JPH07225493A - Electrophotographic toner - Google Patents

Abstract

PURPOSE:To obtain a toner whose extent of electrostatic charge is almost independent of the temp. and the humidity by incorporating a specified compd. CONSTITUTION:A compd. having the structure of an arom. carboxylate represented by the formula is incorporated. In the formula, -X is -NH2, -N[(CH2)lCH3]2 [(l) is an integer of 0-16], -(CH2)l'CH3 (l' is an integer of 0-16), -O(CH2)l''CH3 (l'' is an integer of 0-16), -F, -Cl, -Br, -I, -CN, -NO2 or -OC6H5, -Y is -H, -(CH2)mCH3 [(m) is an integer of 0-16], -CH(CH3)2, -C(CH3)3 or -O-(CH2)m' (m' is an integer of 0-16), M is a metallic element such as Zn, Cu, Ni, Fe, Sn, Mn, Ti, Co, Ga, Ge or In and (n) corresponds to the valence of M.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electrophotographic toner for laser printers, copying machines and the like.

[0002]

2. Description of the Related Art Various image forming methods utilizing electrostatic phenomenon in laser printers, copying machines and the like are described in US Pat. No. 2,297,691 and Japanese Patent Publication No. 42-23910. For example, a process of adsorbing a toner, which is a developer, on an electrostatic latent image formed on a photoreceptor, then transferring the toner to a transfer material, and then fixing the toner is performed. At this time, in order to obtain a clear developed image without fog or the like, it is important for the toner to have an appropriate charging property. Therefore, until now, various charge control agents (hereinafter, abbreviated as CCA) have been added to toners to optimize their chargeability. Further, the amount of charge required for the toner differs depending on the device that uses the toner. Therefore, many compounds such as triphenylmethane derivatives, nigrosine, and metal salts of monoazo dyes have been studied as CCA. However, since many of these compounds are colored, they are not suitable for color toner when the addition amount is large. Therefore, in recent years, metal salts of oxycarboxylic acids such as salicylic acid have been aimed at for color images (JP-A-53-127726).
No.), various quaternary ammonium salts, colorless or light-colored compounds such as amine compounds such as imidazole derivatives have been investigated.

[0003]

However, since many of these colorless or light-colored compounds are easily colored in the air and are easily affected by humidity, the types of compounds that can actually be used are considerably small. This has been an obstacle in producing a toner having a charge amount suitable for each developing device. An object of the present invention is to provide a toner having a low colorability and a charge amount less susceptible to temperature and humidity.

[0004]

Means for Solving the Problems As a result of intensive studies on the above problems, the present inventors have found that the compounds having an aromatic carboxylate structure shown below are effective as CCA of toner and have low colorability. The present invention has been found to have high moisture resistance and has led to the present invention.

[0005]

[Chemical 2]

Here, -X is -NH ₂ , -N ((CH ₂ ) _l
CH _{3) 2} (provided that l is an integer from 0 to 16), - (CH _2)
l' CH ₃ (where l'is an integer from 0 to 16), -O (C
H ₂ ) _{l ″} CH ₃ (where l ″ is an integer from 0 to 16), −
F, -Cl, -Br, -I, -CN, -NO 2, or a -OC ₆ H _5.

Further, -Y is -H, - (CH ₂₎ (integer where m is from _{0 16) m CH 3, -} CH (CH 3) 2, -C
(CH _{3) 3,} or a _{-O- (CH 2) m 'CH} 3 ( provided that m' is an integer from 0 to 16).

Further, M represents a metal element, specifically, Zn, Cu, Ni, Fe, Sn, Mn, Ti, Co, G
Examples include a, Ge, and In. Further, n corresponds to the valence of M.

[0009]

The present invention relates to CCA or a toner containing the above-mentioned aromatic carboxylic acid salt as a part of CCA.

Of the normal CCA's, one that charges the toner in the positive direction is called a positive CCA, and one that charges the toner in the negative direction is called a negative CCA. Of the above compounds, those in which X is a residue having an electron-donating property tend to act as a positive CCA. Also, if X is an electron-withdrawing residue, negative CCA
Tends to act as. That is, X is NH ₂ , N
_{((CH 2) l CH 3} ) _2, then the compound tends to function as a positive CCA. X is F, Cl, Br, I,
In the case of CN, NO ₂ , the compounds tend to act as negative CCA.

In the present invention, X is preferably F, Cl, Br, I, CN or NO _{2 in} order to suppress the hygroscopicity of the compound.
When X is a hydroxyl group, it is considered that hygroscopicity appears.

When Y has an alkyl group, the compatibility with the resin is better. Also, the longer the length, the better the compatibility. However, if it is too long (for example, Y is (CH ₂ ) _m
CH ₃ when m is 10 or more, or Y is O (CH ₂ ).
_{When m ′} is 10 or more in _{m ′} CH ₃ ), the function as CCA tends to decrease. Further, the melting point is also lowered (for example, when Y is-(CH ₂ ) _m CH ₃ and m is 12 or more,
Alternatively, when Y is O (CH ₂ ) _{m ′} CH ₃ and m ′ is 12 or more) and a toner containing this is used in an apparatus having a high fixing temperature, offset may occur. To avoid this, a method of applying silicone oil to the fixing roll can be considered. By using this method, m and m '
Can be used up to about 16.

Further, X is (CH ₂ ) _l' CH ₃ (where l '
Is 0, an integer of 0 to 16), and O (CH ₂ ) _{l ″} CH ₃ (where l ″ is an integer of 0 to 16), Y is H, (CH ₂ ) _m C
H ₃ (where m is an integer from 0 to 10), CH (CH ₃ ) ₂ ,
C (CH ₃ ) ₃ or O (CH ₂ ) _{m ′} CH ₃ (provided that m ′
Is preferably an integer of 0 to 10). This is also because if m or m ′ is too long, the function as CCA tends to deteriorate and the melting point also lowers, which may cause offset.

M represents a metal element, and Na, K, Mg,
When an element such as an alkali metal such as Ca or an alkaline earth metal is used, the hygroscopicity is large, and therefore a transition metal element is preferable if possible. Specifically, Zn, Cu, Ni, Fe,
Examples include Sn, Mn, Ti, Co, Ga, Ge, and In. Note that n corresponds to the valence of M, which is a metal element. For example, when M is Zn, Ni, etc., n is 2.
When Fe or the like, n is 2 or 3, and when Sn, Ge or the like, n is
Is 2 or 4.

The resin to be kneaded with the above charge control agent is
Examples thereof include polystyrene, styrene-acryl copolymer, styrene-alkyl methacrylate copolymer, and polyester.

As a colorant, carbon black may be added in the case of a black toner, and a colorant corresponding to an intended color may be added in the case of a color toner.

The mixing ratio (polymerization ratio) at the time of kneading the resin, the colorant, and the charge control agent varies depending on the developing machine to be applied and the coloring intensity of the colorant, but is approximately as follows.

Resin: Colorant: Charge control agent = 80 to 98:
1-10: 1-10

[0019]

EXAMPLES The present invention will be described with reference to examples.

(Example 1) Among the charge control agents of the present invention,
The chemical structure is as follows: X is NO ₂ group, Y is hydrogen, M
Represents a method for synthesizing a compound in which Zn is 2 and n is 2 (hereinafter referred to as compound 1).

[0021]

[Chemical 3]

3 parts by weight of potassium paranitrobenzoate was dissolved in 20 parts by weight of water, and 1 part by weight of zinc chloride was added to 10 parts of water.
What was melt | dissolved in weight part was dripped. The precipitated solid was collected by filtration and recrystallized from ethyl acetate-n-hexane to obtain about 2 parts by weight of a crystal of Compound 1 (yield: about 80).
%). Elemental analysis confirmed that this solid was the target compound 1. Compound 1 was a white crystal and did not change the color tone of the resin even when mixed with or dissolved in a toner resin such as styrene-acryl or polyester.

Next, the behavior of Compound 1 was investigated using a surface charge amount measuring device (TV-100VH manufactured by Toshiba Chemical). The measuring method is shown below.

First, a tetrahydrofuran solution having the following weight ratio was prepared.

Compound 1: 1 part by weight Styrene-acrylic resin (Tg = 65 ° C.): 99 parts by weight Tetrahydrofuran: 900 parts by weight After dropping this solution onto a stainless steel substrate dedicated to the above measuring device, the substrate was rapidly rotated at 1500 rpm. Spin for 1 minute. Then, the mixture was heated at 50 ° C. for 30 minutes and then at 100 ° C. for 1 hour to completely remove the tetrahydrofuran to prepare a sample for measuring the amount of charge. For comparison, a sample for measuring the charge amount was prepared by the same method using a tetrahydrofuran solution in which only the resin was dissolved without containing Compound 1. Using the charge amount of these samples as a carrier, FSL-
When measured using 2030 (manufactured by Powder Tech Co., Ltd.), the sample containing Compound 1 was -7.4 pC / sec. However, the sample containing no compound 1 is -0.2 pC.
/ Sec. The charge amount of these two samples was measured after leaving them in an atmosphere of a temperature of 30 ° C. and a humidity of 80% for 100 hours. The amount of the compound 1-containing sample was 7.2 pC / sec, and the amount of the compound 1-free sample was −0. .1 pC / sec
Met.

From the above, it was found that the compound 1 negatively charges the resin used and the amount of charge is stable even under high temperature and high humidity.

Next, the behavior of Compound 1 when used in a toner was investigated. Prepare the materials in the following weight ratios.

Compound 1 2 parts by weight Carbon black (MA-8 manufactured by Mitsubishi Kasei) 14 parts by weight Styrene-acrylic resin (Tg = 65 ° C.) 180 parts by weight Polypropylene 1 part by weight These are mixed with a Henschel mixer and mixed. -Heating and kneading with a der was repeated. Next, this kneaded material was roughly pulverized with a hammer mill, finely pulverized with a jet mill, and then pulverized with an air flow spheronizer to obtain fine powder having an average particle diameter of 10 μm. This fine powder was used as a toner. 1 part by weight of this fine powder and an average particle size of 6
15 parts by weight of 0 μm carrier was mixed to obtain a two-component developer. When this developer was tested on a commercially available copying machine, the image was clear even after copying 10,000 sheets.

When this developer was left in an atmosphere of a temperature of 30 ° C. and a humidity of 80% for 100 hours and then tested by the same copying machine, the image was clear even after copying 10,000 sheets.

From the above, it was confirmed that the resin fine powder containing the compound 1 can be used as a toner for electrophotography.

When the bulk Compound 1 was left at room temperature, it did not discolor after 100 hours and remained white. Then, it was left for 100 hours in an atmosphere of a temperature of 30 ° C. and a humidity of 80%, but it remained white. In addition, the increase in weight under the above atmosphere was within 3%, and no deliquescent due to moisture absorption was observed. From this, it was confirmed that the compound 1 was a compound excellent in environmental stability.

(Example 2) Among the charge control agents of the present invention,
In the chemical structure, X is a NO ₂ group and Y is CH.
_A method for synthesizing a compound having ₃ groups, M being Zn, and n being 2 (hereinafter referred to as compound 2) will be shown.

2 parts by weight of sodium hydroxide was dissolved in 50 parts by weight of water. To this, 8 parts by weight of 2-methyl-3-nitrobenzoic acid was added and then thoroughly stirred to completely dissolve it. A solution prepared by dissolving 3 parts by weight of zinc chloride in 20 parts by weight of water was added dropwise. The precipitated solid was collected by filtration and recrystallized from ethyl acetate-n-hexane to obtain about 5 parts by weight of a crystal of compound 2 (yield: about 50%). It was confirmed by elemental analysis that this solid was the target compound 2. Compound 2 was a pale yellow crystal and did not change the color tone of the resin even when mixed with or dissolved in a toner resin such as styrene-acrylic or polyester.

Next, the behavior of the compound 2 was investigated using a surface charge amount measuring device (TV-100VH manufactured by Toshiba Chemical).
The measuring method is the same as that of Example 1 except that the compound 2 (1 part by weight) is used instead of the compound 1 (1 part by weight) as the material that is dissolved in the tetrahydrofuran solution when the sample is prepared. When the charge amount of the created sample was measured, it was -7.6p.
It was C / sec. This sample has a temperature of 30 ° C and a humidity of 8
When the charge amount after standing for 100 hours in a 0% atmosphere was measured, it was -7.4 pC / sec.

From the above, it was found that the resin using the compound 2 was negatively charged, and the charge amount was stable under the high temperature and high humidity as in the case of the compound 1.

Next, the behavior of compound 2 when used in a toner was investigated. The experimental method is the same as that of Example 1 except that the compound 2 (2 parts by weight) is mixed with the compound 1 (2 parts by weight) which is mixed when the resin fine powder is prepared. When the developer thus prepared was tested in the same copying machine as in Example 1, the image was clear even after copying 10,000 sheets.

When this developer was left in an atmosphere of a temperature of 30 ° C. and a humidity of 80% for 100 hours and then tested by the same copying machine, the image was clear even after copying 10,000 sheets.

From the above, it was confirmed that a fine powder of a resin containing Compound 2 can also be used as a toner for electrophotography.

When the bulk compound 2 was allowed to stand at room temperature, it did not discolor after 100 hours and remained a pale yellow color. Therefore, 100 in an atmosphere with a temperature of 30 ° C and a humidity of 80%.
It was left for a while, but it remained pale yellow. In addition, the increase in weight under the above atmosphere was within 3%, and no deliquescent due to moisture absorption was observed. From this, it was confirmed that the compound 2 was also a compound having excellent environmental stability.

(Example 3) Among the charge control agents of the present invention,
The structure shows a method for synthesizing a compound in which X is an N (CH ₃ ) ₂ group, Y is hydrogen, M is Fe, and n is 3 in the above chemical structure (hereinafter referred to as compound 3).

1 part by weight of sodium hydroxide was dissolved in 30 parts by weight of water. After adding 4 parts by weight of 2-dimethylaminobenzoic acid thereto, the mixture was thoroughly stirred and completely dissolved. To this, a solution prepared by dissolving 2 parts by weight of ferric chloride hexahydrate in 20 parts by weight of water was added dropwise. The precipitated solid was collected by filtration and then ethyl acetate-n
About 2 crystals of compound 3 by recrystallization from hexane
Parts by weight were obtained (yield about 50%). It was confirmed by elemental analysis that this solid was the target compound 3. The compound was a brown crystal, but when it was mixed with or dissolved in a toner resin such as styrene-acrylic or polyester, the resin became slightly yellowish. However, no yellowing was observed in the image formed by producing a toner using Compound 3 by the method described below.

Next, the behavior of the compound 3 was examined using a surface charge amount measuring device (TV-100VH manufactured by Toshiba Chemical).
The measuring method is the same as that of Example 1 except that the compound soluble in the tetrahydrofuran solution at the time of sample preparation is compound 3 (1 part by weight) instead of compound 1 (1 part by weight). When the charge amount of the created sample was measured, it was -4 pC /
It was sec. This sample temperature 30 ℃, humidity 80%
The amount of charge after standing for 100 hours in the atmosphere was measured and found to be -4 pC / sec.

From the above, it was found that the resin using the compound 3 was negatively charged, and the charge amount was stable under the high temperature and high humidity as in the case of the compound 1.

Next, the behavior of compound 3 when used in a toner was investigated. The experimental method is the same as that of Example 1 except that the compound 1 (2 parts by weight) which is mixed when the resin fine powder is prepared is the compound 3 (2 parts by weight). When the developer thus prepared was tested in the same copying machine as in Example 1, the image was clear even after copying 10,000 sheets.

When this developer was left in an atmosphere of a temperature of 30 ° C. and a humidity of 80% for 100 hours and then tested by the same copying machine, the image was clear even after copying 10,000 sheets.

From the above, it was confirmed that a fine powder of a resin containing the compound 3 can be used as an electrophotographic toner.

When the bulk compound 3 was left at room temperature, it did not discolor after 100 hours and remained brown. Then, it was left for 100 hours in an atmosphere of a temperature of 30 ° C. and a humidity of 80%, but it remained brown. In addition, the increase in weight under the above atmosphere was within 3%, and no deliquescent due to moisture absorption was observed. From this, it was confirmed that the compound 3 was also a compound excellent in environmental stability.

Example 4 Among the charge control agents of the present invention,
X is an N ((CH ₂ ) ₇ CH ₃ ) ₂ group whose chemical structure is the above chemical structure,
A method for synthesizing a compound in which Y is hydrogen, M is Sn, and n is 4 (hereinafter referred to as compound 4) is shown.

1 part by weight of sodium hydroxide was dissolved in 60 parts by weight of water. To this was added 9 parts by weight of 2-dioctylaminobenzoic acid, and the mixture was thoroughly stirred and completely dissolved. In addition to this, nickel chloride hydrate (water is about 4.
(5 molecules adsorbed) 2 parts by weight dissolved in 20 parts by weight of water were added dropwise. The precipitated solid was collected by filtration and recrystallized from ethyl acetate-n-hexane to obtain about 3 parts by weight of a crystal of compound 4 (yield: about 35%). It was confirmed by elemental analysis that this solid was the target compound 4.
The compound was a yellow crystal, but when mixed with or dissolved in a toner resin such as styrene-acryl or polyester, the resin became slightly yellowish. However, no yellowing was observed in the image formed by producing a toner using Compound 3 by the method described below.

Next, the behavior of the compound 4 was investigated using a surface charge amount measuring device (TV-100VH manufactured by Toshiba Chemical).
The measuring method is the same as that of Example 1 except that the compound dissolved in the tetrahydrofuran solution at the time of sample preparation is compound 4 (1 part by weight) instead of compound 1 (1 part by weight). When the charge amount of the created sample was measured, it was -4.4p.
It was C / sec. This sample has a temperature of 30 ° C and a humidity of 8
When the charge amount after standing for 100 hours in a 0% atmosphere was measured, it was -4 pC / sec.

From the above, it was found that the resin using the compound 4 was negatively charged, and the charge amount was stable under the high temperature and high humidity as in the case of the compound 1.

Next, the behavior of compound 4 when used in a toner was examined. The experimental method is the same as that of Example 1 except that the compound 1 (2 parts by weight) to be mixed when the resin fine powder is prepared is the compound 4 (2 parts by weight). When the developer thus prepared was tested in the same copying machine as in Example 1, the image was clear even after copying 10,000 sheets.

When this developer was left in an atmosphere of a temperature of 30 ° C. and a humidity of 80% for 100 hours and then tested with the same copying machine, the image was clear even after copying 10,000 sheets.

From the above, it was confirmed that a fine powder of a resin containing compound 4 can be used as a toner for electrophotography.

When the bulk Compound 4 was left at room temperature, it did not discolor after 100 hours and remained yellow. Therefore, it was left in an atmosphere of a temperature of 30 ° C. and a humidity of 80% for 100 hours, but it remained yellow. In addition, the increase in weight under the above atmosphere was within 3%, and no deliquescent due to moisture absorption was observed. From this, it was confirmed that the compound 4 was also a compound having excellent environmental stability.

Example 5 Among the charge control agents of the present invention,
X is an N (CH ₂ ) ₁₅ CH ₃ ) ₂ group whose structure is the above chemical structure,
A method for synthesizing a compound in which Y is hydrogen, M is Cu, and n is 2 (hereinafter, referred to as compound 5) will be shown.

1 part by weight of sodium hydroxide was dissolved in 80 parts by weight of water. To this, 15 parts by weight of 2-dihexadecylaminobenzoic acid was added, followed by thorough stirring and complete dissolution. To this was added dropwise 3 parts by weight of copper nitrate trihydrate dissolved in 20 parts by weight of water. After the precipitated solid was collected by filtration, ethyl acetate-
By recrystallizing with n-hexane, about 9 parts by weight of a crystal of compound 5 was obtained (yield: about 60%). It was confirmed by elemental analysis that this solid was the target compound 5. The compound was green crystals, but when mixed with or dissolved in a toner resin such as styrene-acryl or polyester, the resin became slightly green. However, a toner using Compound 5 was produced by the method described below, and an image formed by the toner did not have a green color considered to be due to this influence. Next, a surface charge amount measuring device (Toshiba Chemical TV
The behavior of compound 5 was investigated using −100 VH). The measuring method was to use a compound soluble in the tetrahydrofuran solution at the time of sample preparation instead of compound 1 (1 part by weight).
Same as Example 1 except that (1 part by weight). When the charge amount of the prepared sample was measured, it was -5.6 pC.
It was / sec. This sample has a temperature of 30 ° C and a humidity of 80
%, It was -5.4 pC / sec.

From the above, it was found that the resin containing the compound 5 was negatively charged, and the charge amount was stable under the high temperature and high humidity as in the case of the compound 1.

Next, the behavior of compound 5 when used in a toner was examined. The experimental method is the same as that of Example 1 except that the compound 1 (2 parts by weight) to be mixed when the resin fine powder is prepared is the compound 5 (2 parts by weight). When the developer thus prepared was tested in the same copying machine as in Example 1, the image was clear even after copying 10,000 sheets.

When this developer was left in an atmosphere of a temperature of 30 ° C. and a humidity of 80% for 100 hours and then tested by the same copying machine, the image was clear even after copying 10,000 sheets.

From the above, it was confirmed that a fine powder of a resin containing compound 5 can be used as a toner for electrophotography.

When the bulk compound 5 was allowed to stand at room temperature, it did not discolor after 100 hours and remained green. Therefore, it was left in an atmosphere of a temperature of 30 ° C. and a humidity of 80% for 100 hours, but it remained green. In addition, the increase in weight under the above atmosphere was within 3%, and no deliquescent due to moisture absorption was observed. From this, it was confirmed that the compound 5 was also a compound having excellent environmental stability.

Example 6 Among the charge control agents of the present invention,
The structure is the above chemical structure where X and Y are both CH ₃ groups,
A compound in which M is Zn and n is 2 (hereinafter, compound 6
And)) will be shown.

2 parts by weight of sodium hydroxide was dissolved in 70 parts by weight of water. After 7 parts by weight of 2,3-dimethylbenzoic acid was added to this, it was thoroughly stirred and completely dissolved. A solution prepared by dissolving 3 parts by weight of zinc chloride in 20 parts by weight of water was added dropwise.
The precipitated solid was collected by filtration and recrystallized from ethyl acetate-n-hexane to obtain about 4 parts by weight of a crystal of compound 6 (yield: about 50%). It was confirmed by elemental analysis that this solid was the target compound 6. Compound 6 was a white crystal and did not change the color tone of the resin even when mixed with or dissolved in a toner resin such as styrene-acrylic or polyester.

Next, the behavior of compound 6 was investigated using a surface charge amount measuring device (TV-100VH manufactured by Toshiba Chemical). The measuring method is the same as that of Example 1 except that the compound dissolved in the tetrahydrofuran solution at the time of sample preparation is compound 6 (1 part by weight) instead of compound 1 (1 part by weight). When the charge amount of the created sample was measured,
It was 6.6 pC / sec. This sample at temperature 30
When the charge amount after standing for 100 hours in an atmosphere of temperature and humidity of 80% was measured, it was -6.2 pC / sec.

From the above, it was found that the resin using the compound 6 was negatively charged, and the charge amount was stable under the high temperature and high humidity as in the case of the compound 1.

Next, the behavior of compound 6 when used in toner was examined. The experimental method is the same as that of Example 1 except that the compound 1 (2 parts by weight) to be mixed when the resin fine powder is prepared is the compound 6 (2 parts by weight). When the developer thus prepared was tested in the same copying machine as in Example 1, the image was clear even after copying 10,000 sheets.

When this developer was left in an atmosphere of a temperature of 30 ° C. and a humidity of 80% for 100 hours and then tested by the same copying machine, the image was clear even after copying 10,000 sheets.

From the above, it was confirmed that a fine powder of a resin containing compound 6 can also be used as a toner for electrophotography.

When the bulk Compound 6 was allowed to stand at room temperature, it did not discolor after 100 hours and remained white. Then, it was left for 100 hours in an atmosphere of a temperature of 30 ° C. and a humidity of 80%, but it remained white. In addition, the increase in weight under the above atmosphere was within 3%, and no deliquescent due to moisture absorption was observed. From this, it was confirmed that the compound 6 was also a compound having excellent environmental stability.

Example 7 Among the charge control agents of the present invention,
Both X and Y of the above chemical structure are OCH.
_A method of synthesizing a compound having ₃ groups, M being Zn, and n being 2 (hereinafter referred to as compound 7) will be shown.

2 parts by weight of sodium hydroxide was dissolved in 80 parts by weight of water. After 7 parts by weight of 2,3-dimethoxybenzoic acid was added to this, it was thoroughly stirred and completely dissolved. A solution prepared by dissolving 3 parts by weight of zinc chloride in 20 parts by weight of water was added dropwise. The precipitated solid was collected by filtration and recrystallized from ethyl acetate-n-hexane to obtain about 4 parts by weight of a crystal of compound 7 (yield: about 50%). It was confirmed by elemental analysis that this solid was the target compound 7. Compound 7 was a white crystal and did not change the color tone of the resin even when mixed with or dissolved in a toner resin such as styrene-acrylic or polyester.

Next, the behavior of the compound 6 was examined using a surface charge amount measuring device (TV-100VH manufactured by Toshiba Chemical).
The measurement method is the same as that of Example 1 except that the compound dissolved in the tetrahydrofuran solution at the time of sample preparation is compound 7 (1 part by weight) instead of compound 1 (1 part by weight). When the charge amount of the created sample was measured, it was -4.6p.
It was C / sec. This sample has a temperature of 30 ° C and a humidity of 8
The charge amount after standing for 100 hours in a 0% atmosphere was -4.4 pC / sec.

From the above, it was found that the resin using the compound 7 was negatively charged, and the charge amount was stable under high temperature and high humidity as in the case of the compound 1.

Next, the behavior of compound 7 when used in a toner was examined. The experimental method is the same as that of Example 1 except that the compound 1 (2 parts by weight) mixed with the resin fine powder is used as the compound 7 (2 parts by weight). When the developer thus prepared was tested in the same copying machine as in Example 1, the image was clear even after copying 10,000 sheets.

When this developer was left in an atmosphere of a temperature of 30 ° C. and a humidity of 80% for 100 hours and then tested by the same copying machine, the image was clear even after copying 10,000 sheets.

From the above, it was confirmed that fine powder of resin containing Compound 7 can be used as a toner for electrophotography.

When the bulk Compound 7 was left at room temperature, it did not discolor after 100 hours and remained white. Then, it was left for 100 hours in an atmosphere of a temperature of 30 ° C. and a humidity of 80%, but it remained white. In addition, the increase in weight under the above atmosphere was within 3%, and no deliquescent due to moisture absorption was observed. From this, it was confirmed that the compound 7 was also a compound excellent in environmental stability.

Example 8 Among the charge control agents of the present invention,
In the chemical structure, X is a C ₈ H ₁₇ group, Y is a H group,
A compound in which M is Zn and n is 2
And)) will be shown.

2 parts by weight of sodium hydroxide was dissolved in 80 parts by weight of water. After 12 parts by weight of 2-octylbenzoic acid was added to this, it was thoroughly stirred and completely dissolved. A solution prepared by dissolving 3 parts by weight of zinc chloride in 20 parts by weight of water was added dropwise. The precipitated solid was collected by filtration and recrystallized from ethyl acetate-n-hexane to obtain about 10 parts by weight of a crystal of compound 8 (yield: about 85%). It was confirmed by elemental analysis that this solid was the target compound 8. Compound 8 was a white crystal and did not change the color tone of the resin even when mixed with or dissolved in a toner resin such as styrene-acrylic or polyester.

Next, the behavior of compound 8 was examined using a surface charge amount measuring device (TV-100VH manufactured by Toshiba Chemical). The measuring method is the same as that of Example 1 except that the material that dissolves in the tetrahydrofuran solution at the time of sample preparation is compound 8 (1 part by weight) instead of compound 1 (1 part by weight). When the charge amount of the created sample was measured,
It was 4.8 pC / sec. This sample at 30 ℃
When the charge amount after standing for 100 hours in an atmosphere of 80% humidity was measured, it was -4.2 pC / sec.

From the above, it was found that the resin containing the compound 8 was negatively charged, and the charge amount was stable under high temperature and high humidity as in the case of the compound 1.

Next, the behavior of compound 8 when used in a toner was examined. The experimental method is the same as that of Example 1 except that the compound 1 (2 parts by weight) which is mixed when the resin fine powder is prepared is the compound 8 (2 parts by weight). When the developer thus prepared was tested in the same copying machine as in Example 1, the image was clear even after copying 10,000 sheets.

When this developer was left in an atmosphere of a temperature of 30 ° C. and a humidity of 80% for 100 hours and then tested by the same copying machine, the image was clear even after copying 10,000 sheets.

From the above, it was confirmed that fine powder of a resin containing compound 8 can be used as a toner for electrophotography.

When the bulk Compound 8 was left at room temperature, it did not discolor after 100 hours and remained white. Then, it was left for 100 hours in an atmosphere of a temperature of 30 ° C. and a humidity of 80%, but it remained white. In addition, the increase in weight under the above atmosphere was within 3%, and no deliquescent due to moisture absorption was observed. From this, it was confirmed that the compound 8 was also a compound excellent in environmental stability.

[0087]

By using the charge control agent used in the toner of the present invention, it is possible to provide a toner whose charge amount is not easily influenced by temperature and humidity.

Claims (2)

[Claims] 1. A toner for electrophotography, a compound of at least the following chemical structures (-X is _{-NH 2, -N ((CH 2} ) l
CH _{3) 2} (provided that l is an integer from 0 to 16), - (CH _2)
l' CH ₃ (where l'is an integer from 0 to 16), -O (C
H ₂ ) _{l ″} CH ₃ (where l ″ is an integer from 0 to 16), −
F, -Cl, -Br, -I, -CN, -NO 2 or -OC ₆ H ₅ -Y is _{-H,, - (CH 2)} m CH 3 ( provided that m is an integer from 0 16), - _{CH (CH 3) 2, -C} (CH 3) 3, or -O
_{- (CH 2) m 'CH} 3 ( provided that m' is an integer from 0 16)
M is a metal element, and n is one or more kinds corresponding to the valence of M). [Chemical 1] 2. The electrophotographic toner according to claim 1, wherein M is Zn, Cu, Ni, Fe, Sn, Mn, Ti,
An electrophotographic toner comprising Co, Ga, Ge, or In.