JPWO2008023657A1 - Toner for electrophotography, image forming method and squarylium dye - Google Patents

Abstract

The present invention allows for good coloring without causing dispersibility in a thermoplastic resin as a problem, is excellent in transparency and color reproducibility, and has excellent heat resistance, chargeability, and offset resistance, An image forming method using the toner for electrophotography and a novel squarylium dye are provided. This electrophotographic toner contains a dye represented by the following general formula (1). [Chemical 1]

Description

  The present invention relates to an electrophotographic toner, an image forming method using the electrophotographic toner, and a novel squarylium dye.

  As various electrophotographic methods are disclosed (for example, see Patent Documents 1 and 2), an electrostatic latent image of an electrostatic charge is generally formed on a photoreceptor containing a photoconductive substance by various means, and then The latent image is developed as a powder image with toner, and the powder image is transferred to paper or the like, if necessary, and then fixed by heating, pressurization, or solvent vapor.

  In recent years, an electrostatic latent image of an original is formed by exposure with spectral light, and this is developed with each color toner to obtain a colored copy image, or each color copy image is superimposed to obtain a full color copy image. As a color toner used for this, color toners of yellow, magenta, cyan and the like in which pigments and / or dyes of various colors are dispersed in a binder resin are produced.

  The above-mentioned electrophotographic method generally forms an image by the following steps.

  First, an electrostatic latent image is formed on the photosensitive member by irradiating the photosensitive member made of a photoconductive material with optical information corresponding to image information by various methods. Next, the electrostatic latent image formed on the photosensitive member is developed as a toner image with charged toner, and the toner image is transferred to an image recording medium (such as plain paper or an intermediate transfer member) for thermal fixing. An image is fixed on plain paper using an apparatus.

  In the color image forming method using the above-described electrophotographic method, the electrostatic latent image formed on the photoconductor corresponds to image information separated into yellow, magenta, cyan, and black colors, respectively. The toner of the same color as the image information is developed. A color image is formed by repeating this development process four times for each color.

  Conventionally known organic pigments and dyes have been used as colorants used in electrophotographic toners, but each has various drawbacks. For example, organic pigments are generally superior in heat resistance and light resistance compared to dyes, but because they exist in the form of particles dispersed in the toner, the hiding power is increased and transparency is reduced. End up. Further, since the dispersibility of the pigment is generally poor, the transparency is impaired, the saturation is lowered, and the color reproducibility of the image is hindered.

  Also, among the color-superposed toners, the lowermost toner is not concealed by the uppermost toner, so that the color of the lowermost toner can be visually confirmed. In addition, the transparency of the toner is required, and in order to maintain the color reproducibility of the original, the dispersibility of the colorant and the coloring power are required.

  As a method for eliminating the above-mentioned drawbacks of the pigment, for example, by using a flushing method as a pigment dispersion method, by achieving a submicron order pigment dispersion diameter by primary particles without aggregated secondary particles, transparency is achieved. Means for improving and means for improving chargeability, fixability, and image uniformity by coating pigment particles with a binder resin and an outer shell resin have been proposed (for example, see Patent Document 3). However, even in the case of outputting with the toner proposed in these cases, it is still difficult to obtain sufficient transparency in the case of the toner using pigment.

  In color image forming apparatuses, in principle, all color reproduction can be performed by subtractive color mixing with the three primary colors of yellow, magenta, and cyan. However, in reality, the spectral characteristics when pigments are dispersed in a thermoplastic resin. The range of color reproducibility and saturation are reduced by the color mixing property when toners of different colors are overlapped with each other. Therefore, many problems still remain in faithfully reproducing the color of an original.

  On the other hand, a toner using a dye (see, for example, Patent Document 4) and a toner in which a dye and a pigment are mixed are disclosed. Generally, in a toner using a dye, the dye is contained in a binder resin of the toner. Since it exists in a dissolved state, it has excellent transparency and saturation, but has the disadvantage that its light resistance and heat resistance are greatly inferior to pigments. Regarding heat resistance, in addition to a decrease in density due to the decomposition of the dye, when the toner image is fixed by a heat roller, the dye is sublimated and easily causes internal contamination, and the dye dissolves in the silicone oil used at the time of fixing, Eventually, there was a problem of causing an offset phenomenon by fusing to a heating roll. As a proposal for solving these disadvantages of dyes, for example, means for making light resistance, sublimation and color reproducibility compatible by using a specific anthraquinone dye or chelate dye as magenta toner (for example, Patent Document 5) See). Further, as a highly saturated toner, for example, a toner using a squarylium dye (see, for example, Patent Document 6) has been proposed.

  On the other hand, copper phthalocyanine pigments are well known as cyan toners, and those that are soluble in organic solvents have also been put into practical use. The storage stability (for example, light resistance) is very high, but the color tone is affected by aggregation and the like. It is not yet satisfactory, and the color reproducibility of green, which is an intermediate color, is particularly low.

  In Patent Document 6, it is described that the pulverization type dye for cyan toner has high saturation, but there is no description of dispersibility, and the dispersion stability due to the low solubility of these squarylium dyes. Is becoming a problem. Even in the case of outputting with the toners proposed in these cases, it is still difficult to obtain sufficient heat resistance (sublimation), light resistance and color reproducibility in the case of toners using dyes, and these conditions are satisfied. Development of a toner that can be used is desired.

On the other hand, squarylium dyes have been synthesized since the 1960s, and are known as, for example, plasma display filters (see, for example, Patent Document 7) and photopolymerization initiation sensitizing dyes (see, for example, Patent Document 8). However, there is no description about the use of the toner, and for the above purpose, since the addition amount is extremely small, the solubility is not a problem. However, as a dye for an image display material, a high solubility in an organic solvent or a resin is required, and development of a dye having a high solubility and a good color tone is desired.
US Pat. No. 2,297,691 Japanese Patent Publication No.42-23910 JP-A-11-160914 JP-A-5-11504 Japanese Patent No. 3567403 JP 2000-345059 A JP 2001-350013 A JP-A-6-287210

  The object of the present invention was made to solve the above-mentioned problems, and enables good coloring without causing dispersibility in thermoplastic resin as a problem, and is excellent in transparency and color reproducibility. It is to provide an electrophotographic toner excellent in heat resistance, chargeability and offset resistance, an image forming method using the electrophotographic toner, and a novel squarylium dye.

  The above object of the present invention is achieved by the following configurations.

  1. An electrophotographic toner comprising a dye represented by the following general formula (1):

(In the formula, Q ₁ and Q ₂ each represents an atomic group necessary for forming a 5-membered or 6-membered nitrogen-containing heterocycle, and may be condensed or have a substituent. _{1 to} L ₁₀ each independently represents an unsubstituted or substituted methine group, R ₁ and R ₂ each represent a substituent, and m1, m2, n1, and n2 each represents 0 or 1)
2. 2. The electrophotographic toner according to 1 above, wherein the coloring matter represented by the general formula (1) is represented by the following general formula (2).

Wherein R _{11 to} R ₁₆ each independently represents a hydrogen atom or a substituent, and R ₁₃ and R ₁₄ or R ₁₅ and R ₁₆ may form a 5- or 6-membered ring, and L ₁₁ and L ₁₂ each independently represents an unsubstituted or substituted methine group, and Y ₁₁ and Y ₁₂ are each an oxygen atom, a sulfur atom, —CR ₁₇ R ₁₈ — or —NR _19- represents, and R ₁₇ , R ₁₈ and R ₁₉ each represents a hydrogen atom or a substituent.)
3. 3. The electrophotographic toner according to 1 or 2 above, which contains a metal complex compound represented by the following general formula (3).

General formula (3)
M (X1) _m (X2) _l · W1 _s
(In the formula, M represents a divalent ion of Ni, Co, Zn or Cu, X1 and X2 each independently represent a monodentate or bidentate ligand, and may be the same or different; And X2 may be linked, m and l each represent an integer of 0 to 2. W1 represents a counter ion when a counter ion is required to neutralize the charge, and s represents 0 or 1 To express.)
4). 4. The electrophotographic toner according to 3 above, wherein at least one of X1 and X2 in the general formula (3) is represented by the following general formula (4).

(In the formula, E ₁ represents a substituent, E ₂ represents an electron-withdrawing group having a Hammett substituent constant (σp) of 0.1 to 0.9, and R represents an alkyl group, an aryl group, or a heterocyclic group. Represents an alkoxy group, an aryloxy group or an amino group, and may have a substituent.
5). In addition to the dye represented by the general formula (1), the dye represented by the general formula (2), or the dye represented by the general formula (1) or the general formula (2), the general formula (3) 5. The electrophotographic toner according to any one of 1 to 4 above, wherein colored fine particles containing a metal complex compound represented by formula (1) are dispersed in a thermoplastic resin.

  6). 6. The toner for electrophotography as described in 5 above, wherein the colored fine particles further contain a resin different from the thermoplastic resin.

  7). 7. The electrophotographic toner according to 5 or 6, wherein the colored fine particles have an average particle size of 10 nm or more and 100 nm or less.

  8). In an image forming method including at least a step of developing an electrostatic charge image formed on an electrostatic image bearing member with toner and a step of transferring a toner image formed by development onto a transfer material, An image forming method comprising using the electrophotographic toner according to any one of the above items.

  9. A squarylium dye characterized by being a dye represented by the following general formula (5).

Wherein R _{11 to} R ₁₆ each independently represents a hydrogen atom or a substituent, and R ₁₃ and R ₁₄ or R ₁₅ and R ₁₆ may form a 5- or 6-membered ring, and R ₁₁ and R ₁₂ are each an alkyl group having a total carbon number of 18 or more, and L ₁₁ and L ₁₂ each independently represent an unsubstituted or substituted methine group. Y ₁₁ and Y ₁₂ each represent an oxygen atom, a sulfur atom, —CR ₁₇ R ₁₈ — or —NR ₁₉ —, and each of R ₁₇ , R ₁₈ and R ₁₉ represents a hydrogen atom or a substituent.

  According to the present invention, an electrophotographic toner that can be favorably colored without causing dispersibility in a thermoplastic resin, and has excellent transparency, particularly color reproducibility, and excellent heat resistance, chargeability, and offset resistance. An image forming method using the toner for electrophotography, and a novel squarylium dye can be provided.

FIG. 3 is a diagram schematically illustrating a cross section of toner particles in which colored fine particles are dispersed in a thermoplastic resin. It is the figure which represented typically the cross section of the colored fine particle of a core shell structure formed by coat | covering an inside (core) with outer shell resin (shell). It is an absorption waveform in ethyl acetate of D-22. It is an absorption waveform in ethyl acetate of D-23.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Toner particle 2 Thermoplastic resin 3 Colored fine particle 4 Resin 5 Dye 6 Inside (core)
7 Outer shell resin (shell)

  The electrophotographic toner of the present invention is characterized by containing a dye having a specific structure in a thermoplastic resin, and the dispersion form of the dye is nano-order dye fine particles (colored fine particles). It is characterized by that.

  As a result of intensive studies to solve the above problems, the present inventors have found that the dyes represented by the general formulas (1) and (2) and the metal complexes represented by the general formula (3) The present inventors have found a compound, and have found that a color toner in which colored fine particles containing the pigment and the metal complex compound are dispersed in a thermoplastic resin further exhibits excellent hue and image fastness.

  Hereinafter, the structures represented by the general formulas (1) to (4) will be described.

<< Compound Represented by Formula (1) >>
In the general formula (1), Q ₁ and Q ₂ represent an atomic group necessary for forming a 5-membered or 6-membered nitrogen-containing heterocycle, which may be condensed or have a substituent. . L _{1 to} L ₁₀ each independently represents an unsubstituted or substituted methine group, and R ₁ and R ₂ represent a substituent. m1, m2, n1, and n2 represent 0 or 1.

Preferred examples of the heterocycle formed by Q ₁ and Q ₂ include benzothiazole nucleus, benzoxazole nucleus, benzoselenazole nucleus, benzotelrazole nucleus, 2-quinoline nucleus, 4-quinoline nucleus, benzimidazole nucleus, thiazoline. Nucleus, indolenine nucleus, oxadiazole nucleus, thiazole nucleus, imidazole nucleus and the like, and condensed rings include pyridine ring, thiophene ring, etc. in addition to benzene ring, more preferably benzothiazole nucleus, benzoxazole nucleus Benzimidazole nucleus, benzoselenazole nucleus, 2-quinoline nucleus, 4-quinoline nucleus, indolenine nucleus, particularly preferably benzothiazole nucleus, benzoxazole nucleus, 2-quinoline nucleus, 4-quinoline nucleus, indolenine nucleus. It is.

  Examples of substituents on the ring include carboxylic acid, phosphonic acid, sulfonic acid, halogen (F, Cl, Br, I), cyano, alkoxy (methoxy, ethoxy, isopropoxy, methoxyethoxy, etc.), aryloxy (phenoxy, etc.) , Alkyl (methyl, ethyl, t-butyl, cyclopropyl, cyclohexyl, trifluoromethyl, methoxyethyl, allyl, benzyl, etc.), alkylthio (methylthio, ethylthio, etc.), alkenyl (vinyl, 1-propenyl, etc.), aryl (Phenyl, thienyl, toluyl, chlorophenyl, etc.).

In General formula (1), L < ₁ > -L < ₁₀ > represents the methine group which may have a substituent each independently. Examples of the substituent include a substituted or unsubstituted alkyl group (preferably having 1 to 12 carbon atoms, more preferably 1 to 7 carbon atoms, such as methyl, ethyl, propyl, isopropyl, cyclopropyl, butyl, 2- Carboxyethyl, benzyl, etc.), substituted or unsubstituted aryl groups (preferably having 6 to 10 carbon atoms, more preferably 6 to 8 carbon atoms such as phenyl, toluyl, chlorophenyl, o-carboxyphenyl), A ring group (eg, pyridyl, thienyl, furanyl, pyridyl, barbituric acid), a halogen atom (eg, chlorine, bromine), an alkoxy group (eg, methoxy, ethoxy), an amino group (preferably having 1 to 12 carbon atoms, More preferably 6 to 12, for example, diphenylamino, methylphenyl Mino, 4-acetyl-piperazin-1-yl), oxo group, and the like. These substituents on the methine group may be linked to each other to form a ring such as a cyclopentene ring, a cyclohexene ring, or a squarylium ring, or may form a ring with an auxiliary color group.

In the general formula (1), R ₁₁ and R ₁₂ represent a substituent. The substituent is preferably an aromatic group which may have a substituent, or an aliphatic group which may have a substituent, and the aromatic group preferably has 1 to 16 carbon atoms, more preferably 5 or 6. The number of carbon atoms of the aliphatic group is preferably 1 to 18, more preferably 4 to 18, but the total number of carbon atoms of R ₁₁ and R ₁₂ is more preferably 17 or more. Examples of the unsubstituted aliphatic group and aromatic group include methyl group, ethyl group, n-propyl group, n-butyl group, n-octyl group, n-decyl group, i-hexadecyl group, phenyl group, and naphthyl group. Is mentioned.

The substituent that Q ₁ and Q ₂ may have in the general formula (1) is not particularly limited as long as it can be substituted, but an alkyl group (for example, a methyl group, an ethyl group, a propyl group, isopropyl) Group, t-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, trifluoromethyl group, etc.), cycloalkyl group (for example, cyclopentyl group, cyclohexyl group etc.), alkenyl Group (for example, vinyl group, allyl group, etc.), alkynyl group (for example, ethynyl group, propargyl group, etc.), aryl group (for example, phenyl group, naphthyl group, etc.), heteroaryl group (for example, furyl group, thienyl group, etc.) Pyridyl group, pyridazyl group, pyrimidyl group, pyrazyl group, triazyl group, imidazolyl group, pyrazolyl group, thiazo Aryl group, benzimidazolyl group, benzoxazolyl group, quinazolyl group, phthalazyl group, etc.), heterocyclic group (also called heterocyclic group, for example, pyrrolidyl 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, etc.), cycloalkoxy group (for example, cyclopentyloxy group, cyclohexyloxy group, etc.), aryloxy group (for example, , Phenoxy group, naphthyloxy group, etc.), alkylthio group (eg, methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (eg, cyclopentylthio group, cyclo Xylthio group, etc.), arylthio group (eg, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.) An aryloxycarbonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), a sulfamoyl group (eg, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexyl) Aminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminos Phonyl groups, etc.), acyl groups (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 (eg acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group etc.), amide group (eg methylcarbonyl) Amino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexyl Silcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl 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, phenylurea Id group, naphthylureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl 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, 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, etc., cyano group, nitro group, halogen atom (for example, fluorine atom, chlorine atom, bromine atom, etc.) ) And the like. These may be further substituted with the same substituent.

  Of these, alkyl groups, aryl groups, heterocyclic groups, heteroaryl groups, alkoxy groups, sulfamoyl groups, ureido groups, amino groups, amide groups, acyl groups, alkoxycarbonyl groups, carbamoyl groups, cyano groups, halogens are preferred. An atom etc. are mentioned, More preferably, they are an alkyl group, an aryl group, an alkoxy group, a carbamoyl group, a cyano group, an amide group, and a halogen atom.

  In the general formula (1), m1, m2, n1 and n2 represent 0 or 1, but m1 and n1 are preferably 0 for ease of synthesis, and m2 and n2 are 0 from the point of the absorption waveform of the dye. Although it is preferable, it is not the limitation from the point of adjustment of absorption wavelength.

<< Compound Represented by Formula (2) >>
In the general formula (2), R _{11 to} R ₁₆ each independently represent a hydrogen atom or a substituent, and R ₁₃ and R ₁₄ or R ₁₅ and R ₁₆ may form a 5- or 6-membered ring. It may have a substituent. L ₁₁ and L ₁₂ each independently represent an unsubstituted or substituted methine group. Y ₁₁ and Y ₁₂ each independently represent an oxygen atom, a sulfur atom, —CR ₁₇ R ₁₈ — or —NR ₁₉ —, and R ₁₇ , R ₁₈ and R ₁₉ each represent a hydrogen atom or a substituent.

In the general formula (2), the substituent represented by R ₁₁ and R ₁₂ has the same meaning as R ₁ and R ₂ in the general formula (1), and the same applies to the preferred range.

In the general formula (2), the substituent represented by R _{13 to} R ₁₆ has the same meaning as the substituent that Q ₁ or Q ₂ in the general formula (1) may have, and a preferable substituent thereof. As hydrogen atom, alkyl group, aryl group, heterocyclic group, heteroaryl group, alkoxy group, sulfamoyl group, ureido group, amino group, amide group, acyl group, alkoxycarbonyl group, carbamoyl group, cyano group, halogen atom, etc. More preferred are alkyl groups, aryl groups, alkoxy groups, cyano groups, and halogen atoms. R ₁₃ and R ₁₄ or R ₁₅ and R ₁₆ may form a 5- or 6-membered ring, and preferably form a benzene ring.

In the general formula (2), Y ₁₁ and Y ₁₂ may be the same or different and are preferably an oxygen atom, a sulfur atom, or —CR ₁₇ R ₁₈ —, and R ₁₇ and R ₁₈ are the above general formulas. It is synonymous with the substituent which Q < ₁ > or Q < ₂ > in (1) may have, The preferable substituent is a hydrogen atom, an alkyl group, and an aryl group, and also having a substituent is also preferable. .

In the general formula (2), L ₁₁ and L ₁₂ each independently represent an unsubstituted or substituted methine group, preferably unsubstituted, but when having a substituent, an alkyl group, aryl group, halogen An atom, an alkoxycarbonyl group, a carbamoyl group, or a cyano group is preferable.

The compound represented by the general formula (2) is preferably an alkyl group in which the total number of carbon atoms of R ₁₁ and R ₁₂ represented by the general formula (5) is 18 or more. Is preferably an alkyl group having 18 to 36 carbon atoms in total.

<< Compound Represented by Formula (3) >>
In the general formula (3), M represents a divalent ion of Ni, Co, Zn or Cu, and X1 and X2 each independently represent a monodentate or bidentate ligand, which may be the same or different. In addition, X1 and X2 may be linked. m and l represent an integer of 0-2. W1 represents a counter ion when a counter ion is required to neutralize the charge.

  M is preferably Ni, Co and Cu, more preferably Ni and Cu.

  Examples of X1 and X2 are described in JP-A Nos. 2000-251957, 2000-31723, 2000-323191, 2001-6760, 2001-59062, and 2001-60467. What is being done.

  Specifically, halogen ion, hydroxide ion, ammonia, pyridine, amine (for example, methylamine, diethylamine, tributylamine, etc.), cyanide ion, cyanate ion, thiolate ion, thiocyanate ion, and bipyridines, amino Various chelate ligands such as polycarboxylic acids, 8-hydroxyquinoline and the like are exemplified, and chelate ligands are exemplified in “Chelical Chemistry” by Keihei Ueno.

  As a monodentate ligand, a coordination coordinated by an acyl group, a carbonyl group, a thiocyanate group, an isocyanate group, a cyanate group, an isocyanate group, a halogen atom, a cyano group, an alkylthio group, an arylthio group, an alkoxy group or an aryloxy group A ligand or a ligand composed of dialkyl ketone or carbonamide is preferred.

  Examples of the bidentate ligand include acyloxy group, oxalylene group, acylthio group, thioacyloxy group, thioacylthio group, acylaminooxy group, thiocarbamate group, dithiocarbamate group, thiocarbonate group, dithiocarbonate group, and trithiocarbonate. A ligand coordinated by an nate group, an alkylthio group or an arylthio group, or a ligand composed of a dialkyl ketone or a carbonamide is preferred.

  Specific examples are shown below, but the present invention is not limited thereto. It should be noted that the structural formula shown here is only one limit structure among a number of possible resonance structures, and the distinction between a covalent bond (indicated by −) and a coordination bond (indicated by...) Is also formal. It does not represent an absolute distinction.

  Next, general formula (4) preferable as a ligand will be described.

In the general formula (4), E ₁ represents a substituent, E ₂ represents an electron withdrawing group having a Hammett substituent constant (σp) of 0.1 to 0.9, and R represents an alkyl group, an aryl group, a complex It represents a cyclic group, an alkoxy group, an aryloxy group or an amino group, and may have a substituent.

Examples of the substituent represented by E ₁ and E ₂ include the group described in the general formula (1), and the substituent having a σp value of 0.1 or more and 0.9 or less will be described below.

  As the value of Hammett's substituent constant σp here, Hansch, C .; It is preferable to use the values described in the report of Leo et al. (For example, J. Med. Chem. 16, 1207 (1973); ibid. 20, 304 (1977)).

  For example, as a substituent or atom having a value of σp of 0.10 or more, a chlorine atom, a bromine atom, an iodine atom, a carboxyl group, a cyano group, a nitro group, a halogen-substituted alkyl group (for example, trichloromethyl, trifluoromethyl, Chloromethyl, trifluoromethylthiomethyl, trifluoromethanesulfonylmethyl, perfluorobutyl), aliphatic, aromatic or heterocyclic acyl groups (eg formyl, acetyl, benzoyl), aliphatic, aromatic or heterocyclic sulfonyl groups (eg , Trifluoromethanesulfonyl, methanesulfonyl, benzenesulfonyl), carbamoyl group (eg, carbamoyl, methylcarbamoyl, phenylcarbamoyl, 2-chloro-phenylcarbamoyl), alkoxycarbonyl group (eg, methoxycarbonyl, Toxylcarbonyl, diphenylmethylcarbonyl), substituted aromatic groups (for example, pentachlorophenyl, pentafluorophenyl, 2,4-dimethanesulfonylphenyl, 2-trifluoromethylphenyl), heterocyclic residues (for example, 2-benzooxa Zolyl, 2-benzthiazolyl, 1-phenyl-2-benzimidazolyl, 1-tetrazolyl), azo group (eg, phenylazo), ditrifluoromethylamino group, trifluoromethoxy group, alkylsulfonyloxy group (eg, methanesulfonyloxy) ), Acyloxy groups (for example, acetyloxy, benzoyloxy), arylsulfonyloxy groups (for example, benzenesulfonyloxy), phosphoryl groups (for example, dimethoxyphosphonyl, diphenylphosphoryl), sulfamoyl groups ( For example, N-ethylsulfamoyl, N, N-dipropylsulfamoyl, N- (2-dodecyloxyethyl) sulfamoyl, N-ethyl-N-dodecylsulfamoyl, N, N-diethylsulfamoyl) Is mentioned.

  In addition, as a substituent having a σp value of 0.35 or more, a cyano group, a nitro group, a carboxyl group, a fluorine-substituted alkyl group (for example, trifluoromethyl, perfluorobutyl), aliphatic, aromatic or heterocyclic acyl Groups (eg acetyl, benzoyl, formyl), aliphatic, aromatic or heterocyclic sulfonyl groups (eg trifluoromethanesulfonyl, methanesulfonyl, benzenesulfonyl), carbamoyl groups (eg carbamoyl, methylcarbamoyl, phenylcarbamoyl, 2- Chloro-phenylcarbamoyl), alkoxycarbonyl groups (eg, methoxycarbonyl, ethoxycarbonyl, diphenylmethylcarbonyl), fluorine or sulfonyl group substituted aromatic groups (eg, pentafluorophenyl, 2,4-dimethanesulfonate) Phenyl), heterocyclic residues (eg 1-tetrazolyl), azo groups (eg phenylazo), alkylsulfonyloxy groups (eg methanesulfonyloxy), phosphoryl groups (eg dimethoxyphosphoryl, diphenylphosphoryl), sulfamoyl groups, etc. Is mentioned.

  Examples of the substituent having a value of σp of 0.60 or more include a cyano group, a nitro group, an aliphatic, aromatic or heterocyclic sulfonyl group (for example, trifluoromethanesulfonyl, difluoromethanesulfonyl, methanesulfonyl, benzenesulfonyl) and the like. It is done.

The substituent represented by E ₁ has the same meaning as R ₁₁ in the general formula (1), but is preferably an alkyl group, aryl group, heterocyclic group, carbonyl group, cyano group, alkoxycarbonyl group, alkylsulfonyl. Group, an alkylsulfonyloxy group, and the like, and an electron-withdrawing group is preferable.

Preferred examples of E ₁ and E ₂ include halogenated alkyl groups (particularly fluorine-substituted alkyl groups), carbonyl groups, cyano groups, alkoxycarbonyl groups, alkylsulfonyl groups, alkylsulfonyloxy groups, and the like.

  Preferable substituents for R include an alkyl group having 2 to 20 carbon atoms, an alkoxy group having 2 to 20 carbon atoms, an aryloxy group, and an amino group, and more preferably an alkyl group having 4 to 18 carbon atoms or a carbon number. 4 to 18 alkoxy groups and aryloxy groups. Most preferably, it is a C6-C16 alkoxy group.

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

  W1 represents the counterion when a counterion is required to neutralize the charge, for example whether a dye is a cation, an anion, or whether it has a net ionic charge, its metal, Depends on the ligand and substituent. When the substituent has a dissociable group, it may be dissociated and have a negative charge, and in this case as well, the charge of the entire molecule is neutralized by W1.

  Typical cations are inorganic or organic ammonium ions (eg, tetraalkylammonium ions, pyridinium ions), alkali metal ions and protons, while anions are specifically inorganic or organic anions. For example, a halogen anion (for example, fluoride ion, chloride ion, bromide ion, iodide ion), substituted aryl sulfonate ion (for example, p-toluene sulfonate ion, p-chlorobenzene sulfonate) Ions), aryl disulfonate ions (for example, 1,3-benzenedisulfonate ions, 1,5-naphthalenedisulfonate ions, 2,6-naphthalenedisulfonate ions), alkyl sulfate ions (for example, methyl sulfate ions), sulfuric acid Ion, ion thiocyanate , Perchlorate ion, tetrafluoroborate ion, hexafluorophosphate ion, picrate ion, acetate ion, trifluoromethanesulfonate ion, and the like.

  It is preferable to use the compound represented by the general formula (3) because the dispersion stability is improved and the storage stability (light resistance) is also improved.

  The addition amount of the compound represented by the general formula (3) is preferably 0.5 to 3 times moles, more preferably 0.5 to 2 times moles of the dye. However, if the amount is less than 0.5 times mole, the light resistance may be remarkably lowered. If the amount is more than 3 times mole, the dispersion stability of the colored fine particles may be lowered, which may adversely affect the toner formation.

  Examples of such copper compounds include copper acetate, copper stearate, copper 2-ethylhexanoate, copper sulfate, and cupric chloride as readily available compounds as commercially available products, and examples of nickel compounds include acetic acid. Although nickel, nickel stearate, nickel 2-ethylhexanoate etc. are mentioned, it is not limited to them.

  Specific compounds are listed below, but the present invention is not limited thereto.

  Although the typical example represented with the said General formula (1) and (2) below is given below, this invention is not limited to this.

  The dyes represented by the general formulas (1) and (2) can have the following structural isomers on the left and right via squaric acid, and the structures shown below are represented by any one of these structures.

  The coloring matter represented by the general formulas (1) and (2) according to the present invention is, for example, a method described in pages 85 to 107 of a dye and pigment (Dyes & Pigments) September 1988, JP-A-6-287210. No. 7-25153, JP-A 2000-160042, 2000-345059, 2001-117201, etc. The ligands of the metal complex compounds represented by (3) and (4) can be synthesized with reference to JP-A Nos. 2002-332259 and 2003-237246.

  Specific examples of methods for synthesizing the dyes represented by the general formulas (1) and (2) are shown below, but other compounds can be synthesized in the same manner. It is not limited to.

  (Synthesis Example 1: Synthesis of D-22)

  40 ml of toluene was added to Intermediate 5, 4.45 g and Intermediate 2, 0.46 g, and the mixture was heated to reflux for 8 hours while dehydrating through an ester tube. The reaction solution was cooled and purified by column chromatography to obtain D-22, 2.00 g. The product was identified by MASS, H-NMR and IR spectra, and confirmed to be the target product. The absorption maximum wavelength in ethyl acetate was 654 nm (half width: 29 nm). FIG. 3 shows an absorption waveform of D-22 in ethyl acetate.

  (Synthesis Example 2: Synthesis of D-23)

  200 ml of 1-butanol, 14.2 g of triethylamine and 17.42 g of Intermediate 3 were added to 37.08 g of Intermediate 1, and the reaction was conducted by heating at 60 ° C. for 6 hours, followed by concentration and purification by column chromatography. Next, the concentrate was dissolved in 400 ml of acetone, 6M-HCl and 120 ml were added, and the mixture was heated to reflux for 10 hours. The reaction mixture is concentrated, extracted with 300 ml of ethyl acetate and concentrated again. Purification by column chromatography gave Intermediate 4, 25.7 g. It was identified by MASS, H-NMR, and IR spectrum, and confirmed to be the target product.

  70 ml of toluene was added to Intermediate 4, 4.08 g and Intermediate 5, 5.01 g, and the mixture was heated to reflux for 6 hours while dehydrating through an ester tube. The reaction solution was cooled and purified by column chromatography to obtain D-23, 3.81 g. The product was identified by MASS, H-NMR and IR spectra, and confirmed to be the target product. The absorption maximum wavelength in ethyl acetate was 645 nm (half width: 30 nm). FIG. 4 shows an absorption waveform of D-23 in ethyl acetate.

(Dye dispersion method)
The toner for electrophotography of the present invention is prepared 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. , And 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. 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 dye solid dispersions, and the repulsive force of the particle surface produced by pH adjustment and the cohesive force due to the addition of electrolyte The toner particles are produced by slowly agglomerating while maintaining the balance, and performing aggregation while controlling the particle size and particle size distribution, and simultaneously controlling the fusion and shape between the fine particles by heating and stirring.

  In the case of 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. It can be created by the same method. That is, it can 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 are characterized by containing at least a dye represented by the general formula (1) or (2), or further a metal complex compound, and are colored by using a dispersion method such as a submerged drying method described later. The dispersed particle size of the fine particles can be controlled. Further, it is preferable to further contain a resin having a composition different from that of the thermoplastic resin. Instead of directly dispersing or dissolving the dye in a toner binder resin generally known as a toner using the above-mentioned dye. The colored fine particles can be dispersed in the 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. Further, as shown in FIG. 2, the electrophotographic toner of the present invention may have colored fine particles coated with an outer shell resin (shell). In this case, the resin and thermoplastic resin constituting the inside (core) of the colored fine particles are used. If there is no restriction on the combination of resin (binder resin), the degree of freedom of material is large, and only the outer shell resin (shell) is the same for four color toners (yellow, magenta, cyan, black), the same Since it can be manufactured under manufacturing conditions, there is a great cost advantage. 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)
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 are obtained by, for example, dissolving (or dispersing) a pigment (or pigment and resin, additive, etc.) in an organic solvent, emulsifying and dispersing in water, and then removing the organic solvent (drying in liquid If the resin is added before emulsification and dispersion to remove the organic solvent to form primary particles, and the resin is further added and coated with an outer shell resin (shell), A colored fine particle having a core-shell structure can be obtained by adding a monomer having a polymerizable unsaturated double bond, performing 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 with 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.

(Core shell structure)
In the present invention, the core-shell structure means a form in which two or more kinds of resins or dyes having different compositions are present in phase separation in the particles. Therefore, the shell portion may not only cover the core portion completely, but may cover a portion of the core portion. Further, a part of the resin forming the shell may form a domain or the like in the core particle. Furthermore, it may have a multilayer structure of three or more layers including another layer having a different composition in the middle between the core part and the shell part.

  In the present invention, the colored fine particles form a core-shell structure, and the colored portion formed by the resin and / or the high-boiling organic solvent and the dye in the colored fine particles is used as a core, and this is further coated with an outer shell resin. A shell and a core-shell structure are preferable.

(Core resin)
The resin forming the inside (core) of the colored fine particles according to the present invention will be described. The resin used for the inside (core) of the colored fine particles according to the present invention is not particularly limited as long as it has a composition different from that of the thermoplastic resin. For example, a (meth) acrylate resin, a polyester resin, a polyamide resin, Polyimide resin, polystyrene resin, polyepoxy resin, polyester resin, amino resin, fluorine resin, phenol resin, polyurethane resin, polyethylene resin, polyvinyl chloride resin, polyvinyl alcohol resin, polyether Resin, polyether ketone resin, polyphenylene sulfide resin, polycarbonate resin, aramid resin, etc., (meth) acrylate resin, polystyrene resin, polyethylene resin, polyvinyl chloride resin, polyvinyl alcohol Polymerizable ethylenic resin The resulting resin is preferably by polymerizing a sexual unsaturated double bond. Most preferred are (meth) acrylate resins and polystyrene resins.

  The (meth) acrylate resin is synthesized by homopolymerizing or copolymerizing various methacrylate monomers or acrylate monomers, and by changing the monomer species and the monomer composition ratio, the desired (meth) acrylate is obtained. System resin can be obtained. Further, in the present invention, it can be used by copolymerizing together with a copolymerizable monomer having an unsaturated double bond other than the (meth) acrylate monomer together with the (meth) acrylate monomer. Can be used by mixing a plurality of other resins together with the poly (meth) acrylate resin. It is also preferable to improve the compatibility with the dye by using a high-boiling organic solvent described later and a resin in combination.

  Examples of the monomer component forming the (meth) acrylate resin used in the present invention include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, and butyl (meth) acrylate. , Isopropyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, stearyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, acetoacetoxyethyl (meth) acrylate, dimethylaminoethyl (meth) Acrylate, 2-hydroxypropyl (meth) acrylate, di (ethylene glycol) ethyl ether (meth) acrylate, ethylene glycol methyl ether (meth) acrylate, isobonyl (meth) acrylate Ethyltrimethylammonium chloride (meth) acrylate, trifluoroethyl (meth) acrylate, octafluoropentyl (meth) acrylate, 2-acetamidomethyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-dimethylaminoethyl (Meth) acrylate, 3-trimethoxysilanepropyl (meth) acrylate, benzyl (meth) acrylate, tridecyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, dodecyl (meth) acrylate , Octadecyl (meth) acrylate, 2-diethylaminoethyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, phenyl (Meth) acrylate, glycidyl (meth) acrylate and the like can be mentioned, but (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, stearyl ( They are meth) acrylate, 2-hydroxyethyl (meth) acrylate, acetoacetoxyethyl (meth) acrylate, benzyl (meth) acrylate, tridecyl (meth) acrylate, dodecyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate.

  Polystyrene resins include homopolymers of styrene monomers, or random copolymers, block copolymers, and graft copolymers obtained by copolymerizing monomers with other unsaturated double bonds that can be copolymerized with styrene monomers. Can be mentioned. Furthermore, blends and polymer alloys obtained by blending such polymers with other polymers are also included. Examples of the styrene monomer include styrene, α-methylstyrene, α-ethylstyrene, α-methylstyrene-p-methylstyrene, o-methylstyrene, m-methylstyrene, and p-methylstyrene. , O-chlorostyrene, m-chlorostyrene, p-chlorostyrene, p-bromostyrene, dichlorostyrene, dibromostyrene, trichlorostyrene, tribromostyrene, and the like. Α-methylstyrene is preferred.

  Resins used in the present invention are synthesized by homopolymerization or copolymerization of these, for example, copolymer resins such as benzyl methacrylate / ethyl acrylate or butyl acrylate, and copolymers such as methyl methacrylate / 2-ethylhexyl methacrylate. Polymer resin, copolymer resin of methyl methacrylate / methacrylic acid / stearyl methacrylate / acetoacetoxyethyl methacrylate, copolymer resin of styrene / acetoacetoxyethyl methacrylate / stearyl methacrylate, styrene / 2-hydroxyethyl methacrylate / stearyl Examples thereof include a copolymer of methacrylate and a copolymer resin such as 2-ethylhexyl methacrylate / 2-hydroxyethyl methacrylate.

  The resin used in the present invention preferably has a number average molecular weight of 500 to 100,000, particularly 1,000 to 30,000 from the viewpoint of durability and fine particle formability.

(Methacrylic resin)
In the present invention, the outer shell resin that covers the outer shell of the colored fine particles to form the shell is not particularly limited. For example, poly (meth) acrylate resin, polyester resin, polyamide resin, polyimide resin, Polystyrene resins, polyepoxy resins, polyester resins, amino resins, fluorine resins, phenol resins, polyurethane resins, polyethylene resins, polyvinyl chloride resins, polyvinyl alcohol resins, polyarylate resins, poly Examples thereof include ether resins, polyether ketone resins, polyphenylene sulfide resins, polycarbonate resins, and aramid resins. In particular, from the viewpoint of combination with toner binder resin (thermoplastic resin), poly (meth) acrylate is preferable. Resin.

  The poly (meth) acrylate resin is synthesized by homopolymerizing or copolymerizing various (meth) acrylate monomers, and by changing the monomer species and the monomer composition ratio, the desired poly (meth) acrylate resin A resin can be obtained. In the present invention, a plurality of other resins can be mixed together with the poly (meth) acrylate resin.

  Examples of the monomer component forming the poly (meth) acrylate resin used in the present invention include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, and butyl (meth). Acrylate, isopropyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, stearyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, acetoacetoxyethyl (meth) acrylate, dimethylaminoethyl (meta ) Acrylate, 2-hydroxypropyl (meth) acrylate, di (ethylene glycol) ethyl ether (meth) acrylate, ethylene glycol methyl ether (meth) acrylate, isobornyl (meth) acrylate Rate, ethyltrimethylammonium chloride (meth) acrylate, trifluoroethyl (meth) acrylate, octafluoropentyl (meth) acrylate, 2-acetamidomethyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-dimethylaminoethyl (Meth) acrylate, 3-trimethoxysilanepropyl (meth) acrylate, benzyl (meth) acrylate, tridecyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, dodecyl (meth) acrylate , Octadecyl (meth) acrylate, 2-diethylaminoethyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, Nyl (meth) acrylate, glycidyl (meth) acrylate, etc. are mentioned, but (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, stearyl are preferred. (Meth) acrylate, 2-hydroxyethyl (meth) acrylate, acetoacetoxyethyl (meth) acrylate, benzyl (meth) acrylate, tridecyl (meth) acrylate, dodecyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate. Preferred are methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, and butyl (meth) acrylate.

  Further, the outer shell resin in the present invention may be a copolymer with a reactive emulsifier.

(Reactive emulsifier)
The reactive emulsifier preferably used in the present invention may be any of anionic and nonionic reactive emulsifiers, but compounds having the following A, B, or C substituents are preferred.

A: a linear alkyl group, a branched alkyl group, or a substituted or unsubstituted aromatic group having a total carbon number of 6 or more B: a nonionic substituent or anionic substituent that speaks for surface activity C: A polymerizable group capable of radical polymerization.

  Examples of the linear alkyl group described in the section A include a heptyl group, an octyl group, a nonyl group, a decyl group, a dodecyl group, and the like, and examples of the branched alkyl group include a 2-ethylhexyl group, Examples of the aromatic group include a phenyl group, a nonylphenyl group, and a naphthyl group.

  Examples of the nonionic substituent or anionic substituent that expresses the emulsifying ability (surfactant ability) described in Item B include polyethylene oxide, polypropylene oxide, polyalkylene oxide of a copolymer thereof, and the like. Specific examples of the anionic substituent include carboxylic acid, phosphoric acid, sulfonic acid, and salts thereof. Moreover, it is one of the specific examples of an anionic group that the above-mentioned anionic group was substituted at the terminal of alkylene oxide. The substituent represented by the item B is preferably an anionic group, and more preferably a terminal terminal is a salt.

  The radically polymerizable group described in the item C is a group that undergoes polymerization or crosslinking reaction by radically active species. For example, a vinyl group having an ethylenically unsaturated bond, an allyl group, a 1-propenyl group, an isotopic group, Examples include propenyl group, acrylic group, methacryl group, maleimide group, acrylamide group, styryl group and the like.

  As the reactive emulsifier used in the present invention, compounds represented by the following general formulas (A) to (C) are preferable.

In the general formula (A), R ₁ represents a linear alkyl group having 6 to 20 carbon atoms, a branched alkyl group, or a substituted or unsubstituted aromatic group. For example, heptyl group or octyl group described in the above section A Group, nonyl group, decyl group, linear alkyl group such as dodecyl group, branched alkyl group such as 2-ethylhexyl group, aromatic group such as phenyl group, nonylphenyl group, naphthyl group, and the like.

R ₂ represents a substituent having a polymerizable group capable of radical polymerization, and examples thereof include an acrylic group, a methacryl group, and a maleimide group, which are ethylenically unsaturated bonds described in the above section C. Y ₁ represents a sulfonic acid, a carboxylic acid, or a salt thereof.

  The compound represented by the general formula (A) can be synthesized by a person skilled in the art by a known method. Moreover, it can obtain easily from a commercial item, for example, "Ramtel S-120" and "Ramtel S-120A" by Kao Corporation. Examples thereof include “RAMTEL S-180”, “RAMTEL S-180A”, “ELEMINOL JS-2” manufactured by Sanyo Chemical Industries, Ltd.

In the general formula (B), R ₃ has the same meaning as R _{1 in the} general formula (A), and R ₄ in the general formula (B) has the same meaning as R _{2 in the} general formula (A). . Y ₂ represents a hydrogen atom, a sulfonic acid, a carboxylic acid, or a salt thereof. AO represents an alkylene oxide.

  The compound represented by the general formula (B) can be synthesized by a person skilled in the art by a known method. Moreover, it can be easily obtained from a commercial product, for example, NE series such as “Adekaria soap NE-10”, “Adekaria soap NE-20”, “Adekaria soap NE-30” manufactured by Asahi Denka Kogyo Co., Ltd. SE series such as “Adekaria soap SE-10N”, “Adekaria soap SE-20N”, “Adekaria soap SE-30N”, “Aqualon RN-10”, “Aquaron RN-” manufactured by Daiichi Kogyo Seiyaku Co., Ltd. RN series such as “20”, “AQUALON RN-30”, “AQUALON RN-50”, “AQUALON HS-05”, “AQUALON HS-10”, “AQUALON HS-20”, “AQUALON HS-30”, etc. Examples include the HS series or the Aqualon BC series.

In the general formula (C), R ₅ has the same meaning as R _{1 in the} general formula (A), R _{6 in the} general formula (C) has the same meaning as R _{2 in the} general formula (A), and Y _{3 in the} general formula (C) has the same meaning as Y _{1 in the} general formula (A), and AO in the general formula (C) has the same meaning as AO in the general formula (B).

  The compound represented by the general formula (C) can be synthesized by a person skilled in the art by a known method. Moreover, it can obtain easily from a commercial item, for example, "AQUALON KH-05", "AQUALON KH-10", "AQUALON KH-20", etc. by Dai-ichi Kogyo Seiyaku Co., Ltd. can be mentioned.

  In the general formulas (B) and (C), the average degree of polymerization n of the alkylene oxide chain (AO) is preferably 1 to 10, for example, “AQUALON KH-05” manufactured by Daiichi Kogyo Seiyaku Co., Ltd. , “AQUALON KH-10”, “AQUALON HS-05”, “AQUALON HS-10”, and the like.

  In the present invention, the reactive emulsifier is preferably anionic. For example, the above-mentioned “Adekaria soap SE series” (Asahi Denka Kogyo Co., Ltd.), “Aqualon HS series” (Daiichi Kogyo Seiyaku Co., Ltd.) , “Latemul S series” (manufactured by Kao Corporation), “Eleminol JS series” (manufactured by Sanyo Chemical Industries), and the like.

  In the present invention, the reaction emulsifier is used in a total amount of about 100 parts by mass of the resin forming the colored fine particles according to the present invention, generally 0.1 to 80 parts by mass, preferably 1 to 70 parts by mass, Particularly preferably, 10 to 60 parts by mass are used.

(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 conventional 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. Polyoxyethylene higher fatty acid esters, glycerin higher fatty acid esters such as oleic acid monoglyceride, stearic acid monoglyceride, Shiechiren - polyoxypropylene - may be mentioned block copolymers or the like.

  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, and polyethoxyethylene lauryl ether. Polyoxyethylene alkyl ether sulfates such as sodium sulfate, polyoxyethylene alkylaryl ether sulfates such as sodium polyoxyethylene nonylphenyl ether sulfate, sodium monooctyl sulfosuccinate, sodium dioctyl sulfosuccinate, polyoxyethylene lauryl sulfosuccinic acid Examples thereof include alkylsulfosuccinic acid ester salts such as sodium, and derivatives thereof.

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

  The dyes represented by the general formulas (1) and (2) according to the present invention may be used alone or in combination with other dyes, and generally known dyes are used as the dyes used together. However, in the present invention, the coloring material 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, VariFast 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 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, Mitsui Chemicals MS Yellow HD-180, MS Red G, MS Msgenta HM-1450H, MS Blue HM-1384, Sumitomo Chemical ES Red 3001, ES Red 3002 , 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.

  In addition, as oil-soluble dyes, azomethine dyes derived from couplers such as cyclic methylene compounds such as phenol, naphthols, pyrazolones and pyrazolotriazoles, and open-chain methylene compounds, indoaniline dyes and the like are also preferably used.

(Particle size)
The colored fine particles, which are a preferred form 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 colored fine particles in the polymer is reduced, the stability of the colored fine particles tends to deteriorate, and the storage stability tends to deteriorate. On the other hand, if the particle size is larger than 1 μm, sedimentation tends 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, laser diffraction method, centrifugal sedimentation method, FFF method, electrical detector method, etc., but 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 ability to protect the colorant by the resin can be achieved. In addition, since the storage stability as a fine particle dispersion is excellent, an increase in particle size due to aggregation or the like can be prevented.

(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.

  Further, as an image stabilizer for improving the storage stability of the dye, for example, compounds described and cited on pages 10 to 13 of JP-A-8-29934 may be added, and commercially available phenols may be added. Examples of such compounds include amine, amine, sulfur, and phosphorus 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, barium sulfate, etc., but organic ultraviolet absorbers are preferred, and ultraviolet absorbers have a transmittance of 50%. The wavelength of is preferably 350 to 420 nm, more preferably 360 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 The thermoplastic resin contained in the toner for electrophotography of the present invention is preferably a thermoplastic resin having high adhesion to colored fine particles, which is one of the preferred forms, and is particularly soluble in a solvent. Are preferred. 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 toner can be applied without particular limitation. For example, styrene resins, acrylic resins such as alkyl acrylates and alkyl methacrylates, styrene acrylic copolymers Resins, polyester resins, silicone resins, olefin resins, amide resins, or epoxy resins are preferably used, but they have high transparency and high melting properties in order to improve transparency and color reproducibility of superimposed images. However, a resin having a low viscosity and a high sharp melt property is 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 (folded fixing property is deteriorated). The meltability is lowered and the fixing strength is lowered. Further, if Mw / Mn is less than 2, high temperature offset is likely to occur, and if it is greater than 6, sharp melt characteristics at the time of fixing are lowered, and toner translucency and color mixing at the time of full color image formation are lowered. 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, kneading / pulverizing method, suspension polymerization method, emulsion polymerization method, emulsion dispersion granulation. It can be produced by other known methods such as a 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.

  In the emulsion polymerization method, a 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 generated 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 preferably used after being surface-treated with a silane coupling agent, a titanium coupling agent, a higher fatty acid, silicone oil, etc. from the viewpoint of environmental stability and heat-resistant storage stability. 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 in which such magnetic particles are coated with a resin, or a binder-type carrier in which magnetic fine powder is dispersed 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. 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. Further, 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 fog.

(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 the photoconductor and transferring them in a batch, a method of sequentially transferring the images formed on the photoconductor to a transfer belt, etc. are not particularly limited, but more preferably a plurality of images on the photoconductor In this method, an image is formed and transferred in a batch.

  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 photoreceptor 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 onto paper or the like to form an image. Therefore, unlike the so-called intermediate transfer method, the number of times of transfer that causes image disturbance is one time. 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.

  Further, 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 coated with a resin, or a so-called resin dispersion type carrier in which magnetic particles are dispersed in a resin. The resin composition for coating is not particularly limited, and for example, olefin resin, styrene resin, styrene / acrylic resin, silicone resin, ester resin, fluorine-containing polymer resin, or the like 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.

  As a suitable fixing method used in the present invention, a so-called contact heating method can be exemplified. Typical examples of the contact heating method include a heat roll fixing method and a pressure contact heating fixing method in which fixing is performed by a rotating pressure member including a heating element fixedly arranged.

(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 in the past is exposed on the surface of the toner particles. 1) Low charge amount 2) Large difference in charge amount between high temperature and high humidity and low temperature and low humidity (environment dependence) 3) Types of colorants such as cyan, magenta, yellow and black pigments as in full color image recording For each color toner in the case of using toner, it is possible to wipe away variations in the charge amount. 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 Hereinafter, although an Example is given and this invention is demonstrated further in detail, this invention is not limited to these.

Example 1
[Production of toner particles]
<< Production of Toner Particles 1 >>
20 g of dye (1-19) was added to an aqueous solution in which sodium dodecyl sulfate was dissolved in 200 ml of pure water, and stirring and ultrasonic dispersion were performed to prepare a colorant dispersion in advance. Further, while heating low molecular weight polypropylene (number average molecular weight = 3200), a low molecular weight polypropylene emulsion dispersion emulsified in water so as to have a solid content concentration of 30% by mass with a surfactant was prepared. Next, 60 g of the low molecular weight polypropylene emulsified dispersion prepared above was mixed with the colorant dispersion, and 220 g of styrene monomer, 40 g of n-butyl acrylate monomer, 12 g of methacrylic acid monomer, and t-dodecyl mercaptan as a chain transfer agent. After adding 4 g and 2000 ml of degassed pure water, emulsion polymerization was performed by maintaining at 70 ° C. for 3 hours while stirring under a nitrogen stream.

  After adding sodium hydroxide to the obtained resin fine particle dispersion to adjust the pH to 7.0, 675 ml of a 2.7 mol% aqueous potassium chloride solution is added, and further 400 ml of isopropyl alcohol and polyoxyethylene octylphenyl ether are added. (Ethylene oxide average polymerization degree = 10) 22.5 g was dissolved in 168 ml of pure water and added, and the reaction was carried out while stirring at 6O 0 C for 6 hours. Then, it cooled to 30 degreeC on the conditions of 6 degreeC / min.

  Then, the particles are filtered off from the dispersion of the colored particles, and are redispersed in ion exchange water (pH = 3) in an amount 10 times by mass with respect to the whole particles. The process of separating the colored particles from the filter was repeated twice, followed by washing with only ion-exchanged water and drying with hot air at 40 ° C. to obtain colored particles. The colored particles thus obtained are referred to as “toner particles 1”.

<< Production of Toner Particles 2 >>
In the preparation of the toner particles 1, the dye (1-19) is changed to C.I. I. Colored particles were obtained in the same manner except that Pigment Blue 15: 3 (Dainippon Ink Co., Ltd.) was used. The colored particles thus obtained are referred to as “toner particles 2”.

<< Production of Toner Particles 2 >>
In the preparation of the toner particles 1, the dye (1-19) is changed to C.I. I. Colored particles were obtained in the same manner except that Solvent Blue 70 (Daiwa Kasei Co., Ltd.) was used. The colored particles thus obtained are referred to as “toner particles 3”.

<< Production of Toner Particles 4 >>
Colored particles were obtained in the same manner except that Dye (1-19) was replaced with D-1 and 15.0 g in Toner Preparation 1. The colored particles thus obtained are referred to as “toner particles 4”.

<< Preparation of thermoplastic resin (latex) >>
An interface in which 7.08 g of an anionic surfactant (sodium dodecylbenzenesulfonate: SDS) was previously dissolved in 2760 g of ion-exchanged water in a 5000 ml separable flask equipped with a stirrer, a temperature sensor, a condenser, and a nitrogen introducing device. The activator solution (aqueous medium) was charged, and the internal temperature was raised to 80 ° C. while stirring at a stirring speed of 230 rpm under a nitrogen stream.

  On the other hand, 72.0 g of a compound represented by the following formula (1) as a release agent is added to a monomer mixed solution composed of 115.1 g of styrene, 42.0 g of n-butyl acrylate, and 10.9 g of methacrylic acid, A monomer solution was prepared by heating to 80 ° C. and dissolving. The monomer solution (80 ° C.) is mixed and dispersed in the surfactant solution (80 ° C.) by a mechanical disperser having a circulation path to disperse emulsified particles (oil droplets) having a uniform dispersed particle size. A liquid was prepared. Next, an initiator solution prepared by dissolving 0.84 g of a polymerization initiator (potassium persulfate: KPS) in 200 g of ion-exchanged water is added to the dispersion, and the system is heated and stirred at 80 ° C. for 3 hours. Polymerization (first stage polymerization) was performed to prepare a latex.

  Next, an initiator solution prepared by dissolving 7.73 g of a polymerization initiator (KPS) in 240 ml of ion-exchanged water was added to this latex, and after 15 minutes, at 80 ° C., 383.6 g of styrene, 140. A monomer mixed solution consisting of 0 g, methacrylic acid 36.4 g, and t-dodecyl mercaptan 13.7 g was added dropwise over 126 minutes. After completion of the dropwise addition, polymerization (second stage polymerization) was performed by heating and stirring for 60 minutes, and then cooled to 40 ° C. to obtain a latex. This latex is referred to as “latex (1)”.

<< Preparation of Toner Particles 5 >>
(Adjustment of colorant dispersion)
16.0 g of dye D-2 and 200.0 g of ethyl acetate were placed in a separable flask, and the inside of the flask was replaced with nitrogen gas, followed by stirring to completely dissolve the dye. Subsequently, after dripping under stirring to 340.0 g of an aqueous solution containing 19.6 g of a surfactant EM-27C 27% solution (manufactured by Kao Corporation), an ultrasonic disperser UH-600 (manufactured by SMT Co.) was added. And emulsified for 300 seconds. Thereafter, ethyl acetate was removed under reduced pressure to obtain a dye solid dispersion. The average particle diameter of the colored particles in the obtained dispersion was 36 nm.

  1250 g of the latex (1) obtained by the preparation of the thermoplastic resin (latex), 2000 ml of ion-exchanged water, and a dispersion of the colored fine particles 5 obtained as described above were mixed with a temperature sensor, a cooling tube, nitrogen The mixture was stirred in a 5 L four-necked flask equipped with an introduction device and a stirring device. After adjusting the internal temperature to 30 ° C., 5M aqueous sodium hydroxide solution was added to this solution to adjust the pH to 10.0. Next, an aqueous solution in which 52.6 g of magnesium chloride hexahydrate was dissolved in 72 ml of ion-exchanged water was added over 10 minutes at 30 ° C. with stirring. After standing for 3 minutes, temperature increase was started, and the system was heated to 90 ° C. over 6 minutes (temperature increase rate = 10 ° C./min). In this state, the particle size of the associated particles was measured with “Coulter Counter TA-II”, and when the volume average particle size reached 6.5 μm, an aqueous solution in which 115 g of sodium chloride was dissolved in 700 ml of ion-exchanged water was added. Then, the particle growth was stopped, and the fusion was continued by heating and stirring at a liquid temperature of 90 ° C. ± 2 ° C. for 6 hours. Then, it cooled to 30 degreeC on the conditions of 6 degreeC / min. Then, the associated particles are filtered from the dispersion liquid of the associated particles, and after being redispersed in ion exchange water (pH = 3) in an amount 10 times the mass ratio of the entire associated particles, After the process of filtering the associated particles from the washing water was repeated twice, the washing treatment was performed only with ion-exchanged water and dried with hot air at 40 ° C. to obtain colored particles. The colored particles thus obtained are referred to as “toner particles 5”.

<< Production of Toner Particles 6-24 >>
Colored particles were obtained in the same manner as in the preparation of toner particles 5 except that Dye D-2: 15.0 g was changed as shown in Table 3. However, when adding general formula (3), equimolar is added with respect to general formula (1) or (2). The colored particles thus obtained are referred to as “toner particles 6 to 24”.

<< Preparation of Toner Particles 25 >>
In the preparation of the toner particles 5, dye D-2: 15.0 g was replaced with the comparative pigment (1-19), except that coloring particles were prepared in the same manner. It was seen. Furthermore, when removing ethyl acetate under reduced pressure, coarse crystals were precipitated, and a uniform dye solid dispersion could not be obtained. The average particle size was 360 nm or more and the distribution range was wide, and the transparency was so low that toner particles could not be formed.

<< Preparation of Colored Fine Particle Dispersion 26 >>
13.5 g of the polymer (P-1), 16.0 g of the dye (1-19), and 123.5 g of ethyl acetate were put into a separable flask, the inside of the flask was replaced with nitrogen gas, and the mixture was stirred and mixed. The dye was completely dissolved. Next, 238 g of an aqueous solution containing 8.0 g of Aqualon KH-05 (Daiichi Kogyo Seiyaku Co., Ltd.) was added dropwise and stirred, and then emulsified for 300 seconds using Clearmix W Motion CLM-0.8W (M Technique). did. Thereafter, ethyl acetate was removed under reduced pressure to obtain a core-type colored fine particle dispersion impregnated with the dye. The average particle diameter of the colored fine particles in the obtained colored fine particle dispersion was 135 nm. The average particle diameter is a volume average particle diameter measured using a Zetasizer manufactured by Malvern.

P-1: St / HEMA / SMA = 30/40/30
<< Preparation of Colored Fine Particle Dispersion 27 >>
To the core-type colored fine particle dispersion impregnated with the dye prepared with the colored fine particle dispersion 26, 0.5 g of potassium persulfate is further added, heated to 70 ° C. with a heater, and then 10.0 g of MMA ( The reaction was allowed to proceed for 5 hours while dropping methyl methacrylate) to obtain a core-shell type colored fine particle dispersion. The average particle diameter of the colored fine particles in the obtained colored fine particle dispersion was 146 nm. In addition, an average particle diameter is a volume average particle diameter measured using the Malvern company Zetasizer.

<< Preparation of Colored Fine Particle Dispersion 28 >>
13.5 g of polymer (P-1), 16.0 g of dye (D-2), 12.8 g of metal complex compound (MS-15), and 123.5 g of ethyl acetate were placed in a separable flask. After the inside was replaced with nitrogen gas, the dye was completely dissolved by stirring. Next, 238 g of an aqueous solution containing 8.0 g of Aqualon KH-05 (Daiichi Kogyo Seiyaku Co., Ltd.) was added dropwise and stirred, and then emulsified for 300 seconds using Clearmix W Motion CLM-0.8W (M Technique). did. Thereafter, ethyl acetate was removed under reduced pressure to obtain a core-type colored fine particle dispersion 1 impregnated with a dye. The average particle diameter of the colored fine particles in the obtained colored fine particle dispersion was 36 nm. The average particle diameter is a volume average particle diameter measured using a Zetasizer manufactured by Malvern.

<< Preparation of colored fine particle dispersion 29 >>
To the core-type colored fine particle dispersion impregnated with the dye prepared with the colored fine particle dispersion 28, 0.5 g of potassium persulfate is further added, heated to 70 ° C. with a heater, and then 10.0 g of MMA ( The reaction was allowed to proceed for 5 hours while dropping methyl methacrylate) to obtain a core-shell type colored fine particle dispersion. The average particle diameter of the colored fine particles in the obtained colored fine particle dispersion was 40 nm. In addition, an average particle diameter is a volume average particle diameter measured using the Malvern company Zetasizer.

<< Preparation of Colored Fine Particle Dispersion 30 >>
A core-shell colored fine particle dispersion was obtained in the same manner except that the amount of Aqualon KH-05 (Daiichi Kogyo Seiyaku Co., Ltd.) was changed to 1.0 g in the preparation of the colored fine particle dispersion 28. Table 4 shows the average particle size of the colored fine particles in the obtained colored fine particle dispersion.

<< Preparation of Colored Fine Particle Dispersions 31-39 >>
A core-shell type colored fine particle dispersion was obtained in the same manner except that the polymer (P-1), the dye and the metal complex compound were changed as shown in Table 4 in the preparation of the colored fine particle dispersion 29. Table 4 shows the average particle size of the colored fine particles in the obtained colored fine particle dispersion.

<< Production of Toner Particles 26 >>
1250 g of the latex (1) obtained by the preparation of the thermoplastic resin (latex), 2000 ml of ion-exchanged water, and the colored fine particle dispersion 26 obtained as described above were introduced into a temperature sensor, a cooling tube, and nitrogen introduced. The mixture was stirred in a 5 L four-necked flask equipped with a device and a stirring device. After adjusting the internal temperature to 30 ° C., 5M aqueous sodium hydroxide solution was added to this solution to adjust the pH to 10.0. Next, an aqueous solution in which 52.6 g of magnesium chloride hexahydrate was dissolved in 72 ml of ion-exchanged water was added over 10 minutes at 30 ° C. with stirring. After standing for 3 minutes, temperature increase was started, and the system was heated to 90 ° C. over 6 minutes (temperature increase rate = 10 ° C./min). In this state, the particle size of the associated particles was measured with “Coulter Counter TA-II”, and when the volume average particle size reached 6.5 μm, an aqueous solution in which 115 g of sodium chloride was dissolved in 700 ml of ion-exchanged water was added. Then, the particle growth was stopped, and the fusion was continued by heating and stirring at a liquid temperature of 90 ° C. ± 2 ° C. for 6 hours. Then, it cooled to 30 degreeC on the conditions of 6 degreeC / min. Then, the associated particles are filtered from the dispersion liquid of the associated particles, and after being redispersed in ion exchange water (pH = 3) in an amount 10 times the mass ratio of the entire associated particles, After the process of filtering the associated particles from the washing water was repeated twice, the washing treatment was performed only with ion-exchanged water and dried with hot air at 40 ° C. to obtain colored particles. The colored particles thus obtained are referred to as “toner particles 26”.

<< Preparation of Toner Particles 27-39 >>
In the production of the toner particles 26, colored particles were obtained in the same manner except that the colored fine particle dispersion 22 was replaced with the colored fine particle dispersions 27 to 39, respectively. The colored particles thus obtained are referred to as “toner particles 27 to 39”.

(Developer preparation)
To each of the toner particles 1 to 39 obtained as described above, hydrophobic silica (number average primary particle size = 12 nm, degree of hydrophobicity = 68) is added at a ratio of 1% by mass, and hydrophobicity is added. Titanium oxide (number average primary particle size = 20 nm, degree of hydrophobicity = 63) was added at a ratio of 1.2% by mass and mixed with a Henschel mixer to obtain a toner. These toners are referred to as “toner 1” to “toner 39” corresponding to the colored particles, respectively.

  Each of the toners obtained as described above and a ferrite carrier having a volume average particle diameter of 60 μm coated with a silicone resin were mixed to prepare a developer having a toner concentration of 6%. These developers are referred to as “developers 1 to 39” corresponding to the toners, respectively.

<< Y-toner preparation >> Polymerization toner by dispersing solid (pigment comparison)
In Toner Preparation 1, the dye (1-19) was changed to C.I. I. Colored particles were obtained in the same manner except that Solvent Yellow 79 (manufactured by Daiwa Kasei Co., Ltd.) was used. The colored particles thus obtained were subjected to the same operation as in the above [Development of developer] to prepare “Developer Y”.

[Development, evaluation]
For each of the developers 1 to 39 obtained as described above, a digital copying machine “Konica 7075” (manufactured by Konica Minolta Technologies, Inc.) in which the configuration of the fixing device is changed to the following configuration is used. By performing live-action tests on paper and OHP in a normal humidity environment (temperature 25 ° C, relative humidity 55%), (1) color reproducibility, (2) transparency, (3) chargeability, (4) resistance The offset property, (5) heat resistance, (6) light resistance, and (7) heat and humidity resistance were evaluated. Development conditions are as shown below.

(Development conditions)
Photoconductor surface potential: -700 V, DC bias: -500 V, Dsd (distance between photoconductor and developing sleeve): 600 μm, developer layer regulation: magnetic H-Cut system, developer layer thickness: 700 μm, developing sleeve diameter: 40 mm .

(Fixer)
As the fixing device, a heat roll fixing type was used. Specifically, a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer is formed on the surface of a cylindrical metal core (inner diameter = 40 mm, wall thickness = 1.0 mm, total width = 310 mm) made of an aluminum alloy having a heater in the center. A heating roller is formed by coating with a tube of (PFA) thickness 120 μm, 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 hardness) 48, 2 mm thick) to form a pressure roller, 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 linear velocity of printing was set to 480 mm / sec. Note that a web-type supply system impregnated with polydiphenyl silicone (having a viscosity of 10 Pa · s at 20 ° C.) was used as a cleaning mechanism of the fixing device. The fixing temperature was controlled by the surface temperature of the heating roller (set temperature 175 ° C.). The amount of silicone oil applied was 0.1 mg / A4.

(1) Color reproducibility (cyan / green)
The color reproducibility of the single-color image on the copy paper was evaluated according to the following evaluation criteria by visual evaluation using 10 monitors. The toner adhesion amount was evaluated in the range of 0.7 ± 0.05 (mg / cm ² ). The results are shown in Tables 5 and 6 below.

A: Excellent color reproducibility (bright cyan)
○: Excellent color reproducibility (cyan)
Δ: Although there is some color contamination, it is at a level where there is no practical problem (slightly turbid cyan color)
X: Color contamination is large and there is a problem in image quality (appears blue or cloudy blue).

  In addition, regarding the evaluation of color reproducibility, “Developer Y” prepared above was similarly developed on the sample, and a green sample as an intermediate color was also prepared, and was similarly evaluated by monitoring. The results are shown in Tables 5 and 6 below.

○: Excellent color reproducibility (brilliant green)
Δ: There is some color contamination, but it is at a level where there is no practical problem (slightly cloudy green)
×: Color contamination is large and there is a problem in image quality (a cloudy green and blackish impression is received).

(2) Transparency Concerning the transparency of the image, a transparent image (OHP image) is created, and the fixed image is referred to an OHP sheet on which toner is not supported by a “330 type automatic spectrophotometer” manufactured by Hitachi, Ltd. The visible spectral transmittance of the image was measured, the difference in spectral transmittance between 650 nm and 450 nm for yellow toner, the difference in spectral transmittance between 650 nm and 550 nm for magenta toner, and the spectral transmittance at 500 nm and 600 nm for cyan toner. And the transparency of the OHP image was ranked as follows. When this value is 70% or more, it can be determined that the film has good permeability. The toner adhesion amount was evaluated in the range of 0.7 ± 0.05 (mg / cm ² ).

A: 90% or more B: 80% to less than 90% B: 70% to less than 80% X: less than 70%

(3) Change in Charge Amount with Time Qa is the charge amount when the developer is set and the first image is output, and Qb is the charge amount when 1 million images are output, and the value of Qb / Qa Were evaluated according to the following evaluation criteria. The results are shown in Tables 5 and 6 below.

A: 0.9 or more and less than 1.1 ○: 0.8 or more and less than 0.9, or 1.1 or more and less than 1.2 Δ: 0.7 or more and less than 0.8, or 1.2 or more and less than 1.3 X: Less than 0.7 or 1.3 or more.

(4) Offset resistance With respect to offset resistance, after 10,000 sheets of A4 copy paper having a solid band-like image having a width of 5 mm in the vertical direction with respect to the transport direction are transported and fixed vertically, the perpendicular to the transport direction. A4 images having a halftone image with a width of 20 mm are transported continuously by 10,000 sheets in a horizontal feed, and then paused. After the machine was stopped overnight, the machine was started up again, and the presence or absence of image contamination due to the fixing offset phenomenon occurring on the first sheet was visually evaluated according to the following evaluation criteria. The results are shown in Tables 5 and 6 below.

◎: No stain on image ○: Very slight stain on image (no problem in practical use)
X: There is a stain on the image and it is not suitable for practical use.

(5) Heat resistance The fixing roller and the recovered silicone oil were observed, and coloring was visually evaluated according to the following evaluation criteria. The results are shown in Table 5 below.

○: The fixing roller and the silicone oil are not colored. ×: The fixing roller and the silicone oil are colored.

(6) Light resistance Regarding light resistance, after measuring the image density Ci immediately after recording, the image was irradiated with xenon light (70,000 lux) for 14 days using a weather meter (Atlas C.165), The image density Cf was measured again, and the dye residual ratio ({(Ci-Cf) / Ci} × 100%) was calculated from the difference in image density before and after the xenon light irradiation and evaluated. The image density was measured using a reflection densitometer (X-Rite 310TR). The evaluation results are shown in Tables 5 and 6 below.

A: Dye remaining ratio is 98% or more A: Dye remaining ratio is 95 to 98%
○: Dye remaining rate is less than 90 to 95% Δ: Dye remaining rate is less than 80 to less than 90% ×: Dye remaining rate is less than 80%.

(7) Heat and humidity resistance With respect to heat and humidity resistance, the image density Ci immediately after recording was measured and stored for 14 days under the condition of 50 to 80% RH, then the image density Cf was measured again, and the difference in image density before and after The dye residual ratio ({(Ci-Cf) / Ci} × 100%) was calculated and evaluated. The image density was measured using a reflection densitometer (X-Rite 310TR). In addition, the color change was observed visually. The evaluation results are shown in Tables 5 and 6 below.

A: Dye remaining ratio is 95% or more A: Dye remaining ratio is less than 90-95% B: Dye remaining ratio is less than 80-90% B: Dye remaining ratio is less than 80% X: The pigment residual ratio is less than 80%, and the color appears to be cloudy by visual observation.

  As is apparent from Table 5, the developers 4 to 24 using the dye of the present invention show better color reproducibility than the pigment system and the comparative dye system (developers 1 to 3). In particular, the dye having the structure represented by the general formula (2) showed a vivid hue in both cyan (monochrome) and green (intermediate). Further, it can be seen that the developers 11 to 24 to which the metal complex compound represented by the general formula (3) is added have improved light resistance and heat and humidity resistance and are excellent in storage stability. Compared with the comparative dye (1-19), the dye of the present invention was excellent in solubility and uniformly good in dispersion stability.

  As apparent from Table 6, in the developers 26 to 39 using the colored fine particle dispersion to which the resin is added, the developer 28 using the dye represented by the general formulas (1) and (2) of the present invention. No. to 39 show excellent color reproducibility not only for single colors but also for intermediate colors.

  Further, by using a system in which a resin is added to the developers 1 to 24 shown in Table 5, the developers 26 to 39 were able to further improve the chargeability. Further, by adding the metal complex compound represented by the general formula (3), light resistance and heat and humidity resistance can be improved, and an image that can be stored for a long period of time can be provided.

Claims (9)

An electrophotographic toner comprising a dye represented by the following general formula (1):

(In the formula, Q ₁ and Q ₂ each represents an atomic group necessary for forming a 5-membered or 6-membered nitrogen-containing heterocycle, and may be condensed or have a substituent. _{1 to} L ₁₀ each independently represents an unsubstituted or substituted methine group, R ₁ and R ₂ each represent a substituent, and m1, m2, n1, and n2 each represents 0 or 1) 2. The electrophotographic toner according to claim 1, wherein the dye represented by the general formula (1) is represented by the following general formula (2).

Wherein R _{11 to} R ₁₆ each independently represents a hydrogen atom or a substituent, and R ₁₃ and R ₁₄ or R ₁₅ and R ₁₆ may form a 5- or 6-membered ring, and L ₁₁ and L ₁₂ each independently represents an unsubstituted or substituted methine group, and Y ₁₁ and Y ₁₂ are each an oxygen atom, a sulfur atom, —CR ₁₇ R ₁₈ — or —NR _19- represents, and R ₁₇ , R ₁₈ and R ₁₉ each represents a hydrogen atom or a substituent.) 3. The toner for electrophotography according to claim 1, wherein the toner contains a metal complex compound represented by the following general formula (3).
General formula (3)
M (X1) _m (X2) _l · W1 _s
(In the formula, M represents a divalent ion of Ni, Co, Zn or Cu, X1 and X2 each independently represent a monodentate or bidentate ligand, and may be the same or different; And X2 may be linked, m and l each represent an integer of 0 to 2. W1 represents a counter ion when a counter ion is required to neutralize the charge, and s represents 0 or 1 To express.) The electrophotographic toner according to claim 3, wherein at least one of X1 and X2 in the general formula (3) is represented by the following general formula (4).

(In the formula, E ₁ represents a substituent, E ₂ represents an electron-withdrawing group having a Hammett substituent constant (σp) of 0.1 to 0.9, and R represents an alkyl group, an aryl group, or a heterocyclic group. Represents an alkoxy group, an aryloxy group or an amino group, and may have a substituent.   In addition to the dye represented by the general formula (1), the dye represented by the general formula (2), or the dye represented by the general formula (1) or the general formula (2), the general formula (3) The electrophotographic toner according to any one of claims 1 to 4, wherein colored fine particles containing a metal complex compound represented by formula (1) are dispersed in a thermoplastic resin. .   6. The toner for electrophotography according to claim 5, wherein the colored fine particles further contain a resin different from the thermoplastic resin.   7. The electrophotographic toner according to claim 5, wherein an average particle size of the colored fine particles is 10 nm or more and 100 nm or less.   An image forming method comprising at least a step of developing an electrostatic charge image formed on an electrostatic image bearing member with toner, and a step of transferring a toner image formed by development onto a transfer material. An image forming method comprising using the electrophotographic toner according to any one of items 1 to 7. A squarylium dye characterized by being a dye represented by the following general formula (5).

Wherein R _{11 to} R ₁₆ each independently represents a hydrogen atom or a substituent, and R ₁₃ and R ₁₄ or R ₁₅ and R ₁₆ may form a 5- or 6-membered ring, and R ₁₁ and R ₁₂ are each an alkyl group having a total carbon number of 18 or more, and L ₁₁ and L ₁₂ each independently represent an unsubstituted or substituted methine group. Y ₁₁ and Y ₁₂ each represent an oxygen atom, a sulfur atom, —CR ₁₇ R ₁₈ — or —NR ₁₉ —, and each of R ₁₇ , R ₁₈ and R ₁₉ represents a hydrogen atom or a substituent.