JPH0357473B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a novel dry negatively charged toner for developing electrostatic latent images in electrophotography, electrostatic recording, electrostatic printing, and the like. [Prior Art] Originally, an electrostatic latent image can be developed and visualized by adhering toner using its electrostatic attraction, but as a developer for this electrostatic latent image,
In addition to liquid developers, powder developers are widely used. This powder developer consists of a fine toner with an average particle size of 15 μm, which is made by dispersing a colorant, a charge control agent, a fluidizing agent, etc. in natural or synthetic resin, and a carrier such as iron powder or ferrite powder with a diameter of 100 to 200 μm. Two-component developers consisting of mixtures and one-component developers consisting only of fine toner particles with an average particle size of 15 μm, which are made by dispersing colorants, charge control agents, fluidizing agents, magnetic materials, etc. in natural or synthetic resins. Can be separated. A two-component developer achieves development by attaching charged toner to an electrostatic latent image through friction with a carrier, and a one-component developer uses a similar type of toner instead of a carrier. Toner is known to be charged by friction with a functional brush-like or plate-like friction member, and recently, toner has been developed to keep magnetic fine powder in a dispersed state and to prevent mutual friction with the magnetic fine powder. Toners that are thus loaded are known. Therefore, these developing toners maintain a positive or negative charge depending on the polarity of the electrostatic latent image to be developed. In order to make the toner retain this charge, it has been proposed to utilize the triboelectricity of resin, which is the main component of the toner, but this method requires that the toner has a small chargeability and a solid surface resistance value of Because of the large size, the resulting image tends to be foggy and unclear. Therefore, in order to impart the desired triboelectric charging properties to the toner, dyes, pigments, and even charge control agents that impart a charge are added to the toner. , when imparting a positive charge to toner,
There are nigrosine-based oil-soluble dyes as shown in Japanese Patent Publication No. 41-2427, etc., and when imparting a negative charge, there are There are metal-containing complex salt dyes such as those shown in Publication No. 26478 and the like. However, the charge control agents described in these publications have (1) a small charge amount per unit (1251μC/
(2) low bulk (3.0cc/gr or less), and (3) poor crushability (more than 10% remains at 350mesh). As a result, images tend to fog and become unclear due to insufficient dispersion with the resin, and in the case of a two-component system, carrier contamination is significant. [Problems to be Solved by the Invention] In view of the above-mentioned drawbacks of conventional charge control agents, the present invention uses a titanium metal complex compound as a charge control agent, which has an excellent charge amount, is high in bulk, and has excellent pulverizability. It is an object of the present invention to provide a toner for electrostatic charge development, thereby solving the problems in the field. [Means for solving the problems] The present invention is based on the following general formula [In the formula, R ₁ and R ₂ represent hydrogen, a nitro group, a halogen, a sulfonamide group, or an alkyl group (C ₁ to _{C 6} ), and R ₁ and R ₂ may be the same or different. A is a pyrazolone derivative residue that may have a substituent,

[expression] or

[Formula] [In the formula, R ₃ represents hydrogen, an alkyl group (C ₁ to C ₈ ), a carboxyl group, or a carbamoyl group which may have an alkyl group or an aromatic substituent. ]. ] A toner for developing an electrostatic image, characterized by containing a titanium metal complex compound represented by the following. [Example] The titanium metal complex compound in the present invention is prepared by treating a metallizable azo compound with a titanizing agent by a known method, and then diluting with water containing acid or mineral acid to precipitate the compound, if necessary. Obtained by straining and filtering. Examples of the diazo component used to obtain the metallizable azo compound in the present invention include 2-aminophenol, 3-chloro-2-aminophenol, 4-chloro-2-aminophenol, 5-aminophenol,
Bromo-2-aminophenol, 3,5-dichloro-2-aminophenol, 5-nitro-2-aminophenol, 4-nitro-2-aminophenol, 4,6-dinitro-2-aminophenol, 4-sulfone Amido-2-aminophenol and the like can be mentioned. Examples of coupling components used to obtain metallizable azo compounds include:
Phenol, p-alkyl (C ₁ - _{C 8} ) phenol, β-naphthol, 2-oxy-3-naphthoic acid, naphthol AS, alkyl (C ₁ - _{C 6} )-2
-oxy-3-naphthoic acid, 1-phenyl-3-
Methyl-5-pyrazolone, 1-(4'-sulfamidophenyl)-3-methyl-5-pyrazolone, 1
-phenyl-3-carboxy-5-pyrazolone and the like. As the titanium metallizing agent for treating the metallizable azo compound, organic or inorganic titanium compounds can be used, such as tetraisopropoxytitanium, tetra-n-butoxytitanium, titanium tetrachloride, and the like. Synthesis Example 18 parts of tetraisopropoxy titanium was dissolved in 80 parts of ethyl cellosolve and 40 parts of ethylene glycol mixed solvent, then 30 parts of a monoazo compound represented by the following formula was added, and the reaction was stirred at 115 to 120°C for 2 hours. I went to The reaction mixture was precipitated with 100 parts of water and 17 parts of concentrated hydrochloric acid, and the precipitate was collected by filtration, washed with water, and dried to obtain a fine black powder as shown in Compound Example (1) below. 31 parts of a titanium complex compound were obtained. Next, specific examples (1) to (6) of the metal complex compounds represented by the general formula [] of the present invention and their physical properties are described below, and for comparison, comparative compound examples (1) and (2) Added.

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[Table] The titanium metal complex compound used in the present invention has an excellent charge amount (more than |25|μC/gr) and a high bulk (4.0 cc /gr or more), and has excellent pulverization properties (5%
(below), it has the characteristic of extremely good dispersibility in toner resins. By the way,
The amount of the complex compound of general formula [] added to the toner component is preferably 0.1 to 10 parts by weight, particularly 0.3 to 5 parts by weight, based on 100 parts by weight of the resin. In addition to the complex compound represented by the above general formula [], the toner of the present invention includes a styrene resin, a styrene-acrylic resin, a styrene resin, a styrene-acrylic resin, Styrene-butadiene resin, epoxy resin, polyester resin,
It can be used alone or in combination of several types, such as paraffin wax. Further, as the coloring agent, many known dyes and pigments can be used. Further, the toner of the present invention may contain additives other than the above-mentioned toner resin and colorant, if necessary. Examples of the additive include Teflon,
Examples include lubricants such as zinc stearate, fluidity imparting agents such as colloidal silica, titanium oxide and aluminum oxide, anti-caking agents, conductivity imparting agents such as carbon black and tin oxide, and fixing aids such as low molecular weight polyethylene. The toner of the present invention is mixed with a carrier to provide a two-component developer, and any known carrier can be used. Also, when forming a developer as a one-component toner, it is possible to mix it with known magnetic powder (eg, magnetite, ferrite, etc.). Specific examples of the present invention will be explained below using specific examples. In addition, in Examples and Comparative Examples, parts by weight are abbreviated as parts. Example 1 Styrene-acrylic copolymer (manufactured by Sanyo Kasei Co., Ltd., Hymer SMB600)...100 parts Carbon black (manufactured by Mitsubishi Kasei Co., Ltd., #44)...7 parts Compound example (1)...1.2 parts The above mixture was uniformly mixed with a ball mill. Pre-mix,
Prepare premixes. The mixture was then melt-kneaded using hot rolls, cooled, coarsely ground using a vibrating mill, and further finely ground using a Labojet (manufactured by Nippon Neumatic Co., Ltd.). The obtained fine powder was classified to obtain a black toner having a particle size of 5 to 15 μm. 97 parts of iron powder carrier (manufactured by Nippon Tetsuko Co., Ltd., TEFV200/300) was mixed with 3 parts of the obtained toner.
A developer was prepared. The initial blow-off charge amount of this developer was -32.6 μC/gr. When we measured the amount of blow-off charge after copying 10,000 sheets using a copying machine equipped with a toner recycling device, -
It was very stable at 32.1μC/gr. When the image was copied using a commercially available copying machine (Serendrum), an image with good fine line reproducibility was obtained. Even after 10,000 continuous copies, this toner maintains
A good image was obtained with no change in image density (1.50 or more) and no toner fusion phenomenon (filming phenomenon) on the photoreceptor. Example 2 Polyester resin (manufactured by Kao Soap Co., Ltd., ATR-2010)
...100 parts carbon black (manufactured by Mitsubishi Kasei Co., Ltd., #44) ...4 parts blue dye (manufactured by Orient Chemical Co., Ltd., Valifast
Blue 2606)...1 part Compound Example (2)...1 part The above formulation was treated in the same manner as in Example 1 to prepare a toner. A developer was prepared by mixing 97 parts of iron powder carrier with 3 parts of the obtained toner. The initial blow-off charge amount of this developer was -30.6 μC/gr. When a toner image was formed using this developer using a commercially available copying machine, a clear image with no fog and good fine line reproducibility was obtained. Even after continuous copying of 100,000 sheets, stable copied images with no change were obtained. Example 3 In Example 1, 1.2 parts of Compound Example (3) was used in place of Compound Example (1), and the remaining points were as in Example 1.
A toner was prepared in the same manner. A developer was prepared by mixing 97 parts of iron powder carrier with 3 parts of the obtained toner. The initial blow-off charge amount of this developer was -30.7 μC/gr. When a toner image was formed using this developer using a commercially available copying machine, a clear image with no fog and good fine line reproducibility was obtained. Even after 10,000 continuous copies, stable copied images with no change were obtained. Example 4 Epoxy resin (manufactured by Ciel Chemical Co., Ltd., Epicoat
1004) 100 parts Carbon Black (manufactured by Mitsubishi Kasei Corporation, #44) 6 parts Compound Example (4) 1 part The above formulation was treated in the same manner as in Example 1 to prepare a black toner. A developer was prepared by mixing 97 parts of iron powder carrier with 3 parts of the obtained toner. The initial blow-off charge amount of this developer was -29.8 μC/gr. When a toner image was formed using this developer using a commercially available copying machine, a clear image with no fog and good fine line reproducibility was obtained. Even after 10,000 continuous copies, stable copied images with no change were obtained. Example 5 Styrene-2-ethylhexyl methacrylate copolymer resin (80/20)...50 parts magnetite (manufactured by Kanto Denka Co., Ltd., KBC-100)
…45 parts carbon black (manufactured by Columbia Carbon Co., Ltd.)
BAVEN1250)...4 parts Compound example (1)...2 parts The above formulation was uniformly premixed in a ball mill,
Prepare premixes. Next, the mixture was melt-kneaded with hot rolls, cooled, and then coarsely ground with a vibrating mill, and further finely ground using a Labojet (manufactured by Nippon Neumatic Co., Ltd.). The obtained fine powder is classified to have a particle size of 5 to 5.
A one-component black toner having a diameter of 35 μm was obtained. The blow-off charge amount of this toner is -21.6μC/gr
It was hot. In tests using a commercially available copying machine, images with high image density (1.45 or higher) and little fog were obtained. The toner transfer rate at that time was 92%. Comparative Example 1 A toner was prepared in the same manner as in Example 1 except that 1.2 parts of Comparative Compound Example (1) was used in place of Compound Example (1). A developer was prepared by mixing 97 parts of iron powder carrier with 3 parts of the obtained toner. The initial blow-off charge amount of this developer is rather low at -20.1μC/gr.
When a toner image was formed using a commercially available copying machine (Selenium drum), a good image with no fog was obtained in the initial copying, but after 5000 continuous copies, an unclear copied image was obtained. Comparative Example 2 A toner was prepared in the same manner as in Example 1 except that 1.2 parts of Comparative Compound Example (2) was used in place of Compound Example (1). A developer was prepared by mixing 97 parts of iron powder carrier with 3 parts of the obtained toner. The initial blow-off charge amount of this developer is quite low at -8.2μC/gr.
When a toner image was formed using a commercially available copying machine (Serendrum), an unclear copy image with a lot of fog was obtained even in the initial copying. [Effect of the invention] The above titanium metal complex compound used in the present invention is
As mentioned above, it has excellent charge amount (｜25｜μC/gr or more), high bulk (4.0cc/gr or more), and excellent pulverization property (5% or less), so it is easily dispersible in toner resin. It has the property of being extremely good. Therefore, the toner of the present invention containing a titanium metal complex compound as a charge control agent has a uniform amount of frictional charge between toner particles, and the amount of charge can be easily controlled. Furthermore, during use, the toner is extremely stable, with no change in quality or variation or decrease in the amount of triboelectricity. Therefore, problems such as development fog and contamination due to toner scattering are eliminated, clear toner images are obtained, and the toner images have excellent abrasion resistance, fixing properties, and adhesive properties.

Claims (1)

[Claims] 1. General formula [In the formula, R ₁ and R ₂ represent hydrogen, a nitro group, a halogen, a sulfonamide group, or an alkyl group (C ₁ to _{C 6} ), and R ₁ and R ₂ may be the same or different. good. A is a pyrazolone derivative residue which may have a substituent, [Formula] or [Formula] [wherein R ₃ is hydrogen, an alkyl group (C ₁ to C ₈ ), a carboxyl group, an alkyl group, or an aromatic group] Indicates an albamoyl group which may have a substituent. ]. ] A toner for electrostatic image phenomenon, characterized by containing a titanium metal complex compound represented by: 2. The toner for developing an electrostatic image according to claim 1, wherein the titanium metal complex compound represented by the general formula [] is contained in an amount of 0.3 to 5 parts by weight based on 100 parts by weight of the resin.