JP2010072286A - Electrophotographic toner and metal-containing compound - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide electrophotographic toner excellent in light resistance in an image part and improved in yellowing in the white part of printing paper around an image part, and to provide a metal-containing compound as the source material of the toner. <P>SOLUTION: The metal-containing compound is expressed by general formula (X-1), and the electrophotographic toner contains at least one compound. In the formula, Mx<SB>1</SB>represents a divalent metal ion; Rx<SB>1</SB>and Rx<SB>3</SB>each represents a hydrogen atom or a substituent; Rx<SB>2</SB>represents a hydrogen atom, an alkyl group or the like; wherein, at least one of Rx<SB>1</SB>and Rx<SB>3</SB>is a hetero five-membered cyclic group containing at least one atom selected from O, N and S atoms. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electrophotographic toner using a metal ion supply compound and a metal-containing compound.

  Color copier (registered trademark) using electrophotography and electrophotographic toners used in color printers include color reproducibility, image transparency, and light resistance. The electrophotographic toner in which the pigment used is dispersed in the particles as a colorant is excellent in light resistance because of the use of the pigment. However, since the colorant is insoluble, it easily aggregates, and the transparency decreases. The hue change of the transmitted color is a problem.

  Thus, toners in which the colorant is changed from a pigment to a dye have been disclosed (for example, see Patent Document 1). However, these toners have a problem in light resistance, although they are excellent in transparency and hue change. Since a very general dye has a relatively low molecular weight, it sublimates during heat fixing, and has the disadvantage of causing contamination on the surface of the fixing roller and the printer, reduction in image density, blurring, and the like.

  In order to solve these drawbacks, in recent years, a toner using a metal complex dye as a colorant has been disclosed (for example, see Patent Document 2). However, a toner containing the metal complex dye described above is light resistant. However, further improvement has been desired such as low reflection and different reflection spectra after printing due to aggregation and the like.

These problems were greatly improved by an electrophotographic toner using a metal-containing compound (see, for example, Patent Document 3), and an image obtained from this toner was excellent in color reproducibility and light resistance, but very good. Further, the performance required for the toner is not limited to this, and further improvement has been demanded for the yellowing of the white background around the image area.
JP-A-3-276161 Japanese Patent Laid-Open No. 10-20559 JP 2007-34264 A

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an electrophotographic toner excellent in light resistance of an image area and improved in yellowing of a white background portion of printing paper around the image area. It is to provide.

  As a result of diligent research, the present inventors have made it possible for a chelating reaction between the metal-containing compound and the dye to proceed rapidly if a specific metal-containing compound can be present in a stable dispersion state in the electrophotographic toner. The present invention was completed. That is, the above object of the present invention can be achieved by the following configuration.

  1. An electrophotographic toner comprising at least one metal-containing compound represented by the following general formula (X-1).

[Wherein, Mx ₁ represents a divalent metal ion, Rx ₁ and Rx ₃ represent a hydrogen atom or a substituent, and Rx ₂ represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, or a heterocyclic group. Represents an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfamoyl group, a sulfinyl group, an alkylsulfonyl group, an arylsulfonyl group or a cyano group. However, at least one of Rx ₁ and Rx ₃ is a heterocyclic 5-membered cyclic group containing at least one atom selected from an oxygen atom, a nitrogen atom, or a sulfur atom. ]
2. 2. The electrophotographic toner according to 1, wherein Mx ₁ in the general formula (X-1) is Cu ²⁺ .

  3. The metal containing compound represented by the following general formula (X-1).

[Wherein, Mx ₁ represents a divalent metal ion, Rx ₁ and Rx ₃ represent a hydrogen atom or a substituent, and Rx ₂ represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, or a heterocyclic group. Represents an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfamoyl group, a sulfinyl group, an alkylsulfonyl group, an arylsulfonyl group or a cyano group. However, at least one of Rx ₁ and Rx ₃ is a heterocyclic 5-membered cyclic group containing at least one atom selected from an oxygen atom, a nitrogen atom, or a sulfur atom. ]

  According to the present invention, it is possible to provide an electrophotographic toner that is excellent in light resistance of an image portion and that has improved yellowing of a white background portion of printing paper around the image portion.

  The present invention will be described in more detail.

  The structure represented by the general formula (X-1) will be described.

<< Compound Represented by Formula (X-1) >>
General formula (X-1) of this invention can also be represented using the limit structural formula of the following general formula (X-1a) and general formula (X-1b). In the present invention, the general formula (X-1), the general formula (X-1a), and the general formula (X-1b) are essentially the same and are not distinguished. The distinction between a covalent bond (indicated by −) and a coordination bond (indicated by...) Is also formal, and does not represent an absolute distinction.

The metal-containing compound in the present invention is preferably obtained by synthesizing a compound of the following general formula (X-2) and then reacting with a divalent metal compound. The method for synthesizing these metal-containing compounds can be synthesized in accordance with the method described in “Chelate Chemistry (5) Complex Chemistry Experimental Method [I] (Edited by Nanedo)”. Divalent metal compounds used include nickel chloride, nickel acetate, magnesium chloride, calcium chloride, barium chloride, zinc chloride, zinc acetate, titanium chloride (II), iron chloride (II), copper chloride (II), Cobalt chloride, manganese (II) chloride, lead chloride, lead acetate, mercury chloride, mercury acetate, etc. are mentioned, but as mentioned above, from the viewpoint of the color of the metal-containing compound itself and the color tone of the chelated dye, it is preferably chloride. Zinc, zinc acetate, nickel chloride, nickel acetate, copper chloride, copper acetate are preferred, and copper acetate is most preferred. The metal-containing compound used in the present invention may have a neutral ligand depending on the central metal, and typical ligands include H ₂ O or NH ₃ .

In the general formulas (X-1), (X-1a), and (X-1b), Mx ₁ represents a divalent metal ion, preferably a divalent transition metal ion. Among the divalent transition metal ions, nickel, copper, and zinc are preferable, and copper is most preferable from the color of the metal-containing compound itself and the color tone of the dye interacting with the general formula (X-1).

In General Formulas (X-1), (X-1a), General Formula (X-1b), and General Formula (X-2), Rx ₁ and Rx ₃ each represent a hydrogen atom or a substituent. The substituent represented by Rx ₁ and Rx _3, alkyl group (e.g., methyl group, an ethyl group, a propyl group, an isopropyl group, tert- butyl group, a pentyl group, a hexyl group, an octyl group, a dodecyl group, a tridecyl group , Tetradecyl group, pentadecyl group, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (eg, vinyl group, allyl group, etc.), alkynyl group (eg, ethynyl group, propargyl group, etc.), aryl group (eg, phenyl group, naphthyl group, etc.) Group), heteroaryl group (for example, furyl group, thienyl group, pyridyl group, pyridazyl group, pyrimidyl group, pyrazyl group, triazyl group, imidazolyl group, pyrazolyl group, thiazolyl group, benzoimidazolyl group, benzoxazolyl group, quinazolyl group) Group, phthalazyl group, etc.), heterocyclic group (for example, Loridyl group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), alkoxy group (for example, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, cyclopentyloxy group, cyclohexyl) Oxy group etc.), aryloxy group (eg phenoxy group, naphthyloxy group etc.), alkylthio group (eg methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, cyclopentylthio group, Cyclohexylthio group, etc.), arylthio group (for example, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (for example, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, Octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (eg, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, Butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), acyl group (for example, acetyl group) , Ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group Dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group, etc.), acyloxy group (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy) Group), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group) , Dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methyl) Aminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, phenylureido group, naphthylureido group, 2-pyridylaminoureido Group), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethyl Tylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (eg, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group) Group, dodecylsulfonyl group, etc.), arylsulfonyl group (phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (for example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino) Group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group), cyano group, nitro group, and the like.

  Preferred are a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an alkoxy group, an alkoxycarbonyl group, an acyl group, and a cyano group. These substituents may further substitute other substituents.

However, at least one of Rx ₁ and Rx ₃ is a heterocyclic 5-membered cyclic group containing at least one atom selected from an oxygen atom, a nitrogen atom or a sulfur atom, and is selected from an oxygen atom, a nitrogen atom or a sulfur atom. As long as at least one atom is included, the constituent atoms forming the ring are not particularly limited, but the constituent atoms are preferably a combination of atoms arbitrarily selected from carbon, nitrogen, oxygen, and sulfur atoms. As a furan ring, pyrrole ring, thiophene ring, pyrazole ring, imidazole ring, triazole ring, thiadiazole ring, oxazole ring, thiazole ring, benzothiazole ring, benzoxazole ring, benzoselenazole ring, benzotelrazole ring, benzimidazole Ring, thiazoline ring, indolenine ring, oxadiazole ring, pyrazolo Ring, isoxazolone ring, pyrrolidone ring, thioxathiazolone ring, pyrrolopyrrole ring, pyrroloimidazole ring, pyrrolotriazole ring, pyrazolopyrrole ring, pyrazoloimidazole ring, pyrazolotriazole ring, pyrazolopyrimidine ring, imidazolopyrazole Ring, isoxazolidine ring, thiooxaimidazolidine ring, imidazolidine ring, imidazolidinethione ring, thiazolidinone ring, etc., preferably furan ring, pyrrole ring, thiophene ring, pyrazole ring, imidazole ring, triazole ring, thiadiazole ring, Oxazole ring, thiazole ring, benzothiazole ring, benzoxazole ring, benzimidazole ring, thiazoline ring, indolenine ring, oxadiazole ring, pyrazolone ring, isoxazolone ring, pyrrolidone ring, pyrrolo A pyrrole ring, a pyrroloimidazole ring, a pyrrolotriazole ring, a pyrazolopyrrole ring, a pyrazoloimidazole ring, a pyrazolotriazole ring, a pyrazolopyrimidine ring, and an imidazolopyrazole ring. These may have a substituent at any position, and examples of the substituent include the same groups as the examples of the substituents of Rx ₁ and Rx ₃ described above.

Rx ₂ represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group, an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfamoyl group, a sulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, or a cyano group, As examples of each, in the examples of the substituents of Rx ₁ and Rx ₃ described above, the corresponding synonymous groups can be mentioned. Of these, a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an alkoxycarbonyl group, and a cyano group are preferable. These substituents may be further substituted with other substituents, and examples of the substituent include the same groups as those of the substituents of Rx ₁ and Rx ₃ described above.

  Specific examples of the metal-containing compound represented by the general formula (X-1) are shown below, but the present invention is not limited thereto. * In a table | surface has shown the coupling | bond part.

  Hereinafter, synthesis examples of the metal-containing compound represented by the general formula (X-1) of the present invention will be described.

  Synthesis Example 1 Synthesis of Exemplary Compound X-14

Synthesis of Compound B In a 500 ml three-necked flask, 90 g of Compound A, 21.5 g of cyanoacetic acid, 1.31 g of p-toluenesulfonic acid monohydrate and 300 ml of toluene were added and dehydrated using an ester tube. The mixture was heated and refluxed for 2 hours, the solvent was distilled off under reduced pressure, 500 ml of acetone was added and recrystallized to obtain 94.4 g of Compound B.

Synthesis of Compound C 5 g of Compound B, 25 ml of toluene, 3.3 g of triethylamine and 2.42 g of calcium chloride were added to a 100 ml three-necked flask and heated to 80 ° C. and stirred. After the internal temperature reached 80 ° C., thiophenecarboxylic acid chloride (Compound B-2) was added dropwise over 1 h. After completion of the dropwise addition, the mixture was cooled, separated with hydrochloric acid, neutralized with pure water, and the solvent was distilled off. 4.3 g of compound C was obtained by adding 50 ml of toluene and 50 ml of ethyl acetate and recrystallizing.

¹ H-NMR, CDCl ₃ δ = 0.88 (t, 3H), δ = 1.20-1.28 (m, 28H), δ = 1.42 (m, 2H), δ = 1.76 ( m, 2H), δ = 3.01 (t, 2H), δ = 3.93 (t, 2H), δ = 4.48 (t, 2H), δ = 6.87 (d, 2H), δ = 7.17-7.19 (m, 3H), δ = 7.92-7.97 (dd, 2H)
Synthesis of Exemplified Compound X-14 2 g of Compound C and 80 ml of acetone were added to a 200 ml three-necked flask and heated and stirred until the internal temperature reached 55 ° C. Thereafter, 0.35 g of copper acetate monohydrate was dissolved in 5 ml of a solvent of MeOH / water = 5/1 and added dropwise over 30 minutes. 1.9g of exemplary compound X-14 was obtained by filtering the depositing solid after completion | finish of dripping.

Synthesis Example 2 Synthesis of Exemplified Compound X-15 Same as Synthesis Example 1 except that Compound B-2 described in Synthesis Example 1 was changed to 2-furoyl chloride (CAS No. 527-69-5, Tokyo Chemical Industry Reagent). Example compound X-15 was thus obtained.

  Synthesis Example 3 Synthesis of Exemplary Compound X-26

  Exemplified compound X-26 was obtained in the same manner as in Synthetic Example 1, except that Compound B described in Synthetic Example 1 was changed to Compound D.

  For the metal-containing compound represented by the general formula (X-1) and the compound of the general formula (X-2) according to the present invention, refer to JP-A Nos. 2002-332259, 2003-237246, and 2007-31425. Can be synthesized.

  When a metal-containing compound is used by adding it to an electrophotographic toner, at least one chelateable dye is used for image formation. The chelatable dye need only be able to interact with the metal-containing compound of the present invention, such as chelate, and the detailed mechanism is unknown, but as a result of the interaction, the color of the dye itself and the output image In the present invention, it is more preferable to use those that improve the quality of the resin, improve the storage stability, and improve other physical properties. In selecting the dye, after various studies have been made so as to obtain the desired performance, a suitable one satisfying the desired performance may be selected. Examples of such a dye include the dyes described in JP-A-3-114892, JP-A-4-62094, JP-A-5-16545, JP-A-5-301470, and JP-A-5-177958.

  The yellow dye is preferably a dye represented by the following general formula (3).

In the formula, each of R ₁₁ and R ₁₂ represents a hydrogen atom or a substituent, R ₁₃ represents an alkyl group or an aryl group which may have a substituent, and Z is a 5- to 6-membered member together with 2 carbon atoms. Represents an atomic group necessary for constituting the aromatic ring.

  For the dye represented by the general formula (3), for example, a compound represented by the following general formula (A) can be obtained by referring to Chemical Reviews, Vol. 75,241 (1975) and can be produced according to a known coupling reaction with a compound represented by the following general formula (B).

_Wherein, R _11, R _{12, R 13} and Z have the same meanings as _{R 11,} R _{12, R 13} and Z of each of the general formula (3).

  Although the typical example of the yellow pigment | dye represented by General formula (3) below is shown, this invention is not limited to these.

  Preferably, the magenta dye includes a dye represented by the following general formula (4).

In the formula, R ₂₁ represents a hydrogen atom, a halogen atom or a substituent, and R ₂₂ represents an optionally substituted aromatic carbocyclic group or aromatic heterocyclic group. X represents a methine group or a nitrogen atom. R ₂₃ represents the following general formula (5) or (6), X ′ represents a carbon atom or a nitrogen atom, and Y represents an atomic group forming a nitrogen-containing aromatic heterocycle. W represents an atomic group forming an aromatic carbocycle or an aromatic heterocycle, and R ₂₄ represents an alkyl group.

  The dye represented by the general formula (4) can be synthesized according to a conventionally known method. For example, the azomethine dye in the general formula (4) can be synthesized according to the oxidative coupling method described in JP-A-63-113077, JP-A-3-275767, and 4-89287.

  Specific examples of the magenta dye represented by the general formula (4) are shown below, but the present invention is not limited thereto.

  The cyan dye is preferably a dye of the following general formula (6).

In the formula, R ₃₁ and R ₃₂ each represent a substituted or unsubstituted aliphatic group, and R ₃₃ represents a substituent. n represents an integer of 0 to 4, and when n is 2 or more, the plurality of R ₃₃ may be the same or different. R ₃₄ , R ₃₅ and R ₃₆ all represent an alkyl group, but R ₃₄ , R ₃₅ and R ₃₆ may be the same or different. _{However, R 35} and _{R 36} is an alkyl group having 3 to 8 carbon atoms.

  The dye represented by the general formula (6) can be synthesized according to a conventionally known method. For example, it can be synthesized according to the oxidative coupling method described in JP-A Nos. 2000-2255171, 2001-334755, 2002-234266 and the like.

  Specific examples of the cyan dye represented by the general formula (6) are shown below, but the present invention is not limited thereto.

  The electrophotographic toner of the present invention will be described below.

(Dye dispersion method)
The electrophotographic toner of the present invention is obtained by directly dispersing a dye dispersion in a binder resin or mixing a colored fine particle dispersion, and further using a desired additive described later, a kneading / pulverizing method, a suspension polymerization method, It can be produced by other known methods such as an emulsion polymerization method, an emulsion dispersion granulation method, and an encapsulation method. Among these production methods, the emulsion polymerization method is preferred from the viewpoints of production cost and production stability in consideration of the reduction in the toner particle size accompanying the increase in image quality. The emulsion polymerization method involves mixing the thermoplastic resin emulsion produced by emulsion polymerization with a dispersion of toner particle components, such as other dye solid dispersions, and agglomeration due to the repulsive force of the particle surface generated by pH adjustment and addition of an electrolyte. Toner particles are produced by slowly agglomerating while balancing the force, associating while controlling the particle size and particle size distribution, and simultaneously performing heating and stirring to control the fusion and shape between the fine particles.

  When directly dispersing the dye dispersion, it is possible to disperse using a commonly used roll grinder disperser, bead disperser, high-speed stir disperser, medium stirrer, etc. A similar method can be used. That is, it can also be obtained by dissolving (or dispersing) a dye in an organic solvent, emulsifying and dispersing in water, and then removing the organic solvent.

(Colored fine particles)
As one form of the electrophotographic toner of the present invention, at least colored fine particles can be dispersed in a thermoplastic resin. The colored fine particles further contain at least a metal complex compound represented by the general formula (1) or a dye represented by the general formula (2), and use a dispersion method such as an in-liquid drying method described later. By doing so, the dispersed particle diameter of the colored fine particles can be controlled. It is also preferable to further contain a resin having a composition different from that of the thermoplastic resin or a high-boiling solvent, and the dye is directly dispersed in a toner binder resin generally known as a toner using the above-mentioned dye, Alternatively, instead of dissolving, colored fine particles (including those in which a dye is simply dispersed) can be dispersed in a thermoplastic resin.

  Since the pigment in the colored fine particles dissolves in the resin at the molecular level, it becomes possible to eliminate components such as concealing particles that block light in the toner, and the transparency of each toner in a single color is improved. It is considered that transparency in the superimposed color is also improved. FIG. 1 schematically shows a cross section of an electrophotographic toner particle of the present invention in which colored fine particles are dispersed in a thermoplastic resin. As an example of a preferred form, the colored fine particles may be coated with an outer shell resin (shell) as shown in FIG. 2, and in this case, a resin and a thermoplastic resin (core) inside the colored fine particles (core) There are no restrictions on the combination of binder resins), the degree of freedom of materials is large, and the same manufacturing conditions are used if only the outer shell resin (shell) is the same for the four color toners (yellow, magenta, cyan, black). This makes it possible to manufacture with a large cost. In addition, since the dye that is the colorant does not migrate out of the colored fine particles (exposure to the surface of the colored fine particles), the dye sublimation or oil during heat fixing, which is generally regarded as a problem in toners using dyes. There is no concern about contamination.

(Preparation method of colored fine particles)
Next, an example of a method for producing colored fine particles, which is one of the preferred embodiments according to the present invention, will be described.

  The colored fine particles according to the present invention, for example, dissolve (or disperse) a dye (or dye and resin, a high-boiling organic solvent, an additive, etc.) in an organic solvent, and remove the organic solvent after being emulsified and dispersed in water. (In the case of a drying method in liquid), when a resin is further added and coated with an outer shell resin (shell), a monomer having a polymerizable unsaturated double bond is added to the colored fine particles, Colored fine particles having a core-shell structure can be obtained by conducting emulsion polymerization in the presence of an activator and depositing it on the core surface simultaneously with the polymerization. Alternatively, for example, an aqueous dispersion of resin fine particles is formed in advance by emulsion polymerization, an organic solvent solution in which a dye is dissolved is mixed in the aqueous dispersion of resin fine particles, and then the resin fine particles are impregnated with the dye, and then the coloring is performed. It can be obtained by various methods such as a method of forming a shell using fine particles as a core.

  The shell is preferably made of an organic resin, and as a method for forming the shell, there is a method in which a resin dissolved in an organic solvent is gradually dropped and the resin is adsorbed on the surface of the colored fine particle core simultaneously with the precipitation. After forming colored fine particles that form a core containing a dye and a resin, a monomer having a polymerizable unsaturated double bond is added, and emulsion polymerization is performed in the presence of an activator. A method of forming a shell is preferred.

  In addition, the dye may be formed by dispersing it in water using a surfactant or the like using a bead disperser, a high-speed agitation disperser, a medium type agitator, or the like.

(Normal surfactant)
In emulsification at the time of preparing colored fine particles, which is one of the preferred forms according to the present invention, a normal anionic emulsifier (surfactant) and / or a nonionic emulsifier (surfactant) may be used as necessary. it can.

  Examples of the normal nonionic emulsifier include, for example, polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether and polyoxyethylene stearyl ether, polyoxyethylene alkyl phenyl ethers such as polyoxyethylene nonylphenyl ether, and sorbitan monolaurate. Sorbitan higher fatty acid esters such as sorbitan monostearate and sorbitan trioleate, polyoxyethylene sorbitan higher fatty acid esters such as polyoxyethylene sorbitan monolaurate, polyoxyethylene monolaurate, polyoxyethylene monostearate, etc. Higher fatty acid esters of glycerin such as polyoxyethylene higher fatty acid esters, oleic acid monoglyceride, stearic acid monoglyceride Class, polyoxyethylene - polyoxypropylene - and the like block copolymer.

  Examples of the usual anionic emulsifier include higher fatty acid salts such as sodium oleate, alkylaryl sulfonates such as sodium dodecylbenzene sulfonate, alkyl sulfates such as sodium lauryl sulfate, polyethoxyethylene lauryl ether sulfate. Polyoxyethylene alkyl ether sulfates such as sodium, polyoxyethylene alkyl aryl ether sulfates such as sodium polyoxyethylene nonylphenyl ether sulfate, sodium monooctyl sulfosuccinate, sodium dioctyl sulfosuccinate, sodium polyoxyethylene lauryl sulfosuccinate And alkylsulfosuccinic acid ester salts, and derivatives thereof.

(dye)
The dye used in the present invention will be described.

  In the present invention, generally known dyes can be used. In the present invention, the dye is preferably an oil-soluble dye. Oil-soluble dyes are usually dyes that are soluble in organic solvents that do not have water-soluble groups such as carboxylic acids and sulfonic acids and are insoluble in water. However, oil-soluble dyes are oil-soluble by salting water-soluble dyes with long-chain bases. The dye which shows is also included. For example, acid dyes, direct dyes, and salt-forming dyes of reactive dyes and long chain amines are known.

  Although not limited to the following, for example, Valifast Yellow 4120, Variast Yellow 3150, Varifast Yellow 3108, Varifast Yellow 2310N, Varifast R1 304, Valifast R1 304, Valifast R3 , BaliFast Blue 2610, Valifast Blue 2606, VariFast Blue 1603, Oil Yellow GG-S, Oil Yellow 3G, Oil Yellow 129, Oil Yellow 107, Oil Yellow 105, Oil Yellow 105, Oil Yellow 105, Oil Yellow 105, Oil Yellow 105, Oil Yellow 105, Oil Yellow 105, Oil Yellow 105, Oil Yellow 105, Oil Yellow 105, Oil Yellow 105, Oil Yellow 105, Oil Yellow 105, Oil Yellow 105, Oil Yellow 105, Oil Yellow 105 Il Red RR, Oil Red OG, Oil Red 5B, Oil Pink 312, Oil Blue BOS, Oil Blue 613, Oil Blue 2N, Oil Black BY, Oil Black BS, Oil Black 860, Oil Black 5970Ol Black 5960 5905, Kayset Yellow SF-G, Kayset Yellow K-CL, Kayase Yellow GN, Kayase Yellow A-G, Kayset Yellow 2G, Kayset Red SF-4G, Kayase Red Kad SetK-4 -BR, Kayset Magenta 312, Kay set Blue K-FL, FS Yellow 1015, FS Magenta 1404, FS Cyan 1522, FS Blue 1504, C.I. I. Solvent Yellow 88, 83, 82, 79, 56, 29, 19, 16, 14, 04, 03, 02, 01, C.I. I. Solvent Red 84: 1, C.I. I. Solvent Red 84, 218, 132, 73, 72, 51, 43, 27, 24, 18, 01, C.I. I. Solvent Blue 70, 67, 44, 40, 35, 11, 02, 01, C.I. I. Solvent Black 43, 70, 34, 29, 27, 22, 7, 3, C.I. I. Solvent Violet 3, C.I. I. SolventGreen 3 and 7, Plast Yellow DY352, Plast Red 8375, MS Yellow HD-180 manufactured by Mitsui Chemicals, MS Red G, MS Magenta HM-1450H, MS Blue HM-1384, ES Red 3001, manufactured by Sumitomo Chemical Co., Ltd. , ES Red 3003, TS Red 305, ES Yellow 1001, ES Yellow 1002, TS Yellow 118, ES Orange 2001, ES Blue 6001, TS Turq Blue 618, Bayer's MACROL Yellow Yellow 6G, CeresBlu 75E , MACROLEX Red Vio let R and the like.

  Disperse dyes can be used as the oil-soluble dye, and are not limited to the following, but examples thereof include C.I. I. Disperse Yellow 5, 42, 54, 64, 79, 82, 83, 93, 99, 100, 119, 122, 124, 126, 160, 184: 1, 186, 198, 199, 204, 224 and 237; C . I. Disperse Orange 13, 29, 31: 1, 33, 49, 54, 55, 66, 73, 118, 119 and 163; C.I. I. Disperse Red 54, 60, 72, 73, 86, 88, 91, 92, 93, 111, 126, 127, 134, 135, 143, 145, 152, 153, 154, 159, 164, 167: 1, 177 , 181, 204, 206, 207, 221, 239, 240, 258, 277, 278, 283, 311, 323, 343, 348, 356 and 362; I. Disperse violet 33; C.I. I. Disperse Blue 56, 60, 73, 87, 113, 128, 143, 148, 154, 158, 165, 165: 1, 165: 2, 176, 183, 185, 197, 198, 201, 214, 224, 225 257, 266, 267, 287, 354, 358, 365 and 368 and C.I. I. Disperse Green 6: 1 and 9 etc. are mentioned.

  Other particularly preferable oil-soluble dyes include azomethine dyes and indoaniline dyes derived from couplers such as cyclic methylene compounds such as phenol, naphthols, pyrazolones and pyrazolotriazoles, and open-chain methylene compounds.

  Preferable examples of such dyes include, for example, JP-A-3-114892, JP-A-4-62092, JP-A-4-62094, JP-A-4-82896, JP-A-5-16545, JP-A-5-177958, and JP-A-5-301470. And dyes described in No. 1.

(Particle size)
The colored fine particles, which is one of the preferred forms in the present invention, preferably have a volume average particle diameter in the range of 10 nm to 1 μm. When the volume average particle diameter is 10 nm or less, the surface area per unit volume becomes very large. The effect of encapsulating the dye in the polymer of the colored fine particles is reduced, the stability of the colored fine particles is liable to deteriorate, and the storage stability is liable to deteriorate. On the other hand, when the particle size is larger than 1 μm, sedimentation is likely to occur during the production of the fine particle, and the stagnation stability is deteriorated. In addition, when the toner is used, the glossiness is deteriorated and the transparency is remarkably deteriorated. Therefore, the average particle diameter of the colored fine particles is preferably 10 to 1 μm, more preferably 10 to 500 nm, and still more preferably 10 to 100 nm.

  The volume average particle diameter can be determined using a dynamic light scattering method, a laser diffraction method, a centrifugal sedimentation method, an FFF method, an electrical detector method, etc. In the present invention, a Zetasizer manufactured by Malvern is used. Thus, it is preferable to obtain by the dynamic light scattering method.

(Dye content)
The colored fine particles according to the present invention preferably have a dye content in the range of 10 to 70% by mass. When the dye is contained in an amount of 10 to 70% by mass, a sufficient concentration can be obtained and the colorant can be protected by the resin. Since it is expressed and excellent in storage stability as a fine particle dispersion, it is possible to prevent an increase in particle size due to aggregation or the like.

(Metal-containing compound content)
The metal-containing compound represented by the general formula (X-1) may be used alone or in combination of two kinds, but is preferably 0.8 to 3 times the moles of the colorant, and more preferably Is 1 to 2 moles, depending on the dye used in combination, but if it is more than 0.8 moles, the light resistance is remarkably improved, and if it is less than 3 moles, the dispersion stability of the colored fine particles is improved. However, this is advantageous when toner is used.

(toner)
In the electrophotographic toner of the present invention, a known charge control agent, offset preventive agent and the like can be used in addition to the above-mentioned thermoplastic resin and colored fine particles. The charge control agent is not particularly limited. As the negative charge control agent used in the color toner, a colorless, white, or light color charge control agent that does not adversely affect the color tone and translucency of the color toner can be used. For example, a zinc or chromium metal complex of a salicylic acid derivative , Calixarene compounds, organoboron compounds, fluorine-containing quaternary ammonium salt compounds and the like are preferably used. Examples of the salicylic acid metal complex include those described in JP-A No. 53-127726 and JP-A No. 62-145255, and examples of the calixarene compound include, for example, JP-A No. 2-201378. As the organic boron compound, those described in JP-A-2-221967 can be used, and as the organic boron compound, for example, those described in JP-A-3-1162 can be used. is there. When such a charge control agent is used, it is desirable to use 0.1 to 10 parts by mass, preferably 0.5 to 5.0 parts by mass with respect to 100 parts by mass of the thermoplastic resin (binder resin).

  There are no particular restrictions on the anti-offset agent. For example, polyethylene wax, oxidized polyethylene wax, polypropylene wax, oxidized polypropylene wax, carnauba wax, sazol wax, rice wax, candelilla wax, jojoba oil wax, honey Wax wax or the like can be used. The added amount of such wax is 0.5 to 5 parts by mass, preferably 1 to 3 parts by mass with respect to 100 parts by mass of the thermoplastic resin (binder resin). This is because if the addition amount is less than 0.5 parts by mass, the effect of the addition is insufficient, and if it exceeds 5 parts by mass, the translucency and color reproducibility deteriorate.

  Moreover, in order to improve the preservability of a pigment | dye, the compound described and quoted on pages 10-13 of Unexamined-Japanese-Patent No. 8-29934 may be added as an image stabilizer, for example, the phenol type currently marketed, Examples include amine-based, sulfur-based, and phosphorus-based compounds. For the same purpose, for example, an organic ultraviolet absorbent or an inorganic ultraviolet absorbent may be added as an ultraviolet absorbent. Examples of organic ultraviolet absorbers include 2- (2′-hydroxy-5′-t-butylphenyl) benzotriazole and 2- (2′-hydroxy-3 ′, 5′-di-t-butylphenyl) benzotriazole. Benzotriazole compounds such as 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, etc., phenyl salsylate, 4-t-butylphenyl salsylate, 2, Hydroxybenzoates such as 5-t-butyl-4-hydroxybenzoic acid n-hexadecyl ester, 2,4-di-t-butylphenyl-3 ', 5'-di-t-butyl-4'-hydroxybenzoate System compounds and the like. Examples of inorganic ultraviolet absorbers include titanium oxide, zinc oxide, cerium oxide, iron oxide, and barium sulfate. Organic ultraviolet absorbers are preferred, and ultraviolet absorbers include 50% transmittance. The wavelength at 350 nm is preferably 350 to 420 nm, more preferably 360 nm to 400 nm. When the wavelength is lower than 350 nm, the ultraviolet blocking ability is weak, and when the wavelength is higher than 420 nm, the coloring becomes strong. Although there is no restriction | limiting in particular about addition amount, The range of 10-200 mass% is preferable with respect to a pigment | dye, and 50-150 mass% is more preferable.

(Thermoplastic Resin) Binder Resin As the thermoplastic resin contained in the electrophotographic toner of the present invention, a thermoplastic resin that has high adhesion to colored fine particles or copper complex compound fine particles, which is one of the preferred forms. Particularly preferred is a solvent-soluble one. Further, if the polymer precursor is soluble in a solvent, a curable resin that forms a three-dimensional structure can also be used. As the thermoplastic resin, those generally used as a binder resin for a toner are used without particular limitation. For example, styrene resins, acrylic resins such as alkyl acrylates and alkyl methacrylates, and styrene acrylic copolymer resins. Polyester resins, silicone resins, olefin resins, amide resins, or epoxy resins are preferably used. However, in order to improve transparency and color reproducibility of superimposed images, transparency and melting characteristics are high. Resins with low viscosity and high sharp melt properties are required. As the binder resin having such characteristics, styrene resins, acrylic resins, and polyester resins are suitable.

  The number average molecular weight (Mn) is 3000 to 6000, preferably 3500 to 5500 as the binder resin, and the ratio Mw / Mn of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 2 to 6, preferably 2. It is desirable to use a resin having a glass transition point of 0.5 to 5.5, a glass transition point of 50 to 70 ° C, preferably 55 to 70 ° C, and a softening temperature of 90 to 110 ° C, preferably 90 to 105 ° C.

  When the number average molecular weight of the binder resin is smaller than 3000, the image portion is peeled off when a full-color solid image is folded, and image defect occurs (folding fixability deteriorates). And the fixing strength decreases. If Mw / Mn is less than 2, high temperature offset is likely to occur. If Mw / Mn is greater than 6, sharp melt characteristics at the time of fixing deteriorate, and the translucency of toner and color mixing at the time of full color image formation decrease. End up. Further, if the glass transition point is lower than 50 ° C., the heat resistance of the toner becomes insufficient, and toner aggregation tends to occur during storage. Color mixing at the time of image formation is reduced. Further, when the softening temperature is lower than 90 ° C., high temperature offset tends to occur. When the softening temperature is higher than 110 ° C., fixing strength, translucency, color mixing property, and gloss of a full color image are deteriorated.

  The electrophotographic toner of the present invention uses the above-described thermoplastic resin (binder resin), colored fine particles, and other desired additives (the fine particles may be mixed in several kinds or in each kind of fine particles). Well), kneading and pulverizing methods, suspension polymerization methods, emulsion polymerization methods, emulsion dispersion granulation methods, encapsulation methods, and other known methods. Among these production methods, the emulsion polymerization method is preferred from the viewpoints of production cost and production stability in consideration of the reduction in the toner particle size accompanying the increase in image quality.

  In the emulsion polymerization method, the thermoplastic resin emulsion produced by emulsion polymerization is mixed with a dispersion of toner particle components such as other colored fine particles, and the balance between the repulsive force of the particle surface produced by pH adjustment and the cohesive force due to the addition of an electrolyte. The toner particles are produced by slowly agglomerating while taking particles, and performing association while controlling the particle diameter and particle size distribution, and at the same time, fusing and shape control between the fine particles by heating and stirring. The toner particles for electrophotography of the present invention preferably have a volume average particle diameter of 4 to 10 μm, preferably 6 to 9 μm, from the viewpoint of high-definition image reproducibility.

  In the electrophotographic toner of the present invention, a post-treatment agent can be added and mixed from the viewpoint of imparting toner fluidity and improving cleaning properties, and is not particularly limited. Examples of such post-treatment agents include inorganic oxide fine particles such as silica fine particles, alumina fine particles, and titania fine particles, inorganic stearate compound fine particles such as aluminum stearate fine particles and zinc stearate fine particles, and strontium titanate and titanium. Inorganic titanate compound fine particles such as zinc oxide can be used, and it is possible to use single or different additives in combination. These fine particles are desirably used after being surface-treated with a silane coupling agent, a titanium coupling agent, a higher fatty acid, silicone oil, etc. from the viewpoints of environmental stability and heat-resistant storage stability. On the other hand, it is desirable to use 0.05 to 5 parts by mass, preferably 0.1 to 3 parts by mass.

  The toner for electrophotography of the present invention can be used as a two-component developing toner used by mixing with a carrier, or as a one-component developing toner not using a carrier.

  As the carrier used in combination with the electrophotographic toner of the present invention, conventionally known carriers can be used as a carrier for two-component development, for example, a carrier made of magnetic particles such as iron or ferrite, A resin-coated carrier obtained by coating such magnetic particles with a resin, or a binder-type carrier obtained by dispersing magnetic fine powder in a binder resin can be used. Among these carriers, a silicone resin, a copolymer resin (graft resin) of an organopolysiloxane and a vinyl monomer, or a resin-coated carrier using a polyester resin can be used as a coating resin, such as toner spent. From the viewpoint, a carrier coated with a resin obtained by reacting an isocyanate with a copolymer resin of an organopolysiloxane and a vinyl monomer is particularly preferable from the viewpoint of durability, environmental stability, and spent resistance. . As the vinyl monomer, it is necessary to use a monomer having a substituent such as a hydroxyl group reactive with isocyanate. In addition, it is preferable to use a carrier having a volume average particle diameter of 20 to 100 μm, preferably 20 to 60 μm from the viewpoint of ensuring high image quality and preventing carrier fogging.

(Image forming method)
Next, an image forming method using the electrophotographic toner of the present invention will be described.

  In the present invention, the image forming method is not particularly limited. For example, a method of forming a plurality of images on a photosensitive member and transferring them in a batch, a method of sequentially transferring images formed on the photosensitive member to a transfer belt, etc. are not particularly limited, but more preferably a plurality of images on the photosensitive member. This image is formed and transferred at once.

  In this method, the photosensitive member is uniformly charged and exposed in accordance with the first image, and then the first development is performed to form a first toner image on the photosensitive member. Next, the photoconductor on which the first image is formed is uniformly charged, and exposure according to the second image is given, and the second development is performed to form a second toner image on the photoconductor. Further, the photoconductor on which the first and second images are formed is uniformly charged, exposure according to the third image is performed, the third development is performed, and a third toner image is formed on the photoconductor. . Further, the photosensitive member on which the first, second, and third images are formed is uniformly charged, exposed according to the fourth image, developed for the fourth time, and the fourth toner image on the photosensitive member. To form.

  For example, a full color toner image is formed on the photosensitive member by developing the first time with yellow, the second time with magenta, the third time with cyan, and the fourth time with black toner. Thereafter, the image formed on the photoreceptor is collectively transferred to an image support such as paper, and further fixed on the image support to form an image.

  In this method, the images formed on the photoconductor are collectively transferred to paper or the like to form an image. Therefore, unlike the so-called intermediate transfer method, the number of times of transfer that disturbs the image is one time. In fact, the image quality can be improved.

  Non-contact development is preferable because a plurality of developments are necessary as a method of developing on the photoreceptor. In addition, a method in which an alternating electric field is applied during development is also a preferable method.

  As described above, the non-contact development method is preferable as the development method for forming a superimposed color image on the image forming body and transferring the images collectively.

  The volume average particle size of the carrier that can be used as the two-component developer is 15 to 100 μm, more preferably 25 to 60 μm. The volume average particle diameter of the carrier can be typically measured by a laser diffraction particle size distribution measuring apparatus “HELOS” (manufactured by SYMPATEC) equipped with a wet disperser.

  The carrier is preferably further coated with a resin, or a so-called resin-dispersed carrier in which magnetic particles are dispersed in the resin. The resin composition for coating is not particularly limited, and for example, olefin resin, styrene resin, styrene / acrylic resin, silicone resin, ester resin, or fluorine-containing polymer resin is used. The resin for constituting the resin-dispersed carrier is not particularly limited, and known resins can be used. For example, styrene / acrylic resin, polyester resin, fluorine resin, phenol resin, etc. are used. Can do.

  A preferred fixing method used in the present invention is a so-called contact heating method. In particular, typical examples of the contact heating method include a heat roll fixing method and a pressure heating fixing method in which fixing is performed by a rotating pressure member including a fixedly arranged heating body.

(image)
In image formation in which development, transfer, and fixing are performed using the electrophotographic toner of the present invention, the state from the transfer to the fixing is that the electrophotographic toner of the present invention transferred onto the transfer material is fixed after fixing. However, the colored fine particles are not disintegrated and are attached to the surface of the paper in a dispersed state in the toner particles.

  In the present invention, since the colored fine particles are dispersed in the toner particles as described above, the toner particles contain a high concentration of the dye, but the dye is not released to the surface of the toner particles (does not migrate). This is a problem of the toner in which the dye obtained by dispersing or dissolving the dye in the thermoplastic resin (toner binder resin) as it is conventionally is exposed on the surface of the toner particles. 2) Large difference in charge amount between high temperature and high humidity and low temperature and low humidity (environment-dependent) 3) Kind of colorant For example, each pigment of cyan, magenta, yellow and black is used for full color image recording. When the toner is used, it is possible to wipe away the variation in charge amount of each color toner. In addition, there is no migration of the dye, which is a colorant, outside the colored fine particles (exposure to the surface of the colored fine particles) during heat fixing to the transfer material. There will be no dye sublimation or oil contamination.

  EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these embodiments. In the examples, “part” or “%” is based on mass unless otherwise specified.

Example 1
A pulverized toner and a polymerized toner were prepared by using the following pulverized toner manufacturing method and polymerized toner manufacturing method (two types).

<Preparation method of pulverized color toner>
105 parts of a polyester resin, a mixture of the colorant shown in Table 1 and the metal-containing compound of the present invention (1.00 / 1.05 molar ratio), the following addition parts, polypropylene resin (Biscol 550P: manufactured by Sanyo Chemical Co., Ltd.) 5 Were mixed, ground meat, pulverized, and classified to obtain a powder having an average particle size of 8.5 μm. Further, 100 parts of this powder and 1.0 part of silica fine particles R805 (manufactured by Nippon Aerosil Co., Ltd., particle diameter 12 nm, hydrophobization degree 60) were mixed with a Henschel mixer to obtain a pulverized color toner.

Yellow 5.0 parts Magenta 2.5 parts Cyan 2.5 parts <Preparation of polymerization color toner>
<Preparation of Colorant Dispersion 1>
20 g of a mixture of the colorant shown in Table 1 and the metal-containing compound of the present invention (1.00 / 1.05 molar ratio) was added to a solution in which 5 g of sodium dodecyl sulfate was dissolved in 200 ml of pure water. A water dispersion of magenta colorant and low molecular weight polypropylene (number average molecular weight 3,700) were emulsified in water to give a solids concentration of 30% with a surfactant while applying heat. An emulsified dispersion was prepared.

<Preparation of Color Toner 1>
The colorant dispersion 1 is mixed with 57 g of a low molecular weight polypropylene emulsified dispersion, and 225 g of styrene, 43 g of butyl acrylate, 13 g of methacrylic acid, 5.4 g of t-dodecyl mercaptan as a chain transfer agent, After adding 000 ml, emulsion polymerization was carried out by maintaining at 70 ° C. for 3 hours while stirring under a nitrogen stream.

  Sodium hydroxide was added to 1,000 ml of the resulting dispersion of colorant-containing resin fine particles to adjust the pH to 7.0, 270 ml of a 2.7 mol / l potassium chloride aqueous solution was added, and 160 ml of i-propyl alcohol and 9.0 g of polyoxyethylene octyl phenyl ether having an average degree of polymerization of ethylene oxide of 10 was dissolved in 67 ml of pure water and added, and the reaction was carried out by stirring for 6 hours while maintaining at 75 ° C. The obtained reaction liquid was filtered and washed with water, and further dried and crushed to obtain colored particles.

  These colored particles and 1.0 part of silica fine particles R805 (supra) were mixed with a Henschel mixer to obtain a polymerization method color toner 1.

<Manufacture of carriers>
When an external magnetic field of 40 g of styrene / methyl methacrylate (4/6) copolymer fine particles (average particle size 80 nm), Cu—Zn ferrite particles (specific gravity 5.0, mass average particle size 45 μm, 1,000 oersted) is applied. Is charged into a high-speed agitating mixer, mixed at 30 ° C. for 15 minutes, then set to 105 ° C., mechanical impact force is repeatedly applied for 30 minutes, and the carrier is cooled and cooled. Got.

<Production of developer for live-action test>
The carrier 214g and each toner 16g were mixed for 20 minutes using a V-type mixer to produce developers 1 to 28 for a live-action test. The obtained developer composition is shown in Table 1.

<Image formation>
Using a color copying machine (KL-2010: manufactured by Konica Minolta Co., Ltd.) as an image forming apparatus, actual image evaluation was performed.

  As the fixing device, a commonly used heat roll fixing type was used. Specifically, the surface of a cored bar (inner diameter = 40 mm, wall thickness = 1.0 mm, total width = 310 mm) made of an aluminum alloy with a heater built in the center is coated with tetrafluoroethylene-perfluoroalkyl vinyl ether. A heated roller is formed by coating with a 120 μm thick tube of coalescence (PFA), and the surface of a cylindrical core made of iron (inner diameter = 40 mm, wall thickness = 2.0 mm) is made of sponge silicone rubber (Asker C A pressure roller was formed by coating with a hardness of 48 and a thickness of 2 mm, and the heating roller and the pressure roller were brought into contact with a load of 150 N to form a 5.8 mm wide nip.

  Using this fixing device, the printing linear velocity was set to 440 mm / sec. As a cleaning mechanism for the fixing device, a web type supply system impregnated with polydiphenyl silicone (having a viscosity at 20 ° C. of 10 Pa · s) was used. The fixing temperature was controlled by the surface temperature of the heating roller (set temperature 176 ° C.). The amount of silicone oil applied was 0.1 mg / A4.

<Image evaluation>
With the developer using the color toner of the present invention, a reflection image (image on paper) sample was prepared on plain paper using the above-described image forming apparatus, and evaluated by the following method. The toner adhesion amount was evaluated in the range of 0.75 ± 0.05 (mg / cm ² ).

《Light resistance》
After measuring the image density D ₀ immediately after recording, a 6-day exposure test was performed using “Xenon Long Life Weather Meter” (Xenon Arc Lamp, 70,000 lx, 24.0 ° C.) manufactured by Suga Test Instruments Co., Ltd. The image density D was measured again, and the dye residual ratio was calculated and evaluated from the difference in image density before and after the xenon light irradiation.

A: Dye remaining ratio 80% or more B: Dye remaining ratio 70% or more and less than 80% C: Dye remaining ratio 60% or more and less than 70% D: Dye remaining ratio 60% or less is there.

<Evaluation of yellowing of white background around the image area>
The sample of the reflected image (image on paper) was stored for 3 days under conditions of 55 ° C. and 90% RH, and then yellowing around the image portion was visually evaluated.

A: No yellowing is observed at all. B: Slight yellowing is observed, but there is no practical problem. C: Clear yellowing is observed around the image area. A and B are levels where there is no practical problem. .

  The obtained results are summarized in Table 1.

  As can be seen from Table 1, by using the color toner of the present invention, since the light resistance is good, it is possible to provide an image showing a good storage property for a long period of time, and also the yellowing around the image portion is improved. I was able to do it.

Claims (3)

An electrophotographic toner comprising at least one metal-containing compound represented by the following general formula (X-1).

[Wherein, Mx ₁ represents a divalent metal ion, Rx ₁ and Rx ₃ represent a hydrogen atom or a substituent, and Rx ₂ represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, or a heterocyclic group. Represents an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfamoyl group, a sulfinyl group, an alkylsulfonyl group, an arylsulfonyl group or a cyano group. However, at least one of Rx ₁ and Rx ₃ is a heterocyclic 5-membered cyclic group containing at least one atom selected from an oxygen atom, a nitrogen atom, or a sulfur atom. ] Formula (X-1) Mx ₁ in the toner for electrophotography according to claim 1, characterized in that the ^{Cu 2+.} The metal containing compound represented by the following general formula (X-1).

[Wherein, Mx ₁ represents a divalent metal ion, Rx ₁ and Rx ₃ represent a hydrogen atom or a substituent, and Rx ₂ represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, or a heterocyclic group. Represents an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfamoyl group, a sulfinyl group, an alkylsulfonyl group, an arylsulfonyl group or a cyano group. However, at least one of Rx ₁ and Rx ₃ is a heterocyclic 5-membered cyclic group containing at least one atom selected from an oxygen atom, a nitrogen atom, or a sulfur atom. ]