JPH11174736A - Two-component yellow toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the two-component yellow toner having good spectral reflecting property, superior environmental resistance and durability by incorporating a specified compd. and a colorless electrostatic charge controlling agent into a bonding resin and specifying the mixing weight ratio between the carrier and the toner. SOLUTION: The two-component yellow toner for forming an image by multicolor superposition contains a compd. represented by the formula and a colorless electrostatic charge controlling agent in a bonding resin. The mixing weight ratio between a carrier and the toner is regulated to 100:(1-10). In the formula, X<1> and X<2> are each halogen or 1-5C alkyl and X<3> and X<4> are each H of halogen but both X<3> and X<4> are not H. The pref. amt. of the compd. is 0.1-20 pts.wt., particularly 1-10 pts.wt. based on 100 pts.wt. of the resin. A combination of two or more such compds. may be used so as to modify the color tone.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-component yellow toner particularly suitable for color electrophotography.

[0002]

2. Description of the Related Art Electrophotography is disclosed in U.S. Pat. No. 2,297,691.
No., JP-B-42-23910 and JP-B-43-43.
As variously disclosed in, for example, Japanese Patent No. 24748, an electrostatic latent image of an electrostatic charge is generally formed on a photoconductor containing a photoconductive material by various means, and then the latent image is developed as a powder image with toner. If necessary, the powder image is transferred to paper or the like, and then fixed by heating, pressurizing, or solvent vapor.

Further, in recent years, an electrostatic latent image of a document is formed by exposing with a split light, and is developed with a color toner of each color to obtain a colored copy image, or a copy image of each color is superimposed. In addition, a color copying method for obtaining a full-color copy image has been put to practical use, and a color toner such as yellow, magenta, cyan, or the like, in which a dye and / or a pigment of each color is dispersed in a binder resin, is used as a color toner for this purpose. Have been. As the toner, one obtained by dispersing a coloring agent such as a dye or a pigment in a resin such as polyester is used.
Particles finely pulverized to about 30 μm are used, and such a toner is used by being mixed with a carrier substance such as glass beads, iron powder, or fur.

[0004]

A color toner is required to have the following characteristics, similarly to a commonly used black toner.・ Excellent triboelectric charging characteristics. -The characteristics do not change significantly depending on the environment such as temperature and humidity, that is, the environment dependency is small. -Less deterioration, that is, durability against repeated continuous use. Further, the following characteristics are also indispensable as unique to the color toner. -Spectral reflection characteristics must be good to faithfully reproduce the original. -Robust against light and heat and should not fade even if left unattended.・ High transparency for multi-color superposition. -Good color mixing with other color toners. However, in practice, the properties of the toner vary greatly depending on the type and amount of the components such as the colorant, and it is quite difficult to satisfy all of the above-mentioned required characteristics. It is.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and it is an object of the present invention to satisfy the above-mentioned required characteristics in a well-balanced manner, and particularly to have good spectral reflection characteristics, environmental resistance and durability. Another object of the present invention is to provide a two-component yellow toner having excellent characteristics in terms of toner properties. Accordingly, the present inventors have conducted intensive studies to achieve such an object, and as a result, by including a specific compound and a colorless charge control agent in the binder resin, and by defining the mixing weight ratio of the carrier and the toner. The present inventors have found that a two-component yellow toner satisfying the above objects can be obtained, and have reached the present invention. That is, the gist of the present invention is a two-component yellow toner for obtaining an image by multicolor superposition, comprising a compound represented by the following general formula (I) and a colorless charge control agent in a binder resin. A two-component yellow toner, wherein the mixing weight ratio of the carrier and the toner is set to 100: 1 to 10.

[0006]

Embedded image

[0007] wherein, X ¹ and X ² each represent a halogen atom or an alkyl group having 1 to 5 carbon atoms, X ³ and X
⁴ represents a hydrogen atom or a halogen atom, respectively, except when both are hydrogen atoms. ]

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The two-component yellow toner of the present invention is characterized in that the binder resin contains the compound represented by the general formula (I). Specific examples of the compound represented by the general formula (I) include, for example,

[0009]

Embedded image

And the like. The amount of these additives is preferably in the range of 0.1 to 20 parts by weight, and particularly preferably in the range of 1 to 10 parts by weight, based on 100 parts by weight of the resin. As a means for adjusting the color tone to obtain a desired yellow color, two or more compounds represented by the above general formula (I) may be used in combination, and other colorants such as a monoazo type and a disazo type may be used. A colorant selected from pigments such as isoindolinone type and dyes such as anthraquinone type, quinoline type and diphenylmethane type, and one or two or more types other than the compound represented by the general formula (I). It may be added to form a mixed color.

On the other hand, the binder resin for the yellow toner of the present invention can be selected from a wide range including known ones. Specifically, styrene-based resins such as polystyrene, styrene-acrylate copolymer, styrene-methacrylate copolymer and styrene-butadiene copolymer, saturated polyester resin, unsaturated polyester resin, epoxy resin , Phenolic resin,
Examples include a coumarone resin, a chlorinated paraffin, a xylene resin, a vinyl chloride-based resin, polyethylene, and polypropylene. These resins may be appropriately used in combination of two or more.

Among these, styrene resins,
The use of saturated or unsaturated polyester resins and / or epoxy resins is advantageous. Further, the following colorless charge control agent is added to the toner of the present invention. For example, in order to obtain a negatively chargeable toner, a metal complex of salicylic acid or alkyl salicylic acid is preferable, and in the case of a positively chargeable toner, a quaternary ammonium salt or a salt forming compound thereof is preferable. 0.1-5w in toner
When the content is in the range of t%, sufficient chargeability can be imparted to the toner without deteriorating the characteristics of the toner, and thus it is preferable.

In the yellow toner of the present invention, a fluidity improver such as colloidal silica is added to the toner in an amount of 0.1%.
About 01 to 3 wt% may be added. In addition, a cleaning aid such as a metal stearate may be added.

The toner of the present invention is used as a two-component developer by mixing it with a carrier. As the carrier, conventionally known ones such as iron powder and ferrite powder having a particle size of about 50 to 200 μm can be used. Further, those obtained by coating these surfaces with a silicone resin, an acrylic resin, a fluorine-based resin, or the like, or a mixture of these resins can also be suitably used. The mixing weight ratio of the carrier and the toner is 100:
1 to 10.

Although the yellow toner of the present invention can be produced by various production methods including conventionally known methods, examples of general production methods include the following. A resin, a colorant, and a colorless charge control agent (other additives such as a fluidity improver and a cleaning aid may be optionally added) may be uniformly dispersed with a Henschel mixer or the like. The dispersion is melt-kneaded with a kneader, extruder, roll mill or the like. The kneaded material is roughly pulverized by a hammer mill, a cutter mill, or the like, and then finely pulverized by a jet mill, an I-type mill, or the like. The finely pulverized material is classified by a DS (dispersion classifier), a zigzag classifier or the like. In some cases, silica or the like is dispersed in the classified material using a Henschel mixer or the like. Further, as a completely different method from the above-mentioned production method, for example, production by a suspension polymerization method can be mentioned.

[0016]

[Example 1]

 Styrene / n-butyl acrylate copolymer (monomer ratio: 8/2, weight average molecular weight: 40,000) 100 parts Chromophtal Yellow 3G 5 parts Colorless charge control agent (3,5-di-tert-butylsalicylic acid chromium complex) 1 part

The above-mentioned ingredients were melt-kneaded in a hot roll mill, cooled, coarsely crushed using a hammer mill, and then finely crushed with an air jet-type fine crusher. The resulting fine powder was classified to select a particle size of 5 to 20 μm to obtain a toner. The hydrophobic silica R97 is applied to the toner particles.
2 (manufactured by Nippon Aerosil Co., Ltd., trade name) was externally added by 0.5% by weight with a Henschel mixer to obtain a yellow toner. To 3 parts of the toner, 97 parts of a carrier (ferrite powder coated with a silicone resin and having an average particle diameter of about 100 μm) were mixed with a V blender to obtain a negatively chargeable developer.

Using this developer, a commercially available dry copying machine using selenium as a photoreceptor at normal temperature and normal humidity (25 ° C., 60% R
Under H), a continuous live-action test was performed. As a result, 200
It was found that even after 00 sheets, the spectral reflection characteristics without fog were very good, a clear yellow copy was obtained, and the durability was excellent. Further, the developer was brought into a high-temperature and high-humidity environment (35 ° C., 85% RH), and the same continuous actual shooting test was performed.
Even after 0 sheets, a very clear yellow-colored copy without fog was obtained, and the environmental characteristics were also found to be good.

Example 2 Polyester resin synthesized from bisphenol A and terephthalic acid (weight average molecular weight: 80,000) 100 parts Chromophtal Yellow 6G 5 parts Colorless charge control agent (Chromium complex of 3,5-di-tert-butylsalicylic acid) 1 copy

A developer was produced in exactly the same manner as in Example 1 except that the materials used were as described above, and a continuous actual test was performed. As a result, in both the normal temperature and normal humidity and the high temperature and high humidity environments, a clear yellow copy with extremely good spectral reflection characteristics and without a decrease in image density or an increase in fog after actual printing of 20,000 sheets was obtained.

Example 3 Styrene / n-butyl acrylate copolymer (monomer ratio: 7/3, weight average molecular weight: 60000) 100 parts Chromophtal Yellow GR 5 parts Colorless charge control agent (benzyltributylammonium chloride and naphtholsulfonic acid) 3 parts)

The materials having the above formulation were melt-kneaded by a hot roll mill, cooled, coarsely ground by a hammer mill, and then finely ground by an air jet-type fine mill. The obtained fine powder was classified, and a particle size of 5 to 20 μm was selected to obtain a yellow toner. 97 parts of a carrier (ferrite powder coated with an acrylic resin and having an average particle diameter of about 100 μm) was mixed with 3 parts of the toner by a V blender to obtain a positively chargeable developer.

Using this developer, a dry copying machine using a commercially available organic photoconductor as a photoreceptor at normal temperature and normal humidity (25 ° C., 60 ° C.)
% RH). As a result, 2
Even after 0000 sheets, it was found that fog-free, extremely excellent spectral reflection characteristics and a clear yellow color copy were obtained, and that the image was excellent in durability. Further, this developer was brought into a high-temperature and high-humidity environment (35 ° C., 85% RH), and a similar continuous actual shooting test was performed.
Even after 0 sheets, a very clear yellow-colored copy without fog was obtained, and the environmental characteristics were also found to be good.

[0024]

The two-component yellow toner of the present invention satisfies the characteristics required for a color toner, such as good spectral reflection characteristics and excellent environmental resistance and durability, in a sufficient and well-balanced manner.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hirofumi Oda 1-Fukudacho, Joetsu-shi, Niigata Pref. Naoetsu Works, Mitsubishi Chemical Corporation

Claims (1)

[Claims] 1. A two-component yellow toner for obtaining an image by multicolor superposition, comprising a compound represented by the following general formula (I) and a colorless charge control agent in a binder resin: The mixing weight ratio of the carrier and the toner is 100: 1.
A two-component yellow toner, wherein Embedded image [In the formula, X ¹ and X ² each represent a halogen atom or an alkyl group having 1 to 5 carbon atoms, and X ³ and X ⁴ each represent a hydrogen atom or a halogen atom, except when both are hydrogen atoms. . ]