Identified Adjuvant, I.e., Surfactant, Etc. Patents (Class 430/115)
  • Patent number: 4925766
    Abstract: Liquid toners for developing electrophotographic images contain dispersed toner particles which are based on a polymer with multi-characteristics. These particles comprise a thermoplastic resinous core with a T.sub.g below room temperature, which is chemically anchored to an amphipathic copolymer steric stabilizer containing covalently attached groups of a coordinating compound which in turn are capable of forming covalent links with organo-metallic charge directing compounds. The toner particles so formed have advantageous properties of high charge/mass, and good charge and dispersion stability.
    Type: Grant
    Filed: December 2, 1988
    Date of Patent: May 15, 1990
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Mohamed A. Elmasry, Kevin M. Kidnie
  • Patent number: 4923778
    Abstract: Process for preparation of toner particles for electrostatic liquid developers utilizing a single vessel wherein (A) a thermoplastic resin and hydrocarbon liquid having a Kauri-butanol value of less than 120 at a total of solids of at least 22% by weight are dispersed in the vessel by moving particulate media (crating shear) at elevated temperature to plasticize and liquify the resin, (B) while the particulate media are maintained in continuous motion the dispersion is cooled whereby the resin precipitates in the form of toner particle having an average by area particle size of 10 .mu.m or less, and (C) the particulate media are removed. Liquid electrostatic developers are prepared by the addition of a charge director compound. The liquid developers are prepared in a shorter time that previously known processes. The liquid developers are useful for preparation of copies and proofs of various colors.
    Type: Grant
    Filed: December 23, 1988
    Date of Patent: May 8, 1990
    Assignee: D X Imaging
    Inventors: David E. Blair, Bradley J. Gollhardt, James R. Larson
  • Patent number: 4917985
    Abstract: Positive electrostatic liquid developer consisting essentially of(A) nonpolar liquid having Kauri-butanol value less than 30, present in major amount,(B) thermoplastic resin particles having an organic sulfur-containing compound which is substantially insoluble in the nonpolar liquid at ambient temperatures, as defined dispersed therein and average particle size by area being less than 10 .mu.m, and(C) nonpolar liquid soluble ionic or zwitterionic charge director compound. Optionally a colorant and charge adjuvant are present. The electrostatic liquid developer is useful in copying, making proofs including digital color proofs, lithographic printing plates, and resists.
    Type: Grant
    Filed: December 30, 1988
    Date of Patent: April 17, 1990
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Lyla M. El-Sayed, Torence J. Trout
  • Patent number: 4917986
    Abstract: A positive, liquid electrostatic developer consisting essentially of(A) a nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount,(B) thermoplastic resin particles having dispersed therein a phosphorous-containing compound defined herein which is substantially insoluble or immiscible in the nonpolar liquid at ambient temperatures, the resin particles having an average by area particle size of less than 10 .mu.m, and(C) a nonpolar liquid soluble ionic or zwitterionic charge director compound, and process for preparation. The liquid developer is useful in copying, color proofing including digital color proofing, lithographic printing plates and resists.
    Type: Grant
    Filed: December 30, 1988
    Date of Patent: April 17, 1990
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Dominic M. T. Chan, Torence J. Trout
  • Patent number: 4898802
    Abstract: A negatively charged toner composition comprised of resin particles, pigment particles, and as a charge enhancing additive certain salts of 5,5'-spirobi(5H-dibenzoborole).
    Type: Grant
    Filed: May 22, 1989
    Date of Patent: February 6, 1990
    Assignee: Xerox Corporation
    Inventors: Bing R. Hsieh, Robert J. Gruber, John L. Haack
  • Patent number: 4897332
    Abstract: Improved charge control agent for electrophotographic liquid toners comprising a mixture of lecithin and an alkylated poly-N-vinyl pyrrolidone polymer is disclosed. Methods include applying liquid toners comprising such charge control agent mixture to an electroconductive substrate that has been electrostatically charged in the image areas thereof.
    Type: Grant
    Filed: October 5, 1988
    Date of Patent: January 30, 1990
    Assignee: AM International, Inc.
    Inventors: George A. Gibson, Ray H. Luebbe, Jr.
  • Patent number: 4891286
    Abstract: Methods of using improved liquid toner dispersions in high-speed electrophotography are disclosed wherein pigment charge homogeneity and mobility are improved by the addition of effective carrier liquid-insoluble monomeric organic acids to the toner solution. Preferred acids include benzoic, succinic, p-toluenesulfonic acid, phenylphosphonic acid, salicylic acid, and 2-nitro and 4-nitrobenzoic acid.
    Type: Grant
    Filed: November 21, 1988
    Date of Patent: January 2, 1990
    Assignee: AM International, Inc.
    Inventor: George A. Gibson
  • Patent number: 4886730
    Abstract: A life of a starting liquid developer for electrostatic photography is prolonged by using a supplemental developer that returns an electrically charged state of the developer varied by repeated use of the developer to an original or appropriate state of the electrical charge for electrostatic photography.
    Type: Grant
    Filed: July 11, 1988
    Date of Patent: December 12, 1989
    Assignee: Iwatsu Electric Co., Ltd.
    Inventors: Ikuo Oto, Hayato Hyakutake, Ryo Kobirumaki
  • Patent number: 4886729
    Abstract: A positively charged liquid developer composition comprised of polymer particles, a hydrocarbon liquid component, a charge director comprised of lecithin, and as pigment particles the beta crystalline form of copper phthalocyanine.
    Type: Grant
    Filed: July 15, 1988
    Date of Patent: December 12, 1989
    Assignee: Xerox Corporation
    Inventors: Bernard Grushkin, David E. Hutka, Louis V. Isganitis, Edward J. Radigan
  • Patent number: 4886726
    Abstract: Electrostatic liquid developer consisting essentially of(A) nonpolar liquid having Kauri-butanol value less than 30, present in major amount,(B) at least one thermoplastic resin having an average particle size by area of less than 10 .mu.m, and(C) at least one glyceride charge director as defined. Optionally a colorant and a charge adjuvant can be present. The elastrostatic liquid developer is useful in copying, making proofs, including digital color proofs, lithographic printing plates, resists and medical hardcopies.
    Type: Grant
    Filed: November 25, 1987
    Date of Patent: December 12, 1989
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Dominic M. Chan, Lyla M. El-Sayed, Chandrakant B. Thanawalla, Torence J. Trout
  • Patent number: 4880720
    Abstract: Disclosed is an electrophotographic liquid developer composition comprising a liquid medium, first toner particles charged to one polarity and comprising a resin and a first pigment, second toner particles charged to a polarity opposite to that of the first toner particles and comprising a resin and a second pigment of a color different from that of the first pigment, and a charge director. The disclosed developer is suitable for developing electrostatic latent images in two different colors in a single development step. The latent image comprises three areas of charge; toner particles of one color are selectively attracted to one area, toner particles of the other color are selectively attracted to the second area, and the third area remains undeveloped as a background area.
    Type: Grant
    Filed: May 23, 1988
    Date of Patent: November 14, 1989
    Assignee: Xerox Corporation
    Inventors: Stephan Drappel, Raymond W. Wong, Melvin D. Croucher
  • Patent number: 4880432
    Abstract: Disclosed is a process for preparing particles colored with a dye which comprises: (a) forming, by a free radical dispersion polymerization process in a nonaqueous solution, polymeric particles having attached thereto stabilizing copolymers with at least one functional group capable of undergoing a chemical reaction with a dye, the particles having an average diameter of from about 0.1 to about 20 microns; (b) adding a dye to the polymeric particles having attached thereto stabilizing copolymers; and (c) effecting a chemical reaction between the dye and the stabilizing copolymers that results in the dye becoming covalently bound to the polymeric particles. Also disclosed is a liquid electrophotographic developer composition comprising a liquid medium, a charge control agent, and colored polymeric toner particles prepared as stated above and having an average diameter of from about 0.5 to about 5 microns.
    Type: Grant
    Filed: January 11, 1988
    Date of Patent: November 14, 1989
    Assignee: Xerox Corporation
    Inventors: Luke S. Egan, Mitchell A. Winnik, Francoise M. Winnik
  • Patent number: 4877698
    Abstract: A process for generating two-color images comprising: (1) charging an imaging member in an imaging apparatus; (2) creating on the member a latent image comprising areas of high, intermediate, and low potential; (3) providing an electrode having a potential within about 100 volts of that of the intermediate potential, enabling generation of an electric field and a developement zone between the imaging member and the electrode; and (4) developing the latent image by introducing into the development zone a liquid developer composition containing first toner particles of one color and second toner particles of another color, the particles being dispersed in a liquid medium, wherein the second toner particles are attached to the high potential and the first toner particles are attracted to the low potential.
    Type: Grant
    Filed: May 23, 1988
    Date of Patent: October 31, 1989
    Assignee: Xerox Corporation
    Inventors: P. Keith Watson, Ian D. Morrison, Melvin D. Croucher
  • Patent number: 4874683
    Abstract: Disclosed is a liquid developer for electrophotography wherein the dispersed toner particles have a single peak distribution and the number of particles that are less than 0.06 .mu.m is not greater than 5%, and not more than 3% of the particles are greater than 1.5 .mu.m.
    Type: Grant
    Filed: September 6, 1988
    Date of Patent: October 17, 1989
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Miyuki Shirai, Akira Nogami
  • Patent number: 4869991
    Abstract: A charge director composition dispersed in at least one solvent comprising:A. a salt mixture comprised of 1-10 parts by weight each of:(i) a chromium salt of a C.sub.14-18 alkyl salicylic acid;(ii) a calcium didecyl sulfosuccinate; and(iii) a salt of the didecyl ester of sulfosuccinate acid and at least 50% of the basic nitrogen radicals of a copolymer of lauryl methacrylate, stearyl methacrylate and 2-methyl-5-vinyl pyridine, said copolymer having a vinyl pyridine content of 20-30% by weight and an average molecular weight of 15,000-250,000; andB. a salt-free copolymer of (i) laurylmethacrylate and (ii) a monomer selected from 2- or 4-vinylpyridine, styrene and N,N-dimethylaminoethylmethacrylate and mixtures thereof, said copolymer having a molecular weight from about 15,000 to about 100,000, and the weight ratio of monomers B(i) to B(ii) is from about 4:1 to about 50:1; and wherein the weight ratio of B:A is from 10:3 to about 40:3.
    Type: Grant
    Filed: October 3, 1988
    Date of Patent: September 26, 1989
    Assignee: Olin Hunt Specialty Products Inc.
    Inventors: Joseph deGraft-Johnson, Chi Ma, Richard R. L. Wells
  • Patent number: 4868084
    Abstract: A developer for developing electrostatic latent images comprises negatively chargeable toner particles and hydrophobic, negatively chargeable silica fine power,said silica fine powder being obtained by treating silica fine powder with a silane coupling agent represented by the following formula:RmSiYn or Y.sub.3 --Si--NH--Si--Y.sub.3and treating further said treated silica fine powder with a silicone oil having the structure: ##STR1## An image forming method comprises forming an electrostatic latent image on a photosensitive drum; developing said latent image with a developer to form toner images, said developer comprising negatively chargeable toner particles and, hydrophobic, negatively chargeable silica fine powder,said silica fine powder being obtained by treating silica fine powder with a silane coupling agent represented by the following formula:RmSiYn or Y.sub.3 --Si--NH--Si--Y.sub.
    Type: Grant
    Filed: December 1, 1987
    Date of Patent: September 19, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hitoshi Uchide, Tetsuya Kuribayashi, Manabu Ohno
  • Patent number: 4860050
    Abstract: A developing replenisher material or a replenisher liquid developer to be supplied to a developer tank of an electrostatic copying machine comprises 1000 parts by weight of a carrier liquid composed mainly of aliphatic hydrocarbon and 200 or 1200 parts by weight of toner particles composed mainly of a binder resin and a pigment. The toner concentration of the replenisher liquid developer is high enough to prevent an overflow from the developer tank, allow many copies to be produced by the copying machine, and prevent a solvent shock. The toner particles, when added to the carrier liquid, can immediately and well be dispersed in the carrier liquid.
    Type: Grant
    Filed: July 28, 1987
    Date of Patent: August 22, 1989
    Assignee: Ricoh Company, Ltd.
    Inventors: Tsuneo Kurotori, Manabu Mochizuki, Kenzo Ariyama, Shinichi Kuramoto, Yoshihiro Sugiyama, Hajime Takanashi, Takashi Ishizuka, Yoshio Kudo, Yoshio Sato
  • Patent number: 4859559
    Abstract: Negative, liquid electrostatic developer consisting essentially of(A) nonpolar liquid having Kauri-butanol value less than 30, present in major amount. `(B) thermoplastic resin particles having a hydroxycarboxylic acid as defined dispersed therein and average particle size by area being less than 10 .mu.m, and(C) nonpolar liquid soluble ionic or zwitterionic compound which imparts a negative charge to the thermoplastic resin particles. Optionally additional adjuvants are present. The liquid electrostatic developer is useful in copying, making proofs including digital color proofs, lithographic printing plates, and resists.
    Type: Grant
    Filed: March 18, 1987
    Date of Patent: August 22, 1989
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Torence J. Trout
  • Patent number: 4855396
    Abstract: New polyesters are provided, having advantageous utility as dual function binder/charge agents in electrostatographic toner particles. The new polyesters contain a quaternary phosphonium salt comprising a cationic portion and an anionic portion, wherein the cationic portion comprises a phosphonium atom directly covalently bonded to at least one aryl moiety substituted with a group containing an ester linkage to the rest of the polyester, and wherein the anionic portion of the salt comprises an arylsulfonate moiety in which the aryl group is unsubstituted or is substituted with one or more alkyl, halide, or group having an ester linkage to the rest of the polyester.
    Type: Grant
    Filed: August 5, 1988
    Date of Patent: August 8, 1989
    Assignee: Eastman Kodak Company
    Inventors: John C. Wilson, Thomas A. Jadwin
  • Patent number: 4851316
    Abstract: A positively charged liquid toner composition comprised of a liquid carrier vehicle component, binder resin particles, pigment particles; and a charge enhancing additive comprised of a lake complex obtained by the reaction of an amino acid and a polyvalent metal.
    Type: Grant
    Filed: December 24, 1987
    Date of Patent: July 25, 1989
    Assignee: Xerox Corporation
    Inventors: Chin H. Lu, Joseph S. Chow
  • Patent number: 4840865
    Abstract: A liquid developer for electrostatic photography is disclosed, comprising a non-aqueous solvent having electrical resistivity of not less than 10.sup.9 .OMEGA..cm and a dielectric constant of not more than 3.5 having dispersed therein at least a resin, wherein said resin is a copolymer resin obtained by subjecting a solution containing (A) at least one of monofunctional monomer which is soluble in said solvent but insolubilized upon polymerization and (B) at least one of monomers having at least two polar groups and/or polar linking groups represented by formula (I): ##STR1## wherein V, Y, R.sub.1, R.sub.2, X.sub.1, X.sub.2, a.sub.1, and a.sub.2 are defined in the specification, to a polymerization reaction in the presence of a resin which is soluble in said solvent and contains no graft group polymerizable with said monomers.
    Type: Grant
    Filed: December 29, 1986
    Date of Patent: June 20, 1989
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Eiichi Kato, Shigeyuki Dan, Hiroshi Ishibashi, Kazuo Ishii, Hidefuji Sera
  • Patent number: 4837102
    Abstract: A liquid developer for electrostatic photography comprising a carrier medium having an electrical resistivity of not less than 10.sup.9 106.cm and a dielectric constant of not more than 3.5 having dispersed therein at least a resin, wherein said resin is a copolymer resin obtained by copolymerizing (1) a solution containing at least one copolymer having an unsaturated bond obtained by copolymerizing at least one monomer (A) represented by formula (I) shown below and at least one monomer (B) represented by formula (II) shown below, and reacting the resulting copolymer with at least one monomer (C) represented by formula (III) shown below, (2) at least one monomer (D) which is soluble in the carrier medium but becomes insoluble upon polymerization, and (3) at least one monomer (E) represented by formula (IV) shown below to obtained a resin dispersion: ##STR1## wherein a.sub.1, a.sub.2 a.sub.3, b.sub.1, b.sub.2, b.sub.3, d.sub.1, d.sub.2, d.sub.3, e.sub.1, e.sub.2, e.sub.3, X, Y, V, Z, L, F, Q, G, R.sub.1, R.
    Type: Grant
    Filed: September 9, 1987
    Date of Patent: June 6, 1989
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shigeyuki Dan, Eiichi Kato, Kazuo Ishii, Hiroshi Ishibashi, Hidefumi Sera
  • Patent number: 4837103
    Abstract: This invention provides a negative-charging liquid developer for electrostatic photography excellent in charge stability and dispersion stability which comprises a highly insulating carrier liquid in which resin particles containing a charge control agent are dispersed, said charge control agent being a carboxylic acid amine salt which comprises a polycarboxylic acid compound insoluble in said carrier liquid and a high molecular amino compound soluble in said carrier liquid.
    Type: Grant
    Filed: November 12, 1987
    Date of Patent: June 6, 1989
    Assignee: Mitsubishi Paper Mills, Ltd.
    Inventors: Hirokazu Yamamoto, Akira Furukawa
  • Patent number: 4830945
    Abstract: Disclosed is an electrophotographic liquid developer composition comprising a liquid medium, first toner particles charged to one polarity and comprising a first dye and polymeric cores to which steric stabilizer polymers have been attached, second toner particles charged to a polarity opposite to that of the first toner particles and comprising a second dye of a different color than the first dye and polymeric cores to which steric stabilizer polymers have been attached, and a charge director. The disclosed developer is suitable for developing electrostatic latent images in two different colors in a single development step. The latent image comprises three areas of charge, toner particles of one color are selectively attracted to one area, toner particles of the other color are selectively attracted to the second area, and the third area remains undeveloped as a background area.
    Type: Grant
    Filed: May 23, 1988
    Date of Patent: May 16, 1989
    Assignee: Xerox Corporation
    Inventors: Raymond W. Wong, Stephan Drappel, Melvin D. Croucher
  • Patent number: 4822710
    Abstract: Disclosed is an improved liquid developer composition comprised of an oil base comprised of Magiesol, pigment particles, a dispersant, and a thickener component.
    Type: Grant
    Filed: February 20, 1987
    Date of Patent: April 18, 1989
    Assignee: Xerox Corporation
    Inventors: Melvin D. Croucher, James M. Duff, John R. C. Fuler, George R. Pravato, Raymond W. Wong
  • Patent number: 4820605
    Abstract: Liquid Electrostatic Developer consisting essentially ofA. nonpolar liquid having a Kauri-butanol value of less than 30, present in major amount,B. at least one thermoplastic resin having average by area particle size of less than 10 .mu.m,C. a charge director compound,D. particles of a blend of wax and at least one metallic soap or inorganic metal salt, e.g., triglyceride wax/metallic soap or metal salt.Optionally a colorant is present. The liquid electrostatic developer is useful in copying, e.g., medical hard copies, making proofs, lithographic printing plates, and resists.
    Type: Grant
    Filed: November 25, 1987
    Date of Patent: April 11, 1989
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Lyla M. El-Sayed
  • Patent number: 4816370
    Abstract: A liquid developer composition comprised of an oil base, dyed polymer particles, charge control additives, and stabilizers that enable the flocculation of the composition, which stabilizers possess a solubility temperature equal to or exceeding 40.degree. C.
    Type: Grant
    Filed: August 24, 1987
    Date of Patent: March 28, 1989
    Assignee: Xerox Corporation
    Inventors: Melvin D. Croucher, Raymond W. Wong, Michael L. Hair
  • Patent number: 4814251
    Abstract: Disclosed is a xeroradiographic liquid developer composition comprising an isoparaffinic hydrocarbon, a pigment, a first polymeric resin component comprising a vinyl toluene acrylic terpolymer resin, and a second polymeric resin component comprising an acrylic copolymer resin.
    Type: Grant
    Filed: October 29, 1987
    Date of Patent: March 21, 1989
    Assignee: Xerox Corporation
    Inventor: Steven E. Igoe
  • Patent number: 4812377
    Abstract: Dry or liquid developers capable of forming high resolution electrostatographic images are made from finely divided toner particles comprising a fusible branched chain, polyester resin which contains 2,3-dihydro,1,3-dioxo-2-yl-1H-isoindole-ar(-yl or -diyl) groups derived, for example, from a 2,3-dihydro-1,3-dioxo-1H-isoindole-5-carboxylic acid. The toner compositions are brittle and can be ground to very small particle size for high resolution image development; they have good cohesivity and resist toner offset; they are fusible at low temperatures; and, in preferred embodiments, are capable of forming transparent color images.
    Type: Grant
    Filed: March 28, 1988
    Date of Patent: March 14, 1989
    Assignee: Eastman Kodak Company
    Inventors: John C. Wilson, Domenic Santilli, Lawrence P. DeMejo
  • Patent number: 4798778
    Abstract: A positive-working liquid electrostatic developer consisting essentially of(A) nonpolar liquid having a Kauri-butanol value of less than 30, present in major amount;(B) thermoplastic resin of an ethylene homopolymer or copolymer of ethylene and at least one other monomer, the resin having as a substituent thereon an ester, ester having substitutents, e.g., hydroxyl, carboxyl, amine, alkyl; an amide, amide having substituents, e.g., hydroxyl, carboxyl, amine, alkyl; or acid halide of a carboxylic acid, the resin being in particulate form having an average particle size by area of less than 10 .mu.m; and(C) nonpolar liquid soluble ionic or zwitterionic compound.Several procedures can be used to prepare the developer, e.g., using toner concentrate, modifying a thermoplastic resin before developer is prepared. Pigments and adjuvants can be present in the developer which is useful in copying, making proofs including digital proofs, lithographic printing plates and resists.
    Type: Grant
    Filed: August 3, 1987
    Date of Patent: January 17, 1989
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: El-Sayed Lyla M., Steven P. Schmidt, Torence J. Trout, Robert D. Mitchell
  • Patent number: 4797341
    Abstract: This invention relates to a liquid developer for electrophotography comprising toner particles dispersed in a highly insulative aliphatic hydrocarbon and/or halogenated hydrocarbon carrier liquid having a low dielectric constant, said toner particles having two particle size distributions of a mean small particle size in the range of 0.01 .mu.m to 1 .mu.m and a mean large particle size in the range of 2 .mu.m to 30 .mu.m, characterized in that said large toner particles in the range of 2 .mu.m to 30 .mu.m are prepared by using polytetrafluoroethylene as the main binder resin.
    Type: Grant
    Filed: September 4, 1986
    Date of Patent: January 10, 1989
    Assignee: Ricoh Co., Ltd.
    Inventor: Kazuo Tsubuko
  • Patent number: 4797342
    Abstract: A process for the preparation of liquid developer compositions which comprises mixing a resin with a low vapor pressure oil at elevated temperatures permitting the resin to melt and enabling the formation of a resin oil mixture; thereafter adding to the oil resin mixture at elevated temperatures pigment particles, and stirring until the pigment has become dispersed in the resin; followed by attriting the mixture while cooling, for example, to ambient temperatures; thereafter filtering the aforementioned mixture, and dispersing the product in a low viscosity oil; and subsequently adding to the formed mixture a charge control additive.
    Type: Grant
    Filed: November 23, 1987
    Date of Patent: January 10, 1989
    Assignee: Xerox Corporation
    Inventors: Melvin D. Croucher, Raymond W. Wong, Stephan Drappel
  • Patent number: 4785327
    Abstract: The disclosure is directed to liquid electrophotographic copying equipment and more particularly to an apparatus to dispense a liquid charge director composition to a reservoir that contains a liquid developer composition. Generally, the apparatus comprises a charge director reservoir including a pressure cell arranged below the liquid level of the charge director reservoir. The pressure cell has a volume to contain a predetermined amount of liquid charge director composition. The pressure cell is provided with an opening to permit a flow of liquid charge director composition from the charge director reservoir and into the interior of the pressure cell and vice versa. A tubular conduit extends from the interior of the pressure cell to the reservoir that contains the liquid developer composition to provide fluid communication therebetween.
    Type: Grant
    Filed: September 3, 1987
    Date of Patent: November 15, 1988
    Assignee: Savin Corporation
    Inventors: Benzion Landa, Haim Hochman, Yehuda Niv
  • Patent number: 4783388
    Abstract: Negative-working electrostatic liquid developer having improved charging characteristics consisting essentially of(A) nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount,(B) thermoplastic resin particles having an average by area particle size of less than 10 .mu.m,(C) nonpolar liquid soluble ionic or zwitterionic compound, and(D) a quaternaryammonium hydroxide compound as defined, e.g., tetraethylammonium hydroxide, tetrabutylammonium hydroxide, etc., soluble in an amount of at least 0.5 part per million by weight in the nonpolar liquid.The electrostatic liquid developer is useful in copying, making proofs including digital color proofs, lithographic printing plates, and resists.
    Type: Grant
    Filed: June 17, 1987
    Date of Patent: November 8, 1988
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Lyla M. El-Sayed, James R. Larson
  • Patent number: 4780389
    Abstract: Negative, liquid electrostatic developer consisting essentially of(A) nonpolar liquid having Kauri-butanol value less than 30, present in major amount,(B) thermoplastic resin particles having a colorant and an inorganic metal salt as defined dispersed therein and average particle size by area being less than 10 .mu.m, and(C) nonpolar liquid soluble ionic or zwitterionic compound which imparts a negative charge to the thermoplastic resin particles. Optionally additional adjuvants are present. The liquid electrostatic developer is useful in copying, making proofs including digital color proofs, lithographic printing plates, and resists.
    Type: Grant
    Filed: February 23, 1988
    Date of Patent: October 25, 1988
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Lyla M. El-Sayed
  • Patent number: 4780388
    Abstract: Electrostatic liquid developer having improved charging characteristics consisting essentially of(A) nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount,(B) thermoplastic resin particles having an average by area particle size of less than 10 .mu.m,(C) nonpolar liquid soluble ionic compound, and(D) at least one organic polyamine compound having at least 2 amino groups present on adjacent carbon atoms.Optionally, a colorant, e.g., a pigment; metallic soap can be present. The electrostatic liquid developer is useful in copying, making proofs including digital color proofs, lithographic printing plates, and resists.
    Type: Grant
    Filed: May 26, 1987
    Date of Patent: October 25, 1988
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: James R. Larson
  • Patent number: 4772528
    Abstract: A liquid electrostatic developer containing negatively chargeable resin particles with improved charging characteristics, said developer consisting essentially of(A) nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount;(B) resin particles of a blend of at least two polymers, at least one polymer containing at least one acidic constituent having a pKa of less than 4.5 measured at 25.degree. C. in water, and the blend having an acid number of at least one due to said acidic constitutent; the resin particles having an average by area particle size of less than 10 .mu.m, and(C) nonpolar liquid soluble ionic or zwitterionic charge director compound.A preferred polymer blend is composed of polystyrene and a sulfonated polymer, e.g., poly(2-acrylamido-2-methyl-1-propanesulfonic acid). The average resin particle size by area is less than 10 .mu.m. Optionally a colorant and other additives or adjuvants are present.
    Type: Grant
    Filed: May 6, 1987
    Date of Patent: September 20, 1988
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: James R. Larson, Torence J. Trout
  • Patent number: 4767688
    Abstract: A method for controlling charging of toner particles and/or charge-imparting materials used in electrophotography is disclosed, which comprises using as a charge-exchange control agent an organic boron compound composed of a boron-containing organic anion component and a cation component. A color developer containing the charge-exchange control agent is also disclosed, which is free from variation of tone and reduction of transparency due to the addition of the charge-exchange control agent.
    Type: Grant
    Filed: March 9, 1987
    Date of Patent: August 30, 1988
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Ken Hashimoto, Masayuki Maruta, Hidehiko Soyama, Yukihiro Ishii
  • Patent number: 4766049
    Abstract: Disclosed is a colored liquid developer composition comprised of an insulating oil base, a stabilized polymer latex component with imbibed molecularly dispersed colored dye components, and a thickener compatible with the stabilizer selected for the latex.
    Type: Grant
    Filed: January 9, 1987
    Date of Patent: August 23, 1988
    Assignee: Xerox Corporation
    Inventors: Melvin D. Croucher, Raymond W. Wong, James M. Duff, Michael L. Hair, John R. C. Fuller
  • Patent number: 4764447
    Abstract: This invention relates to a non-aqueous type resin dispersion obtained by polymerizing a polymerizable composition containing at least monomer A represented by the general formula (I), ##STR1## (wherein, R.sup.1 represents --H or --CH.sub.3, X represents --COOC.sub.n H.sub.2n+1 or --OCOC.sub.n H.sub.2n+1, and n represents an integer of 6-20), monomer B represented by the general formula (II), ##STR2## (wherein, R.sup.2 and R.sup.3 represent --H or --CH.sub.3 and m represents an integer of 1-20), and monomer C having a carboxyl group or a glycidyl group in the presence of a polymerization initiator in an aliphatic hydrocarbon solvent.
    Type: Grant
    Filed: July 8, 1986
    Date of Patent: August 16, 1988
    Assignee: Ricoh Co., Ltd.
    Inventors: Kazuo Tsubuko, Shinichi Kuramoto, Kayoko Nagai, Makoto Okawara, Hajime Takanashi
  • Patent number: 4764446
    Abstract: Disclosed is a liquid developer composition comprised of an oil base selected from the group consisting of Magiesol and Isopar, pigment particles, a stabilizer, and a surfactant that enables flocculation of the developer components, and efficient wetting of the photoreceptor surface.
    Type: Grant
    Filed: February 12, 1987
    Date of Patent: August 16, 1988
    Assignee: Xerox Corporation
    Inventors: Melvin D. Croucher, George R. Pravato, John R. C. Fuller, James M. Duff
  • Patent number: 4762764
    Abstract: A stable colored liquid developer comprising an insulating organic liquid dispersion medium having dispersed therein negatively charged marking particles comprising a thermoplastic resin core substantially insoluble in the dispersion medium, an amphipathic copolymeric steric stabilizer irreversibly anchored to the thermoplastic resin core, the steric stabilizer being soluble in the dispersion medium, a colored dye imbibed in the thermoplastic resin core, the dye being soluble in the thermoplastic resin core and insoluble in the dispersion medium and a charge control agent selected from the group consisting of a polybutene succinimide, lecithin, basic barium petroleum sulfonates, and mixtures thereof. This liquid developer may be employed to develop electrostatic latent images either on dielectric paper or on an electroreceptor or photoreceptor substrate and the resulting toner image may be transferred to another surface by tape transfer.
    Type: Grant
    Filed: December 23, 1986
    Date of Patent: August 9, 1988
    Assignee: Xerox Corporation
    Inventors: Dominic S. Ng, Raymond W. Wong, Melvin D. Croucher
  • Patent number: 4756986
    Abstract: An electrophotographic liquid toner composition having lower saturation density and method of reducing the saturation density comprising a toner particle formed from a resin, a solid pigment, and a transparent filler, said pigment and said transparent filler having similar surface energies such that they impart similar triboelectric charging properties to said composition, and said composition is further characterized in that the triboelectric properties of said composition are substantially equivalent to the triboelectric properties of a reference composition in which said filler is not present and in which the combined amount of said pigment is equal to the amount of pigment in said reference composition, and in that said transparent filler lowers the saturation density of said composition so that the saturation density of said composition is lower than the saturation density of said reference composition.
    Type: Grant
    Filed: September 3, 1986
    Date of Patent: July 12, 1988
    Assignee: Savin Corporation
    Inventor: George A. Gibson
  • Patent number: 4737432
    Abstract: A positively chargeable toner for developing electrostatic images in electrophotography, electrostatic recording, electrostatic printing, etc. The toner contains a binder resin, a colorant or magnetic material, and a diorganotin borate. Because of the diorganotin borate contained, the toner has a uniform and stable triboelectric chargeability. The improved properties of the toner are enhanced when it is combined with positively chargeable fine silica powder.
    Type: Grant
    Filed: September 15, 1986
    Date of Patent: April 12, 1988
    Assignee: Canon Kabushiki Kaisha
    Inventors: Katsuhiko Tanaka, Hirohide Tanikawa, Naoto Kitamori, Tsutomu Kukimoto, Masaki Uchiyama, Yasuo Mitsuhashi
  • Patent number: 4734352
    Abstract: Electrostatic liquid developer having improved charging characteristics consisting essentially of(A) nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount,(B) thermoplastic resin particles having an average by area particle size of less than 10 .mu.m.(C) nonpolar liquid soluble ionic or zwitterionic compound, and(D) a polyhydroxy compound, preferably soluble in the developer in an amount of at least 2% by weight.The electrostatic liquid developers are useful in copying making proofs including digital color proofs, lithographic printing plates, and resists.
    Type: Grant
    Filed: April 22, 1986
    Date of Patent: March 29, 1988
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Robert D. Mitchell
  • Patent number: 4719164
    Abstract: Improved electrostatographic suspension developers contain a pigment coated with polycyanoacrylate.Wherein the polycyanoacrylate comprises an inner shell on a pigment dispersed in an electrically insulating carrier liquid having a volume resistance of at least 10.sup.9 ohm.cm and a dielectric constant below 3 and the pigment has an additional shell of a copolymer ofA. cationic monomers which contain ammonium, phosphonium or sulfonium groups and of which the anions are derived from CH-acid compounds containing at least one C.sub.6 -C.sub.24 hydrocarbon radical andB. radically polymerizable olefinically unsaturated compounds as comonomers.
    Type: Grant
    Filed: April 14, 1986
    Date of Patent: January 12, 1988
    Assignee: Agfa Gevaert Aktiengesellschaft
    Inventors: Wolfgang Podszun, Helmut Waniczek, John Goossens
  • Patent number: 4719165
    Abstract: The present invention provides a process for preparation of a charge-regulatory agent characterized by reacting an amino acid with a titanium compound in an organic solvent to form a reaction mixture and further reacting the resultant reaction mixture with water which is equimolar or more to said titanium compound, and a liquid developer for development of an electrostatic image comprising a dispersion of resin-containing toner particles dispersion in a carrier solution having an electric resistance of 10.sup.9 .OMEGA..multidot.cm or more and a dielectric constant of 3.5 or less and containing said charge-regulatory agent prepared as mentioned above.When an electrostatic latent image is developed with the present liquid developer containing the special charge-regulatory agent, an image of excellent resolving power, good half-tone reproduction and excellent gradation may be obtained without the occurence of any image flow.
    Type: Grant
    Filed: September 24, 1986
    Date of Patent: January 12, 1988
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Katsugi Kitatani, Hiroaki Yokoya, Nobuo Suzuki, Masataka Murata
  • Patent number: 4707429
    Abstract: Electrostatic liquid developer consisting essentially of(A) nonpolar liquid having Kauri-butanol value less than 30, present in major amount,(B) thermoplastic resin particles having a metallic soap as defined dispersed therein and average particle size by area being less than 10 .mu.m, and(C) nonpolar liquid soluble ionic or zwitterionic charge director compound. Optionally a colorant and charge adjuvant are present. The electrostatic liquid developer is useful in copying, making proofs including digital color proofs, lithographic printing plates, and resists.
    Type: Grant
    Filed: April 30, 1986
    Date of Patent: November 17, 1987
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Torence J. Trout
  • Patent number: 4702985
    Abstract: Electrostatic liquid developer having improved charging characteristics comprising(A) nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount,(B) thermoplastic resin particles having an average by area particle size of less than 10 .mu.m,(C) nonpolar liquid soluble ionic or zwitterionic compound, and(D) at least one aminoalcohol compound.The electrostatic liquid developer is useful in copying, making proofs including digital color proofs, lithographic printing plates, and resists.
    Type: Grant
    Filed: April 28, 1986
    Date of Patent: October 27, 1987
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: James R. Larson
  • Patent number: RE32883
    Abstract: This invention is directed to a dry electrostatic toner composition containing a resin, a colorant or pigment, and an organic sulfate or sulfonate charge control additive of the following formula: ##STR1## wherein R.sub.1 is an alkyl radical containing from about 12 carbon atoms to about 22 carbon atoms, and preferably from about 14 carbon atoms to 18 carbon atoms, R.sub.2 and R.sub.3 are independently selected from alkyl groups containing from about 1 carbon atom to about 5 carbon atoms, R.sub.4 is an alkylene group containing from about 1 carbon atom to about 5 carbon atoms, R.sub.5 is a tolyl group or an alkyl group containing from about 1 carbon atom to about 3 carbon atoms and n is the number 3 or 4. Such toners, especially when combined with carrier materials, are useful for causing the development of images in an electrophotographic system.
    Type: Grant
    Filed: November 30, 1983
    Date of Patent: March 7, 1989
    Assignee: Xerox Corporation
    Inventor: Chin H. Lu