JP3392479B2 - Method for producing metal complex dye and electrophotographic toner containing the dye - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a metal complex salt dye useful for a toner which is a developer for electrophotography, and an electrophotographic toner containing the metal complex salt dye.

[0002]

2. Description of the Related Art In an electrophotographic image forming process, an electrostatic latent image is formed on an inorganic photoreceptor such as selenium, a selenium alloy, cadmium sulfide, or amorphous silicon, or an organic photoreceptor using a charge generating agent and a charge transporting agent. It is formed, developed with toner, transferred to paper or a plastic film, and fixed to obtain a visible image.

The photosensitive member has a positive charging property and a negative charging property depending on its constitution. When the printing portion is left as an electrostatic latent image by exposure, it is developed with a toner of opposite sign charging, while the printing portion is discharged. When reversal development is performed, development is performed with a chargeable toner having the same sign. Toner is composed of binder resin, colorant and other additives.
A charge control agent is generally used in order to impart (charge rate, charge level, charge stability, etc.), stability over time, and environmental safety. The characteristics of the toner are greatly affected by this charge control agent.

The two-component toner is charged by friction with the carrier. Also, the one-component toner is charged by friction with the sleeve. The charged toner is
Develop the latent image on the photoreceptor. 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.

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 addition of a charge control agent has been used to obtain the desired tribocharging characteristics. 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 stirring in the developing section, but the higher the speed of the machine, the faster the replenished toner is transferred from the developing section to the photosensitive member, 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.

Conventionally, as charge control agents, for example, nigrosine, aniline black, phthalocyanine pigments and metal complex salt dyes have been known, but the proposed charge control agents have a compatibility with resins and produce toners. At that time, it does not mix well with the resin, 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. Conventionally, many metal complex salt dyes have been known as toners for electrophotography.

For example, an electrophotographic toner containing a metal complex dye is disclosed in JP-A-57-141452 and JP-A-5-141452.
8-111049, JP 61-101558, JP 61-155463, JP 61-
155464, JP 62-177561, JP 62-116946, JP 2-15.
Although disclosed in Japanese Patent No. 3362, etc., the toners using the proposed metal complex salt dyes still have a problem that they show behavior such as instability of electric charge at high temperature and high humidity, and still remain. It is not satisfactory as a charge control agent for toner.

[0011]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, has a good rise in charging, is not affected by changes in temperature and humidity even when repeated and developed by continuous use, and has a long life. It is an object of the present invention to provide a toner with good performance capable of reproducing an image that is stable over time.

[0012]

As a result of various studies to solve these problems, the present inventors have found that the exchange rate with respect to the equivalent of NH ₄ ⁺ or ammonium compound cation which is a counter ion of a metal complex salt dye is high. In the case of the ratio, it is found that the dispersibility is extremely good, and the toner using the metal complex salt dye has the above-mentioned problem, that is, the rising of charging is accelerated and the charging performance is improved. The present invention has been completed on the basis that it is intended to solve the problems such as stabilization and prevention of toner scattering and image defects.

That is, in the present invention, the NH ₄ ⁺ or ammonium compound cation in the cation portion is 80% based on the equivalent amount.
General formula (1) characterized by the above

[0014]

[Chemical 3]

{In the formula (1), m represents an integer of 1 to 3. R _1-6 may be the same or different and may be a hydrogen atom, a C _1-30 alkyl group, a C _1-30 alkoxy group, a C _1-30 alkylsulfone group, or a C _1-30 alkylamino. Sulfone group, acetylamino group, sulfonamide group, benzoylamino group, phenylsulfone group,
Halogen atom, hydroxyl group, _-COOH, -SO 3 H, -C
OOR ₁₁ [R ₁₁ is a C _6-30 aryl group, or C
_1-30 alkyl group], -CONHR ₁₂ , [R _{12
Represents} a C _6-30 aryl group, or a C _1-30 alkyl group], and -CON (R ₁₃ ) ₂ [R ₁₃ represents a C _1-30 alkyl group]. M represents Fe. Also, X ₁ ⁺ is N
H ₄ ⁺ or an ammonium compound cation represented by the following general formula (2) is represented. }

[0016]

[Chemical 4]

[In the formula, n ₁ represents an integer of ₁ to 3. R
Each of _14-17 represents a hydrogen atom, a C _1-30 alkyl group, a C _7-30 aralkyl group, a C _6-30 aryl group, and an amino group, an ether group, a thioether group or an alkoxy group in each group. Group, hydroxyl group, carboxylic acid amide group, sulfamide group, urethane group, chloromethyl group, nitro group, halogen atom (F, Cl, Br), C
Aromatic groups _6-30, aromatic heterocyclic group _{C 6-30,} may include one or more. Also, a quaternized amino group may be contained in the group of R _14-17 . Also R
Two of _14-17 may combine with each other to form an alicyclic ring or an aromatic ring. ] The manufacturing method of the metal complex salt dye represented by these, and the toner for electrophotography characterized by containing this dye.

The metal complex salt dye of the general formula (1) is usually a diazotized and coupled monoazo compound obtained by a known method, and the metal complex salt dye obtained by complexing the metal with ammonia water or an ammonium compound is used. It was supposed to be obtained by processing. However, the metal complex salt dye of the formula (1) thus obtained can obtain only the NH ₄ ⁺ or ammonium compound cation exchange rate of 20 to 60% based on the equivalent amount.

As the metal complex chlorinating agent used in the metal complex chlorination reaction, known compounds are used. For example, ferric acetate, ferric sulfate, ferric chloride and the like can be mentioned. The amount used is preferably in the range of 0.5 to 10 mol with respect to 1 mol of the aminophenol compound. In addition, salicylic acid may be used during the metal complex chloride reaction. The amount used is preferably 0.01 to 10 mol per 1 mol of the aminophenol compound.

As described above, the excellent dispersibility in the resin is intended to solve the problems of accelerating the rise of charging, stabilizing the charging performance, and preventing toner scattering and image defects. Requires that the exchange rate of NH ₄ ⁺ or ammonium compound cations in the metal complex salt dye of the general formula (1) is 80% or more based on the equivalent amount. As a result of intensive studies on this point, the present inventors have concluded that, in order to achieve this object, it is necessary to use an ammonium compound for treating a metal complex salt dye in an amount more than a theoretical amount. . That is, the amount of the ammonium compound used should be 1.1 to 10 equivalents. Alternatively, the metal complex dye may be treated once with ammonia or an ammonium compound, then filtered, and the press cake may be dispersed again in a solvent such as water, glycol, methanol, or acetone, and then treated again with the ammonium compound to obtain a counterion exchange rate. 80
It can be raised to over%. When exchanging the cation part of the metal complex iron dye with NH ₄ ⁺ , it is also possible to use inorganic ammonium such as ammonium nitrate, ammonium phosphate, ammonium bicarbonate, ammonium chloride and ammonium sulfate.

The metal complex salt iron dye of the present invention described above has good dispersibility in a resin, and a toner using the metal complex salt dye has a good start-up of charging and is capable of operating under conditions of low temperature and low humidity and high temperature and high humidity. Therefore, even if the toner is used for a long period of time, it is possible to solve the problems of toner charging instability and toner scattering, which results in a clear developed image.

In a general method for producing a two-component toner, a binder resin is put into a ball mill or other mixer prior to a mixer, a colorant, a charge control agent and a wax are added and premixed, followed by a heating roll, a kneader, Kneading is generally performed at a temperature of 150 ° C. or lower with an extruder or the like. After further pulverization, classification is carried out to obtain a toner of 5 to 25 μm. On the other hand, in the one-component toner, magnetic powder is used instead of the colorant, and the toner is obtained by the above method. Further, a method of adding magnetic powder to a two-component toner is disclosed.

The present invention is characterized in that the metal complex salt dye of the present invention is used as the charge control agent. As a method of adding the above compound to the toner, there are a method of adding inside the toner and a method of adding externally, but it is usually preferable to add internally. When internally added, the amount of these compounds used is determined by the kind of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method, and is uniquely limited. It is not a thing, but 0.1-15 per toner weight considering other performance.
It is used in an amount of 0.5% by weight, preferably 0.5 to 10% by weight. When externally added, it is 0.01 per toner weight.
-10 wt% is preferable. The metal complex salt dye is 0.1 to
25 μm particles are preferred.

Preferred as the binder resin for toner are polymers of styrene such as polystyrene and polyvinyltoluene and their substitution products, styrene-substituted styrene copolymers, styrene-acrylic acid ester copolymers, styrene- Methacrylic acid ester-based copolymer,
Styrene-acrylonitrile copolymer, polyvinyl chloride type, polyethylene, polyester, silicone resin, polyester, polyurethane, polyamide, epoxy resin, modified rosin, phenol resin and the like can be used alone or in combination.

In order to improve the fixing property, for example, low molecular weight polyethylene, low molecular weight polybutene, low molecular weight polypropylene, or maleic acid ethyl ester, maleic acid butyl ester, stearic acid ethyl ester, stearic acid butyl ester, palmitic acid cetyl ester. Resin acid esters such as amide waxes, amide waxes such as stearic acid amides, oleic acid amides, palmitic acid amides, lauric acid amides, and ethylenebisstearylamide, carnauba wax, and the like can be used.

As the coloring substance, for example, C.I. I. Pigment Yellow 12, C.I. I. Solvent yellow 1
8, C.I. I. Day Birds 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 applicable. The amount of these compounds in the toner as a coloring substance is preferably 3 to 10% by weight.

In the present invention, the toner powder of the present invention is prepared by melt blending the charge control agent in a weight ratio of 0.1 to 50% by weight with respect to the binder resin, solidifying the mixture, and then using a hammer mill or other pulverizer. Coarse pulverization, further fine pulverization with a jet mill pulverizer, then classify with an air stream classifier, or add a polymerization initiator to the binder resin monomer, and add this charge control agent to the monomer by weight. 0.1 to 0.1
It can be produced by adding in the range of 50% and polymerizing the mixture while suspending it in water. At this time, a dye or carbon may be added as a coloring agent.

Further, the toner of the present invention gives better results than the case where additives are mixed if necessary. Examples of the additive include lubricants such as Teflon and zinc stearate, abrasives such as cerium oxide and silicon carbide, fluidity imparting agents such as colloidal silica and aluminum oxide, anti-caking agents, or carbon black and tin oxide. And the like, or fixing aids such as low molecular weight polyethylene. These additives will further enhance the effects of the present invention when those having the same polarity as the toner or exhibiting almost no charge are used.

The toner thus produced gives a charge amount suitable for developing an electrostatic image due to 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. Known carriers include iron powder, magnetic core coated with styrene-methylmethacrylate copolymer, silicone resin, mixed resin of styrene-methylmethacrylate copolymer and silicone resin, carrier coated with tetrafluorostyrene polymer, etc. All can be used.

Further, the metal complex salt dye according to the present invention gives excellent charging characteristics even when used in a so-called one-component toner containing magnetic powder. It can also be used as a capsule toner and a polymerized toner. As the magnetic material used as the magnetic powder, fine metal powder such as iron, nickel and cobalt, iron, cobalt, copper, aluminum and nickel,
Alloys of metals such as zinc, aluminum oxide, iron oxide,
Metal oxides such as titanium oxide, ferrites such as iron, manganese, nickel, cobalt, zinc, vanadium nitride, nitrides such as chromium nitride, tungsten carbide, carbides such as silicon carbide and mixtures thereof. Can be used. As the magnetic powder, iron oxide such as magnetite, hematite and ferrite is preferable.

Hereinafter, the present invention will be described in detail with reference to production examples of metal complex salt dyes having a high counterion exchange rate and use examples as toners, but the present invention is limited by these examples. Not something. The amounts and parts of each component described in the examples are parts by weight unless otherwise specified.

Production Example 1 After stirring 14.4 parts of 2-aminophenol with 20 parts of concentrated hydrochloric acid and 100 parts of water, the mixture was ice-cooled to 0 to 5 ° C., and 6.9 parts of sodium nitrite was added. The mixture was stirred at the temperature for 2 hours to be diazotized. This diazotized product was poured into a mixed solution of 300 parts of water, 10 parts of sodium hydroxide and 26.3 parts of 3-hydroxy-2-naphthanilide at 0 to 5 ° C. to conduct a coupling reaction, and then the following is shown. A monoazo compound having the structural formula was isolated.

[0033]

[Chemical 5]

This paste of the monoazo compound is dissolved in 150 parts of ethylene glycol, 5 parts of sodium hydroxide and 8.5 parts of ferric chloride are added, and 110-120 are added.
The mixture was stirred at ℃ for 2 hours to carry out complex chlorination, then cooled to room temperature, the precipitated product was separated by filtration, and the isolated wet cake was dispersed again in 400 parts of water. Next, 13.4 parts of ammonium chloride (5 equivalents) was added and the mixture was stirred for 1 hour to isolate the product by filtration and dried to obtain a black-brown fine powder of iron complex salt dye (compound 1) represented by the following formula. .

[0035]

[Chemical 6]

{In compound 1, X ₂ is H ⁺ , Na ⁺
Or NH ₄ ⁺ }

As a result of elemental analysis of this compound 1, 99% of NH ₄ ⁺ body having counter ion NH ₄ ⁺ was contained.

Comparative Production Example 1 An iron complex salt dye was synthesized in the same manner as in Production Example 1 except that the amount of ammonium chloride used was changed to 2.7 parts (1 equivalent). The obtained wet cake of the iron complex salt dye was dried to obtain a black-brown fine powder of the iron complex salt dye (Compound 2). As a result of elemental analysis of this compound 2, N having a counter ion of NH ₄ ⁺
20% of H ₄ ⁺ bodies were contained.

[0039]

[Chemical 7]

{In compound 2, X ₃ is H ⁺ , Na ⁺ or NH ₄ ⁺ }

Example 1 88 parts of styrene-n-butylmethacrylate copolymer resin (manufactured by Heimer TB-1000 Sanyo Kasei Co., Ltd.), 5 parts of low molecular weight polypropylene [Viscor 550-P manufactured by Sanyo Kasei Co., Ltd.], carbon [# 44 Mitsubishi Kasei Co., Ltd.]
5 parts of compound 1 and 2 parts of compound 1 were put into a chemical mixer, pre-mixed for 10 minutes, melt-kneaded at 120 ° C. using a hot roll mill, further pulverized and classified to have a particle size of 5 to 25 μm.
Got m toner. A developer was prepared by mixing 97 parts of a silicon-coated ferrite carrier with 3 parts of this toner. Also, when this toner was put in a developing device and continuous copying was performed and an image test was performed, a good image was obtained at the start, and the image quality did not change after 50,000 sheets,
No toner scattering or offset occurred. 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. In addition, toner scattering and offset did not occur.

Comparative Example 1 A toner was prepared in the same manner as in Example 1 except that Compound 2 was used instead of Compound 1. Further, an image test was conducted in the same manner as in Example 1. As a result, a clear image free of fog was obtained as the initial image, but from about 1000 sheets, it became an unclear image with fog.

In the same manner as in Production Example 1, a complex chlorination reaction was carried out using ferric chloride as the metal complex chlorinating agent. Further, at the time of cation exchange, 5 equivalents of ammonium chloride or amine compound was used with respect to the aminophenol compound to perform cation exchange to produce compounds 3, 4 and 5, which were used in Examples 2, 3 and 4. Further, as in the case of producing Compound 2 in Comparative Production Example 1, after complexing with ferric chloride as a complexing agent, cation exchange was performed using 1 equivalent of ammonium chloride or amine compound to obtain Compounds 6, 7, 8 was produced and used in Comparative Examples 2, 3, and 4. The results are shown in Tables 1 and 2. In Tables 1 and 2, the binder resin used and the judgment criteria for each evaluation item are as follows.

Binder resin A: Styrene-acrylic acid copolymer [Heimer 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.
Manufacturing] D: Polyester [HP-320 Nippon Synthetic Chemical Industry Co., Ltd.
Manufactured]

Judgment: ○ indicates no practical problem, × indicates practical problem

[0046]

[Table 1]

[0047]

[Table 2]

[0048]

From each of the examples and comparative examples, when the exchange rate of NH ₄ ⁺ or ammonium compound cation in the metal complex salt dye is 80% or more based on the equivalent weight, the dispersion of the metal complex salt dye in the resin is extremely high. It can be seen that each toner particle has 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 is a TEM (transmission electron microscope) photograph showing the dispersion state of Compound 1 in a binder resin.

FIG. 2 is a TEM (transmission electron microscope) photograph showing the dispersion state of Compound 2 in a binder resin.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-155463 (JP, A) JP-A-63-81165 (JP, A) JP-A-50-156541 (JP, A) JP-A-61- 101558 (JP, A) JP-B 41-12915 (JP, B1) (58) Fields investigated (Int.Cl. ⁷ , DB name) C09B 45/00 C09B 67/00 G03G 9/00

Claims (5)

(57) [Claims] 1. In an exchange reaction of a cation part of a metal complex dye, an ammonium compound is added in an amount of 1.1 to 10 relative to an equivalent amount.
By using a double amount, the NH ₄ ⁺ or ammonium compound cation in the cation part is 80 to 1 with respect to the equivalent amount.
Method for producing a metal complex salt dye represented by the general formula (1) characterized by containing 100% {In the formula (1), R _1-6 may be the same or different, and a hydrogen atom, a C _1-30 alkyl group, C
_1-30 alkoxy group, C _1-30 alkylsulfone group, C _1-30 alkylaminosulfone group, acetylamino group, sulfonamide group, benzoylamino group,
Phenyl sulfone group, halogen atom, hydroxyl group, -COO
_H, -SO 3 _H, -COOR _{11 [R 11} is _{C 6-30}
Aryl group or C _1-30 alkyl group], —CO
NHR ₁₂ , [R ₁₂ is a C _6-30 aryl group or a C _1-30 alkyl group], -CON (R ₁₃ ) ₂ [R
₁₃ represents a C _1-30 alkyl group]. M represents Fe. X ₁ represents NH ₄ ⁺ or an ammonium compound cation represented by the general formula (2). [Chemical 2] Wherein, _{n 1} represents an integer of 1-3. R _14-17 are each a hydrogen atom, a C _1-30 alkyl group, C
_7-30 aralkyl group and C _6-30 aryl group, each of which has an amino group, an ether group, a thioether group, an alkoxy group, a hydroxyl group, a carboxylic acid amide group, a sulfamido group, a urethane group, and a chloromethyl group. , Nitro group, halogen atom (F, Cl, Br), C _6-30
1 to more than one of the aromatic groups described above and C _6-30 aromatic heterocyclic groups. Also, in the group of R _14-17 , 4
It may contain a graded amino group. Two R _14-17 may be bonded to each other to form an alicyclic ring or an aromatic ring. ] Is represented. } 2. The ammonium compound is ammonium nitrate,
The method for producing a metal complex salt dye according to claim 1, which is an inorganic ammonium selected from ammonium phosphate, ammonium bicarbonate, ammonium chloride and ammonium sulfate, wherein X ₁ ⁺ in the general formula (1) is NH ₄ ^+. 3. The method for producing a metal complex dye according to claim 1, wherein in the exchange reaction of the cation part of the metal complex dye, the ammonium compound is used after the completion of the metal chlorination reaction. 4. The metal according to claim 1, wherein in the exchange reaction of the cation portion of the metal complex salt dye, the method of using the ammonium compound is a method of adding the press cake of the metal complex salt dye after dispersing in a solvent. Complex salt dye manufacturing method 5. An electrostatic charge image developing toner containing the metal complex salt dye represented by the general formula (1) obtained by the method according to any one of claims 1 to 4.