One Component Toner Patents (Class 430/903)
  • Patent number: 7105260
    Abstract: A binder resin for a toner comprises a polyester component having a specific structure which is not soluble in tetrahydrofuran, and a polyester component having a specific branched structure which is soluble in tetrahydrofuran. The binder resin can provide a toner, which is superior in low-temperature fixation and offset resistance and can be used in high speed printing in response to the recent market demands owing to its specific structure.
    Type: Grant
    Filed: May 30, 2003
    Date of Patent: September 12, 2006
    Assignee: Mitsui Chemicals, Inc.
    Inventors: Tomoya Terauchi, Hirotaka Uosaki, Hiroshi Matsuoka, Yuji Emura, Hiroyuki Takei, Hironobu Hashimoto
  • Publication number: 20020106572
    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: December 6, 2001
    Publication date: August 8, 2002
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Hiroshi Toyama
  • Publication number: 20010044070
    Abstract: A chemical amplification type positive resist composition excellent in balance of properties such as resolution, profile, sensitivity, dry etching resistance, adhesion and the like which comprises a resin which has the following polymeric units (A), (B) and (C); and an acid generating agent.
    Type: Application
    Filed: April 3, 2001
    Publication date: November 22, 2001
    Inventors: Yasunori Uetani, Airi Yamada, Yoshiko Miya, Yoshiyuki Takata
  • Patent number: 6174639
    Abstract: Disclosed are a positive charging color toner comprising a coloring agent and a positive charging electric charge controlling material in a fixing resin, wherein the fixing rein is an urethane-modified polyester resin having an acid value of not more than 5 KOHmg/g, a hydroxyl value of not more than 9 KOHmg/g, a weight-average molecular weight of 8,000 to 120,000 and a number-average molecular weight of 2,000 to 70,000, and the positive charging electric charge controlling material is (a) a quaternary ammonium salt having a melting point of not less than 200° C., or (b) a styrene-acrylate copolymer having a trisubstituted amminio group and a glass transition temperature Tg of not less than 55° C.
    Type: Grant
    Filed: March 31, 2000
    Date of Patent: January 16, 2001
    Assignee: Mita Industrial Co., Ltd.
    Inventors: Yoshitake Shimizu, Takahiro Ishihara, Hiroshi Shimoyama, Toyotsune Inoue, Takashi Nishino, Kazuya Nagao, Kenshi Matsui, Takayuki Itakura, Norio Horikami
  • Patent number: 6159647
    Abstract: The present invention relates to a non-magnetic yellow toner for use in full-color image forming apparatuses, such as full-color electrostatic copying machines and full-color laser beam printers, comprising:non-magnetic toner particles containing a binder resin having an acid value of 1 to 30 KOHmg/g, and a coloring material composed of a compound classified as C. I. pigment yellow 180;the toner particles having a roundness of 0.94 to 1.0, a standard roundness deviation of not more than 0.045, and a volume mean particle size of 2 to 9 .mu.m.
    Type: Grant
    Filed: August 3, 1998
    Date of Patent: December 12, 2000
    Assignee: Minolta Co., Ltd.
    Inventors: Masahiro Anno, Chikara Tsutsui, Minoru Nakamura, Katsunori Kurose, Hiroyuki Fukuda
  • Patent number: 6124071
    Abstract: A toner comprised of polymer and titanium oxide dihydroxide of the formula --O--Ti(OH).sub.2 wherein Ti is titanium.
    Type: Grant
    Filed: March 1, 1999
    Date of Patent: September 26, 2000
    Assignee: Xerox Corporation
    Inventors: Pinyen Lin, Carol A. Fox, Roger N. Ciccarelli
  • Patent number: 6106986
    Abstract: A color toner comprising (A) a resin binder comprising a polyester, as a main component, obtained by polycondensing a polyhydric alcohol component and a carboxylic acid component, wherein the polyhydric alcohol component comprises a compound represented by the formula (I): wherein R.sup.1 is an alkylene group having 2 to 4 carbon atoms; x and y are positive numbers, wherein a sum of x and y is from 1 to 16, in an amount of 5% by mol or more of an entire polyhydric alcohol component, and wherein the carboxylic acid component comprises 50% by mol or more of a dicarboxylic acid compound and 50% by mol or less of a tricarboxylic or higher polycarboxylic acid compound; (B) a releasing agent having an average diameter size of dispersed particles in the color toner of from 0.1 to 3 .mu.
    Type: Grant
    Filed: November 17, 1999
    Date of Patent: August 22, 2000
    Assignee: Kao Corporation
    Inventors: Eiji Shirai, Shinichi Sata, Toshihiro Hattori, Hironobu Nagasaki, Yoshifumi Tokuhisa
  • Patent number: 6096467
    Abstract: Disclosed are a positive charging color toner comprising a coloring agent and a positive charging electric charge controlling material in a fixing resin, wherein the fixing rein is an urethane-modified polyester resin having an acid value of not more than 5 KOHmg/g, a hydroxyl value of not more than 9 KOHmg/g, a weight-average molecular weight of 8,000 to 120,000 and a number-average molecular weight of 2,000 to 70,000, and the positive charging electric charge controlling material is (a) a quaternary ammonium salt having a melting point of not less than 200.degree. C., or (b) a styrene-acrylate copolymer having a trisubstituted amminio group and a glass transition temperature Tg of not less than 55.degree. C.
    Type: Grant
    Filed: November 12, 1998
    Date of Patent: August 1, 2000
    Assignee: Mita Industrial Co., Ltd.
    Inventors: Yoshitake Shimizu, Takahiro Ishihara, Hiroshi Shimoyama, Toyotsune Inoue, Takashi Nishino, Kazuya Nagao, Kenshi Matsui, Takayuki Itakura, Norio Horikami
  • Patent number: 6063535
    Abstract: A mono-component developing method, comprising the steps of:supplying a mono-component developing agent containing a toner onto a developer-supporting member that is aligned face to face with an image-supporting member;regulating the developing agent on the developer-supporting member by a regulating member installed in contact with the developer-supporting member; anddeveloping an electrostatic latent image formed on the image-supporting member by the toner,wherein the toner has a weight-average particle size (d.sub.50) in the range of 4 to 10 .mu.m, an average degree of roundness of not less than 0.950 and a standard deviation of degree of roundness of not more than 0.040, and more preferably the toner has a specific value of a surface shape characteristic D/d.sub.50, and a specific ratio d.sub.50 /Ra of the toner weight-average particle size (d.sub.50) to the surface roughness (Ra) of the developer-supporting member.
    Type: Grant
    Filed: April 13, 1999
    Date of Patent: May 16, 2000
    Assignee: Minolta Co., Ltd.
    Inventors: Chikara Tsutsui, Katsunori Kurose, Masahiro Anno, Minoru Nakamura, Hiroyuki Fukuda
  • Patent number: 5985506
    Abstract: A magnetic toner for use in electrophotographic development which can be endowed with high performance by subjecting it to surface treatment with hot air in its dispersed state. The magnetic toner is used in an electrophotographic system including a development process in which an electrostatic latent image is formed by using a photoconductive drum having a stationary magnet therein, and thereafter the magnetic toner is sucked in a toner sump by magnetic force, whereby non-image area toner is recovered by an electrode roller, and the electrophotographic system including a recycle process of the residual toner. The magnetic toner is capable of realizing high-quality image development and stable recycle of residual toner by subjecting the magnetic toner to surface treatment with hot air.
    Type: Grant
    Filed: May 24, 1996
    Date of Patent: November 16, 1999
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yasuhito Yuasa, Akinori Toyoda, Noriaki Hirota
  • Patent number: 5976748
    Abstract: A magnetic toner for a MICR printer containing a binder resin and a magnetic powder is prepared in such a way that the magnetic powder includes a first magnetic powder having a residual magnetization value within a range of 24 to 40 emu/g and a second magnetic powder having a residual magnetization value within a range of 1 to 24 emu/g (but exclusive of 24 m.sup.2 /g) and that the residual magnetization value of the magnetic toner for a MICR printer is within a range of 7.0 to 20 emu/g (but exclusive of 7.0 emu/g).
    Type: Grant
    Filed: November 3, 1998
    Date of Patent: November 2, 1999
    Assignee: Kyocera Corporation
    Inventors: Takaaki Arai, Tatsuya Yasui, Hiroaki Moriyama
  • Patent number: 5965312
    Abstract: A one-component developer comprising an external additive, and toner particles containing a binder resin and a colorant, wherein the external additive contains a titanium compound obtained by the reaction of TiO(OH).sub.2 and a silane compound, and an image forming method using the one-component developer are disclosed. The one-component developer and the image forming method provide excellent flow and a narrow charge distribution, can reduce fluctuation of the charge property due to the environmental change, and can thus form a high-quality image without fogging and the damage to a latent image retainer by filming can be prevented.
    Type: Grant
    Filed: May 15, 1997
    Date of Patent: October 12, 1999
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Hiroshi Nakazawa, Koutarou Yoshihara, Etsuo Tominaga, Hiroe Okuyama, Masahiro Uchida, Chiaki Suzuki, Yoshifumi Iida, Toyofumi Inoue, Hiroyoshi Okuno
  • Patent number: 5905010
    Abstract: The nonmagnetic toner for forming full color images of the present invention comprises:a binder resin, a colorant and wax dispersed in the binder resin as wax particles;wherein the wax particles contained in the toner have a particle size distribution in which the wax particles having a particle size of 3 .mu.m or more are less than 3% by number, the wax particles having a particle size ranging from 2 .mu.m to less than 3 .mu.m are less than 12% by number, the wax particles having a particle size ranging from 1 .mu.m to less than 2 .mu.m are 5% to 30% by number, and the wax particles having a particle size of less than 1 .mu.m are 55% to 95% by number.
    Type: Grant
    Filed: December 1, 1997
    Date of Patent: May 18, 1999
    Assignee: Minolta Co., Ltd.
    Inventors: Minoru Nakamura, Masahiro Anno, Chikara Tsutsui, Katsunori Kurose
  • Patent number: 5891600
    Abstract: The present invention provides a mono-component developer comprising toner particles containing a binding resin, a colorant and an additive and a method of forming images by use thereof. In the present invention said additive is preferably a titanium compound prepared by through the reaction between TiO(OH).sub.2 and a silane compound or through the reaction between TiO(OH).sub.2 and a silicone oil. The specific gravity of the said titanium compound is in the range of 2.8 to 3.6. The average particle diameter thereof is in the range of 10 to 70 nm. The said toner particle is preferably a non-magnetic particle. By making use of the mono-component developer and the method for forming an image using it, charging of the toner, and carriage of the toner can be stabilized over a long period of time, and stable image formation can be obtained.
    Type: Grant
    Filed: October 9, 1997
    Date of Patent: April 6, 1999
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Hiroyoshi Okuno, Etsuo Tominaga, Toyofumi Inoue, Tetsu Torigoe, Hiroe Okuyama, Takahisa Fujii, Koutarou Yoshihara, Masahiro Uchida, Hiroshi Nakazawa, Chiaki Suzuki, Yoshifumi Iida
  • Patent number: 5882832
    Abstract: A dry toner useful for one component developer developing method is provided which has good image qualities and durability without contamination of developing apparatus. The toner includes a metal oxide in an amount of from about 10 to about 30 parts by weight per 100 parts by weight of the toner and a metal-containing azo dye.
    Type: Grant
    Filed: April 11, 1997
    Date of Patent: March 16, 1999
    Assignee: Ricoh Company, Ltd.
    Inventors: Hachiroh Tosaka, Shoichi Sugimoto, Masahide Yamashita, Shinichiroh Yagi
  • Patent number: 5879849
    Abstract: A developing device using one component developer for developing an electrostatic latent image on a photoconductive drum. The one component developer includes particles of parents of toner, resin beads and silica. The silica adhere to a surface of each resin bead. The resin beads and the silica further adhere to a surface of the parents of toner. A volume average diameter of the resin beads is more than that of the silica and is less than that of the parents of toner.
    Type: Grant
    Filed: June 25, 1997
    Date of Patent: March 9, 1999
    Assignee: Ricoh Company, Ltd.
    Inventors: Akira Sawada, Kanjiroh Kawasaki, Shinichiro Yagi
  • Patent number: 5851713
    Abstract: Disclosed is a toner for developing an electrostatic latent image, said toner having a BET specific surface area of not less than 5m.sup.2 /g and a particle size distribution (2SD) of not more than 5 .mu.m.
    Type: Grant
    Filed: September 30, 1996
    Date of Patent: December 22, 1998
    Assignee: Konica Corporation
    Inventors: Kenji Hayashi, Mikio Koyama, Tomoe Kikuchi, Hiroshi Yamazaki, Naohiro Hirose, Shinichi Suzuki, Tsutomu Iwamoto, Yoshiki Nishimori
  • Patent number: 5849451
    Abstract: An electrophotographic dry toner comprising toner particles having externally added thereto fine particles of an inorganic compound having been surface treated with an amphoteric surface active agent. The toner is excellent in fluidity, anti-caking properties, charging properties, and environmental stability and provides excellent images free from defects such as black spots.
    Type: Grant
    Filed: July 17, 1997
    Date of Patent: December 15, 1998
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Yuka Ishihara, Chiaki Suzuki, Tetsu Torigoe, Atuhiko Eguchi, Takayoshi Aoki
  • Patent number: 5843605
    Abstract: The present invention relates to A yellow developer comprising:a non-magnetic toner particle containing colorant, binder resin and wax, the colorant being a compound classified into C. I. pigment yellow 180, the binder resin having an acid value of 1 to 30 KOH mg/g, and the wax having an acid value of 0.5 to 30 KOH mg/g.
    Type: Grant
    Filed: March 25, 1998
    Date of Patent: December 1, 1998
    Assignee: Minolta Co., Ltd.
    Inventors: Masahiro Anno, Katsunori Kurose, Hiroyuki Fukuda
  • Patent number: 5840460
    Abstract: A toner for developing electrostatic images is provided which has good adhesion resistance and good low temperature fixing property, and further can exhibit good image developing performance in various quality aspects including fog resistance, filming resistance, and image density. The toner includes at least a binder resin and a colorant and is characterized in that the toner, prepared as such, has a melt index range of 15 to 40 (g/10 minutes) at 125.degree. C. and the binder resin has a melt index range of 3 to 12 (g/10 minutes) at 150.degree. C.
    Type: Grant
    Filed: January 31, 1997
    Date of Patent: November 24, 1998
    Assignee: Minolta Co., Ltd
    Inventors: Junji Machida, Chikara Tsutsui
  • Patent number: 5840458
    Abstract: The present invention relates to a developer comprising toner to which laminated titanium oxide is externally added.
    Type: Grant
    Filed: February 13, 1996
    Date of Patent: November 24, 1998
    Assignee: Minolta Co., Ltd.
    Inventors: Kenichi Kido, Katsunori Kurose, Takeshi Arai, Masayuki Hagi
  • Patent number: 5800959
    Abstract: An electrostatic latent image developer is produced by adding 1 part by weight or more of an agent improving transfer efficiency, the agent having an average particle size of 0.1 to 3 .mu.m, together with 0.3 to 5 parts by weight of a hydrophobic silica fine powder of a BET specific surface area of 50 to 300 m.sub.2 /g to 100 parts by weight of a toner. The electrostatic latent image developer of the invention improves the transfer efficiency from a photosensitive material onto a recording medium while the flowability of the toner can be retained, whereby any cleaning mechanism in a developer system can be omitted.
    Type: Grant
    Filed: June 17, 1996
    Date of Patent: September 1, 1998
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Jun Ikami
  • Patent number: 5792583
    Abstract: The present invention provides a toner for developing an electrostatic latent image comprising:a colorant; and binder resin including a low-molecular component having a weight-average molecular weight from 3,000 to 15,000 which is obtained by gel permeation chromatography (GPC), said low-molecular component being included from 60 percent-by-weight to 80 percent-by-weight with respect to the binder resin.
    Type: Grant
    Filed: December 14, 1995
    Date of Patent: August 11, 1998
    Assignee: Minolta Co., Ltd.
    Inventors: Tetsuo Sano, Yoshitaka Sekiguchi
  • Patent number: 5783347
    Abstract: A positively chargeable single-component developer for visualizing electrostatic latent images comprises a binding resin having an acid value of 1.5 to 10 (KOH mg/g), a colorant, and an additive such as polyfluoroethylene fine powder having an electron attractive group. The additive is added in an amount of 0.05 part by weight to 2 parts by weight with respect to 100 parts by weight of the positively chargeable single-component developer. The acid value of the binding resin may be adjusted by mixing two or more resins having different acid values. The developer prevents a surface of a photosensitive member from decrease in electric potential which would be otherwise caused by electrons released when toner particles and the photosensitive member are frictionally charged. Accordingly, the developer makes it possible to provide good image quality with less fog and with a dense density.
    Type: Grant
    Filed: June 10, 1997
    Date of Patent: July 21, 1998
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Jun Ikami
  • Patent number: 5756244
    Abstract: The toner for full-color electrophotography usable for a fixing process by a heat roller, wherein a releasing oil is not applied on a surface of the heat roller, includes at least (a) a binder resin having as a main component a linear polyester obtainable using one or more monomers selected from the group consisting of saturated or unsaturated, aliphatic dicarboxylic acids, acid anhydrides thereof, and lower alkyl esters thereof as an acid component, provided that the saturated aliphatic dicarboxylic acids have carbon atoms of not less than 3, and that the unsaturated aliphatic dicarboxylic acids have carbon atoms of not less than 5, the linear polyester having a softening point of from 90.degree. to 120.degree. C. determined by "koka" type flow tester; (b) a releasing agent comprising carnauba wax; and (c) a coloring agent.
    Type: Grant
    Filed: February 2, 1996
    Date of Patent: May 26, 1998
    Assignee: Kao Corporation
    Inventors: Shinichiro Omatsu, Tetsuhiro Semura
  • Patent number: 5683845
    Abstract: The positively chargeable toner used for a nonmagnetic one-component developing method includes a toner particle and fine polytetrafluoroethylene particles, the toner particle having (a) a binder resin having a polyester resin having an acid value of 10 mg KOH/g or less; (b) a colorant; and (c) a charge control agent, and the fine polytetrafluoroethylene particles, whose average primary particle size is at least 0.05 .mu.m and less than 0.5 .mu.m, being externally added to the surface of the toner particle. The nonmagnetic one-component developing method includes the step of loading the above positively chargeable toner in a developer device for a nonmagnetic one-component toner.
    Type: Grant
    Filed: November 6, 1996
    Date of Patent: November 4, 1997
    Assignee: KAO Corporation
    Inventors: Shin-ichi Sata, Jun Shimizu, Masayuki Maruta
  • Patent number: 5665512
    Abstract: A mono-component toner comprises binder resin; a colorant; first charge controlling agent that has an amount of solubility between 10% and 50% by weight with respect to toluene; and a second charge control agent that includes nitrogen atom.
    Type: Grant
    Filed: November 1, 1995
    Date of Patent: September 9, 1997
    Assignee: Minolta Co., Ltd.
    Inventors: Chikara Tsutsui, Hiroyuki Fukuda, Junju Machida
  • Patent number: 5665511
    Abstract: A surface-treated inorganic fine particle includes an inorganic fine particle, a hydrophobizing agent deposited on the surface of the inorganic fine particle and an amino group-containing coupling agent deposited on the surface of the inorganic fine particle, wherein the hydrophobizing agent and the amino group-containing coupling agent in a ratio of 1/(0.01 to 0.1) by weight are deposited on the surface of the inorganic fine particle by treating the surface of the inorganic fine particle with the hydrophobizing agent and the amino group-containing coupling agent. An electrophotographic developer contains toner particles and the surface-treated inorganic fine particles.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: September 9, 1997
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Takashi Imai, Satoshi Inoue, Masanori Ichimura, Yutaka Sugizaki, Susumu Saito, Masaru Miura, Michio Take, Yasuo Yamamoto, Koji Fukushima, Manabu Serizawa
  • Patent number: 5641600
    Abstract: A magnetic toner composed of a binder resin and magnetic fine particles, wherein the magnetic fine particles are coated with an iron-zinc oxide on their surfaces and the magnetic fine particles have a saturation magnetization (.sigma.s) of 50 Am.sup.2 /kg or above under a magnetic field of 79.58 kA/m (1K oersted) where the product of residual magnetization (.sigma.r, Am.sup.2 /kg) and coercive force (Hc, kA/m), .sigma.r.times.Hc, is in the range between 60 and 250 (kA.sup.2 m/kg).
    Type: Grant
    Filed: July 31, 1995
    Date of Patent: June 24, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takaaki Kotaki, Masaki Uchiyama, Yasutaka Akashi, Makoto Unno, Yushi Mikuriya, Tadashi Dojyo
  • Patent number: 5641601
    Abstract: An electrophotographic toner suitable for use in an image-forming apparatus employing an organic photoconductor is disclosed which comprises toner particles and, adherent to the surface thereof, magnetic particles having an FeO content of 17% by weight or lower, a specific surface area of from 2.5 to 6 m.sup.2 /g, and an octahedral or hexahedral particle shape. The toner functions to prevent toner components and paper dust from adhering to the surface of an organic photoconductor, and has satisfactory moisture resistance.
    Type: Grant
    Filed: April 12, 1996
    Date of Patent: June 24, 1997
    Assignee: Tomoegawa Paper Co., Ltd.
    Inventors: Shuji Mitani, Kazuhiro Sato, Kazuhiko Mizuno, Yoshiyuki Hasegawa
  • Patent number: 5637430
    Abstract: The nonmagnetic one-component toner is usable in a developer device including a developer roller and a blade, the blade serving to regulate a toner layer formed on the developer roller into a uniform thickness and to supply electric charges to the toner by triboelectric charging, and the nonmagnetic one-component toner includes at least a binder resin, a colorant, and an iron compound. Here, the binder resin includes a polyester resin as a main component, and the iron compound has the general formula (I) and is contained in an amount of between 0.1 parts by weight or more and less than 1.0 part by weight, based on 100 parts by weight of the binder resin.
    Type: Grant
    Filed: May 29, 1996
    Date of Patent: June 10, 1997
    Assignee: Kao Corporation
    Inventors: Jun Shimizu, Shin-ichi Sata, Yasuhiro Hidaka, Masayuki Maruta
  • Patent number: 5620823
    Abstract: A developing agent for electrophotography which comprises toner particles containing a resin binder and a colorant. The toner particles include which have diameter of 5 .mu.m or less and which account for less than 10% by number of all particles, and include particles which have diameter of 20 .mu.m or more and which account for less than 0.5% by weight, and the weight average standard deviation in particle diameter of the toner particles is 2.5 .mu.m or less. The developing agent may further contain an external additive comprising small silica particles 6 nm to less than 18 nm in average primary particle diameter and large silica particles 18 nm to less than 46 nm in average primary particle diameter.
    Type: Grant
    Filed: November 1, 1995
    Date of Patent: April 15, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akira Kambayashi, Yukio Koizumi, Shigeyuki Kuroiwa
  • Patent number: 5620825
    Abstract: There are provided dry toner particles wherein the toner resin comprises more than 10% by weight of one or more polysiloxane modified resins. In this resin the polysiloxane moieties are attached to the other polymeric moieties (POL) of said copolymer over an ether group or an ester group. In a preferred embodiment the toner resin of the dry toner particles consists of one or more polysiloxane modified resins.
    Type: Grant
    Filed: March 18, 1996
    Date of Patent: April 15, 1997
    Assignee: Agfa-Gevaert, N.V.
    Inventors: Serge Tavernier, August Marien, Werner Op de Beeck
  • Patent number: 5604074
    Abstract: A developing method of the present invention has the steps of forming a uniform layer of a nonmagnetic one-component toner on a developer carrying sleeve with a developer blade; rotating an electrostatic latent image forming member and the developer carrying sleeve; and applying the toner on the developer carrying sleeve onto an electrostatic latent image formed on the electrostatic latent image forming member. The toner used herein is an encapsulated toner having a heat-fusible core material and a shell formed thereon. By using this development for a nonmagnetic one-component toner of the present invention, clear images free from background can be stably formed for a large number of copying.
    Type: Grant
    Filed: May 1, 1995
    Date of Patent: February 18, 1997
    Assignee: KAO Corporation
    Inventors: Shin-ichiro Yasuda, Kuniyasu Kawabe, Koji Akiyama, Mitsuhiro Sasaki, Koji Kameyama
  • Patent number: 5578409
    Abstract: A toner for developing an electrostatic image has a binder resin and a colorant.The binder resin contains a polyester resin at least part of which has a long-chain alkyl group having 22 to carbon atoms and has a hydroxyl group or a carboxyl group at its terminal.
    Type: Grant
    Filed: November 15, 1995
    Date of Patent: November 26, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takaaki Kotaki, Masaaki Taya, Makoto Unno, Yushi Mikuriya, Tadashi Dojyo
  • Patent number: 5547796
    Abstract: A developer for developing an electrostatic image is constituted by an insulating magnetic toner, inorganic fine powder and a flowability-improving agent having a BET specific surface area of at least 30 m.sup.2 /g. The insulating magnetic toner has a weight-average particle size (t-D.sub.4) of 4-14 .mu.m, a number-average particle size (t-D.sub.1) of 1-10 .mu.m, and a ratio (t-D.sub.4)/(t-D.sub.1) of 1.01-2. The inorganic fine powder has a weight-average particle size (m-D.sub.4) of 0.6-5 .mu.m, a number-average particle size (m-D.sub.1) of 0.5-4 .mu.m, and a ratio (m-D.sub.4)/(m-D.sub.1) which is in the range of 1.0-2.4 and is equal to or larger than the ratio (t-D.sub.4)/(t-D.sub.1). The inorganic fine powder is contained in an amount which is 2-8 times that of the flowability-improving agent by weight. The developer is able to retain stable developing performances by effecting suppressing preferential consumption of a particular particle size fraction in a long term of successive copying.
    Type: Grant
    Filed: July 18, 1994
    Date of Patent: August 20, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takaaki Kohtaki, Masaaki Taya, Masami Fujimoto
  • Patent number: 5536614
    Abstract: A nonmagnetic single-component developer is manufactured by admixing fluoropolymer fine powder to a toner containing a thermoplastic binder resin and a coloring pigment in an amount of 0.1 to 10% by weight of the resultant mixture. The fluoropolymer fine powder has a weight-average particle size smaller than that of the toner, and the amount of particles each having a size not larger than 3 .mu.m and contained in the fluoropolymer fine powder is not larger than 30% by weight. The method may be such that classifying by particle size is effected to the mixture of the toner and the fluoropolymer fine powder to remove smaller particles present therein.
    Type: Grant
    Filed: April 21, 1995
    Date of Patent: July 16, 1996
    Assignee: NEC Corporation
    Inventors: Kunio Kondo, Yujiro Fukuda
  • Patent number: 5532095
    Abstract: A magnetic toner includes at least binding resin (for instance, a styrene-acryl resin) and magnetic powder (for instance, Mn--Zn ferrite or Ni--Zn ferrite) having a saturation magnetization of at least 50 emu/g and a coercive force as measured under the magnetic field of 10 kOe not exceeding 50 Oe. An image formed by using this magnetic toner has high quality and is free of tailing.
    Type: Grant
    Filed: August 24, 1994
    Date of Patent: July 2, 1996
    Assignee: Hitachi Metals, Ltd.
    Inventors: Masumi Asanae, Masahisa Ochiai, Fumio Kimura, Akihiko Funakawa, Toshihiko Noshiro
  • Patent number: 5527657
    Abstract: A one-component magnetic toner with high resistivity for use in electrophotography for developing latent electrostatic images to visible toner images by contact development, includes a coloring agent, a binder resin, and a magnetic material which contains a bivalent metal and a trivalent iron with the molar ratio of the bivalent metal to the trivalent iron being 1/3 or less.
    Type: Grant
    Filed: November 22, 1994
    Date of Patent: June 18, 1996
    Assignee: Ricoh Company, Ltd.
    Inventors: Fuchio Takeda, Hachiro Tosaka, Kunihiko Tomita
  • Patent number: 5503954
    Abstract: A nonmagnetic one-component toner is produced by the steps of applying inorganic fine particles having an average particle diameter of not less than 30 nm and less than 100 nm to the surface of the toner having a binder resin and a colorant; and removing agglomerations of the inorganic fine particles remaining unadhered on the toner surface using a cyclone in a gas stream. The inorganic fine particles used in the present invention have a particle diameter in suitable ranges, so that the resulting toner can have suitable powder fluidity, and that these inorganic fine particles are less likely to be embedded into the inner portion of the toner by the nip pressure exerted by such members as the charging blade. Therefore, by using the toner of the present invention, a nonmagnetic one-component developing system with small variations in image density and image quality after continuous copying can be provided.
    Type: Grant
    Filed: May 4, 1994
    Date of Patent: April 2, 1996
    Assignee: Kao Corporation
    Inventors: Masayuki Maruta, Shin-ichi Sata, Yasuhiro Hidaka
  • Patent number: 5501932
    Abstract: A positive charge control agent whose active ingredient is a complex salt compound of the amine derivative represented by the following formula 1!: ##STR1## wherein X.sup.a, X.sup.1, X.sup.2 and X.sup.3 independently represent --O-- or --S--;L.sup.1 represents a divalent group selected from the group consisting of alkylene groups having 1 to 4 carbon atoms which are branched or not branched, cycloalkylene groups, and monocyclic or polycyclic arylene groups which have or do not have a substituent;A.sup.1, A.sup.2 and A.sup.3 independently represent hydrogen, an alkyl group, a cycloalkyl group, an aralkyl group, a monocyclic or polycyclic aryl group which has or does not have a substituent or a residue of a nitrogen-containing heterocyclic compound having an --OH group or an --SH group;p represents an integer from 1 to 4;q represents an integer from 0 to 20;K1.multidot.
    Type: Grant
    Filed: March 29, 1994
    Date of Patent: March 26, 1996
    Assignee: Orient Chemical Industries, Ltd.
    Inventors: Shuji Sugawara, Kazuaki Sukata, Shun-ichiro Yamanaka
  • Patent number: 5489497
    Abstract: A toner comprised of resin, magnetite treated, or coated with a phosphate titanium component, optional wax, charge additive, and surface additives comprised of silica and metal oxides.
    Type: Grant
    Filed: September 1, 1994
    Date of Patent: February 6, 1996
    Assignee: Xerox Corporation
    Inventors: Eugene F. Young, Dennis J. O'Keefe
  • Patent number: 5474869
    Abstract: A toner comprising a binder resin and a coloring agent, with an aggregation degree of 5 to 60%, and an absolute value of Q/M measured by the suction method of 2 to 30 .mu.
    Type: Grant
    Filed: September 30, 1994
    Date of Patent: December 12, 1995
    Assignee: Ricoh Company, Ltd.
    Inventors: Masami Tomita, Kohichi Katoh, Tomoe Hagiwara, Koji Suzuki, Shigekazu Enoki, Naoki Iwata, Motoi Orihara, Shinichi Kuramoto
  • Patent number: 5456990
    Abstract: A magnetic toner comprising a binder resin having dispersed therein a magnetic powder is disclosed, wherein the magnetic toner has a volume average particle diameter (D.sub.50) of from 4 to 9 .mu.m, the magnetic powder has a number average particle diameter of from 0.15 to 0.25 .mu.m (hereinafter simply referred to as a particle diameter), a BET specific surface area of from 6 to 8 m.sup.2 /g, and a residual magnetization of from 7 to 10 emu/g, the magnetic powder is present in an amount of from 30 to 70% based on the total weight of the magnetic toner, and the magnetic toner has adhered to the surface thereof silica powder having been rendered hydrophobic. The magnetic toner exhibits superior performance in terms of image density, definition, dot and fine line reproducibility, and environmental stability.
    Type: Grant
    Filed: March 17, 1994
    Date of Patent: October 10, 1995
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Seiichi Takagi, Toshiyuki Yano, Hiroe Okuyama, Teruo Masukawa, Sueko Sakai, Emi Takahashi
  • Patent number: 5437954
    Abstract: An electrophotographic toner composition comprising toner particles composed of a binder resin and a colorant and fine particles adhered to the surface of the toner particles is disclosed, in which said fine particles are zinc oxide fine particles having an average particle size of from 2 to 100 nm and having been surface-treated with a silane coupling agent or a silicone oil. The toner composition is excellent in charging properties, such as chargeability, environmental stability of chargeability, and toner admixing properties.
    Type: Grant
    Filed: February 16, 1994
    Date of Patent: August 1, 1995
    Assignee: Fuji Xerox Co., Ltd.
    Inventor: Susumu Saito
  • Patent number: 5436102
    Abstract: An apparatus develops an electrostatic latent image formed on an image carrier by attaching a developing agent containing toners, thereby converting the latent image into a toner image, transfers the toner image on a sheet, and fixes the toner image, thereby recording an image. The developing agent consists of a first magnetic toner containing less than 45 wt. % of a magnetic powder and having a comparatively low magnetism and low charge amount, and a second magnetic toner which has almost the same particle diameter as that of the first magnetic toner and charge characteristics of the same polarity as that of the first magnetic toner, contains 45 wt. % or more of a magnetic powder, and has a comparatively high magnetism and low charge amount. The first and second magnetic toners are mixed with a formulating proportion of 20 to 99 parts by weight and 1 to 80 parts by weight, respectively. The apparatus includes a convey mechanism for conveying the developing agent to the image carrier with a magnetism.
    Type: Grant
    Filed: September 10, 1993
    Date of Patent: July 25, 1995
    Assignee: Olympus Optical Co., Ltd.
    Inventors: Shunichi Kubo, Masao Shionoya
  • Patent number: 5413892
    Abstract: An electrostatic image developing toner containing a compound of the following formula (1): ##STR1## wherein X is ##STR2## (wherein D is a hydrogen atom or an electron donating group, and each of R.sub.1 and R.sub.2 which are independent of each other, is a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an aryl group, an aralkyl group, a hydroxyl group, an amino group, a dialkylamino group, a diarylamino group, a diaralkylamino group, a halogen atom, a halogen-substituted alkyl group, a halogen-substituted aryl group, a cyano group, a formyl group, a carboxyl group, a carbamoyl group, an N-substituted carbamoyl group, an alkoxycarbonyl group, an acyloxy group, an acyl group, an arylcarbonyl group, a nitro group, a sulfonic acid group, an alkylsulfonyl group, a substituted sulfonyl group, a sulfamoyl group, an N-substituted sulfamoyl group or a substituted sulfinyl group, provided that when D is a hydrogen atom, R.sub.1 and R.sub.
    Type: Grant
    Filed: May 18, 1994
    Date of Patent: May 9, 1995
    Assignee: Hodogaya Chemical Co., Ltd.
    Inventors: Yuji Matsuura, Osamu Mukudai, Mitsutoshi Anzai, Kayoko Watanabe
  • Patent number: 5413891
    Abstract: An electrophotographic toner containing a compound of the following formula (1): ##STR1## wherein X is awherein A is an electron attractive group, and each of R.sub.1 and R.sub.2 which are independent of each other, is a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an aryl group, an aralkyl group or a hydroxyl group, or R.sub.1 and R.sub.2 together form a ring), ##STR2## wherein A, R.sub.1 and R.sub.2 are as defined above), or ##STR3## wherein A, R.sub.1 and R.sub.2 are as defined above), and Y is a hydrogen atom, an alkyl group or an aryl group.
    Type: Grant
    Filed: April 13, 1994
    Date of Patent: May 9, 1995
    Assignee: Hodogaya Chemical Co., Ltd.
    Inventors: Yuji Matsuura, Osamu Mukudai, Mitsutoshi Anzai, Kayoko Watanabe
  • Patent number: 5407769
    Abstract: A method of recording an image, comprises the steps of;(a) bringing a magnetic developer into support on a developer-holding member having therein a magnetic-field generation means; the magnetic developer comprising toner particles containing an organic magnetic resin capable of being softened by heating and heat-curable at a temperature higher than its softening temperature;(b) transporting the magnetic developer to a developing area of a latent image holding member disposed opposingly to said developer-holding member;(c) developing a latent image to form a toner image;(d) transferring the toner image to a recording paper; and(e) heating the transferred toner image to a temperature higher than the softening temperature of the organic magnetic resin so that the toner image is fixed to the recording paper.
    Type: Grant
    Filed: November 26, 1993
    Date of Patent: April 18, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventor: Nagao Hosono
  • Patent number: 5397670
    Abstract: A non-magnetic one-component toner developer for use in electrophotographic processes having a particle size distribution represented by the following expressions: d.sub.1 /d.sub.50 =0.32.about.0.55; d.sub.50 /d.sub.90 =0.50.about.0.70; and d.sub.50 =5-15.mu., wherein d.sub.1, d.sub.50, and d.sub.90 represent diameters of toner particles when the percentiles by volume or by weight of toner developer of that diameter are 1%, 50%, and 90%, respectively. The non-magnetic one-component toner developer disclosed in the present invention has a triboelectricity greater than 1.5 .mu.C/g, a bulk specific gravity than 0.36, and a compression ratio less than 0.24, and exhibits excellent triboelectrification characteristics and flowability, as well as provides uniformly clear images without foggy background.
    Type: Grant
    Filed: July 13, 1993
    Date of Patent: March 14, 1995
    Assignee: Industrial Technology Research Institute
    Inventors: Hun-Yi Tong, Yeong-Sheng Lin