JPH0659518A - Composition for charge control agent and electrophotographic toner - Google Patents

Abstract

(57) [Abstract] [Purpose] A toner having a good charge buildup and not affected by temperature and humidity, and a charge control agent composition used therefor. [Composition] A quaternary ammonium salt having a polyacid anion or an organic sulfonate anion as an anion component, calcium carbonate, magnesium carbonate, barium carbonate, barium sulfate, copper sulfate, calcium sulfate, magnesium hydroxide, aluminum hydroxide, and silica. Calcium acid,
A charge control agent composition prepared from an inorganic pigment selected from aluminum silicate, zinc silicate, and dimagnesium phosphate, and a toner containing the composition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charge control agent composition useful for a toner which is an electrophotographic developer, and an electrophotographic toner containing the composition.

[0002]

2. Description of the Related Art In electrophotography, an electrostatic latent image is formed on a photoconductive layer made of a photoconductive material, developed with a powder developer, visualized, and then fixed with heat or a solvent. The method is generally used. The photoconductor layer can be positively or negatively charged, so that exposure under the original gives a positive or negative electrostatic latent image. Therefore, when the negative electrostatic latent image is developed with the positively charged developing powder, a positive-positive image corresponding to the original is produced.

As such an electrophotographic developer, a mixture of fine particle powder consisting of resin called toner and colorant and fine iron powder or ferrite powder called carrier is used.

In the powder toner, a binder resin which is an essential component is heated and melted, carbon as a colorant and a charge control agent are added thereto, dispersed by kneading, cooled, and then mechanically pulverized, After that, the method of classification is generally used.

The toner develops the latent image on the photosensitive member by a mechanism that causes electrification by friction with a carrier (two-component developer) and friction with a sleeve (one-component developer). Since the toner is consumed by the development, it is always replenished, but the replenished toner does not have an electric charge, so the toner is raised to a predetermined charge amount by stirring in the developing unit and friction on the sleeve. The charge amount of toner is often set to about 10 to 30 μC / g.

Controlling the chargeability of toner is the most important matter for toner. The charging characteristics of the toner are governed by the resin which is the main component thereof, but normally, the desired tribocharging characteristics are obtained by adding a charge control agent. Due to the recent demand for higher image quality, higher reliability, higher speed, etc., more precise charge control than in the past has become necessary. In particular, a charge control agent that has a faster charge rise and is stable against environmental changes and aging There is a strong demand.

In order to perform good development, how quickly the replenishment toner is started up to a predetermined charge amount is one of the characteristics required of the toner. If the toner has a poor start-up, low-charged toner is generated, it does not migrate to the photoconductor sufficiently, which causes a decrease in density. In addition, toner scattering occurs, background stains on the copy, copy Contamination inside the machine may occur or the developer may deteriorate faster.

In the case of a low speed copying machine, it can be covered to some extent by agitation in the developing section, but as the speed of the developing machine increases, the replenished toner is transferred from the developing section to the photoconductor more quickly, so that quick charging is performed. Is required to rise. Further, in the case of the one-component toner, the charging property must be generated only by the friction with the sleeve, not the friction with the carrier. Therefore, the rising property is more important than the two-component toner.

It has been proposed to use a quaternary ammonium salt as a charge control agent (Japanese Patent Laid-Open No. 62-53).
944, JP-A-62-71968, JP-A-62-3259). However, the proposed charge control agent has a compatibility relationship with the resin and does not easily mix uniformly with the resin during the production of the toner, leaving various problems in various characteristics of the toner.

In the case of a toner, it is very important that the charge control agent is uniformly dispersed in the resin. If the dispersibility is poor, the charge control agent is not uniformly mixed in the toner particles and the quality of the toner is deteriorated. Non-uniformity occurs, the rise of charging is lowered, and a change over time easily occurs. The toner using the proposed quaternary ammonium salt and the like still has a problem that the behavior such as unstable charge at high temperature and high humidity remains, and it is not yet satisfactory as a charge control agent for toner. .

Further, it is known that a sparingly water-soluble inorganic salt is internally added to the toner for the purpose of preventing fusion of the toner to the surface of the metal sleeve or the surface of the photosensitive member, improving durability, and stabilizing charging. For example, Japanese Patent Application Laid-Open No. 58-91462 discloses a toner containing barium sulfate internally, and Japanese Patent Application Laid-Open No. 1-230067 discloses a toner internally containing tin oxide.

However, the former toner is apt to cause aggregation of barium sulfate, and is not effective in improving various performances of the toner. There is a problem that scattering and image defects occur.

[0013]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, has a good charge rise, and is stable for a long time without being affected by changes in temperature and humidity even when repeated development by continuous use is performed. It is an object of the present invention to provide a charge control agent composition having good performance capable of reproducing the above image and a toner containing the composition internally added.

[0014]

As a result of various studies to solve these problems, the present inventors have prepared a charge control agent from a specific quaternary ammonium salt and a specific inorganic pigment, It has been found that the modified charge control agent composition has the characteristic that the dispersibility in a resin is very good, and the quaternary compound modified with the inorganic pigment thus prepared. The toner using the charge control agent composition comprising an ammonium salt has the above-mentioned problems, that is, problems such as accelerating the rise of charging, improving stability of charging performance, and preventing toner scattering and image defects. The present invention has been completed by finding out that it is a solution.

The present invention is a modified charge control agent composition prepared from a charge control agent comprising a quaternary ammonium salt having a polyacid anion or an organic sulfonate anion as an anion component and a specific inorganic pigment. Regarding

The present invention also relates to a fourth aspect having a polyacid anion or an organic sulfonate anion as an anion component.
The present invention relates to a toner, which is a developer for electrophotography, containing a modified charge control agent composition prepared from a charge control agent composed of a primary ammonium salt and a specific inorganic pigment.

The quaternary ammonium salt as a charge control agent that can be used in the charge control agent composition of the present invention is a quaternary ammonium salt having a polyacid anion or an organic sulfonate anion as an anion component. 4th that can be used
Representative examples of the quaternary ammonium salt include those represented by the following general formulas and oligomers or polymers having a quaternary ammonium salt. In each general formula, the anion X ⁻ represents a polyacid anion or an organic sulfonate anion.

[0018]

[Chemical 1]

(In the formula, R ₁ , R ₂ , R ₃ and R ₄ may be the same or different from each other, and each is a substituted or unsubstituted aromatic carbocyclic group or a substituted or unsubstituted aromatic heterocyclic group. Or a hydrocarbon group having a hydrogen atom or 1 to 22 carbon atoms, or a hydrocarbon group optionally containing an amide, ether, or thioether bond, X ⁻
Represents an anion. )

[0020]

[Chemical 2]

Wherein R ₁ and R ₂ are each independently hydrogen or a C ₁ -C ₂₂ hydrocarbon group, or
₁ and R ₂ may be connected to each other to form an aromatic ring. R ₃ is hydrogen or a C ₁ -C ₂₂ hydrocarbon group,
R ₄ and R ₅ each independently represent a C ₁ -C ₈ alkylene group which may contain an amide, ether or thioether bond in the group, and X ⁻ represents an anion. )

[0022]

[Chemical 3]

(In the formula, R ₁ and R ₂ may be the same or different from each other, and each is a substituted or unsubstituted aromatic carbocyclic group or a substituted or unsubstituted aromatic heterocyclic group, or
It represents a hydrogen atom or a hydrocarbon group having 1 to 22 carbon atoms, or a hydrocarbon group which may contain an amide, ether or thioether bond, and X ⁻ represents an anion. )

[0024]

[Chemical 4]

(In the formula, R ₁ , R ₂ and R ₃ may be the same or different from each other, and are each a substituted or unsubstituted aromatic carbocyclic group or a substituted or unsubstituted aromatic heterocyclic group, or Represents a hydrogen atom or a hydrocarbon group having 1 to 22 carbon atoms, or a hydrocarbon group which may contain an amide, ether or thioether bond, and Y represents C, O,
Represents S, and X ⁻ represents an anion. )

[0026]

[Chemical 5]

(In the formula, R ₁ , R ₂ and R ₃ may be the same or different from each other, and are each a substituted or unsubstituted aromatic carbocyclic group or a substituted or unsubstituted aromatic heterocyclic group or hydrogen. Represents an atom or a hydrocarbon group having 1 to 22 carbon atoms, or a hydrocarbon group which may contain an amide, ether or thioether bond, and X ⁻ represents an anion.)

[0028]

[Chemical 6]

(In the formula, R ₁ and R ₂ may be the same or different from each other, and each is a substituted or unsubstituted aromatic carbocyclic group or a substituted or unsubstituted aromatic heterocyclic group, or
It represents a hydrogen atom or a hydrocarbon group having 1 to 22 carbon atoms, or a hydrocarbon group which may contain an amide, ether or thioether bond, and X ⁻ represents an anion. )

[0030]

[Chemical 7]

(Wherein R ₁ is a substituted or unsubstituted aromatic carbocyclic group or a substituted or unsubstituted aromatic heterocyclic group, or a hydrogen atom or a hydrocarbon group having 1 to 22 carbon atoms, Or represents a hydrocarbon group optionally containing an amide, ether or thioether bond, and X ⁻ represents an anion.)

The anion component in the quaternary ammonium salt of the present invention is a polyacid anion or an organic sulfonate anion. As the polyacid anion, for example, either an isopolyacid anion having molybdenum or tungsten as a central atom and a heteropolyacid anion can be used.

As the organic sulfonate anion, any of organic sulfonate anions such as aliphatic sulfonate anion, aromatic sulfonate anion and araliphatic sulfonate anion can be used.

The inorganic pigments used in the present invention include barium sulfate, magnesium hydroxide, aluminum hydroxide, calcium carbonate, dimagnesium phosphate, magnesium carbonate, barium carbonate, barium chloride, calcium sulfate, copper sulfate, zinc silicate, They are calcium silicate and aluminum silicate.

As the above-mentioned inorganic pigment, either synthetic products or natural products can be used. It is also possible to use an inorganic pigment reaction liquid produced by the reaction. For example, a mixture of barium sulfate and aluminum hydroxide obtained by the reaction of barium chloride with aluminum sulfate and alkali, or a mixture of zinc carbonate and sodium sulfate obtained by the reaction of sodium carbonate and zinc sulfate, or sodium carbonate and calcium chloride. Calcium carbonate, obtained by reaction with
Alternatively, it is calcium sulfate or the like obtained by the reaction of sodium sulfate and calcium chloride.

The charge control agent composition of the present invention is prepared from the above-mentioned quaternary ammonium salt and an inorganic pigment. As a method for preparing a charge control agent composition from a quaternary ammonium salt and an inorganic pigment, any method can be adopted as long as a homogeneous composition of both can be obtained. In producing the quaternary ammonium salt, an inorganic pigment is added at any stage of the production process to obtain a homogeneous composition of the quaternary ammonium salt as a reaction product and the inorganic pigment as a final product. It is preferable.

It is particularly preferable that the inorganic pigment is added by being present together with the reaction raw material compound in the reaction system for producing the quaternary ammonium salt. Further, it may be added to the reaction mixture transferred from the quaternary ammonium salt formation reaction step to the purification step, or may be added by being mixed with the wet cake filtration product obtained from the purification step. The quaternary ammonium salt produced by the reaction may be filtered out in the purification step, dried, and then immediately added with an inorganic pigment, pulverized and mixed to prepare a homogeneous composition.

A charge control agent composition having the same performance by wet-mixing the dried quaternary ammonium salt and the inorganic pigment in a suitable solvent such as water, a mixture of water and an organic solvent, or an organic solvent alone. It is possible to get things.

The charge control agent composition obtained by the above method can be used as it is for the production of toner after drying. If necessary, it may be further pulverized and classified before use. The content of the inorganic pigment in the charge control agent composition obtained in the present invention is such that the charge control agent composition does not deteriorate the characteristics of the charge control agent.

The charge control agent composition of the present invention described above has a good dispersibility in a resin, and a toner using the charge control agent composition has a good start-up of charging, and has low temperature and low humidity and high temperature and high humidity. Under the environment, even if used for a long time, it is possible to solve the problem of toner charging instability and toner scattering,
As a result, a clear developed image can be obtained.

The toner of the present invention is characterized by containing the charge control agent composition of the present invention. In the general manufacturing method of powder toner, the temperature for heating and melting the resin is
Although it depends on the type of resin, it is generally 150 ° C or lower.
The charge control agent is dispersed therein by kneading. As the characteristics of the charge control agent, it is required that the melting point be higher than the kneading temperature and the solubility in the resin be extremely low. It is known that the charge control agent dispersed in the resin is dispersed in the form of small particles in individual toner particles obtained by pulverization and classification. Therefore, when manufacturing the charge control agent, it is important to design the charge control agent so as to maximize its characteristics.

The amount of the charge control agent composition was 0.
1 to 15% by weight, particularly preferably 0.5 to 10% by weight are suitable.

The toner of the present invention further contains a binding substance and a coloring material in addition to the charge control agent composition. Binders that can be preferably used in the toner of the present invention include polystyrene, monomers of styrene such as polyvinyltoluene and its substitution products, styrene-substituted styrene copolymers, styrene-acrylic acid ester-based copolymers, styrene- Methacrylic acid copolymer, styrene-acrylonitrile copolymer,
Examples thereof include polyvinyl chloride, polyethylene / silicone resin, polyester, polyurethane, polyamide, epoxy resin, modified rosin and phenol resin. However, other materials that have been used as the binder material for toner have been applicable.

As the coloring substance, for example, C.I. I. Pigment Yellow 12, C.I. I. Solvent yellow 1
8, C.I. I. Disperse Yellow 33, C.I. I. Pigment Red-122, C.I. I. Solvent Red-1
9, C.I. I. Pigment Blue 15, C.I. I. Pigment Black-1, C.I. I. Solvent Black-3,
C. I. Solvent black-22, carbon black, etc. can be mentioned. However, other materials that have been conventionally used as colorants for toner are also applicable.

In the toner powder of the present invention, in the present invention, the charge control agent composition is melt-blended in a range of 0.1 to 50% by weight with respect to the synthetic resin and solidified, and then hammer mill or other pulverizer. Coarsely pulverized with a jet mill pulverizer, then finely pulverized with a jet mill, and then classified by an air stream classifier, or a polymerization initiator is added to a synthetic resin monomer, and the charge control agent composition is added to the monomer. To the weight ratio of 0.1-50
%, And the mixture is polymerized while being suspended in water. At this time, other coloring agents such as dyes or carbon black may be added.

The toner produced in this manner gives a charge amount suitable for developing an electrostatic image by friction with a carrier, and is not affected by changes in temperature and humidity even after repeated development for a long time. The amount of charge is kept constant, the charge distribution is uniform, and it is also kept constant.

Examples of the carrier include iron powder, a magnetic core coated with a styrene-methylmethacrylate copolymer, a silicone resin, a mixed resin of a styrene-methylmethacrylate copolymer and a silicone resin, a carrier coated with a tetrafluorostyrene polymer, and the like. Can be used. Further, the charge control agent composition according to the present invention provides excellent charging characteristics even when used in a so-called one-component toner containing a magnetic material. It can also be used as a capsule toner and a polymerized toner.

The magnetic material used as the magnetic material includes fine metal powder of iron, nickel, cobalt, etc., iron,
Alloys of metals such as cobalt, copper, aluminum, nickel, zinc, metal oxides such as aluminum oxide, iron oxide, titanium oxide, ferrites such as iron, manganese, nickel, cobalt, zinc, vanadium nitride, nitride A nitride such as chromium, tungsten carbide, a carbide such as silicon carbide, and a mixture thereof can be used.

As the magnetic material, iron oxide such as magnetite, hematite and ferrite is preferable.

[0050]

EXAMPLES The present invention will be specifically described below with reference to production examples of the composition and use examples as toners, but the present invention is not limited to these examples. The amounts and parts of each component described in the examples are parts by weight unless otherwise specified.

Example 1 Quaternary ammonium salt:

[0052]

[Chemical 8]

13.0 parts of N, N-dimethyl-N, N-ditetradecyl ammonium chloride was added to 100 parts of methanol.
Dissolved in part. Aluminum hydroxide (2 μm) in it
Was added, and then an aqueous solution containing 10 parts of ammonium molybdate tetrahydrate and 60 parts of water was added. After stirring at 50 ° C., the white precipitate that had precipitated was filtered off and washed thoroughly with water. After drying, a composition 1 having a composition ratio of quaternary ammonium salt and aluminum hydroxide of 50:50 was obtained.

Next, 88 parts of styrene-n-butyl methacrylate copolymer resin [Haimer SBM-73F Sanyo Chemical Co., Ltd.], 5 parts of low molecular weight polypropylene [Viscor 550-P Sanyo Chemical Co., Ltd.], carbon Black [# 44 Mitsubishi Kasei Co., Ltd.] 5 parts, composition 1 2
Part pre-mixing, melt kneading, and further pulverization and classification to obtain a toner having a particle size of 5 to 25 μm.

To 3 parts of this toner, 97 parts of an iron powder carrier [TEFV 200/300, manufactured by Nippon Iron Powder Co., Ltd.] was mixed to prepare a developer. After this developer was stirred, the amount of tribo charge was measured with a blow-off charge measuring device (manufactured by Toshiba Chemical). After stirring for 30 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes, 30 minutes, and 2 hours, the tribo charge amount (μC / g) was 3.9, 5.5, 9.3, and 10.
The rise time was as short as 0, 100.4, 100.3, and 100.3, and the saturated charge amount was reached in 5 minutes, and the rise of charge was extremely good.

Further, when this toner was put in a developing device and continuous copying was carried out and an image test was carried out, a good image was obtained at the start, and the image quality did not change after 50,000 sheets, and toner scattering and offset were observed. Did not occur. Furthermore, high temperature and high humidity of 35 ° C, 85% RH and 10 ° C, 30
Even in a low temperature and low humidity environment of% RH, image quality equivalent to that in copying under a normal temperature and normal humidity environment was obtained. Further, neither toner scattering nor offset occurred.

Example 2 13.0 parts of N, N-dimethyl-N, N-ditetradecyl ammonium chloride was dissolved in 100 parts of methanol. Among them, ammonium molybdate tetrahydrate 10.0
An aqueous solution consisting of 1 part and 60 parts of water was added. After stirring at 50 ° C., the quaternary ammonium salt (Compound 1) was filtered off.

The wet cake was stirred and dispersed in 100 minutes of water at room temperature, 20 parts of the same aluminum hydroxide (2 μm) as in Example 1 was added, and the mixture was stirred overnight, filtered, and washed thoroughly with water. Then, it was dried to obtain a composition 2 in which the composition ratio of the quaternary ammonium salt (compound 1) and aluminum hydroxide was 50:50.

Next, a toner was prepared in the same manner as in Example 1 except that the composition 1 was replaced with the composition 2, and then the triboelectric charge amount of the toner was measured. As a result, the tribo charge amount (μC / g) at the stirring time with the iron powder carrier for 30 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes, 30 minutes and 2 hours was 3.6 and 4.9, respectively. , 9.0, 9.6, 9.8, 9.9, 10.2
Became. The triboelectric charge amount after stirring for 5 minutes was 94% of the value after 2 hours, and a toner having a good rising in a short time was obtained.

Further, when this toner was put in a developing device, continuous copying was carried out, and an image test was carried out.
A good image was obtained, the image quality did not change even after 50,000 sheets, and neither toner scattering nor offset occurred. Furthermore, good image quality was obtained without being affected by high temperature / high humidity and low temperature / low humidity environments.

Example 3 The quaternary ammonium salt (Compound 1) synthesized in the same manner as in Example 2 was filtered off and dried. After drying, the same aluminum hydroxide (2 μm) as in Example 1 was immediately added and mixed, and the mixture was ground with a grinder to obtain a composition 3 having a composition ratio of quaternary ammonium salt and aluminum hydroxide of 50:50.

Next, a toner was prepared in the same manner as in Example 1 except that the composition 1 was replaced with the composition 3, and then the tribo charge amount was measured. As a result, the stirring time with the iron powder carrier was 30 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes, 30 minutes.
Tribo charge amount (μC / g) for 2 minutes each
It became 3.4, 4.8, 8.8, 9.3, 9.5, 9.6, 10.3. The measured amount of stirring for 5 minutes is 90.3 compared to the value after 2 hours.
%, And a toner having a good start-up in a short time was obtained.

Further, when this toner was put in a developing device, continuous copying was carried out, and an image test was carried out.
A good image was obtained, the image quality did not change even after 50,000 sheets, and neither toner scattering nor offset occurred. Further high temperature and high humidity of 35 ° C, 85% RH and 10 ° C, 30% R
Even under the low temperature and low humidity environment of H, the image quality equivalent to that of copying under the normal temperature and normal humidity environment was obtained. Further, neither toner scattering nor offset occurred.

Comparative Example 1 A toner was prepared in the same manner as in Example 1 except that 1.0 part of the quaternary ammonium salt (Compound 1) synthesized and dried in the same manner as in Example 2 was used, except that aluminum hydroxide was not used. Then, the tribo charge amount was measured. Stirring time of developer is 30 seconds, 1
Tribo charge amount (μC / g) in minutes, 3 minutes, 5 minutes, 10 minutes, 30 minutes, 2 hours is 2.0, 2.8, 4.9, 6.
It became 5, 8.7, 9.2, and 10.0. The charge amount of tribo after stirring for 5 minutes was 65% of the charge amount of tribo after 2 hours, which was an extremely low charging rise.

Further, an image test was conducted in the same manner as in Example 1. As a result, a clear image without fog was obtained as the initial image, but from about 1,000 sheets, an unclear image with fog was obtained.

Comparative Example 2 A toner was obtained in the same manner as in Example 1 except that the quaternary ammonium salt (Compound 1) synthesized and dried in the same manner as in Example 2 was used, and the raw materials for producing the toner were as follows. .

Styrene-n-butyl methacrylate copolymer resin 88 parts [Haimer SBM-73F Sanyo Kasei Co., Ltd.] Low molecular weight polypropylene 5 parts [Viscor 550-P Sanyo Kasei Co., Ltd.] Carbon black [# 44 Mitsubishi Kasei Co., Ltd.] 5 parts Quaternary ammonium salt (compound 1) 1 part Aluminum hydroxide (2 μm) 1 part

Using this toner, a developer was prepared in the same manner as in Example 1, and the stirring time with the iron powder carrier was 30 seconds,
The amount of tribo charge for 1 minute, 3 minutes, 5 minutes, 10 minutes, 30 minutes, and 2 hours is 2.0, 3.0, 5.3, 7.0, respectively.
It became 9.0, 9.5 and 10.4. The tribo charge amount after stirring for 5 minutes was 67% of the value after 2 hours, and the charge rise was poor. Further, an image test was conducted in the same manner as in Example 1. As a result, the initial image was a clear image without fog, but from about 1,000 sheets, it was an unclear image with fog.

FIG. 1 compares the rising of the tribocharge amount with respect to the stirring time with the iron powder carrier for the toners of Examples 1 to 3 and Comparative Examples 1 and 2. As shown by these results, it is understood that the toner using the charge control agent composition of the present invention has an extremely excellent charging rise.

Further, since it is important that the toner and the carrier are uniformly dispersed in a short time for the property that the charging rises quickly, the toners of Examples 1 to 3 and Comparative Examples 1 and 2 are stirred for 30 seconds. The state of dispersion was visually observed and compared. Toner (3 parts) by toner (97 parts of iron powder carrier TEFV 200/300, manufactured by Nippon Iron Powder Co., Ltd.)
A developer was prepared with the composition of parts and an image was taken with a copying machine.

The toners of Examples 1 to 3 using the charge control agent composition of the present invention have a substantially uniform dispersion state of the toner and the carrier, whereas the toners of Comparative Examples 1 and 2 have a dispersion state. Was mottled and uneven. In the toners of Examples 1 to 3, the dispersion of the toner and the carrier was achieved in a short time, and as a result, as shown in FIG. Further, with the toners of Examples 1 to 3, good images were obtained with little background fog. It is considered that this is due to the charging property due to the difference in the dispersion state of the quaternary ammonium salt and the inorganic pigment.

Example 4 Similar to Example 1, except that aluminum hydroxide (2 μm
Composition 4 was prepared by replacing m) with aluminum hydroxide (30 μm). Further, a toner was prepared by using the composition 4 instead of the composition 1, and the triboelectric charge amount of the toner was measured. As a result, the mixing time of the toner and iron powder carrier is 3
The amount of tribo charge (μC / g) at 0 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes, 30 minutes, and 2 hours is 3.
It was 8, 5.6, 9.2, 9.9, 10.1, 100.2, 10.2. The value after stirring for 5 minutes is 97.0% of the value after 2 hours.
The charge rise was good.

When this toner was put in a developing device, continuous copying was carried out, and an image test was carried out, a good image was obtained at the start, and the image quality did not change even after 50,000 sheets, and there was no toner scattering or offset. There was no outbreak. 35 more
Even under high temperature and high humidity conditions of 85 ° C. and 85% RH and low temperature and low humidity conditions of 10 ° C. and 30% RH, image quality equivalent to copying under normal temperature and normal humidity environment was obtained. Further, neither toner scattering nor offset occurred.

Example 5 Quaternary ammonium salt:

[0075]

[Chemical 9]

10.6 parts of N, N-dimethyl-N, N-dihexadecyl ammonium chloride was added to 100 parts of methanol.
Dissolved in part. Separately, an inorganic pigment obtained by adding sodium carbonate to 16 parts of aluminum sulfate, 18.8 parts of barium chloride and 100 parts of water was added, and then an aqueous solution containing 9.2 parts of ammonium molybdate tetrahydrate and 60 parts of water was added. Added. After stirring for 2 hours at 50 ° C., the white precipitate that had precipitated was filtered off and washed thoroughly with water. It was dried to obtain a composition (5).

Next, a toner was prepared in the same manner as in Example 1 except that the composition 1 was replaced with the composition 5, and the triboelectric charge amount of the toner was measured. The stirring time with the iron powder carrier was 3
The amount of tribo charge in 0 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes, 30 minutes, and 2 hours is 3.0, 4.3, and 8.
It became 0, 8.8, 9.0, 9.3, 9.3. The measured value after stirring for 5 minutes was 94.6% as compared with the value after 2 hours, and a toner having a good start-up in a short time was obtained.

Further, when this toner was put in a developing device, continuous copying was carried out, and an image test was carried out.
A good image was obtained, the image quality did not change even after 50,000 sheets, and neither toner scattering nor offset occurred. Further high temperature and high humidity of 35 ° C, 85% RH and 10 ° C, 30% R
Even under the low temperature and low humidity environment of H, the image quality equivalent to that of copying under the normal temperature and normal humidity environment was obtained. Further, neither toner scattering nor offset occurred.

Example 6 Quaternary ammonium salt:

[0080]

[Chemical 10]

10.6 parts of N, N-dimethyl-N, N-dihexadecyl ammonium chloride was added to 100 parts of methanol.
Dissolved in part. 21.8 parts of sodium tungstate, 3.6 parts of sodium molybdate and 2.9 parts of sodium phosphate were added to 200 parts of water, and a lake agent prepared with 18 parts of hydrochloric acid was added. After stirring at 50 ° C for 2 hours, it is filtered and washed with water,
A cake of primary ammonium salt (compound 3) was obtained.

20 parts of the obtained quaternary ammonium salt (compound 3) cake (50% solid content) was added to 100 parts of a lower alcohol aqueous solution, and the mixture was stirred and dispersed overnight at room temperature, and then calcium carbonate (1.5 μm) was added. ) Was added, and the mixture was stirred and dispersed overnight, filtered, and the cake was thoroughly washed with water and dried to obtain a composition 6 containing a quaternary ammonium salt and calcium carbonate in a ratio of 1: 1. Next, a toner having the following composition was obtained in the same manner as in Example 1.

Styrene-n-butylmethacrylate copolymer resin 88 parts [Haimer SBM-73F Sanyo Kasei Co., Ltd.] Low molecular weight polypropylene 5 parts [Viscor 550-P Sanyo Kasei Co., Ltd.] Carbon black [# 44 Mitsubishi Kasei Co., Ltd.] 5 parts Composition 6 2 parts

Using this toner, a developer was prepared in the same manner as in Example 1, and the stirring time with the iron powder carrier was 30 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes, 30 minutes, 2 minutes.
Tribo charge amount in time is 5.0, 6.6, 10.3,
It was 11.0, 11.5, 11.6 and 11.6. The triboelectric charge amount after stirring for 5 minutes was 94.8% of the value after 2 hours, and the rise of charging was good.

Further, when this toner was put in a developing device, continuous copying was performed, and an image test was conducted, at the start,
A good image was obtained, the image quality did not change even after 50,000 sheets, and neither toner scattering nor offset occurred. Further high temperature and high humidity of 35 ° C, 85% RH and 10 ° C, 30% R
Even under the low temperature and low humidity environment of H, the image quality equivalent to that of copying under the normal temperature and normal humidity environment was obtained. Further, neither toner scattering nor offset occurred.

Comparative Example 3 After the cake of the quaternary ammonium salt (compound 3) obtained in Example 6 was dried, a toner having the following composition was obtained in the same manner as in Example 1. However, the same calcium carbonate as in Example 6 was used.

Styrene-n-butylmethacrylate copolymer resin 88 parts [Heimer SBM-73F Sanyo Chemical Co., Ltd.] Low molecular weight polypropylene 5 parts [Viscor 550-P Sanyo Chemical Co., Ltd.] Carbon black [# 44 Mitsubishi Kasei Co., Ltd.] 5 parts Quaternary ammonium salt (3) 1 part Calcium carbonate (1.5 μm) 1 part

Using the toner thus obtained, a developer was prepared in the same manner as in Example 1. 30 minutes stirring time with iron powder carrier
Seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes, 30 minutes,
Tribo charge amount in 2 hours is 3.5, 4.6, 7.2,
It was 7.8, 10.0, 10.5 and 11.5. The amount of tribo charge after stirring for 5 minutes was 67.8% of the value after 2 hours,
The toner had a poor charging rise. Further, this toner was put in a developing device, continuous copying was performed, and an image test was conducted. As a result, a clear image without fog was obtained as the initial image, but from about 1,000 sheets, it became an unclear image with fog.

Comparative Example 4 Composition 7 containing 10 parts of titanium oxide (anatus type 0.5 μm) in place of calcium carbonate in Example 6 and containing 1: 1 of quaternary ammonium salt (compound 3) and titanium oxide. Got Next, a toner having the following composition was obtained in the same manner as in Example 1.

Styrene-n-butylmethacrylate copolymer resin 88 parts [Haimer SBM-73F Sanyo Chemical Co., Ltd.] low molecular weight polypropylene 5 parts [Viscor 550-P Sanyo Chemical Co., Ltd.] carbon black [# 44 Mitsubishi Kasei Co., Ltd.] 5 parts Composition 7 2 parts

Using this toner, a developer was prepared in the same manner as in Example 1. Stirring time with iron powder carrier is 30 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes, 30 minutes, 2
The amount of tribo charge over time is 2.5, 3.5, 6.5, respectively.
It was 6.9, 9.3, 9.5, and 10.0. The tribocharge amount after stirring for 5 minutes was 69% of the value after 2 hours, and the toner had a poor charging rise. Further, this toner was put in a developing device, continuous copying was performed, and an image test was conducted. As a result, the initial image became an unclear image with fog.

Compositions 8 to 43 containing quaternary ammonium salts shown in Tables 1 to 7 were prepared in the same manner as in Example 1 and used in Examples 7 to 33, and Comparative Examples. Used in Comparative Examples 5 to 31 by the same method as in 2. The results are shown in Tables 8 to 14. In Tables 8 to 14, the resins used, the method of measuring the charge amount, and the criteria for judging each evaluation item are as follows.

Resin used A: Styrene-acrylic acid copolymer [Himmer SBM-
73 Sanyo Kasei Co., Ltd.] B: Styrene-acrylic acid copolymer [Haimer TB-1
000 Sanyo Chemical Co., Ltd.] C: Polyester [HP-313 Nippon Synthetic Chemical Industry Co., Ltd.
Made] D: Polyester [HP-320 Nippon Synthetic Chemical Industry Co., Ltd.
Made] E: polystyrene [average molecular weight 1500]

Charge amount: Measured value after stirring for 2 hours Judgment: ○: No problem in practical use ×: Problem in practical use

[0095]

[Table 1]

[0096]

[Table 2]

[0097]

[Table 3]

[0098]

[Table 4]

[0099]

[Table 5]

[0100]

[Table 6]

[0101]

[Table 7]

[0102]

[Table 8]

[0103]

[Table 9]

[0104]

[Table 10]

[0105]

[Table 11]

[0106]

[Table 12]

[0107]

[Table 13]

[0108]

[Table 14]

Example 34 6.24 parts of N, N, N-tri-n-butyl-N-benzylammonium chloride was dissolved in 100 parts of methanol. After adding 3.0 parts of calcium carbonate (1.5 μm), an aqueous solution consisting of 7.65 parts of sodium 1,7-dihydroxynaphthalene-3-sulfonate and 100 parts of water was added. After stirring at 50 ° C. for 2 hours, the white precipitate was filtered off, washed thoroughly with water, and dried to obtain a composition 44 in which the weight ratio of the quaternary ammonium salt to calcium carbonate was 75:25.

Composition 1 was added to composition 44 as in Example 1.
Instead of the above, toner was prepared and the triboelectric charge amount of the toner was measured. Stirring time of iron powder carrier and toner 30 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes, 30 minutes, 2
Tribo charge amount in time is 3.0, 4.2, 7.0, 9.0, 9.
It was 1, 9.2 and 9.3. The value after 5 minutes was 96.8% of the value after 2 hours, indicating a good rise of charging.

Further, when this toner was put in a developing device and continuous copying was carried out, and an image test was conducted, a good image was obtained at the start, and the image quality did not change even after 50,000 sheets, and toner scattering and offset were observed. Did not occur. Further high temperature and high humidity of 35 ° C, 85% RH and 10 ° C, 30% R
Even under the low temperature and low humidity environment of H, the image quality equivalent to that of copying under the normal temperature and normal humidity environment was obtained. Further, neither toner scattering nor offset occurred.

Example 35 Quaternary ammonium salt

[0113]

[Chemical 11]

6.24 parts of N, N, N-tri-n-butyl-N-benzylammonium chloride was added to 10 parts of methanol.
Dissolved in 0 parts. An aqueous solution containing 7.65 parts of sodium 1,7-dihydroxynaphthalene-3-sulfonate and 100 parts of water was added thereto. After stirring at 50 ° C. for 2 hours, the quaternary ammonium salt (compound 38) was filtered off, the wet cake was stirred and dispersed in 100 parts of water at room temperature, and then the same calcium carbonate (1. 5 μm)
After adding 3.0 parts and stirring overnight, it was filtered, washed thoroughly with water, and dried to obtain a composition 45 having the same composition ratio as the composition 44.

Composition 1 was added to composition 45 as in Example 1.
Instead of the above, toner was prepared and the triboelectric charge amount of the toner was measured. Stirring time of iron powder carrier and toner 30 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes, 30 minutes, 2
Tribo charge amount in time is 2.8, 4.0, 6.3, 8.7, 9.
It was 0, 9.1 and 9.2. The value after 5 minutes was 94.6% of the value after 2 hours, indicating a good rise in charging.

Further, when this toner was put in a developing device and continuously copied, and an image test was conducted, a good image was obtained at the start, and the image quality did not change even after 50,000 sheets, and toner scattering and offset were observed. Did not occur. Further high temperature and high humidity of 35 ° C, 85% RH and 10 ° C, 30% R
Even under the low temperature and low humidity environment of H, the image quality equivalent to that of copying under the normal temperature and normal humidity environment was obtained. Further, neither toner scattering nor offset occurred.

Example 36 The quaternary ammonium salt (compound 38) synthesized in the same manner as in Example 35 was filtered off, washed thoroughly with water and dried. Immediately after drying, the same calcium carbonate as in Example 34 (1.5 μm) was used.
m) was added and mixed, and the mixture was ground with a grinder to obtain a composition 46 in which the quaternary ammonium salt and calcium carbonate were 75:25.

Composition 1 was added to composition 46 as in Example 1.
Instead of the above, toner was prepared and the triboelectric charge amount of the toner was measured. Stirring time of iron powder carrier and toner 30 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes, 30 minutes, 2
Tribo charge amount in time is 2.6, 3.8, 6.0, 8.5, 8.
It was 8, 8.9 and 9.3. The value after 5 minutes was 91.4% of the value after 2 hours, indicating that the rise of charging was good.

Further, when this toner was put in a developing device and continuously copied, and an image test was conducted, a good image was obtained at the start, and the image quality did not change after 50,000 sheets, and toner scattering and offset were observed. Did not occur. Further high temperature and high humidity of 35 ° C, 85% RH and 10 ° C, 30% R
Even under the low temperature and low humidity environment of H, the image quality equivalent to that of copying under the normal temperature and normal humidity environment was obtained. Further, neither toner scattering nor offset occurred.

Comparative Example 32 The same procedure as in Example 1 was carried out using 1.0 part of the dried quaternary ammonium salt (Compound 38) synthesized in the same manner as in Example 35.
However, the toner was created without using aluminum hydroxide,
The triboelectric charge amount of the toner was measured. Stirring time of iron powder carrier and toner 30 seconds, 1 minute, 3 minutes, 5 minutes,
Tribo charge amount for 10 minutes and 2 hours is 2.0, 3.1, 5.
It was 2, 5.8, 7.0, 8.0 and 9.0. The value after 5 minutes is 2
It was 64.4% with respect to the value after the lapse of time, and the rise of charging was poor.

Further, an image test was conducted in the same manner as in Example 1. As a result, a clear image without fog was obtained as the initial image, but from about 1,000 sheets, an unclear image with fog was obtained.

Comparative Example 33 A toner was obtained in the same manner as in Example 1 with the following composition using the quaternary ammonium salt (Compound 38) synthesized and dried in the same manner as in Example 35.

Styrene-n-butyl methacrylate copolymer resin 88 parts [Haimer SBM-73F Sanyo Chemical Co., Ltd.] Low molecular weight polypropylene 5 parts [Viscor 550P Sanyo Chemical Co., Ltd.] Carbon black [# 44 Mitsubishi Kasei Co., Ltd.] 5 parts Quaternary ammonium salt (compound 38) 1 part Calcium carbonate (1.5 μm) 1 part

Using the toner thus prepared, the charge amount of the toner was measured in the same manner as in Example 1. The amount of tribo charge in the stirring time of the iron powder carrier and the toner for 30 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes, 2 hours was 2.1, 3.3, 5.3, 6.
It was 0, 7.7, 8.0 and 9.2. The value after 5 minutes was 65.2% with respect to the value after 2 hours, and the toner had a poor rise in charging. Further, an image test was conducted in the same manner as in Example 1. As a result, a clear image without fog was obtained as the initial image, but from about 1,000 sheets, an unclear image with fog was obtained.

FIG. 2 shows Examples 34 to 36 and Comparative Example 3.
For the toner of No. 3, the rise of the tribocharge amount with respect to the stirring time with the iron powder carrier was compared. As shown by these results, it is understood that the toner using the charge control agent composition of the present invention has an extremely excellent charging rise.

Example 37 A composition 47 was prepared in the same manner as in Example 34 except that 3 parts of aluminum hydroxide (2 μm) was used instead of calcium carbonate. Further, instead of the composition 1 as in Example 1,
A toner was prepared using the composition 47, and the triboelectric charge amount of the toner was measured. The amount of tribo charge in the mixing time of the toner and the iron carrier for 30 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes and 2 hours is 2.8, 4.1, 6.4 and 8.
It was 9, 9.0, 9.2 and 9.4. The value after 5 minutes was 94.7% of the value after 2 hours, indicating that the rise of charging was good.

When this toner was placed in a developing device and continuously copied, and an image test was carried out, a good image was obtained at the start, and the image quality did not change after 50,000 sheets, and toner scattering and offset occurred. Did not occur.

Example 38 As in Example 34, but instead of calcium carbonate,
Composition 4 using 3 parts of aluminum hydroxide (30 μm)
8 was prepared, and the composition 48 was used instead of the composition 1 in the same manner as in Example 1 to prepare a toner, and the triboelectric charge amount was measured. Mixing time of toner and iron powder carrier 30
Seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes, 30 minutes,
Tribo charge amount in 2 hours is 2.5, 3.9, 6.
It was 1, 8.7, 9.0, 9.1 and 9.4. The value after 5 minutes is 2
It was 92.6% of the value after the elapse of time, and the rise of charging was good.

When this toner was placed in a developing device and continuously copied, and an image test was performed, a good image was obtained at the start, and the image quality did not change even after 50,000 sheets, and toner scattering and offset were observed. Did not occur.

Comparative Example 34 As in Example 34, but instead of calcium carbonate,
A composition 49 was prepared using 3 parts of titanium oxide (Anatas type 0.5 μm), and the composition 49 was used in place of the composition 1 in the same manner as in Example 1 to prepare a toner, and tribocharged. The quantity was measured. Mixing time of toner and iron powder carrier for 30 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes, 30 minutes, 2 hours, tribo charge amount is 1.8, 3.0, respectively.
It was 4.8, 5.5, 6.0, 6.6 and 8.9. The value after 5 minutes was 61.8% with respect to the value after 2 hours, and the rise of charging was poor.

Further, an image test was conducted in the same manner as in Example 1. As a result, a clear image without fog was obtained as the initial image, but from about 1,000 sheets, an unclear image with fog was obtained.

Example 39 Quaternary ammonium salt:

[0133]

[Chemical 12]

N, N-dihexadecyl-N-methyl-N
12.12 parts of benzylammonium chloride were dissolved in 100 parts of methanol. Separately aluminum sulfate (16
After adding the inorganic pigment obtained by adding sodium carbonate to 12.72 parts of water salt), 14.84 parts of barium chloride (dihydrate) and 100 parts of water, sodium 1-naphthol-5-sulfonate 7. An aqueous solution consisting of 4 parts and 60 parts of water was added.
After stirring at 50 ° C. for 2 hours, the white precipitate thus deposited was filtered off, washed thoroughly with water, and dried to obtain a composition 50.

Next, a toner was prepared in the same manner as in Example 1 except that the composition 1 was replaced with the composition 50, and the triboelectric charge amount of the toner was measured. The stirring time of the toner and the iron powder carrier is 30 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes,
The amount of tribo charge for 30 minutes and 2 hours is 3.2,
It was 4.3, 6.2, 9.1, 9.2, 9.3, 9.3. The value after 5 minutes was 97.8% of the value after 2 hours, indicating a good rise of charging.

Further, when this toner was put in a developing device and continuous copying was carried out and an image test was carried out, a good image was obtained at the start, and the image quality did not change even after 50,000 sheets, and there was toner scattering and offset. Did not occur. Further high temperature and high humidity of 35 ° C, 85% RH and 10 ° C, 30% R
Even under the low temperature and low humidity environment of H, the image quality equivalent to that of copying under the normal temperature and normal humidity environment was obtained. Further, neither toner scattering nor offset occurred.

Example 40 6.24 parts of N, N, N-tri-n-butyl-N-benzylammonium chloride was dissolved in 100 parts of methanol. After adding 8 parts of precipitated barium sulfate (1.5 μm) and 8 parts of calcium carbonate (1.5 μm) thereto, sodium 1,7-dihydroxynaphthalene-3-sulfonate 7.65 was added.
An aqueous solution consisting of 1 part and 100 parts of water was added. 2 at 50 ° C
After stirring for a period of time, the white precipitate deposited was filtered off, washed thoroughly with water, and dried to obtain a composition 51 in which the composition ratio of the quaternary ammonium salt and the inorganic pigment was 40:60.

Next, a toner was prepared in the same manner as in Example 1 except that the composition 1 was replaced with the composition 51, and the triboelectric charge amount of the toner was measured. The stirring time of the toner and the iron powder carrier is 30 seconds, 1 minute, 3 minutes, 5 minutes, 10 minutes,
The amount of tribo charge for 30 minutes and 2 hours is 5.1,
It was 6.5, 10.2, 10.9, 11.4, 11.5, 11.5. The value after 5 minutes is 94.7% of the value after 2 hours,
The rise of charging was good.

When this toner was placed in a developing device and continuously copied, and an image test was conducted, a good image was obtained at the start, and the image quality did not change even after 50,000 sheets, and toner scattering and offset were observed. Did not occur. Further high temperature and high humidity of 35 ° C, 85% RH and 10 ° C, 30% R
Even under the low temperature and low humidity environment of H, the image quality equivalent to that of copying under the normal temperature and normal humidity environment was obtained. Further, neither toner scattering nor offset occurred.

Examples 41 to 54 and Comparative Example 35
-Comparative Example 48 In the same manner as in the method described in Example 34, the inorganic pigment was added during the production of the quaternary ammonium salt, and Tables 15 to 2 were used.
Composition 52-Composition 86 shown in Example 4 were prepared and Example 4
Used for 1 to Example 64. Further, a composition prepared in the same manner as in Example 35 and using a composition prepared in the same manner as in Comparative Example 33 using the dried quaternary ammonium salt was used in Comparative Example 3.
5 to Comparative Example 58 are shown. The results are shown in Tables 25-30.

In each table, the resin used, the method of measuring the charge amount, and the judgment criteria for each evaluation item are as follows.

Resin used in toner production A: Styrene-acrylic acid copolymer [Himmer SBM-
73 Sanyo Kasei Co., Ltd.] B: Styrene-acrylic acid copolymer [Haimer TB-1
000 Sanyo Chemical Co., Ltd.] C: Polyester [HP-313 Nippon Synthetic Chemical Industry Co., Ltd.
Made] D: Polyester [HP-320 Nippon Synthetic Chemical Industry Co., Ltd.
Made] E: polyester [average molecular weight 1500]

Charge amount: Measured value after stirring for 2 hours Judgment: ○ No practical problem × Practical problem

[0144]

[Table 15]

[0145]

[Table 16]

[0146]

[Table 17]

[0147]

[Table 18]

[0148]

[Table 19]

[0149]

[Table 20]

[0150]

[Table 21]

[0151]

[Table 22]

[0152]

[Table 23]

[0153]

[Table 24]

[0154]

[Table 25]

[0155]

[Table 26]

[0156]

[Table 27]

[0157]

[Table 28]

[0158]

[Table 29]

[0159]

[Table 30]

[0160]

From each of the examples and the comparative examples, when the charge control agent comprising the quaternary ammonium salt and the inorganic pigment is used, the quaternary ammonium salt having the effect of the charge control agent itself is extremely dispersed in the resin. It can be seen that each toner particle has a good charging property, that is, a good charging property, that is, a uniform charging level and an excellent charge retention property. Along with this, it becomes possible to disperse the toner particles and the carrier in a short time, the charge rises quickly, and the copy speed can be increased. At the same time, the toner has a longer life and is less susceptible to environmental changes such as low temperature and low humidity and high temperature and high humidity.

[Brief description of drawings]

FIG. 1 shows the rise of tribocharge amount with respect to the stirring time with a carrier in Examples 1 to 3 and Comparative Example 2.

FIG. 2 shows the rise of the tribocharge amount with respect to the stirring time with the carrier in Examples 34 to 36 and Comparative Example 33.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication G03G 9/08 368 (72) Inventor Shinichi Sato 3-7-6 Kamiyacho, Kita-ku, Tokyo Tsuchiya Chemical Industry Co., Ltd. Tokyo factory

Claims (2)

[Claims] 1. A quaternary ammonium salt having a polyacid anion or an organic sulfonate anion as an anion component, and barium sulfate, aluminum hydroxide, calcium carbonate, magnesium carbonate, barium carbonate, barium chloride, copper sulfate, zinc silicate. , Aluminum silicate, calcium sulfate, calcium silicate, dimagnesium phosphate,
A charge control agent composition prepared from one or more inorganic pigments selected from the group consisting of magnesium hydroxide. 2. A quaternary ammonium salt having a polyacid anion or an organic sulfonate anion as an anion component, and barium sulfate, aluminum hydroxide, calcium carbonate, magnesium carbonate, barium carbonate, barium chloride, copper sulfate, zinc silicate. , Aluminum silicate, calcium sulfate, calcium silicate, dimagnesium phosphate,
A charge control agent composition obtained by internally adding a charge control agent composition prepared from one or more kinds of inorganic pigments selected from the group consisting of magnesium hydroxide, a binder substance and a coloring substance as main components An electrophotographic toner containing.