EP0660193B1 - Iron oxide pigments as charge stabilizers in electrostatic toners - Google Patents

Iron oxide pigments as charge stabilizers in electrostatic toners Download PDF

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Publication number
EP0660193B1
EP0660193B1 EP94118845A EP94118845A EP0660193B1 EP 0660193 B1 EP0660193 B1 EP 0660193B1 EP 94118845 A EP94118845 A EP 94118845A EP 94118845 A EP94118845 A EP 94118845A EP 0660193 B1 EP0660193 B1 EP 0660193B1
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Prior art keywords
charge
iron oxide
toner
iron
electrostatic
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EP94118845A
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German (de)
French (fr)
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EP0660193A1 (en
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Karin Heidrun Dr. Beck
Rainer Dr. Dyllick-Brenzinger
Joerg Dr. Schröder
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BASF SE
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BASF SE
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    • 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
    • G03G9/083—Magnetic toner particles
    • G03G9/0831—Chemical composition of the magnetic components
    • G03G9/0833—Oxides
    • 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
    • G03G9/097—Plasticisers; Charge controlling agents
    • G03G9/09708—Inorganic compounds

Definitions

  • the present invention relates to the new use of Iron oxide pigments ⁇ -iron (III) oxide and / or ⁇ -iron (III) oxide hydrate, which have an average particle diameter of 0.005 to Have 0.05 microns as charge stabilizers in electrostatic Toners.
  • Toner particles are used to develop the electrostatic image via a "magnetic brush", that's one along the field lines Sector magnet aligned carrier particles, to the photoconductor roller transported.
  • the toner particles adhere electrostatically on the carrier particles and received during transport in the Magnetic field due to friction opposite the carrier particles electrostatic charge.
  • the magnetic brush toner particles transferred to the photoconductor roller result in a "Toner image”, which is then transferred to paper or film and is fixed.
  • the toner In order to obtain strong, sharply contoured images, the toner to stabilize its electrostatic charge. Charge controlling agents added.
  • the invention was based on the object of new charge stabilizers to provide with advantageous application properties.
  • iron oxide pigments ⁇ -iron (III) oxide ⁇ -Fe 2 O 3 hematite; CI Pigment Red 101; CI 77491
  • ⁇ -iron (III) oxide hydrates ⁇ -FeO (OH) xH 2 O x about 1 to 7; CI Pigment Yellow 42; CI 77492; Goethit
  • charge stabilizers found in electrostatic toners ⁇ -iron (III) oxide ⁇ -Fe 2 O 3 (hematite; CI Pigment Red 101; CI 77491) and ⁇ -iron (III) oxide hydrates ⁇ -FeO (OH) xH 2 O (x about 1 to 7; CI Pigment Yellow 42; CI 77492; Goethit) and mixtures thereof as charge stabilizers found in electrostatic toners.
  • the iron oxide pigments are finely divided, more transparent Form (highly transparent to semi-transparent) and show one average particle diameter of 0.005 to 0.05 ⁇ m, preferred 0.01 to 0.05 ⁇ m.
  • the values mentioned refer to acicular pigment particles perpendicular to the diameter Longitudinal expansion.
  • the iron oxide pigments according to the invention can advantageously be used as Charge stabilizers in the manufacture of electrostatic Toners for one and especially two component developers be used.
  • the main components of an electrostatic toner are usually the binder and the charge stabilizer, the usually 0.01 to 10% by weight, in particular 0.01 to 5% by weight of the finished toner.
  • the toner binders are mostly thermoplastic polymers with softening points from 40 to 200 ° C, preferably 50 to 130 ° C and particularly preferably 65 to 115 ° C.
  • Suitable binders are polystyrene, copolymers made of styrene and an acrylate or methacrylate, copolymers Styrene and butadiene and / or acrylonitrile, polyacrylates, polymethacrylates, Copolymers of an acrylate or methacrylate and Vinyl chloride or vinyl acetate, polyvinyl chloride, copolymers Vinyl chloride and vinylidene chloride or vinyl acetate, polyester resins, Epoxy resins, polyamides and polyurethanes.
  • the electrostatic toners can also be others Components such as waxes, flow agents, colorants and magnetic attractable materials included.
  • Organic dyes or pigments such as Nigrosine, aniline blue, 2,9-dimethylquinacridone, C.I. Disperse Red 15 (C.I. 60 710), C.I. Solvent Red 19 (C.I. 26 050), C.I. pigment Blue 15 (C.I. 74 160), C.I. Pigment Blue 22 (C.I. 69 810) or C.I. Solvent Yellow 16 (C.I. 12 700) or inorganic pigments, such as soot, red lead, yellow lead oxide or chrome yellow. Generally exceeds the amount of colorant in the toner not 15% by weight based on the weight of the toner.
  • the magnetically attractable materials can be, for example, iron, nickel, chromium oxide, iron oxide or a ferrite of the formula MeFe 2 O 4 , in which Me is a divalent metal, for example iron, cobalt, zinc, nickel or manganese.
  • the toner production can be done using the invention
  • Charge stabilizers are carried out as usual, e.g. by Mixing the ingredients in solid form in a kneader and subsequent pulverization or by dispersing the others Components in the molten binder using known ones Mixing or kneading machines, then cooling the Melt to a solid mass and grind to particles of the desired Particle size (usually 0.1 to 50 ⁇ m).
  • the toner preparation thus obtained can directly, e.g. in a xerographic imaging system, be used or first a drying process, for example spray drying, freeze drying or Evaporation of the solvent, followed by grinding to be subjected to the desired particle size.
  • Iron oxide pigments have good overall application properties out. They are insensitive to moisture, thermally stable up to 180 ° C, and above all they give a toner preparation a favorable electrostatic charge profile, i.e. the toner can be charged quickly and highly. Moreover keep this charge constant at a high level.

Description

Die vorliegende Erfindung betrifft die neue Verwendung der Eisenoxidpigmente α-Eisen(III)oxid und/oder α-Eisen(III)oxid-hydrat, die einen mittleren Teilchendurchmesser von 0,005 bis 0,05 µm aufweisen, als Ladungsstabilisatoren in elektrostatischen Tonern.The present invention relates to the new use of Iron oxide pigments α-iron (III) oxide and / or α-iron (III) oxide hydrate, which have an average particle diameter of 0.005 to Have 0.05 microns as charge stabilizers in electrostatic Toners.

In der Elektrophotographie wird durch selektive Belichtung einer elektrostatisch aufgeladenen Photoleiterwalze mit vom zu kopierenden Original reflektiertem Licht ein latentes elektrostatisches Bild erzeugt. Beim Laserdrucker geschieht dies durch einen Laserstrahl.In electrophotography, selective exposure exposes one electrostatically charged photoconductor roller with from to copying original reflected light a latent electrostatic Image created. With the laser printer, this happens through a laser beam.

Zur Entwicklung des elektrostatischen Bildes werden Tonerteilchen über eine "Magnetbürste", das sind entlang der Feldlinien eines Sektormagneten ausgerichtete Carrierteilchen, zur Photoleiterwalze transportiert. Die Tonerteilchen haften dabei elektrostatisch an den Carrierteilchen und erhalten beim Transport im Magnetfeld durch Reibung eine den Carrierteilchen entgegengesetzte elektrostatische Aufladung. Die so von der Magnetbürste auf die Photoleiterwalze übertragenen Tonerteilchen ergeben ein "Tonerbild", das anschließend auf Papier oder Folie übertragen und fixiert wird.Toner particles are used to develop the electrostatic image via a "magnetic brush", that's one along the field lines Sector magnet aligned carrier particles, to the photoconductor roller transported. The toner particles adhere electrostatically on the carrier particles and received during transport in the Magnetic field due to friction opposite the carrier particles electrostatic charge. The magnetic brush toner particles transferred to the photoconductor roller result in a "Toner image", which is then transferred to paper or film and is fixed.

Um kräftige, konturenscharfe Bilder zu erhalten, werden dem Toner zur Stabilisierung seiner elektrostatischen Aufladung sog. Ladungsstabilisatoren (charge controlling agents) zugesetzt.In order to obtain strong, sharply contoured images, the toner to stabilize its electrostatic charge. Charge controlling agents added.

An die Ladungsstabilisatoren sind dabei eine Reihe von Anforderungen zu stellen: Sie müssen die Fähigkeit zur Entwicklung des latenten elektrostatischen Bildes zu einem farbstarken sichtbaren Bild besitzen. Weiterhin müssen sie leicht in der Tonerzubereitung verteilbar sein, um störungsfreie, konturenscharfe und gleichförmige Bilder zu erzeugen. Nicht zuletzt müssen sie unempfindlich gegen Feuchtigkeit sein und eine hohe thermische Stabilität aufweisen.There are a number of requirements for the charge stabilizers to face: You must have the ability to develop the latent electrostatic image to a brightly colored visible Own picture. Furthermore, they need to be easy in the toner preparation be redistributable to get trouble-free, sharp contours and to produce uniform images. Last but not least, they have to insensitive to moisture and high thermal Have stability.

Diese Anforderungen sind gleichzeitig nur sehr schwer zu erfüllen. Die Ladungsstabilisatoren des Standes der Technik weisen deshalb häufig Mängel in ihrem Eigenschaftsprofil auf. At the same time, these requirements are very difficult to meet. The charge stabilizers of the prior art have therefore often deficiencies in their property profile.

Aus den US-A-5 266 432 und JP-A-26956/1985 sind Metalloxide als Bestandteil von elektrostatischen Tonern bekannt, sie werden jedoch nicht als Ladungsstabilisatoren eingesetzt. FR-A-2 303 317 erwähnt mineralische Substanzen wie Eisen(III)oxid als mögliche Bestandteile von Tonern, nähere Angaben zu diesen Substanzen werden jedoch nicht gemacht. From US-A-5 266 432 and JP-A-26956/1985 are metal oxides as Known component of electrostatic toners, however, they are not used as charge stabilizers. FR-A-2 303 317 mentions mineral substances such as iron (III) oxide as possible Components of toners, details of these substances are however not made.

Der Erfindung lag die Aufgabe zugrunde, neue Ladungsstabilisatoren mit vorteilhaften anwendungstechnischen Eigenschaften bereitzustellen.The invention was based on the object of new charge stabilizers to provide with advantageous application properties.

Demgemäß wurde die Verwendung der Eisenoxidpigmente α-Eisen(III)oxid α-Fe2O3 (Hämatit; C.I. Pigment Red 101; C.I. 77491) und α-Eisen(III)oxidhydrate α-FeO(OH)·xH2O (x etwa 1 bis 7; C.I. Pigment Yellow 42; C.I. 77492; Goethit) sowie von deren Mischungen als Ladungsstabilisatoren in elektrostatischen Tonern gefunden.Accordingly, the use of the iron oxide pigments α-iron (III) oxide α-Fe 2 O 3 (hematite; CI Pigment Red 101; CI 77491) and α-iron (III) oxide hydrates α-FeO (OH) xH 2 O (x about 1 to 7; CI Pigment Yellow 42; CI 77492; Goethit) and mixtures thereof as charge stabilizers found in electrostatic toners.

Die Eisenoxidpigmente liegen dabei in feinteiliger transparenter Form (hochtransparent bis halbtransparent) vor und weisen einen mittleren Teilchendurchmesser von 0,005 bis 0,05 µm, bevorzugt 0,01 bis 0,05 µm, auf. Die genannten Werte beziehen sich bei nadelförmigen Pigmentteilchen auf den Durchmesser senkrecht zur Längsausdehnung.The iron oxide pigments are finely divided, more transparent Form (highly transparent to semi-transparent) and show one average particle diameter of 0.005 to 0.05 μm, preferred 0.01 to 0.05 µm. The values mentioned refer to acicular pigment particles perpendicular to the diameter Longitudinal expansion.

Diese Eisenoxidpigmente sind allgemein bekannt. Angaben zu ihrer Herstellung können beispielsweise Römpps Chemie-Lexikon, 8. Aufl., Band 2, S. 1066-1067 (1981) entnommen werden.These iron oxide pigments are generally known. Details of their For example, Römpps Chemie-Lexikon, 8th ed., Volume 2, pp. 1066-1067 (1981).

Die erfindungsgemäßen Eisenoxidpigmente können vorteilhaft als Ladungsstabilisatoren bei der Herstellung von elektrostatischen Tonern für Ein- und insbesondere Zweikomponenten-Entwickler verwendet werden. The iron oxide pigments according to the invention can advantageously be used as Charge stabilizers in the manufacture of electrostatic Toners for one and especially two component developers be used.

Die wichtigsten Bestandteile eines elektrostatischen Toners sind in der Regel das Bindemittel und der Ladungsstabilisator, der üblicherweise 0,01 bis 10 Gew.-%, insbesondere 0,01 bis 5 Gew.-% des fertigen Toners ausmacht.The main components of an electrostatic toner are usually the binder and the charge stabilizer, the usually 0.01 to 10% by weight, in particular 0.01 to 5% by weight of the finished toner.

Bei den Tonerbindemitteln handelt es sich bekanntermaßen meist um thermoplastische Polymere mit Erweichungspunkten von 40 bis 200°C, bevorzugt 50 bis 130°C und besonders bevorzugt 65 bis 115°C.As is known, the toner binders are mostly thermoplastic polymers with softening points from 40 to 200 ° C, preferably 50 to 130 ° C and particularly preferably 65 to 115 ° C.

Beispiele für geeignete Bindemittel sind Polystyrol, Copolymere aus Styrol und einem Acrylat oder Methacrylat, Copolymere aus Styrol und Butadien und/oder Acrylnitril, Polyacrylate, Polymethacrylate, Copolymere aus einem Acrylat oder Methacrylat und Vinylchlorid oder Vinylacetat, Polyvinylchlorid, Copolymere aus Vinylchlorid und Vinylidenchlorid oder Vinylacetat, Polyesterharze, Epoxyharze, Polyamide und Polyurethane.Examples of suitable binders are polystyrene, copolymers made of styrene and an acrylate or methacrylate, copolymers Styrene and butadiene and / or acrylonitrile, polyacrylates, polymethacrylates, Copolymers of an acrylate or methacrylate and Vinyl chloride or vinyl acetate, polyvinyl chloride, copolymers Vinyl chloride and vinylidene chloride or vinyl acetate, polyester resins, Epoxy resins, polyamides and polyurethanes.

Gewünschtenfalls können die elektrostatischen Toner auch weitere Bestandteile wie Wachse, Fließmittel, Farbmittel und magnetisch anziehbare Materialien enthalten.If desired, the electrostatic toners can also be others Components such as waxes, flow agents, colorants and magnetic attractable materials included.

Als Farbmittel können organische Farbstoffe oder Pigmente, wie Nigrosin, Anilinblau, 2,9-Dimethylchinacridon, C.I. Disperse Red 15 (C.I. 60 710), C.I. Solvent Red 19 (C.I. 26 050), C.I. Pigment Blue 15 (C.I. 74 160), C.I. Pigment Blue 22 (C.I. 69 810) oder C.I. Solvent Yellow 16 (C.I. 12 700) oder anorganische Pigmente, wie Ruß, Rotblei, gelbes Bleioxid oder Chromgelb, dienen. Allgemein überschreitet die Menge des im Toner vorhandenen Farbmittels nicht 15 Gew.-%, bezogen auf das Gewicht des Toners.Organic dyes or pigments such as Nigrosine, aniline blue, 2,9-dimethylquinacridone, C.I. Disperse Red 15 (C.I. 60 710), C.I. Solvent Red 19 (C.I. 26 050), C.I. pigment Blue 15 (C.I. 74 160), C.I. Pigment Blue 22 (C.I. 69 810) or C.I. Solvent Yellow 16 (C.I. 12 700) or inorganic pigments, such as soot, red lead, yellow lead oxide or chrome yellow. Generally exceeds the amount of colorant in the toner not 15% by weight based on the weight of the toner.

Die magnetisch anziehbaren Materialien können beispielsweise Eisen, Nickel, Chromoxid, Eisenoxid oder ein Ferrit der Formel MeFe2O4, worin Me ein zweiwertiges Metall, z.B. Eisen, Kobalt, Zink, Nickel oder Mangan, bedeutet, sein.The magnetically attractable materials can be, for example, iron, nickel, chromium oxide, iron oxide or a ferrite of the formula MeFe 2 O 4 , in which Me is a divalent metal, for example iron, cobalt, zinc, nickel or manganese.

Die Tonerherstellung kann bei der Verwendung der erfindungsgemäßen Ladungsstabilisatoren wie üblich erfolgen, z.B. durch Vermischen der Bestandteile in fester Form in einem Kneter und anschließendes Pulverisieren oder durch Dispergieren der weiteren Bestandteile im geschmolzenen Bindemittel unter Verwendung bekannter Misch- oder Knetmaschinen, anschließendes Abkühlen der Schmelze zu einer festen Masse und Vermahlen zu Teilchen der gewünschten Teilchengröße (in der Regel 0,1 bis 50 µm).The toner production can be done using the invention Charge stabilizers are carried out as usual, e.g. by Mixing the ingredients in solid form in a kneader and subsequent pulverization or by dispersing the others Components in the molten binder using known ones Mixing or kneading machines, then cooling the Melt to a solid mass and grind to particles of the desired Particle size (usually 0.1 to 50 µm).

Eine weitere Möglichkeit besteht darin, das Bindemittel in einem geeigneten Lösungsmittel zu lösen und den Ladungsstabilisator fein in dieser Lösung zu dispergieren. Die so erhaltene Tonerzubereitung kann direkt, z.B. in einem xerographischen Bildaufzeichnungssystem, verwendet werden oder zuerst einem Trocknungsprozeß, beispielsweise Sprühtrocknung, Gefriertrocknung oder Abdampfen des Lösungsmittels, mit anschließendem Vermahlen zur gewünschten Teilchengröße unterworfen werden.Another option is to combine the binder in one suitable solvent and the charge stabilizer disperse finely in this solution. The toner preparation thus obtained can directly, e.g. in a xerographic imaging system, be used or first a drying process, for example spray drying, freeze drying or Evaporation of the solvent, followed by grinding to be subjected to the desired particle size.

Die erfindungsgemäß als Ladungsstabilisatoren zu verwendenden Eisenoxidpigmente zeichnen sich durch insgesamt gute Anwendungseigenschaften aus. Sie sind unempfindlich gegenüber Feuchtigkeit, thermisch bis 180°C stabil, und vor allem verleihen sie einer Tonerpräparation ein günstiges elektrostatisches Aufladungsprofil, d.h. die Toner können schnell und hoch aufgeladen werden. Außerdem halten sie diese Aufladung auf hohem Niveau konstant.Those to be used according to the invention as charge stabilizers Iron oxide pigments have good overall application properties out. They are insensitive to moisture, thermally stable up to 180 ° C, and above all they give a toner preparation a favorable electrostatic charge profile, i.e. the toner can be charged quickly and highly. Moreover keep this charge constant at a high level.

BeispieleExamples

  • I. Herstellung von erfindungsgemäßen Ladungsstabilisatoren enthaltenden elektrostatischen Tonern
  • Als Bindemittel für die Toner wurden
  • Harz A: ein nicht vernetztes Styrol/Butylacrylatharz oder
  • Harz B: ein lineares, nicht vernetztes Polyesterharz eingesetzt.
  • Die Tonerherstellung erfolgte entweder durch
    • Gefriertrocknung (Methode G),
      indem 0,2 g Eisenoxidpigment in eine Lösung von 10 g des jeweils verwendeten Harzes in 100 ml p-Xylol dispergiert wurden und die erhaltene Suspension anschließend gefriergetrocknet wurde, oder durch
    • Knetung (Methode K),
      indem 0,2 g Eisenoxidpigment und 10 g des jeweils verwendeten Harzes intensiv in einem Mixer gemischt, bei 120°C geknetet, extrudiert und gemahlen wurden, wobei Tonerteilchen einer mittleren Partikelgröße von 50 µm erzeugt wurden.
  • In der Tabelle sind Einzelheiten zu den hergestellten Tonern zusammengestellt, wobei auch die als Ladungsstabilisatoren eingesetzten Eisenoxidpigmente näher charakterisiert werden.
  • II. Herstellung und Prüfung der Developer
  • Zur Herstellung der Developer wurden die so hergestellten Toner jeweils im Gewichtsverhältnis 1:99 mit einem Stahlcarrier der mittleren Teilchengröße 100 µm vermischt und auf einem Rollenbock aktiviert.
  • Nach 10, 30, 60 und 120 min wurden jeweils Proben entnommen und deren elektrostatische Aufladung in einem g/m-Meter (Fa. Epping, Neufahrn) bestimmt.
  • Dazu wurden jeweils 5 g des Developers in eine mit einem Elektrometer gekoppelte Hard-blow-off-Zelle, in die Siebe der Maschenweite 63 µm eingesetzt waren, eingewogen. Durch Ausblasen mit einem kräftigen Luftstrom (ca. 4000 cm3/min) und gleichzeitiges Absaugen wurden die Tonerteilchen nahezu vollständig entfernt, während die Carrierteilchen durch die Siebe in der Meßzelle zurückgehalten wurden. Dann wurde die Aufladung des Carriers, die der Aufladung der Tonerteilchen mit umgekehrtem Vorzeichen entspricht, am Elektrometer abgelesen, durch Zurückwägung der Meßzelle auf das Gewicht des ausgeblasenen Toners bezogen und so dessen elektrostatische Aufladung g/m [µC/g] bestimmt.
  • Die erhaltenen Meßergebnisse sind in der Tabelle zusammengefaßt.
    • Figure 00070001
  • I. Production of electrostatic toners containing charge stabilizers according to the invention
  • As binders for the toners
  • Resin A: an uncrosslinked styrene / butyl acrylate resin or
  • Resin B: a linear, non-crosslinked polyester resin is used.
  • The toner production was done either by
    • Freeze drying (method G),
      by dispersing 0.2 g of iron oxide pigment in a solution of 10 g of the resin used in each case in 100 ml of p-xylene and then freeze-drying the suspension obtained, or by
    • Kneading (method K),
      in that 0.2 g of iron oxide pigment and 10 g of the resin used in each case were mixed intensively in a mixer, kneaded at 120 ° C., extruded and ground, producing toner particles with an average particle size of 50 μm.
  • Details of the toners produced are compiled in the table, the iron oxide pigments used as charge stabilizers also being characterized in more detail.
  • II. Development and testing of developers
  • To produce the developers, the toners thus produced were each mixed in a weight ratio of 1:99 with a steel carrier with an average particle size of 100 μm and activated on a roller stand.
  • Samples were taken after 10, 30, 60 and 120 minutes and their electrostatic charge was determined in a g / m meter (from Epping, Neufahrn).
  • For this purpose, 5 g of the developer were weighed into a hard-blow-off cell coupled with an electrometer, into which sieves with a mesh size of 63 μm were inserted. The toner particles were almost completely removed by blowing out with a strong air stream (approx. 4000 cm 3 / min) and simultaneous suction, while the carrier particles were retained in the measuring cell by the sieves. Then the charge on the carrier, which corresponds to the charge on the toner particles with the opposite sign, was read off on the electrometer, and the weight of the toner blown out was determined by weighing the measuring cell back, and its electrostatic charge g / m [μC / g] was thus determined.
  • The measurement results obtained are summarized in the table.
    • Figure 00070001

    Claims (2)

    1. The use of the iron oxide pigments α-iron(III) oxide and/or α-iron(III) oxide hydrate which have an average particle diameter of from 0.005 to 0.05 µm as charge stabilizers in electrostatic toners.
    2. Electrostatic toners comprising the iron oxide pigments α-iron(III) oxide or α-iron(III) oxide hydrate which have an average particle diameter of from 0.005 to 0.05 µm as charge stabilizers.
    EP94118845A 1993-12-08 1994-11-30 Iron oxide pigments as charge stabilizers in electrostatic toners Expired - Lifetime EP0660193B1 (en)

    Applications Claiming Priority (2)

    Application Number Priority Date Filing Date Title
    DE4341726A DE4341726A1 (en) 1993-12-08 1993-12-08 Use of metal oxide pigments as charge stabilizers in electrostatic toners
    DE4341726 1993-12-08

    Publications (2)

    Publication Number Publication Date
    EP0660193A1 EP0660193A1 (en) 1995-06-28
    EP0660193B1 true EP0660193B1 (en) 2000-03-15

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    EP (1) EP0660193B1 (en)
    JP (1) JPH07199544A (en)
    CA (1) CA2137502A1 (en)
    DE (2) DE4341726A1 (en)

    Families Citing this family (2)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    US5830616A (en) * 1995-07-19 1998-11-03 Iwatsu Electric Co., Inc. Magnetic latent image developing toner
    DE19628933A1 (en) * 1995-07-19 1997-01-23 Iwatsu Electric Co Ltd Magnetic toner for developing latent or hidden image in electrography or electric printing

    Family Cites Families (6)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    AU503243B2 (en) * 1975-02-21 1979-08-30 Kanebo Limited Toner for electrostatic printing of sheetlike materials
    US4404270A (en) * 1980-05-22 1983-09-13 Hitachi Chemical Company, Ltd. Positively chargeable powdered electrophotographic toner containing dialkyl tin oxide charge control agent
    JPS5866949A (en) * 1981-10-16 1983-04-21 Fuji Photo Film Co Ltd Capsulated toner
    US5147744A (en) * 1991-02-28 1992-09-15 Xerox Corporation MICR processes with colored encapsulated compositions
    US5266432A (en) * 1991-03-01 1993-11-30 Kao Corporation Hydrophobic polyester toner composition
    FI89537C (en) * 1992-01-09 1993-10-11 Soundek Oy Measuring device for measuring the tensile stress of an optical fiber or corresponding wire

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    DE4341726A1 (en) 1995-06-14
    DE59409208D1 (en) 2000-04-20
    CA2137502A1 (en) 1995-06-09
    JPH07199544A (en) 1995-08-04
    EP0660193A1 (en) 1995-06-28

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