By Polymerization Patents (Class 430/137.15)
  • Publication number: 20040175640
    Abstract: The invention provides an electrostatic charge image developing toner containing a fixing resin and a wax, characterized in that in a DSC curve measured by a differential scanning calorimeter for the wax, a maximum endothermic peak of endothermic peaks at temperature up is less than 70° C., on-set temperature attributable to the maximum endothermic peak is above 50° C., and lowest on-set temperature of on-set temperatures attributable to endothermic peaks except the maximum endothermic peak is in a range of from 30° C. to 40° C.
    Type: Application
    Filed: March 1, 2004
    Publication date: September 9, 2004
    Applicant: Hitachi Printing Solutions, Ltd.
    Inventors: Tsuneaki Kawanishi, Junji Kobayashi, Ryuuichi Shimizu, Shigenori Yaguchi, Hirobumi Ouchi
  • Patent number: 6787280
    Abstract: A toner for developing an electrostatic image, comprising toner particles each containing at least a colorant and a resin, and an external additive present on each of the toner particles, wherein the water wettability of said toner particles without the external additive is W0, wherein the water wettability of the toner is W100, and wherein (W100−W0)/W100 is not greater than 0.3.
    Type: Grant
    Filed: November 4, 2002
    Date of Patent: September 7, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Yamashita, Tsunemi Sugiyama, Shinichiro Yagi, Hiroshi Yamada, Masami Tomita, Toshiki Nanya, Shigeru Emoto, Naohiro Watanabe, Tadao Takigawa
  • Patent number: 6770411
    Abstract: A toner including a binder resin, a colorant, and a product of an iron compound containing an aromatic hydroxylcarboxylic acid as a ligand and represented by the formula (I) described in the specification, wherein the product has such a characteristic that a filtrate obtained by filtering a dispersion of 10 g of the product dispersed in 200 ml of purified water provides an electric conductivity of not greater than 600 &mgr;S/cm.
    Type: Grant
    Filed: March 28, 2002
    Date of Patent: August 3, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Minoru Masuda, Satoshi Mochizuki, Yasuo Asahina, Kazuhiko Umemura, Hideki Sugiura, Kohsuke Suzuki, Tomomi Tamura
  • Publication number: 20040146795
    Abstract: A toner is used in an image forming process employing a toner recycling system and contains at least a modified polyester resin, a coloring agent, and a releasing agent. The toner has a volume-average particle diameter Dv, a number-average particle diameter Dn and a shape factor SF-1, wherein Dv is in a range from 4.0 &mgr;m to 6.0 &mgr;m, the ratio Dv/Dn of Dv to Dn is in a range from 1.00 to 1.30, and the shape factor SF-1 is in a range from 140 to 200.
    Type: Application
    Filed: January 20, 2004
    Publication date: July 29, 2004
    Inventors: Shigeru Emoto, Toshiki Nanya, Naohito Shimota, Maiko Kondo, Shinichiro Yagi, Hiroto Higuchi, Fumihiro Sasaki, Takahiro Honda, Junichi Awamura
  • Publication number: 20040142264
    Abstract: A toner including a thermoplastic resin; a colorant; a wax; and a crystalline polymer, wherein a DSC endothermic peak temperature of the wax or the crystalline polymer determined by subjecting the toner to a differential scanning calorimetric analysis is lower by not less than 2° C. than a DSC endothermic peak temperature thereof determined when only the wax or the crystalline polymer is subjected to the differential calorimetric analysis.
    Type: Application
    Filed: November 13, 2003
    Publication date: July 22, 2004
    Inventors: Chiaki Tanaka, Naohiro Watanabe, Takeshi Takada
  • Publication number: 20040131961
    Abstract: A toner composition including toner particles including a binder resin including a modified polyester resin, and a second resin having a weight average molecular weight of from 2,000 to 10,000; a colorant; a release agent; and a particulate material which is present at least a surface portion of the toner particles while embedded into the surface portion, wherein the binder resin has a glass transition temperature not lower than 35° C. and lower than 55° C., and wherein the particulate material has an average particle diameter of from 0.002 to 0.2 times that of the toner particles. A developer including the toner composition and a carrier having a layer thereon which includes at least an acrylic resin and a silicone resin, and a method for fixing an image of the toner composition are also provided.
    Type: Application
    Filed: September 26, 2003
    Publication date: July 8, 2004
    Applicant: RICOH COMPANY LIMITED
    Inventors: Yohichiroh Watanabe, Masanori Suzuki, Tsunemi Sugiyama, Hiroshi Yamashita, Takuya Saito, Naohiro Watanabe, Masami Tomita, Shigeru Emoto, Shinichiro Yagi, Hiroshi Yamada, Toshiki Nanya, Tadao Takigawa
  • Publication number: 20040121256
    Abstract: A color toner which gives a suitable image gloss and has an excellent color reproducibility, which has sufficient anti-offset properties even when a release oil is not coated on a fixing roller or is coated in only a small amount, and which has excellent transfer properties, durability, and charge stability relative to humidity is disclosed. Also, an image-forming apparatus using the color toner and a toner container filled with the color toner are disclosed. The color toner comprises a continuous phase of a resin containing a urea-modified polyester resin; and a modified resin dispersed in the continuous phase, wherein the modified resin contains a release polymer portion containing a release polymer; and a modified portion containing a plurality of vinyl monomer units, the modified portion having an average ester group concentration of 8% by weight to 30% by weight.
    Type: Application
    Filed: August 26, 2003
    Publication date: June 24, 2004
    Inventors: Masanori Suzuki, Takuya Saito, Hiroshi Yamashita, Yohichiroh Watanabe, Takeshi Takada, Tsunemi Sugiyama, Satoshi Mochizuki, Yasuaki Iwamoto, Takayuki Koike
  • Publication number: 20040110077
    Abstract: The present invention provides a silica fine particle capable of preventing a charging member or an image bearing member from being contaminated with toner when the toner contains the particle and also capable of providing the toner with a stable developing property. The silica fine particle of the present invention has been hydrophobic treated. Furthermore, the particle has a peak in a range of 0.04 &mgr;m to 1 &mgr;m and a peak in the range of 1 &mgr;m to 100 &mgr;m in a volume-basis particle diameter distribution. The particle has a frequency ratio of 10 to 80% for the particles with a particle diameter of 0.04 &mgr;m to 1 &mgr;m to a total of all the peaks, and the particles has the frequency ratio of less than 16% for the particles with a particle diameters of 20 &mgr;m to 2000 &mgr;m to the total of all the peaks.
    Type: Application
    Filed: October 2, 2003
    Publication date: June 10, 2004
    Inventors: Shinya Yachi, Yushi Mikuriya, Katsuyuki Nonaka, Shuntaro Watanabe
  • Publication number: 20040110081
    Abstract: Methods for producing a polymerized toners are provided, where, a dispersion including colored polymer particles obtained by polymerizing a polymerizable composition is treated stably in the process of reducing the remaining monomer, the resultant polymerized toners include a sufficiently low content of remaining monomer, and the resultant polymerized toners have excellent properties and are useful as developers for printing and copying. In the process of reducing the remaining monomer, the dispersion of the colored polymer particles is treated by stripping in the presence of a specific antifoaming agent.
    Type: Application
    Filed: July 31, 2003
    Publication date: June 10, 2004
    Inventors: Katsutomo Tanaka, Makoto Watanabe, Keita Sensui
  • Patent number: 6746809
    Abstract: A toner for development of electrostatic images which has a residual polymerizable monomer content lower than 70 ppm and is substantially spherical as demonstrated by the flowability of at least 55%, and a process for producing a toner reduced in residual polymerizable monomer content by subjecting a slurry containing polymer particles obtained by polymerization to a stripping treatment under reduced pressure.
    Type: Grant
    Filed: January 7, 2002
    Date of Patent: June 8, 2004
    Assignee: Nippon Zeon Co., Ltd.
    Inventors: Kazuhiro Sato, Takeo Fujino
  • Patent number: 6740460
    Abstract: A dry toner for developing an electrostatic image, including a toner binder containing a urea-modified polyester. The toner has a volume average particle diameter Dv of 3 to 10 &mgr;m and a number average particle diameter Dp such that the ratio Dv/Dp of the volume average particle diameter to the number average particle diameter ranges from 1.05 to 1.25.
    Type: Grant
    Filed: September 17, 2002
    Date of Patent: May 25, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Masami Tomita, Shigeru Emoto, Hiroshi Yamasita, Tsunemi Sugiyama
  • Publication number: 20040096767
    Abstract: In a process for producing toner particles by pre-dispersing at least a colorant and/or a release agent in a first dispersion medium to prepare a first fluid mixture, preparing a second fluid mixture from the first fluid mixture by means of a fine-dispersion machine, and forming toner particles from the second fluid mixture;
    Type: Application
    Filed: November 7, 2003
    Publication date: May 20, 2004
    Inventors: Yoshinori Tsuji, Hidekazu Fumita
  • Publication number: 20040072089
    Abstract: A toner containing a binder resin, a colorant, a charge control agent, and a thiazolyl disulfide compound or a thiuram disulfide compound. A process for producing a toner comprising polymerization of a polymerizable monomer composition that contains a polymerizable monomer and a colorant in an aqueous medium in the presence of a compound selected from a group consisting of (1) a thiazol thio compound, (2) a thiuram compound and (3) a dithiocarbamate compound.
    Type: Application
    Filed: September 25, 2003
    Publication date: April 15, 2004
    Inventors: Takuji Kishimoto, Rieko Takahara
  • Publication number: 20040072092
    Abstract: A toner for developing a static image is disclosed. The toner has carboxyl group in an amount of from 0.1×10−5 to 2.0×10−5 moles/g in a condition that the toner particle is dispersed in water, and an amount of a metal element contained in the toner is from 10 to 5,000 ppm by weight based on the toner.
    Type: Application
    Filed: May 23, 2003
    Publication date: April 15, 2004
    Inventors: Asao Matsushima, Hiroyuki Kozuru, Tomoe Kitani, Tomoko Tanma
  • Publication number: 20040067429
    Abstract: The present invention relates to an electrostatic-latent-image developing toner which contains at least a binder resin, a coloring agent and a wax that does not exhibit a clear peak on a low-temperature side of a main fusing peak in a DSC curve, the wax being represented by the formula;
    Type: Application
    Filed: January 29, 2003
    Publication date: April 8, 2004
    Applicant: Minolta Co., Ltd.
    Inventors: Hideaki Ueda, Shino Hirao, Masahiro Anno
  • Publication number: 20040053155
    Abstract: Disclosed is an electrophotographic toner using a polyester resin as a binder and a highly dispersed pigment colorant. The toner gives a high quality image excellent in transparency and chroma (brightness, gloss) and exhibits excellent powder fluidity, anti-offset property, charge stability and transferability.
    Type: Application
    Filed: July 7, 2003
    Publication date: March 18, 2004
    Inventors: Shigeru Emoto, Masami Tomita, Hiroshi Yamashita, Tsunemi Sugiyama
  • Publication number: 20040048184
    Abstract: A method of manufacturing polymer particles for use in a toner capable of incorporating fine wax particle in a polymer resin particle also in a case of adopting a dispersion polymerization method used generally so far, thereby enabling to prevent offset in a heat fixing device provided to copying machines or printers thereby improving the fixing property of the toner and capable of forming images at fine fineness when the polymer resin particles are used as the toner. The fine wax particle is dispersed by using the polymeric dispersant into an organic solvent and one or more of monomers for forming the polymer is dissolved and the polymerizing reaction of the monomer is proceeded while depositing the fine polymer particles on the surface of the fine wax particle upon deposition of the polymer into the organic solvent in the initial stage of the polymerizing reaction of the monomer, thereby incorporating the fine wax particles into the formed polymer particle.
    Type: Application
    Filed: June 26, 2003
    Publication date: March 11, 2004
    Applicant: BROTHER KOGYO KABUSHIKI KAISHA
    Inventors: Naomichi Kobayashi, Masato Tanaka
  • Patent number: 6689525
    Abstract: A dispersing agent for a pigment, comprising a specific compound having a structure wherein a phthalocyanine type molecular skeleton which is adsorptive on the pigment and an oligomer unit or polymer unit which prevents re-agglomeration of the pigment to bring out the effect of dispersion are covalently bonded, and having affinity for a medium or a solvent. Also disclosed are a pigment-dispersion composition containing the dispersing agent, a toner prepared using a pigment having been treated with the dispersing agent, and a process for producing such a toner.
    Type: Grant
    Filed: February 6, 2002
    Date of Patent: February 10, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hitoshi Itabashi
  • Publication number: 20030232269
    Abstract: A process for producing toner particles, in which toner particles are produced by polymerizing a polymerizable monomer composition containing at least a polymerizable monomer in an aqueous medium in a vessel, is provided. In this process, a resin composition containing a THF-insoluble resin component, which is a resin component generated in the process for producing toner particles, is kneaded. Then, the kneaded material and the polymerizable monomer are mixed together, and the resulting polymerizable monomer is polymerized to produce toner particles. For the resin composition, toner particles different from those having desired property, deposits on the vessel where the polymerization reaction occurred, or the like is used.
    Type: Application
    Filed: April 24, 2003
    Publication date: December 18, 2003
    Inventors: Takeshi Tsujino, Hitosi Kanda, Ryoichi Fujita, Yoshinori Tsuji
  • Publication number: 20030224276
    Abstract: To provide a process for producing toner particles in a good efficiency which have less residue of monomers and less other organic volatile components, the process has a polymerization step of polymerizing a polymerizable monomer composition containing at least a polymerizable monomer, in a vessel holding therein an aqueous medium, wherein a high-temperature saturated steam with a temperature higher than 100° C. is introduced into the aqueous medium held in the vessel, at the latter half of polymerization or after the polymerization has been completed, to remove at least organic volatile components from toner particles having at least a binder resin and a colorant.
    Type: Application
    Filed: January 24, 2003
    Publication date: December 4, 2003
    Inventors: Yoshinori Tsuji, Toshiyuki Ugai, Akira Hashimoto, Hidekazu Fumita
  • Publication number: 20030203300
    Abstract: An electrostatic image developing toner is disclosed. The toner is composed of a colored particle containing a compound represented by Formula (1).
    Type: Application
    Filed: April 3, 2003
    Publication date: October 30, 2003
    Inventors: Tomoe Kitani, Hiroshi Yamazaki, Ken Ohmura
  • Publication number: 20030186150
    Abstract: A toner for developing a static latent image is disclosed.
    Type: Application
    Filed: March 4, 2003
    Publication date: October 2, 2003
    Applicant: Konica Corporation
    Inventors: Ryuji Kitani, Asao Matsushima, Tomoe Kitani
  • Publication number: 20030180644
    Abstract: A toner for developing an electrostatic image, including a colorant, a binder resin comprising a modified polyester, and fine resin particles having a weight average particle diameter of 50 to 300 nm and being present on an outer surface of the toner, wherein the toner has a BET specific surface area of 1.5 to 4.0 m2/g.
    Type: Application
    Filed: March 24, 2003
    Publication date: September 25, 2003
    Inventors: Toshiki Nanya, Masami Tomita, Shigeru Emoto, Hiroshi Yamada, Shinichiro Yagi, Naohiro Watanabe, Tadao Takigawa
  • Publication number: 20030180641
    Abstract: A toner for developing an electrostatic latent image is provided that can prevent occurrence of blister even with coated paper having a coated surface, exhibits excellent releasing performance in oilless fixing, and realizes both high glossiness and OHP transparency for an image to be formed. A process for producing the toner, a developer containing the toner, and a process for forming an image using the toner are also provided. The toner for developing an electrostatic latent image contains a binder resin, a releasing agent and a colorant, in which the binder resin has a number average molecular weight (Mn) in a range of from 9,000 to 18,000 and a molecular weight distribution represented by a ratio (Mw/Mn) of a weight average molecular weight (Mw) and a number average molecular weight (Mn) of 2.5 or less, and the binder resin contains a vinyl resin.
    Type: Application
    Filed: August 16, 2002
    Publication date: September 25, 2003
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Tomohito Nakajima, Satoshi Yoshida, Hidekazu Yaguchi, Takahisa Fujii, Yasuo Matsumura
  • Publication number: 20030181551
    Abstract: It is an object of the present invention to provide a dispersing agent for a pigment capable of finely dispersing a pigment in a dispersion medium. The present invention provides a dispersing agent for a pigment comprising at least a metallic compound having a specific structure with a central metal capable of taking a penta-coordinated structure, and n-electron-donating compound having affinity for the dispersion medium and capable of being coordinated with the central metal of the metallic compound.
    Type: Application
    Filed: January 10, 2003
    Publication date: September 25, 2003
    Inventors: Norikazu Fujimoto, Hitoshi Itabashi
  • Publication number: 20030175610
    Abstract: An electrostatic image developing toner comprising a resin and a colorant is disclosed. The resin comprises a polymerization component of a polymerizable monomer having a polar group in an amount of 1.0 to 10.0 percent by weight, and a polymerization component of a polyfunctional polymerizable monomer in an amount of 0.1 to 10.0 percent by weight; ratio (A/B) is from 0.5 to 20.0 percent; and either a peak or a shoulder is positioned in the molecular weight region of 5,000 to 20,000, wherein A is an area of a chromatograph curve in the molecular weight region of 60,000 to 1,000,000, based on GCP measurement of a THF soluble component of toner and B is an entire area of the chromatograph curve.
    Type: Application
    Filed: December 2, 2002
    Publication date: September 18, 2003
    Inventors: Tomoe Kitani, Takao Yamanouchi, Naohiro Hirose, Ken Ohmura
  • Publication number: 20030170557
    Abstract: A non-magnetic mono-component toner of the present invention comprises, at least, a plurality of mother particles and a plurality of CCA particles adhering to the mother particles. The non-magnetic mono-component toner satisfies a×d<2.5, wherein “a” is the inclination of an approximation straight line of the CCA particles adhering to the mother particles, obtained by approximating distribution of particle diameter of the CCA particles relative to the particle diameter of the mother particles by the least-square method, and “d” (&mgr;m) is the volume-based mean particle diameter of the toner. Therefore, the charge on one particle of the non-magnetic mono-component toner can be efficiently reduced, thereby allowing lower developing voltage and achieving reduction in developing hysteresis.
    Type: Application
    Filed: February 24, 2003
    Publication date: September 11, 2003
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Hiroshi Toyama
  • Publication number: 20030162112
    Abstract: A toner for developing an electrostatic image, comprising toner particles each containing at least a colorant and a resin, and an external additive present on each of the toner particles, wherein the water wettability of said toner particles without the external additive is W0, wherein the water wettability of the toner is W100, and wherein (W100−W0)/W100 is not greater than 0.3.
    Type: Application
    Filed: November 4, 2002
    Publication date: August 28, 2003
    Inventors: Hiroshi Yamashita, Tsunemi Sugiyama, Shinichiro Yagi, Hiroshi Yamada, Masami Tomita, Toshiki Nanya, Shigeru Emoto, Naohiro Watanabe, Tadao Takigawa
  • Publication number: 20030134220
    Abstract: A toner composition including toner particles including mother toner particles, which include a binder resin, a colorant and a release agent, and a charge controlling agent which is located on a surface of the mother toner particles and fixed thereon, wherein the toner particles have a spherical degree of from 0.960 to 1.000 and a specific surface area of from 0.70 to 2.5 m2/g. The toner composition optionally includes an external additive which is present on the surface of the toner particles.
    Type: Application
    Filed: September 19, 2002
    Publication date: July 17, 2003
    Inventors: Shigeru Emoto, Hiroshi Yamashita, Naohiro Watanabe, Tsunemi Sugiyama, Hiroshi Yamada, Masami Tomita
  • Publication number: 20030113648
    Abstract: A dry toner for developing an electrostatic image, including a toner binder containing a urea-modified polyester. The toner has a volume average particle diameter Dv of 3 to 10 &mgr;m and a number average particle diameter Dp such that the ratio Dv/Dp of the volume average particle diameter to the number average particle diameter ranges from 1.05 to 1.25.
    Type: Application
    Filed: September 17, 2002
    Publication date: June 19, 2003
    Inventors: Masami Tomita, Shigeru Emoto, Hiroshi Yamasita, Tsunemi Sugiyama
  • Publication number: 20030073020
    Abstract: A toner production process comprising the step of polymerizing a polymerizable monomer in the presence of (i) base particles containing at least a binder resin and (ii) a polymerization initiator. The polymerization initiator has in one molecule a hydrophilic moiety and a hydrophobic moiety and a reactive moiety between them, and the base particles are enlarged and/or surface-modified upon polymerization of the polymerizable monomer. Also disclosed is a toner having a circularity of from 0.92 to 1.0, which is produced by this process.
    Type: Application
    Filed: May 23, 2002
    Publication date: April 17, 2003
    Inventors: Yasukazu Ayaki, Hitoshi Itabashi, Yayoi Tazawa
  • Publication number: 20030044707
    Abstract: A dispersing agent for a pigment, comprising a specific compound having a structure wherein a phthalocyanine type molecular skeleton which is adsorptive on the pigment and an oligomer unit or polymer unit which prevents re-agglomeration of the pigment to bring out the effect of dispersion are covalently bonded, and having affinity for a medium or a solvent. Also disclosed are a pigment-dispersion composition containing the dispersing agent, a toner prepared using a pigment having been treated with the dispersing agent, and a process for producing such a toner.
    Type: Application
    Filed: February 6, 2002
    Publication date: March 6, 2003
    Inventor: Hitoshi Itabashi
  • Publication number: 20030022082
    Abstract: The present invention relates to a toner for developing a static latent image, wherein a smell of the toner has a cos&thgr; of from 0.990 to 0.998 as to the smell of styrene and a cos&thgr; of from 0.986 to 0.994 as to the smell of n-butyl acrylate in the smell space formed by styrene and n-butyl acrylate, and a toner for developing a static latent image, wherein a smell of the toner has a cos &thgr; of from 0.990 to 0.998 as to the smell of styrene and a cos &thgr; of from 0.991 to 0.999 as to the smell of mercaptocarboxylic acid ester in the smell space formed by styrene and mercaptocarboxylic acid ester.
    Type: Application
    Filed: June 5, 2002
    Publication date: January 30, 2003
    Inventors: Ken Ohmura, Naohiro Hirose, Hiroshi Yamazaki
  • Patent number: 6506529
    Abstract: A toner for developing an electrostatic latent image comprising a resin, a colorant and a releasing agent is disclosed. The releasing agent comprises a mixture of a plurality of compounds represented by formula (1) having difference carbon number of carbon atoms in R2 R1—(OCO—R2)n  (1) wherein n represents an integer of 1 to 8 carbon atoms which may has a substituent, R1 is a hydrocarbon group having from 1 to 40, R2 is a hydrocarbon group having from 8 to 40 carbon atoms which may has a substituent.
    Type: Grant
    Filed: September 17, 2001
    Date of Patent: January 14, 2003
    Assignee: Konica Corporation
    Inventors: Masafumi Uchida, Hiroshi Yamazaki, Meizo Shirose, Hajime Tadokoro, Ken Ohmura
  • Patent number: 6500593
    Abstract: In a toner containing at least a binder resin, a pigment and a pigment dispersant, the pigment dispersant has a structure wherein a quinacridone molecular skeleton which is readily adsorptive on the colorant pigment and an oligomer or polymer which has good affinity for the solvent and for the resin serving as a toner binder are covalently bonded. Also disclosed is a process for producing the toner.
    Type: Grant
    Filed: November 29, 2001
    Date of Patent: December 31, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Koji Abe, Hitoshi Itabashi
  • Patent number: 6495648
    Abstract: Toner binder resins with low odor and excellent charging stability as toners, containing styrene-acrylic copolymers or mixtures thereof, wherein the total content of volatile components is no greater than about 1,500 ppm, the content of volatile components with benzene rings is no greater than about 1,400 ppm, and the content of volatile components with benzene rings and boiling point of below about 200° C. is no greater than about 500 ppm.
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: December 17, 2002
    Assignee: Mitsubishi Rayon Co., Ltd.
    Inventors: Motoshi Inagaki, Koji Shimizu, Yoko Harada, Junya Nakamura
  • Patent number: 6458502
    Abstract: A process for producing a polymerization toner, which comprises preparing a polymerizable-monomer composition which contains at least a polymerizable monomer and a colorant and does not contain any polymerization initiator, i) introducing the polymerizable-monomer composition into an aqueous medium to effect granulation, adding a polymerization initiator to the aqueous medium in the course of the granulation or after the granulation has been completed, or ii) adding a polymerization initiator in an aqueous medium, introducing the polymerizable-monomer composition into the aqueous medium to effect granulation, and then polymerizing the polymerizable-monomer composition having been granulated, to produce toner particles. In the process, the polymerization initiator is added in a specific time and a specific manner.
    Type: Grant
    Filed: June 7, 2001
    Date of Patent: October 1, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tatsuya Nakamura, Hiroaki Kawakami, Koji Inaba, Yuji Moriki, Satoshi Handa, Katsuyuki Nonaka
  • Patent number: 6455219
    Abstract: A process for making silica-containing latex particles involves polymerizing monomer in an emulsion comprising the monomer, water, silica particles, and optionally at least one surfactant, by adding at least one free radical initiator to the emulsion to form the silica-containing latex particles. In a preferred method, semicontinuous polymerization employing a seed latex is used to form the latex resin. The process achieves a silica-containing latex in which the silica is chemically incorporated therein that is ideally suited for use in the manufacture of toner and developer for xerographic use.
    Type: Grant
    Filed: June 22, 2001
    Date of Patent: September 24, 2002
    Assignee: Xerox Corporation
    Inventors: Allan K. Chen, Tie Hwee Ng, Arthur Helbrecht, Kimberly D. Nosella, Danielle C. Boils-Boissier, Paul J. Gerroir, Rosa M. Duque
  • Patent number: 6432605
    Abstract: A process for preparing a dispersion polymerized color toner for developing latent electrostatic images includes polymerization of a macromer in a liquid organic medium in which the macromer or the resulting polymer resin is not soluble. The liquid organic medium comprises a polymeric dispersion stabilizer. A macromer mixture comprising macromer, a colorant and a charge control agent may be polymerized in the dispersed state to produce the toner. Alternatively, the macromer is polymerized in the dispersed state to produce a particulate polymer resin. The particulate polymer resin formed is a functionalized resin having sites suitable for interacting with functionalized dyes that have complementary functionality. The functionalized dye is then applied to the resin particles typically with a dyeing aid, or surfactant. Toners produced by the inventive processes are substantially free of contamination by the liquid organic medium used during dispersion polymerization and/or dispersion dyeing.
    Type: Grant
    Filed: December 31, 2001
    Date of Patent: August 13, 2002
    Assignee: MatSci Solutions, Inc.
    Inventor: Hyun-Nam Yoon
  • Publication number: 20020102485
    Abstract: In a toner containing at least a binder resin, a pigment and a pigment dispersant, the pigment dispersant has a structure wherein a quinacridone molecular skeleton which is readily adsorptive on the colorant pigment and an oligomer or polymer which has good affinity for the solvent and for the resin serving as a toner binder are covalently bonded. Also disclosed is a process for producing the toner.
    Type: Application
    Filed: November 29, 2001
    Publication date: August 1, 2002
    Inventors: Koji Abe, Hitoshi Itabashi
  • Patent number: 6403273
    Abstract: Toner particulates comprise a styrene/acrylic copolymer having a first aliphatic hydrocarbon wax incorporated therein during polyermization of the copolymer, and a second aliphatic hydrocarbon wax mixed with the copolymer.
    Type: Grant
    Filed: February 9, 2001
    Date of Patent: June 11, 2002
    Assignee: Lexmark International, Inc.
    Inventors: Vincent Wen-Hwa Ting, Michael Thomas Moore
  • Patent number: 6383700
    Abstract: In an electrostatic image forming method, said electrophotographic photoreceptor comprises a resinous layer comprising siloxane base resin containing a structural unit having charge transport performance and a cross-linked structure on an electrically conductive support, and developer material comprises a toner which is obtained by suspension-polymerizing a polymerizable composition comprised of at least polymerizing monomer and colorant or a toner which is obtained by fusing at least said resin particles in an aqueous medium.
    Type: Grant
    Filed: October 13, 2000
    Date of Patent: May 7, 2002
    Assignee: Konica Corporation
    Inventors: Hiroshi Yamazaki, Hiroyuki Yamada, Meizo Shirose, Shigenori Kouno, Akihiko Itami
  • Patent number: 6383702
    Abstract: A dry toner of polymerization type for electronic photography for forming an image on a recordable medium is synthesized during a polymerization process by adding a hydrophobic silica system compound having both hydrophobic groups and hydrophilic groups and having the following chemical structure formula: the silica system compound being a stabilizer in a polymerization composition.
    Type: Grant
    Filed: October 13, 2000
    Date of Patent: May 7, 2002
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Seung-Min Ryu, Seung-Soon Jang, Soon-Nam Kim, Jong-Moon Eun, Hee-Won Jung, Moon-Soo Park, Soon-Gil Hong
  • Patent number: 6365318
    Abstract: Disclosed is a process which comprises (a) dispersing into a solvent (i) toner particles comprising a resin and an optional colorant, and (ii) monomers selected from pyrroles, thiophenes, or mixtures thereof; and (b) causing, by exposure of the monomers to an oxidant, oxidative polymerization of the monomers onto the toner particles, wherein subsequent to polymerization, the toner particles are capable of being charged to a negative or positive polarity, and wherein the polarity is determined by the oxidant selected.
    Type: Grant
    Filed: November 28, 2000
    Date of Patent: April 2, 2002
    Assignee: Xerox Corporation
    Inventors: Karen A. Moffat, Maria N. V. McDougall, James R. Combes
  • Publication number: 20020034703
    Abstract: A toner for developing electrostatic latent image is disclosed. The toner comprise of particles having a volume average particle diameter of from 3 to 8 &mgr;m, and said resin is obtained by either emulsion polymerization, mini-emulsion polymerization employing or suspension polymerization employing thioglycerin or at least one compound selected from compounds represented by the Formula (1) as the chain transfer agent.
    Type: Application
    Filed: July 17, 2001
    Publication date: March 21, 2002
    Inventors: Hiroshi Yamazaki, Kenji Yamane, Hiroyuki Kozuru, Kenji Hayashi, Mikio Kohyama
  • Patent number: 6355392
    Abstract: A process for preparing a dispersion polymerized color toner for developing latent electrostatic images includes polymerization of a macromer in a liquid organic medium in which the macromer or the resulting polymer resin is not soluble. The liquid organic medium comprises a polymeric dispersion stabilizer. A macromer mixture comprising macromer, a colorant and a charge control agent may be polymerized in the dispersed state to produce the toner. Alternatively, the macromer is polymerized in the dispersed state to produce a particulate polymer resin. The particulate polymer resin formed is a functionalized resin having sites suitable for interacting with functionalized dyes that have complementary functionality. The functionalized dye is then applied to the resin particles typically with a dyeing aid, or surfactant. Toners produced by the inventive processes are substantially free of contamination by the liquid organic medium used during dispersion polymerization and/or dispersion dyeing.
    Type: Grant
    Filed: August 7, 2000
    Date of Patent: March 12, 2002
    Assignee: MatSci Solutions, Inc.
    Inventor: Hyun-Nam Yoon
  • Patent number: 6342328
    Abstract: A toner for development of electrostatic images, comprising at least a binder resin, a colorant and a charge control agent, wherein the charge control agent is a polar resin composed of a copolymer of a vinyl monomer and SO3X (X=H or alkali metal) group-containing (meth)acrylamide and having an SO3X group-containing (meth)acrylamide unit content of 0.1 to 10 wt. % and a weight average molecular weight of 17,000 to 25,000, and a production process of the toner.
    Type: Grant
    Filed: September 5, 2000
    Date of Patent: January 29, 2002
    Assignee: Nippon Zeon Co., Ltd.
    Inventors: Takahiro Takasaki, Kazu Niwa, Kojiro Masuo, Kazuhiro Sato