Canon Kabushiki Kaisha

Yuji Moriki

Hiroaki Kawakami

Michihisa Magome

Shinya Yachi

Satoshi Handa

Tatsuya Nakamura

Yushi Mikuriya

Keiji Komoto

Emi Tosaka

Kenichi Nakayama

Takeshi Kaburagi

Koji Inaba

Kenji Okado

Tatsuhiko Chiba

Ryoichi Fujita

Katsuyuki Nonaka

Yasuhiro Hashimoto

Yasushi Katsuta

Kiyokazu Suzuki

Tetsuya Kobayashi

Yoshihiro Nakagawa

Wakashi Iida

Atsuyoshi Abe

Kohei Matsuda

Shinya Yamamoto

Kazumi Yoshizaki

Shinichi Agata

Masato Koyanagi

Kohji Inaba

Kentarou Kawata

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.

Toner

A toner includes toner particles containing at least a binder resin and a colorant, and inorganic fine particles. The shape factor SF-1 of the toner particles is in a specific range. The toner has a storage elastic modulus at 140&#xb0; C., G' (140&#xb0; C.), in a specific range the toner comes to have a viscosity of 1.0&#xd7;10Pa&#xb7;s according to a flow tester heating method at a temperature of from 115&#xb0; C. or more to less than 130&#xb0; C.

Toner, and image forming method

A developing apparatus including: a developer carrying member for carrying a developer, the developer carrying member being provided with an elastic layer and adapted to develop, with a developer, an electrostatic image formed on an image bearing member; wherein the developer includes a toner, the toner has a shape factor SF-1 of 100 or more but less than 130, the toner has a storage modulus G' (140&#xb0; C.) at 140&#xb0; C. of 2.0&#xd7;10dN/mor more but less than 2.0&#xd7;10dN/m, the toner has a temperature, when the toner has a viscosity of 1.0&#xd7;10Pa&#xb7;s in a flow tester temperature elevation method, of 115&#xb0; C. or more but less than 130&#xb0; C., and, in a surface roughness of the developer carrying member, a center-line mean roughness Ra, a ten-point mean roughness Rz and a mean spacing Sm of irregularities satisfy following relationships (1): 

Developing apparatus

In a non-magnetic toner having non-magnetic toner particles containing at least a binder resin and a colorant, and an inorganic fine powder, the non-magnetic toner particles contain at least one ether compound having a specific structure, and the ether compound is in a content of from 5 ppm to 1,000 ppm.

Non-magnetic 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 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

An electrophotographic toner is formed of toner particles each comprising at least a binder resin, a colorant and a release agent, and a low-crystalline aromatic metal compound present at surfaces of the toner particles. The toner has an average circularity of at least 0.955, and the low-crystalline aromatic metal compound has an X-ray diffraction characteristic free from peaks exhibiting a measurement intensity of at least 10000 cps and a half-value half-width of at most 0.3 deg. in a range of measurement angles 2&thgr; of 6 to 40 deg. Because of the low crystallinity, the aromatic metal compound is uniformly applied onto the toner particle surfaces to stabilize the chargeability and transferability of the toner.

Toner and image forming method

A toner is disclosed which has toner particles and an external additive. The toner has (a) in circularity distribution of particles measured with a flow type particle image analyzer, an average circularity of from 0.920 to 0.995, containing particles with a circularity of less than 0.950 in an amount of from 2% by number to 40% by number; and (b) a weight-average particle diameter of from 2.0 .mu.m to 9.0 .mu.m as measured by Coulter method. The external additive has, on the toner particles, at least (i) an inorganic fine powder (A) present in the state of primary particles or secondary particles and having an average particle length of from 10 m.mu.m to 400 m.mu.m and a shape factor SF-1 of from 100 to 130 and (ii) a non-spherical inorganic fine powder (B) formed by coalescence of a plurality of particles and having a shape factor SF-1 of greater than 150. Also, a two-component developer and an image forming method, using the toner, are disclosed.

Toner, two-component developer and image forming method

A toner is comprised of toner particles containing at least a binder resin and a colorant, and an external additive fine powder. The toner particles have a specific circularity distribution and a specific particle size distribution. The external additive fine powder has an inorganic fine powder having as primary particles a specific number-average particle length, and a non-spherical inorganic fine powder formed by coalescence of particles and having a specific shape factor and a specific number-average particle length.

Toner, two-component developer, image forming method and apparatus unit

In an image forming method for forming multi-color images or full-color images, first to third or fourth toners are used, and the amount of cross-linking agent contained in each of the toners becomes larger in the order of the toners laid on a recording sheet. Each of the toners has a color different from the others, the color selected from yellow, cyan, magenta and black.

A toner for developing electrostatic images is provided. THF-soluble matter of the toner has, in molecular-weight distribution as measured by GPC, at least one peak in the molecular weight region of from 1,000 to less than 2,000 and at least one peak in the molecular weight region of from 2,000 to 300,000, and has a weight average molecular weight of from 90,000 to 2,000,000. Molecular weight integral value T in the molecular weight region of 800 or more, molecular weight integral value L in the molecular weight region of from 2,000 to 5,000 and molecular weight integral value H in the molecular weight region of 300,000 or more satisfy the relationship :

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Numazu, Japan

Yuji Moriki