Ricoh Company, Ltd.

Hyo Shu

Minoru Masuda

Masami Tomita

Hiroshi Yamashita

Mitsuo Aoki

Yasutada Shitara

Kumi Hasegawa

Yasuaki Iwamoto

Hisashi Nakajima

Hiroyuki Kishida

Shinya Nakayama

Osamu Uchinokura

Satoshi Ogawa

Takahiro Honda

Saori Yamada

Ryuuta Yoshida

Masaki Watanabe

Daisuke Ito

Daisuke Inoue

Tsuyoshi Sugimoto

Satoshi Kojima

Naohiro Watanabe

Hideki Sugiura

Ryota Inoue

Fumihiro Sasaki

Junichi Awamura

Katsunori Kurose

Masayuki Ishii

Hiroyuki Fushimi

Naohito Shimota

Tomomi Suzuki

Yoshitaka Yamauchi

Tsuneyasu Nagatomo

Masahide Inoue

Akihiro Kaneko

Masana Shiba

Teruki Kusahara

Tomoko Utsumi

Shinya Hanatani

Wakana Itoh

Hiroki Ishii

Syouko Satoh

Ken Umehara

Koshi Sato

A toner including a strontium titanate powdery material as an external additive, the strontium titanate powdery material including Si-containing particles on a surface of the strontium titanate powdery material, the Si-containing particles having a number average circle equivalent diameter of 5 nm or more but 15 nm or less.

Toner, toner stored container, developer, developing device, process cartridge, and image forming apparatus

A toner comprising base particles and external additive particles covering the base particles is provided. The base particles comprise a binder resin and a colorant. The external additive particles comprise at least one member selected from the group consisting of fluorine-containing aluminum hydroxide, fluorine-containing boehmite, and fluorine-containing pseudoboehmite.

Toner, toner accommodating container, developer, developing device, process cartridge, image forming apparatus, and image forming method

An image forming apparatus including an image forming device forming a toner image on a recording material, and a fixing device including an endless fixing belt feeding the recording material at a speed of 400 to 1,700 mm/sec while heating to fix the toner image thereon. The fixing belt has a rubber layer located on a substrate and having thickness of 400 &#x3bc;m to 700 &#x3bc;m, and a fluorine-containing resin layer located on the rubber layer and having thickness of 2 &#x3bc;m to 20 &#x3bc;m. The toner includes a release agent including a microcrystalline wax and/or a synthetic ester wax, and a binder resin including a crystalline polyester and an amorphous polyester. The ratio (W/R) of the height (W) of the third falling peak of the crystalline polyester to the height (R) of the maximum rising peak of the amorphous polyester in the FT-IR spectrum of the toner is 0.045 to 0.850.

Image forming apparatus and method, and toner, developer and process cartridge for forming image

A toner set, including: at least one chromatic toner containing a colorant; and a transparent toner containing no colorant, wherein the chromatic toner and the transparent toner each include a releasing agent and a binder resin, and wherein an amount of a tetrahydrofuran insoluble matter in the transparent toner is smaller than an amount of a tetrahydrofuran insoluble matter in the chromatic toner.

Toner set, developer set, and image forming apparatus

An image forming apparatus having a system speed of from 400 to 1,700 mm/sec, including a latent image bearer; an image developer developing the latent image with two-component developer including a toner and a carrier; a transferer, a toner concentration detector; a toner feeder; and a controller, wherein the toner comprises a release agent and a binder resin including a crystalline polyester resin and an amorphous resin, wherein a ratio (W/R) of a maximum rising peak height (W) of the crystalline polyester resin to a maximum rising peak height (R) of the amorphous resin, which are observed respective infrared absorption spectra when measured by an IR spectroscopy using a Fourier transform infrared spectroanalyzer, is from 0.22 to 0.55.

Image forming apparatus and image forming method

A toner including toner particles including a binder resin containing at least one polyester resin comprising an inorganic tin (II) compound and an external additive including a particulate inorganic material having a volume average particle diameter greater than 70 nm and less than 300 nm. The binder resin preferably includes a polyester resin having a weight average molecular weight of from 5,000 to 50,000 and another resin having a weight average molecular weight of from 200,000 to 400,000. A developer including the toner; and a developing device, an image forming apparatus and a process cartridge, which form toner images using the toner are also provided.

Toner, developer including the toner, and developing device and image forming apparatus using the toner

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

An image forming apparatus including a latent electrostatic image bearing member, a latent electrostatic image forming unit, a developing unit, a transfer unit and a fixing unit, wherein the fixing unit includes rotatable heating member heating the recording medium having the unfixed visible image, rotatable pressing member coming into contact with the rotatable heating member to form a nip portion, and an air separation member separating the recording medium from the rotatable heating member by air, the toner including toner base particles each including binder resin and releasing agent, the binder resin including crystalline polyester resin and non-crystalline resin, and ratio of W/R being 0.045 to 0.85, where W denotes peak height in spectrum of the crystalline polyester resin, R denotes peak height in spectrum of the non-crystalline resin, and each of the spectra is measured by total transmission method (KBr method) using Fourier transform infrared (FT-IR) spectrometer.

A toner, wherein a binder resin contains a polyester resin (A) produced by polycondensing an alcohol component with a carboxylic acid component which contains a rosin compound in an amount of 5% by mass or more of the total amount by mass of the alcohol component and the carboxylic acid component, and a polyester resin (B) produced by polycondensing an alcohol component containing an alkylene oxide adduct of bisphenol A represented by General Formula (1) given below with a carboxylic acid component, and wherein the toner contains abietic acid in an amount of 0.01% by mass to 1% by mass: 

Toner and developer

A toner containing at least a binder resin, releasing agent, and colorant, wherein the binder resin contains polyester resin (A), polyester resin (B), and polyester resin (C), which is prepared by condensation-polymerizing (i) an alcohol component containing an alkylene oxide adduct of bisphenol compound and (ii) a carboxylic acid component; at least one of the polyester resin (A) and polyester resin (B) is a polyester resin prepared by condensation-polymerizing (i) the alcohol component substantially composed of only aliphatic alcohol and containing 1,2-propanediol in an amount of 65 mole % or more of a divalent alcohol component and (ii) the carboxylic acid component; and a softening point Tm(A) of the polyester resin (A) is 10 C or more higher than Tm(B) of the polyester resin (B), and the absolute difference between Tm(C) of the polyester resin (C) and the Tm(B) is 5&#xb0; C. or less.

A toner is provided including a mother toner including a crystalline polyester resin, an amorphous resin, and a wax, and an external additive in an amount of from 0.30 to 0.55 parts by weight based on 100 parts by weight of the mother toner. The toner satisfies the following equation 0.36&#x2266;(2.77&#xd7;C/R+1.97&#xd7;W/R)/X&#x2266;1.85, wherein each of C, W, and R represents a height of an absorbance peak specific to the crystalline polyester resin, the wax, and the amorphous resin, respectively, measured by a FT-IR ATR method, and X represents an amount (parts by weight) of the external additive. An image forming method and apparatus using the toner are also provided.

Image forming method, image forming apparatus, and toner

An image forming method including forming an electrostatic latent image on a photoreceptor; developing the latent image with a developer including a toner using a center-feed developing device to form a toner image; transferring the toner image onto a receiving material; and fixing the toner image using a fixing member coated with silicone oil. The toner includes at least a binder resin; a colorant; and a quaternary ammonium salt having a specific formula, wherein when the toner is dispersed in ethanol using ultrasonic waves, the dispersion has a turbidity of from 0.4 to 1.0 when the turbidity is determined using a haze meter. An image forming apparatus including a photoreceptor; a center-feed developing device using a developer including the toner; a transferring device; a fixing device using a fixing member coated with silicone oil; and a cleaner for the photoreceptor.

Image forming method and image forming apparatus

A full color toner containing a binder resin, a release agent and a colorant is provided, wherein the binder resin contains a polyester resin containing a hybrid resin containing one or more vinyl group polymer units and one or more polyester units, and wherein the content A of the hybrid resin and the content B of the release agent satisfy the following relationship: B/2&#x2266;A&#x2266;3B.

Full color toner, and its use in electrophotography methods and apparatus

An image forming apparatus including a fixing device to fix a toner image on a recording medium including a heat roller and an oil applicator to apply a silicone oil to the heat roller, having a system speed of from 500 to 1700 mm/sec, and using a toner including a binder resin including a crystalline polyester resin and an amorphous polyester resin; a fatty acid amide compound; and a colorant, wherein a ratio (W/R) of a height (W) of a peak at a wavenumber of 1638 cm, specific to the fatty acid amide compound, to a height (R) of a peak at a wavenumber of 829 cm, specific to the amorphous polyester resin, is from 0.010 to 0.040 in an absorption spectrum obtained by an ATR method (total reflectance method) using a Fourier transform infrared (FT-IR) spectrophotometer.

Image forming apparatus, toner, and process cartridge

A toner is provided that comprises a colorant and a binder resin, wherein the binder resin comprises a polyester resin that is prepared by a polycondensation reaction in the presence of at least a titanium-containing catalyst expressed by General Formula (II) or (II), the toner has a volume average particle diameter of 2.0 &#x3bc;m to 10.0 &#x3bc;m and a ratio Dv/Dn within a range of 1.00 to 1.40, in which Dv represents a volume average particle diameter and Dn represents a number average particle diameter,Ti(&#x2014;X)m(&#x2014;OH)n&#x2003;&#x2003;General Formula (I)O&#x2550;Ti(&#x2014;X)p(&#x2014;OR)q&#x2003;&#x2003;General Formula (II) in General Formulas (I) and (II), X represents a residue of a mono-alkanolamine of 2 to 12 carbon atoms or a polyalkanolamine from which a hydrogen atom of one hydroxyl group is removed; other hydroxyl group(s) and still other hydroxyl group(s), within the polyalkanolamine molecule that has a directly bonding Ti atom, may polycondense to form a ring structure; other hydroxyl group(s) and still other hydroxyl group(s) may polycondense intermolecularly to form a repeating structure; and the polymerization degree is 2 to 5 in a case of forming the repeating structure; R represents one of a hydrogen atom and alkyl groups of 1 to 8 carbon atoms that may have 1 to 3 ether bonds; 'm' is an integer of 1 to 4; 'n' is an integer of 0 to 3; the sum of &#x201c;m&#x201d; and &#x201c;n&#x201d; is 4; &#x201c;p&#x201d; is an integer of 1 or 2; &#x201c;q&#x201d; is an integer of 0 or 1; the sum of &#x201c;p&#x201d; and &#x201c;q&#x201d; is 2; and in a case that &#x201c;m&#x201d; and &#x201c;p&#x201d; is 2 or more, the respective Xs may be identical or different each other.

Growing community of inventors

Mishima, Japan

Hyo Shu