JPH0341472A - Yellow toner for electrophotography - Google Patents

Abstract

PURPOSE:To obtain the yellow toner having various good characteristics, such as optical characteristics and electrostatic charge characteristics, such as optical characteristics and electrostatic charge characteristics by incorporating a specific compd. into a binder resin. CONSTITUTION:The yellow toner for electrophotography having the various good characteristics including enhanced light transmittability, spectral reflecting characteristic, affinity of a dye, pigment and a binder resin, electrostatic charge characteristic, and fastness to light and heat is obtd. when the compd. expressed by general formula I is incorporated into the binder resin. In the formula, X: a hydrogen atom or halogen atom; R: alkyl group, alkoxyalkyl group which may be substd.; aralkyloxyalkyl group which may be substd., aryloxyalkyl group which may be substd., tetrahydrofurfuryl group, fufuryl group, cycloalkyl group, allyl group or aralkyl group.

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 yellow toner for electrophotography containing a specific compound.

(Prior art) The electrophotographic method is described in U.S. Patent No. 229769/1986.
Publication No. 2-23910 and Special Publication Sho 1I3-, t4tq
As disclosed in various publications such as the QG publication, generally an electrostatic latent image of electrostatic charge is formed on a photoreceptor containing a photoconductive material by various means, and then the latent image is developed as a powder image with toner. After the powder image is transferred to paper or the like as required, it is fixed by heating, pressure, solvent vapor, or the like.

In addition, in recent years, the electrostatic latent image of the document is formed by exposing it to spectral light, and this is developed with color toner of each color to obtain a colored copy image, or the copy images of each color are superimposed to form a full-color image. A method of color copying to obtain copied images has been put into practical use, and color toners such as yellow, magenta, and cyan, which are made by dispersing dyes and/or pigments of various colors in a binder resin, have been manufactured. ing.

The toner used is particles made by dispersing coloring agents such as dyes and pigments in a resin such as polyester and finely pulverized to about 30 μm. It is used by mixing with a carrier material such as.

(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, conventional color toners (1) lack light transparency, which makes color reproduction difficult when overprinting multiple colors, and overhead project (○HP)
A good transparent image cannot be obtained when creating a transparent range.

(2) Since the spectral reflection characteristics are too good, good hues and colors cannot be obtained.

(3) Due to insufficient fastness to light and heat, the color of the copied image fades during storage.

(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 the number of copies increases, and defects such as fogging and density changes occur on images.

Such problems were occurring.

Therefore, the present inventors have found that it is possible to solve these problems by using a compound represented by a specific structural formula, and to create an excellent toner that satisfies various required properties in a well-balanced manner. The present invention was achieved by learning that the following can be obtained.

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

(In the formula, X represents a hydrogen atom or a halogen atom, and R is an alkyl group, an optionally substituted alkoxyalkyl group, an optionally substituted aralkyloxyalkyl group, an optionally substituted allyloxyalkyl group) , an optionally substituted aryloxyalkyl group, a tetrahydrofurfuryl group, a furfuryl group, a cycloalkyl group,
Represents an allyl group or an aralkyl group. ) (Function) The present invention will be described in detail below.

The quinophthalone dye represented by the general formula (I) used in the present invention will be explained.

- Examples of the alkyl group for R in the above formula (I) include methyl group, ethyl group, propyl group, butyl group, pentyl group,
Examples include linear or branched C1-C, □ alkyl groups such as hexyl, heptyl, octyl, decyl, and dodecyl groups.

Examples of the optionally substituted alkoxyalkyl group include niemethoxyethyl group, 4-ethoxyethyl &, 2-(
n) propoxyethyl group 1.2-(iso)propoxyethyl group, 2-Cn) butoxyethyl group, J-(is
o) Butoxyethyl group, 4-(sec) butoxyethyl group 1.2-(n) pentyloxyethyl group,! −(n
,)hexyloxyethyl group, 2-(n)octyloxyethyl group, co(2-ethylhexyloxy)ethyl group, /-methyl-2-methoxyethyl group, /-methyl-
4-ethoxyethyl group, /-methyl-2-Cn) propoxyethyl group, /-methyl-2-(iso)propoxyethyl group, /-methyl-2-(n,) butoxyethyl group, l-methyl-s -(iso)buto 6 xyethyl group, /-methyl-=2-(n)hexyloxyethyl group, /-methyl-2-(,2-ethylhexyloxy)ethyl group, 3-methoxyphthyl group, 3-ethoxy Butyl group, /-ethyl-niemethoxyethyl group, /-
Examples include ethyl-4ethoxyethyl group, but especially C
A 3-C8 β-alkoxyethyl group is preferred.

Examples of the optionally substituted aralkyloxyalkyl group include nibenzyloxyethyl group, /-methyl-nibenzyloxyethyl group, /ethyl-nibenzyloxyethyl group, and 1.2-(β-phenylethyl)oxyethyl group. Can be mentioned.

Examples of the allyloxyalkyl group which may be substituted include co-allyloxyethyl group, /-methyl-neeallyloxyethyl group, /-ethylneelyloxyethyl group, and the like.

Examples of the optionally substituted aryloxyalkyl group include a niphenoxyethyl group, a /-methyl-cophenoxyethyl group, and a /-ethyl-niphenoxyethyl group.

Examples of the cycloalkyl group include a cyclopentyl group and a cyclohexyl group.

Examples of the aralkyl group include benzyl group and 4-phenylethyl group. Examples of the halogen atom for X include a chlorine atom and a bromine atom.

However, these dyes may be used in combination if necessary.

As a method for producing the dye used in the yellow toner of the present invention, for example, JP-A-Sho SO-/1 (aQ39VC
It can be carried out by the known methods described.

Specific examples of these dyes are shown in Table/.

Table/ The coloring agent to be contained in the yellow toner of the present invention is not limited to the specific examples listed above, but a mixture of two or more compounds represented by the above-mentioned film type (I) may be used. It is also possible. Further, compounds other than these metal compounds may be used in combination as a coloring agent, as long as the desired effects produced by using the compound are not impaired. Furthermore, the compound can be mixed with toners of other colors and used for color improvement.

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, but colorless and transparent ones are preferable, such as polystyrene,
Chloropolystyrene, poly-α-methylstyrene, styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene copolymer, styrene-
Vinyl chloride copolymer, styrene-vinyl acetate copolymer,
Styrene-maleic acid copolymer, styrene-acrylic acid ester copolymer (styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer) styrene-phenyl acrylate copolymer), styrene-methacrylate ester copolymer (styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, and styrene - phenyl methacrylate copolymer, etc.), styrene-based resins such as styrene-α-methyl chloroacrylate copolymer, and styrene-acrylonitrile-acrylic acid ester copolymer (monopolymers or copolymers containing styrene or styrene substitutes) polymer), vinyl chloride resin, rosin-modified maleic acid resin, phenol resin,
Epoxy resins, polyester resins, low molecular weight polyethylene, low molecular weight polypropylene, ionomer resins, polyurethane resins, silicone resins, ketone resins, ethylene-ethyl acrylate copolymers, xylene resins, polyvinyl butyral resins, etc. are used in the present invention. Particularly preferred resins include styrene resins, saturated or unsaturated polyester resins, and epoxy resins. Moreover, the above resins are not limited to being used alone, but four or more types can also be used in combination.

The total amount of the colorant added to the toner is preferably 0.7 to 30 parts by weight, particularly 0.7 to 30 parts by weight, based on 100 parts by weight of the binder resin. s to 70 parts by weight is desirable. If the amount added is too small, the coloring effect as a yellow color will be poor, and if it is too large, the fixing property will be poor and preferably it will tend to be dull.

The charge control of the toner may be performed using the binder resin or the dye/pigment itself, but if necessary, various charge control agents may be used in combination so as not to cause problems in color reproduction. As the positive chargeability control agent, a basic/electron-donating substance such as a grade ammonium salt, and as the negative chargeability control agent, an acidic or electron-withdrawing substance such as metal chelates or metal-containing dyes may be appropriately selected and used. good.

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. 0.0% by weight. /~10 parts by weight is appropriate.

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

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

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 0.7 to 70 parts by weight per 100 parts by weight of the inder resin.

Furthermore, the toner particles contain T i 02, Al2O3, S
By adding fine powder such as i02 and coating the surfaces of toner particles, it is possible to improve the fluidity and agglomeration resistance of the toner. The amount added is preferably 0.7 to 70 parts by weight per 100 parts by weight of the binder resin.

Various conventional toner manufacturing methods can be applied to the toner manufacturing method of the present invention.

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

Next, the dispersion is melt-kneaded using a double-arm Niegoo, pressure kneader-extruder roll mill, or the like. The mixed material is pulverized using a pulverizer such as a hammer mill, cutter mill, shelving mill, or ball mill, and the resulting powder is further classified using 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 carrier, it is preferable to use a magnetic material such as a known iron powder carrier or a ferrite carrier, or a carrier coated on the surface thereof in an amount of 70 parts to 700 parts per part of 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. In addition, in each example and comparative example, "part"
The term "parts by weight" refers to "parts by weight."

(Example/) Unsaturated polyester resin 100 parts Above table/of/f
Compound 6.2 3 parts Zinc salicylate complex compound / part The above materials were melt-kneaded in a hot roll mill, cooled, and then coarsely ground using a hammer mill, and then finely ground using an air jet type pulverizer.

Two parts of toner was added to 100 parts of iron powder, and mixed in a V-type mixer to prepare a developer.

When this developer was used for copying with a dry plain paper electrophotographic copying machine, there was no fog, the spectral reflection characteristics were good, and clear images were obtained. Also, when I made 200 copies in succession using this developer, the quality of the copied images deteriorated considerably.

In addition, the image density at the initial stage of copying and after copying 50,000 sheets is /, l15 and Otsu /13, and the amount of charge of this toner is -/6 at the initial stage of copying and after copying 20,000 sheets.
, 3 μC/9 and -/tile 4 μC/9, and the amount of charge was stable.

(Example 2) The same procedure as in Example 2 was obtained except that a styrene-n-butyl acrylate copolymer was used instead of the unsaturated polyester resin, and the same results as in Example 2 were obtained.

(Example 3) The same procedure as Example 3 was obtained except that the compound 7 in the table 1 was used instead of the compound 1462 in the table 1, and the same results as in Example 3 were obtained. Ta.

(Example 11) The same procedure as Example/ was performed except that the compound of AI in the table/ above was used instead of the compound /I62 in the table/ above, and the same results as in Example/ were obtained. It was done.

(Example S) 7 The same procedure as Example/ was performed except that the compound /46/7 in the table/ above was used instead of the compound l162 in the table/ above, and the results were the same as in Example/. was gotten.

(Effects of the Invention) As explained above, the yellow toner for electrophotography of the present invention satisfies the properties required for a color toner in a well-balanced manner, among others, has excellent spectral reflection properties, good charging properties, and is always stable. An image is obtained.

Claims (1)

[Claims] (1) A yellow toner for electrophotography, which contains a compound represented by the following general formula (I) in a binder resin. ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・・・・
[I] (wherein, X represents a hydrogen atom or a halogen atom, R is an alkyl group, an optionally substituted alkoxyalkyl group, an optionally substituted aralkyloxyalkyl group, an optionally substituted allyl group) oxyalkyl group, optionally substituted aryloxyalkyl group, tetrahydrofurfuryl group, furfuryl group, cycloalkyl group,
Represents an allyl group or an aralkyl group. )