aqueous dispersion to aggregation and coalescence, as a resin binder, wherein the crystalline polyester is produced by polycondensing an alcohol component containing 70 mol % or more of an aliphatic diol having 2 to 8 carbon atoms with a carboxylic acid component containing 50 mol % or more of terephthalic acid. The toner is excellent in low-temperature fusing ability and pressure storage stability.

The present invention relates to a resin binder for toners which includes core/shell particles each including a core portion containing a crystalline polyester obtained by polycondensing an alcohol component containing an aliphatic diol having 2-12 carbon atoms and a carboxylic acid component containing an aliphatic dicarboxylic acid compound having 8-12 carbon atoms in an amount of 70-100 mol %, and a non-crystalline resin (A) obtained by polycondensing an alcohol component and a carboxylic acid component containing at least one succinic acid compound selected from the group consisting of an alkyl (C-C) succinic acid and an alkenyl (C-C) succinic acid in an amount of 3-60 mol %; and a shell portion containing a non-crystalline resin (B) obtained by polycondensing a carboxylic acid component and an alcohol component containing an aliphatic dialcohol having 2-5 carbon atoms in an amount of 80 mol % or more.

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Wakayama, Japan

Shoichi Murata