Sanyo Chemical Industries, Ltd.

Sanyo Chemical Ind., Ltd.

Tomohisa Kato

Yuko Sugimoto

Hiroshi Odajima

Satoshi Utsui

Eiji Iwawaki

Mana Sanpei

Yasuhiro Ono

Masaru Honda

Hideo Nakanishi

Masakazu Iwata

Naoki Takase

Hiroshi Kishiki

Yoko Sakurai

Takashi Niinae

Syuji Yamada

Shigeo Ochiai

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).

Toner binder and toner

The toner binder of the present invention contains a crystalline resin (A) and a resin (B) that is a polyester resin or its modified resin, the polyester resin being obtained by reaction of an alcohol component (X) and a carboxylic acid component (Y) as raw materials, wherein a temperature (Tp) of the top of an endothermic peak derived from the crystalline resin (A) as measured by a differential scanning calorimeter (DSC) is in the range of 40&#xb0; C. to 100&#xb0; C., and endothermic peak areas Sand Sduring heating satisfy the following equation.()&#xd7;100&#x2265;35&#x2003;&#x2003;(1)Sis an area of the endothermic peak derived from the crystalline resin (A) in the first heating process, and Sis an area of the endothermic peak derived from the crystalline resin (A) in the second heating process, when the toner binder is heated, cooled, and heated.

Toner binder, and toner

The toner binder of the present invention contains a crystalline resin (A) and a resin (B) that is a polyester resin or its modified resin, the polyester resin being obtained by reaction of an alcohol component (X) and a carboxylic acid component (Y) as raw materials, wherein a temperature (Tp) of the top of an endothermic peak derived from the crystalline resin (A) as measured by a differential scanning calorimeter (DSC) is in the range of 40&#xb0; C. to 100&#xb0; C., and endothermic peak areas Sand Sduring heating satisfy the following equation.()&#xd7;100&#x2267;35&#x2003;&#x2003;(1)Sis an area of the endothermic peak derived from the crystalline resin (A) in the first heating process, and Sis an area of the endothermic peak derived from the crystalline resin (A) in the second heating process, when the toner binder is heated, cooled, and heated.

A toner binder for electrophotography excellent in low temperature fixing properties and anti-hot offset properties comprising styrene (co)polymer(s) (A) comprising a modified styrene (co)polymer modified by unsaturated dicarboxylic acids of C4 to C30, ester-forming derivatives thereof, (meth)acrylic acid, or alkyl (meth)acrylates (alkyl group of C1 to C24); said modified styrene (co)polymer containing constituent units derived from a monomer used in the modification is 0.1 to 9 wt %, and a toner using the toner binder. The (co)polymer(s) (A) includes a species that shows at least one GPC peak each in the regions of the molecular weight of 2,000 to 20,000 and 50,000 to 5 million.

Toner binder for electrophotography and toner

The present invention provides a toner binder for developing electrostatic charge images, Furthermore, the present invention provides a toner binder for developing electrostatic charge images,

Resin for toner binder and toner composition

A toner binder for dry toners which comprises a polyester; and a process for producing the toner binder. A known conventional technique for imparting low-temperature fixing property and anti-hot offset property to a toner binder is to use a mixture of two powdery polyesters. However, when the two polyesters mixed differ greatly in softening point, the effect of mixing is not obtained and pigments show poor dispersibility during toner production. The toner binder and the process eliminate these problems. The toner binder comprises aggregates of binder resin particles comprising two polyesters (A) and (B), wherein the polyester (A) has a higher softening point than the polyester (B) and the polyesters (A) and (B) have been evenly mixed in each particle. The process for producing a toner binder is characterized by melt-mixing the two polyesters (A) and (B) at 80 to 180&#xb0; C. The toner binder is used mainly as an ingredient for dry toners.

Toner binder and process for producing the same

A toner binder for electrophotography is provided whose minimum fixing temperature is low, image offsetting temperature to the heat-roll is high, and whose stability upon storage is good. The toner binder comprises a thermoplastic resin (I) of 10 to 50% by weight, i.e., a copolymer having a structural unit consisting of a styrene series monomer and a (meth)acrylic monomer, having a molecular weight of more than 30,000 when fractionated by gel permeation chromatography, having a glass transition temperature of -20.degree. to +40.degree. C.; and a thermoplastic resin (II) of 10 to 50% by weight, i.e., a polymer selected from a copolymer (II-a) of a vinyl monomer selected from group consisting of styrene and substituted styrenes, a copolymer (II-b) having a structural unit consisting of styrene series monomers and (meth)acrylic monomers, polyester resin (II-c), and a copolymer (II-d) including a moiety of a copolymer (II-b) and a moiety of a polyester resin (II-c). The toner binder has a molecular weight up to 30,000 when fractionated by gel permeation chromatography, and a glass transition temperature of 50.degree. to 100.degree. C. These thermoplastic resins are blended to exhibit a difference of 25.degree. to 100.degree. C. between the respective glass transition temperatures thereof.

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Kyoto, Japan

Tomohisa Kato