Canon Kabushiki Kaisha

Other

Satoshi Handa

Manabu Ohno

Akira Hashimoto

Keiji Komoto

Yasukazu Ayaki

Yasuhiro Hashimoto

Koji Abe

Satoshi Yoshida

Tsutomu Kukimoto

Yushi Mikuriya

Shinya Yachi

Yuji Moriki

Emi Tosaka

Hiroaki Kawakami

Katsuyuki Nonaka

Kazumi Yoshizaki

Tsuyoshi Takiguchi

Koji Inaba

Tatsuya Nakamura

Naoya Isono

Masanori Ito

Takashige Kasuya

Akira Sugiyama

Yuhei Terui

Kiyokazu Suzuki

Yoshihiro Nakagawa

Michihisa Magome

Tatsuhiko Chiba

Hitoshi Itabashi

Hiroshi Yusa

Atsuyoshi Abe

Satoshi Matsunaga

Yasushi Katsuta

Ryota Kashiwabara

Yuki Karaki

Nobuhisa Abe

A toner which has i) toner base particles containing at least a binder resin and a colorant and ii) a fatty acid metal salt composition as an external additive. The fatty acid metal salt composition contains a nonionic surface-active agent and a fatty acid metal salt. This toner and an image forming process making use of the toner can keep the toner from adhering to a toner carrying member throughout running, promise a stable chargeability of the toner and can keep any deterioration of halftone image quality from being caused by excess charging of the toner and any image fog from being caused by insufficient charging of the toner.

Toner and image forming process

A toner is provided which is excellent in development stability in both a low-temperature, low-humidity environment and a high-temperature, high-humidity environment over a long time period. The toner includes toner particles containing at least a binder resin and a colorant, and a fatty acid metal salt. The fatty acid metal salt has a volume-based median diameter (D50s) of 0.15 &#x3bc;m or more and 0.65 &#x3bc;m or less, and the liberation ratio of the fatty acid metal salt in the toner is 1.0% or more and 25.0% or less.

Toner

A toner including toner particles containing at least a binder resin and a colorant. The binder resin is a vinyl-based resin. The toner contains a THF insoluble matter in a quantity of 0.0 mass % or more to less than 16.0 mass %. The toner has a main peak in a molecular weight domain Drranging from 5,000 to 80,000 in measurement of THF soluble matter of the toner with a gel permeation chromatogram (GPC)-differential refractive index detector (RI), and the toner has a main peak in a molecular weight domain Dmranging from 10,000 to 120,000 and at least one peak in a molecular weight domain Dmranging from 300,000 to 7,000,000 in the GPC-RI measurement in measurement with a GPC-multi-angle laser light scattering detector (MALLS).

A non magnetic toner comprises toner particles each containing at least a binder resin, a colorant and a wax component. The toner further comprises an inorganic fine powder. A storage elastic modulus at 110&#xb0; C. (G') of the non magnetic toner is in a range of 2.00&#xd7;10to 2.00&#xd7;10dN/m. A storage elastic modulus at 150&#xb0; C. (G&#x2032;) of the non magnetic toner is in a range of 3.00&#xd7;10to 2.00&#xd7;10dN/m. The toner particles are obtained by dispersing a polymerizable monomer composition containing polymerizable monomers, the colorant, the wax component and a low-molecular weight polymer into an aqueous medium, granulating the dispersed polymerizable monomer composition, and polymerizing the polymerizable monomers in granulated particles. The low-molecular weight polymer has a weight average molecular weight (Mw) measured by means of gel permeation chromatography (GPC) in a range of 2000 to 5000.

Non-magnetic toner

In a chart of molecular weight distribution measured of a toner, i) the toner has a main peak in the region of molecular weight of 16,000 to 60,000, and ii) where the molecular weight at the main peak is represented by M1, and where the height at the molecular weight M1 is represented by H(M1), the height at a molecular weight of 4,000 by H(4000) and the height at a molecular weight of 15,000 by H(15000), the H(4000), the H(15000) and the H(M1) satisfy a specific proportion. The toner has a weight-average molecular weight (Mw) of 15,000 to 80,000, and, in an endothermic chart, i) the toner has an endothermic main peak in the range of 40 to 130&#xb0; C., and ii) the calorimetric integral value represented by the peak area of the endothermic main peak is 10 to 35 J per 1 g of the toner.

Toner, and toner production process

In a toner having toner particles which comprise toner base particles containing at least a colorant, a release agent and a polar resin, and an inorganic fine powder, the polar resin is a resin having at least a polyester unit, synthesized in the presence of an aromatic carboxylic acid titanium compound used as a catalyst, and has an acid value of from 3 mgKOH/g to 35 mgKOH/g. The toner base particles are obtained by carrying out granulation in an aqueous medium, and the toner has a weight-average particle diameter of from 4.0 &#x3bc;m to 10.0 &#x3bc;m.

A toner is provided which is excellent in low-temperature fixability and offset resistance, has a wide fixing temperature range, provides fixed images with high gloss, and can form toner images having high quality. The toner is composed of toner particles having toner base particles each containing a binder resin and a colorant. When the viscosities of each of the toner particles measured at 100&#xb0; C. and 110&#xb0; C. by a flow tester heat-up method are represented by &#x3b7;(Pa&#xb7;s) and &#x3b7;(Pa&#xb7;s), respectively, an average variation in viscosity Arepresented by the following equation (1) satisfies the relationship of 0&#x2267;A&#x2267;&#x2212;0.064:=(log(&#x3b7;)&#x2212;log(&#x3b7;)/(110&#x2212;100); and&#x2003;&#x2003;(1)

Toner and method of producing toner

In a process cartridge having a latent-image-bearing member and a developing device having a developer-holding part and a developing member, at a vertical section which bisects in the process cartridge the surface of the latent-image-bearing member with which surface the developing member is brought into pressure contact, a developer agitation and transport member has at least two rotary agitation and transport members having rotating shafts falling at right angles with the vertical section. Where, at the vertical section, the area of the developer-holding part is represented by S1 and the area of the part corresponding to the movable region of the rotary agitation and transport member is represented by S2, the ratio of S2 to S1, S2/S1, is from 0.8 to 0.99; and the ratio of a long side Sa to a short side Sb, Sa/Sb, of a circumparallelogram having a minimum area in respect to the area S1 in the vertical section is from 1.5 to 3.0. The non-magnetic one-component developer contains at least a binder resin and a colorant and has a fluidity index of from 50 to 90 and a floodability index of from 45 to 96.

Integral-type process cartridge and developing-assembly unit including non-magnetic one-component toner

A toner suitable for use in electrophotography, etc., is composed of toner particles each containing a binder resin, a colorant and a wax component. The toner has a number-average particle size of 2-6 &mgr;m and a standard deviation in particle size of below 2.6 &mgr;m based on a number-basis distribution of circle-equivalent diameters, an average circularity of 0.970-0.995 and a standard deviation in circularity of below 0.030 based on a circularity frequency distribution, and a residual monomer content of at most 500 ppm. The toner particles have such a microtexture as to provide a particle cross section as observed through a transmission electron microscope (TEM) exhibiting a matrix of the binder resin and a particle of the wax dispersed in a discrete form in the matrix of the binder resin.

Toner for developing electrostatic images and image forming method

A toner is comprised of a binder resin, a colorant and a wax. The binder resin has a polycarbonate resin in an amount of from 0.1% by weight to 50.0% by weight and a resin other than the polycarbonate resin in an amount of from 50.0% by weight to 99.9% by weight, based on the weight of the binder resin. In molecular weight distribution as measured by gel permeation chromatography of tetrahydrofuran-soluble matter, the toner contains in an amount of 15.0% by weight or less based on the weight of the toner a component which has in its structure a repeating unit of the polycarbonate resin and is contained in components having a molecular weight of 1,000 or less.

Toner and image forming method

A toner having a good chargeability stable against an environmental change is formed of toner particles each comprising at least a binder resin, a colorant, a release agent and a sulfur-containing polymer, and an external additive. The toner particles contain 100 to 30,000 ppm by weight thereof of at least one stabilizer element selected from the group consisting of magnesium, calcium, barium, zinc, aluminum and phosphorus. The toner particles may preferably be produced by suspension polymerization of a monomer composition containing the sulfur-containing polymer in an aqueous medium containing a dispersion stabilizer having the stabilizer element.

Toner, toner production process and image forming method

Image forming method

A process for producing a polymerization toner, which comprises preparing a polymerizable-monomer composition which contains at least a polymerizable monomer and a colorant and does not contain any polymerization initiator, i) introducing the polymerizable-monomer composition into an aqueous medium to effect granulation, adding a polymerization initiator to the aqueous medium in the course of the granulation or after the granulation has been completed, or ii) adding a polymerization initiator in an aqueous medium, introducing the polymerizable-monomer composition into the aqueous medium to effect granulation, and then polymerizing the polymerizable-monomer composition having been granulated, to produce toner particles. In the process, the polymerization initiator is added in a specific time and a specific manner.

Process for producing polymerization toner

A toner contains at least a binder resin, a colorant, a wax and an aluminum compound, wherein the binder resin has an acid value of 1 to 40 mgKOH/g; the binder resin contains 2% to 50% by weight of tetrahydrofuran (THF) based on the weight of the binder resin; a tetrahydrofuran-soluble matter of the binder resin has a main peak in a molecular weight range of from 2,000 to 30,000 in a chromatogram by gel permeation chromatography (GPC); and the aluminum compound is a specific aluminum compound of substituted or unsubstituted benzilic acid.

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Suntoh-gun, Japan

Satoshi Handa