JPH08160658A - Color toner for developing electrostatic charge image - Google Patents

Abstract

PURPOSE: To provide a color toner for developing an electrostatic image obtaining a clear color and excellent in heat resistance, light resistance, and OHP transparency. CONSTITUTION: This toner is obtained by directly suspension-polymerizing a composition containing at least a polymerization monomer, wax, and a colorant. The weight average diameter of the toner is set to 7μm or below, the wax is the ester wax containing one or more long-chain ester portions having the carbon number of 15 or above, and the colorant has the skeleton expressed by the formula. In the formula, X and/or Y indicates the aromatic group and its derivative such as the phenyl group and naphthyl group, or the heteroaromatic group and its derivative such as the pyridyl group, furyl group, and thiophenyl group.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic charge image developing color toner for developing an electrostatic charge image formed in an electrophotographic method, an electrostatic printing method or the like.

More specifically, it relates to a magenta toner obtained by aqueous suspension polymerization of a monomer composition containing at least a releasing agent and a colorant.

[0003]

2. Description of the Related Art Conventionally, a developer using an electrophotographic process has been prepared by adding a colorant, a charge control agent and a release agent to polyester, styrene-acryl, epoxy resin, etc., melt-kneading them, and uniformly dispersing them. A production method by a pulverization method is generally used in which the fine / coarse powder developer is pulverized to a predetermined particle size and excess excess / coarse powder developer is removed using a classifier.

However, with the recent improvement in image quality, it has become necessary to further reduce the particle size of the developer.

However, as the particle size measured by a Coulter counter becomes 7 μm or less, uniform dispersion of the raw materials used, high pulverizability with high efficiency, and classification of the developer into a sharp particle size distribution, which have not been a problem in the past, are performed. Tends to be extremely difficult.

In order to overcome the problems of the developer due to the crushing method, Japanese Patent Publication Nos. 36-10231 and 43-1.
No. 0799 and Japanese Patent Publication No. 51-14895, a method for producing a developer by a suspension polymerization method is proposed.
In the suspension polymerization method, a polymerizable monomer, a colorant, a polymerization initiator, and optionally a crosslinking agent, a charge control agent, and other additives are uniformly dissolved or dispersed to obtain a monomer composition. Then, this monomer composition is dispersed in a continuous phase containing a dispersion stabilizer, for example, an aqueous phase by using a suitable stirrer, and a polymerization reaction is simultaneously carried out to obtain a developer having a desired particle size. Is the way.

In this manufacturing method, it is not necessary to impart brittleness to the developer because it does not go through the crushing step, and a large amount of the low softening point substance which cannot be used in the conventional crushing method can be used. The selection range of materials such as In addition, it is difficult to expose the release agent or colorant, which is a hydrophobic material, to the surface of the developer particles.
It has attracted attention recently because of its characteristics such as less contamination of transfer rollers and fixing devices.

Further, in recent years, digital full-color copying machines and printers have been put into practical use, and toner image fidelity,
It has become necessary to further improve features such as releasability and color reproducibility.

As the required quality required for image fidelity,
Digital full-color copiers require a larger amount of developer to be transferred from the photoconductor to the transfer material than black-and-white copiers, and in order to support higher image quality in the future It is expected that there will be a demand for smaller particle sizes.

From this point of view also, the polymerization method, which can relatively easily produce a developer having a sharp particle size distribution and a fine particle size, has excellent characteristics.

Further, as the printers and copiers in the future are becoming faster and full-colored, improvement in low-temperature fixing property is also an important factor.

In a full-color copying machine, it is essential that the multicolor toners are sufficiently mixed in the fixing step to obtain color reproducibility and transparency of an OHP image.
Generally, a sharp melt low molecular weight resin is desired.

Generally, the black toner uses a crystalline material such as polyethylene wax or polypropylene wax having a relatively high releasability in order to improve the high temperature offset resistance at the time of fixing. When the above wax is used as the above, the transparency of the release agent is markedly impaired when output to the OHP due to the high crystallinity of the release agent.

Therefore, the high temperature offset resistance is eventually improved by uniformly applying silicone oil or the like to the heat fixing roller without adding a releasing agent as a color toner constituent component. However, since the excess silicone oil or the like adheres to the surface of the thus-obtained output transfer member, the user feels uncomfortable when using the output transfer member, which is not preferable.

Therefore, a developer for oilless fixing in which a large amount of a low softening point substance is contained in the developer has been studied, but it is excellent in low temperature fixing property and transparency, and at the same time high temperature offset resistance. No satisfactory developer has been obtained yet.

Further, since it becomes more difficult to uniformly encapsulate the release agent in the pulverization method as the toner has a fine particle diameter, encapsulation of the release agent in the fine particle size has become a major problem.

The required quality required for special colors such as color reproducibility is further improvement in color tone, saturation, coloring power, etc., and most of them are affected by the modification of the colorant itself.

Since magenta toner is particularly in great demand as a color to be used for skin color and the like, many pigments such as quinacridone type, thioindigo type, xanthene type, monoazo type, perylene type, diketopyrrolopyrrole type pigment have been conventionally used as toner pigments. Has been disclosed as.

For example, JP-B-49-46951 discloses 2,9-dimethylquinacridone pigment, JP-A-55-26574 discloses a thioindigo pigment, and JP-A-59-57256 discloses. Regarding xanthene dyes, JP-A-2-210459 discloses diketopyrrolopyrrole pigments, and JP-B-55-423.
No. 83 discloses anthraquinone dyes.

These colorants have good melt affinity to the binder resin and good light resistance even in polymerized toners, so that toners having excellent charging characteristics and color tone can be obtained. However, in order to obtain an image that is more faithful to the original while satisfying the low temperature fixing property and transparency, further image durability / environmental stability and
It is desired to improve the affinity with the release agent and the color tone and saturation.

Further, in recent years, as a further application of the electrophotographic technique, a movement for retransferring an image to a steel material, a cloth or the like has occurred, but such a processed product is conventionally used because it is easily used outdoors. The above heat resistance and light resistance are required.

From these viewpoints, the diketopyrrolopyrrole pigment has excellent heat resistance, but when it is used in a polymerized fine particle toner having a particle size of 7 μm or less, the surface of the toner is owing to its polar group characteristics. It has been difficult to obtain a product that is easily exposed to heat and has sufficient chargeability.

[0023]

SUMMARY OF THE INVENTION An object of the present invention is to provide a color toner for developing an electrostatic charge image, which solves the above-mentioned drawbacks.

That is, an object of the present invention is to provide a color toner for developing an electrostatic charge image, which has excellent OHP transparency and environmental stability and has charging characteristics.

Another object of the present invention is to provide a color toner for electrostatic image development which is excellent in heat resistance and light resistance.

A further object of the present invention is to provide a color toner for developing an electrostatic charge image, which can obtain extremely vivid colors.

[0027]

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner obtained by direct suspension polymerization of a composition containing at least a polymerizable monomer, a wax and a colorant. Is 7 μm or less, the wax is an ester wax having one or more long-chain ester moieties having 15 or more carbon atoms, and the colorant is a compound having a skeleton represented by the following structural formula. It is achieved by containing.

[0028]

Embedded image

[Wherein X and / or Y is an aromatic group represented by a phenyl group, a naphthyl group or the like and a derivative thereof, or a heteroaromatic group represented by a pyridyl group, a furyl group, a thiophenyl group or a derivative thereof] Indicates. ]

The present invention will be described in detail below.

As a result of intensive studies, the present inventors have found that the object of the present invention can be achieved by incorporating a diketopyrrolopyrrole pigment and a specific ester wax into the toner. This is because the ester group in the wax has an affinity for the functional group of the diketopyrrolopyrrole pigment,
It is considered that this occurs because the pigment is taken into the wax having hydrophobicity and embedded in the toner.

As X and Y in the general formula (I), an aromatic group represented by a phenyl group, a diphenyl group, a terphenyl group, a naphthyl group or a substituted derivative thereof, a pyridyl group, a pyrazinyl group, a triazinyl group and a furyl group. Group, pyrrolyl group, thiophenyl group, quinolinyl group, coumarinyl group, benzfuranyl group, benzimidazolyl group, oxazolyyl group, isoxazolyyl group, cinnolyl group, quinazolyl group, quinoxalyl group, phthalazinyl group, phthalazinedienyl group, phthalamidyl group Group, chromonyl group, naphtholactamyl group, quinononyl group, o-sulfobenzimidyl group, maleinimidyl group, naphthalidinyl group, benzimidazolonyl group, benzoxazolonyl group, benzthiazolonyl group, benzthiazo group Thionyl group, quinazolonyl group, quinoxalonyl group, lid Zonyl group, dioxapyrimidinyl group, pyridonyl group, isoquinonyl group, isoquinolinyl group, isothiazoliyl group, benzisoxazolyl group, benzisothiazolyl group, indazolonyl group, acridinyl group, acridonyl group, quinazolinedionyl group, quinoxalinedionyl group , A benzoxazine dionyl group, a benzoxadionyl group, a naphthalimidiyl group, and other hetero compounds and substituted derivatives thereof.

As an example of the substituent in the above-mentioned substituted derivative, it is necessary to select an appropriate one in view of the tint of the colorant and the like. In the present invention, a methyl group, an ethyl group, n
-Propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, n-octyl group, 1,1,3,3
Alkyl group such as 3-tetramethylbutyl group; methoxy group, ethoxy group, n-propoxy group, n-butoxy group,
Alkoxy groups such as t-butoxy group and n-hexyloxy group; alkoxyalkoxy groups such as methoxymethoxy group, ethoxyethoxy group, methoxyethoxy group, ethoxymethoxy group; methoxymethyl group, methoxyethyl group, ethoxyethyl group, n- Alkoxyalkyl groups such as propoxyethyl group, n-butoxyethyl group; aralkyl groups such as benzyl group, phenethyl group, γ-phenylpropyl group;
Alkoxycarbonyl groups such as methoxycarbonyl group, ethoxycarbonyl group, n-propoxycarbonyl group; alkylcarboxyl groups such as acetyloxy group, ethylcarboxy group, n-propylcarboxy group; hydroxyl group, hydrogen atom, fluorine atom, chlorine atom, bromine An atom etc. are mentioned.

As a method for synthesizing the compound represented by the general formula (I), for example, 1 mol of a succinic acid ester having a group such as an alkyl group, an allyl group or a cyclohexyl group,
Nitrile adducts of the general formulas X and Y (X = CN, Y = CN)
Is generally obtained by addition / condensation reaction, but the present invention is not limited thereto. In addition, for the purpose of changing the color and further improving the dispersibility,
A known method used for a conventionally known pigment, for example, the use of a dispersant represented by Sols Birds can be used for the colorant of the present invention.

The addition amount of these colorants used in the present invention is from 1 to 9% by weight, preferably 2 based on the toner, from the viewpoint of obtaining coloring power and preventing aggregation during dispersion.
~ 5% by weight.

These colorants are generally known colorants,
For example, C.I. I. Pigment Red 122, a quinacridone pigment, C.I. I. Pigment Red 57, azo pigments such as C.I. I. You may use together with the lake pigment of a rhodamine dye like Solvent Red 49.

In the present invention, the chargeability is improved by combining an ester wax having one or more long-chain ester moieties having 15 or more carbon atoms with the pigment of the present invention.

The wax of the present invention must have at least one long chain ester moiety having 15 or more carbon atoms.

When the number of carbon atoms is less than 15, the surface of the pigment is modified, but the water phase transfer property of the pigment cannot be suppressed, and the charge stability of the toner is deteriorated.

From this viewpoint, the carbon number of the long-chain ester portion in the present invention is more preferably 15 or more and 30 or less.

Further, in recent years, the need for full-color double-sided images has been increasing, and in forming a double-sided image, the toner image on the transfer paper formed first on the front surface is also formed on the rear surface. There is a possibility of passing through the heating portion of the fixing device again, and it is necessary to more fully consider the high temperature offset resistance of the toner. Therefore, in the present invention, addition of a large amount of ester wax is essential.

Therefore, the ester wax of the present invention is required to have releasability and transparency in addition to modification of the pigment, and it is preferable to add 5 to 30% by weight of the ester wax to the toner.

If it is added in an amount of less than 5% by weight, sufficient reformability is not exhibited, and further, the image on the back side tends to show an offset phenomenon at the time of fixing a double-sided image. On the other hand, if it exceeds 30% by weight, during the production of the toner, for example, in the production by the pulverization method, the device fusion or the toner fusion tends to occur,
Also in the production by the polymerization method, toner particles are likely to coalesce with each other at the time of granulation and the impact resistance against the drum is lowered, so that filming is likely to occur.

As a means for modifying the pigment of the present invention by adding an ester wax, known means such as master batching can be used in advance, but modification, dispersibility, re-aggregation, etc. In order to obtain the effect of the above, when both are added, 10 parts by weight of the ester wax is added to 100 parts by weight of the pigment.
It is desirable to add it in a ratio of 0 to 3000 parts by weight.

In the present invention, the ester wax used is preferably a compound having a main component maximum peak value measured according to ASTM D3418-8 of 40 to 90 ° C. When the maximum peak is less than 40 ° C., the self-aggregating force of the low softening point substance becomes weak, and as a result, the high temperature offset resistance becomes weak, which is not preferable for a full color toner. On the other hand, when the maximum peak exceeds 90 ° C., the fixing temperature becomes high, and it becomes difficult to appropriately smooth the surface of the fixed image, which is not preferable in terms of color mixing. Further, when the toner is obtained by the direct polymerization method, since the granulation / polymerization is carried out in an aqueous system, if the temperature of the maximum peak value is high, the low softening point substance mainly precipitates during granulation, which disturbs the suspension system. Not preferable.

In measuring the temperature of the maximum peak value of the present invention,
For example, Perkin Elmer DSC-7 is used. The melting point of indium and zinc is used to correct the temperature of the device detection unit, and the heat of fusion of indium is used to correct the amount of heat. An aluminum pan was used as a sample and an empty pan was set as a control, and the temperature rising rate was 10 ° C./min. Was measured.

Structural formulas of typical compounds of specific ester waxes preferable in the present invention are shown below as general structural formulas, general structural formulas, and general structural formulas.

[0048]

[Chemical 6]

(A, b: integers from 0 to 4, a + b
= 4 R ₁ , R ₂ : an organic group having an integer of 1 to 40 carbon atoms, and a carbon number difference between R ₁ and R ₂ is 3 or more m, n: an integer of 0 to 25, m And n cannot be 0 at the same time. )

[0050]

[Chemical 7]

(A, b: integers from 0 to 4, a + b
= 4, b ≠ 0 R ₁ : an organic group having an integer of 1 to 40 carbon atoms m, n: an integer of 0 to 25, and m and n are not 0 at the same time. )

[0052]

Embedded image

(A, b: integers from 0 to 3 and 1≤a
+ B ≦ 3 R ₁ , R ₂ : an organic group having an integer of 1 to 40 carbon atoms, and the difference in carbon number between R ₁ and R ₂ is 3 or more R ₃ : hydrogen atom, organic having 1 or more carbon atoms Basis. However, a
When + b = 2, one of R ₃ is an organic group having 1 or more carbon atoms, k: an integer from 1 to 3, m and n: an integer from 0 to 25, and m and n are 0 at the same time. It never happens. )

The ester wax preferably used in the present invention preferably has a hardness of 0.5 to 5.0.
The hardness of ester wax is 20mmφ in diameter and 5m in thickness.
It is a value obtained by measuring the Vickers hardness using a dynamic ultra-fine hardness meter (DUH-200) manufactured by Shimadzu Corporation after producing a cylindrical sample of m. Measurement condition is 0.5g
Of 10 μm under the condition of load speed of 9.67 mm / sec
After the displacement, it is held for 15 seconds, and the obtained dent shape is measured to determine the Vickers hardness. The hardness of the ester wax preferably used in the present invention has a value of 0.5 to 5.0. If the material has a hardness of less than 0.5 and has a low softening point, the pressure dependency and the process speed dependency of the fixing device become large, and the high temperature offset resistance effect is apt to be insufficiently expressed. Poor stability,
Since the self-aggregating force of the release agent itself is small, the modifying property of the pigment of the present invention tends to be insufficient.

The following compounds may be mentioned as specific compounds.

[0056]

[Chemical 9]

Further, in the present invention, it is preferable from the viewpoint of pigment modification that the ester wax is encapsulated in the outer shell resin layer by observing the toner cross-section layer using a transmission electron microscope (TEM).

As means for encapsulating the ester wax, a method of seed polymerization using suspension-polymerized particles as nuclei, as described in JP-A-59-6287, or JP-A-61-46.
Many methods such as a method of adding a polar resin having poor compatibility with an ester wax as disclosed in Japanese Patent No. 955 are disclosed, but what is the method that can be confirmed by the method of the present invention by these known methods? Any means may be used.

The present inventors have found that among these known methods, the method of adding a polar resin promotes uneven distribution of the ester wax, and even if combined with any known method, the effect is more exerted. In the present invention, the addition of polar substances is considered essential.

As the polar resin used in the present invention, commonly used materials such as a copolymer of styrene and (meth) acrylic acid, a maleic acid copolymer, a saturated polyester resin, an epoxy resin are preferably used. .

It is particularly preferable that the polar resin does not contain an unsaturated group capable of reacting with the monomer in the molecule. If it contains a polar resin having an unsaturated group, a crosslinking reaction with the monomer forming the outer shell resin layer will occur, resulting in an extremely high molecular weight for full-color toner, which is disadvantageous for color mixing of four-color toner. Absent.

As a specific method of measuring the tomographic plane of the toner in the present invention, the toner is sufficiently dispersed in a room temperature curable epoxy resin and then cured for 2 days in an atmosphere at a temperature of 40 ° C. After ruthenium tetraoxide and, if necessary, osmium tetraoxide are used together for dyeing, a flaky sample is cut out using a microtome equipped with diamond teeth and the toner morphology is measured using a transmission electron microscope (TEM). did. In the present invention, it is preferable to use the ruthenium tetroxide dyeing method in order to make a contrast between materials by utilizing a slight difference in crystallinity between the low softening point substance used and the resin constituting the outer shell. A typical example is shown in FIG. It was clearly observed that the low softening point substance was encapsulated by the outer shell resin.

Further, in the present invention, it is preferable that the shape factor SF1 measured by Luzex is 100 to 130 in order to secure transferability and developability during high speed copying.

SF1 representing the shape factor in the present invention means 100 toner images are randomly sampled using Hitachi FE-SEM (S-800), and the image information is the image made by Nicolet Co. through the interface. The value calculated from the following formula was defined as SF1 in the present invention by introducing it into an analyzer (Luzex3) for analysis.

[Definition formula of SF1]

[0066]

[Equation 1]

[In the formula, MXLNG represents the absolute maximum length of the developer on the image, and AREA represents the projected area of the developer. ]

A developer shape having a developer shape factor SF1 of more than 130 gradually approaches an irregular shape from a spherical shape, and at the same time, the transfer efficiency decreases, and a large amount of toner remains untransferred on the drum. As a result, filming is likely to occur during high-speed copying.

In the case of the toner of the present invention, the shape factor SF1 of the toner is 100 to 130, and more preferably 100 in order to secure practical filming resistance and transfer / developability.
A substantially spherical toner of 120 to 120 is preferable, and in order to faithfully develop finer latent image dots for higher image quality,
A toner having a particle diameter smaller than that of the developer, specifically, a weight average particle diameter measured by a Coulter counter of 7 μm or less, more preferably 4 μm to 7 μm and a number variation coefficient of 35% or less is preferable.

The polymerizable monomer used in the toner of the present invention includes styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene,
Styrene monomers such as p-ethylstyrene, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, acrylic acid 2
-Acrylic esters such as ethylhexyl, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n methacrylate -Amount of methacrylic acid ester such as octyl, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, etc. and other acrylonitrile, methacrylonitrile, acrylamide, etc. The body.

These monomers may be used alone or as a mixture. Among the above-mentioned monomers, it is preferable to use styrene or a styrene derivative alone or in combination with other monomers, from the viewpoint of developing characteristics and durability of the toner.

In order to control the molecular weight,
Known crosslinking agents and chain transfer agents may be added, and the preferable addition amount is 0.001 to 15% by weight.

Further, a resin may be added to the monomer system for polymerization. For example, a monomer is water-soluble and cannot be used because it dissolves in an aqueous suspension to cause emulsion polymerization, and thus cannot be used as an amino acid, a carboxylic acid group, a hydroxyl group, a sulfonic acid group, a glycidyl group, or a hydrophilic functional group-containing nitrile group. When it is desired to introduce monomer components into the toner, a random copolymer of these and a vinyl compound such as styrene or ethylene,
It can be used in the form of a copolymer such as a block copolymer or a graft copolymer, or in the form of a polycondensate such as polyester or polyamide, or a polyaddition polymer such as polyether or polyimine.

The amount used is preferably 1 to 20% by weight. The average molecular weight of the high molecular weight polymer containing these polar functional groups is preferably 5,000 or more.
When it is less than 5,000, particularly 4,000 or less, the present polymer is likely to concentrate near the surface, which is unfavorable since it tends to have a bad influence on the developability and blocking resistance. Also,
When a polymer having a molecular weight different from the molecular weight range of the toner obtained by polymerizing the monomer is dissolved in the monomer and polymerized, a toner having a wide molecular weight distribution and high offset resistance can be obtained.

As the polymerization initiator used in the polymerization method, any suitable polymerization initiator, for example, 2,
2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,
Azo-based or diazo-based polymerization initiators such as 1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile and azobisisobutyronitrile, benzoyl Examples thereof include peroxide type polymerization initiators such as peroxide, methyl ethyl ketone peroxide, diisopropyl peroxy carbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide and lauroyl peroxide. These polymerization initiators are 0.5 to 20 of the polymerizable monomer.
The addition amount of wt% is preferable, and they may be used alone or in combination.

In the polymerization method, known surfactants and organic / inorganic dispersants can be used as the dispersion stabilizer. Among them, the inorganic dispersant is unlikely to produce harmful ultrafine powder, and the dispersion stability is obtained due to its steric hindrance. Therefore, stability is not easily deteriorated even when the reaction temperature is changed, cleaning is easy, and the toner is not adversely affected. Therefore, it can be preferably used. Examples of such inorganic dispersants include polyvalent metal phosphates such as calcium phosphate, magnesium phosphate, aluminum phosphate and zinc phosphate, carbonates such as calcium carbonate and magnesium carbonate, and inorganic salts such as calcium metasilicate, calcium sulfate and barium sulfate. Examples thereof include inorganic oxides such as salts, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, silica, bentonite, and alumina.

These inorganic dispersants are composed of the polymerizable monomer 10
It is desirable to use 0.2 to 20 parts by weight per 0 parts by weight, but it is difficult to generate ultrafine particles, but it is somewhat difficult to atomize the toner, so 0.001 to 0.1 parts by weight Some surfactants may be used together.

Examples of the surfactant include sodium dodecylbenzenesulfate, sodium tetradecylsulfate, sodium pentadecylsulfate, sodium octylsulfate,
Examples thereof include sodium oleate, sodium laurate, sodium stearate, potassium stearate and the like.

When these inorganic dispersants are used, they may be used as they are, but in order to obtain finer particles, the inorganic dispersant particles can be generated in an aqueous medium. For example, in the case of calcium sulfate, a water-insoluble calcium phosphate can be produced by mixing an aqueous solution of sodium sulfate and an aqueous solution of calcium chloride under high-speed stirring, and more uniform and fine dispersion is possible.

In the present invention, it is desirable to add a charge control agent to the toner material in order to control the chargeability of the toner. Examples of these charge control agents include nigrosine dyes, triphenylmethane dyes, quaternary ammonium salts, quaternary ammonium salts, guanidine derivatives, imidazole derivatives, amine-based and polyamine-based compounds as positive charge control agents, and negative charge control agents. Examples include metal-containing salicylic acid compounds, metal-containing monoazo dye compounds, urea derivatives, styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, and the like. The addition amount of these charge control agents is preferably 0.1 to 10% by weight.

As an additive for imparting various toner characteristics, from the viewpoint of durability in the toner or when added to the toner, the particle diameter is 1/10 or less of the volume average diameter of the toner particles. Is preferred. What is the particle size of this additive?
It means the average particle size of the toner particles obtained by observing the surface thereof with an electron microscope. As the additives for imparting these characteristics, for example, the following ones are used.

1) Flowability-imparting agents: metal oxides (silicon oxide, aluminum oxide, titanium oxide, etc.), carbon black, fluorinated carbon, etc. Those subjected to a hydrophobic treatment are more preferable.

2) Abrasive: metal oxide (strontium titanate, cerium oxide, aluminum oxide, magnesium oxide, chromium oxide, etc.), nitride (silicon nitride, etc.), carbide (silicon carbide, etc.), metal salt (calcium sulfate, etc.) , Barium sulfate, calcium carbonate, etc.) etc.

3) Lubricants: Fluorine-based resin powder (vinylidene fluoride, polytetrafluoroethylene, etc.), fatty acid metal salt (zinc stearate, calcium stearate, etc.), etc.

4) Charge controllable particles: metal oxides (tin oxide, titanium oxide, zinc oxide, silicon oxide, aluminum oxide, etc.), carbon black, etc.

These additives are used in an amount of 0.1 to 10 parts by weight, preferably 100 parts by weight of the toner particles.
0.1-5 parts by weight are used. These additives may be used alone or in combination.

When a carrier is used as the developer, any conventionally known one can be used. For example, it is a magnetic substance such as iron, cobalt, or nickel, and an alloy or mixture thereof, or a surface of which is coated.

General production examples of color toners containing the colorant of the present invention will be given.

A release agent, a colorant, a charge control agent, a polymerization initiator, and other additives are added to the polymerizable monomer, and a homogenizer, an ultrasonic disperser, a ball mill, a sand mill, an attritor, or another media disperser. The monomer system uniformly dissolved or dispersed by the above method is dispersed in an aqueous phase containing a known dispersion stabilizer by a usual stirrer, homomixer, homogenizer or the like.

Granulation is preferably carried out by adjusting the stirring speed and time so that the monomer droplets have a desired toner particle size, generally 30 μm or less. After that, stirring is performed to the extent that the particle state is maintained and the particles are prevented from settling due to the action of the dispersion stabilizer.

The polymerization temperature is set to 40 ° C. or higher, generally 50 to 90 ° C. to carry out the polymerization. In addition, the temperature may be raised in the latter half of the polymerization reaction, and in the latter half of the reaction or the end of the reaction in order to remove unreacted polymerizable monomers and by-products that may cause odor during toner fixing. The aqueous medium may be partially distilled off later.

After the reaction is completed, the produced toner particles are collected by washing and filtering, and dried.

Depending on the case, classification is performed by a classifier, and further, silica or the like is dispersed in the classified product by a Henschel mixer or the like.

The particle size distribution measurement in the present invention will be described.

As a measuring device, a Coulter counter T
A-II type (manufactured by Coulter, Inc.)
Interface that outputs volume average distribution (made by Nikkaki)
And CX-1 personal computer (Canon)
Connected to the electrolyte using 1% sodium chloride using primary sodium chloride.
An aqueous Cl solution is prepared.

The measuring method is 100 to 1 of the electrolytic aqueous solution.
To 50 ml, 0.1 to 5 ml of a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant, and 0.5 to 50 mg of a measurement sample is further added.

The electrolytic solution in which the sample was suspended was subjected to dispersion treatment for about 1 to 3 minutes with an ultrasonic disperser, and the particle size distribution of particles of 2 to 40 μm was measured by the Coulter Counter TA-II type using a 100 μm aperture as an aperture. Is measured to obtain a volume average distribution and a number average distribution. The weight average particle diameter is obtained from the volume average distribution and the number average distribution thus obtained.

Regarding the light resistance, JIS K-7
102 (Method A, FV type). That is, the test image was irradiated with carbon arc lamp light under the condition that no water spray was applied, and its discoloration was measured by using a blue scale and evaluated.

The fixability, offset resistance, and
The evaluation method of the mixed color area and the transparency is as follows.

1) Fixability, Offset Resistance, and Color Mixing Region First, the toner containing the ester wax of the present invention is externally added with an appropriate amount of the above-mentioned external additive to obtain a developer. The unfixed image of the obtained developer is prepared by a commercially available copying machine.

When the toner is a black toner, the fixing property and the offset resistance are evaluated by a heat roller external fixing device having no oil application function.

Further, in the case of mono-color toner or full-color toner, in addition to a heat roller external fixing device having no oil application function, a commercially available full-color copying machine such as CLC is used.
Using a fixing device of -550 (manufactured by Canon Inc.), apply some oil uniformly to the fixing roller (for example, 0.02 g / A4).
Then, the fixability, offset resistance, and color mixture area are evaluated, and a fixed image for transparency evaluation is obtained.

At this time, as the roller material, a fluorine-based material is used for both the upper and lower parts. As for the fixing conditions, when the transfer material is SK paper (manufactured by Nippon Paper Industries Co., Ltd.), the nip is 7.0 mm and the process speed is 105 mm / s.
If the transfer material is an OHP sheet (Pictrico Trapen for copier / Asahi Glass Co., Ltd.), the nip is 6.0 m.
m, process speed 25 mm / sec, temperature control is performed every 5 ° C. within a temperature range of 80 ° C. to 230 ° C.

The fixing property is such that a fixed image (including a low-temperature offset image) is applied with a load of 50 g / cm ² on a sill-bon paper [Lenz Cleaning Paper “das”].
per (R) "(Ozu Paper Co. Lt
The temperature at which the density reduction rate before and after rubbing is less than 10% is determined as the fixing start point.

With respect to the offset resistance, the temperature at which the offset disappears visually is taken as the low-temperature offset starting point, and the temperature is raised.
The highest temperature without offset is the high temperature offset end point.

Further, as for the color mixture area, the image in the non-offset area is processed by the handy gloss meter gloss checker IG-310.
The gloss value is measured using (Horiba Seisakusho) and the gloss value is 7
The area is determined by defining it as the maximum value above.

2) Transparency The transmittance and the haze value (haze) for each toner amount per unit area of the obtained fixed image were measured to obtain an image density of 1.5.
The transparency was evaluated using the numerical value in. The method of measuring the transmittance and haze will be described below.

The transmittance was measured by Shimadzu's own spectrophotometer UV.
2200 (manufactured by Shimadzu Corporation) is used, and the transmittance of the OHP film alone is set to 100%. Magenta toner: 650 nm Cyan toner: 500 nm Yellow toner: 600 nm Transmittance at the maximum absorption wavelength To measure.

The haze measurement is carried out by the haze meter ND.
It measured using H-300A (made by Nippon Coloring Industry Co., Ltd.).

[0110]

The present invention will be described in detail with reference to examples.

Example 1 A 0.1 M Na ₃ PO ₄ aqueous solution and a 1 M CaCl ₂ aqueous solution are prepared. A 2-liter four-necked flask equipped with a high-speed stirring device TK-Homomixer was charged with ion-exchanged water 710.
Parts by weight and 450 parts by weight of a 0.1 mol-Na ₃ PO ₄ aqueous solution were added to adjust the rotation speed to 12,000, and the mixture was heated to 65 ° C. 68 parts by weight of a 1.0 mol-CaCl ₂ aqueous solution was gradually added to the mixture to form a fine water-insoluble dispersant Ca ₃ (P
A dispersion medium system containing O ₄ ) ₂ was prepared. On the other hand, the dispersoid system is styrene monomer 165 parts by weight n-butyl acrylate monomer 35 parts by weight

[0112]

[Chemical 10]

Saturated polyester 10 parts by weight (terephthalic acid-propylene oxide modified bisphenol A acid value 15, peak molecular weight 6000) Metal salicylate compound 2 parts by weight Compound (4) (maximum peak value 64.4 ° C.) 40 parts by weight

The above mixture was dispersed in an attritor for 3 hours, and then 10 parts by weight of 2,2'-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator was added to the dispersion medium. 1 while keeping the rotation speed
Granulated for 5 minutes. After that, the stirrer was changed from a high-speed stirrer to a propeller stirrer, the internal temperature was raised to 80 ° C., and the polymerization was continued at 50 rpm for 10 hours. After the polymerization was completed, the slurry was cooled and diluted hydrochloric acid was added to remove the dispersant.

By further washing and drying, the weight average diameter of the magenta toner measured by a Coulter counter is 6
The number variation coefficient is 28% at μm, and SF-1 is 105%.
Met. A schematic diagram of a tomographic photograph of the obtained magenta toner is shown in FIG. It shows a structure in which the compound (1) which is a low softening point substance is covered with an outer shell resin. 2% of hydrophobized titanium oxide was externally added to the obtained toner to obtain a toner having excellent fluidity.

To 7 parts by weight of this toner, 93 parts by weight of a ferrite carrier coated with an acrylic resin was mixed, and a full color copying machine CLC5 manufactured by Canon Inc. was used as a developer.
It was 23 ° C and 6
Under the condition of 0%, a stable clear and good magenta image was obtained without lowering the developability even after running 20,000 sheets.

The copy was also excellent in light resistance, was of the 7th grade, and was excellent in fixability and OHP transparency.

Further, a copying durability test was conducted under high temperature and high humidity of 30 ° C. and 80% for 10,000 sheets, but no fog or the like occurred.

Comparative Example 1 The same operation as in Example 1 was carried out except that the coloring agent in the formulation of Example 1 was changed to 3.5 parts by weight of a quinacridone pigment (CI Pig. Red 202). Weight average diameter 5.
An 8 μm toner was prepared and evaluated. Compared with Example 1, the saturation was inferior, an image with a dull color tone was obtained, and it did not reach a practical level.

Although the light resistance is the same as that of Grade 7,
It was inferior to Example 1 in the heat resistance test for 10 days at 100 ° C.

Comparative Example 2 The same procedure as in Example 1 was carried out except that 50 parts by weight of paraffin wax (maximum peak value: 73.1 ° C.) was used in place of the ester wax in the formulation of Example 1, and the weight average was obtained. A toner having a diameter of 6.6 μm was produced and evaluated. Example 1
Although there is no difference under the conditions of 23 ° C and 60% as compared with the above, the charging property cannot be obtained at 10,000 sheets durability under high temperature and high humidity of 30 ° C and 80%, and fog etc. will occur as the durability increases to a practical level. Did not reach.

The image was opaque with no OHP transparency.

Example 2 A coloring agent was added in the formulation of Example 1.

[0124]

[Chemical 11] The same operation as in Example 1 was carried out except that the above was changed to, and a toner having a weight average diameter of 5.3 μm was produced and evaluated. As a result, a stable, clear and good image free from scatter, fog, etc. was obtained even after the durability of 20,000 sheets as in Example 1 and the durability of 10,000 sheets under high temperature and high humidity.

The copy was also excellent in light resistance, was of the 7th grade, and was excellent in fixability and OHP transparency.

Example 3 A coloring agent was added in the formulation of Example 1.

[0127]

[Chemical 12] The same operation as in Example 1 was carried out except that the above was changed to, and a toner having a weight average diameter of 6.7 μm was produced and evaluated. As a result, a stable, clear and good image free from scattering, fog, and the like was obtained even after the durability of 20,000 sheets as in Example 1 and the durability of 10,000 sheets under high temperature and high humidity.

The light resistance of the copy was good, grade 6 to 7, and the fixing property and OHP transparency were excellent.

Example 4 In the formulation of Example 1, the amount of ester wax added was 7
The same operation as in Example 1 was carried out except that the parts by weight were used.
A toner having a weight average diameter of 5.1 μm was prepared and evaluated.

Then, compared with Example 1, it was 23 ° C., 6 ° C.
Although there is no difference under the condition of 0%, the electrification property gradually decreases at 10,000 sheets durability under high temperature and high humidity of 30 ° C and 80%,
Although it was at a practical level, it was observed that the image density tended to increase slightly with the endurance.

Example 5 In the formulation of Example 1, granulation time was changed from 15 minutes to 2 minutes.
Change to 5 minutes, and after 1 hour of polymerization, 0.1 mol-Na ₃ PO ₄
By adding 45 parts by weight of the aqueous solution and 6.8 parts by weight of the 0.1 mol-CaCl ₂ aqueous solution, the weight average diameter is
A toner having a number variation coefficient of 46% at 6.4 μm and SF-1 of 132 was obtained.

When the obtained toner was evaluated in the same manner as in Example 1, it was at a practical level with the durability of 20,000 sheets under the conditions of 23 ° C. and 60%, but there was a tendency for some fog to occur with the durability. It was observed.

[0133]

INDUSTRIAL APPLICABILITY The toner according to the present invention is superior in heat resistance and light resistance to other colorants, and also has bicyclo [3,3]
Since it has a unique molecular structure that is considered to be derived from the 3,1] dipyrrole ring structure, it is possible to obtain a toner having a higher coloring power and a higher coloring power than ever before.

Further, the colorant of the present invention is also excellent in alkali resistance, acid resistance, solvent resistance and the like, and is therefore particularly suitable for a so-called polymerization toner. In particular, in the suspension polymerization method of producing a toner by polymerizing in an aqueous medium, if the colorant has an affinity for water, the colorant is exposed on the toner surface, and a phenomenon such as fogging is likely to occur. However, in combination with the ester wax of the present invention, charging property, fixing property, O
A toner having excellent HP transparency can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic view of a tomographic plane of a toner of the present invention in which an ester wax is encapsulated in an outer shell resin.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification number Internal reference number for FI FI technical display location G03G 9/08 361 384 (72) Inventor Takao Ishiyama 3-30-2 Shimomaruko, Ota-ku, Tokyo Non non corporation

Claims (4)

[Claims] 1. A toner obtained by direct suspension polymerization of a composition containing at least a polymerizable monomer, a wax and a colorant, wherein the toner has a weight average diameter of 7 μm or less, and the wax has a carbon number. A color toner for developing an electrostatic charge image, which is an ester wax having one or more long-chain ester moieties of 15 or more and wherein the colorant has a skeleton represented by the following structural formula. Embedded image [In the formula, X and / or Y represent an aromatic group represented by a phenyl group, a naphthyl group or the like and a derivative thereof, or a heteroaromatic group represented by a pyridyl group, a furyl group, a thiophenyl group or a derivative thereof. ] 2. The wax and the colorant are contained in an amount of 5 to 30% by weight and 1 to 1% by weight of the resin component in the toner, respectively.
The color toner for developing an electrostatic image according to claim 1, wherein the color toner is contained in an amount of -9% by weight. 3. The color toner for developing an electrostatic charge image according to claim 1, wherein the ester wax contains a substance represented by the following general formula as a main component. Embedded image (A, b: an integer of 0 to 4 and a + b = 4 R ₁ , R ₂ : an organic group having an integer of 1 to 40 carbon atoms, and the difference in carbon number between R ₁ and R ₂ is 3 Above m and n are integers from 0 to 25, and m and n cannot be 0 at the same time.) (A, b: an integer from 0 to 4, a + b = 4, b ≠ 0 R ₁ : an organic group having an integer of 1 to 40 carbon atoms, m, n: an integer from 0 to 25, m and n cannot be 0 at the same time.) (A, b: integers from 0 to 3 and 1 ≦ a + b ≦ 3 R ₁ and R ₂ : organic groups having an integer from 1 to 40, and the difference in carbon number between R ₁ and R ₂ Is 3 or more R ₃ : a hydrogen atom, an organic group having 1 or more carbon atoms, provided that a
When + b = 2, one of R ₃ is an organic group having 1 or more carbon atoms, k: an integer from 1 to 3, m and n: an integer from 0 to 25, and m and n are 0 at the same time. It never happens. ) 4. A transmission electron microscope (TEM) of the toner.
4. The toner cross-sectional layer is observed by using, and the ester wax is encapsulated in an outer shell resin layer, and the shape factor SF1 measured by Luzex is 100 to 130. 4. A color toner for developing an electrostatic image as described above.