JP2612298B2 - Yellow color toner composition - Google Patents

Description

Description: TECHNICAL FIELD 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.

(Prior Art) 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 does not increase and the so-called fogging phenomenon does 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-mentioned problems of the color toner, and have excellent melt miscibility,
Furthermore, a dye having a stable image density obtained by continuous copying by repeated development and having good yellowness and light fastness was found, and the present invention was completed.

That is, the present invention relates to a method for preparing the binder resin according to the following general formula (I) (Wherein, R ₁ represents a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, R ₂ represents an alkyl group, an alkoxyalkyl group, an aralkyl group, or an alkoxycarbonylalkyl group, and R ₃ represents an alkyl group, an alkoxyalkyl Or an aralkyl group), which is a yellow color toner composition for electrostatic charge development.

Specific examples of R ₁ in the formula (I) include a halogen atom such as a hydrogen atom, a chlorine atom, a fluorine atom and a bromine atom, and an alkyl such as a methyl group, an ethyl group, a propyl group, an isobutyl group and an n-octyl group. Group, methoxy group, ethoxy group, n-
Examples include an alkoxy group such as a propoxy group and an n-hexyloxy group.

Specific examples of R ₂ include an alkyl group such as a methyl group, an ethyl group, a propyl group, an isobutyl group, an n-octyl group, a methoxymethyl group, a methoxyethyl group, an ethoxyethyl group, an n-propoxyethyl group, and an n-butoxy group. Alkoxyalkyl groups such as ethyl group, benzyl group, phenethyl group,
aralkyl groups such as γ-phenylpropyl group; and alkoxycarbonylalkyl groups such as methoxycarbonylmethyl group, ethoxycarbonylmethyl group and ethoxycarbonylethyl group.

Specific examples of R ₃ include an alkyl group such as a methyl group, an ethyl group, an isopropyl group, and an n-butyl group, a methoxymethyl group, a methoxyethyl group, an ethoxyethyl group, an n-propoxyethyl group, and an n-butoxyethyl group. Aralkyl groups such as an alkoxyalkyl group, a benzyl group, a phenethyl group and a γ-phenylpropyl group.

The compound of the general formula (I) can be easily obtained by diazotizing a substituted aniline compound and performing a coupling reaction with an N-substituted pyridone compound.

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

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

Particularly important components of the color toner are:
It is a pyridone-based compound represented by the aforementioned general formula (I).

The addition amount of these dyes for yellow color toner is
The chargeability of the binder resin, or a colorant added as an auxiliary,
Alternatively, the chargeability of the additive, and furthermore the compatibility with the binder resin,
Or because it is determined by the dispersion method, etc., it is not limited uniformly, but generally speaking, it is 0.
It is desirable to use it in the range of 1 to 10% by weight.

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 - Isoburen 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 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 has problems such as poor light fastness of a copy, occurrence of a fogging phenomenon, and poor melt miscibility. However, the toner composition of the present invention has excellent melt miscibility. However, it is a dye having a stable yellow color and good light fastness, which is obtained in continuous copying by repeated development, and is extremely valuable in practical use.

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

The light resistance of Examples 1 to 15 and Comparative Examples 1 and 2 was determined after irradiation with a fade meter (carbon arc lamp) at 63 ° C. for 60 hours.

Example 1 N-butyl-3-cyano-6-hydroxy- represented by
4-methyl-5- (4-methoxycarbonylphenyl)
5 parts of azopyridone and 95 parts of toner resin [styrene-acrylic acid ester copolymer; trade name Hymer TB-1000F (manufactured by Sanyo Chemical)] are mixed and pulverized by a ball mill, heated to 150 ° C., melt-mixed and cooled. The material is roughly pulverized using a hammer mill, and then finely pulverized by a fine pulverizer using an air jet method. 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. Using this developer, copying was performed with a dry plain paper electrophotographic copying machine (trade name, NP-5000; manufactured by Canon KK), and a clear yellow image without fog was obtained.
The light resistance of the copy was also good and was 6th grade.

Examples 2 to 15 Using the dyes shown in Table 1, a high-performance color toner composition was obtained in the same manner as in Example 1.

(Comparative Example 1) The dye for yellow color toner in the toner composition of Example 1 was a compound of the following formula (II) The procedure of Example 1 was repeated, except that 5.0 parts were used, to give a yellow lemon yellow, but the light fastness was poor and the grade was tertiary.

(Comparative Example 2) A dye for yellow color toner in the toner composition of Example 1 was a compound of the following formula (III) The procedure of Example 1 was repeated, except that 5.0 parts were used. As a result, a reddish yellow color was obtained, but the compatibility with the toner resin was inferior, the fog phenomenon occurred, and the light resistance was poor. It was grade 5.

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

Continuation of the front page Examiner Seiji Matsumoto (56) References JP-A-62-147465 (JP, A) JP-A-62-169166 (JP, A) JP-A-62-169167 (JP, A) JP 64-87665 (JP, A)

Claims (1)

(57) [Claims] 1. A compound of the formula (I) in a binder resin (Wherein, R ₁ represents a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, R ₂ represents an alkyl group, an alkoxyalkyl group, an aralkyl group, or an alkoxycarbonylalkyl group, and R ₃ represents an alkyl group, an alkoxyalkyl Or a aralkyl group.) A yellow color toner composition for electrostatic charge development, comprising a pyridone dye represented by the formula: