Kao Corporation

Shogo Watanabe

Takashi Kubo

Takeshi Ashizawa

Norihiro Hirai

Akihiro Eida

Yuki Wakabayashi

Yasuhiro Hidaka

Kunihiro Kano

Hiroki Kakiuchi

Kohei Katayama

Kotaro Shimada

Arisa Yamamoto

Yuka Amaha

The invention relates to a toner for development of electrostatic images excellent in fusing property on polypropylene films and excellent in rubfastness of printed images, and a resin composition for a toner for development of electrostatic images. The toner for development of electrostatic images and the resin composition for a toner for development of electrostatic images each contain an amorphous polyester-based resin A and a crystalline polyester-based resin C, wherein the amorphous polyester-based resin A has a constituent moiety derived from a polyester resin, and a constituent moiety derived from a reactive functional group-having modified polyolefin-based polymer A, the polyester resin-derived constituent moiety and the modified polyolefin-based polymer A-derived constituent moiety being bonded via a covalent bond, and the amount of the modified polyolefin-based polymer A-derived constituent moiety is 5% by mass or more and 30% by mass or less relative to the total amount of the resin component in the toner.

Toner for development of electrostatic images

A positively charged toner for development of an electrostatic image, containing matrix particles containing at least a binder resin and a release agent, coated with inorganic fine particles, the binder resin containing a crystalline resin, the release agent containing ester wax (W) containing a dipentaerythritol unit as a constitutional component, the inorganic fine particles containing positively charged silica (S1) and negatively charged silica (S2), and the positively charged silica (S1) having an average particle diameter that is smaller than an average particle diameter of the negatively charged silica (S2), and the negatively charged silica (S2) having an average particle diameter of 10 nm or more and 90 nm or less.

Positively charged toner for electrostatic-image development

The present invention relates to a process for producing a toner for electrophotography that is excellent in the low-temperature fusing property, the initial image quality after storage, and the document offset property. A process for producing a toner for electrophotography, including step 1: melt-mixing a mixture containing a crystalline resin (C) and ester wax (W) having a dipentaerythritol unit as a constitutional component, wherein a difference |C&#x2212;W| between a melting point Cof the crystalline resin (C) and a melting point Wof the ester wax (W) is 30&#xb0; C. or less, and the melt-mixing is performed at a temperature Kthat is the melting point Cor more and the melting point Wor more.

Method for producing toner for electrophotography

A toner for electrophotography obtained by a method including: step 1: mixing a polyester and a polylactic acid at a temperature of 140&#xb0; C. or higher and 200&#xb0; C. or lower and subjecting the mixture to a transesterification reaction to provide a resin composition; and step 2: mixing the resin composition obtained in step 1 with a polyester which is identical to and/or different from the polyester of step 1, and a method for producing the toner. The toner for electrophotography of the present invention is suitably used in developing latent images formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or the like.

Toner for electrophotography

A toner for electrophotography containing a resin binder containing a crystalline resin and an amorphous resin, and a releasing agent, wherein the crystalline resin contains a crystalline composite resin C containing a polycondensation resin component and a styrenic resin component, wherein the polycondensation resin component is obtained by polycondensing a specified alcohol component and a specified carboxylic acid component, and wherein the amorphous resin contains an amorphous composite resin AC containing a polycondensation resin component and a styrenic resin component, wherein the polycondensation resin component is obtained by polycondensing an alcohol component and a specified carboxylic acid component, and an amorphous polyester AP obtained by polycondensing an alcohol component and a specified carboxylic acid component, wherein a softening point of the amorphous polyester AP is higher than a softening point of the amorphous composite resin AC, wherein a difference in softening points between the amorphous polyester AP and the amorphous composite resin AC is 10&#xb0; C. or more and 50&#xb0; C. or less. The toner for electrophotography of the present invention is suitably used in development of latent images or the like which is formed in, for example, electrostatic development method, electrostatic recording method, electrostatic printing method or the like.

Electrophotography toner

A method for producing a toner for electrostatic image development containing at least an amorphous polyester and a crystalline polylactic acid, including step 1: mixing an amorphous polyester and a crystalline polylactic acid at a temperature of from 140&#xb0; to 250&#xb0; C.; step 2: melt-kneading a mixture obtained in the step 1; and step 3: pulverizing and classifying a melt-kneaded product obtained in the step 2; and a toner for electrostatic image development obtainable by the method. The toner for electrostatic image development obtainable by the method of the present invention is suitably used in development or the like of latent images formed in an electrostatic development method, an electrostatic recording method, an electrostatic printing method, or the like.

Method for producing toner for developing electrostatic images

A method for producing a toner for electrostatic image development including the step of melt-kneading a mixture containing a resin binder and a wax, wherein the resin binder contains an amorphous polyester (A) obtained by polycondensing an alcohol component containing an aliphatic diol (a) having 3 or 4 carbon atoms, the aliphatic diol having a hydroxyl group bonded to a secondary carbon atom, and an aliphatic diol (b) containing one or more &#x3b1;,&#x3c9;-linear alkanediols having 2, 4, 6 or 8 carbon atoms, and a carboxylic acid component. The toner for electrostatic image development can be suitably used in, for example, the development or the like of latent image formed in an electrostatic development method, an electrostatic recording method, an electrostatic printing method, or the like.

Method for producing toner for electrostatic image development

A toner for electrostatic image development containing a resin binder and a releasing agent, wherein the resin binder contains a polyester A having a furan ring, and wherein the releasing agent contains an ester wax, and a method for producing the toner. The toner for electrostatic image development of the present invention can be suitably used in, for example, the development or the like of latent image formed in electrophotography, an electrostatic recording method, an electrostatic printing method, or the like.

Toner for electrostatic image development

A method for producing a toner for electrostatic image development containing at least a resin binder and a charge control agent, including step 1: melt-kneading components containing a resin binder and a charge control agent to provide a melt-kneaded product; and step 2: pulverizing the melt-kneaded product, and classifying a pulverized product, wherein the resin binder contains a polyester A obtained by polycondensing an alcohol component containing 1,2-propanediol and a carboxylic acid component containing a rosin compound and an aliphatic dicarboxylic acid compound having 6 to 10 carbon atoms, wherein 1,2-propanediol is contained in the alcohol component of the polyester A in an amount of 85% by mol or more. The toner for electrostatic image development obtained by the method of the present invention can be suitably used in, for example, the development or the like of latent image formed in electrophotography, an electrostatic recording method, an electrostatic printing method, or the like.

A toner containing a resin binder and a colorant, wherein the resin binder contains a crystalline resin and an amorphous resin, the crystalline resin containing a composite resin containing: a polycondensation resin component obtained by polycondensing an alcohol component containing an aliphatic diol having 2 to 10 carbon atoms, and a carboxylic acid component containing an aromatic dicarboxylic acid compound, and a styrenic resin component, and the amorphous resin containing a polyester obtained from an alcohol component containing an aliphatic diol in an amount of 60% by mol or more, and a carboxylic acid component. The toner of the present invention is suitably used in, for example, the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.

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Izumiotsu, Japan

Shogo Watanabe