Having Specified Toner Particle Size Distribution Patents (Class 430/110.4)
  • Patent number: 7939232
    Abstract: A toner or two-component developer is obtained by mixing, aggregating, and heating resin particles, colorant particles, and wax particles in an aqueous medium. A gel permeation chromatography (GPC) measurement of the resin particles shows that a weight-average molecular weight is 10000 to 60000, and the ratio of the weight-average molecular weight to a number-average molecular weight is 1.5 to 6. The wax particles include at least a first wax and a second wax. An endothermic peak temperature (melting point Tmw1 (° C.)) of the first wax based on a DSC method is 50° C. to 90° C. An endothermic peak temperature (melting point Tmw2 (° C.)) of the second wax based on the DSC method is at least 5° C. to 50° C. higher than Tmw1. Thus, the toner can have a smaller particle size and a sharp particle size distribution without requiring a classification process, can achieve a longer life, and can suppress transfer voids or scattering during transfer.
    Type: Grant
    Filed: November 1, 2005
    Date of Patent: May 10, 2011
    Assignee: Panasonic Corporation
    Inventors: Yasuhito Yuasa, Hidekazu Arase, Masahisa Maeda
  • Patent number: 7935468
    Abstract: There is provided a toner which is excellent in temporal stability and environmental stability of charges and which is capable of forming images that contains almost no background fog and has high density even in a long-term use and in use at a high-temperature and high-humid circumstance, and furthermore the toner which is not scattered inside an image forming apparatus and thus causes no contamination inside the apparatus, and there is further provided a method of manufacturing the above toner. An organic boron compound is contained as a charge control agent, a surface CCA concentration per specific surface area of toner falls in a range from 2.1×10?6 g/cm2 to 5.5×10?6 g/cm2, and a surface CCA concentration is 1.8×10?3 g/g or more.
    Type: Grant
    Filed: June 18, 2007
    Date of Patent: May 3, 2011
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yoshinori Yamamoto, Satoshi Ogawa, Masao Suzuki, Yoshiaki Akazawa
  • Patent number: 7925190
    Abstract: The invention provides a developer supply device, a developer container, a developer and an image forming apparatus such that the developer is discharged stably from the developer container with a stable toner concentration in the developer, without damaging the developer, and in a relatively simple and small-size device having a relatively high degree of freedom as regards layout. The developer supply device comprises a partially or wholly deformable developer container and a pump for suctioning the developer held in the developer container, together with a gas, and for discharging the developer towards a developing unit. The toner comprises an additive formed so as to have a volume average particle size of 50 to 500 nm. The carrier is formed so as to have a weight average particle size of 20 to 60 ?m. The developer is formed so that the carrier concentration thereof is 1 to 30 wt %.
    Type: Grant
    Filed: May 31, 2007
    Date of Patent: April 12, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Keiko Matsumoto, Mugijirou Uno, Hiroyuki Okaji
  • Publication number: 20110065033
    Abstract: A toner including a binder resin, a coloring agent, a releasing agent, and an additive, the releasing agent having a loss on heat of from 0.5 to 2.0% after being left at 165° C. for 10 minutes, the ratio (P2850/P828) of an absorption strength of a peak at 2,850 cm?1 ascribed to the releasing agent to an absorption strength of a peak at 828 cm31 1 ascribed to the binder resin ranging from 0.03 to 0.25 wherein the ratio is measured according to Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR), and an amount of heat of melting ascribable to the releasing agent according to differential scanning calorimetry (DSC) ranging from 2 to 25 mj/mg.
    Type: Application
    Filed: September 14, 2010
    Publication date: March 17, 2011
    Inventors: Osamu UCHINOKURA, Fumihiro Sasaki, Satoshi Kojima, Daisuke Inoue
  • Patent number: 7906264
    Abstract: The invention provides: an electrostatic latent image developing toner comprising a non-crystalline resin, a crystalline resin having a melting point of 50 to 100° C., and a colorant, and satisfying the relationship represented by the following formula (1), wherein A represents the content of the crystalline resin (% by mass) in the entire toner, and B represents the content of the crystalline resin (% by mass) in a classified toner which has been prepared by classifying the toner such that the volume average particle diameter thereof is in the range of (?)×D50T to (?)×D50T, wherein D50T represents the volume average particle diameter of the entire toner, and a method for producing the same, as well as an electrostatic latent image developing developer, a toner cartridge, a process cartridge, and an image forming apparatus using the same.
    Type: Grant
    Filed: February 12, 2007
    Date of Patent: March 15, 2011
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Masaru Takahashi, Hirokazu Hamano, Atsushi Sugawara, Masaki Nakamura, Yasuhiro Oya
  • Publication number: 20110027715
    Abstract: A developer for forming an image on a transfer medium includes a toner having a volume average particle size of 3 to 8 ?m, and a mixed carrier including a first carrier having a volume average particle size of 25 to 40 ?m and conductivity that corresponds to a current value of 1.5 to 2.0 ?A at application of 1000 V for 30 sec, and a second carrier having a volume average particle size of 35 to 60 ?m larger than the first carrier and conductivity that corresponds to a current value of 2.0 to 4.0 ?A larger than the first carrier at application of 1000 V for 30 sec.
    Type: Application
    Filed: July 29, 2010
    Publication date: February 3, 2011
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventor: Mitsutoshi Watanabe
  • Publication number: 20110020745
    Abstract: The present invention relates to, in the toner including toner particles having a biding agent resin, colorings and a release agent, an electrostatic image developing toner, its composition, and a preparation method thereof. The electrostatic image developing toner is prepared by the method comprising: (1) preparing an inorganic dispersion medium; (2) dispersing/dissolving a polymerizable monomer mixture; (3) micronizing the liquid obtained in step (2) in the liquid obtained in step (1) with high shear force in order to create droplets; (4) performing radical polymerization of the micronized droplets obtained in step (3); (5) aggregating particles obtained in step (4); (6) fusing the aggregate obtained in step (5); (7) cleaning and drying the toner obtained by step (6); and (8) adding additives to impart electrification and fluidity to a toner obtained by step (7).
    Type: Application
    Filed: March 12, 2009
    Publication date: January 27, 2011
    Inventors: Jae-Goang Yu, Ho-Geun Jo
  • Publication number: 20110003244
    Abstract: The toner includes a binder resin; a colorant; and a release agent. The first inter-particle force Fp(A) of the toner, which is measured under an environmental condition of 23° C. and 60% RH after the toner is pressed for 1 minute at 25° C. under a compression stress of 15 kg/cm2, is from 1.0×10?9 (N) to 1.0×10?6 (N). The difference (Fp(B)?Fp(A)) between the second inter-particle force Fp(B) of the toner, which is measured under the environmental condition of 23° C. and 60% RH after the toner is pressed for 1 minute at 50° C. under a compression stress of 15 kg/cm2, and the first inter-particle force Fp(A) is 0 (N) to 1.0×10?7 (N).
    Type: Application
    Filed: June 23, 2010
    Publication date: January 6, 2011
    Inventors: Daisuke INOUE, Fumihiro Sasaki, Osamu Uchinokura, Satoshi Kojima, Hideki Sugiura, Naoko Morisawa
  • Patent number: 7862974
    Abstract: An embodiment may be an electrophotographic toner which comprises at least one toner particle which comprises an inner layer and an outer layer covering the inner layer, wherein a cross-sectional area ratio of the outer layer to the inner layer is 0.05-0.46, and wherein a non-uniform thickness exists in the outer layer, and further the average thickness (t) taken at 5 positions as calculated by, is about 0.2—about 1.0 ?m, t=(t1+t2+t3+t4+t5)/5 (unit of t1-t5 is ?m) wherein t1 represents a thickness of the thickest part of the outer layer, and t2-t5 each represent a thickness of a second to a fifth thickest part of the outer layer in one particle, and wherein a glass transition point Tg of the inner layer is about 2—about 45° C. lower than Tg of the outer layer.
    Type: Grant
    Filed: October 13, 2009
    Date of Patent: January 4, 2011
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventors: Kouji Sugama, Masafumi Uchida, Kenji Yamane, Kenji Hayashi, Ryuji Kitani
  • Patent number: 7862971
    Abstract: An emulsion aggregation toner having toner particles comprising a gel latex, a high Tg latex and at least one wax, wherein the toner fuses at about 170° C. to about 220° C. at process speeds of from about 560 mm/s to about 870 mm/s, wherein the toner exhibits a crease fix property of less than about 60 and a half-toner rub fix property of less than about 0.15. The toner exhibits excellent half-tone rub fix performance and crease fix at high print speeds.
    Type: Grant
    Filed: January 31, 2007
    Date of Patent: January 4, 2011
    Assignee: Xerox Corporation
    Inventors: Karen A. Moffat, Edward G. Zwartz, T. Brian McAneney, Fernando P. Yulo
  • Publication number: 20100285402
    Abstract: A toner is provided which includes a first binder resin, a second binder resin that is a reaction product of a compound having an active hydrogen group with a polymer reactive with the active hydrogen group, a colorant, and a release agent. The toner includes the second binder resin in an amount of from 6.4 to 40.9% by weight, and the reaction product includes organic-solvent-insoluble components in an amount of from 20 to 95% by weight. A method of manufacturing the toner is also provided.
    Type: Application
    Filed: May 10, 2010
    Publication date: November 11, 2010
    Inventors: Akinori Saitoh, Masahide Yamada, Hiroshl Yamada
  • Publication number: 20100273103
    Abstract: The present invention provides an image of high image quality by using a magnetic carrier coated with a novel coating resin composition. Further, the present invention stably provides a good image which is hardly influenced by environmental fluctuation and long-term use and has a superior stability of a charging amount when left to stand especially under high temperature and high humidity environments. The present invention also provides a magnetic carrier characterized in that a carrier core surface is coated with a copolymer containing at least, as copolymerization components, an acrylic monomer having a specific structure and an acrylic macromonomer having a specific structure.
    Type: Application
    Filed: February 26, 2009
    Publication date: October 28, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yoshinobu Baba, Koh Ishigami, Naoki Okamoto, Tomoko Endo
  • Patent number: 7820351
    Abstract: An image forming apparatus for forming images with a toner and includes an image forming section, a paper feeding section and an image reading section, in which the non-magnetic toner is as follows: the particle size D10V and the particle size D90V of the toner satisfy the following formula (1), the particle size D50V is from 5 to 8 ?m, and the content of the toner particles having a particle size of at most 5 ?m is from 15 to 35% by number: 0.415?(D10V?D90V)/D10V?0.475??(1) wherein D10V, D50V and D90V each are a particle size where a cumulative volume from the large particle size side in the cumulative volume distribution of the toner particles reaches 10%, 50% and 90%, respectively.
    Type: Grant
    Filed: December 27, 2006
    Date of Patent: October 26, 2010
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masao Suzuki, Yoshiaki Akazawa, Hiroshi Onda, Satoshi Ogawa, Yoshinori Yamamoto
  • Publication number: 20100261110
    Abstract: A toner, has a number mode diameter of 3 ?m or more and 6 ?m or lower and a particle size distribution of a toner including an externally-applied agent in the range of 0.6 ?m to 400 ?m in which the number frequency of a toner smaller than the number mode diameter is smaller than the number frequency of a toner equal to or larger than the number mode diameter.
    Type: Application
    Filed: April 12, 2010
    Publication date: October 14, 2010
    Applicant: Seiko Epson Corporation
    Inventors: Soichi YAMAZAKI, Takatomo FUKUMOTO, Hideki OKADA, Toshikazu ONO
  • Publication number: 20100261111
    Abstract: A toner includes at least a binder resin, a colorant, and a release agent. The toner contains base toner particles having an average volume particle size of 2 ?m to 6 ?m, small particle silica having an average volume particle size of 7 nm to 15 nm, large particle silica having an average volume particle size of 50 nm to 400 nm, small particle transition alumina having an average volume particle size of 7 nm to 20 nm, and large particle ?-type alumina having an average volume particle size of 50 nm to 400 nm or large particle cerium oxide having an average volume particle size of 50 nm to 400 nm.
    Type: Application
    Filed: April 13, 2010
    Publication date: October 14, 2010
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Tomohiro ARUGA, Hideki OKADA, Yoichi YAMADA, Daisuke MATSUMOTO
  • Patent number: 7811738
    Abstract: In an image forming method including a charging step, an exposure step, a development step using a developing roll, a transfer step, a fixing step and a cleaning step of removing a toner remaining on the surface of a photosensitive member after the transfer step, the developing roll has a surface brightness of 30 to 220 and a surface roughness Rz of 1 to 20 ?m, the cleaning blade is a cleaning blade made of a polyurethane elastomer and having a peak value of at most 0.95, a peak temperature of ?15 to 10° C. and a width at half maximum of at least 25° C. in viscoelasticity tan ?, the toner has a volume average particle diameter of 4 to 10 ?m and an average circularity from 0.950 to 0.995, the charge level of the toner on the surface of the photosensitive member is 10 to 80 ?C/g in terms of an absolute value, and the pH of a water extract of the toner is 3 to 8.
    Type: Grant
    Filed: May 31, 2005
    Date of Patent: October 12, 2010
    Assignees: Zeon Corporation, Toyo Tire & Rubber Co., Ltd., Yamanashi Electronics Co., Ltd., Shin-Etsu Polymer Co., Ltd.
    Inventors: Kazunori Shigemori, Muneharu Ito, Toshiyuki Nagai, Toshiro Murano, Fuminori Tsuruta, Tomoharu Takeuchi, Masahiro Ikeda, Sokuei Motoda
  • Publication number: 20100233609
    Abstract: The present invention relates to toner compositions containing: toner particles made of: binder resin; colorant; and a wax which is dispersed in the toner particles, where the toner composition satisfies relationship (2): B?394?400A? when 0.950<A??0.965 (2) where A? represents an average circularity of the toner composition, B represents a content of toner particles having a particle diameter not greater than 3 ?m expressed in % by number, and a concentration of the wax at a surface of the toner particles is larger than a concentration thereof in the center of the toner particles.
    Type: Application
    Filed: April 7, 2010
    Publication date: September 16, 2010
    Inventors: Hiroto HIGUCHI, Fumihiro Sasaki, Shinichiro Yagi, Shigeru Emoto, Junichi Awamura, Naohito Shimota, Masami Tomita, Toshiki Nanya, Takahiro Honda, Maiko Kondo
  • Publication number: 20100233607
    Abstract: A toner for developing electrostatic images which is obtained by melt mixing at least a binder resin and a coloring agent, forming a powder material by pulverizing the obtained mixture after cooling and removing rough particles and fine particles from the formed powder material by classification, wherein inorganic fine particles having a roundness of 1.00 to 1.30, an average of the diameter of primary particles of 0.05 to 0.45 ?m and a ratio of a standard deviation to the average of the diameter of primary particles of 0.25 or smaller are added as an external additive, and a process for producing a toner for developing electrostatic images which comprises melt mixing at least a binder resin and a coloring agent, forming a powder material by pulverizing the obtained mixture after cooling, rounding the powder material by a heat treatment and adding the above inorganic fine particles to the rounded powder material.
    Type: Application
    Filed: January 25, 2007
    Publication date: September 16, 2010
    Applicant: IMEX CO., LTD.
    Inventors: Shigetoshi Asano, Shuzo Nakayama, Masashi Ueda, Katsutoshi Saito, Kazuma Okamura
  • Publication number: 20100227267
    Abstract: A method for producing a toner, containing: ultrasonically vibrating a liquid toner composition in which a toner material containing at least a binder resin and a colorant is dissolved or dispersed in a solvent; introducing the liquid toner composition to a liquid chamber, and ejecting the liquid toner composition as droplets from an ejecting plate having a plurality of holes and disposed on one surface of the liquid chamber; and drying and solidifying the droplets so as to produce a toner, wherein the ultrasonically vibrating is performed before the introducing the liquid toner composition to the liquid chamber.
    Type: Application
    Filed: March 5, 2010
    Publication date: September 9, 2010
    Inventors: Yasutada SHITARA, Yoshihiro Norikane, Yohichiroh Watanabe, Andrew Mwaniki Mulwa
  • Patent number: 7771910
    Abstract: An image forming method is disclosed, comprising (a) forming a toner image on an image forming body, (b) transporting the image forming body to a transfer region, (c) overlapping an image supporting body onto the image forming body, (d) radiating ultrasonic waves onto the image forming body and the image supporting body by an ultrasonic radiation means with applying an electric field between the image forming body and the image supporting body to transfer the toner image onto the image supporting body and (e) subjecting the toner image on the image supporting body to contact heat-fixing to fix the toner image, wherein a toner is comprised of toner particles containing a resin, a colorant and a releasing agent, and the toner particles exhibiting a coefficient of variation of shape factor of not more than 16% and a coefficient of variation of number particle size distribution of not more than 27%.
    Type: Grant
    Filed: August 23, 2004
    Date of Patent: August 10, 2010
    Assignee: Konica Minolta Holdings, Inc.
    Inventors: Hiroshi Yamazaki, Hiroyuki Yamada, Tomoe Kitani
  • Patent number: 7769311
    Abstract: An image forming apparatus and an image forming method are provided which form high-quality fixed images having no fogs and the like defects, in which apparatus and method a toner entering a pressure-contact area between rollers is prevented from scattering. A control is performed on preheating conditions for preheating an unfixed toner image on a recording medium, which unfixed toner image indicates a toner image transferred but not yet fixed, and a control is further performed such that an amount of toner attached to the recording medium at a coverage rate of 100% is 0.4 mg/cm2 or less, with the result that the toner is prevented from scattering when the recording medium carrying the unfixed toner image passes through a pressure-contact area formed between a heating roller and a pressurizing roller in a fixing step.
    Type: Grant
    Filed: May 22, 2008
    Date of Patent: August 3, 2010
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Yoritaka Tsubaki
  • Publication number: 20100189464
    Abstract: A developer includes a toner including a toner mother particle having a resin and a colorant and an external additive to be added to a surface of the toner mother particle. The toner has a volume average particle size of greater than or equal to 3.0 ?m and smaller than or equal to 7.0 ?m and has a surface roughness Rzjis of greater than or equal to 75.3 nm and smaller than or equal to 236.9 nm under observation using a scanning probe microscope. The external additive is titanium oxide having a particle size of greater than or equal to 10 nm and smaller than or equal to 100 nm.
    Type: Application
    Filed: January 21, 2010
    Publication date: July 29, 2010
    Applicant: OKI DATA CORPORATION
    Inventor: Yuki MATSUURA
  • Publication number: 20100178605
    Abstract: A toner to develop an electrostatic latent image which includes a latex, a colorant, and a release agent, wherein the toner has a complex viscosity (?*) in a range of about 2.5×102 to about 1.0×103 Pa·s and a loss tangent (tan ?) in a range of about 1.3 to about 2.3 at a temperature of about 160° C. and wherein the ?* is defined by a formula ?*=(G?2+G?2)1/2/w, and the tan ? is defined by a formula G?/G?, where G? is a storage elastic modulus and G? is a loss elastic modulus as determined under the following conditions of an angular velocity being about 6.28 rad/s and at a temperature increasing at a rate of about 2.0° C/min.
    Type: Application
    Filed: December 29, 2009
    Publication date: July 15, 2010
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Tae-hoe KOO, Min-young Cheong, Jun-young Lee, Jae-hwan Kim, Yo-da Shin
  • Publication number: 20100178604
    Abstract: An electrophotographic toner includes a latex, a colorant, and a release agent, wherein G?(80) is in a range of about 2.0×105 Pa to about 3.0×106 Pa and G?(80)/G?(140) is in a range of about 2.0×102 to about 3.0×103, wherein in regard to a molecular weight distribution on a gel permeation chromatography (GPC) chromatogram, the molecular weight region of 1.0×104 g/mol or less of a tetrahydrofuran (THF)-soluble component of the electrophotographic toner is about 5% or less, and the molecular weight region of 1.0×105 g/mol or more of the THF-soluble component of the electrophotographic toner is in a range of about 5% to about 20%, where G?(80) and G?(140) respectively denote storage moduli of the electrophotographic toner at temperatures of 80° C. and 140° C. when a dynamic viscoelasticity according to a sine-wave vibration is measured at an angular velocity of 6.28 rad/sec and at a temperature increase rate of 2.0° C./min.
    Type: Application
    Filed: November 25, 2009
    Publication date: July 15, 2010
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Jeong-hyun LEE, Yong-kyun Jung, Kyeong Pang
  • Patent number: 7745084
    Abstract: A toner including a binder resin and a colorant, wherein a pellet of the toner which is prepared by applying a pressure of 15 kg/cm2 to the toner has a tensile strength of from 900 Pa to 10,000 Pa, and wherein the toner has a methanol wettability of from 25 to 65% by volume, wherein the methanol wettability is measured by a method in which the toner is dispersed in a mixture solvent of water and methanol, and methanol is added to the toner dispersion while checking the transparency of the dispersion to determine a transparency fall starting point, wherein the methanol wettability is defined as {Vm/(Vm+Vw)}×100, wherein Vm represents a total volume (ml) of methanol in the dispersion at the transparency dropping point, and Vw represents the total volume of the pure water added.
    Type: Grant
    Filed: July 21, 2005
    Date of Patent: June 29, 2010
    Assignee: Ricoh Company Limited
    Inventors: Hideki Sugiura, Hitoshi Iwatsuki
  • Publication number: 20100159379
    Abstract: Disclosed are a toner for developing an electrostatic latent image and a method of preparing the same. The toner may include latex, a pigment and a releasing agent. The lowest crossover temperature of the toner at which the storage modulus (G?) and the loss modulus (G?) of the toner are substantially equal to each other may be in the range of about 65 to about 80° C. The weight average molecular weight (Mw) of the toner may be in the range of about 65,000 to about 75,000. The z-average molecular weight (Mz) of the toner may be in the range of about 110,000 to about 220,000.
    Type: Application
    Filed: December 7, 2009
    Publication date: June 24, 2010
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Jun-Young LEE, Min-Young Cheong, Jae-Hwan Kim, Yo-Da Shin, Tae-Hoe Koo
  • Publication number: 20100151378
    Abstract: Disclosed is toner in which is used in an image formation process comprising the steps of transferring an image of toner formed on a photoreceptor onto a recording sheet, and removing any residual toner remaining on any of the photoreceptor, an intermediate transfer member and a secondary transfer member with a cleaning blade, the toner containing at least toner particles (A) and small particles (B), wherein the toner particles (A) have an average circularity of from 0.93 to 0.99 and a number-based median diameter (D50) of from 3.0 to 8.0 ?m, the small particles (B) have an average circularity of from 0.70 to 0.92 and a number-based median diameter (D50) of from 0.15 to 0.60 times that of the toner particles (A), and the surface energy of the toner particles (A) is different from that of the small particles (B).
    Type: Application
    Filed: December 7, 2009
    Publication date: June 17, 2010
    Applicant: KONICA MINOLTA BUSINESS TECHNOLOGIES, INC.
    Inventors: Hiroyuki KOZURU, Yoshiyasu MATSUMOTO, Kosuke NAKAMURA, Futoshi KADONOME, Takanari KAYAMORI
  • Patent number: 7736826
    Abstract: A toner composition including toner particles including at least a binder resin; and a colorant, wherein the toner composition satisfies at least one of the following relationships (1) and (2): B?14 when 155<A?180; and B?0.6A?79 when 145?A?155,??(1) wherein A represents a shape factor SF-1 of the toner composition and B represents a content of toner particles having a particle diameter not greater than 3 ?m; and B?14 when 0.920?A??0.950; and B?394?400A? when 0.950<A??0.965??(2) wherein A? represents an average circularity of the toner composition and B represents a content of toner particles having a particle diameter not greater than 3 ?m.
    Type: Grant
    Filed: September 17, 2008
    Date of Patent: June 15, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroto Higuchi, Fumihiro Sasaki, Shinichiro Yagi, Shigeru Emoto, Junichi Awamura, Naohito Shimota, Masami Tomita, Toshiki Nanya, Takahiro Honda, Maiko Kondo
  • Patent number: 7727699
    Abstract: The present invention relates to a process for producing a toner for electrophotography, including: (a) a step of aggregating resin particles containing a resin binder in an aqueous medium; and (b) a step of unifying the aggregated resin particles, the step (a) including: (a-1) a step of adding a monovalent salt as an aggregating agent; and (a-2) a step of adding at least one compound selected from the group consisting of alkylethersulfates represented by the formula (1): R—O—(CH2CH2O)nSO3M??(1) wherein R is an alkyl group; n represents an average molar number of addition and is a number of more than 0 and not more than 15 (0<n?15), and M is a monovalent cation, alkylsulfates and linear alkylbenzenesulfonates. The toner of the present invention has a small particle size which is controlled with a high accuracy, and a sharp particle size distribution, and a particle shape of the toner is readily controlled even at a low temperature, and further the obtained toner exhibits a high circularity.
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: June 1, 2010
    Assignee: Kao Corporation
    Inventors: Nobumichi Kamiyoshi, Manabu Suzuki, Yutaka Murai
  • Publication number: 20100119255
    Abstract: An image forming apparatus including an image bearer; a charging device charging the image bearer; a light irradiating device irradiating the charged image bearer with light to form an electrostatic image; a developing device developing the electrostatic image with a developer including a toner to form a toner image on the image bearer; a transfer device transferring the toner image; and a cleaning device cleaning the image bearer, wherein the volume average particle diameter of the toner is greater than 5.0 ?m and less than 5.5 ?m, the content of toner particles having a particle diameter of not greater than 4.0 ?m is not higher than 20% by number, the ratio of the first shape factor SF-1 to the second shape factor SF-2 is from 1.00 to 1.15, and the content of toner particles having a SF-2 of not less than 115 is not less than 67.
    Type: Application
    Filed: January 19, 2010
    Publication date: May 13, 2010
    Inventors: Takuya SESHITA, Toyoshi SAWADA, Tomomi SUZUKI, Tsuneyasu NAGATOMO, Satoshi KOJIMA
  • Patent number: 7695878
    Abstract: An image forming apparatus including an image bearer; a charging device charging the image bearer; a light irradiating device irradiating the charged image bearer with light to form an electrostatic image; a developing device developing the electrostatic image with a developer including a toner to form a toner image on the image bearer; a transfer device transferring the toner image; and a cleaning device cleaning the image bearer, wherein the volume average particle diameter of the toner is greater than 5.0 ?m and less than 5.5 ?m, the content of toner particles having a particle diameter of not greater than 4.0 ?m is not higher than 20% by number, the ratio of the first shape factor SF-1 to the second shape factor SF-2 is from 1.00 to 1.15, and the content of toner particles having a SF-2 of not less than 115 is not less than 67.8% by number.
    Type: Grant
    Filed: March 16, 2007
    Date of Patent: April 13, 2010
    Assignee: Ricoh Company Limited
    Inventors: Takuya Seshita, Toyoshi Sawada, Tomomi Suzuki, Tsuneyasu Nagatomo, Satoshi Kojima
  • Patent number: 7687214
    Abstract: A two-component developer and an image formation method for two-component development type are provided. With this developer and this method, even if toners have a small grain diameter and a high density of pigments for economizing the toner consumption, cracking and toner spent caused by the stress from carriers are suppressed, so that less deteriorated and stabler images can be obtained throughout a long time period. The two-component developer includes toner particles containing at least a binding resin and a pigment. A mean volume particle diameter of the toner particles is between 5.5 ?m and 7 ?m. A number percent of the toner particles with a mean volume particle diameter of 5 ?m or below, and a volume percent of the toner particles with a mean volume particle diameter between 8 ?m and 12.7 ?m, with respect to the total toner particles, respectively, are set to be within a predetermined range. Density of the pigment in the toner particles is between 8 weight percent and 20 weight percent.
    Type: Grant
    Filed: October 19, 2005
    Date of Patent: March 30, 2010
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yasuhiro Shibai, Yoritaka Tsubaki, Keiichi Kikawa
  • Publication number: 20100075245
    Abstract: Disclosed is a resin particle having a volume average particle diameter of 10 nm to 500 nm, obtained by polymerizing an addition polymerizable monomer containing a silsesquioxane (a) represented by Formula (I) or by copolymerizing the silsesquioxane (a) with an addition polymerizable monomer (b), where R1 to R7 each independently represent a group selected from the group consisting of hydrogen, alkyl having 1 to 40 carbon atoms, substituted or unsubstituted aryl, and substituted or unsubstituted arylalkyl; any hydrogen in the alkyl group is optionally substituted by fluorine and any —CH2— is optionally substituted by —O—, —CH?CH—, cycloalkylene or cycloalkenylene; any hydrogen in alkylene in the arylalkyl group is optionally substituted by fluorine and any —CH2— is optionally substituted by —O— or —CH?CH—; and A1 represents an addition polymerizable functional group.
    Type: Application
    Filed: September 22, 2009
    Publication date: March 25, 2010
    Inventors: Masaki Watanabe, Naohito Shimota, Hiroshi Yamashita, Naohiro Watanabe, Tsuneyasu Nagatomo, Tsuyoshi Sugimoto, Shinichi Wakamatsu, Kenya Itoh, Mikio Yamahiro
  • Patent number: 7666565
    Abstract: A method of forming electrophotographic toner. An organic solution containing a polymer resin and a solvent and an aqueous solution containing an anti-coagulant are provided. The aqueous solution is added into the organic solution to form colloidal polymer particles. The colloidal polymer particles are then aggregated, coalesced, and solidified to form toner particles.
    Type: Grant
    Filed: August 26, 2005
    Date of Patent: February 23, 2010
    Assignee: Sinonar Corp.
    Inventors: Ming-Huei Liu, Chih-Chia Hung, Fang-Yi Hsu
  • Publication number: 20100003613
    Abstract: 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.
    Type: Application
    Filed: July 6, 2009
    Publication date: January 7, 2010
    Inventors: Takahiro Honda, Yohichiroh Watanabe, Yoshihiro Norikane, Shinji Ohtani
  • Patent number: 7625685
    Abstract: The present invention provides a magnetic mono-component toner which can suppress a selection development on a latent image carrier and can maintain favorable image properties for a long period by using a toner having the coarse powder distribution (S) within a given range in a jumping developing method and an image forming method which uses the toner. In the toner used in the jumping developing method which develops an electrostatic latent image formed on a latent image carrier using a developer carrier, the toner includes toner particles which contain at least a binding resin and a magnetic powder, and the coarse powder distribution (S) of the toner particles satisfies a following formula (1). Coarse powder distribution (S)=(50?A)/2?17 (volume %/?m)??(1) (wherein, A is a volume % of the coarse powder having particle sizes larger than D50 based on volume by 2 ?m or more).
    Type: Grant
    Filed: October 9, 2008
    Date of Patent: December 1, 2009
    Assignee: Kyocera Mita Corporation
    Inventor: Hideaki Kawata
  • Publication number: 20090291384
    Abstract: A method of manufacturing a toner including a first dispersing wherein (i) at least two binder resins having different weight average molecular weight, (ii) a coloring agent and (iii) a releasing agent are dispersed in an organic solvent to obtain an oil phase, a second dispersing comprising continuously mixing the oil phase with an aqueous medium comprising a solid particulate dispersion agent to form a dispersion emulsion comprising emulsification particles (where at least one of the first and the second dispersing is carried out under at least one condition based on a property of the binder resin which has the lowest weight-average molecular weight), measuring automatically the volume average particle diameter of the dispersion emulsion during the second dispersing, calculating automatically a difference between the volume average particle diameter of the dispersion emulsion measured during the measuring and a target volume average particle diameter, maintaining automatically an allowable difference betwee
    Type: Application
    Filed: May 20, 2009
    Publication date: November 26, 2009
    Inventor: Hiroshi TAKAHASHI
  • Publication number: 20090291274
    Abstract: The use of electrographic printing to prepare prints which have a desired tactile feel or raised information in a controlled manner by utilizing a developer having toner particle size larger than 50 microns volume average diameter and carrier particles larger than the toner particle size such that the volume average distribution overlap between the toner distribution curve and carrier particle distribution curve is less than 35% and the carrier and toner particles have a volume average diameter size differential equal to or greater than 5 microns or the ratio of carrier-to-toner volume average diameter exceeds 1.25.
    Type: Application
    Filed: May 21, 2008
    Publication date: November 26, 2009
    Inventors: Dinesh Tyagi, Patrick M. Lambert, Mark C. Zaretsky, Thomas N. Tombs
  • Publication number: 20090291379
    Abstract: To provide toner which is capable of suppressing consuming amount of toner and preventing cleaning failure, and even when a high speed printing machine is used, can reduce a problem of e.g. fogging in a long-term use and is excellent in image stability. A toner for developing an electrostatic charge image, which comprises toner matrix particles formed in an aqueous medium, wherein the toner has a volume median diameter (Dv50) of from 4.0 ?m to 7.0 ?m; and the relationship between the volume median diameter (Dv50) and the percentage in number (Dns) of toner particles having a particle diameter of from 2.00 ?m to 3.56 ?m satisfies the following formula (1): Dns?0.233EXP(17.3/Dv50)??(1) where Dv50 is the volume median diameter (?m) of the toner, and Dns is the percentage in number of toner particles having a particle diameter of from 2.00 ?m to 3.56 ?m.
    Type: Application
    Filed: March 30, 2007
    Publication date: November 26, 2009
    Applicant: MITSUBISHI CHEMICAL CORPORATION
    Inventors: Masaya Oota, Shiho Sano, Takeshi Oowada, Masakazu Sugihara, Teruki Senokuti, Shiro Yasutomi, Yumi Hirabaru
  • Patent number: 7608374
    Abstract: A toner including a binder resin, and a release agent, wherein the following relationships are satisfied: 2 ?m?D4?4 ?m??(a) 0.05 ?m?Dw?0.3 ?m??(b) Dw?0.075×D4??(c) F??40×Dw+19??(d) F?20×Dw+5??(e) wherein D4 is a weight-average particle diameter of the toner, Dw is an average dispersion diameter of the release agent and F is a pulverizability index of the toner.
    Type: Grant
    Filed: January 12, 2007
    Date of Patent: October 27, 2009
    Assignee: Ricoh Company, Ltd.
    Inventor: Masami Tomita
  • Patent number: 7598013
    Abstract: A toner comprising: (i) toner particles, each toner particle comprising a binder resin and a colorant; and (ii) an oxymonocarboxylic acid or a salt thereof, wherein a total content of the oxymonocarboxylic acid or the salt thereof in the toner is 10 to 173 ppm based on the total weight of the toner.
    Type: Grant
    Filed: January 19, 2007
    Date of Patent: October 6, 2009
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventors: Eiichi Yoshida, Masahiko Nakamura, Kaori Soeda, Tomoko Mine, Kenichi Onaka
  • Publication number: 20090246672
    Abstract: A toner for the development of an electrostatic image is provided wherein at least one layer of a particulate resin is coated onto a substantial portion of the surface of an agglomerate of particles made from at least primary polymer particles and primary colorant particles, wherein at least one of the primary polymer particles and the particulate resin contains a wax, and the particulate resin of the outermost layer is substantially free of wax and a process for producing the toner.
    Type: Application
    Filed: April 24, 2008
    Publication date: October 1, 2009
    Applicant: MITSUBISHI CHEMICAL CORPORATION
    Inventors: Tomoko Ishikawa, Yuqing Xu, Katsuo Koizumi, Noriaki Takahashi, Osamu Ando
  • Publication number: 20090246670
    Abstract: Carrier particles for forming a wiring circuit pattern by an electrophotographic developing method which are used for directly forming a circuit shape on an insulating layer, with any of a metal powder, an inorganic compound powder, or a mixed raw material powder thereof used as a toner powder for forming a circuit, the toner powder for forming a circuit being adhered to a surface of the carrier particles by electrostatic force and then transported to a surface of the insulating layer, wherein the carrier particles include a resin coated layer of an acrylic resin composition containing an amino-group-containing polymer on the surface of the carrier core material particles, the coating amount of the acrylic resin composition is 0.3 to 3.0% by weight based on a carrier core material weight of 100% by weight, and a shape factor SF-1 of the carrier core material particles is 100 to 110.
    Type: Application
    Filed: March 6, 2009
    Publication date: October 1, 2009
    Applicant: POWDERTECH CO., LTD.
    Inventors: Koji AGA, Atsushi NII
  • Patent number: 7593671
    Abstract: A developing device includes a developer bearing member, a developer supplying conveyer, a developer receiving conveyer and a developer agitating conveyer. The developer supplying conveyer or the developer receiving conveyer has at least one dividing position. The dividing position is a position at which the conveying direction of the developer reverses, and a position which is arranged so that if the dividing position is projected to the developer bearing member along a plane which is perpendicular to the widthwise direction of the developer bearing member, the projected position on the developer bearing member is within an area in which the developer is borne on the developer bearing member.
    Type: Grant
    Filed: December 5, 2006
    Date of Patent: September 22, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Emiko Ishikawa, Chiemi Kaneko, Hirokatsu Suzuki, Kenichi Taguma
  • Publication number: 20090226836
    Abstract: A method of manufacturing a toner including granulating mother toner particles in an aqueous medium to obtain a slurry containing the mother toner particles and adjusting a size distribution of the mother toner particles by screening coarse mother toner particles from the slurry with a screen to obtain the toner containing mother toner particulates.
    Type: Application
    Filed: March 6, 2009
    Publication date: September 10, 2009
    Inventors: OSAMU UCHINOKURA, AKINORI SAITOH, JUNICHI AWAMURA, MASAHIDE YAMADA, HIROSHI YAMADA
  • Publication number: 20090226837
    Abstract: A method of manufacturing a toner includes preparing a droplet forming device, comprising a storage portion to store a toner composition solution, a thin film formed from a rigid material, bonded to the storage portion by a bonding material, and provided with a nozzle and an oscillation device including an oscillation generation device configured to generate an oscillation upon the thin film and an oscillation amplification device which has an oscillation surface including a position that is parallel and opposite to the thin film and is configured to amplify the oscillation, periodically forming a droplet of the toner composition solution including at least a resin and a coloring agent to be supplied between the thin film and the oscillation surface and discharging the droplet via the nozzle, and solidifying the droplet of the toner composition solution discharged via the nozzle, and forming a toner particle.
    Type: Application
    Filed: March 10, 2009
    Publication date: September 10, 2009
    Inventors: Yoshihiro NORIKANE, Shinji AOKI, Tetsuya SONODA, Keisuke UCHIDA
  • Publication number: 20090226833
    Abstract: There is provided an electrophotographic toner, which includes a binder resin and a colorant, wherein, with a total intensity (kcps) of all elements detected in the toner due to fluorescent X-ray measurement designated as A and an intensity of nitrogen designated as B, B/A is from about 0.01 to about 0.5, and a ratio of nitrogen measured by X-ray photoelectron spectrometry after ion etching at an accelerating voltage of 10 mV for 180 seconds is from about 0.1 atom % to about 7.5 atom %.
    Type: Application
    Filed: September 23, 2008
    Publication date: September 10, 2009
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Shuji SATO, Atsushi SUGAWARA, Eisuke IWAZAKI, Hiroshi NAKAZAWA, Masanobu NINOMIYA, Kazufumi TOMITA
  • Patent number: 7575840
    Abstract: The toner of the present invention is characterized in that the charges rise up rapidly, the charge quantity is not insufficient nor excessive, the photoreceptor contamination is minimized and the toner is endurable under harsh conditions and against the high stress usage. The magnetic particle contained in the toner is of average particle size 0.01 ?m through 0.50 ?m, is of octahedron shape that is a convex polyhedron surrounded by eight triangles as a basis, each of vertexes and edges of the octahedron being in a curved surface shape and having a portion that can be taken as a straight line on the outer periphery of a projected image of said octahedron. The sphericity of the toner is 0.94 through 0.98. Here, the sphericity is defined by C2/C1, where C1 is a circumferential length of an image projected on a plane and C2 is a circumferential length of an assumed circle area as same as that of the projected image. Further, a number content of the toner of particle size 0.6 ?m through 2.
    Type: Grant
    Filed: March 31, 2006
    Date of Patent: August 18, 2009
    Assignee: Kyocera Mita Corporation
    Inventors: Kouzou Teramoto, Yukinori Nakayama, Kousuke Satou, Hiroshi Mizuhata
  • Patent number: 7575839
    Abstract: The object is to provide a magnetic toner with which toner scattering, toner spent to carrier, development of scratch streaks by the magnetic brush on the photoreceptor drum can be prevented for a prolonged period and a good image characteristic (in image density and background fogging) can be maintained for a prolonged period, and an image forming method using the magnetic toner. A two-component developer comprising carriers and toner which contains magnetic particle at least in a binder resin thereof, the magnetic particle being of basically polyhedral shaped shape, vertexes and edges of said polyhedral shape being curved surfaces, said shape having peripheral parts taken as straight lines in a projected image thereof, saturation magnetization of said toner in a magnetic field of 79.6 kA/m being 4.0 to 15.
    Type: Grant
    Filed: March 30, 2006
    Date of Patent: August 18, 2009
    Assignee: Kyocera Mita Corporation
    Inventors: Yukinori Nakayama, Kousuke Satou, Kouzou Teramoto, Hiroshi Mizuhata
  • Patent number: RE41652
    Abstract: A toner and process for making the toner wherein each combined resin and colorant particle has an average size less than about 10 microns and wherein the surface additive particles averaging less than about 40 nanometers in size average greater than two (2) percent of the combined weight of resin and colorant in the toner and wherein the Additive Adhesion Force Distribution percent value after 12 kilojoules of energy is greater than 40 percent.
    Type: Grant
    Filed: June 4, 2009
    Date of Patent: September 7, 2010
    Assignee: Xerox Corporation
    Inventor: James M. Proper