Ricoh Company, Ltd.

Jnc Corporation

Tsuneyasu Nagatomo

Satoshi Kojima

Osamu Uchinokura

Junichi Awamura

Hiroshi Yamashita

Masaki Watanabe

Naohiro Watanabe

Toyoshi Sawada

Naohito Shimota

Shinya Nakayama

Daisuke Ito

Daisuke Inoue

Tsuyoshi Sugimoto

Takamasa Hase

Minoru Masuda

Yukiko Iwasaki

Masayuki Ishii

Atsushi Yamamoto

Hiroshi Hosokawa

Tomoyuki Ichikawa

Takuya Seshita

Kenji Kikuchi

Hideki Sugiura

Hiroto Higuchi

Shinji Tamaki

Yasuaki Iwamoto

Kousuke Suzuki

Koichi Sakata

Takahiro Honda

Keiji Makabe

Satoshi Ogawa

Kohsuke Satoh

Shingo Sakashita

Tomoki Murayama

Daichi Hisakuni

Kenji Yoneda

Junichi Watanabe

Ryuta Chiba

Masaya Fukuda

Syouko Satoh

Tomomi Suzuki

Masana Shiba

Teruki Kusahara

Yuka Mizoguchi

Shinichi Wakamatsu

Kiwako Hirohara

Fumihiro Sasaki

Akihiro Kotsugai

Yasuo Asahina

Satoshi Mochizuki

Shunji Katoh

Hisashi Nakajima

Takuya Saito

Kazuoki Fuwa

Hiroshi Ikeguchi

Michiharu Suzuki

Hideyuki Santo

Mikio Yamahiro

Hyo Shu

Sonoh Matsuoka

Mamoru Hozumi

Akio Takei

Yohichi Kitagawa

Toshihiko Sugiyama

Tsukiko Takahashi

Shintaro Akiyama

Kenya Itoh

A toner includes a binding resin; and a metal crosslinking agent that forms a metal crosslinking with the binding resin. A measurement curve of a storage elastic modulus G' in a dynamic viscoelasticity measurement has a maximum value in a range of 100° C. or more.

Toner, toner storage unit, image forming apparatus and method of forming image

A toner is provided. The toner comprises colored particles and external additives present on surfaces of the colored particles. The colored particles each comprise a core and a shell layer. The core contains a crystalline resin, a non-crystalline resin, and a colorant. The shell layer contains a resin and has a thickness of from 30 to 130 nm. The external additives comprise a metal oxide and a silicon compound. An electronegativity X(A) of the metal oxide and an electronegativity X(Si) of the silicon compound satisfy a relation 0.5&#x2264;X(A)/X(Si)&#x2264;0.8. A proportion of an amount of the metal oxide directly adhered to the surfaces of the colored particles to a total amount of the metal oxide present on the colored particles is from 60% to 90% by mass.

Toner, method for manufacturing toner, developer, toner accommodating unit, image forming apparatus, and image forming method

An image forming apparatus is provided that includes: an image bearer; a charger; an irradiator; a developing device containing a toner; and a transfer device. The image bearer has a Martens hardness of from 185 to 250 N/m. The toner satisfies a relation 0.13&#x2264;X/Dn&#x2264;0.16, where X [&#x3bc;m] represents an average value of an amount of deformation of the toner by micro-indentation at when a load reaches 3.00&#xd7;10N at a loading rate of 3.0&#xd7;10N/sec under an environment of 32 degrees C. and 40% RH, and Dn [&#x3bc;m] represents a number average particle diameter of the toner. The toner contains an external additive comprising silica particles and particles composed mainly of strontium titanate. The particles composed mainly of strontium titanate further contain a third element M selected from the group consisting of La, Mg, Ca, Sn, and Si.

Image forming apparatus and image forming method

A toner including toner particles, each toner particle including a toner base particle, and inorganic particles, wherein the inorganic particles include particles of a fluorine-containing aluminium compound, and a liberation ratio of the inorganic particles is 10% or greater but 60% or less.

Toner, toner stored unit, developer, developer stored unit, and image forming apparatus

A toner including toner base particles each including a binder resin and a colorant, and external additive, wherein the toner satisfies conditions (a), (b), and (c) below:

Toner, image forming apparatus, image forming method, and process cartridge

A toner is provided. The toner includes toner particles each including a mother particle and external additive particles covering the mother particle. In a SEM image of the toner, toner particles having a ratio Sd/St of from 5% to 50% are present at a frequency of 15% or more, where Sd representing an area of a largest recessed portion D of each toner particle and St representing whole area of the toner particle, Sd and St determined from the SEM image magnified and binarized to discriminate recessed portions and projected portions of the toner particle from each other. An external additive coverage rate Ca at the largest recessed portion D is from 30% to 100%.

Toner, developer, toner storage unit, and image forming apparatus

An image forming method is provided. The method includes the steps of forming an electrostatic latent image on a photoconductor; developing the electrostatic latent image into a toner image with a toner; transferring the toner image onto a recording medium having a smoothness of 20 s or less; and fixing the toner image on the recording medium. The toner exhibits an adhesion force of 100 gf or more, where the adhesion force is the maximum value of a pull force between a layer of the toner and standard paper determined by a tacking test with a probe temperature of 140&#xb0; C.

Image forming method, toner, and image forming apparatus

A toner includes a base particle; and an external additive covering the base particle. The toner includes a tetrahydrofuran (THF)-insoluble component having a glass transition temperature determined from a DSC curve when heated for the second time of from &#x2212;50&#xb0; C. to 10&#xb0; C. and an average circularity not greater than 0.98, and satisfies the following relation:&#x2212;0.025&#xd7;&#x2266;1.80

Toner, developer, image forming apparatus, and process cartridge

A toner includes a base particle comprising a crystalline polyester resin; and an external additive which is a group of silica particles having a number-average particle diameter of from 0.01 &#x3bc;m to 0.11 &#x3bc;m on the surface of the toner. A number ratio of the silica particles having a circularity not less than 0.8 is 20% or more in the total number of the silica particles.

Toner, developer, and image forming apparatus

To provide a toner, which contains silica particles containing first silica particles, and second silica particles, wherein the toner is a toner produced by depositing the silica particles on surfaces of base particles, the first silica particles have an average primary particle diameter of 75 nm to 250 nm, the second silica particles have an average primary particle diameter of 10 nm to 50 nm, a mass ratio of the first silica particles to the base particles is 0.010 to 0.040, a mass ratio of the second silica particles to the base particles is 0.005 to 0.030, a liberation ratio of the silica particles from the toner by a ultrasonic vibration method is 5% by mass to 20% by mass, and an amount of particles having primary particle diameters of 30 nm or smaller in the silica particles librated from the toner by the ultrasonic vibration method is 20% by number or less.

Toner, developer and image forming apparatus

Provided is an electrostatic charge image developing toner, including: toner base particles including a polyester resin as a binder resin; and an external additive on the surface of the toner base particles. The external additive includes silica. The silica is produced by sol-gel method, and is aspherical. The percentage of change in the specific surface area of the toner when it is stored under high-temperature, high-humidity conditions is from 25% to 45%.

Electrostatic charge image developing toner

A toner set, including: a transparent toner including a binder resin a, a releasing agent a and no colorant; and one or more color toners, each including a binder resin b, a colorant b and a releasing agent b, wherein the binder resin a includes a non-crystalline resin &#x3b1; and a crystalline resin &#x3b1;, the binder resin b includes a non-crystalline resin &#x3b2; and a crystalline resin &#x3b2;, the releasing agent a has an average particle diameter as a long diameter of 0.2 &#x3bc;m to 2.0 &#x3bc;m, and there is a relationship of 1&#x3c;A/B&#x3c;1.5, where A is an area of the releasing agent a in a transparent toner cross-section from a surface thereof to a &#x2153;-depth of a volume-average particle diameter, and B is an area of the releasing agent b in a color-toner cross-section from a surface thereof to a &#x2153;-depth of a volume-average particle diameter.

Toner set, developer set, and image forming apparatus

A developing device, including: a developer bearing member, which is disposed opposite to an electrostatic latent image bearing member and which bears thereon a developer for developing an electrostatic latent image formed on the electrostatic latent image bearing member and conveys the developer to a developing region, wherein the developer includes a toner and a carrier, the toner containing: a toner base containing a binder resin and a colorant; and an external additive, wherein the external additive contains coalescent particles each made up of a plurality of coalescing primary particles, and wherein a work function Wc of the carrier and a work function Ws of the developer bearing member satisfy a relationship of the following formula (1):&#x2267;0.4 eV&#x2003;&#x2003;(1).

Developing device that suppresses hysteresis

Toner housing container includes: container body mountable on toner conveying device and housing toner supplied into toner conveying device; conveying portion provided in container body and conveying toner from longer direction one end of container body to other end at which container opening portion is provided; pipe receiving port provided at container opening portion and receiving conveying pipe fixed to toner conveying device; and uplifting portion to move toner conveyed by conveying portion toward toner receiving port of conveying pipe. Toner has loose apparent density of 0.28 g/cmto 0.53 g/cm. Container body includes protruding portion protruding from container body interior side of container opening portion toward one end. Uplifting portion includes uplifting wall surface extending from internal wall surface of container body toward protruding portion, and curving portion curving to conform to protruding portion. Protruding portion is present between curving portion and toner receiving port of inserted conveying pipe.

Toner housing container and image forming apparatus

An image forming apparatus includes: an image bearing member; a charger; an irradiator; a development device having an accommodation unit to accommodate toner to obtain a visible image; a transfer device; and a fixing device to fix the visible image transferred onto a recording medium. The fixing device having a fixing rotation member; and a pressure rotation member to form a nipping portion by contacting the fixing rotation member, wherein the surface pressure of the nipping portion is 1.5 kgf/cmor less, wherein the fixing rotation member has a Martens hardness of 1.0 N/mmor less at 23&#xb0; C., wherein the ratio of the projected area of a single particle of the toner onto the recording medium at 120&#xb0; C. to the projected area of a single particle of the toner onto the recording medium at 23&#xb0; C. is 1.60 or less.

Image forming apparatus

Growing community of inventors

Shizuoka, Japan

Tsuneyasu Nagatomo