Ricoh Company, Ltd.

Minolta Company, Ltd.

Konica Minolta Business Technologies, Inc.

Masayuki Hagi

Yoshihiro Mikuriya

Hideaki Yasunaga

Masahide Inoue

Takeshi Arai

Junichi Tamaoki

Yoshitaka Sekiguchi

Kazuoki Fuwa

Katsunori Kurose

Hiroaki Katoh

Takuya Kadota

Atsushi Yamamoto

Hiroaki Kato

Megumi Aoki

Hiroyuki Fukuda

Yoshimichi Ishikawa

Kenichi Kido

Minoru Nakamura

Tetsuo Sano

Tsuyoshi Nozaki

Satoshi Ogawa

Chiyoshi Nozaki

Hiroyuki Murakami

Yoshiyuki Shimizu

Ichiro Demizu

Masahiro Anno

Naoki Nakatake

Yoshie Iwakura

Tomohiro Fukao

Manabu Hamada

Tomoharu Miki

Tetsushi Sakuma

Hidekazu Shono

Yoshikazu Nishihara

Miyoko Goto

Yoko Osawa

A toner including an amorphous resin (R), a crystalline material (A) which is compatible with the amorphous resin (R) and has a melting point of 80&#xb0; C. or lower, a resin (I) which is different from the amorphous resin (R), and a colorant, wherein the crystalline material (A) is capsulated by the resin (I) and the capsulated crystalline material (A) is present in the amorphous resin (R).

Toner, and method for producing the same

A toner containing core particles each containing at least a resin A having a polyester skeleton and a colorant; and vinyl resin fine particles each of which encapsulates a resin B having at least a polyester skeleton and an endothermic peak measured by differential scanning calorimeter (DSC) at 40&#xb0; C. to 110&#xb0; C., wherein the vinyl resin fine particles are attached onto each of the core particles.

Toner and method for producing the same

A non-magnetic toner, including a binder resin; a wax present dispersing in the toner in the shape of a particle; and a colorant, wherein the wax having a particle diameter not less than 2.0 &#x3bc;m and less than 3.0 &#x3bc;m is not less than 20% and less than 40% by number based on total number thereof; the wax has a mode value not less than 1.5 &#x3bc;m and less than 2.0 &#x3bc;m in a frequency distribution of 0.1 &#x3bc;m width; and the following relationship is satisfied:45&#x3c;&#x3c;62wherein X represents a softening point (&#xb0; C.) of the toner; Y represents a volume-average particle diameter (&#x3bc;m) of the toner; and Z represents a total parts by weight of the wax included in 100 parts by weight of the toner.

Toner for non-magnetic one-component developer, method of preparing the toner, developer and image forming method

An image forming method, including charging the surface of an electrostatic latent image bearer by a charger; irradiating the surface of the electrostatic latent image bearer to form an electrostatic latent image thereon; developing the same with a toner to form a toner image; transferring the toner image onto a recording medium; and fixing the toner image thereon, wherein the charger is a charging roller contacting the electrostatic latent image bearer to charge the same, having a ten-point surface roughness of 5 to 30, and the toner includes a binder resin, a colorant, a release agent and an external additive including a composite oxide including titanium oxide in an amount of 80 to 95% by weight and silicon oxide, having a core-shell structure formed of a core including the titanium oxide and a shell including the silicon oxide and has a BET specific surface area of 50 to 100 m/g.

Image forming method, image forming apparatus and process cartridge

A developing device including a developing roller facing an image bearing member and a toner layer thickness control member to control an amount of a toner adhered to the developing roller, so that an electrostatic latent image formed on the image bearing member is developed with the toner to form a toner image. The following relationships are satisfied: 0.08&#xd7;10&#xd7;Dv&#x3c;Ra&#x3c;0.18&#xd7;10&#xd7;Dv, 2.0&#x3c;(Ra/RSm)&#xd7;100&#x3c;4.0, and 8&#x3c;Rz&#x3c;15, where Dv (&#x3bc;m) is a volume average particle diameter of the toner, Ra (&#x3bc;m) is an arithmetical mean roughness of the developing roller in a longitudinal direction, Rz (&#x3bc;m) is a ten-point mean roughness of the developing roller in a longitudinal direction, and RSm (&#x3bc;m) is a mean length of roughness curve elements of the developing roller.

Developing device, and image forming method and process cartridge using the developing device

A toner for electrostatic charge development is provided where the toner comprises a colorant and a resin and contains an organic boron compound represented by a following chemical formula (A) as a charge controlling agent, further the toner is treated with an inorganic fine particle and at least one of the inorganic particles is a magnesium silicate compound represented by a following general formula [2] is provided. 

Toner and image forming method

To provide a pulverized toner excellent in the releasing ability and cleaning ability, and an image-forming apparatus for one-component developer, and a process cartridge using the pulverized toner. The pulverized toner contains a toner base particle containing at least a binder resin, a colorant, and a releasing agent, the mass ratio of the releasing agent to the binder resin is 3.0% to 6.0%, the adhesive force among the pulverized toners at 25&#xb0; C. to 55&#xb0; C. is 20 g to 80 g, and the pulverized toner is used for the image-forming apparatus for one-component developer containing the cleaning unit configured to dispose an elastic blade adjacent to the surface of the image bearing member so as to clean the surface.

Pulverized toner

An image developer using a one-component developer, Including a developing roller visualizing an electrostatic latent image formed on an image bearer with a pulverized toner; and a feed roller feeding the pulverized toner to the developing roller while contacting thereto, wherein the pulverized toner includes a parent toner; a wax; and an external additive comprising an additive having a number-average particle diameter of from 20 to 60 nm and adhering to the surface of the parent toner at an adherence strength of from 50 to 70%, and wherein the following relationships (1) to (3) are satisfied:4.70&#x3c;LogR&#x3c;5.70&#x2003;&#x2003;(1)8.00&#x3c;LogZ&#x3c;10.70&#x2003;&#x2003;(2)&#x2212;6.25*Log+37.5&#x3c;Log&#x3c;&#x2212;6.25*Log+45.6&#x2003;&#x2003;(3)wherein R represents a resistivity of the developing roller and Z represents an impedance of the pulverized toner.

Image developer using one-component developer

A toner useful for an oilless fixing method, includes a binder resin; a colorant; and 2.0 to 4.5% by weight of a wax which is soluble in n-hexane, based on a total weight of the toner, wherein the wax is dispersed in the toner, the wax forming wax domain particles (DA) comprising wax domain particles (DS) exposed at a surface of the toner and wax domain particles (DI) encapsulated in the toner and not exposed at the surface of the toner, wherein a weight of the DS is greater than a weight of the DI, wherein the toner from which the DS have been eluted with n-hexane comprises vestigial concavities having an area of 0.01 &#x3c0;&#x3bc;mor more on the surface of the toner in an amount of from 1 to 7 pcs/4 &#x3bc;m, and wherein 60% or more by number of the DA having a particle diameter of 200 nm or more have a spindle or cylindrical shape having an aspect ratio of 4 or more.

Toner, and oilless fixing method and process cartridge using the toner

A full-color toner kit including yellow, magenta, and cyan toners each including a benzimidazolone, a naphthol, and a copper phthalocyanine colorants, respectively, and resins (A) and (B) each of which having a polyester skeleton and containing a wax, and a resin (C) having a polyester skeleton and containing no wax. Each of the toners has a softening point of from 125&#xb0; C. to 135&#xb0; C. The following relationships are satisfied: Ts(A)&#x3c;Ts(B), Ay+5&#x2266;Am&#x2266;Ay+15, and Ac+5&#x2266;Am&#x2266;Ac+15, wherein Ts(A) and Ts(B) (&#xb0; C.) each represent softening points of the resin (A) and (B), respectively, and Ay, Am, and Ac each represent ratios (% by weight) of the amount of the resin (A) to total amount of the resins (A) and (B) in the yellow, magenta, cyan toners, respectively.

Full-color toner kit, process cartridge, and image forming method

A toner including toner particles including a resin, a colorant, a wax, and a charge controlling agent, and an external additive, wherein the toner satisfies the relationships (1) 0.15&#xd7;Q&#x2212;2&#x2266;T&#x2266;0.15&#xd7;Q&#x2212;0.15, and (2) 1.0&#x2266;T&#x2266;2.5, wherein Q represents the charge of the toner in units of &#x3bc;C/g, and T represents the torque of the toner in units of mN&#xb7;m determined by a method using a cone-shaped rotor while controlling a space ratio of the toner at 58%. A developer including the toner and a carrier. An image forming apparatus including an image bearing member, a transfer device, a fixing device and a double side image forming unit, and using the toner, wherein the receiving material includes moisture in an amount of not greater than 5% by weight after the toner image on the first side is fixed.

Toner, developer including the toner, and image forming method and apparatus using the toner

A developing device including a developer bearing member configured to feed a developer to an image bearing member; a developer supplying member, which is contacted with the developer bearing member at a first nip while opposed thereto and which is configured to supply the developer to the developer bearing member; and a developer layer forming member, which is contacted with the developer bearing member at a second nip located on the downstream side from the first nip relative to the rotation direction of the developer bearing member to form the layer of the developer on the developer bearing member, wherein the developer is a nonmagnetic one component developer, and the distance between the front edge of the second nip and the rear edge of the first nip relative to the rotation direction of the image bearing member is greater than 0.8 mm and less than 2.0 mm.

Developing device, developer therefor, and image forming method and apparatus, and process cartridge using the developing device

A single component development device including a toner including a resin, a coloring agent, a wax, a charge control agent and an inorganic particulate, a development roller to bear the toner on the surface of the development roller and transfer the toner to an image bearing member and a thin layer forming member to regulate a thickness of the layer of the toner while in contact with the surface of the development roller via the toner borne thereon, wherein a regulating pressure A between the thin layer forming member and the development roller is from 25 to 60 (N/m), a content Z (weight %) of the charge control agent satisfies the following relationship (1) and an average dispersion particle diameter D (nm) of the charge control agent satisfies the following relationship (2):0.029&#xd7;&#x2212;0.150&#x3e;&#x3e;0.013&#xd7;&#x2212;0.013&#x2003;&#x2003;Relationship (1)&#x3c;6.3&#xd7;&#x2212;106.3&#x2003;&#x2003;Relationship (2).

Single component development device, process cartridge and toner

A non-magnetic toner including a binder resin including a first resin, a second resin, a third resin; a colorant; and a wax, wherein the first resin is a hybrid resin including an amorphous condensation polymerization unit and a radical polymerization unit in its molecular frame, and the second and third resins are non-hybrid resins including condensation polymerization units, wherein each of the first, second and third resins has a glass transition temperature (Tg) and a softening point (Tm) satisfying the following relationships:Tg of first resin&#x3c;Tg of second resin&#x3c;Tg of third resin, which is from 70 to 80&#xb0; C., andTm of second resin&#x3c;Tm of third resin&#x3c;Tm of first resin, and

Non-magnetic toner for one-component development and method of preparing the toner, and image developer, image forming apparatus, process cartridge and image forming method

A toner including toner particles including a binder resin, a colorant and a release agent, and an external additive including a first particulate inorganic material having a formula of MgSiOwhere each of x and y is an integer, and a number average secondary particle diameter of from 0.02 &#x3bc;m to 2 &#x3bc;m, wherein the first atomic ratio (Mg/Si)s in a surface portion of the first particulate inorganic material is not greater than (preferably less than) the second atomic ratio (Mg/Si)e in the entire first particulate inorganic material. Alternatively, a toner including toner particles including a binder resin and a colorant, and an external additive which includes a particulate inorganic material having a formula of MgSiOwhere each of x and y is an integer and which has a surface treated with a fatty acid.

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Minoo, Japan

Masayuki Hagi