EP0227874B1 - Toner pour le développement d'images électrostatiques latentes - Google Patents

Toner pour le développement d'images électrostatiques latentes Download PDF

Info

Publication number
EP0227874B1
EP0227874B1 EP19860100043 EP86100043A EP0227874B1 EP 0227874 B1 EP0227874 B1 EP 0227874B1 EP 19860100043 EP19860100043 EP 19860100043 EP 86100043 A EP86100043 A EP 86100043A EP 0227874 B1 EP0227874 B1 EP 0227874B1
Authority
EP
European Patent Office
Prior art keywords
toner
acid
resin
parts
zinc
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
EP19860100043
Other languages
German (de)
English (en)
Other versions
EP0227874A1 (fr
Inventor
Yoji Kawagishi
Shinichi Narita
Takashi Kiriu
Kenji Uomoto
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.)
Orient Chemical Industries Ltd
Original Assignee
Orient Chemical Industries Ltd
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 Orient Chemical Industries Ltd filed Critical Orient Chemical Industries Ltd
Priority to AT86100043T priority Critical patent/ATE57025T1/de
Priority to DE8686100043T priority patent/DE3674562D1/de
Publication of EP0227874A1 publication Critical patent/EP0227874A1/fr
Application granted granted Critical
Publication of EP0227874B1 publication Critical patent/EP0227874B1/fr
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
    • G03G9/097—Plasticisers; Charge controlling agents
    • G03G9/09783—Organo-metallic compounds

Definitions

  • the present invention relates to a negatively chargeable toner of the dry type for developing electrostatic latent images in electrophotography, electrostatic recording, electrostatic printing as claimed in Claim 1.
  • Electrostatic latent images can be developed into visible images with a toner which is caused to adhere to the image by electrostatic attraction.
  • a toner which is caused to adhere to the image by electrostatic attraction.
  • powder developers are widely used for developing electrostatic latent images.
  • the powder developers are divided generally into two types: two-component developers comprising a toner having a mean particle size of 15 J.lm and a carrier of finely divided iron or ferrite mixed with the toner and 100 to 200 ⁇ m in particle size, the toner being composed of a natural resin or synthetic resin and a coloring agent, charge control agent, fluidizing agent, etc. dispersed in the resin; and one-component developers comprising a natural resin or synthetic resin, and a coloring agent, charge control agent, fluidizing agent and magnetic material which are dispersed in the resin.
  • the toner is triboelectrically charged by the carrier and deposited on electrostatic images for development.
  • the one-component developers heretofore known include toners which are chargeable by friction with a brush- or plate-like friction member serving the function of the carrier as a substitute therefor. Also made known in recent years is a toner which is chargeable by friction with a finely divided magnetic material which is maintained in a dispersed state. These developing toners are held positively or negatively charged in accordance with the polarity of the electrostatic latent image to be developed.
  • these dyes and pigments as charge control agents are complex in structure and low in stability. They are susceptible to decomposition or degradation to lose charge control properties, owing for example to mechanical friction and impact, changes of temperature and humidity, electrical impact, irradiation with light, etc. Further one of their substantial defects is that these agents are colored substances and are therefore in conflict with the requirement that a colorless or substantially colorless charge control agent should be used for a toner having a particular color.
  • the document DE-A 3 144 017 describes a toner containing a resin and, as a charge control agent, a Cr, Co or Fe complex of a substituted salicylic acid and of another aromatic hydroxycarboxylic acid having or not having a substituent.
  • the metal complex is reported to have good compatibility with the resin component, to be substantially colorless, and to impart outstanding durability to the toner.
  • the document DE-A 3 329 252 describes a toner containing an amorphous polyester having an acid number of 10 to 100 and being obtained by reacting an etherified diphenol with a benzene dicarboxylic acid or a mixture of benzene dicarboxylic acids, and a salicylic acid metal complex.
  • the diphenol is either propoxylated or propoxylated and ethoxylated, wherein the content of propoxy groups is not less than 50 mole percent of the total content of the propoxy and ethoxy groups, and the benzene dicarboxylic acid or the mixture of benzene dicarboxylic acids contains up to 40 mole percent of a tribasic or higher-basic aromatic carboxylic acid.
  • the metal complex is reported to react with and cross-link the polyester to improve the viscosity at melt and to prevent adhering of the toner to hot rollers during a fixing process.
  • charge control agents such as metal-containing dyes and Nigrosin is described as being optional.
  • the metal complex may be selected from zinc salicylate, chromium salicylate, manganese salicylate, nickel salicylate, cobalt salicylate, cobalt-t-butyl salicylate, chromium-3,5-di-t-butyl salicylate and nickel-3,5-di-t-butyl salicylate.
  • the object of the present invention is to provide a toner containing a resin and, as a charge control agent capable of giving negative charges to the toner, a compound which remains thermally stable up to a temperature permitting thorough melting and kneading and which is colorless.
  • the present invention provides a toner for developing electrostatic latent images, the toner containing a resin and, as a charge control agent, a metal complex of an aromatic hydroxycarboxylic acid having or not having a substituent.
  • the toner is characterized in that the metal complex is a zinc complex, toners being excluded wherein the zinc complex is zinc salicylate and the resin is the specific amorphous polyester described in the document DE-A 3 329 252.
  • Examples of useful aromatic hydroxycarboxylic acids which may have a substituent and which are capable of forming zinc complex compounds are alkyl(C4-C g )salicylic acids, 3,5-dialkyl(C 4 -Cs)salicylic acids, 2-hydroxy-3-naphthoic acid, alkyl(C 4 -Cs)-2-hydroxy-3-naphthoic acids, 5,6,7,8-tetrahalogen-2-hydroxy-3-naphthoic acids, etc.
  • the zinc complex compound of the present invention can be prepared by dissolving a suitable hydroxycarboxylic acid in water with addition of a sufficient amount of alkali, adding to the solution a metallic zinc giving agent in the agent-to-acid mole ratio of 1:2, heating the mixture, adjusting the pH of the reaction mixture, filtering off the resulting precipitate, thoroughly wahing the precipitate with water and drying the precipitate.
  • the product is represented by the formula wherein A and A ' are the residue of an aromatic hydroxycarboxylic acid which may have a substituent, and M is a counter ion.
  • the counter ion can be changed by changing the condition for the aftertreatment of the reaction mixture. For example, when the reaction mixture is adjuted to a pH of up to 3, then filtered and thereafter washed until the pH becomes about 6 to about 7, the counter ion is hydrogen ion. If the pH is adjusted to neutrality to alkalinity with an alkali, alkali metal ion is obtained. Further if the mixture is treated with hydrochlorides of various amines, various ammonium salts are obtained.
  • the complex compound of the formula (I) is incorporated into a toner generally in an amount of 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, per 100 parts by weight of the component resin of the toner.
  • the toner of the present invention is prepared by admixing the complex compound of the formula (I) with at least one of the resins heretofore known for use in toners, such as styrene resin, styrene-acrylic resin, styrene-butadiene resin, epoxy resin, polyester resin, paraffin wax and the like.
  • the resin to be used is determined in view of adhering properties, preservability, free-flowability, amenability to pulverization, etc.
  • dyes and pigments are usable as coloring agents, especially suitable as coloring agents for toners for color copying are, for example, Benzidine Yellow, quinacridone, Copper Phthalocyanine Blue, Copper Phthalocyanine Green, etc.
  • the toner is usually mixed with a carrier to provide a two-component developer, it is of course usable as a one-component developer.
  • a 44.5 g (0.18 mole) quantity of 3,5-di-tert-butylsalicylic acid was completely dissolved in 400 g of 2% aqueous solution of caustic soda, and the solution was heated to about 70 ° C.
  • Polyester resin (ATR-2010, product of Kao Soap Co., Ltd.) 100 parts Blue dye (Valifast Blue 2606, product of Orient Kagaku Kogyo Co., Ltd.) 2 parts Blue pigment (Copper Phthalocyanine) 4 parts Compound (1) 1 part
  • the above ingredients were premixed uniformly by a ball mill to obtain a premix, which was kneaded in a molten state by heat rolls, then cooled, thereafter crushed by a vibrating mill and further pulverized by an air jet mill.
  • the fine powder obtained was screened to obtain a blue toner 10 to 20 ⁇ m in particle size.
  • the amount of initial blow-off charge on the developer was -28.3 ⁇ c/g.
  • sharp blue toner images were obtained free from fog. Even after the toner was used for continuously making 50,000 copies, no reduction was observed in the quality of copies.
  • Epoxy resin (Epikote 1004, product of Shell Chemical Co. Ltd.) 100 parts Carbon black 6 parts Compound (2) 2 parts
  • the toner obtained Three parts of the toner obtained were admixed with 97 parts of a carrier of finely divided iron to prepare a developer.
  • the amount of initial blow-off charge on the developer was -24.1 ⁇ c/g.
  • sharp black toner images were obtained free from any fog.
  • the toner exhibited no reduction in the quality of copies even after continuously making 50,000 copies.
  • the toner obtained Three parts of the toner obtained were admixed with 97 parts of a carrier of finely divided iron to prepare a developer.
  • the amount of initial blow-off charge on the developer was -25.2 l icfg.
  • the developer When used for copying in the same manner as in Example 1, the developer produced toner images free from any fog and outstanding in reproducibility of thin lines.
  • the toner exhibited no reduction in the quality of copies even after continuously making 50,000 copies.
  • Styrene-n-butyl methacrylate copolymer resin 65/35) 100 parts Red dye (Valifast Pink 2310, product of Orient Kagaku Kogyo Co., Ltd.) 8 parts Compound (2) 2 parts
  • a red toner was prepared from the above ingredients in the same manner as in Example 1. Three parts of the toner obtained were admixed with 97 parts of a carrier of finely divided iron to obtain a developer. The amount of initial blow-off charge on the developer was -22.9 I!c/g. When used for copying in the same manner as in Example 1, the developer produced sharp red toner images free from any fog. The toner exhibited no reduction in the quality of copies even after continuously making 50,000 copies.
  • a yellow toner was prepared from the above ingredients in the same manner as in Example 1.
  • the toner obtained Three parts of the toner obtained were admixed with 97 parts of a carrier of finely divided iron to obtain a developer.
  • the amount of initial blow-off charge on the developer was -21.8 ⁇ c/g.
  • the developer When used for copying in the same manner as in Example 1, the developer produced sharp yellow toner images free from any fog.
  • the toner exhibited no reduction in the quality of copies even after continuously making 50,000 copies.

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

Claims (3)

1. Un procédé de préparation d'un toner pour le développement d'images électrostatiques latentes par mélange d'une résine, d'un agent colorant et, en tant qu'agent de commande de charge un complexe métallique d'un acide hydroxycarboxylique aromatique ayant ou n'ayant pas un substituant, caractérisé par l'utilisation d'un complexe de zinc en tant que complexe métallique, le procédé, à l'exclusion de celui dans le complexe de zinc et la résine utilisée est un polyester amorphe présentant un indice d'acidité de 10 à 100, étant obtenu par réaction d'un diphénol éthérifié avec un acide dicarboxylique benzène ou un mélange d'acides dicarboxyliques benzène, le diphénol étant soit propoxylé, soit propoxylé et éthoxylé, et la teneur en groupes propoxy n'étant pas inférieure à 50 moles pour-cents de la teneur totale en groupes propoxy et éthoxy, et l'acide dicarboxylique benzène ou le mélange d'acides dicarboxyliques benzène contient jusqu'à 40 moles pour-cents d'un acide carboxylique aromatique tribasique ou plus que tribasique.
2. Un procédé selon la revendication 1, dans lequel le complexe de zinc utilisé est un acide salicylique alkyle (C4 à Cs), un acide salicylique 3,5-dialkyle (C4 à Cs), un acide 2-hydroxy-3-naphtoïque, un acide alkyle (C4 à C9)-2-hydroxy-3-naphtoïque ou un acide 5,6,7,8-tétrahaiogène-2-hydroxy-3-naphtoïque.
3. Un procédé selon la revendication 1, dans lequel on utilise de 0,5 à 5 parties en poids du composé complexe de zinc pour 100 parties en poids du constituant résine du toner.
EP19860100043 1984-09-12 1986-01-03 Toner pour le développement d'images électrostatiques latentes Expired - Lifetime EP0227874B1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AT86100043T ATE57025T1 (de) 1986-01-03 1986-01-03 Toner fuer die entwicklung elektrostatischer latenter bilder.
DE8686100043T DE3674562D1 (de) 1986-01-03 1986-01-03 Toner fuer die entwicklung elektrostatischer latenter bilder.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP59191117A JPS6169073A (ja) 1984-09-12 1984-09-12 静電荷像現像用トナ−

Publications (2)

Publication Number Publication Date
EP0227874A1 EP0227874A1 (fr) 1987-07-08
EP0227874B1 true EP0227874B1 (fr) 1990-09-26

Family

ID=16269146

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19860100043 Expired - Lifetime EP0227874B1 (fr) 1984-09-12 1986-01-03 Toner pour le développement d'images électrostatiques latentes

Country Status (2)

Country Link
EP (1) EP0227874B1 (fr)
JP (1) JPS6169073A (fr)

Families Citing this family (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4762763A (en) * 1985-12-19 1988-08-09 Ricoh Co., Ltd. Toner for developing electrostatic latent image
JP2572756B2 (ja) * 1986-11-07 1997-01-16 三菱化学株式会社 静電荷像現像用トナ−
US4985328A (en) * 1988-09-22 1991-01-15 Hitachi Chemical Co., Ltd. Dry toner, dry developer and process for forming electrophotographic images
US5153090A (en) * 1990-06-28 1992-10-06 Commtech International Management Corporation Charge directors for use in electrophotographic compositions and processes
JPH03185457A (ja) * 1989-12-15 1991-08-13 Konica Corp カラートナー
JP2609359B2 (ja) * 1990-11-28 1997-05-14 三田工業株式会社 負帯電用電子写真用トナー
JP2609356B2 (ja) * 1990-11-28 1997-05-14 三田工業株式会社 負帯電性電子写真用トナー
JP2609357B2 (ja) * 1990-11-28 1997-05-14 三田工業株式会社 負帯電用電子写真用トナー
AU8897391A (en) * 1990-12-12 1992-06-18 Mitsubishi Kasei Corporation Electrostatic image-developing toner
GB9306456D0 (en) * 1993-03-29 1993-05-19 Zeneca Ltd Composition and use
SG73592A1 (en) 1997-12-05 2000-06-20 Canon Kk Toner having negative triboelectric chargeability and developing method
DE69928159T2 (de) 1998-04-10 2006-07-20 Canon K.K. Zweikomponenten-Entwickler und Bilderzeugungsverfahren
DE69929552T2 (de) 1998-05-26 2007-01-11 Canon K.K. Toner mit negativer triboelektrischer Aufladbarkeit und Bildherstellungsverfahren
EP1383011B1 (fr) 2002-07-19 2005-04-06 Ricoh Company, Ltd. Toner comprenant agent de contrôle de charge organométallique à base de zirconium et méthode de formation d'images
JP5096931B2 (ja) 2006-01-23 2012-12-12 保土谷化学工業株式会社 電子写真用感光体
WO2007111346A1 (fr) 2006-03-29 2007-10-04 Hodogaya Chemical Co., Ltd. Melange de sulfures de phenols cycliques et agent de regulation de charge ou toner l'utilisant
CN101466697B (zh) 2006-04-13 2013-05-15 保土谷化学工业株式会社 氧化型混合环状苯酚硫化物、使用其的电荷控制剂及调色剂
WO2010035561A1 (fr) * 2008-09-29 2010-04-01 日本碍子株式会社 Matériau adsorbeur de gaz, précurseur du matériau adsorbeur de gaz et procédé destiné à produire un matériau adsorbeur de gaz
EP2541329A4 (fr) 2010-02-26 2014-05-21 Hodogaya Chemical Co Ltd Agent de contrôle de charge et toner l'utilisant
CN103109239A (zh) 2010-09-13 2013-05-15 保土谷化学工业株式会社 电荷控制剂以及使用了该电荷控制剂的调色剂
US8900785B2 (en) 2010-09-14 2014-12-02 Hodogaya Chemical Co., Ltd. Charge control agent and toner using the same
KR20130099913A (ko) 2010-09-15 2013-09-06 호도가야 가가쿠 고교 가부시키가이샤 전하 제어제 및 그것을 사용한 토너
JP5893571B2 (ja) 2011-01-27 2016-03-23 保土谷化学工業株式会社 電荷制御剤及びそれを用いたトナー
JP2012177827A (ja) 2011-02-28 2012-09-13 Ricoh Co Ltd トナー、このトナーを用いたフルカラー画像形成方法及びフルカラー画像形成装置
US9835965B2 (en) 2013-09-24 2017-12-05 Hodogaya Chemical Co., Ltd. Charge control agent and toner using same
EP3352020B1 (fr) 2015-09-17 2021-06-16 Hodogaya Chemical Co., Ltd. Agent de régulation de toner et de charge utilisant un dérivé de pyrazolone ou un sel du dérivé

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS53127726A (en) * 1977-04-13 1978-11-08 Canon Inc Electrostatic image developing toner
JPS5779964A (en) * 1980-11-06 1982-05-19 Canon Inc Developing method
JPS5841508B2 (ja) * 1980-12-22 1983-09-12 オリヱント化学工業株式会社 静電荷像現像用トナ−
JPS5929255A (ja) * 1982-08-12 1984-02-16 Canon Inc 静電荷現像用トナ−
JPS5979256A (ja) * 1982-10-29 1984-05-08 Ricoh Co Ltd 静電潜像現像用トナ−
JPS5988745A (ja) * 1982-11-15 1984-05-22 Hodogaya Chem Co Ltd 電子写真用トナ−

Also Published As

Publication number Publication date
JPH0260183B2 (fr) 1990-12-14
JPS6169073A (ja) 1986-04-09
EP0227874A1 (fr) 1987-07-08

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