[go: up one dir, main page]

EP0382285B1 - Partikeltonermaterial - Google Patents

Partikeltonermaterial Download PDF

Info

Publication number
EP0382285B1
EP0382285B1 EP90200217A EP90200217A EP0382285B1 EP 0382285 B1 EP0382285 B1 EP 0382285B1 EP 90200217 A EP90200217 A EP 90200217A EP 90200217 A EP90200217 A EP 90200217A EP 0382285 B1 EP0382285 B1 EP 0382285B1
Authority
EP
European Patent Office
Prior art keywords
styrene
toner particles
composition according
carbon atoms
copolymer
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
EP90200217A
Other languages
English (en)
French (fr)
Other versions
EP0382285A1 (de
Inventor
Piet Kok
Luc Jerome Vanmaele
Serge Martin Tavernier
Hedwig Etienne De Deyne
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Agfa Gevaert NV
Original Assignee
Agfa Gevaert NV
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Agfa Gevaert NV filed Critical Agfa Gevaert NV
Priority to EP90200217A priority Critical patent/EP0382285B1/de
Publication of EP0382285A1 publication Critical patent/EP0382285A1/de
Application granted granted Critical
Publication of EP0382285B1 publication Critical patent/EP0382285B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

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
    • G03G9/097—Plasticisers; Charge controlling agents
    • G03G9/09733—Organic compounds
    • G03G9/09758—Organic compounds comprising a heterocyclic ring

Definitions

  • the present invention relates to a toner particles composition and to a developer composition comprising these toner particles for developing electrostatic charge patterns or images as claimed in claims 1 and 9, respectively.
  • an electrostatic latent charge image is obtained with an electrophotographic material typically comprising a coating of a photoconductive insulating material on a conductive support. Said coating is given a uniform surface charge in the dark and is then exposed to an image pattern of activating electromagnetic radiation such as light or X-rays.
  • the charge on the photoconductive element is dissipated in the irradiated area to form an electrostatic charge pattern which is then developed with an electroscopic marking material.
  • the marking material or toner whether carried in an insulating liquid or in the form of a dry powder deposits on the exposed surface in accordance with either the charge pattern or the discharge pattern as desired. If the photoconductive element is of the reusable type, e.g. a selenium coated drum, the toner image is transferred to another surface such as paper and then fixed to provide a copy of the original.
  • a variety of electrostatic developers are available for use in developing electrostatic charge patterns.
  • carrier particles are mixed with toner particles electrostatically adhering thereto.
  • the carrier may comprise various materials and as the name implies, serves as a medium for carrying the electrostatically responsive marking particles to the charge pattern to be developed.
  • carrier-toner developers are dry developers known for use in cascade development as described e.g. in U.S.Patent Specification No. 2,618,552 and for use in magnetic brush development as described e.g. in U.S.Patent Specification No. 3,003,462.
  • the cascade development technique is carried out by rolling or cascading across the electrostatic latent image bearing surface, a developing mixture composed of relatively large carrier particles, each having a number of electrostatically adhering toner particles on its surface. As this mixture rolls across the image-bearing surface, the toner particles are electrostatically deposited on the charged portions of the image.
  • the magnetic brush development technique involves the use of magnetic means associated with a developing mixture composed of magnetic carrier particles carrying a number of smaller electrostatically adhering toner particles.
  • the developer composition is maintained during the development cycle in a loose, brushlike orientation by a magnetic field surrounding, for example, a rotatable non-magnetic cylinder having a means with magnetic poles mounted inside.
  • the magnetic carrier particles are attracted to the cylinder by the described magnetic field, and the toner particles are held to the carrier particles by virtue of their opposite electrostatic polarity.
  • the toner acquires an electrostatic charge of a sign opposite to that of the carrier material due to triboelectric charging derived from their mutual frictional interaction.
  • the toner In dry toner development systems the toner is normally a fine powder of natural or synthetic resins having a colorant and a charge controlling agent dissolved or dispersed therein.
  • Known positive charge controlling compounds for use in dry toners are dye bases and salts thereof such as nigrosine dye base and salts described in GB-P 1,253,573.
  • Such charge controlling agents are usually added to the thermoplastic resin to be dispersed in the resin in molten state. Upon cooling the mixture is micropulverized and the particles with desired particle size separated e.g. by wind sifter.
  • Coloured charge controlling substances have the disadvantage that their colour interferes with the colour intensionally given to the toner mass.
  • the inherent colour of the charge controlling substance may form a serious obstacle. Therefore preference is given to the use of colourless charge controlling substances.
  • an electrostatic image developing toner contains as charge controlling agent a piperidine compound corresponding to the following general formula (I) : wherein : R1, R2, R3 and R4 are each 1-6C alkyl, R5 is hydrogen or 1-5C alkyl, R6 is hydrogen or 1-12C alkyl or 3-12C alkenyl, or 7-12C aralkyl; n is an integer of 1-4 and R7 is acyl or N-substituted carbamoyl where n is 1, diacyl, dicarbamoyl or carbonyl where n is 2, triacyl where n is 3 and tetraacyl where n is 4.
  • an electrostatically attractable toner particles composition for use in the development of latent electrostatic images, said toner particles acquiring in the presence of carrier particles a positive charge by triboelectric contact electrification, said composition containing (a) thermoplastic resin(s) as binder in combination with a colorant and a colourless charge controlling agent, characterized in that said colourless charge controlling agent contains in its molecular structure at least one polyalkyl substituted piperidine group and a sterically hindered phenol group, and has the following general formula (A) : wherein : R1 is hydrogen or alkyl having 1 to 4 carbon atoms, R2 is alkyl or hydroxyalkyl, each having 1 to 12 carbon atoms, alkenyl or alkynyl each having 3 or 4 carbon atoms or aralkyl such as benzyl, R3 is hydrogen or methyl, R4 and R5 are each alkyl having 1 to 5 carbon atoms or cycloalkyl having 5
  • said colourless compound is used preferably in an amount in the range of 0.5 to 5 % by weight with respect to the total toner composition.
  • the toner particle according to the present invention may be used as so-called mono-component toner particles or in admixture with carrier particles.
  • the toner particles composition can be prepared by any conventional technique such as spray drying a solution in a suitable volatile solvent or grinding a solidified composition of homogeneously mixed ingredients including a thermoplastic binder, colorant and a colourless positive charge-imparting polymeric amino compound(s) according to said general formula (A).
  • the toner particles have preferably a particle size in the range of 3 to 30 ⁇ m, and more preferably in the range of 5 to 20 ⁇ m.
  • the colourless charge controlling substances are preferably present in dissolved state in the thermoplastic resin binder of the toner, such is not strictly necessary.
  • the colour of the colorant is not that vivid by the opalescent character of the dispersion.
  • a "colloidal" dispersion is mostly obtained when amino-salts and quaternary derivatives of the compounds according general formula (A) are used.
  • the anion(s) of these salts may be of any type known in the art. Suitable anions are e.g. hydroxyl (OH ⁇ ), chloride, iodide, sulfate, ZnCl ⁇ 4, and tolusulfonate.
  • OH ⁇ hydroxyl
  • chloride iodide
  • sulfate sulfate
  • ZnCl ⁇ 4 sulfate
  • tolusulfonate e.g. hydroxyl (OH ⁇ )
  • the affinity of the anion with respect to the carrier particle surface may play a role in the triboelectric charging [ref. the book "Electrophotography” by R.M. Schaffert, The Focal Press - London and New York (1975), p. 559-560].
  • anions of relatively large size are used, e.g. PF - 6 and other large size anions such as the tetraphenylboride anion described for use in liquid electrophoretic developers in US-P 4,525,446.
  • thermoplastic resins having a melting point in the range of 100 to 120°C, glass transition temperature (Tg) larger than 60 °C, with in their structure a major part by weight of aromatic groups, e.g. phenyl groups.
  • Said polymers may contain a minor part by weight of electron donating groups, e.g. alkylamino or arylamino groups to further improve the positive chargeability of the toner.
  • thermoplastic binder being a resin selected from the group consisting of a homopolymer and copolymer of styrene wherein the styrene content is preferably at least 50 mole %.
  • Preferred copolymers of styrene for use in toner material according to the present invention are copolymers of styrene-(meth)acrylic acid esters such as styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-n-butyl acrylate copolymer, styrene-n-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-n-butyl methacrylate copolymer, styrene-isobutyl methacrylate copolymer, styrene-n-octyl methacrylate copolymer, styrene-heptadecyl methacrylate copolymer, copoly(
  • Preferred copolymers containing said group have the following structural formula (B) : wherein : x is 83-87 % by weight y is 0-4 % by weight z is 13-17 % by weight, and have a melting point (ring and ball method) in the range of 106 to 115°C.
  • Said copolymers which may be used separately or in combination can be prepared by common addition polymerisation starting with the monomers involved.
  • the colorant being a dye or pigment may be soluble or dispersable in the polymeric resin binder.
  • the colorant is used preferably in an amount of at least 2 % by weight with respect to the total toner composition, more preferably in an amount in the range of 5 to 15 % by weight.
  • Examples of carbon black and analogous forms therefor are lamp black, channel black, and furnace black e.g. SPEZIALSCHWARZ IV (trade-name of Degussa Frankfurt/M, W.Germany) and VULCAN XC 72 and CABOT REGAL 400 (trade-names of Cabot Corp. High Street 125, Boston, U.S.A.).
  • SPEZIALSCHWARZ IV trade-name of Degussa Frankfurt/M, W.Germany
  • VULCAN XC 72 and CABOT REGAL 400 trade-names of Cabot Corp. High Street 125, Boston, U.S.A.
  • Toners for the production of colour images may contain organic dyes or pigments of the group of phthalocyanine dyes, quinacridone dyes, triaryl methane dyes, sulphur dyes, acridine dyes, azo dyes and fluoresceine dyes.
  • organic dyes or pigments of the group of phthalocyanine dyes, quinacridone dyes, triaryl methane dyes, sulphur dyes, acridine dyes, azo dyes and fluoresceine dyes can be found in "Organic Chemistry” by Paul Karrer, Elsevier Publishing Company, Inc. New York (1950).
  • Typical inorganic pigments include black iron(III) oxide, copper(II) oxide and chromium(III) oxide powder, milori blue, ultramarine cobalt blue and barium permanganate.
  • a magnetic or magnetizable material may be added during the toner production.
  • Magnetic materials suitable for said use are magnetic or magnetizable metals including iron, cobalt, nickel and various magnetizable oxides including (hematite) Fe2O3, (magnetite) Fe3O4, CrO2 and magnetic ferrites, e.g. these derived from zinc, cadmium, barium and manganese.
  • various magnetic alloys e.g. permalloys and alloys of cobalt-phosphors, cobalt-nickel and the like or mixtures of any of these. Good results can be obtained with about 30 % to about 80 % by weight of magnetic material with respect to the resin binder of the toner.
  • the colorant and optionally magnetic material may be added in finely divided state to the mixture of molten resin binder while stirring until a mixture of homogeneously dispersed or dissolved material in the resin melt is obtained.
  • the mixing temperature is e.g. in the range of 100 to 150°C.
  • the solid mass obtained is crushed and ground e.g. in a hammer mill followed by a jet-mill to an average particle size of 1 to 50 ⁇ m.
  • the fraction having a particle size between 3-30 ⁇ m separated e.g. by air sifter is used.
  • the resulting powder may not be tacky below 50°C.
  • the maximum development density attainable with toner particles of a given size is determined by the charge/toner particle mass ratio, which is determined substantially by the triboelectric charge obtained by friction-contact with the carrier particles.
  • the toner according to the present invention is applied in a carrier-toner mixture wherein the toner acquires a positive charge by frictional contact with the carrier.
  • the carrier-toner mixture is preferably applied to the surface carrying a latent electrostatic image by cascade-, or magnetic brush development which techniques are described in detail by Thomas L. Thourson in his article "Xerographic Development Processes : A Review", IEEE Transactions on Electron Devices, Vol. ED-19, No. 4, April 1972 p. 497-504.
  • Suitable carrier particles for use in cascade and for magnetic brush development are described in GB-P 1,438,110.
  • the carrier particles are preferably at least 3 times larger in size than the toner particles.
  • their particle size is preferably in the range of 50 to 1000 ⁇ m.
  • the carrier particles may be made of iron or steel optionally provided with an oxide skin.
  • Other types of carriers are on the basis of magnetic material such as ferrites or magnetite finely dispersed in a resin binder material, so-called composite type carriers, examples of which are given in US-P 4,600,675 and published European patent application 0 289 663.
  • Iron or steel carrier beads may be subjected to special pretreatments to enhance the triboelectric charging of the toner. Suitable coating-treatments of carrier beads are described e.g. in said last mentioned GB-P 1,438,110.
  • the carrier particles are magnetically attractable.
  • Particularly suited are the iron bead carrier particles according to United States Patent Specification 2,786,440, which particles have been washed free from grease and other impurities and have a diameter of 1.52x10 ⁇ 1 to 2.03x10 ⁇ 1 mm.
  • the toner particles are mixed with iron carrier beads of a diameter in the range of 50 to 200 ⁇ m having a thin iron oxide skin.
  • These carrier beads have almost a spherical shape and are prepared e.g. by a process as described in GB-P 1,174,571.
  • the developer composition may for example contain 1 to 5 parts by weight of toner particles per 100 parts by weight of carrier particles.
  • the flowing properties of the developer are improved by mixing the toner particles with a flow improving substance such as colloidal silica particles and/or microbeads of a fluorinated polymer.
  • the flow improving substance is used e.g. in an amount of 0.05 to 1 % by weight with respect to the toner.
  • colloidal silica has been described for that purpose in the GB-P 1,438,110. Particularly useful is AEROSIL 300 [trade mark of Degussa, Frankfurt (M) W.Germany] for colloidal silica having a specific surface area of 300 sq.m/g. The specific surface area can be measured by a method described by Nelsen and Eggertsen in "Determination of Surface Area Adsorption Measurements by Continuous Flow Method", Analytical Chemistry, Vol. 30, No. 8 (1958) 1387-1390.
  • Suitable fluorinated polymer beads for improving the flowing properties of the toner as well as of the carrier particles are described in the United States Patent Specification 4,187,329.
  • a preferred fluorinated polymer for said use is poly(tetrafluoroethylene) having a particle size of 3 to 4 ⁇ m and melting point of 325-329°C.
  • Such poly(tetrafluoroethylene) is sold under the trade name HOSTAFLON TF-VP-9202 by Farbwerke Hoechst A.G. W.Germany.
  • An other fluorinated polymer useful for that purpose is polyvinylidene fluoride having an average particle size of 5 ⁇ m sold under the trade name KYNAR RESIN 301 by Pennwalt Corp. - Plastic div. England.
  • the colloidal silica and/or said fluorinated polymer particles are mixed preferably with the toner in a proportion of 0.15 % to 0.075 % by weight.
  • the toner becomes thereby non-tacky and obtains a reduced tendency to form a film on the xerographic plates or drums e.g. having a vapour-deposited coating of a photoconductive Se-As alloy on a conductive substrate e.g. aluminium.
  • a pseudo toner was prepared without colouring agent to check whether or not the incorporated charge controlling agent yielded a clear mixture on melting with the elected resin binder.
  • Two comparable colourless pseudo toners were prepared by mixing in the melt 5 parts of a furtheron identified charge controlling substance with 95 parts of copolymer of (styrene-n-butylmethacrylate)(65/35) having a ring and ball softening point : 123 °C which copolymer serves as thermoplastic binder.
  • the mixture was melt-kneaded at 130°C for 30 minutes. Thereupon the mixture was cooled down to room temperature, crushed and then pulverised by milling in a jet mill.
  • An electroscopic developer was prepared by mixing 3% of the separated toner particles with iron bead carrier particles having an iron oxide skin and average grain size of 80 ⁇ m.
  • the triboelectric charging of the resulting powder mixture was realized by a 30 minutes agitation in a metal cylinder having a diameter of 6 cm, being filled for approximately 30% by volume with said mixture and revolving at a speed of 60 rpm.
  • the separation of the toner from the carrier particles was realized in a commercially available blow-off type powder charge measuring device.
  • the charge density was calculated, and expressed in C/cm 2.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Developing Agents For Electrophotography (AREA)

Claims (11)

  1. Eine Zusammensetzung elektrostatisch anziehbarer Tonerteilchen für den Gebrauch in der Entwicklung latenter, elektrostatischer Bilder, wobei diese Tonerteilchen in Anwesenheit von Trägerteilchen durch triboelektrische Kontaktelektrisierung eine positive Ladung erwerben, wobei diese Zusammensetzung ein oder mehrere thermoplastische Harze als Bindemittel zusammen mit einem Farbstoff und einem farblosen Positivladungsregler enthält, dadurch gekennzeichnet, daß der farblose Ladungsregler in seiner Molekularstruktur zumindest eine polyalkylsubstituierte Piperidingruppe und eine sterisch behinderte Phenolgruppe enthält und die folgende, allgemeine Formel (A) hat:
    Figure imgb0014
     in der bedeuten:
    R¹ ein Wasserstofatom oder eine Alkylgruppe mit 1 bis 4 Kohlenstoffatomen,
    R² eine Alkylgruppe oder eine Hydroxyalkylgruppe, je mit 1 bis 12 Kohlenstoffatomen, eine Alkenylgruppe oder eine Alkynylgruppe, je mit 3 oder 4 Kohlenstoffatomen, oder eine Aralkylgruppe,
    R³ ein Wasserstoffatom oder eine Methylgruppe,
    R⁴ und R⁵ je eine Alkylgruppe mit 1 bis 5 Kohlenstoffatomen oder eine Cycloalkylgruppe mit 5 bis 8 Kohlenstoffatomen,
    X ein Sauerstoffatom oder eine NH-Gruppe,
    Y ein Wasserstoffatom, eine Alkylgruppe mit 1 bis 12 Kohlenstoffatomen oder eine -CnHnCOOR⁷-Gruppe, in der n 0 oder eine ganze Zahl von 1 bis 10 ist und R⁷ ein Wasserstoffatom ist, eine Alkylgruppe mit 1 bis 18 Kohlenstoffatomen, oder Y bedeutet einen Substituenten der nachstehenden Formel:
    Figure imgb0015
     in der:
    R¹ und R² die gleiche Bedeutung wie oben haben, oder
    Y ein Substituent der nachstehenden Formel ist:
    Figure imgb0016
     in der:
    R¹ und R² die gleiche Bedeutung wie oben haben, und R⁹ ein Wasserstoffatom oder eine Alkylgruppe mit 1 bis 4 Kohlenstoffatomen ist,
    m 1 oder 2 ist, und
    p 0 oder 1 ist.
  2. Eine Zusammensetzung elektrostatisch anziehbarer Tonerteilchen gemäß Anspruch 1, dadurch gekennzeichnet, daß der farblose Ladungsregler in einem Gehalt zwischen 0,5 und 5 Gew.-% mit Bezug auf die gesamte Tonerzusammensetzung verwendet wird.
  3. Eine Zusammensetzung elektrostatisch anziehbarer Tonerteilchen gemäß Anspruch 1 oder 2, dadurch gekennzeichnet, daß der farblose Ladungsregler aufgelöst oder dispergiert ist in einem thermoplastischen Bindemittel, das ein Homo- oder Copolymeres von Styrol ist, in dem der Styrolgehalt zumindest 50 Mol-% beträgt.
  4. Eine Zusammensetzung elektrostatisch anziehbarer Tonerteilchen gemäß Anspruch 3, dadurch gekennzeichnet, daß das Copolymere ein Styrol-Methylacrylat-Copolymeres, ein Styrol-Ethylacrylat-Copolymeres, ein Styrol-n-Butylacrylat-Copolymeres, ein Styrol-n-Octylacrylat-Copolymeres, ein Styrol-Methylmethacrylat-Copolymeres, ein Styrol-EthylmethacrylatCopolymeres, ein Styrol-n-Butylmethacrylat-Copolymeres, ein Styrol-Isobutylmethacrylat-Copolymeres, ein Styrol-n-Octylmethacrylat-Copolymeres, ein Styrol-Heptadecylmethacrylat-Copolymeres, ein Styrol-ButadienCopolymeres oder ein Copolymeres von Styrol ist, das bis zu 25 Gew.-% Monomereinheiten, die eine Dialkylaminogruppe enthalten, enthält.
  5. Eine Zusammensetzung elektrostatisch anziehbarer Tonerteilchen gemäß irgendwelchem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß der Farbstoff Gasruß ist.
  6. Eine Zusammensetzung elektrostatisch anziehbarer Tonerteilchen gemäß irgendwelchem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß der Farbstoff ein organischer Farbstoff oder ein organisches Pigment aus der Gruppe von Phthalocyaninfarbstoffen, Chinacridonfarbstoffen, Triarylmethanfarbstoffen, Schwefelfarbstoffen, Acridinfarbstoffen, Azofarbstoffen und Fluoreszeinfarbstoffen ist.
  7. Eine Zusammensetzung elektrostatisch anziehbarer Tonerteilchen gemäß irgendwelchem der vorstehenden Ansprüche, dadurch gekennzeichnet, daß sie weiter ein magnetisches oder magnetisierbares Material umfaßt.
  8. Eine Zusammensetzung elektrostatisch anziehbarer Tonerteilchen gemäß irgendwelchem der vorstehenden Ansprüche, dadurch gekennzeichnet, daß das basische Ringstickstoffatom der Piperidingruppe in den Verbindungen gemäß der allgemeinen Formel (A) in Salzform umgewandelt worden ist.
  9. Eine Entwicklerzusammensetzung, die Tonerteilchen umfaßt, die der Zusammensetzung gemäß irgendwelchem der vorstehenden Ansprüche entsprechen und mit Trägerteilchen gemischt sind, die für den Gebrauch in der Kaskaden- oder Magnetbürstenentwicklung latenter, elektrostatischer Ladungsbilder geeignet sind.
  10. Eine Entwicklerzusammensetzung gemäß Anspruch 9, dadurch gekennzeichnet, daß die Trägerteilchen zumindest dreimal größer sind als die Tonerteilchen und eine mittlere Korngröße zwischen 50 und 1000 µm haben.
  11. Eine Entwicklerzusammensetzung gemäß Anspruch 9 oder 10, dadurch gekennzeichnet, daß die Trägerteilchen aus mit einer Oxidschicht versehenem Eisen oder Stahl hergestellt sind.
EP90200217A 1989-02-08 1990-01-30 Partikeltonermaterial Expired - Lifetime EP0382285B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP90200217A EP0382285B1 (de) 1989-02-08 1990-01-30 Partikeltonermaterial

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
EP89200290 1989-02-08
EP89200290 1989-02-08
EP90200217A EP0382285B1 (de) 1989-02-08 1990-01-30 Partikeltonermaterial

Publications (2)

Publication Number Publication Date
EP0382285A1 EP0382285A1 (de) 1990-08-16
EP0382285B1 true EP0382285B1 (de) 1994-10-26

Family

ID=26120946

Family Applications (1)

Application Number Title Priority Date Filing Date
EP90200217A Expired - Lifetime EP0382285B1 (de) 1989-02-08 1990-01-30 Partikeltonermaterial

Country Status (1)

Country Link
EP (1) EP0382285B1 (de)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4416265A1 (de) * 1994-05-07 1995-11-09 Basf Ag Elektrostatische Toner, enthaltend Phenacylverbindungen

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4268593A (en) * 1978-11-06 1981-05-19 Ciba-Geigy Ag Recording material for color photography

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2032286T3 (es) * 1986-12-01 1993-02-01 Kao Corporation Pigmento en polvo para el revelado de imagenes cargadas electrostaticamente.

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4268593A (en) * 1978-11-06 1981-05-19 Ciba-Geigy Ag Recording material for color photography

Also Published As

Publication number Publication date
EP0382285A1 (de) 1990-08-16

Similar Documents

Publication Publication Date Title
US4323634A (en) Electrographic toner and developer composition containing quaternary ammonium salt charge control agent
US4684596A (en) Electrographic toner and developer composition containing quaternary ammonium salt charge-control agent
US3893935A (en) Electrographic toner and developer composition
CA1148403A (en) Toners containing alkyl pyridinium compounds and their hydrates
US3944493A (en) Electrographic toner and developer composition
US4221856A (en) Electrographic toner containing resin-compatible quaternary ammonium compound
US4299898A (en) Positively charged toners containing quaternary ammonium salts attached to acrylate polymers
GB1588033A (en) Particulate electrographic toner composition
US4988600A (en) Particulate electrophotographic toner material
US6221550B1 (en) 4H-pyran charge control agents for electrostatographic toners and developers
US5188919A (en) Particulate toner material containing charge controlling compound
US5482807A (en) Positively-chargeable toner
US5085965A (en) Negative toner for developing latent electrostatic images
JPS6363054A (ja) 単一成分レッド現像組成物
US4304830A (en) Toner additives
US5013628A (en) Particulate toner material with charge control agent
JPH08500196A (ja) 静電写真に使用するための正に帯電されたトナー
EP0382285B1 (de) Partikeltonermaterial
US5232809A (en) Toner for electrophotography
US4812380A (en) Electrostatographic toners and developers containing new charge-control agents
US5232808A (en) Electrostatographic toner and developer containing a fluorinated β-diketone metal complex charge-control agent
US4256824A (en) Method using positively charged electrophotographic toner containing amido dialkyl hydroxy ammonium compound
EP0615168B1 (de) Elektrostatischer bildentwickelnder Toner
US5382491A (en) Toner composition
US4812382A (en) Electrostatographic toners and developers containing new charge-control agents

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): BE DE FR GB

17P Request for examination filed

Effective date: 19901117

17Q First examination report despatched

Effective date: 19920702

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): BE DE FR GB

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: BE

Effective date: 19941026

REF Corresponds to:

Ref document number: 69013529

Country of ref document: DE

Date of ref document: 19941201

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: BE

Payment date: 19941219

Year of fee payment: 6

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: GB

Ref legal event code: 746

Effective date: 19970207

REG Reference to a national code

Ref country code: FR

Ref legal event code: D6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20001213

Year of fee payment: 12

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20001228

Year of fee payment: 12

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20010111

Year of fee payment: 12

REG Reference to a national code

Ref country code: GB

Ref legal event code: 732E

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20020130

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20020801

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20020130

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20020930

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST