JPH043432B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a metal complex salt compound and a toner for developing electrostatic latent images such as electrophotography and electrostatic recording. In electrophotography, a latent image is formed on a photoconductor made of a photoconductive substance, which is developed with a powder developer to become a visible image, and then transferred onto paper using heat, solvent, or in some cases pressure. The most common method is to establish The developer used in such electrophotography is a mixture of fine particle powder made of resin and colorant called developer powder or toner, and microscopic glass beads called carrier, iron powder, or iron powder whose surface has been treated with various resins. Ru. In this case, a developer using extremely fine ferrite or magnetite as a carrier is called a one-component developer, and can be distinguished from the former. The present invention relates to developer powder called toner of these developers. The photoconductor layer can be positively or negatively charged so that exposure under the original produces a positive or negative electrostatic latent image. Therefore, a positively charged positive image is generated on the negative electrostatic latent image. However, when a positively electrostatic latent image is developed with negatively charged developer powder, the black and white tones are reversed and a negative image of the original, that is, a positive negative image is obtained. As described above, there are two types of developer powder for electrophotography: positively charged developer powder and negatively charged developer powder. The present invention relates to negatively charged developer powder. Generally, developer powder is a fine powder made by mixing synthetic resin with coloring agents such as dyes and pigments. In order to charge the developing powder negatively, the dye mixed therein plays an important role not only in coloring but also in its electrostatic properties as a charge control agent. In particular, most of the dyes and pigments conventionally used as coloring agents are positively charged, and even if they are negatively charged, their chargeability is weak, resulting in mixed mirror images or fog, resulting in sharp images. I couldn't get an image. The present inventors focused on this point and developed a metal complex compound that has negative characteristics and particularly has extremely good compatibility with the resin used. As a result, it was possible to produce a developing powder with excellent electrostatic properties that improved all the drawbacks of conventionally used colorants. That is, the first invention of the present invention is based on the following formula [In the formula, X ₁ and X ₂ represent a hydrogen atom, a lower alkyl group, a lower alkoxy group, a nitro group, or a halogen atom, X ₁ and X ₂ may be the same or different, and m and m ' represents an integer of 1 to 2, R ₁ and R ₃ are hydrogen atoms, sulfonamides,
represents mesyl, sulfonic acid, carboxy ester or halogen atom, R ₁ and R ₃ may be the same or different, n and n' represent integers of 1 to 2, and R ₂ and R ₄ It represents a hydrogen atom or a nitro group, M represents a chromium, cobalt or iron atom, and A represents an aliphatic ammonium ion or a heterocyclic ammonium ion. ] The second invention is an electrophotographic developing powder containing a metal complex salt compound represented by the above general formula (1) as a charge control agent and a colorant. The above-mentioned metal complex salt compound has the property of being electrostatically negatively charged, and therefore, by mixing it with a suitable developing resin in a desired ratio, a negatively charged developing powder can be obtained very easily. In addition, there are many metal complex salt compounds similar to the compound represented by the above formula (1) as colorants for toners, as detailed below, but the compound according to the present invention is more suitable for developing powder than known compounds. It has particularly good compatibility with resins. Therefore, the developer powder is uniformly distributed in each of the fine particles. This is an important point regarding the charging characteristics of the developing powder. Furthermore, the dye of the present invention itself has an extremely large amount of negative charge. Regarding electrophotographic toners containing metal complex compounds, for example, Japanese Patent Publication No. 1973-20153, Japanese Patent Publication No. 43
-17955 and Japanese Patent Publication No. 43-27596, etc., the toner containing the metal complex compound represented by the general formula (1) of the present invention has a higher chargeability than those described in these publications. The toner has excellent properties and also shows negative results in the mutagenicity test (Ames test), making it suitable as an electrophotographic toner. On the other hand, the inventors have already developed an electrophotographic toner containing a metal complex compound as a similar compound.
No. 57-141452 and No. 58-111049, but compared to those inventions, the invention of the present application is due to the chemical structure of the counter ion and is not compatible with various resins, which are the biters that are the main component of toner. Due to its extremely good solubility, when used as an additive in electrophotographic toners, the toner has excellent charging stability during continuous copying, and has a large coloring power, resulting in extremely clear copied images and low gradation. I was able to obtain an excellent copy with good quality. The metal complex salt compound of the present invention was first disclosed in JP-A No. 58-
According to the description in Publication No. 111049, the following formula (In the formula, X ₁ , X ₂ , n, m and M are as defined in the above formula (1).) It can be easily obtained by salt formation treatment with an aliphatic amine, alicyclic amine or heterocyclic amine. Examples of amines that can be suitably used in the above salt-forming treatment include compounds represented by the following general formulas (3) and (4). (In the formula, R ₅ , R ₆ , R ₇ are hydrogen atoms, alkyl groups, halogen atoms, hydroxyl groups, alkoxy groups, amino groups, alkyl-substituted amino groups, phenyl groups, naphthyl groups, alkyl groups substituted with heterocyclic groups) , is an alkenyl group, R ₁ and R ₂ can form a ring via a nitrogen atom, or can further contain a hetero atom and form a ring via a nitrogen atom,
R ₅ , R ₆ and R ₇ may be the same or different. However, cases in which R ₅ , R ₆ , and R ₇ are all hydrogen atoms are excluded. ) (In the formula, R ₈ , R ₉ , R ₁₀ , R ₁₁ are an alkyl group or an alkyl group substituted with a halogen atom, a hydroxyl group, an alkoxy group, an amino group, an alkyl-substituted amino group, a phenyl group, a naphthyl group, a heterocyclic group) , is an alkenyl group, R ₅ and R ₆ can form a ring via a nitrogen atom, or can further contain a hetero atom and form a ring via a nitrogen atom,
R ₈ , R ₉ , R ₁₀ and R ₁₁ may be the same or different, and Y represents a residue of an onium compound such as a halogen atom or a sulfonic acid group. ) More specifically, for example, the compounds shown below can be mentioned. H ₂ NC ₄ H ₉ , H ₂ NC ₁₂ H ₂₅ , H ₂ NC ₁₈ H ₃₇ ,

【formula】

[Formula] HN (-C ₄ H ₉ ) ₂ ,

【formula】

[Formula] (CH ₃ )-N (-C ₁₂ H ₂₅ ) ₂ ,

【formula】

【formula】

【formula】

【formula】

_{HN ( -C3H6OC10H21 ) 2} , _H2N- ( _CH2 ) ₃ -O-( _CH2 ) _{7CH3 ,} ( _C3H7 ) _-2N- ( _CH2 ) _{4- CH} =CH _{- CH2CH3} , ( _C4H9 )-NH( _-CH2 ) _-2CH =CH- _{CH3 ,}

【formula】

N-( _C2H5 ) ₄・C _, ( _CH3 )-N- _{C12H25 ・}Br
， In addition to the metal complex compound, the toner of the present invention also contains:
The toner of the present invention contains a binding substance and a coloring substance, and examples of the binding substance suitably used in the toner of the present invention include monomers of styrene and its substituted products such as polystyrene and polyvinyltoluene, styrene-substituted styrene copolymers, Styrene-acrylic ester copolymer, styrene-methacrylic ester copolymer, styrene-acrylonitrile copolymer,
Polyvinyl chloride, polyethylene, silicone resin, polyester, polyurethane, polyamide,
Epoxy resins, modified rosins, phenolic resins, etc. can be used alone or in combination. Examples of coloring substances include CI Pigment Yellow 12, CI Solvent Yellow 16, CI Disperse Yellow 33, CI Pigment Red 122,
CI Solvent Red 19, CI Pigment Blue
15, CI Pigment Black 1, CI Solvent Black 3, CI Solvent Black 22, Carbon Black, etc. can be used. Another feature of the present invention is that by using it in combination with a colored dye that has the effect of a conventionally known charge control agent, the drawback of lack of long-term stability of known charge control agents can be significantly improved. Hereinafter, the present invention will be explained in detail with reference to Examples, where parts are parts by weight. Example 1 14.4 parts of 4-chloro-2-aminophenol
After stirring with 26 parts of concentrated hydrochloric acid and 400 parts of water,
The mixture was cooled on ice to a temperature of 0 to 5°C, 6.9 parts of sodium nitrite was added, and the mixture was stirred at the same temperature for 2 hours to diazotize. This diazotide was mixed with 300 parts of water, 10 parts of sodium hydroxide and 29.3 parts of 3-hydroxy-2 at 0 to 5°C.
After injecting into a mixture of -naphtho-0-anisidite and carrying out a coupling reaction, a monoazo compound having the following structural formula was isolated. A paste of this monoazo compound was dissolved in 120 parts of ethylene glycol, 5 parts of sodium hydroxide and 17.4 parts of sodium chromium salicylate were added, and the mixture was stirred at 110 to 120°C for 3 hours to perform chromation, and then cooled to room temperature. The precipitated product was filtered and the isolated wet cake was again dispersed in 400 parts of water. Next, a solution of 9.4 parts of 2-ethylhexyloxypropylamine, 5.2 parts of concentrated hydrochloric acid, and 50 parts of water was added, stirred at 40-50℃ for 1 hour, and the product was isolated by filtration, and the product was isolated under reduced pressure at 50-60℃. After drying, 55 parts of a fine black powder of a chromium complex salt compound represented by the following formula was obtained. When this chromium complex salt compound was dissolved in dimethylamide, it exhibited a black color (maximum absorption wavelength 576 nm). Manufacture of toner: Add 7 parts of carbon black and 1.2 parts of the chromium complex compound synthesized above to 100 parts of styrene-acrylic copolymer resin, mix well, melt by heating, cool, and grind in a ball mill to form a negatively charged fine powder. A developing powder (A) was obtained. On the other hand, as a comparison, 2-
A developing powder (B) was obtained by carrying out the same treatment using a complex salt compound before salt formation treatment with ethylhexyloxypropylamine. Regarding this developing powder (A) and (B),
Diameter for items left in 80% humidity for one week
Mix with 100-150μ iron powder at a weight ratio of 5:100,
When the specific charge amount of each was measured using a blow-off device (manufactured by Toshiba Chemical Co., Ltd.), the following results were obtained.

[Table] From this, iron salt compounds made with amines are
It is clear that the toner is extremely stable against humidity. Next, a positive electrostatic latent image is formed on a selenium photosensitive plate charged by corona discharge (+5000V), and this positive image is transferred to paper and heat-fixed to create a clear halftone image without fogging. Clear images can be obtained, and continuous copying (running)9
Even after the 10,000th copy, there was almost no change in the development characteristics of the toner, and a good copy that was the same as the initial image was obtained. In addition, the amount of charge on the toner was measured using the blow-off method, and the initial charge
The charge amount of the toner at the 90,000th sheet of running was -25.5μc/g, which was almost the same as the initial value, and the charge distribution was -22.4.
It was approximately uniform at ~-23.2 μc/g, and all were extremely excellent as toners. Next, as a comparative example, when the following known metal complex compound described in JP-A-58-111049 was used instead of the metal complex compound of the present invention, In particular, in continuous copying, it was possible to obtain clear images without any change in development characteristics from the initial to the 30,000th copy, but at the 90,000th copy, the amount of charge on the toner decreased compared to the initial value (-21.2μc/g). Significantly lower (−
15.3 μc/g), and at the same time, the image became unclear with background stains. Examples 2 to 10 Metal complex salt compounds were synthesized according to Example 1, and toners were obtained by the same operation as Example 1 with the developer composition shown in the following table. They are also summarized in the table.

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

[Table] Example 11 Synthesis of metal complex compound; Dissolve the paste of the monoazo compound synthesized in Example 1 in 150 parts of ethylene glycol, then add 10 parts of concentrated sulfuric acid and 54 parts of 40% chromium sulfate aqueous solution, After chromating by stirring at 100°C for 3 hours, a paste of the following monoazo compound synthesized on a 0.1 molar scale according to Example 1 was added, 12 parts of sodium hydroxide and 11 parts of sodium acetate were added and stirred at 95-100°C for 2 hours to produce an asymmetric 1:2 type chromium complex salt compound, and the precipitated product was filtered and isolated at room temperature. The wet cake was again dispersed in 800 parts of water. Next, a solution of 19 parts of 2-ethylhexyloxypropylamine dissolved in 11 parts of concentrated hydrochloric acid and 100 parts of water was added, stirred at 40-50°C for 1 hour, and the product was isolated by filtration, and the product was isolated under reduced pressure at 50-60°C. After drying, 108.2 parts of a black fine powder chromium complex compound represented by the following formula was obtained. When this chromium complex salt compound was dissolved in dimethylformamide, it exhibited a black color (maximum absorption wavelength 570 nm). Manufacture of toner: Using this chromium complex salt compound, the same treatment as in Example 1 was carried out to obtain a developer. Next, a positive electrostatic latent image is formed on a selenium photosensitive plate charged by corona discharge (+5000V), and this positive image is transferred to paper and heat-fixed to create a clear halftone image without fogging. Clear images can be obtained, and continuous copying (running)9
Even after the 10,000th copy, there was almost no change in the development characteristics of the toner, and a good copy that was the same as the initial image was obtained. In addition, the amount of charge on the toner was measured using the blow-off method, and the initial charge
The charge amount of the toner at the 90,000th sheet of running is -21.0μc/g, which is almost the same as the initial value, and the charge distribution is -21.0 ~
-21.4 μc/g, which was almost uniform, and all were extremely excellent as toners. By using the metal complex salt compound shown below instead of the chromium complex salt compound of Example 11, an extremely excellent toner could be obtained in the same manner as in Example 11. Example 12 Example 13

Claims (1)

[Claims] 1. The following general formula [In the formula, X ₁ and X ₂ represent a hydrogen atom, a lower alkyl group, a lower alkoxy group, a nitro group, or a halogen atom, X ₁ and X ₂ may be the same or different, and m and m ' represents an integer of 1 to 2, R ₁ and R ₃ are hydrogen atoms, sulfonamides,
represents mesyl, sulfonic acid, carboxy ester or halogen atom, R ₁ and R ₃ may be the same or different, n and n' represent integers of 1 to 2, and R ₂ and R ₄ It represents a hydrogen atom or a nitro group, M represents a chromium, cobalt or iron atom, and A represents an aliphatic ammonium ion or a heterocyclic ammonium ion. ] A metal complex compound represented by 2 General formula below [In the formula, X ₁ and X ₂ represent a hydrogen atom, a lower alkyl group, a lower alkoxy group, a nitro group, or a halogen atom, X ₁ and X ₂ may be the same or different, and m and m ' represents an integer of 1 to 2, R ₁ and R ₃ are hydrogen atoms, sulfonamides,
Represents mesyl, sulfonic acid, carboxy ester or halogen atom, R ₁ and R ₃ may be the same or different, n and n' represent integers of 1 to 2, and R ₂ and R ₄ are hydrogen atoms. or a nitro group, M represents a chromium, cobalt or iron atom, and A represents an aliphatic ammonium ion or a heterocyclic ammonium ion. ] An electrophotographic toner comprising a metal complex compound represented by: