JP2644299B2 - Magenta color toner composition - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color toner, and more particularly to a composition for a negatively chargeable color toner for electrostatic charge development.

As a method for forming a visible image by developing an electric latent image with a color toner, a conventional electrostatic printing method, an electrophotographic method, and the like are well known. In general, by various means using a photoconductive substance, an electric latent image is formed on a photoconductor showing photoconductivity, and then the latent image is developed with toner to obtain a visible image, or After the powder image is transferred to paper or the like, if necessary, it is fixed by heating, pressurizing, or solvent vapor to obtain a visible image.

In order to obtain a color multicolor image, a document is exposed using a color separation filter, and the above process is repeated a plurality of times using color toners such as yellow, magenta, and cyan to form a color image.

Conventionally, as a toner for developing an electric latent image, particles obtained by pulverizing a dispersion of a colorant in a binder resin such as polystyrene into about 0.1 to 50 μm have been used.
This color toner is usually mixed with a carrier substance such as glass beads or iron powder and used for developing an electric latent image.

(Problems to be Solved by the Prior Art and the Invention) These color toners are required to have various physical and chemical properties described below.

(1) The triboelectric properties of the color toner are not affected by the temperature change.

(2) the density obtained by the collision of the color toner particles and the carrier particles due to the repeated development for continuous use, and the mutual deterioration of the particles and the photosensitive plate, or
The background density must not increase and degrade the quality of the copy.

(3) When an attempt is made to increase the density of a copied image by increasing the amount of color toner adhering to the surface of a photosensitive plate having a latent image, the background density generally increases, so that the so-called fogging phenomenon must not occur.

(4) Transparency must not be lost in order to perform multicolor superposition.

(5) Each color toner needs to be excellent in melt miscibility.

(6) Spectral reflection characteristics must be good for accurately reproducing an original.

Many of the known color toners cannot be said to sufficiently satisfy the above-mentioned required characteristics, and at present, improvement is demanded.

(Means for Solving the Problems) The present inventors have conducted intensive studies to solve the above-described problems of the color toner, and have excellent melt miscibility,
Further, the present inventors have found a dye which is stable in image density obtained by continuous copying by repeated development and has good magenta color and fastness to light, and has completed the present invention.

That is, the present invention relates to the following resin represented by the following general formula (I): (Wherein, R represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an alkoxyalkyl group, an alkoxyalkoxy group, an aralkyl group, an alkoxycarbonyl group, or an alkylcarboxy group). Magenta color toner composition for electrostatic charge development.

Specific examples of R in the formula (I) include a hydrogen atom, a chlorine atom, a fluorine atom, a halogen atom such as a bromine atom, a methyl group, an ethyl group, a propyl group, an isobutyl group, a t-butyl group, an n- Alkyl group such as octyl group, methoxy group,
Alkoxy groups such as ethoxy group, n-propoxy group, n-hexyloxy group, methoxymethyl group, methoxyethyl group, ethoxyethyl group, n-propoxyethyl group, n-
Alkoxyalkyl group such as butoxyethyl group, methoxymethoxy group, ethoxymethoxy group, alkoxyalkoxy group such as ethoxyethoxy group, benzyl group, phenethyl group, aralkyl group such as r-phenylpropyl group, methoxycarbonyl group, ethoxycarbonyl group, Examples thereof include an alkoxycarbonyl group such as an n-propoxycarbonyl group, an acetyloxy group, an ethylcarboxy group, and an alkylcarboxy group such as an n-propylcarboxy group.

The compound of the general formula (I) is 1-amino-2-chloro-
It can be easily obtained by reacting 4-hydroxyanthraquinone and dihydroxybenzenes in a polar solvent in the presence of a base such as potassium carbonate.

As a method for producing a color toner using the magenta dye of the present invention, a color toner is obtained by preferably containing 0.1 to 10 parts by weight of a compound of the formula (I) in a binder resin. Can be.

Hereinafter, the components of the color toner of the present invention will be described in detail.

Particularly important components of the color toner are:
An anthraquinone compound represented by the above general formula (I).

The amount of these dyes for magenta color toner is
Uniformly limited because it is determined by the charge static of the binder resin or the chargeability of the colorant or additive that is added as an additive, and the compatibility with the binder resin or the dispersion method, etc. However, generally speaking, it is desirable to use it in the range of about 0.1 to 10% by weight based on the binder resin.

As the binder resin applied to the color toner of the present invention,
Although all known ones are possible, for example, polystyrene, poly p-chlorostyrene, a homopolymer of styrene such as polyvinyltoluene and a substituted product thereof, a styrene-vinylnaphthalene copolymer, a styrene-methyl acrylate copolymer, Styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate Copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, Styrene-butadiene copolymer, styrene Down - isoprene copolymer, styrene - acrylonitrile - indene copolymer, styrene -
Maleic acid copolymer, styrene-based copolymers such as styrene-maleic acid ester copolymer, polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride,
Polyvinyl acetate, polyethylene, polypropylene, polyester, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorine Paraffin, paraffin wax and the like can be used alone or in combination.

Examples of the carrier as a developer include magnetic substances such as iron, cobalt, and nickel, alloys and mixtures thereof, and coatings on the surfaces thereof.

(Operation) The conventional toner composition has problems such as poor light fastness of a copy, occurrence of a fog phenomenon, and poor melt miscibility. However, the toner composition of the present invention has excellent melt miscibility. The image density obtained by continuous copying by repeated development has a stable magenta color and a good light fastness dye,
It is extremely valuable in practice.

(Examples) Hereinafter, the present invention will be described in more detail with reference to examples. The compound used was manufactured by a conventional method.

In addition, the light resistance of Examples 1 to 17 was determined after irradiation for 60 hours at 63 ° C. with a fedometer (carbon arc lamp).

Example 1 5 parts of 1-amino-4-hydroxy-2- (p-hydroxyphenyl) anthraquinone represented by the following formula, and 95 parts of a resin for toner [styrene-acrylate copolymer; trade name Hymer TB-1000F (manufactured by Sanyo Chemical)] Is mixed and pulverized by a ball mill, heated to 150 ° C., melt-mixed, cooled, coarsely pulverized by using a hammer mill, and then finely pulverized by an air jet type pulverizer. After further classification, 1 to 20 μm is selected to obtain a toner.

For 10 parts of this toner, use carrier iron powder (trade name, EFV2
90/50; Nippon Iron Powder Co., Ltd. 90 parts were uniformly mixed to obtain a developer. Copying was performed using a dry plain paper electrophotographic copier (trade name, NP-5000; manufactured by Canon KK) using this developer.
A clear magenta image without fog was obtained. or,
The light resistance of the copy was good, and it was grade 6.

Examples 2 to 17 In the same manner as in Example 1 except that the dyes shown in Table 1 were used, high-performance color toner compositions were obtained.

(Effect of the Invention) In the developer using each dye in the example, the one obtained by copying can obtain a clear magenta image without fog,
In addition, the light fastness is good, but the image obtained by copying with the developer using each dye in the comparative example has poor light fastness, further poor compatibility between the toner and the resin, and may cause fogging. I understand.

Incidentally, the dye of the formula (I) is used as a polymerizable dye by reacting with, for example, vinyl isocyanate, and if it is copolymerized with styrene, methyl acrylate, etc., the dye resin which is covalently bonded to the resin can be purified. And an excellent color toner composition can be obtained.

Claims (1)

(57) [Claims] 1. A compound of the formula (I) in a binder resin (Wherein, R represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an alkoxyalkyl group, an alkoxyalkoxy group, an aralkyl group, an alkoxycarbonyl group, or an alkylcarboxy group). A magenta color toner composition for electrostatic charge development.