JP2007127919A - Charge control agent, its production method and toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a charge control agent having excellent charge control performance, its production method, and a toner having excellent charge buildup property, causing no scattering nor fogging even in image formation at high printing speed, and capable of providing a high quality image. <P>SOLUTION: The method for producing the charge control agent includes a process of synthesizing a specific azo-based metal complex by bringing an azo-based metal complex salt obtained by reacting a specific monoazo compound with a complexing agent into an ion exchange reaction with an ammonium counter-ion forming agent comprising urea and an inorganic ammonium salt. The charge control agent is obtained by the method for producing a charge control agent. The toner contains the charge control agent obtained by the method for producing a charge control agent. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a charge control agent, a method for producing the same, and a toner containing the charge control agent obtained by the method for producing the charge control agent.

  Conventionally, a charge control agent comprising an azo metal complex has been used in various fields. For example, in the field of toner constituting a developer used in electrophotography, it is used as a kind of toner constituent material. (For example, refer to Patent Document 1 or Patent Document 2). In particular, in recent years, the use of electrophotography has been expanded and applied to the field of light printing. As a result, it has been used as a constituent material of toner for use in the field of light printing. Yes.

  In the field of light printing, there is a demand for further increase in printing speed. In the field of printing including the field of light printing, not printing itself, but images formed by printing, that is, printed matter. Therefore, it is necessary to form an image formed in the field of so-called copying, that is, an image having a stable image quality over a longer period than that required for a copy.

However, in order to obtain stability in an image formed while increasing the printing speed, it is necessary to mix and charge newly replenished toner as a developer in a short time. As the speed of toner increases, the replenishment speed of the toner also increases, and the charge rising characteristics of the toner are insufficient. Due to the non-uniform charge amount, there is a problem that toner scattering and fogging occur due to toner that is not sufficiently charged.
In addition, when the developer is used for a long period of time, the chargeability of the toner as the developer changes depending on the use environment of the image forming apparatus, and the resulting image is particularly a solid image or a halftone image. If this is the case, there is a problem that density changes occur.

JP-A-7-97530 JP 2005-121776 A

The present invention has been made based on the background as described above. In the process of producing a charge control agent composed of an azo-based metal complex, the monoazo compound is converted into a metal complex. In the process of synthesizing an azo metal complex with a target ammonium ion as a counter ion by subjecting the azo metal complex salt obtained by the above to ion exchange reaction using ammonia water or an ammonia compound as an ammonium counter ion forming agent. Presence of azo-based metal complexes with ions other than ammonium ions as counter-products generated, and anionic properties consisting of counter ions of ammonium ions constituting various inorganic salts used as ammonium counterion forming agents The fact that ions are taken in as an impurity affects charge control performance. Results found that might have given, which has been completed, its purpose is to provide excellent charge control agent having a charge control performance, and its manufacturing method.
Another object of the present invention is to provide a toner having excellent charge rise characteristics and capable of obtaining a high-quality image without scattering or fogging even when an image is formed at a high printing speed. There is.

The method for producing a charge control agent of the present invention is a method for producing a charge control agent for obtaining a charge control agent comprising an azo-based metal complex,
An ion exchange reaction between an azo metal complex salt obtained by reacting a monoazo compound represented by the following general formula (1) and a complexing agent with an ammonium counter ion forming agent composed of urea and an inorganic ammonium salt is carried out as follows. It has the process of synthesize | combining the azo type metal complex represented by General formula (2).

[In formula, Ar < ¹ > and Ar < ² > show an aromatic group each independently. ]

[In formula, Ar < ¹ > and Ar < ² > show an aromatic group each independently. M represents a trivalent metal atom. ]

  In the method for producing a charge control agent of the present invention, it is preferable to use 3 to 20 equivalents of urea with respect to the azo metal complex salt.

  In the manufacturing method of the charge control agent of this invention, it is preferable to use 0.5-2 equivalent of inorganic ammonium salt with respect to an azo type metal complex salt.

  In the method for producing a charge control agent of the present invention, in General Formula (2) showing an azo-based metal complex, it is preferable that M is an iron atom.

  In the method for producing the charge control agent of the present invention, the azo metal complex represented by the general formula (2) in the reaction product obtained by ion-exchange reaction between the azo metal complex salt and the ammonium counter ion forming agent is used. A content rate can be 85 mass% or more.

  The charge control agent of the present invention is obtained by the above-described method for producing a charge control agent.

  The toner of the present invention contains a charge control agent obtained by the above-described method for producing a charge control agent.

  According to the present invention, in the process of an ion exchange reaction, it is possible to suppress the inclusion of impurities such as an azo metal complex and an ionic component having an ion other than an ammonium ion that adversely affects charge control performance as a counter ion. Therefore, it is possible to obtain a charge control agent that contains a specific azo-based metal complex having an ammonium ion as a counter ion in a high ratio, thereby obtaining excellent charge control performance, and a method for producing the same.

  According to the toner of the present invention, since the charge control agent having the above-described excellent charge control performance is contained, a high quality image can be obtained regardless of the use environment, and the image can be obtained at a high printing speed. Even in the case of forming a toner, it is possible to obtain a high-quality image without causing toner scattering and fogging caused by non-uniform charge amount of the toner because excellent charge rising characteristics are obtained. Can do.

Hereinafter, the present invention will be described in detail.
The charge control agent of the present invention is a charge control agent comprising an azo metal complex represented by the general formula (2) (hereinafter also referred to as “specific azo metal complex”), and the general formula (1). An azo metal complex salt (hereinafter also referred to as “specific intermediate”) obtained by reacting a monoazo compound (hereinafter also referred to as “raw material azo compound”) and a complexing agent, urea, and inorganic It is produced by a production method comprising a step of synthesizing a specific azo-based metal complex obtained by reacting with an ammonium counterion-forming agent containing an ammonium salt (hereinafter also referred to as “specific counterion-forming agent”). Is.

In the general formula (2) indicating the specific azo-based metal complex, Ar ¹ and Ar ² each independently represent an aromatic group, and Ar ¹ and Ar ² may be the same or different. Also good.

Examples of the aromatic group representing the groups Ar ¹ and Ar ² include an unsubstituted or substituted phenylene group and an unsubstituted or substituted naphthylene group.

  Moreover, in General formula (2), although M shows a trivalent metal atom, it is preferable that this M is an iron atom.

Preferable specific examples of the specific azo metal complex include an azo iron complex represented by the following general formula (3). In particular, in general formula (3), R ¹ , R ² and R ^{4 to} R ⁶ are A hydrogen atom and R ³ is a chlorine atom is preferable.

[Wherein, R ^{1 to} R ⁴ each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 18 carbon atoms, a linear or branched alkenyl group having 2 to 18 carbon atoms, unsubstituted or A sulfonamide group having a substituent, a mesyl group, a hydroxyl group, an alkoxyl group having 1 to 18 carbon atoms, an acetylamino group, a benzoylamino group, a halogen atom, a nitro group, an unsubstituted or substituted aryl group, and R ⁵ represents a hydrogen atom, a linear or branched alkyl group having 1 to 18 carbon atoms, a hydroxyl group, or an alkoxyl group having 1 to 18 carbon atoms, and R ⁶ represents a hydrogen atom or a linear chain having 1 to 18 carbon atoms. Or a branched alkyl group, a hydroxyl group, a carboxyl group, a halogen atom, or an alkoxyl group having 1 to 18 carbon atoms. ]

  Such a charge control agent comprising a specific azo metal complex is a process in which, for example, a raw material azo compound and a complexing agent are reacted in the presence of a specific counter ion forming agent, and the raw material azo compound and the complexing agent undergo a complex formation reaction ( Hereinafter, the specific intermediate obtained by the “complex formation reaction process”) and the specific counter ion forming agent are subjected to an ion exchange reaction (hereinafter also referred to as “ion exchange reaction process”). It can manufacture by the manufacturing method which has a complex formation process which synthesize | combines an azo type metal complex.

  The raw material azo compound used in the complex formation step is appropriately selected according to the specific azo metal complex to be synthesized. For example, in order to obtain the azo iron complex represented by the above general formula (3) as the specific azo metal complex An azo compound represented by the following general formula (4) can be used.

[Wherein, R ^{1 to} R ⁴ each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 18 carbon atoms, a linear or branched alkenyl group having 2 to 18 carbon atoms, unsubstituted or A sulfonamide group having a substituent, a mesyl group, a hydroxyl group, an alkoxyl group having 1 to 18 carbon atoms, an acetylamino group, a benzoylamino group, a halogen atom, a nitro group, an unsubstituted or substituted aryl group, and R ⁵ represents a hydrogen atom, a linear or branched alkyl group having 1 to 18 carbon atoms, a hydroxyl group, or an alkoxyl group having 1 to 18 carbon atoms, and R ⁶ represents a hydrogen atom or a linear chain having 1 to 18 carbon atoms. Or a branched alkyl group, a hydroxyl group, a carboxyl group, a halogen atom, or an alkoxyl group having 1 to 18 carbon atoms. ]

Examples of the complexing agent include sodium chromium salicylate, sodium cobalt salicylate, chromium acetate, cobalt acetate, ferric acetate, chromium sulfate, cobalt sulfate, ferric sulfate, chromium chloride, cobalt chloride, and ferric chloride. be able to.
The amount of the complexing agent to be used is preferably 1.0 to 1.6 mol, more preferably 1.05 to 1.30 mol, relative to 1 mol of the raw material azo compound.

  The specific counter ion forming agent contains urea and an inorganic ammonium salt, and examples of the inorganic ammonium salt constituting the specific counter ion forming agent include ammonium chloride and ammonium sulfate.

  The content ratio of urea in the specific counter ion forming agent constituting the specific counter ion forming agent, that is, the amount of urea used for the reaction is compared with the content ratio of inorganic ammonium salt, that is, the amount of the inorganic ammonium salt used for the reaction. Therefore, it is preferable to be excessive.

Specifically, the use amount of urea constituting the specific counter ion forming agent is preferably 3 to 20 equivalents, more preferably 5 to 15 equivalents, with respect to the specific intermediate produced by the complex formation reaction process. It is.
When the amount of urea used is excessive, it is possible to reduce the amount of inorganic ammonium salt to be used as the specific counter ion forming agent, thereby suppressing the inclusion of ionic components as impurities in the charge control agent obtained. Although it can be performed, the reaction rate of the ion exchange reaction is decreased, and foaming by the gas derived from carbonic acid generated by hydrolysis of urea becomes excessive, which is not preferable in terms of production. In addition, it is estimated that the reaction rate is lowered. However, when urea is used alone, there is a problem that the purity of the ammonium counter ion is lowered. On the other hand, when the amount of urea used is too small, the amount of inorganic ammonium salt to be used as the specific counter ion forming agent is increased, and a large amount of anionic ions as counter ions are taken in as impurities. The presence of charge tends to cause charge leakage, so that the obtained charge control agent may not have a desired charge control performance.
On the other hand, the amount of the inorganic ammonium salt constituting the specific counter ion forming agent is preferably 0.5 to 2 equivalents, more preferably 0.7 to the specific intermediate produced by the complex formation reaction process. -1.5 equivalents.
If the amount of inorganic ammonium salt used is excessive, the resulting charge control agent may not have the desired charge control performance. On the other hand, when the amount of the inorganic ammonium salt used is too small, the reaction rate of the ion exchange reaction is lowered, and the yield may be lowered.

  In the reaction system according to each of the complex formation reaction process and the ion exchange reaction process of the complex formation process, it is preferable to use a mixed solvent of water and an organic solvent as a solvent.

Examples of the organic solvent constituting the mixed solvent include hydrophilic organic solvents, amide solvents, ether solvents, ketone solvents, sulfoxide solvents, and aromatic solvents relating to unsubstituted or substituted aromatic compounds. It is done.
Here, as the hydrophilic organic solvent, alcohols or glycols are preferable, and specifically, for example, ethanol, n-propanol, isopropanol, n-butanol, amyl alcohol, benzyl alcohol, cyclohexanol, diacetone alcohol and the like. Monoalkyl ethers of glycols such as alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monoethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether and dipropylene glycol monoethyl ether, ethylene glycol monoacetate and propylene glycol mono Monohydric alcohols such as monoacetate of glycols such as acetate, e.g. Glycol, diethylene glycol, trimethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dihydric alcohols, such as glycols such as propylene glycol and butanediol.
As these hydrophilic organic solvents, alcohols having 1 to 8 carbon atoms or glycols having 2 to 18 carbon atoms are particularly preferable.

In the complex formation step, it is preferable that at least the reaction system in the ion exchange reaction process is alkaline, particularly alkaline having a pH of 8 or higher.
Moreover, as for the reaction conditions which concern on a complex formation process, reaction temperature is 60-100 degreeC, for example, and reaction time is 1 to 5 hours. The reaction temperature is preferably 65 to 80 ° C., and the reaction time is 2 to 4 hours.

  Here, in the complex formation step, the complex formation reaction process and the ion exchange reaction process can be continuously performed in the same reaction vessel, but each reaction step can be performed using a separate reaction vessel. In some cases, a wet cake may be obtained by filtering the reaction product in each reaction process, or a dried product obtained by drying the wet cake may be used in the next process or the next process.

  A charge control agent comprising a specific azo-based metal complex synthesized in the complex formation step is obtained through a post-treatment step such as washing treatment and drying treatment of the reaction product obtained in the complex formation step. It is done.

  According to the above method for producing a charge control agent, urea is used together with an inorganic ammonium salt as a specific counter ion forming agent in the ion exchange reaction process, and the amount of inorganic ammonium salt used is increased by using a large amount of this urea. Among the reaction products produced as by-products other than the specific azo metal complex in the ion exchange reaction, ions other than ammonium ions whose presence adversely affects the charge control performance, Specifically, as an azo metal complex having hydrogen ion or sodium ion as a counter ion (hereinafter, collectively referred to as “non-ammonium ion vs. metal complex”) or as a counter ion of ammonium ion constituting an inorganic ammonium salt. An ionic component consisting of anionic ions is taken up as an impurity It is possible to suppress the inclusion of a large amount of impurities that will be generated due to the supply of inorganic ammonium salt to the reaction system, and the like. Since a reaction product containing a high proportion of the azo metal complex can be obtained in the complex formation step, a charge control agent that can provide excellent charge control performance can be obtained.

  Here, the reason why the charge control performance of the charge control agent obtained by containing impurities such as non-ammonium ion-to-metal complex and ionic component is adversely affected is when non-ammonium ion-to-metal complex exists. Since the charging characteristics of each of these non-ammonium ion-to-metal complexes vary depending on the type of the non-ammonium ion-to-metal complex and also from the charging characteristics of the specific azo-based metal complex, such non-ammonium ion-to-metal complexes have a high ratio. The charge control agent contained is presumed to be due to an increase in the charge distribution. On the other hand, when an ionic component is present, charge leakage is likely to occur particularly in a high temperature and high humidity environment. It is assumed that the charge control agent cannot obtain high charge control performance.

  In addition, even when a large amount of urea is used as the specific counter ion forming agent, there is no adverse effect on the charge control performance of the resulting charge control agent. As a result, urea generates ammonium ions by hydrolysis. Along with this, carbonic acid is also produced, but this carbonic acid can be easily removed compared to ions produced due to the inorganic ammonium salt being used in the reaction, and the reaction production It is presumed that this is because it is difficult to become a constituent element of a complex by being taken into a product.

In this method for producing a charge control agent, as a reaction product in the complex formation step, an azo metal complex having a hydrogen ion as a counter ion and an azo system having a sodium ion as a counter ion together with a specific azo metal complex. Although a mixture in which a total of three types of metal complexes are contained is obtained, the content ratio of the specific azo metal complex in the reaction product can be 85% by mass or more.
Here, in the reaction product obtained in the complex formation step according to the method for producing the charge control agent of the present invention, the content ratio of the specific azo metal complex is preferably 85% by mass or more, particularly preferably 90%. It is at least mass%.

  The above-described effects are generally expressed by the general formula (2), in which the chargeability is smaller than that of a charge control agent composed of an azo chromium complex in which M is a chromium atom in the general formula (2). In the charge control agent comprising an azo-based iron complex in which M is an iron atom.

  The charge control agent of the present invention can be suitably used as a constituent material of toner constituting a developer used in electrophotography.

The toner of the present invention contains a charge control agent composed of the above-mentioned azo-based metal complex as an essential component, and as its constituent components, in addition to the charge control agent that is an essential component, for example, a resin and a colorant, if necessary In addition, additives such as a mold release agent and an external additive which are fixing improvers are contained.
Here, the components other than the charge control agent constituting the toner of the present invention are not particularly limited, and conventionally known components can be appropriately used.

Specifically, examples of the resin include thermoplastic resins such as a styrene acrylic resin, a polyester resin, and an epoxy resin, and these can be used alone or in combination of two or more.
Further, as the colorant, carbon black, magnetite, pigments and dyes can be used.
As the release agent, a crystalline substance having a low critical surface tension and a low melting point can be used. Specifically, low molecular weight polypropylene, low molecular weight polyethylene, Fischer-Tropsch wax, microcrystalline wax, paraffin wax, etc. And hydrocarbon waxes, long-chain carboxylic acid esters such as stearyl alcohol behenate, long-chain carboxylic acid esters such as pentaerythritol tetrabehenate, and natural waxes such as carnauba wax. The addition amount of the release agent is preferably 1 to 5% by mass, particularly preferably 2 to 10% by mass, based on the whole toner.

  The content ratio of the charge control agent in the toner of the present invention is preferably 0.1 to 5 parts by mass with respect to 100 parts by mass in total of the components of all toners other than the charge control agent constituting the toner. More preferably, it is 0.5 to 2 parts by mass.

  If the charge control agent content is too small, the toner may not be sufficiently charged. On the other hand, if the charge control agent content is excessive, the charge control agent has a charge control agent. Charge leakage occurs due to electrical conductivity, and sufficient chargeability of the toner cannot be obtained. At the same time, the constituent members of the image forming apparatus such as the developing sleeve are contaminated. In particular, the toner is used as a constituent material of the two-component developer. When used, the toner may not be sufficiently charged due to contamination of the carrier.

  The method for producing the toner of the present invention is not particularly limited, and conventionally known methods such as a melt kneading and pulverizing method and a polymerization method which are generally used as a method for producing the toner are appropriately used. Can be used.

The toner of the present invention as described above can be used as a magnetic or non-magnetic one-component developer, but can also be mixed with a carrier and used as a two-component developer.
When this toner is used as a magnetic one-component developer, magnetite can be suitably used as a colorant, and it is particularly preferable to use a toner having a number average primary particle size of 80 to 200 nm. Some magnetites have a cubic shape, a spherical shape, an octahedral shape, etc., but it is preferable to use a spherical shape when it is desired to add redness to the toner. In some cases, it is preferable to use a cubic crystal. The addition amount of the colorant in the toner constituting the magnetic one-component developer varies depending on the development method, but in the case of the non-contact development method, it is preferably 35 to 45% by mass with respect to the whole toner. If the amount is too small, toner scattering may occur. On the other hand, if the amount added is excessive, good developability may not be obtained.
Further, when used as a two-component developer, it is preferable to use carbon black as a colorant, and the addition amount is preferably 5 to 10% by mass with respect to the whole toner, and the color of the toner In order to control the taste, a color pigment can be used in combination.
When used as a two-component developer in this manner, as a carrier constituting the two-component developer, metals such as iron, ferrite, and magnetite, alloys of these metals with metals such as aluminum and lead, etc. Although conventionally known metal materials can be used, it is particularly preferable to use ferrite, and more preferably, light metal ferrite containing alkali metal or alkaline earth metal is used without containing copper or zinc. Further, as a carrier, it is preferable to use a carrier having a structure in which these metal materials are used as a core and the surface thereof is coated with a resin such as a silicone resin, a styrene acrylic resin, an acrylic resin, or a fluorine-containing resin. The volume-based median diameter is preferably 30 to 100 μm.

  According to the toner of the present invention as described above, the charge control agent having excellent charge control performance is contained. High-quality images can be obtained, and when an image is formed at a high printing speed, excellent charging is possible regardless of whether the toner is used as a constituent material of a one-component developer or a two-component developer. Since the rising characteristic is obtained, a high-quality image can be obtained without the occurrence of scattering and fogging caused by the uneven charge amount of the toner.

  Examples of the present invention will be described below, but the present invention is not limited thereto.

[Example 1]
(Production example of charge control agent)
First, 190 ml of pure water, 25 g of hydrochloric acid with a concentration of 37%, and 14.4 g (0.1 mol) of 2-amino-4-chlorophenol were added and stirred to dissolve the solid content. The solution was cooled to 3 ° C., and adjusted so that the temperature of the solution did not exceed 5 ° C., 60 ml (0.3 mol) of a sodium nitrite solution having a concentration of 36% was added dropwise. The diazo salt solution was obtained by making it react over 2 hours, adjusting so that it might become 3 degreeC.
Next, 165 ml of pure water, 30 g (0.15 mol) of a 20% sodium hydroxide solution, and 26.3 g (0.1 mol) of naphthol AS (3-hydroxy-2-naphthanilide) were charged and stirred. After dissolving the solid content, the resulting solution is cooled to 3 ° C., the whole amount of the prepared diazo salt solution is added, and it takes 5 hours until no diazo salt is present in the reaction system at a reaction temperature of 10 ° C. To obtain a coupling solution. To the obtained coupling solution, 100 ml of methyl alcohol, 30 g (0.15 mol) of sodium hydroxide solution with a concentration of 20%, 2.8 g (0.05 mol) of ammonium chloride (NH ₄ Cl), and 15 g of urea (0 Then, 40.6 g (0.05 mol) of an iron chloride (FeCl ₃ ) solution having a concentration of 20% is further added dropwise. After the addition is completed, the temperature of the solution is increased to 70 ° C. The reaction was allowed for 5 hours. After cooling the obtained reaction solution to 60 degreeC, 43g of reaction products were obtained by performing a filtration process, a washing process, and a drying process.
The amount of urea used as the specific counter ion forming agent in this complex formation step is 13 equivalents relative to the azo iron complex salt, while the amount of ammonium chloride used is 1.05 relative to the azo iron complex salt. Is equivalent.

The obtained reaction product was analyzed by NMR analysis to obtain an azo-based iron complex (hereinafter, referred to as “R ^1” , “R ^2”, and “R ^{4 to} R ^6” are hydrogen atoms and R ³ is a chlorine atom). "Ammonium ion-to-iron complex (A)"), an azo-based iron complex having a structure in which a hydrogen ion is used as a counter ion instead of an ammonium ion in the ammonium ion-to-iron complex (A), and an ammonium ion-to-iron The complex (A) was confirmed to be a mixture of a total of three types of complexes with an azo-based iron complex having a sodium ion as a counter ion instead of an ammonium ion, and NMR analysis and mass spectrometry (mass spectrum) ) Confirmed that the content of ammonium ion to iron complex (A) in the reaction product was 97% by mass. Hereinafter, this reaction product is referred to as “charge control agent (1)”.

[Example 2]
(Production example of charge control agent)
In Example 1, the reaction product was prepared in the same manner as in Example 1 except that the amount of ammonium chloride (NH ₄ Cl) used was changed from 2.8 g (0.05 mol) to 1.4 g (0.025 mol). Obtained.
The amount of urea used as the specific counter ion forming agent in this complex formation step is 13 equivalents relative to the azo iron complex salt, while the amount of ammonium chloride used is 0.52 relative to the azo iron complex salt. Is equivalent.

The obtained reaction product was analyzed by NMR analysis to obtain an ammonium ion-to-iron complex (A) in which R ¹ , R ² and R ^{4 to} R ⁶ are hydrogen atoms and R ³ is a chlorine atom in the general formula (3). ), An azo-type iron complex having a hydrogen ion as a counter ion instead of an ammonium ion in the ammonium ion-to-iron complex (A), and a sodium ion instead of an ammonium ion in the ammonium ion-to-iron complex (A). It was confirmed to be a mixture of a total of three types of complexes with an azo-based iron complex having a counter ion structure, and an ammonium ion-to-iron complex in the reaction product (by NMR analysis and mass spectrometry (mass spectrum)) ( It was confirmed that the content of A) was 96% by mass. Hereinafter, this reaction product is referred to as “charge control agent (2)”.

Example 3
(Production example of charge control agent)
In Example 1, the reaction product was prepared in the same manner as in Example 1 except that the amount of ammonium chloride (NH ₄ Cl) used was changed from 2.8 g (0.05 mol) to 3.5 g (0.065 mol). Obtained.
The amount of urea used as the specific counter ion forming agent in this complex formation step is 13 equivalents relative to the azo iron complex salt, while the amount of ammonium chloride used is 1.31 relative to the azo iron complex salt. Is equivalent.

The obtained reaction product was analyzed by NMR analysis to obtain an ammonium ion-to-iron complex (A) in which R ¹ , R ² and R ^{4 to} R ⁶ are hydrogen atoms and R ³ is a chlorine atom in the general formula (3). ), An azo-type iron complex having a hydrogen ion as a counter ion instead of an ammonium ion in the ammonium ion-to-iron complex (A), and a sodium ion instead of an ammonium ion in the ammonium ion-to-iron complex (A). It was confirmed to be a mixture of a total of three types of complexes with an azo-based iron complex having a counter ion structure, and an ammonium ion-to-iron complex in the reaction product (by NMR analysis and mass spectrometry (mass spectrum)) ( It was confirmed that the content of A) was 98% by mass. Hereinafter, this reaction product is referred to as “charge control agent (3)”.

Example 4
(Production example of charge control agent)
In Example 1, a reaction product was obtained in the same manner as in Example 1 except that the amount of urea used was changed from 15 g (0.32 mol) to 9.5 g (0.20 mol).
In this complex formation step, the amount of urea used as a specific counter ion forming agent is 8.3 equivalents relative to the azo iron complex salt, while the amount of ammonium chloride used is 0 with respect to the azo iron complex salt. .52 equivalents.

The obtained reaction product was analyzed by NMR analysis to obtain an ammonium ion-to-iron complex (A) in which R ¹ , R ² and R ^{4 to} R ⁶ are hydrogen atoms and R ³ is a chlorine atom in the general formula (3). ), An azo-type iron complex having a hydrogen ion as a counter ion instead of an ammonium ion in the ammonium ion-to-iron complex (A), and a sodium ion instead of an ammonium ion in the ammonium ion-to-iron complex (A). It was confirmed to be a mixture of a total of three types of complexes with an azo-based iron complex having a counter ion structure, and an ammonium ion-to-iron complex in the reaction product (by NMR analysis and mass spectrometry (mass spectrum)) ( It was confirmed that the content of A) was 91% by mass. Hereinafter, this reaction product is referred to as “charge control agent (4)”.

Example 5
(Production example of charge control agent)
In Example 1, the amount of ammonium chloride (NH ₄ Cl) used is 2.8 g (0.05 mol) to 3.5 g (0.065 mol), and the amount of urea used is 15 g (0.32 mol). A reaction product was obtained in the same manner as in Example 1 except that the amount was 9.5 g (0.20 mol).
In this complex formation step, the amount of urea used as the specific counter ion forming agent is 8.28 equivalents relative to the azo-type iron complex salt, while the amount of ammonium chloride used is 1 per azo-type iron complex salt. .31 equivalents.

The obtained reaction product was analyzed by NMR analysis to obtain an ammonium ion-to-iron complex (A) in which R ¹ , R ² and R ^{4 to} R ⁶ are hydrogen atoms and R ³ is a chlorine atom in the general formula (3). ), An azo-type iron complex having a hydrogen ion as a counter ion instead of an ammonium ion in the ammonium ion-to-iron complex (A), and a sodium ion instead of an ammonium ion in the ammonium ion-to-iron complex (A). It was confirmed to be a mixture of a total of three types of complexes with an azo-based iron complex having a counter ion structure, and an ammonium ion-to-iron complex in the reaction product (by NMR analysis and mass spectrometry (mass spectrum)) ( It was confirmed that the content of A) was 93% by mass. Hereinafter, this reaction product is referred to as “charge control agent (5)”.

Example 6
(Production example of charge control agent)
In Example 1, a reaction product was obtained in the same manner as in Example 1 except that 0.1 mol of 2-aminophenol was used instead of 0.1 mol of 2-amino-4-chlorophenol.
The amount of urea used as the specific counter ion forming agent in this complex formation step is 13 equivalents relative to the azo iron complex salt, while the amount of ammonium chloride used is 0.52 relative to the azo iron complex salt. Is equivalent.

The obtained reaction product is analyzed by NMR analysis, and the azo-based iron complex in which R ^{1 to} R ⁶ are hydrogen atoms in the general formula (3) (hereinafter also referred to as “ammonium ion versus iron complex (B)”). An azo-based iron complex having a hydrogen ion as a counter ion instead of an ammonium ion in the ammonium ion-iron complex (B), and a sodium ion instead of an ammonium ion in the ammonium ion-iron complex (B) It is confirmed that this is a mixture of a total of three types of complexes with an azo-based iron complex configured as an ion, and the ammonium ion versus iron complex (B) in the reaction product is confirmed by NMR analysis and mass spectrometry (mass spectrum). ) Content of 98% by mass was confirmed. Hereinafter, this reaction product is referred to as “charge control agent (6)”.

Example 7
(Production example of charge control agent)
In Example 1, the reaction product was prepared in the same manner as in Example 1 except that 0.1 mol of 2-amino-4,6-dinitrophenol was used instead of 0.1 mol of 2-amino-4-chlorophenol. Obtained.
The amount of urea used as the specific counter ion forming agent in this complex formation step is 13 equivalents relative to the azo iron complex salt, while the amount of ammonium chloride used is 0.52 relative to the azo iron complex salt. Is equivalent.

The obtained reaction product was analyzed by NMR analysis to obtain an azo-based iron complex (hereinafter referred to as “R”) in which R ² and R ^{4 to} R ⁶ are hydrogen atoms and R ¹ and R ³ are nitro groups in the general formula (3). "Ammonium ion-to-iron complex (C)"), an azo-based iron complex having a structure in which hydrogen ions are used instead of ammonium ions in the ammonium ion-to-iron complex (C), and ammonium ion-to-iron The complex (C) was confirmed to be a mixture of a total of three types of complexes with an azo-based iron complex having a sodium ion as a counter ion instead of an ammonium ion, and NMR analysis and mass spectrometry (mass spectrum) ) Confirmed that the content of ammonium ion to iron complex (C) in the reaction product was 98% by mass. Hereinafter, this reaction product is referred to as “charge control agent (7)”.

Example 8
(Production example of charge control agent)
In Example 1, a reaction product was obtained in the same manner as in Example 1 except that 0.1 mol of 2-amino-4-nitrophenol was used instead of 0.1 mol of 2-amino-4-chlorophenol. .
The amount of urea used as the specific counter ion forming agent in this complex formation step is 13 equivalents relative to the azo iron complex salt, while the amount of ammonium chloride used is 0.52 relative to the azo iron complex salt. Is equivalent.

The obtained reaction product was analyzed by NMR analysis to obtain an azo-based iron complex (hereinafter referred to as “R”, R ² and R ^{4 to} R ⁶ in the general formula (3) in which R ¹ , R ² and R ⁶ are hydrogen atoms and R ³ is a nitro group). "Ammonium ion-to-iron complex (D)"), an azo-based iron complex having a structure in which a hydrogen ion is used as a counter ion instead of an ammonium ion in the ammonium ion-to-iron complex (D), and ammonium ion-to-iron The complex (D) was confirmed to be a mixture of a total of three types of complexes with an azo-based iron complex having a sodium ion as a counter ion instead of an ammonium ion, and NMR analysis and mass spectrometry (mass spectrum) ) Confirmed that the content of ammonium ion to iron complex (D) in the reaction product was 98% by mass. Hereinafter, this reaction product is referred to as “charge control agent (8)”.

[Comparative Example 1]
(Production example of charge control agent)
In Example 1, the amount of ammonium chloride (NH ₄ Cl) used was changed from 2.8 g (0.05 mol) to 14 g (0.26 mol), and 2.5 g (0.147 mol) of ammonia was used instead of urea. A reaction product was obtained in the same manner as in Example 1 except that.
In this complex formation step, the amount of ammonia used as the specific counter ion forming agent is 2.95 equivalents relative to the azo-type iron complex salt, while the amount of ammonium chloride used is 5% relative to the azo-type iron complex salt. .25 equivalents.

The obtained reaction product was analyzed by NMR analysis to obtain an ammonium ion-to-iron complex (A) in which R ¹ , R ² and R ^{4 to} R ⁶ are hydrogen atoms and R ³ is a chlorine atom in the general formula (3). ), An azo-type iron complex having a hydrogen ion as a counter ion instead of an ammonium ion in the ammonium ion-to-iron complex (A), and a sodium ion instead of an ammonium ion in the ammonium ion-to-iron complex (A). It was confirmed to be a mixture of a total of three types of complexes with an azo-based iron complex having a counter ion structure, and an ammonium ion-to-iron complex in the reaction product (by NMR analysis and mass spectrometry (mass spectrum)) ( It was confirmed that the content of A) was 76% by mass. Hereinafter, this reaction product is referred to as “comparison charge control agent (1)”.

[Comparative Example 2]
(Production example of charge control agent)
A reaction product was obtained in the same manner as in Example 1, except that 5 g (0.254 mol) of ammonia was used instead of ammonium chloride (NH ₄ Cl) and urea.
In addition, the usage-amount of ammonia as a specific counter ion formation agent in this complex formation process is 5.9 equivalent with respect to an azo type iron complex salt.

The obtained reaction product was analyzed by NMR analysis to obtain an ammonium ion-to-iron complex (A) in which R ¹ , R ² and R ^{4 to} R ⁶ are hydrogen atoms and R ³ is a chlorine atom in the general formula (3). ), An azo-type iron complex having a hydrogen ion as a counter ion instead of an ammonium ion in the ammonium ion-to-iron complex (A), and a sodium ion instead of an ammonium ion in the ammonium ion-to-iron complex (A). It was confirmed to be a mixture of a total of three types of complexes with an azo-based iron complex having a counter ion structure, and an ammonium ion-to-iron complex in the reaction product (by NMR analysis and mass spectrometry (mass spectrum)) ( It was confirmed that the content of A) was 65% by mass. Hereinafter, this reaction product is referred to as “comparison charge control agent (2)”.

  Using the charge control agents obtained in each of Examples 1 to 8 and Comparative Examples 1 to 2, a toner is produced by the following method, and a two-component developer is produced using the obtained toner. did.

First, 1 part by mass of the charge control agent, 100 parts by mass of styrene acrylic resin (styrene: butyl acrylate: methyl methacrylate = 70: 20: 5 (mass ratio), softening point 128 ° C.), carbon black “Mogal L” (Cabot) 8 parts by mass) and 6 parts by mass of low molecular weight polypropylene “660P” (manufactured by Sanyo Kasei Kogyo Co., Ltd.) were mixed with a Henschel mixer, and the resulting mixture was melt-kneaded using a twin screw extruder and cooled. After that, the mixture was pulverized using a jet mill and classified using a cyclone classifier to obtain colored particles having a volume-based median diameter of 8.5 μm.
Next, 0.8 parts by mass of hydrophobic silica having a number average primary particle size of 12 nm and a hydrophobization degree of 67 is added to 100 parts by mass of the obtained colored particles and mixed using a Henschel mixer. Thus, a toner was obtained.
Hereinafter, the toners using the charge control agent (1) to the charge control agent (8) as the charge control agent will be referred to as toner (1) to toner (8), respectively, and the comparison charge control agent (1) to comparative example. The toners using the charge control agent (2) are referred to as comparative toner (1) to comparative toner (2), respectively.

Each toner obtained was mixed with a carrier made of light metal ferrite coated with a silicone resin having a volume average particle diameter of 65 μm to obtain a two-component developer having a toner concentration of 8%.
Hereinafter, the two-component developers using toner (1) to toner (8) as toners are referred to as developer (1) to developer (8), respectively, and comparison toner (1) to comparison toner (2). Are used as comparative developer (1) to comparative developer (2), respectively.

  With respect to the developer (1) to the developer (8) and the comparative developer (1) to the comparative developer (2) thus obtained, the toner charge rising characteristics, the toner charge stability and the formation are formed. The image quality was evaluated by the following method. The results are shown in Tables 1 to 3.

(1) Charging Rise Characteristics A toner and a carrier constituting each of developer (1) to developer (8) and comparative developer (1) to comparative developer (2) are placed in a glass tube having a volume of 20 ml. , 1 g of toner and 10 g of carrier are weighed and charged, and in a normal temperature and normal humidity (temperature 20 ° C., humidity 50% RH) environment, using a Yayoi shaker for 1 minute, 2 minutes, 5 minutes, 10 minutes, 20 minutes The charge amount after stirring for 60 minutes and 60 minutes was measured using a charge amount measuring device “TB-200” (manufactured by Toshiba) in a normal temperature and normal humidity environment.

(2) Charge stability A toner and a carrier constituting each of developer (1) to developer (8) and comparative developer (1) to comparative developer (2) are placed in a glass tube having a volume of 20 ml. 1 g of toner and 10 g of carrier were weighed and charged, and the charge amount (shown as “initial charge amount” in Table 1) was measured in a charge amount measuring device “TB-200” (manufactured by Toshiba Corporation) in a normal temperature and humidity environment. And then left in a high-temperature and high-humidity environment (temperature 35 ° C., humidity 85% RH) for 24 hours to measure the charge amount (shown as “charge amount after leaving” in Table 1) again. It was.

(3) Image quality Image is developed at a speed of 105 sheets per minute by the contact development method using each of developer (1) to developer (8) and comparative developer (1) to comparative developer (2). A copy machine capable of forming A4 size paper under normal temperature and normal humidity (temperature 20 ° C, humidity 50% RH) environment and high temperature and high humidity (temperature 35 ° C, humidity 85% RH) environment. Image formation on a total of 100,000 transfer sheets using an image formation mode in which the image formation operation is paused for one minute after image formation is continuously formed on 50 sheets of A4 size transfer paper with 5% pixel ratio. The initial image formed immediately after the start of the first image forming operation (indicated simply as “initial” in Tables 2 and 3) and the image formed in the 100,000th sheet (in Tables 2 and 3) Solid black image in simply “100,000”. The density of the image (shown as “image density” in Tables 2 and 3) and the fog density on the white background portion when the reflection density of the transfer paper was set to 0% using “RD-918” manufactured by Macbeth Co., Ltd. The relative reflection density was measured.
Further, the resolution of characters in the initial image and the image formed on the 100,000th sheet is visually confirmed, and the toner is charged after the initial image is formed and the image formed on the 100,000th sheet is formed. The amount was measured.

Claims (7)

A method for producing a charge control agent for obtaining a charge control agent comprising an azo metal complex,
An ion exchange reaction between an azo metal complex salt obtained by reacting a monoazo compound represented by the following general formula (1) and a complexing agent with an ammonium counter ion forming agent composed of urea and an inorganic ammonium salt is carried out as follows. The manufacturing method of the charge control agent characterized by having the process of synthesize | combining the azo type metal complex represented by General formula (2).

[In formula, Ar < ¹ > and Ar < ² > show an aromatic group each independently. ]

[In formula, Ar < ¹ > and Ar < ² > show an aromatic group each independently. M represents a trivalent metal atom. ]   The method for producing a charge control agent according to claim 1, wherein 3 to 20 equivalents of urea is used with respect to the azo metal complex salt.   The method for producing a charge control agent according to claim 1 or 2, wherein 0.5 to 2 equivalents of an inorganic ammonium salt is used with respect to the azo metal complex salt.   In the general formula (2) which shows an azo type metal complex, M is an iron atom, The manufacturing method of the charge control agent in any one of Claims 1-3 characterized by the above-mentioned.   The content of the azo metal complex represented by the general formula (2) in the reaction product obtained by ion-exchange reaction of the azo metal complex salt with the ammonium counter ion forming agent is 85% by mass or more. The method for producing a charge control agent according to any one of claims 1 to 4.   A charge control agent obtained by the method for producing a charge control agent according to any one of claims 1 to 5.   A toner comprising a charge control agent obtained by the method for producing a charge control agent according to claim 1.