JPH0324559A - Electrophotographic magenta toner - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a color toner for electrophotography, and more particularly to a magenta toner for electrophotography containing a specific compound.

(Prior art) The electrophotographic method is described in US Patent No. 225'7A9/,
Publication No. 232/O and Special Publication Sho $3-2lL7ψ
According to various methods disclosed in Japanese Patent Publication No. After developing the powder image as necessary and transferring it to paper or the like, it is fixed by heating, pressure, solvent vapor, or the like.

1. In recent years, the electrostatic latent image of a document is exposed to spectral light, which is then developed with colored toners to obtain a colored copy image, or the copy images of each color are superimposed. A color copying method for obtaining a full-color copy image was put into practical use, and color toners such as neutral yellow, magenta, and cyan were produced by dispersing dyes and/or pigments of each color in a binder resin. ing.

The toner used is particles made by dispersing coloring agents such as dyes and pigments in a resin such as polyester and finely pulverizing the particles to a size of about 1 to 30 μm. is used in combination with a carrier material such as fur.

(Problems to be Solved by the Invention) However, it has been difficult for conventional color toners to satisfy various performances required of color toners.

In other words, with conventional color toners, (I) lack of light transmittance makes color reproduction difficult when overprinting multiple colors, and the primary overhead project (Of-I
When creating transparency for P), a good transparent image cannot be obtained.

{2} Good hue and color cannot be obtained because the spectral reflection characteristics are not good.

(3) Due to insufficient fastness to light and heat, the color of the Kobiichi image fades when left unused.

(4) Due to the low affinity between dyes and pigments and binder resin,
The dyes and pigments migrate to the photoreceptor, reducing its performance.

(5) Due to poor charging characteristics, the color balance deteriorates as more copies are made, causing defects such as capri density changes on the casing and images.

Such problems were occurring.

Therefore, as a result of intensive studies to solve these problems, the present inventors have found that by using a compound represented by a specific structural formula as a coloring agent, the above problems can be solved and various required properties can be satisfied in a well-balanced manner. The present invention was achieved by learning that an excellent toner can be obtained.

(Means for Solving the Problems) That is, the gist of the present invention resides in a magenta toner for electrophotography characterized by containing a compound represented by the following general formula (I) in a binder resin.

(In the formula, B represents a p-phenylene group which may have a substituent, Rl and R2 are each a hydrogen atom,
Substituted or unsubstituted alkyl group, cycloalkyl group,
R represents an allyl group or substituted or unsubstituted phenyl, or even if R forms a 6-membered hetero ring with the phenyl group B and the nitrogen atom, it is a hetero with R2 and the nitrogen atom! A membered ring or a 6-membered hetero ring may be formed. ) (Function) The present invention will be explained in detail below.

The colorant represented by the general formula (I) used in the present invention will be specifically explained. The substituents of the p-phenylene group represented by B include 01-C linear or branched alkyl groups, 4C-C linear or branched alkyl groups, fluorine atoms, Examples include halogen atoms such as chlorine atoms and bromine atoms, trifluoromethyl groups, etc. The substitution positions thereof are not particularly limited, and the number of substituents is possible in the range of 1-ψ, but particularly preferred substituents are Examples include a methyl group at the meta-position of an amino group. R and R
Examples of the alkyl group represented by IC%C8 include linear or branched alkyl groups, and examples of substituted alkyl groups include 2-hydroxyethyl JL J-
Hydroxy-substituted alkyl groups such as hydroxypropyl group, ≠-hydroxybutyl group, cohydroxypyl group; carboxymethyl group, 2-carboxyethyl group, 3
- Carboxy-substituted alkyl groups such as carpoxyglobyl group; Cyano-substituted alkyl groups such as 2-cyanoethyl group and cyanomethyl group; Amino-substituted alkyl groups such as λ-aminoethyl group; 2-chloroethyl group, 3-chloroprobyl group, Halogen atom-substituted alkyl groups such as Cochroprobyl group and 2,2.2-trifluoroethyl group; Phenyl-substituted alkyl groups such as penzyl group, p-chlorobenzyl group, and 2-phenylethyl group; 2-methyl-xyethyl group group, coethoxyethyl &. z-(nLy”roboxyethyl group, 2-(iso)proboxyethyl group,
λ-(nJ ptoxyethyl group, i-(iso)ptoxyethyl group sa-(λ-ethylhexyloxy)ethyl group, 3-methoxybuvir group, q-methoxybutyl group, 2
-Alkoxy-substituted alkyl group such as methoxyglobyl group: 2-C2-methoxyethoxy)ethyl group r2-(2-
ethoxyethoxy)ethyl group, 2-( 2 -(n)
Proboxyethoxy)ethyl group, 2-(2-
(iso)proboxyethoxy)ethyl group, λ-(-
2-(n)ptoxyethoxy)ethyl group, 'C2
(iso)butoxyethoxy)ethyl group%2-(2-
(2-ethylhexyloxy)ethoxy}Ethyl group Nato alkoxyalkoxy-substituted alkyl group; substituted alkyl groups such as co-allyloxyethyl group, 2-phenoxyethyl group, 2-penzyloxyethyl group; 2-acetyloxyethyl group, 2-propionyloxyethyl group%-2
-(n) butyryloxyethyl group, J - (iso)
Acyloxy-substituted alkyl groups such as butyryloxyethyl group and cotrifluoroacetyloxyethyl group;
Methoxyluponylmethyl group, ethoxyluponylmethyl group, (n) proboxylluponylmethyl group, (i
so) Propoxycarbonylmethyl group, (n) Proxycarbonylmethyl group, (iso)
-oxycarbonylmethyl group, coethylhexyloxycarbonylmethyl group, penzyloxycarbonylmethyl group, furfuryloxycarbonylmethyl group, tetrahydrofurfuryloxymethyl group, λ-methoxycarbonylethyl group, coethoxycarbonylethyl group t-
z-(n)7'roboxycarbonylethyl group s. z-
(tso) Proboxycarponylethyl group%-2-
(alt)butoxylponylethyl group, 2-(iso
) Substituted or unsubstituted alkoxycarbonyl-substituted alkyl groups such as butoxycarbonylethyl group, sx-(-z-ethylhexyloxycarbonyl)ethyl group, copenzyloxycarbonylethyl group, -2-furfurylcarbonylethyl group; Methoxycarbonyloxyethyl group, coethoxycarbonyloxyethyl group bz-
(n) Proboxyl group, 2-
(iso) Propoxycarbonyloxyethyl group, 2-(n) Proxycarbonyloxyethyl group, 2
- (iso) Substituted or unsubstituted carbonyloxyethyl group (12-C2-ethylhexyloxycarbonyloxy)ethyl group, 2-penzyloxycarponyloxyethyl group, 2-furfuryloxycarponyloxyethyl group, etc. Examples thereof include a substituted alkoxycarponyloxy alkyl group, a furfuryl group, and a heterocycle-substituted alkyl group such as a tetrahydrofurfuryl group.

The substituted phenyl groups represented by R1 and R2 include those having a C1 to C8 linear or branched alkyl group as a substituent, and those having a C1 to C8 linear or branched alkoxy group. Examples include those having a halogen atom such as a fluorine atom, a chlorine atom, and a bromine atom, and those having a nitro group, a cyano group, and a trifluoromethyl group.

Examples of the cycloalkyl group represented by R1 and R include a cycloalkyl group, a cyclopentyl group, and a cyclohexyl group.

Particularly advantageous among R1 and R2 are C1
~C linear or branched alkyl group, 8-cohydroxyethyl group, λ-cyanoethyl group, 2-chloroethyl group, benzyl group, cophenylethyl group, λ
1-(C1-C4 alkoxy)ethyl group, 2-allyloxyethyl group, 2-penzyloxyethyl group, -1#=2-(C,-C4 alkoxycarponyl)ethyl group, 2-acetyloxyethyl group, 2 One (C
-C4alkoxycarponyloxy)ethyl group, allyl group, etc.

A complex formed by combining R1, R2 and a nitrogen atom! Examples of the membered ring and the six-membered hetero ring include the following.

It will be done.

These dyes can be prepared using the following general formula (lI
[) Examples of the compound in which R1, the phenylene group B, and the nitrogen atom are combined to form a 6-membered heterocyclic ring include, for example, a compound represented by the following general II (II).

(In the formula, B and R2 represent the same meanings as above, and R
3, R4 and R5 each represent a hydrogen atom or a methyl group) More specific examples of the compounds represented by the general formula (I) include those shown in Table 1 (in the formula, B,R
1 and R2 have the same meanings as above) is subjected to an addition reaction with a cyanide compound such as sodium cyanide or potassium cyanide in an inert solvent such as N,N-dimethylformaldehyde or acetone, and then bromine It can be manufactured by oxidizing using an oxidizing agent such as.

The coloring agent to be contained in the magenta toner of the present invention is not limited to the specific compounds listed above, but it is also possible to use a mixture of two or more thereof.

In the magenta toner of the present invention, in addition to the compound represented by the above general formula (I), other colorants may be used in combination as long as the favorable effects of the compound are not impaired. Since the wavelength of reflected light of this compound is biased slightly toward the long wavelength side compared to conventional magenta toner, it is possible to add a blue colorant or a fluorescent whitening agent. Addition of a blue colorant and/or a fluorescent whitening agent is particularly effective when the magenta toner of the present invention is used for full-color copying together with conventional color toners of other colors such as cyan and yellow.

On the other hand, the binder resin for the magenta toner of the present invention can be selected from a wide range including known ones, but colorless and transparent ones are preferable, such as polystyrene,
Chloropo IJ Styrene-propylene copolymer, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene-maleic acid copolymer, styrene-acrylic acid ester copolymer (styrene-acrylic methyl acid copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer button, styrene-phenyl acrylate copolymer, etc.), styrene-methacrylate copolymer, etc. Polymer (styrene-methyl methacrylate copolymer,
Styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer and styrene-ferromethacrylate copolymer1), styrene-α-methyl chloroacrylate copolymer and styrene-acrylonitrile-acrylate copolymer Styrenic resins such as polymers (unipolymers or copolymers containing styrene-1-tapa-styrene substitutes), vinyl chloride resins,
Rosin-modified maleic acid resin, phenolic resin, epoxy resin, polyester resin, low molecular weight polyethylene, low molecular weight polypropylene, ionomer resin, polyurethane resin, silicone resin, ketone resin, ethylene-ethyl acrylate copolymer, xylene resin and polyvinyl petyral resin Particularly preferred resins for use in the present invention include styrene resins, saturated or unsaturated polyester resin buttons, and epoxy resins. However, the above resins are not limited to being used alone, but can also be used in combination of two or more.

The total amount of the above colorant added to the toner is 0.00 parts by weight of the binder resin. /~30 parts by weight is desirable, especially 0. Parts by weight of s to IO are desirable. If the amount added is too small, the coloring effect as a magenta color will be poor, and if it is too large, fixing properties will tend to be poor.

The charge control of the toner may be performed using the binder resin or dye/pigment itself, but if necessary, a charge control agent that does not cause problems in color reproduction may be used in combination. As the positive chargeability control agent, a basic/electron-donating substance such as a ψ-class ammonium salt is selected, and as the negative chargeability control agent, an acidic or electron-withdrawing substance such as metal chelates 1 or a metal-containing dye is selected as appropriate. It is good to use it.

The amount of the charge control agent to be added should be determined after considering conditions such as the chargeability of the binder resin, the manufacturing method including the amount and dispersion method of the colorant, and the chargeability of other additives. o per part by weight. i~/O parts by weight are suitable.

In addition, inorganic particles such as metal oxides or inorganic substances surface-treated with the above-mentioned organic substances may be used.

These charge control agents may be used by being mixed into the binder resin, or may be used in the form of being attached to the surface of the toner particles.

Furthermore, the electrical properties of the toner can be controlled by adding solid electrolytes, polymer electrolytes, charge transfer complexes, conductors such as metal oxides such as tin oxide, semiconductors, ferroelectric materials, magnetic materials, etc. can.

In addition, it is also possible to add various auxiliary agents such as plasticizers and release agents to the toner for the purpose of adjusting thermal properties, physical properties, etc. The amount added is suitably 0.00 to 0.00 parts by weight based on 0.00 parts by weight of the binder resin.

Furthermore, toner particles include TiO2, Al203, and SiO2.
The fluidity and agglomeration resistance of the toner can be improved by adding fine powders such as these and coating the surfaces of the toner particles. The amount added is binder resin/0
0 parts by weight. /~/O parts by weight are preferable.

Various conventional toner manufacturing methods can be applied to the toner manufacturing method of the present invention, and examples of general manufacturing methods include the following.

1. First, mix the resin and colorant (additives such as a charge control agent may be added depending on the case) using a ball mill, a V-type mixer,
Uniformly disperse using an S-type mixer, Henschel mixer, etc.

The dispersion is then melt-kneaded using a double-arm two-tar pressurized extrater roll mill or the like. The kneaded material is pulverized with a pulverizer such as a humer mill, cutter mill, jet mill, or pole mill, and the resulting powder is further classified with an air classifier or the like.

The resulting color toner can be mixed with a carrier and used as a developer for electrophotographic copying. As the button and carrier, it is preferable to use a magnetic material such as a known iron powder carrier or ferrite carrier, or a material coated on the surface thereof, in an amount of 0 to 100 parts per part of the toner. .

(Examples) The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to the following Examples unless the gist thereof is exceeded. Inside, each example button and the "part" in the comparative example
The term "parts by weight" refers to "parts by weight."

(Example/) 100 parts of unsaturated polyester resin The above compound/
(Boiled / in Table 1) j part Zinc salicylate complex compound / part The above materials were melt-kneaded in a hot roll mill, and after cooling, coarsely ground using a hammer mill, and then finely ground using an air jet type pulverizer. .

Classify the obtained fine powder and check the particle size! Particles of ~2 μm were selected to obtain magenta toner. Two parts of this magenta toner was added to 00 parts of iron powder and mixed in a V-type mixer to prepare a developer.

When this developer was used to make copies using a dry plain paper electrophotographic copying machine, there was no fog, the spectral reflection characteristics were good, and clear images were obtained. Although 20,000 copies were made in succession, there was no deterioration in the quality of the copied images. Among them, the image density after initial copying and after 20,000 copies is /. l! as well as/. J3, and the amount of charge of this toner is -l! at the initial stage of copying and after copying 20,000 sheets! ．． 3μc/f/and -/. ljμC/? The amount of charge was stable.

(Example 2) The same procedure as in Example 1 was carried out except that the resin was replaced with a styrene-n-butyl acrylate copolymer, and a clear image with good spectral reflection characteristics was obtained.

(Example 3) The same procedure as in Example 3 was carried out except that the colorant was replaced with Compound 7 (A7 in the table), and a clear image with good spectral reflection characteristics was obtained.

(Example 4t) The same procedure as in Example 1 was carried out except that the colorant was replaced with Compound 3/ (Black 3/ in Table/Inner), and a clear image with good spectral reflection characteristics was obtained.

(Example!) Use the above compound as a coloring agent! When the same procedure as in Example 1 was carried out except that IO (0 in the table/middle) was used, a clear image with good spectral reflection characteristics was obtained.

(Effects of the Invention) As explained above, the magenta toner for electrophotography of the present invention has
It satisfies the properties required for a color toner in a well-balanced manner, and among others, has excellent spectral reflection properties and good charging properties, so that stable images can always be obtained.

Claims (1)

[Scope of Claims] A magenta toner for electrophotography, characterized in that a binder resin contains a compound represented by the following general formula (I). ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, B represents a p-phenylene group that may have a substituent, and R^1 and R^2 are hydrogen atoms, substituted or unsubstituted, respectively. Represents a substituted alkyl group, cycloalkyl group, allyl group, or substituted or unsubstituted phenyl group, but R
^1 may form a 6-membered hetero ring with the phenyl group B and the nitrogen atom, or may form a 5-membered hetero ring or a 6-membered hetero ring with R^2 and the nitrogen atom. )