Ricoh Company, Ltd.

Takahiro Honda

Junichi Awamura

Osamu Uchinokura

Yohichiroh Watanabe

Fumihiro Sasaki

Yoshihiro Norikane

Naohito Shimota

Masami Tomita

Hiroto Higuchi

Shigeru Emoto

Shinichiro Yagi

Toshiki Nanya

Kazumi Suzuki

Daisuke Inoue

Shinji Ohtani

Hiroshi Yamada

Hiroyuki Fushimi

Masaki Watanabe

Yasuo Asahina

Hisashi Nakajima

Satoshi Ogawa

Tomomi Suzuki

Daisuke Ito

Satoshi Kojima

Hideki Sugiura

Yasuaki Iwamoto

Tomoyuki Ichikawa

Shinya Nakayama

Tsuyoshi Sugimoto

Koichi Sakata

Akihiro Kotsugai

Masayuki Ishii

Shinya Tanaka

Hiroshi Yamashita

Shinji Aoki

Naohiro Watanabe

Tsuneyasu Nagatomo

Maiko Kondo

Syouko Satoh

Satoshi Mochizuki

Yasutada Shitara

Teruki Kusahara

Hyo Shu

Tomoko Utsumi

Mamoru Hozumi

Ryuta Chiba

Ryuuta Yoshida

Kiwako Hirohara

Masami Okamoto

Masato Iio

Shingo Sakashita

Takayuki Itoh

Masaru Ohgaki

Rintaro Takahashi

Kaori Hemmi

Tadao Takikawa

Tomoki Murayama

Tomoyuki Satoh

Yukio Tabata

Andrew Mwaniki Mulwa

Yasuo Kamada

Akio Takei

Shuuichi Endoh

Yuko Sekiguchi

Kenta Kashiwagi

Ayumi Satoh

Ken Umehara

Yoshihisa Hara

Tsukiko Takahashi

Koshi Sato

Naohito Bell Shine Takehara A-103 Shimota

Tomoyuki Dai6 Sumika Bldg 206 Ichikawa

Naohito Shimoda

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 includes an image bearer, a developing unit configured to develop a latent image formed on the image bearer with a toner to form a toner image, and a transfer member including a contact area that comes in contact with the image bearer. The toner image is primary transferred from the image bearer to the transfer member. A speed difference between the image bearer and the transfer member at the contact area is 0.1% or greater but 0.8% or less. The toner has an average circularity of 0.971 or greater but 0.986 or less and a shape factor SF-2 of 110 or greater but 119 or less. The speed difference is represented by the following formula:Speed difference [%]={(1&#x2212;2)/2}&#xd7;100&#x2003;&#x2003;[Speed difference]where V1 is a linear speed of the image bearer, and V2 is a linear speed of the transfer member.

Image forming apparatus and image forming method

An image forming apparatus including a developing device and a fixing device is provided. The fixing device includes a fixing rotator having a fixing surface, an opposing rotator opposing the fixing rotator to form a nip portion therebetween, and a fixing surface reformer having an abutting layer to abut the fixing surface. The abutting layer contains abrasive grains having an average grain size of 2.0-6.5 &#x3bc;m on a surface which abuts the fixing surface. The toner comprises a crystalline polyester resin and exhibits G' (storage elastic modulus) of 1.0&#xd7;10Pa or lower at 70&#xb0; C. in a temperature rising in a viscoelasticity measurement, G&#x2032; of 1.0&#xd7;10Pa or higher at 70&#xb0; C. in a temperature falling in the viscoelasticity measurement, and an endothermic peak indicating an amount of heat absorption of from 2.0 to 8.0 J/g, derived from the crystalline polyester resin, in a first temperature rising in DSC.

A toner includes a binder resin; a release agent; and two or more inorganic fine particles as external additives. At least one of the inorganic fine particles is silica. When an ultrasonic oscillation is applied to a dispersion including the toner and a dispersant and a rate of the silica releasing from the toner is 20% based on total silica, an application energy of the ultrasonic oscillation is from 8 to 14 kJ, and from 70 to 130 kJ when the rate of the silica releasing from the toner is 50%.

Toner, developer, toner housing unit and image forming apparatus

A toner including: a binder resin containing a non-crystalline resin and a crystalline resin; a colorant; and, a releasing agent, wherein the releasing agent has a melting point of 55&#xb0; C. to 80&#xb0; C., and wherein the toner satisfies the following Expressions 1 and 2: (Expression 1): 20,000 Pa&#xb7;s&#x2266;G&#x2266;50,000 Pa&#xb7;s; and (Expression 2): (G/G)/(G/G) 1.00, where Gis a storage modulus, Gis a loss modulus, Gis a storage modulus and Gis a loss modulus, and the storage modulus Gand the loss modulus Gare measured at 80&#xb0; C. when the toner is heated from 70&#xb0; C. to 150&#xb0; C. and the storage modulus Gand the loss modulus Gare measured at 80&#xb0; C. when the toner heated to 150&#xb0; C. is cooled to 70&#xb0; C.

Toner, developer and image forming apparatus

A method for producing resin particles, including ejecting a liquid containing at least a resin in the form of droplets from a droplet ejecting unit having a plurality of holes provided in a part of a flow channel for feeding the liquid containing at least a resin, and drying and solidifying the ejected droplets so as to obtain the resin particles, while the ejected droplets are transported by a primary transport air flow flowing in the direction in which the droplets are ejected, wherein the ejected droplets are further transported by a secondary transport air flow which transports the ejected droplets in a different direction from a direction in which the primary transport air flow flows, and wherein a smaller angle of angles formed between a velocity vector of the primary transport air flow and a velocity vector of the secondary transport air flow is less than 120 degrees.

Method for producing toner for developing electrostatic image and apparatus for producing resin particles

A toner including: toner base particles; and an external additive, the toner base particles each comprising a binder resin and a colorant, wherein the external additive comprises non-spherical particles and spherical particles, wherein the non-spherical particles are each a secondary particle in which spherical primary particles are coalesced together, and wherein the non-spherical particles and the spherical particles in the external additive satisfy a relationship expressed by the following formula (1):3(%)&#x3c;(%)&#x2003;&#x2003;Formula (1) where Ca is greater than 10% but smaller than 20% and Cb is greater than 40% but smaller than 70%, and Ca and Cb are values given by: 

Toner, two-component developer and image forming apparatus

A toner for developing an electrostatic image, including: toner base particles each including a binder resin and a releasing agent; and inorganic fine particles, wherein the toner includes the inorganic fine particles as an external additive on a surface of the toner base particle, wherein the toner base particles have a BET specific surface area of 2.5 m/g to 5.0 m/g, and wherein the inorganic fine particles comprise inorganic fine particles (A) which are each a secondary particle where a plurality of primary particles are coalesced together.

Toner for developing electrostatic image, two-component developer and image forming apparatus

To provide a toner, which contains: toner base particles each containing a binder resin and a colorant; and an external additive containing inorganic particles and fatty acid metal salt particles, wherein the inorganic particles contain at least hydrophobic silica particles, wherein a liberation ratio Ya of the hydrophobic silica particles from the toner is 1% by mass to 20% by mass, and wherein a libration ratio Yb of the fatty acid metal salt particles from the toner is 30% by mass to 90% by mass.

Toner and image forming apparatus

To provide a toner, which contains a binder resin, a colorant, and a releasing agent, wherein the binder resin contains a low molecular weight resin component, where the low molecular weight resin component has a resin softening coefficient (A), represented by the following formula (1), satisfying A&#x3e;0.165, and has storage elastic modulus (dyne/cm) G'(Tfb) satisfying G&#x2032;(Tfb)&#x2266;1&#xd7;10where Tfb is a flow onset temperature (&#xb0; C.) of the low molecular weight resin component as measured by a capillary rheometer:=|[(1)&#x2212;ln&#x2032;(2)]/(1&#x2212;2)|&#x2003;&#x2003;Formula (1)(where T1 is temperature (&#xb0; C.) at which storage elastic modulus G&#x2032;(r1) is 1&#xd7;10(dyne/cm) and T2 is temperature (&#xb0; C.) at which storage elastic modulus G&#x2032;(r2) is 1&#xd7;10(dyne/cm) as measured by means of a viscoelasticity measuring device with measuring frequency of 1 Hz, and measuring distortion of 1 deg; and | | represents an absolute value.).

Toner for electrostatic charge development

A toner produced by a method including dissolving or dispersing toner components comprising a resin, a colorant, and a release agent in a solvent to prepare a toner components liquid, discharging the toner components liquid from multiple nozzles provided on a thin film by vibrating the thin film by a mechanical vibration unit to form liquid droplets, and drying the liquid droplets into solid particles of the toner. The particle diameter distribution that is a ratio of a weight average particle diameter to a number average particle diameter of the toner is between 1.00 and 1.15, and a weight average particle diameter of the release agent in the toner is between 1% and 30% of an aperture diameter of the nozzle.

Toner, method of producing toner, and image forming method

A method for producing a toner, including ejecting a toner composition liquid containing at least a resin and a colorant periodically from a plurality of nozzles into a chamber using a vibration unit, so as to form droplets in a gas phase; and solidifying the droplets, wherein the droplets are transported by transport air flow selected from at least one of vertical downward air flow and rotational air flow, and the method can prevent toner particles from aggregation.

Method and apparatus for producing toner

To provide a toner A containing: base particles, each containing polyester, microcrystalline wax, and a colorant; and spherical silica particles having an average primary particle diameter of 100 nm to 150 nm, wherein the microcrystalline wax has an onset temperature of 45&#xb0; C. to 60&#xb0; C. as determined by DSC, and a carbon number distribution of 25 to 55.

Toner, method for forming toner, developer, and image forming method

A toner including a core particle, an inner shell layer covering the core, and an outer shell layer covering the inner shell layer is provided. The core particle includes a resin P. The inner shell layer includes fine particles of a resin A. The outer shell layer includes fine particles of a resin B. The toner satisfies the following formulae (1) to (3):4.5&#x2266;&#xbd;()&#x2212;()&#x2266;14&#x2003;&#x2003;(1)20&#x2266;&#xbd;()&#x2212;()&#x2266;40&#x2003;&#x2003;(2)23.5&#x2266;&#xbd;()&#x2212;()&#x2266;40&#x2003;&#x2003;(3)wherein T&#xbd;(P), T&#xbd;(A), and T&#xbd;(B) represent &#xbd; method temperatures of the resins P, A, and B, respectively, and Tfb(P), Tfb(A), and Tfb(B) represent flow beginning temperatures of the resins P, A, and B, respectively, and wherein the &#xbd; method temperatures and the flow beginning temperatures are measured by a flowtester.

Toner

A method of preparing a toner, including periodically dripping and discharging droplets of a toner constituent liquid comprising a resin and a colorant with a dripper comprising a thin film comprising plural nozzles configured to discharge the droplets, and an electromechanical converter configured to oscillate the thin film; and solidifying the droplets to form toner particles, wherein the nozzle has an aperture discharging the droplet, having a circular or an ellipsoidal cross-sectional shape and cross-sectional area smaller than a cross-sectional area of another aperture contacting the toner constituent liquid.

Toner preparation method and apparatus, and toner prepared thereby

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Fujinomiya, Japan

Takahiro Honda