US3585140A - Liquid developer for use in electrophotography containing a terpolymer - Google Patents

Liquid developer for use in electrophotography containing a terpolymer Download PDF

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Publication number
US3585140A
US3585140A US740024A US3585140DA US3585140A US 3585140 A US3585140 A US 3585140A US 740024 A US740024 A US 740024A US 3585140D A US3585140D A US 3585140DA US 3585140 A US3585140 A US 3585140A
Authority
US
United States
Prior art keywords
toner
pigment
liquid
carrier liquid
particles
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US740024A
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English (en)
Inventor
Hazime Machida
Zenjiro Okuno
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Ricoh Co Ltd
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Ricoh Co Ltd
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Filing date
Publication date
Application filed by Ricoh Co Ltd filed Critical Ricoh Co Ltd
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Publication of US3585140A publication Critical patent/US3585140A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G9/00—Developers
    • G03G9/08—Developers with toner particles
    • G03G9/12—Developers with toner particles in liquid developer mixtures
    • G03G9/13—Developers with toner particles in liquid developer mixtures characterised by polymer components
    • G03G9/133—Graft-or block polymers
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G9/00—Developers
    • G03G9/08—Developers with toner particles
    • G03G9/12—Developers with toner particles in liquid developer mixtures
    • G03G9/122—Developers with toner particles in liquid developer mixtures characterised by the colouring agents
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G9/00—Developers
    • G03G9/08—Developers with toner particles
    • G03G9/12—Developers with toner particles in liquid developer mixtures
    • G03G9/125—Developers with toner particles in liquid developer mixtures characterised by the liquid
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G9/00—Developers
    • G03G9/08—Developers with toner particles
    • G03G9/12—Developers with toner particles in liquid developer mixtures
    • G03G9/13—Developers with toner particles in liquid developer mixtures characterised by polymer components
    • G03G9/131—Developers with toner particles in liquid developer mixtures characterised by polymer components obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G9/00—Developers
    • G03G9/08—Developers with toner particles
    • G03G9/12—Developers with toner particles in liquid developer mixtures
    • G03G9/135—Developers with toner particles in liquid developer mixtures characterised by stabiliser or charge-controlling agents
    • G03G9/1355—Ionic, organic compounds
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S430/00—Radiation imagery chemistry: process, composition, or product thereof
    • Y10S430/001—Electric or magnetic imagery, e.g., xerography, electrography, magnetography, etc. Process, composition, or product
    • Y10S430/105—Polymer in developer

Definitions

  • a liquid developer for use in electrophotography comprising a toner dispersed in a carrier liquid, said carrier liquid consisting of a hydrocarbon having a high electric resistance and a low dielectric constant and a surface active agent dissolved in said hydrocarbon, said toner being prepared by having a vinyl copolymer graft-bonded onto the particles of a pigment or by coating the particles of the pigment with said vinyl copolymer, said vinyl copolymer consisting of at least three vinyl monomers of three different types selected from the following three groups, respectively, one (a) of which consisting of vinyl monomers containing functional radicals having a highly increased chemical affinity to said carrier liquid, the second group (b) consisting of vinyl monomers containing functional radicals which are capable of controlling the polarity of the pigment employed, and the last group (c) consisting of vinyl monomers containing functional radicals which are capable of producing tight adhesion or fixing of the toner to the light-sensitive layer of an electrophotographic copying material
  • the present invention is concerned with a liquid developer having a markedly increased, stable developability for use in electrophotography, which is prepared by dispersing a toner-which is obtained by either the graftpolymerization, onto the particles of a pigment, of a vinyl copolymer containing specific functional radicals bonded to said copolymer or by kneading said vinyl copolymer with said particles of pigment-in a carrier liquid which consists of a hydrocarbon of petroleum origin having a relatively high electric resistance and a low dielectric constant and containing a small amount of a surface active agent dissolved therein.
  • Liquid developers for use in electrophotography are prepared by dispersing, in carrier liquid consisting of either a paraffinic or isoparaffinic hydrocarbon, a toner which is obtained by kneading the particles of a pigment together with the additives such as a dispersing agent, a polarity controlling agent, a fixing agent, a drying agent and a stabilizer.
  • the toner which was contained in such a liquid developer of the prior art was of a very complicated structure such that the surfaces of the particles of pigment were coated with a complex mixture of the aforesaid various additives, and such a toner had the drawbacks that its polarity became indistinct or that the suspended ICC toner aggregated together and sedimented to the bottom of the carrier liquid during the storage lasting for an extended period of time or during the repeated use of the liquid developer, causing a marked deterioration of the developability of the liquid developer.
  • This deterioration of the developability of the liquid developer is considered to be due to the loss of the balance-which was maintained satisfactorily during the initial period after the liquid developer was manufactured-between the substances which are dispersed in the carrier liquid and the carrier liquid in which these substances are dispersed, said loss of balance taking place on various occasions, for example, when there is a change in the ambient atmosphere in which the liquid developer is stored, or when the exposed copying materials are immersed in the liquid developer during the process of development, or when there occurs the detachment of the additives off the particles of the pigment, owing to the mutual chemical or physical actions between the additives which are coated on or adhere to the particles of the pigment, or due to the degeneration of the additives per se, or to the extremely complicated composition of the toner.
  • the aforesaid addives in many cases, were composed of those naturally occurring substances such as rosin, asphalt, soya bean oil or linseed oil, so that it was difiicult to obtain additives having uniform chemical properties and a uniform composition. Accordingly, it was difficult to manufacture liquid developers having a uniform developability and uniform quality.
  • Another object of the present invention is to provide a liquid developer for use in electrophotography which can be manufactured as products uniform in their quality as well as their abilities and properties, by the use of synthetic substances as the components of the toner, especially by the use of synthetic resins (copolymers) which are bonded to or coated on the particles of a pigment.
  • a liquid developer for use in electrophotography which is manufactured by dispersing a toner in the aforesaid carrier liquid consisting of a hydrocarbon of petroleum origin, said toner being prepared by having a vinyl copolymer graft-copolymerized onto the particles of a pigment such as carbon black (Cl. No. 77266), aniline black, spirit black (Cl. -No. 77267), alkali blue, phthalocyanine blue (C.I. No. 74160), crystal violet (Cl. No. 42555), congo red ((3.1. No. 22120), channel carbon black (C.I. No. 72266) and oil black (Cl. No. 77267), or by kneading said vinyl copolymer with said particles of pigment, said vinyl copolymer consisting of at least three vinyl monomers of different types selected from the following three groups,
  • the compounds of group (a) have functional radicals having specially markedly increased chemical atiinity to the carrier liquid consisting of hydrocarbons of petroleum origin.
  • the compound of group (b) possess functional radicals which have chemical afiinity to one of the functional radicals of the surface active agent which is contained in the carrier liquid consisting of a hydrocarbon of petroleum origin, and thus the functional radicals of the group (b) compound adsorb the surface active agent, while another of the functional radicals of the surface active agent which is not adsorbable to the compound of group (b) is disposed on the side of the solvent of petroleum origin, and this another of the radicals of the surface active agent determines the polarity and the interfacial potential of the particles of the pigment.
  • the polarity of the toner is regulated to be either positive or negative and also there is imparted a sufficient interfacial potential of the toner.
  • the toner forms, in the liquid developer, the socalled micell structure in which the molecules of the surface active agent are attracted to the toner, resulting in an improvement in the dispersability of the toner in the carrier liquid and also in maintaininng a zeta potential which is sufficient for quickly causing electrophoresis to take place, so that these compounds or group (b) are useful in the formation of a clear copied image on the copying material when the latter is developed.
  • the compounds of group process functional radicals which are capable of exhibiting an action useful in the production of a tight adhesion of the toner onto the lightsensitive layer of the copying material, so that these compounds of group (c) are useful in the fixing of the copied image onto the copying material.
  • the carrier liquid in which the aforesaid toner is dispersed and which can be applied to the present invention it is possible to use any one of the carrier liquids which have been employed in the conventional liquid developers for use in electrophotography in general. More specifically, it is possible to use both of the conventional paraftinic and isoparafiinic hydrocarbons of petroleum origin having an electric resistance of t2-cm or more and a dielectric constant of 3 or smaller.
  • the isoparafiinic hydrocarbons the use of those which are sold under the trade name of ISOPAR H (a product of ESSO Standard Oil Inc.) and NAPHTHA No. 6 (a product of Shell Oil Company of USA.) is suitable.
  • the surface active agents which are dissolved in the carrier liquid and which can be used in the present invention there are, for example, those metal salts consisting of naphthenic acid and metals such as manganese, cobalt, nickel, zinc, chromium, magnesium, lead, iron, zirconium, calcium and aluminum; metal salts consisting of such acids as stearic acid, dodecylic acid or palmitic acid and said metals; cationic surface active agents such as lauryltrimethylammonium chloride, stearylbetaine and polyoxyethylene stearylamine; commercial cationic and anionic surface active agents of a wide variety such as the cationic surface active agent which is manufactured and sold by Kao Soap, Ltd.
  • a toner is dispersed in a carrier liquid in which such a surface active agent as mentioned above is dissolved, it is desirable to fisrt disperse a kneaded or graft-copolymerized toner in a hydrocarbon of petroleum origin, the amount of said hydrocarbon being 3 to 5 times that of the toner, and then to add and disperse the resulting concentrated toner liquid (hereinafter to be referred to simply as conc. toner) in a still greater amount of the carrier liquid which consists of the same hydrocarbon.
  • conc. toner the desirable amount of such a surface active agent which is dissolved in the carrier liquid consisting of said hydrocarbon is in the range of from 10 gr. to 10 gr. per 1000 gr. of the carrier liquid.
  • the liquid developer according to the present invention has a number of advantages, for example, the toner which is contained in said developer is so firm in the bond between the particles of the pigment and the resin (copolymer) which adheres thereto that there occurs no detachment of the resin from the particles of the pigment. Moreover, the toner is of a very satisfactory dispersability in the carrier liquid owing to the mutual actions between the resin (copolymer) of the toner and the surface active agent which is contained in the carrier liquid. Furthermore, the toner is of a very distinct positive or negative polarity by virtue of the adequate combination of the respective components of the toner.
  • the copolymers having the compositions shown in Table 1 were prepared in the following manner. First, the respective component monomers were added to toluene or benzene. To the resulting mixture was added a reaction initiator consisting of azobisisobutylonitrile or benzoyl peroxide in an amount ranging from 0.7% to 1.0% of the total weight of the solvent. The resulting mixture was then subjected to polymerization by heating the same at a temperature ranging from 60 C. to C. for 5 to 10 hours in a nitrogen atmosphere.
  • the kneading which is referred to in the column Graft copolymerized or kneaded in the Table 1 was conducted by placing the vinyl copolymer which was obtained in the manner as has been described above and also particles of a pigment in a ball mill and they were kneaded therein.
  • the resulting kneaded mixture was dispersed in a carrier liquid of an amount 3 to 5 times that of the mixture, and thus a so-called conc. toner was prepared.
  • This conc. toner was then dispersed in a carrier liquid containing a surface active agent dissolved therein, and thus a liquid developer for use in electrophotography was obtained.
  • the toner which was prepared by the graft-copolymerization of a vinyl copolymer and the particles of a pigment was obtained by first placing the particles of the pigment together with the aforesaid three different types of vinyl monomers in a ball mill or a kneader at the time a vinyl copolymer was synthesized from these monomers; and then in a manner similar to that described in connection with the toner prepared by kneading, they were allowed to react therebetween in the ball mill or the kneader.
  • control liquid developers for use in electrophotography in the following manner.
  • a resin which was a copolymer of lauryl methacrylate and dimethylaminoethyl methacrylate
  • a surface active agent which consisted of manganese naphthenate (containing of man- 10 ganese)
  • an isoparaffinic hydrocarbon (ISOPAR H) was added to the resulting mixture in an amount 5 times the total weight of said particles of pigment and said resin, and the resulting mixture was dispersed in a ball mill to thereby prepare a conc. toner. Finally, this conc. toner was dispersed in 1000 cc. of a carrier liquid (ISOPAR H).
  • liquid developers of the present invention showed no appreciable deterioration of the polarity at the end of the storage lasting for 12 months. Whereas, a deterioration of the polarity was noted on the control liquid developers at the end of 3 months.
  • the density of the copied images which were formed on the copying materials was measured. After storing the respective liquid developers for 3 consecutive months, they were used in the developing process to observe how their developability changed due to the storage. The re- 0 sult was that the liquid developer of the present invention showed a reduction in the density of the copied images, which was noted to be about 7%. Whereas, the control liquid developers showed a reduction of about 30%.
  • a liquid developer for use in electrophotography is provided.
  • a carrier liquid selected from the group consisting of paraffinic and isoparafiinic hydrocarbons having an electric resistance of not less than 10 Q-cm. and a dielectric constant of not greater than 3;
  • a small amount of at least one surface active agent dissolved in said carrier liquid and selected from the group consisting of (1) the manganese, cobalt, nickel, zinc, chromium, magnesium, lead, iron, zirconium, calcium and aluminum salts of naphthenic acid, stearic acid, dodecylic acid and palmitic acid, (2) lauryltrimethylammonium chloride, (3) stearylbetainc and (4) polyoxyethylene stearylamine; and
  • a toner dispersed in said carrier liquid said toner consisting essentially of fine particles of at least one pigment selected from the group consisting of Carbon Black (C.I. No. 77266), Aniline Black (C.I. No. 77267), Spirit Black (C.I. No. 77267), Alkali Blue (C.I. No. 42555), Phthalocyanine Blue (C.I. No. 74160), Crystal Violet (C.I. No. 42555), Congo Red (C.I. No. 22120), Channel Carbon Black (01. No. 77266) and Oil Black (C.I. No.
  • alkyl acrylates and methacrylates in which the alkyl has 8 to 19 carbon atoms; monomer group-(b):

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Liquid Developers In Electrophotography (AREA)
US740024A 1967-07-10 1968-06-26 Liquid developer for use in electrophotography containing a terpolymer Expired - Lifetime US3585140A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4406267 1967-07-10

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US3585140A true US3585140A (en) 1971-06-15

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Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3849165A (en) * 1971-06-03 1974-11-19 Eastman Kodak Co Liquid electrographic development process
US3860552A (en) * 1973-09-12 1975-01-14 Pitney Bowes Inc Copolymer compositions and method of preparation
US3909433A (en) * 1972-07-12 1975-09-30 Agfa Gevaert Nv Liquid electrophotographic developing compositions
US3926825A (en) * 1973-05-29 1975-12-16 Xerox Corp Liquid developer composition and process for preparing same
US3959153A (en) * 1969-05-28 1976-05-25 Fuji Photo Film Co., Ltd. Manufacturing method for electrophotographic developing agent
US3968044A (en) * 1974-02-01 1976-07-06 Rank Xerox Ltd. Milled liquid developer
US3969238A (en) * 1972-08-15 1976-07-13 Canon Kabushiki Kaisha Liquid developer for electrophotography and process for developing latent images
US3976808A (en) * 1973-05-29 1976-08-24 Xerox Corporation Imaging systems
US3977983A (en) * 1974-05-17 1976-08-31 Canon Kabushiki Kaisha Liquid developer for use in development of an electrostatic latent image comprising a copolymer containing an amino group converted into a quaternary ammonium salt or hydroxide
US3991226A (en) * 1974-01-14 1976-11-09 Philip A. Hunt Chemical Corporation Method of creating an image using hybrid liquid toners
US4040970A (en) * 1974-05-17 1977-08-09 Canon Kabushiki Kaisha Liquid developer for developing an electrostatic latent image
US4060493A (en) * 1975-07-10 1977-11-29 Ricoh Co., Ltd. Liquid electrostatic developer
US4081391A (en) * 1974-09-03 1978-03-28 Ricoh Co., Ltd. Liquid developer for use in electrophotography
US4085058A (en) * 1973-04-04 1978-04-18 Iwatsu Electric Co., Ltd. Electrophotographic liquid developer containing a graft copolymer of a cyclized rubber
US4157973A (en) * 1974-05-15 1979-06-12 Pitney-Bowes, Inc. Copolymer compositions and method of preparation
US4219614A (en) * 1977-09-29 1980-08-26 Eastman Kodak Company Electrophoretic migration imaging composition and process using same
US4764447A (en) * 1985-07-17 1988-08-16 Ricoh Co., Ltd. Non-aqueous type resin dispersion and electrophotographic developer containing said resin
WO1997000295A1 (fr) 1995-06-14 1997-01-03 Nippon Shokubai Co., Ltd. Polymere greffe a base de noir de carbone, son procede de production et son utilisation
US5952048A (en) * 1994-06-17 1999-09-14 Ricoh Company, Ltd. Ink composition and recording method using the same
US7049040B2 (en) 1996-12-26 2006-05-23 Ticona Gmbh Electrostatically charged image developing toner containing a polyolefin resin having a cyclic structure

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3959153A (en) * 1969-05-28 1976-05-25 Fuji Photo Film Co., Ltd. Manufacturing method for electrophotographic developing agent
US3849165A (en) * 1971-06-03 1974-11-19 Eastman Kodak Co Liquid electrographic development process
US3909433A (en) * 1972-07-12 1975-09-30 Agfa Gevaert Nv Liquid electrophotographic developing compositions
US3969238A (en) * 1972-08-15 1976-07-13 Canon Kabushiki Kaisha Liquid developer for electrophotography and process for developing latent images
US4085058A (en) * 1973-04-04 1978-04-18 Iwatsu Electric Co., Ltd. Electrophotographic liquid developer containing a graft copolymer of a cyclized rubber
US3926825A (en) * 1973-05-29 1975-12-16 Xerox Corp Liquid developer composition and process for preparing same
US3976808A (en) * 1973-05-29 1976-08-24 Xerox Corporation Imaging systems
US3860552A (en) * 1973-09-12 1975-01-14 Pitney Bowes Inc Copolymer compositions and method of preparation
US3991226A (en) * 1974-01-14 1976-11-09 Philip A. Hunt Chemical Corporation Method of creating an image using hybrid liquid toners
US3968044A (en) * 1974-02-01 1976-07-06 Rank Xerox Ltd. Milled liquid developer
US4157973A (en) * 1974-05-15 1979-06-12 Pitney-Bowes, Inc. Copolymer compositions and method of preparation
US4040970A (en) * 1974-05-17 1977-08-09 Canon Kabushiki Kaisha Liquid developer for developing an electrostatic latent image
US3977983A (en) * 1974-05-17 1976-08-31 Canon Kabushiki Kaisha Liquid developer for use in development of an electrostatic latent image comprising a copolymer containing an amino group converted into a quaternary ammonium salt or hydroxide
US4081391A (en) * 1974-09-03 1978-03-28 Ricoh Co., Ltd. Liquid developer for use in electrophotography
US4060493A (en) * 1975-07-10 1977-11-29 Ricoh Co., Ltd. Liquid electrostatic developer
US4219614A (en) * 1977-09-29 1980-08-26 Eastman Kodak Company Electrophoretic migration imaging composition and process using same
US4764447A (en) * 1985-07-17 1988-08-16 Ricoh Co., Ltd. Non-aqueous type resin dispersion and electrophotographic developer containing said resin
US5952048A (en) * 1994-06-17 1999-09-14 Ricoh Company, Ltd. Ink composition and recording method using the same
WO1997000295A1 (fr) 1995-06-14 1997-01-03 Nippon Shokubai Co., Ltd. Polymere greffe a base de noir de carbone, son procede de production et son utilisation
EP0787777A4 (en) * 1995-06-14 2001-10-04 Nippon Catalytic Chem Ind GASKET POLYMER CONTAINING SOOT
US7049040B2 (en) 1996-12-26 2006-05-23 Ticona Gmbh Electrostatically charged image developing toner containing a polyolefin resin having a cyclic structure

Also Published As

Publication number Publication date
DE1772825A1 (de) 1970-09-10
DE1772825B2 (de) 1972-07-20
BE717572A (en:Method) 1968-12-16

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