JPH05127422A - Electrostatic charge image developing toner - Google Patents

Abstract

PURPOSE:To improve electrification properties of electrostatic charge image developing toner obtained by emulsion dispersing method. CONSTITUTION:In a toner produced by dissolving or dispersing toner component containing at least a binding resin, a colorant and an electric charge controlling agent into a non-water soluble org. solvent to obtain a resin solution containing colorant, by emulsion dispersing this resin solution containing colorant in a water dispersing liquid, and then removing the non-water soluble org. solvent, both soluble material and insoluble material for non-water soluble org. solvent as the electric charge controlling agents are contained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic charge image developing toner. More specifically, the present invention relates to a small particle size electrostatic image developing toner exhibiting high and stable charging characteristics, which is used for developing an electrostatic image in electrophotography, electrostatic recording and electrostatic printing. is there.

[0002]

2. Description of the Related Art An emulsion dispersion method is known as one of the methods for producing resin fine particles. In this method, a resin solution obtained by dissolving a resin in a water-insoluble organic solvent is emulsified and dispersed in an aqueous dispersion to form an emulsion, and heat is applied to the emulsion while continuing stirring to remove the organic solvent. The resin fine particles are obtained by evaporation and removal. According to this emulsification dispersion method, it is possible to obtain polymer fine particles having an average particle size of about 1 to 10 μm by a relatively simple operation with a simplified process, and it is possible to improve the production efficiency as compared with the pulverization method or the suspension polymerization method. At the same time, costs can be reduced. In addition, there are many types of resins that can be used as compared with the suspension polymerization method and the like.

Therefore, by applying such an emulsion dispersion method,
By blending toner components such as colorants, charge control agents, and magnetic powders into the resin solution, electrostatic image development that meets the needs for speeding up, high image quality, and colorization in electrophotographic copying machines and printers It is expected that the toner for use can be obtained relatively easily and inexpensively. For example, JP-A-61-91666 and JP-A-6-61
JP-A-3-25664 discloses a method for producing a toner for developing an electrostatic charge image by applying such an emulsion dispersion method.

However, in the electrostatic image developing toner obtained by such an emulsion dispersion method, the charge control is one of the problems. The above-mentioned JP-A-61-91666.
JP-A-63-916666 and JP-A-63-916666 disclose an example in which only one kind of charge control agent such as a metal complex or dye, which is generally used in toner for controlling the charge of the toner, is added. Has been done. However, various investigations on such charge control agents generally used in toners have revealed that some of them are soluble in the non-water-soluble organic solvent used in the emulsion dispersion method, and some are insoluble in both. It was found that the charging performance of the toner obtained by the emulsification dispersion method varies depending on which is used.

[0005]

Accordingly, it is an object of the present invention to provide an improved electrostatic image developing toner. It is another object of the present invention to provide a toner for developing an electrostatic charge image, which is a toner produced by an emulsion dispersion method and has high and stable charging characteristics. Another object of the present invention is to provide an electrostatic charge image developing toner having a small particle size, which has good charging characteristics and can be produced at a low production cost with high production efficiency by applying an emulsion dispersion method. To do.

[0006]

[Means for Attempting to Solve the Problems]
A toner component containing at least a binder resin, a colorant and a charge control agent is dissolved or dispersed in a non-water-soluble organic solvent to obtain a colorant-containing resin solution, and the colorant-containing resin solution is emulsified and dispersed in an aqueous dispersion. After that, the toner produced by removing the non-water-soluble organic solvent is characterized in that it contains both charge-soluble agents and those which are insoluble in the non-water-soluble organic solvent. This is accomplished with toner for developing electrostatic images.

[0007]

When a toner is manufactured by the emulsion dispersion method, first, a toner component such as a binder resin, a colorant and a charge control agent is dissolved or dispersed in a non-water-soluble organic solvent to prepare a colorant-containing resin solution. At this time, if a charge control agent that is soluble in a water-insoluble organic solvent is used, the charge control agent will be uniformly distributed in the obtained toner fine particles, and the variation in the charging ability between the respective toner fine particles will be reduced. , Dissolving in a non-water-soluble organic solvent causes the orientation of the molecules, which is thought to have a great influence on the charging ability, to deteriorate, resulting in a decrease in the charging ability. When used, the orientation of the molecules is maintained and the toner is reduced in particle size by the emulsification dispersion method, so that the charging ability of the obtained toner fine particles is improved, but the variation of the charging ability among the respective toner fine particles remains. I found a thing.

Based on these findings, a toner was manufactured by an emulsification dispersion method using a combination of a charge control agent soluble in the non-water-soluble organic solvent used and a charge control agent insoluble in the solvent. In the case where both charge control agents are used alone, only the respective advantages as described above are utilized and the drawbacks are canceled out.The obtained toner exhibits the desired charge amount and the charge between the toner fine particles. It was found that the variation in the amount was small, and the present invention was achieved.

Hereinafter, the present invention will be described in more detail based on the embodiments. The toner for developing an electrostatic image of the present invention is obtained by an emulsion dispersion method and has an average particle diameter of 2 to
The toner particles have a particle size of about 15 μm, more preferably about 4 to 10 μm. In the toner fine particles, a charge control agent that is soluble in the non-water-soluble organic solvent used at the time of manufacture and a charge control agent that is insoluble in the toner particles are used. Both agents are included.

Generally, there are various types of charge control agents (CCA) as substances that can give positive or negative charges by triboelectric charging. Examples of the positive charge control agents include Nigrosine Base EX (produced by Orient Chemical Industry Co., Ltd.). ) And the like, quaternary ammonium salt P-51 (manufactured by Orient Chemical Industry Co., Ltd.), Copy Charge PX VP4
35 (manufactured by Hoechst Co., Ltd.), quaternary ammonium salts, alkoxylated amines, alkylamides, molybdic acid chelate pigments, and imidazole compounds such as PLZ1001 (manufactured by Shikoku Kasei Co., Ltd.).
As the negative charge control agent, for example, Bontron S-22
(Manufactured by Orient Chemical Industry Co., Ltd.), Bontron S-34
(Manufactured by Orient Chemical Industry Co., Ltd.), Bontron E-81
(Manufactured by Orient Chemical Industry Co., Ltd.), Bontron E-84
(Orient Chemical Co., Ltd.), Spiron Black T
Metal complexes such as RH (Hodogaya Chemical Co., Ltd.), thioindigo pigments, quaternary ammonium salts such as Copy Charge NX VP434 (Hoechst Co., Ltd.), Bontron E-89 (Orient Chemical Co., Ltd.) Examples thereof include calixarene compounds such as, and fluorine compounds such as magnesium fluoride and carbon fluoride, but are not limited to these. Incidentally, as the metal complex serving as the negative charge control agent, in addition to those shown above, an oxycarboxylic acid metal complex, a dicarboxylic acid metal complex,
Those having various structures such as amino acid metal complex, diketone metal complex, diamine metal complex, azo group-containing benzene-benzene derivative skeleton metal complex, and azo group-containing benzene-naphthalene derivative skeleton metal complex are included.

Here, whether or not it is soluble in the non-water-soluble organic solvent used depends, of course, on the type of the non-water-soluble organic solvent used, and the molecular weight of the charge control agent,
It depends on factors such as crystallinity, the presence or absence of functional groups, and the structure of the basic skeleton. Therefore, in the present invention, depending on the non-water-soluble organic solvent used, those which are soluble in the non-water-soluble organic solvent and those which are insoluble in the above-mentioned various charge control agents are selected. It may be appropriately selected and used in combination.

The solvent used for producing the toner for developing an electrostatic image of the present invention may be any solvent as long as it is insoluble or hardly soluble in water and dissolves the following binder resin used. , For example, toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, methyl isobutyl. Ketones and the like can be used alone or in combination of two or more, and among these, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform and carbon tetrachloride can be used. Usually, it is preferably used.

When the above-mentioned preferred aromatic solvent and halogenated hydrocarbon are used as the water-insoluble organic solvent, the positive charge control agent soluble in this solvent is, for example, nigrosine base EX. Nigrosine dyes and some quaternary ammonium salts such as Copy Charge PX VP435 and some metal complexes such as Spyron Black TRH and Bontron S-34 as negative charge control agents and Copy Charge NX.
There are some quaternary ammonium salts such as VP434. Others are non-soluble charge control agents,
Among the above-exemplified compounds, examples of the positive charge control agent include PLZ1001, quaternary ammonium salt P-51 and the like, and examples of the negative charge control agent include Bontron E-81 and Bontron E-84. ..

The non-dissolvable charge control agent preferably has a particle size of about 10 to 100 mμ in order to obtain a uniform dispersion. When the particle size of the product supplied as a commercial product or the like is also large in the upper limit of the above range, it is desirable to adjust the particle size to an appropriate particle size by using a known method such as a jet mill.

As described above, the toner for developing an electrostatic charge image of the present invention contains both the charge control agent soluble in the non-water-soluble organic solvent used at the time of production and the charge control agent insoluble. However, these are binder resins 1 contained in the toner.
0.1 to 5 parts by weight, more preferably 0.1 to 5 parts by weight of soluble CCA, and insoluble C to 100 parts by weight, respectively.
It is desired that CA is contained in an amount of 0.5 to 5 parts by weight.
That is, if the content of either the soluble CCA or the insoluble CCA is less than 0.1 parts by weight, sufficient charging performance may not be obtained, while the content of either one may be 5 or less.
This is because if the amount is more than the weight part, there is a possibility that a spent may occur during printing and the charge amount may decrease. Furthermore, the ratio (s / i) of the soluble CCA content (s) and the insoluble CCA content (i) is desired to satisfy the following conditions. 0.1 ≦ (s / i) ≦ 1 That is, if (s / i) is less than 0.1, the variation in the charge amount among the toner fine particles becomes large, and there is a possibility that a poorly charged toner is likely to occur. , Meanwhile (s / i)
Is more than 1, there is a possibility that a sufficient toner charge amount may not be obtained.

Further, the binder resin contained in the toner for developing an electrostatic image of the present invention is not limited as long as it is soluble in the water-insoluble organic solvent used and insoluble in water or almost insoluble in water. There is no particular limitation, and a styrene resin, a (meth) acrylic resin, a styrene- (meth) acrylic copolymer resin, an olefin resin, a polyester resin used as a binder resin in a conventional toner,
Polyamide resin, carbonate resin, polyether,
It is possible to use one or more known various resins such as polyvinyl acetate-based resin, polysulfone, epoxy resin, polyurethane resin, and urea resin.

Further, such a binder resin has a glass transition point (Tg) of 50 to 70 ° C. and a number average molecular weight (Mn) of 1,000 to 50,000, preferably 30.
It is desirable that the molecular weight distribution (Mw / Mn) represented by the ratio of Mn to the weight average molecular weight (Mw) is 2 to 60. When Tg is less than 50 ° C, the heat resistance of the obtained toner is lowered, while when Tg is more than 70 ° C, the fixing property of the obtained toner is lowered. Further, when Mn is less than 1000, high temperature offset tends to occur in the obtained toner, while when it exceeds 50,000, low temperature offset tends to occur on the contrary. Furthermore, Mw / Mn is 2
If it is less than 60, the non-offset region may be narrow in the obtained toner, while if it exceeds 60, low temperature offset is likely to occur. When using the toner for oil application and fixing, Mw / M
It is more preferable that n is 2 to 5, and in the case of an oilless fixing toner, Mw / Mn is 20 to 5
It is more desirable to set it to 0.

As the colorant contained in the toner for developing an electrostatic image of the present invention, various organic or inorganic pigments of various colors can be used as shown below. That is, examples of black pigments include carbon black, copper oxide, manganese dioxide, aniline black, activated carbon, non-magnetic ferrite, magnetic ferrite, and magnetite. Examples of yellow pigments include yellow lead, zinc yellow, cadmium yellow, yellow iron oxide, mineral fast yellow, nickel titanium yellow, navel yellow, naphthol yellow S, Hansa yellow G, Hansa yellow 10G, benzidine yellow G, benzidine yellow GR, quinoline. Yellow rake, permanent yellow NCG, tartrazine rake, etc. Examples of orange pigments include red yellow lead, molybdenum orange, permanent orange GTR, pyrazolone orange, vulcan orange, induslen brilliant orange RK, benzidine orange G and induslen brilliant orange GK. Examples of red pigments include red iron oxide, cadmium red, red lead, mercury sulfide, cadmium, permanent red 4R, resole red, pyrazolone red, watching red, calcium salt, lake red C, lake red D, brilliant carmine 6B, eosin lake, Rhodamine Rake B, Alizarin Rake, Brilliant Carmine 3B and the like. Examples of purple pigments include manganese purple, fast violet B, and methyl violet lake. Examples of blue pigments include navy blue, cobalt blue, alkali blue lake, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue partially chlorinated compound, fast sky blue, and indanthrene blue BC. Examples of green pigments include chrome green, chrome oxide, pigment green B, mica light green lake, and final yellow green G.
and so on. White pigments include zinc white, titanium oxide,
There are antimony white and zinc sulfide. Examples of extender pigments include barite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white.
These colorants may be used alone or in combination of two or more, but it is usually desirable to use 1 to 20 parts by weight, more preferably 2 to 15 parts by weight, based on 100 parts by weight of the binder resin component. .. That is, if the amount is more than 20 parts by weight, the fixing property of the toner is deteriorated, while if the amount is less than 1 part by weight, a desired image density may not be obtained.

In the toner for developing an electrostatic image of the present invention, in addition to the binder resin and the pigment as described above, for example, components such as magnetic powder and an anti-offset agent can be blended, if necessary. .. Magnetic powder, magnetite, γ
-Hematite or various ferrites. As an anti-offset agent used for improving the fixing property of the toner, various waxes, particularly low molecular weight polypropylene,
Polyethylene, or polyolefin wax such as oxidized polypropylene or polyethylene is available.

The toner for developing an electrostatic charge image of the present invention contains the above-mentioned toner components, that is, a binder resin, a pigment and a charge control agent (as well as a magnetic powder and an anti-offset agent which can be added as required). The colorant-containing resin solution obtained by dissolving or dispersing in the water-insoluble organic solvent as described above is emulsified and dispersed in an aqueous dispersion to form an O / W type emulsion, and then the liquid of the emulsion. It is produced by removing the water-insoluble organic solvent from the droplet.

In order to dissolve / disperse the toner component in the non-water-soluble organic solvent, a general apparatus such as a ball mill, a sand grinder or an ultrasonic homogenizer can be used.

The solid content concentration in the colorant-containing resin solution is determined by heating an O / W type emulsion obtained by emulsifying and dispersing the colorant-containing resin solution in an aqueous dispersion, and heating the water-insoluble organic solvent from the droplets. It is necessary to set so that the droplets can be easily solidified into fine particles when removing the polymer. Especially, the concentration of the polymer component in this polymer solution is 5 to 50% by weight, more preferably 10 to 40% by weight. It is considered as a degree.

The colorant-containing resin solution thus prepared is then emulsified and dispersed in an aqueous dispersion to form an O / W type emulsion. Specifically, the mixing system of the colorant-containing resin solution and the aqueous dispersion is sufficiently stirred using a stirring device such as a homomixer. The stirring time is preferably 10 minutes or longer. This is because if the stirring time is too short, a sharp particle size distribution cannot be obtained. Since the particle size of each droplet of the colorant-containing resin solution in the emulsion directly influences the size of the finally obtained toner fine particles, the droplet size corresponding to the size of the toner fine particles to be obtained is determined. It must be formed and its particle size distribution well controlled.

The ratio of the volume of the colorant-containing resin solution (V _p ) to the volume of the aqueous dispersion (V _w ) in preparing the O / W type emulsion is V _p / V _w ≤1, and It is desirable that 0.3 ≦ V _p / V _w ≦ 0.7 is preferable. That is, when V _p / V _w > 1, a stable O / W emulsion cannot be formed, and there is a high possibility that a phase transition will occur or a W / O emulsion will be formed. ..

As the aqueous dispersion used for forming the O / W type emulsion, water can be basically used, but it may contain a water-soluble organic solvent to such an extent that the emulsion is not destroyed. For example, water, water / methanol mixed liquid (weight ratio 50/50 to 100/0), water / ethanol mixed liquid (weight ratio 50/50 to 100/0), water / acetone mixed liquid (50/50 to 100/0), A water / methyl ethyl ketone mixed solution (weight ratio (70/30 to 100/0) or the like can be used.

Further, when forming such an O / W emulsion, it is possible to add a dispersion stabilizer or a dispersion stabilization auxiliary agent, if necessary. The dispersion stabilizer is one having a hydrophilic colloid in an aqueous dispersion, and particularly gelatin, gum arabic, agar, a cellulose derivative (for example, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, etc.), a synthetic polymer (polyvinyl alcohol, Polyvinylpyrrolidone, polyacrylamide, polyacrylic acid salt, polymethacrylic acid salt and the like). A surfactant is usually used as a dispersion stabilizer, and a natural surfactant such as saponin, a nonionic surfactant such as alkylene oxide, glycerin, and glycidol, carboxylic acid, sulfonic acid, phosphoric acid, and sulfuric acid ester. Group, an anionic surfactant containing an acidic group such as a phosphoric acid ester group, and the like. In particular, the combination of the dispersion stabilizer and the dispersion stabilization auxiliary agent is preferably a cellulose derivative (methyl cellulose derivative).
And anionic surfactant (sodium dodecylbenzene sulfonate) or polyvinyl alcohol and anionic surfactant.

After forming the O / W type emulsion as described above, the temperature of the entire system is gradually raised to completely remove the non-water-soluble organic solvent in the droplets to form fine toner particles. Alternatively, it is also possible to spray the O / W type emulsion in a dry atmosphere, completely remove the non-water-soluble organic solvent in the droplets, form toner fine particles, and evaporate and remove the aqueous dispersant. .. The dry atmosphere in which the O / W type emulsion is sprayed is a gas obtained by heating air, nitrogen, carbon dioxide gas, combustion gas, etc. from 20 ° C. to 250 ° C., in particular, a temperature higher than the boiling point of the highest boiling point solvent used. Various air streams are commonly used. After the toner fine particles are formed in this manner, the toner for developing an electrostatic image according to the present invention can be obtained with a sharp particle size distribution by further performing steps such as washing, drying and classification as necessary.

[0028]

EXAMPLES The present invention will be described in more detail below with reference to examples.

Example 1

[Table 1] The above material was added to 400 parts by weight of a toluene / methylene chloride mixed solution (weight ratio 1/1) as a solvent, and treated with an ultrasonic homogenizer (output 400 μA) for 10 minutes to dissolve / disperse the above material in the solvent. This was a colorant-containing resin solution. On the other hand, 1 part by weight of hydroxypropylmethylcellulose (Metroze 65SH-50 manufactured by Shin-Etsu Chemical Co., Ltd.) and 1 part by weight of sodium dodecyl sulfate were dissolved in 100 parts by weight of water to obtain a dispersion liquid. While stirring 100 parts by weight of the dispersion liquid with a homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) at 4,000 rpm, 50 parts by weight of the colorant-containing resin solution was added dropwise to obtain an average particle diameter of the liquid droplets. Was about 6 μm. After completion of dropping, the mixture was stirred for 15 minutes at the same rotation speed, and then the obtained emulsion was added to 200 parts by weight of distilled water, the liquid temperature was maintained at 60 ° C., and the liquid was stirred in the liquid at a speed of 500 rpm with a three-one motor. Methylene chloride and toluene were removed by evaporation from the droplets by a drying method. After the methylene chloride and toluene were completely removed, the obtained colored fine particles were washed and dried and classified to obtain a toner having a volume average particle diameter of 6 μm. The obtained toner was measured for the amount of charge and the amount of poorly charged toner by the methods described below. The results are shown in Table 2.

Examples 2 to 4 Toners having a volume average particle size of 6 μm were obtained in the same manner as in Example 1 except that the amounts of nigrosine base EX and P-51 used were changed as shown in Table 2. With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Example 5 Instead of Nigrosine Base EX, Spiron Black TR
H (manufactured by Hodogaya Chemical Co., Ltd., dissolved in methylene chloride / toluene mixed solution), except that P-51 was replaced by Bontron E-81 (manufactured by Orient Chemical Co., not dissolved in methylene chloride / toluene mixed solution) A toner having a volume average particle size of 6 μm was obtained in the same manner as in Example 1. With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Examples 6 to 8 Toners having a volume average particle size of 6 μm were obtained in the same manner as in Example 1 except that the amounts of Spiron Black TRH and Bontron E-81 used were changed as shown in Table 2. With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Example 9 Polyester resin was replaced with styrene-acrylic resin (softening point 1
21 ° C, Tg 65 ° C, Mn = 1100, Mw / Mn = 2
A toner having a volume average particle size of 6 μm was obtained in the same manner as in Example 1 except that the toner was changed to 2.4). With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Example 10 Polyester resin was replaced with epoxy resin (softening point 126 ° C., T
g Toner having a volume average particle size of 6 μm was obtained in the same manner as in Example 2 except that the toner was changed to 65 ° C.). With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Example 11 Polyester resin was replaced with styrene-acrylic resin (softening point 1
21 ° C, Tg 65 ° C, Mn = 2300, Mw / Mn =
A toner having a volume average particle diameter of 6 μm was obtained in the same manner as in Example 3, except that the toner was changed to 8.8). With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Example 12 The charge control agent nigrosine base EX was added in an amount of 0.5 part by weight, and the quaternary ammonium salt P-51 was added in an amount of 0.5.
A toner having a volume average particle diameter of 6 μm was obtained in the same manner as in Example 1 except that the weight part was used. With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Example 13 A volume average particle diameter of 6 μm was obtained in the same manner as in Example 6 except that the charge control agent Spiron Black TRH was added in an amount of 5 parts by weight and the Bontron E-81 was added in an amount of 5 parts by weight. Toner was obtained. With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Comparative Example 1 A toner having a volume average particle size of 6 μm was obtained in the same manner as in Example 3 except that P-51 was not used. With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Comparative Example 2 A toner having a volume average particle size of 6 μm was obtained in the same manner as in Example 3 except that nigrosine base EX was not used. With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Comparative Example 3 A toner having a volume average particle size of 6 μm was obtained in the same manner as in Comparative Example 1 except that the amount of nigrosine base EX used was changed to 5 parts by weight. With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Comparative Example 4 Comparative Example 2 except that the amount of P-51 used was changed to 5 parts by weight.
A toner having a volume average particle size of 6 μm was obtained in the same manner as in (1). With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Comparative Example 5 A toner having a volume average particle size of 6 μm was obtained in the same manner as in Example 7 except that Bontron E-81 was not used. With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Comparative Example 6 A toner having a volume average particle size of 6 μm was obtained in the same manner as in Example 7 except that Spiron Black TRH was not used. With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Comparative Example 7 A toner having a volume average particle size of 6 μm was obtained in the same manner as in Comparative Example 5 except that the amount of Spiron Black TRH used was changed to 5 parts by weight. With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Comparative Example 8 A toner having a volume average particle size of 6 μm was obtained in the same manner as in Comparative Example 6 except that the amount of Bontron E-81 used was changed to 5 parts by weight. With respect to the obtained toner, the amount of charge and the amount of poorly charged toner were measured in the same manner as in Example 1. The results are shown in Table 2.

Evaluation Method 1) Amount of Charge First, 30 g of a developer was prepared by mixing the toners obtained in Examples 1 to 11 and Comparative Examples 1 to 8 at a ratio of 5% by weight with respect to the carrier. After charging in a polyethylene bottle of 50 cc capacity and rotating at 1200 rpm for 10 minutes, the charge amount was measured. 2) Inadequately Charged Toner Amount 3 g of the developer prepared and stirred in the same manner as in the above measurement of the amount of charge is set on a magnet roll having a diameter of 310 mm, and the counter electrode is precisely weighed. A bias voltage of 1 kv is applied to the polarity opposite to the toner polarity, and the magnet roll is rotated at 1000 rpm for 1 minute. After the operation was completed, the counter electrode was precisely weighed, the difference from the initial value was calculated to obtain the amount of separated toner (non-charged toner) attached to the counter electrode, and this non-charged toner amount was expressed as a ratio to the total toner amount.

[0047]

[Table 2]

As is clear from the results shown in Table 2, the toners of Examples 1 to 11 according to the present invention exhibited a sufficient amount of charge and the occurrence of poorly charged toner was extremely small. Comparative Examples 1, 3, 5 and 7 using only the charge control agent soluble in the water-insoluble organic solvent used at the time
In those of Comparative Examples 2, 4, 6 and 8 in which a sufficient charge amount is not obtained, and only the charge control agent which is not soluble in the water-insoluble organic solvent is used, the charge amount can be increased. However, it was not possible to suppress the generation of poorly charged toner.

[0049]

As described above, according to the present invention, a toner component containing at least a binder resin, a colorant and a charge control agent is dissolved or dispersed in a water-insoluble organic solvent to obtain a colorant-containing resin solution. In a toner produced by emulsifying and dispersing a colorant-containing resin solution in an aqueous dispersion and then removing a non-water-soluble organic solvent, a charge control agent that is not soluble in the non-water-soluble organic solvent Since it is a toner for developing electrostatic images, which contains both soluble and soluble ones, even if the particle size is reduced, the occurrence of non-charged toner such as scattered toner and reversely charged toner is extremely small, and the toner is charged. The control agent has good controllability of the charge amount, and a desired sufficient charge amount can be easily provided.

Claims (1)

[Claims] 1. A colorant-containing resin solution is obtained by dissolving or dispersing a toner component containing at least a binder resin, a colorant and a charge control agent in a non-water-soluble organic solvent, and the colorant-containing resin solution is an aqueous dispersion. A toner produced by removing the non-water-soluble organic solvent after emulsifying and dispersing the same in the toner, and includes both a soluble one and a non-soluble one in the non-water-soluble organic solvent as a charge control agent. A toner for developing an electrostatic charge image, which is characterized in that