JP3206968B2 - Wet toner and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid toner for developing an electrostatic latent image with a toner dispersed in an insulating liquid and a method for producing the same, and more particularly to a method for producing an olefin resin particle having a carboxyl group or an ester group. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wet toner obtained by depositing particles of a good solvent and a poor solvent in a specific order of solvent replacement, and suitable for electrophotography, electrostatic printing, and information recording, and a method for producing the same.

[0002]

2. Description of the Related Art An electrostatic latent image formed by exposing an electrostatically charged optical semiconductor to light is developed with toner particles made of a coloring material or the like dispersed in an electrically insulating liquid.
An image forming method by an electrophotographic method using a wet toner for transferring an image obtained as necessary is well known. A method of forming an image portion on a lithographic printing plate using an electrophotographic method is widely used in the field of light printing by offset printing. In this method, a lithographic printing plate precursor prepared by applying a photoconductive zinc oxide powder together with a binder resin to a surface of a conductively treated paper is generally charged, the image is exposed to light, the latent image is developed with an electrophotographic toner, and then fixed. Then, a lithographic printing plate is obtained by further performing a hydrophilic treatment on the non-image area.

Conventionally, a liquid toner used as an electrophotographic toner of this type is composed of an electrically insulating liquid and colorant particles having a particle diameter of 0.1 to 1 μm dispersed therein. What dissolves resin for the purpose of dispersion, fixing and charge control of colorant particles is used.

[0004]

This type of wet toner has the advantage that the resolution is excellent due to the small particle size, but the fixing of the toner particles is due to the drying and fixing of the resin dissolved in the solvent, and the printing original plate is used. And the cohesive force of the image portion itself is small, so that the image portion of the printing plate is easily removed during printing, and the printing durability is poor.

The present inventor uses an olefin resin having a carboxyl group or an ester group as a resin, heat-dissolves the resin in a solvent having a high temperature dependency of solubility of the resin to form a resin solution. Is cooled to precipitate resin particles to form a wet toner, whereby resin particles having a narrow particle size distribution can be obtained, and thereby, excellent printing durability, excellent transferability, and good resolution can be obtained. We have found that it is a wet toner, and filed earlier, but there is a need for a wet toner that is made of resin particles having a narrower particle size distribution, and has a uniform density of image deletion and crushing, and a solid surface. It is an object of the present invention to provide a liquid toner in which resin particles are made in sub-micron units and the particle size distribution is narrower, and a good image is obtained, and a method for producing the same.

[0006]

The wet toner of the present invention comprises:
A wet toner obtained by setting the solvent replacement order to a specific order, wherein an olefin resin having a carboxyl group or an ester group (hereinafter, simply referred to as an olefin resin) particles, a colorant, and a hydroxycarboxylic acid ester. In a wet toner comprising a polyhydroxycarboxylic acid ester of 3 to 10 mer as a monomer and a liquid aliphatic hydrocarbon, a liquid aliphatic hydrocarbon which is a poor solvent for the olefin resin and a dispersion medium of the wet toner is added to the liquid aliphatic hydrocarbon. Mixing a good solvent of an olefin-based resin and an olefin-based resin in which a charge control agent is dissolved in a solution in which a polyhydroxycarboxylic acid ester of a 3 to 10-mer having a carboxylic acid ester as a monomer and a colorant are dispersed, This is a wet toner in which particles are precipitated. Further, the liquid toner according to the present invention is characterized in that the liquid aliphatic hydrocarbon used as a dispersion medium for the particle component has a hydroxycarboxylic acid ester as a monomer.
After dispersing the olefin resin particles and a good solvent solution of an olefin resin in which a charge control agent is dissolved in a solvent in which the polyhydroxycarboxylic acid ester of The toner particles are granulated by replacing the good solvent with the poor solvent.

Hereinafter, the present invention will be described in detail.

As the olefin resin, an ethylene-vinyl acetate copolymer is preferred. Examples of the ethylene-vinyl acetate copolymer include Ultracene series manufactured by Tosoh Corporation, for example, 510X, 515F, 530,537,537
L, 537S, 525,520F, 540,540F, 541,541L, 625,630,630F, 68
2,627,631,633,680,681,635,634,710,720,722,725,751,
Sumitate series manufactured by Sumitomo Chemical Co., Ltd., such as 750, 760, for example, DD-10, HA-20, HC-10, HE-10, KA-10, KA-20, KA-3
1, KC-10, KE-10, MB-11, RB-11, etc., Mitsui Dupont Chemical
Evaflex series manufactured by, for example, 45X, YW, 15
0,210,220,250,260,310,360,410,420,450,460,550,560
Nippon Gosei Kogyo Co., Ltd. Soaglen series, for example
Soarex series such as BH, CH, CI, DH, etc., for example, RB
H, RCH, RDH, etc., Takeda Pharmaceutical Co., Ltd. Dumilan series, for example, Dumilan D-219, D-229, D-251S, C-228
0, C-2270, C-1590, C-1570, C-1550 and the like.
Further, Yucalon-Eva manufactured by Mitsubishi Yuka Co., Ltd., Elpacs manufactured by DuPont, USA, and the like can be used.

[0009] In addition, those obtained by modifying a polyolefin resin and introducing a carboxyl group, examples of which are given by trade names are:
N-Polymer manufactured by Nippon Petrochemical Co., Ltd., Tonen Petrochemical Co., Ltd.
Tonen CMP-HA Series, Mitsubishi Yuka MOD
IC, Siixen manufactured by Sumitomo Seimitsu Chemical Industry Co., Ltd., Lombply manufactured by Mitsui Toatsu Chemical Industry Co., Ltd., Mitsui Petrochemical Industry Co., Ltd.
Adomer, etc., and copolymers of ethylene and acrylic acid include Dow Chemical Co., Ltd.
AA copolymer, Mitsubishi Yuka Co., Ltd. Yucalon EAA, Mitsui-DuPont Polychemicals Co., Ltd. Nukullel, Sumitomo Chemical Co., Ltd. Acryft, etc., and a copolymer of ethylene and acrylic acid or methacrylic acid, or Cross-linked so-called ionomers, such as Surlyn manufactured by DuPont in the United States, Himilan manufactured by Dupont Mitsui Polychemicals Co., Ltd., Kobolene latex manufactured by Asahi Kasei Corporation, EVA1 wax of BASF, and ethylene and vinyl acetate Partially saponified copolymers of the following, trade names include copolymers of ethylene and acrylic acid esters, such as Dumilan manufactured by Takeda Pharmaceutical Co., Ltd., and trade names include DPD-6169 manufactured by Nippon Unicar Co., Ltd. And the like, and polyolefin resins containing a carboxyl carbonyl group. These resins may be used as a mixture of at least one or two.

Next, it is preferable to use an aromatic solvent such as tetrahydrofuran (THF) as a solvent for the olefin resin.

The amount of the resin dissolved in the total of the solvent and the resin may be arbitrarily determined. However, if the ratio of the resin is too high, the resin particles may come into contact with each other in the step of depositing the resin particles to form a gel-like mass. Therefore, the content is preferably in the range of 1 to 80% by weight.

Examples of the liquid aliphatic hydrocarbon include n
-Paraffinic hydrocarbons, iso-paraffinic hydrocarbons or mixtures thereof, halogenated aliphatic hydrocarbons and the like. Particularly preferred are branched-chain aliphatic hydrocarbons, and it is preferable to use, for example, Isopar G, Isopar H, Isopar K, Isopar L, Isopar M, Isopar V, etc. manufactured by Exxon. These have little solubility at room temperature in an olefin resin having a carboxyl group or an ester group,
For example, regarding the solubility of the resin in Isopar H, the difference in solubility between 25 ° C. and 65 ° C. is 0.001 g / ml of solvent or less.

Further, the liquid aliphatic hydrocarbon is an electrically insulating liquid and has a volume resistance of 10 ¹⁰ Ω · cm or more,
It is used for the purpose of enhancing the electrical insulation properties of the liquid toner, and it is required that the dissolving power for the liquid toner component is relatively small, thereby preventing deterioration of the liquid toner.

The content of the coloring agent such as carbon black in the resin is 0.0001 to 200% based on the weight of the resin.
Although it can be arbitrarily selected within the range of 0% by weight, in order to reproduce continuous gradation equivalent to offset printing, it is necessary that the optical reflection density after transfer to the transfer target is 0.7 or more. , 1.0 or more. In order to make the optical reflection density 0.7 or more, 10 to 10 on the same weight basis as above.
It becomes 150% by weight. If the ratio exceeds the above range, after development, the optical reflection density of the formed image is reduced, and background contamination is liable to occur.

The coloring agent such as carbon black may be dispersed and dissolved in a solvent after the resin is heated and melted to mix the coloring agent so that the mixing ratio with the resin is a predetermined ratio. The resin and the colorant may be separately dissolved in a solvent or dispersed by ultrasonic dispersion or the like, and then mixed, or the colorant may be dispersed in a resin solution.

Further, as the charge control agent, metal dialkyl sulfosuccinate, manganese naphthenate, calcium naphthenate, zirconium naphthenate, cobalt naphthenate, iron naphthenate, lead naphthenate, nickel naphthenate, chromium naphthenate, zinc naphthenate , Magnesium naphthenate, manganese octylate, calcium octylate, zirconium octylate, iron octylate, lead octylate, cobalt octylate, chromium octylate, zinc octylate, magnesium octylate, manganese dodecylate, calcium dodecylate, dodecyl Zirconium acid,
Metal soaps such as iron dodecylate, lead dodecylate, cobalt dodecylate, nickel dodecylate, chromium dodecylate, zinc dodecylate, magnesium dodecylate, calcium dodecylbenzenesulfonate, sodium dodecylbenzenesulfonate, barium dodecylbenzenesulfonate, etc. , A phospholipid such as lecithin and seharin, and an organic amine such as n-decylamine can be preferably added. In particular, it is desirable to use a transition metal salt of dialkylsulfosuccinic acid (such as cobalt, manganese, zirconium, yttrium, and nickel).
The amount of addition may be the minimum amount that exhibits the charge adjusting effect, but is usually preferably 0.01 to 50% by weight in the electrically insulating liquid.

The charge control agent may be added at any stage in the resin solution, carbon black dispersion, a mixture thereof, the granulation step, and the final wet toner. Is preferred. This has the advantage that usable charge control agents are not limited by the electrically insulating liquid. That is, since the charge control agent significantly lowers the electric resistance of the electrically insulating liquid, it is desirable that the amount of the charge control agent in the electrically insulating liquid be as small as possible. It is desirable that the concentration of the charge control agent in the insulating liquid is high, and the conditions of both are contradictory. However, by adding the charge control agent to the resin solution and sufficiently adsorbing the toner particles, the amount of the charge control agent in the electrically insulating liquid can be maintained at a sufficiently low value.

Next, the polyhydroxycarboxylic acid ester will be described. The polyhydroxycarboxylic acid ester has a granulation adjusting function since the resin particles obtained when added to the granulation step can have a uniform particle size distribution, and further has an affinity with the resin particles in a wet toner. It has been found that it also has a function as a dispersant because of its properties.

The hydroxycarboxylic acid ester as a raw material for the polymerization is a derivative such as an ester of the formula HO-X-COOH, wherein X is a divalent saturated or unsaturated aliphatic hydrocarbon containing at least 12 carbon atoms. Or a divalent aromatic hydrocarbon containing at least 6 carbon atoms, with at least 4 carbon atoms between the hydroxy and carboxyl groups. Preferred as such hydroxycarboxylic acid derivatives are, for example, hydroxycarboxylic acid alkyl esters such as methyl 12-hydroxystearate and ethyl 12-hydroxystearate, lithium 12-hydroxycarboxylate,
Metal salts of hydroxycarboxylic acids such as aluminum hydroxycarboxylate; hydroxycarboxylic acid amides; hydrogenated castor oil and the like.

The polyhydroxycarboxylic acid ester is obtained by polymerizing a hydroxycarboxylic acid ester by partial saponification in the presence of a small amount of an amine or a catalyst, as a polymerization form, by intermolecular esterification, It also contains various forms such as those obtained by intramolecular esterification. The polyhydroxycarboxylic acid ester in the present invention is preferably a 3- to 10-mer of hydroxycarboxylic acid ester, and is a light gray brown wax-like substance. When the degree of polymerization of the polyhydroxycarboxylic acid ester is smaller than 3 or larger than 10, the polyhydroxycarboxylic acid ester is not compatible with the liquid aliphatic hydrocarbon, and the particle size distribution of the resin particles is expected even when used in the granulation step. I can't get anything. The amount of the polyhydroxycarboxylic acid ester added is not particularly limited, but may be 0.01 to 2 per weight of the resin.
It is used in a proportion of 00% by weight. The polyhydroxycarboxylic acid ester is preferably dispersed in an aliphatic hydrocarbon together with a colorant.

In the granulation step of the present invention, the raw materials such as the resin solution, polyhydroxycarboxylic acid ester, carbon black, and the charge control agent are stirred and mixed and then charged into an electrically insulating liquid composed of a liquid aliphatic hydrocarbon. A good solvent solution of an olefin resin in which an olefin resin and a charge control agent are dissolved, and a dispersion of an aliphatic hydrocarbon which is a poor solvent in the olefin resin in which a polyhydroxycarboxylic acid ester and a colorant are dispersed. It is preferable to granulate by mixing with the liquid. In the granulation step, stirring is not necessary, but it is preferable to improve the dispersion of the precipitated resin particles by a dispersion means such as stirring and / or ultrasonic irradiation. The resin particle process is preferably cooled, and the cooling rate may be rapid cooling using dry ice, liquid nitrogen, or the like, or may be poured into a cooled electric insulating liquid, or allowed to cool naturally. You may. When the resin solution is injected into the electrically insulating liquid, the resin particles are precipitated due to the difference in solubility between the resin solution and the electrically insulating liquid, which is a poor solvent for the resin, at the same time as the precipitation of the resin particles due to the temperature difference of the resin solution. .

In this granulation step, the polyhydroxycarboxylic acid ester is compatible with the electrically insulating liquid and has a strong affinity with the resin particles. It is considered that a product having a narrow particle size distribution can be obtained. That is, the particle size of the resulting particles in the range of 0.1 to 10 [mu] m, and the average particle D ₅₀ that indicates the diameter indicated a single peak at 0.6～0.8Myuemu, has been required in the conventional manner Although ball milling operation and classification of the resin particles are not required, it goes without saying that the resin particles may be further finely pulverized by a pulverizer such as a ball mill, a pin pill or a jet mill as needed.

Next, after granulating the resin particles, the solvent used as a good solvent for the olefin resin contained in the electrically insulating liquid is replaced by a poor solvent. As a method for removing the solvent by separating and washing the precipitated resin particles by means such as standing or centrifugation, the concentration of the electrically insulating liquid may be increased, or a solvent of a highly volatile resin may be used. In this case, it can be easily removed by a natural evaporation method, a method of sending hot air to the liquid surface in a container having a large area, a method of distillation under reduced pressure, or the like. The resin particles in the liquid developer thus obtained are positively or negatively charged. For example, a positively charged one gives a positive image in an electrophotographic photosensitive member used in a negatively charged state, for example, a zinc oxide / resin photosensitive member.

The charge control agent may be added at any stage in the resin solution, the carbon black dispersion, a mixture thereof, the granulation step, and the final wet toner. Is preferred. This has the advantage that usable charge control agents are not limited by the electrically insulating liquid. That is, since the charge control agent significantly lowers the electric resistance of the electrically insulating liquid, it is desirable that the amount of the charge control agent in the electrically insulating liquid be as small as possible. It is desirable that the concentration of the charge control agent in the insulating liquid is high, and the conditions of both are contradictory. However, by adding the charge control agent to the resin solution and sufficiently adsorbing the toner particles, the amount of the charge control agent in the electrically insulating liquid can be maintained at a sufficiently low value.

Further, the wet toner obtained by the present invention includes:
Other additives can be used. For example, various resins soluble in an electrically insulating liquid as a fixing agent, for example, modified or unmodified alkyd resin, ordinary acrylic resin, synthetic rubber, polyalkylene oxide, polyvinyl acetal containing polyvinyl butyral, and vinyl acetate resin can be added. .

The wet toner obtained according to the present invention includes:
Many anionic, cationic, amphoteric, or nonionic surfactants can be added as dispersants. In addition, aliphatic acid salts used as the charge control agent, and synthetic resins used as the fixing agent And the like can be used as a dispersant.

When the wet toner according to the present invention is used for electrophotography, it is of course possible to perform a normal transfer method, that is, electric field transfer such as corona transfer, on an insulating transfer object such as paper. However, it can be efficiently transferred from the electrophotographic photosensitive member surface to a conductive transfer target such as a metal by a pressure transfer method. Further, by transferring the toner of the present invention to a substrate for a lithographic printing plate, an image portion having high printing durability can be formed on the lithographic printing plate. This is thought to be due to the presence of the carbonyl group in the carboxyl group or ester group contained in the resin particles in the toner, thereby improving the adhesiveness to paper, plastics, metal, and the like, and also brought about by the presence of the resin particles. It is considered that appropriate flexibility absorbs the impact during printing.

[0028]

According to the present invention, in a granulation step in which a resin solution dissolved in a good solvent is poured into an electrically insulating liquid as a poor solvent and cooled to precipitate resin particles, a hydroxycarboxylic acid ester is used as a monomer. A 10-mer polyhydroxycarboxylic acid ester is present together with a colorant in a poor solvent. The polyhydroxycarboxylic acid ester has compatibility with the electrically insulating liquid, affinity with the resin particles, and has a granulation adjusting function, but the polyhydroxycarboxylic acid ester is dispersed in the colorant dispersion. Adsorption can be made highly by mixing, and the particle size of the resin particles precipitated by mixing with the resin solution dissolved together with the charge control agent is in the sub-micron unit, and an extremely narrow particle size distribution can be obtained. Thus, a wet toner can be easily produced without requiring a ball milling operation or the like.

In the obtained wet toner, the polyhydroxycarboxylic acid ester has not only a function of adjusting granulation but also a function of stably dispersing resin particles in an electrically insulating liquid due to affinity with the resin particles. This makes it possible to obtain a toner in which the resin particles are stably maintained in a dispersed state in the wet toner, the wet toner does not deteriorate, and a stable colored image can be formed. Hereinafter, examples of the present invention will be described. The preparation method of the charge control agent used in the examples is as follows. A method for preparing cobalt dialkyl sulfosuccinate. Sodium dialkyl sulfosuccinate (manufactured by Wako Pure Chemical Industries, Ltd.
A solution in which 25 parts by weight of Aerosol OT) is mixed with 100 parts by weight of tetrahydrofuran and dissolved by heating and stirring at 50 ° C., and then 13 parts by weight of cobalt nitrate is dissolved in a mixed solvent consisting of 30 parts by weight of tetrahydrofuran and 5 parts of methanol. Was added and the mixture was heated and stirred at 50 ° C. for 30 minutes to precipitate a white salt. The white salt was removed by filtration, and the light purple filtrate was concentrated using an evaporator to obtain 10.9 parts by weight (yield: 81%) of light red purple solid cobalt dialkylsulfosuccinate. The solubility at 25 ° C. in Isopar G (manufactured by Exxon) is 0.2 g / ml of solvent.

Method for preparing yttrium dialkyl sulfosuccinate. In the above method for preparing cobalt dialkyl sulfosuccinate, the amount of sodium dialkyl sulfosuccinate is 75 parts by weight, and the reaction is carried out using the same amount of yttrium nitrate instead of cobalt nitrate to obtain yttrium dialkyl sulfosuccinate in a yield of 45%. Was. The solubility at 25 ° C. in Isopar G (manufactured by Exxon) is 0.1%.
2 g / ml solvent.

Preparation of Nickel Dialkyl Sulfosuccinate In the above-mentioned method for preparing cobalt dialkylsulfosuccinate, nickel nitrate hexahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) is used in the same amount instead of cobalt nitrate, and the reaction is carried out to obtain nickel dialkylsulfosuccinate at a yield of 82%. Obtained.
Green microcrystals partially precipitated were removed by hot filtration.
The solubility in Isopar G (manufactured by Exxon) at 25 ° C. is 0.1 g / ml of solvent.

[0032]

【Example】

Example 1 EVA (ethylene-vinyl acetate copolymer, DuPont Mitsui Polychemicals, Inc.) was placed in a 200 ml round bottom flask.
3 g of Evaflex 250), 200 mg of cobalt tetra-2-ethylsulfosuccinate as a charge control agent, and 60 ml of tetrahydrofuran as a solvent were mixed.
For 1 hour to dissolve the resin to prepare a resin solution.

On the other hand, in another container, a carbon black pigment MA100 (manufactured by Mitsubishi Kasei Corporation, particle size 22 nm, BE
T method specific surface area 134m ² , DBP oil absorption 100ml /
100 g, pH 3.5) and 2 g of poly-12-hydroxystearic acid methyl ester (manufactured by Ito Oil Co., Ltd., 3
Monomer, acid value 40.8-42.8, saponification value 196.9-1
97.7, a weight average molecular weight of 1200, a hue (Gardner Heliger) of 6 to 7, and a light gray brown wax of 95 mg were mixed in 100 ml of Isopar G (manufactured by Exxon), and the mixture was mixed with an ultrasonic homogenizer for 20 minutes. Dispersed. The dispersion-mixed liquid was put into a resin solution flask at one time, and further stirred and mixed at 70 ° C. for 1 hour to obtain a coating liquid. The temperature of the obtained coating solution was lowered to 60 ° C. while being left at room temperature, and then cooled to 5 ° C., and Isopar G (manufactured by Exxon) 10 was cooled.
0 ml, and resin particles were precipitated using an ultrasonic homogenizer. After granulation, tetrahydrofuran was removed by an evaporator.

When the particle size of the resin particles was analyzed using Microtrac-IISRA type (manufactured by Nikkiso Co., Ltd.), the resin particles had a particle size width of 0.17 to 2.63 μm and an average particle size D ₅₀ of 0.71 μm. Had a sharp and single peak spectral distribution. In FIG. 1, the particle diameter is represented by a logarithm on the horizontal axis, and a histogram representing the frequency and the cumulative particle size distribution are represented by a polygonal line on the vertical axis.

In addition, infrared absorption spectrum measurement was carried out to determine that the polyhydroxycarboxylic acid ester had adhered to the resin particles, that is, quantification of the OH group stretching vibration region of 3800 to 3200 cm ^-1 and 1760 of the carbonyl group in the carboxylic acid ester. It was confirmed by a peak position change of の 1770 cm ⁻¹ .

The wet toner was diluted with Isopar G (manufactured by Exxon), adjusted to a print density of 1%, and used as a developing solution in the following developing step. The developing step is performed by using an electrostatic recording paper (manufactured by DSCan Seiko Electronics Co., Ltd., an electrostatic plotter,
After forming various electrostatic patterns with a surface charge of 150 V to 50 V on EP-4010), development printing was performed by a roller developing machine using the wet toner prepared above. Developing machine speeds were 2.6 m / min and 10 m / min.

In order to evaluate the electrophoretic properties of the toner, a microammeter (Advantech Co., Ltd.) was used.
Made) and HIGH VOLTAGE SOURCE MEASURE UNIT (KEITHLEY
237), two copper plates 40 mm long and 35 mm wide fixed in the cell at 1 cm intervals were used as electrodes, and a developer was filled between the electrodes, and a 1000
V DC was applied. Initial current value and electrophoresis evaluation were performed. The optical reflection density (OD value) of the printed matter was measured using Macbeth RD914 (manufactured by Macbeth Corporation).

The developing characteristic shows a negative polarity and an OD value of 1.
2. The current value after passing electricity for 60 seconds with an initial current value of 1321 nA is 985 nA, the charge amount per toner weight attached to the electrode (Q / m, unit μC / g) is 300, and the initial current value is 60 seconds later. The difference between the current value and the Q / m value is large, and the electrophoretic property of the toner is excellent. Further, with respect to printability, a good printed matter was obtained without image deletion or crushing, and a printed matter having a uniform solid surface was obtained.

Example 2 Same as Example 1 except that 3 g of EVA (ethylene-vinyl acetate copolymer, Evaflex 260 manufactured by Mitsui DuPont Polychemicals) was used in place of the resin of Example 1. To precipitate resin particles.

Further, evaluation as a wet toner was performed in the same manner as in Example 1. The developing characteristic shows a negative polarity and an OD value of 1.3.
6. The current value after passing electricity for 60 seconds at an initial current value of 1661 nA was 705 nA, and the charge amount per toner weight (Q / m, unit μC / g) attached to the electrode was 300 or more, showing good toner physical properties. Further, with respect to printability, a good printed matter was obtained without image deletion or crushing, and a printed matter having a uniform solid surface was obtained.

Example 3 The same as Example 1 except that 3 g of EVA (ethylene-vinyl acetate copolymer, Evaflex 210 manufactured by DuPont-Mitsui Polychemicals) was used in place of the resin of Example 1. To precipitate resin particles.

Further, evaluation as a wet toner was performed in the same manner as in Example 1. The developing characteristic shows a negative polarity and an OD value of 1.5
5. The current value after passing electricity for 60 seconds at an initial current value of 1000 nA is 480 nA, the charge amount per toner weight attached to the electrode (Q / m, unit μC / g) is 500 or more, and the initial current value is 60 seconds. The difference between the post-current value and the Q / m value is large, and the electrophoretic property of the toner is excellent. Further, with respect to printability, a good printed matter was obtained without image deletion or crushing, and a printed matter having a uniform solid surface was obtained.

Example 4 EV which is a resin having a high crystallinity instead of the resin of Example 1
Resin particles were precipitated in the same manner as in Example 1 except that 3 g of A (ethylene-vinyl acetate copolymer, Evaflex 450 manufactured by Du Pont-Mitsui Polychemicals Co., Ltd.) was used.

A particle size analysis of the precipitated resin particles showed that the resin particles had a sharp single-peak spectral distribution having a particle size width of 0.17 to 3.73 μm and an average particle size D ₅₀ of 1.34 μm. Although it has, the particle size distribution depends on the slightly larger one. In FIG. 2, the horizontal axis represents the logarithm on the horizontal axis, and the vertical axis represents the histogram representing the frequency and the cumulative particle size distribution by a polygonal line.

Further, evaluation as a wet toner was performed in the same manner as in Example 1. The developing characteristic shows a negative polarity and an OD value of 1.
3. The current value after passing electricity for 60 seconds at an initial current value of 1063 nA is 905 nA, the charge amount per toner weight attached to the electrode (Q / m, unit μC / g) is 300 or more, and the initial current value is 60 seconds. The difference between the post-current value and the Q / m value is large, and the electrophoretic property of the toner is excellent. Further, with respect to printability, a good printed matter was obtained without image deletion or crushing, and a printed matter having a uniform solid surface was obtained.

Example 5 The procedure of Example 1 was repeated except that the resin of Example 1 was used with high crystallinity EVA (ethylene-vinyl acetate copolymer, Evaflex 460 manufactured by DuPont-Mitsui Polychemicals Co., Ltd.). Similarly, resin particles were precipitated.

Further, evaluation as a wet toner was performed in the same manner as in Example 1. The developing characteristic shows a negative polarity and an OD value of 1.0
6. The current value after passing the current for 60 seconds with the initial current value of 665 nA is 3
The charge amount per toner weight (Q / m, unit μC / g) attached to the electrode is 200 or more, and the difference between the initial current value and the current value after 60 seconds and the Q / m value are large. It has excellent electrophoretic properties. Further, with regard to printability, a good printed matter was obtained without image deletion or crushing, and the solid surface was uniform.

Example 6 Resin particles were precipitated in the same manner as in Example 1 except that 2 g of general-purpose color carbon black # 50 (manufactured by Mitsubishi Kasei) was used in place of the carbon black of Example 1.

Next, the precipitated resin particles were subjected to particle size analysis, and the resin particles were 0.17 to 5.27 μm.
And the average particle diameter D ₅₀ was 1.12 μm, and had a sharp single peak spectral distribution. In FIG. 3, the horizontal axis represents the logarithm of the particle diameter, and the vertical axis represents the histogram representing the frequency and the cumulative particle size distribution by a polygonal line.

Further, evaluation as a wet toner was performed in the same manner as in Example 1. The developing characteristic shows a negative polarity and an OD value of 0.6
6. The current value after passing electricity for 60 seconds with an initial current value of 7291 nA is 4090 nA, the charge amount per toner weight attached to the electrode (Q / m, unit μC / g) is 100, and the initial current value is 60 seconds later. The difference between the current value and the Q / m value is large, and the electrophoretic property of the toner is excellent. Further, with regard to printability, a good printed matter was obtained without image deletion or crushing, and the solid surface was uniform.

Example 7 The procedure of Example 1 was repeated except that 2 g of Sumika GNO-PP (manufactured by Sumitomo Chemical Co., Ltd.), a phthalocyanine cyan pigment, was used in place of the carbon black of Example 1. Resin particles were produced.

A developing solution was prepared from the obtained toner containing the resin particles in the same manner as in Example 1, and the developing characteristics were evaluated in the same manner.

The developing characteristic shows a negative polarity and an OD value of 1.
2. The current value after passing electricity for 60 seconds at an initial current value of 1130 nA was 768 nA, and the charge amount per toner weight attached to the electrode (Q / m, unit μC / g) was 100. Image formation was possible, there was no image deletion, and the solid surface was a uniform printed matter.

Example 8 In place of the carbon black of Example 1, magenta pigment brilliant carmine 6FB (Dainichi Seika KK) was used.
Resin particles were produced in the same manner as in Example 1 except that g was used.

Next, a particle size analysis of the precipitated resin particles revealed that the resin particles had a particle size of 0.24 to 1.69 μm.
And a sharp single peak spectral distribution with an average particle size D ₅₀ of 0.85 μm.

A developing solution was prepared from the obtained toner containing the resin particles in the same manner as in Example 1, and the developing characteristics were evaluated in the same manner.

The developing characteristic shows a negative polarity and an OD value of 1.
4. The current value after passing electricity for 60 seconds at an initial current value of 1026 nA was 625 nA, and the charge amount per toner weight attached to the electrode (Q / m, unit μC / g) was 200. Image formation was possible, and slight image deletion occurred, but the solid surface was a uniform printed matter.

Example 9 Resin particles were produced in the same manner as in Example 1 except that 2 g of a yellow pigment 2400B (Dainichi Seika Co., Ltd.) was used instead of the carbon black of Example 1.

Next, the precipitated resin particles were subjected to particle size analysis, and the resin particles were found to be 0.83 to 11.15 μm.
It had a sharp, single peak spectral distribution with an average particle size D ₅₀ of 0.98 μm with a particle size width of m.

A developing solution was prepared from the obtained wet toner containing the resin particles in the same manner as in Example 1, and the developing characteristics were evaluated in the same manner.

The developing characteristic shows a negative polarity and an OD value of 1.
1. The current value after passing current for 60 seconds at an initial current value of 930 nA is 6
The toner showed a physical property of 68 nA and a charge amount per toner weight attached to the electrode (Q / m, unit μC / g) of 200. Image formation was possible, there was no image deletion, and the solid surface was a uniform printed matter.

Comparative Example 1 EVA (ethylene-vinyl acetate copolymer, DuPont Mitsui Polychemicals, Inc.) was placed in a 200 ml round bottom flask.
3 g of Evaflex 250), 200 mg of cobalt tetra-2-ethylsulfosuccinate as a charge control agent, and 100 ml of Isopar G (manufactured by Exxon) as a solvent, and the mixture was heated and stirred at 70 ° C. for 1 hour to dissolve the resin. Was prepared.

On the other hand, a carbon black pigment #
50 (manufactured by Mitsubishi Kasei Corporation) and poly-12-hydroxystearic acid methyl ester (manufactured by Ito Oil Co., Ltd.)
Trimer, acid value 40.8-42.8, saponification value 196.9-
197.7, weight average molecular weight 1200, hue (Gardner heligue) 6-7, light gray brown wax) 95 mg
Was mixed in 60 ml of tetrahydrofuran, and dispersed for 20 minutes using an ultrasonic homogenizer. The dispersion-mixed liquid was put into a resin solution flask at one time, and further stirred and mixed at 70 ° C. for 1 hour to obtain a coating liquid. The temperature of the obtained coating liquid was lowered to 60 ° C. while being left at room temperature, and then poured into 100 ml of Isopar G (manufactured by Exxon) cooled to 5 ° C., and resin particles were precipitated using an ultrasonic homogenizer. . After granulation, tetrahydrofuran was removed by an evaporator.

The developing step is performed by using an electrostatic recording paper (manufactured by DS Scan Seiko Denshi Co., Ltd., electrostatic plotter, EP-4010).
After forming various electrostatic patterns having a surface charge of 150 V to 50 V on the surface of the toner, the wet toner prepared above was developed and printed by a roller developing machine. Developing machine speeds were 2.6 m / min and 10 m / min.

In order to evaluate the electrophoretic property of the toner, a microammeter (Advantech Co., Ltd.)
Made) and HIGH VOLTAGE SOURCE MEASURE UNIT (KEITHLEY
237), two copper plates 40 mm long and 35 mm wide fixed in the cell at 1 cm intervals were used as electrodes, and a developer was filled between the electrodes, and a 1000
V DC was applied. Initial current value and electrophoresis evaluation were performed. The optical reflection density (OD value) of the printed matter was measured using Macbeth RD914 (manufactured by Macbeth Corporation).

The developing characteristic shows a negative polarity and an OD value of 1.
2. The current value after passing the current for 60 seconds at the initial current value of 920 nA is 7
The charge amount per toner weight (Q / m, unit μC / g) was 85 nA, and was 85. However, the toner particles are porous and clearly different from those of Example 1. Further, with respect to printability, a good printed matter was obtained without image deletion or crushing, and a printed matter having a uniform solid surface was obtained.

Comparative Example 2 Resin particles were precipitated in the same manner as in Example 1 except that poly-12-hydroxystearic acid methyl ester of Example 1 was not used.

Next, the precipitated resin particles were subjected to particle size analysis. The resin particles had a particle size width of 0.17 to 60 μm and a broad particle size distribution with an average particle size D ₅₀ of 7.37 μm. Was. In FIG. 4, the horizontal axis represents the logarithm of the particle size, and the vertical axis represents the histogram representing the frequency and the cumulative particle size distribution by a polygonal line.

Further, evaluation as a wet toner was performed in the same manner as in Example 1. The developing characteristic shows a negative polarity and an OD value of 0.3.
4. The current value after passing current for 60 seconds at an initial current value of 300 nA is 2
The charge amount per toner weight attached to the electrode (Q / m, unit μC / g) was 98 nA, and was 60 nA.

Regarding printability, image deletion occurred, and the solid surface was uneven.

Comparative Example 3 Resin particles were precipitated in the same manner as in Example 1 except that no charge control agent was used, and after granulation, tetrahydrofuran was removed.

This wet toner was diluted with Isopar G (manufactured by Exxon), adjusted to a print density of 1%, and used as a developer to evaluate print characteristics in the same manner as in Example 1.

The developing characteristic shows bipolarity and an OD value of 0.5
2. The current value after passing current for 60 seconds at an initial current value of 21 nA is 5 n.
A, charge amount per toner weight (Q /
m, unit μC / g) was 40. Further, with regard to printability, although image formation was possible, printed images with image deletion and crushing were obtained. The solid surface was a uniform printed matter.

Comparative Example 4 The same procedure as in Example 1 was conducted except that only resin was used in an amount of 3 g of Sumitomo Chemical Co., Ltd. Sumitate DB-10, which is an ethylene-vinyl acetate polymer having a high crystallinity and a high MI value. Resin particles were precipitated depending on the conditions.

Further, evaluation as a wet toner was performed in the same manner as in Example 1. The developing characteristic shows a negative polarity and an OD value of 0.4
1. The current value after passing current for 60 seconds at the initial current value of 750 nA is 6
The charge amount per toner weight attached to the electrode (Q / m, unit μC / g) is 47, the difference between the initial current value and the current value after 60 seconds and the Q / m value are small, The electrophoresis was inferior. Furthermore, regarding printability,
Image deletion occurred, and a printed matter having a non-uniform solid surface was obtained.

Comparative Example 5 An ethylene-vinyl acetate polymer EVA was used as the resin alone.
3 g of (Sumitate MB-11 manufactured by Sumitomo Chemical Co., Ltd.)
Resin particles were precipitated under the same conditions as in Example 1 except that they were used.

Further, evaluation as a wet toner was performed in the same manner as in Example 1. The developing characteristic shows a negative polarity and an OD value of 0.4
0, the current value after passing electricity for 60 seconds at the initial current value of 1300 nA was 1298 nA, and the charge amount per toner weight attached to the electrode (Q / m, unit μC / g) was 102.

Further, with respect to printability, image deletion occurred, and the solid surface was non-uniform.

Comparative Example 6 A resin was partially saponified ethylene-vinyl acetate copolymer (manufactured by Takeda Pharmaceutical Co., Ltd., Dumilan Series C-22).
Example 1 except that the amount was changed to 3 g.
Resin particles were produced under the same conditions as described above.

A developing solution was prepared from the obtained wet toner containing the resin particles in the same manner as in Example 1, and the developing characteristics were evaluated in the same manner. The developing characteristic shows a negative polarity and an OD value of 0.5
4. The current value after passing current for 60 seconds at an initial current value of 410 nA is 2
The charge amount per toner weight attached to the electrode (Q / m, unit μC / g) was 120, and the difference between the initial current value and the current value after 60 seconds and the Q / m value were small. The electrophoresis was also poor. Further, regarding printability, although image formation was possible, image deletion occurred.
Further, the solid surface was an uneven printed matter.

Comparative Example 7 A sodium dialkyl sulfosuccinate (Aerosol OT manufactured by Wako Pure Chemical Industries, Ltd. (metal part N
The metal substituted salt (Ca, Ni, Y) of a)) was used. 2
3 g of EVA (ethylene-vinyl acetate copolymer, Evaflex 250 manufactured by DuPont-Mitsui Polychemicals Co., Ltd.) in a 00 ml round bottom flask, and YO as a charge control agent
T (yttrium hexa-2-ethylsulfosuccinate)
200 mg and 60 ml of tetrahydrofuran as a solvent were mixed and heated and stirred at 70 ° C. for 1 hour in a warm bath to dissolve the resin to prepare a resin solution.

On the other hand, in another container, carbon black pigment 2200B (manufactured by Mitsubishi Kasei Corporation, particle diameter 18 nm, BE
T method specific surface area 210 m ² / g, DBP oil absorption 45 ml
/ 100 g, pH 3.0) and 2 g of poly-12-hydroxystearic acid methyl ester (manufactured by Ito Oil Co., Ltd.)
Trimer, acid value 40.8-42.8, saponification value 196.9-
197.7, weight average molecular weight 1200, hue (Gardner heligue) 6-7, light gray brown wax) 95 mg
Were mixed and dispersed in 100 ml of Isopar G (manufactured by Exxon) using an ultrasonic homogenizer.

Next, resin particles were produced in the same manner as in Example 1.

A developing solution was prepared from the obtained wet toner containing the resin particles in the same manner as in Example 1, and the developing characteristics were evaluated in the same manner. The developing characteristic shows a negative polarity and an OD value of 1.
0, the current value after passing electricity for 60 seconds at an initial current value of 1060 nA was 704 nA, and the charge amount per toner weight attached to the electrode (Q / m, unit μC / g) was 300 or more, indicating good toner physical properties. Image formation was possible, and good printed matter was obtained without image deletion or crushing. Further, the solid surface was a uniform printed matter.

In the case of Ca and Na, the current value after current supply for 60 seconds at almost the same initial current value of 1020 nA is 654 nA, Q
/ M = 270. However, as the image density, those having a high OD value are Co>Y>Ni> Na
The order is as follows. The OD value was 0.9 in the case of Na.

Comparative Example 8 The carbon black of Example 1 was replaced with carbon black pigment M
A7 (manufactured by Mitsubishi Kasei Corporation, particle size: 24 nm, BET specific surface area: 137 m ² / g, DBP oil absorption: 65 ml / 10
Example 1 except that 0 g, pH 3.5) was used.
Resin particles were produced in the same manner as described above.

A developing solution was prepared from the obtained wet toner containing the resin particles in the same manner as in Example 1, and the developing characteristics were evaluated in the same manner.

The developing characteristic shows a negative polarity and an OD value of 0.
5. The current value after passing electricity for 60 seconds at an initial current value of 1410 nA is 1328 nA, the charge amount per toner weight attached to the electrode (Q / m, unit μC / g) is 120, and the initial current value is 60 seconds later. The difference from the current value and the Q / m value were small, and the electrophoretic property of the toner was poor.

Further, with respect to printability, an image could be formed, but image deletion occurred. Further, the solid surface was an uneven printed matter.

Comparative Example 9 The carbon black of Example 1 was replaced with a carbon black pigment Regal 330 (Cabot Corporation, particle size 25 nm, BET
Specific surface area of 94 m ² / g, DBP oil absorption 65 ml / 1
Resin particles were produced in the same manner as in Example 1 except that 2 g of (00 g, pH 2.5) was used.

A developing solution was prepared from the obtained toner containing the resin particles in the same manner as in Example 1, and the developing characteristics were evaluated in the same manner. The development characteristics show a negative polarity, an OD value of 0.5,
The current value after passing current for 60 seconds at the initial current value of 110 nA is 88 n
A, charge amount per toner weight (Q /
m, unit μC / g) was 20, and the difference between the initial current value and the current value after 60 seconds, the Q / m value was small, and the electrophoretic property of the toner was poor. Further, regarding printability, although image formation was possible, image deletion occurred. Further, the solid surface was an uneven printed matter.

Comparative Example 10 The carbon black of Example 1 was replaced with a carbon black pigment Mogar L (Cabot Co., particle size: 24 nm, BET specific surface area: 138 m ² / g, DBP oil absorption: 60 ml / 10
0 g, pH 2.5) except that 2 g was used.
Resin particles were produced in the same manner as described above.

A developing solution was prepared from the obtained wet toner containing the resin particles in the same manner as in Example 1, and the developing characteristics were evaluated in the same manner. The development characteristics show a negative polarity, an OD value of 0.4,
The initial current value is 90 nA and the current value after conducting for 60 seconds is 66 n
A, charge amount per toner weight (Q /
m, unit μC / g) was 70, the difference between the initial current value and the current value after 60 seconds, the Q / m value was small, and the electrophoretic property of the toner was poor. Further, regarding printability, although image formation was possible, image deletion occurred. Further, the solid surface was an uneven printed matter.

Comparative Example 11 The carbon black of Example 1 was replaced with carbon black pigment Microlith Black (Rosin-treated product of Ciba-Geigy Co., Ltd., particle diameter 30 nm, BET specific surface area 105 m ² / g, D
Resin particles were produced in the same manner as in Example 1 except that 2 g of BP oil absorption amount of 35 ml / 100 g, pH 3.5) was used. Next, resin particles were precipitated in the same manner as in Example 1. Particle size analysis of the precipitated resin particles revealed that the resin particles had a wide particle size range of 0.24 to 60.0 μm, an average particle size D ₅₀ of 6.12 μm, and a wide particle size distribution. In FIG. 5, the horizontal axis represents the logarithm of the particle size, and the vertical axis represents the histogram representing the frequency and the cumulative particle size distribution by a polygonal line.

A developing solution was prepared from the obtained wet toner containing the resin particles in the same manner as in Example 1, and the developing characteristics were evaluated in the same manner. The development characteristics show a negative polarity, an OD value of 0.4,
The current value after conducting for 60 seconds at an initial current value of 210 nA is 180
nA, the charge amount per toner weight attached to the electrode (Q
/ M, unit μC / g) is 40, and the initial current value is 60
After a second, the difference from the current value and the Q / m value were small, and the electrophoretic property of the toner was inferior. Further, regarding printability, although image formation was possible, image deletion occurred. Further, the solid surface was an uneven printed matter.

Comparative Example 12 The carbon black of Example 1 was replaced with a carbon black pigment #
2400B (Mitsubishi Kasei Co., Ltd. Particle size 15 nm, BE
T method specific surface area 260m ² / g, DBP oil absorption 45ml
/ 100 g, pH 2.0), except that 2 g of resin particles were used.

A developing solution was prepared from the obtained wet toner containing the resin particles in the same manner as in Example 1, and the developing characteristics were evaluated in the same manner. The developing characteristic shows a negative polarity and an OD value of 1.2.
4. The current value after passing the current for 60 seconds at the initial current value of 510 nA is 3
The charge amount per toner weight attached to the electrode (Q / m, unit μC / g) was 120 nA, the difference between the initial current value and the current value after 60 seconds, and the Q / m value were small. The electrophoresis was also poor. Further, regarding printability, although image formation was possible, image deletion occurred.
Further, the solid surface was a uniform printed matter.

Comparative Example 13 The carbon black of Example 1 was replaced with carbon black pigment # 850 having a low structure (manufactured by Mitsubishi Kasei Co., Ltd., particle diameter 18 nm, BET specific surface area 200 m ² / g, DB
Resin particles were produced in the same manner as in Example 1 except that 2 g of P oil absorption (80 ml / 100 g, pH 8.0) was used.

A developing solution was prepared from the obtained toner containing the resin particles in the same manner as in Example 1, and the developing characteristics were evaluated in the same manner. The development characteristics show a negative polarity, an OD value of 0.4,
The current value after passing current for 60 seconds at the initial current value of 130 nA is 66 n
A, charge amount per toner weight (Q /
m, unit μC / g) is 100, and the initial current value is 60
After a second, the difference from the current value and the Q / m value were small, and the electrophoretic property of the toner was inferior. Further, regarding printability, although image formation was possible, image deletion occurred. Further, the solid surface was an uneven printed matter.

Comparative Example 14 The difference was that 12-hydroxystearic acid methyl ester (monomer) (special grade reagent manufactured by Junsei Chemical Co., Ltd.) was used in place of the poly-12-hydroxystearic acid methyl ester of Example 1. After granulation in the same manner as in Example 1 except for the particle size analysis, a wide distribution of 0.17 to 60 μm was shown. The average particle size D ₅₀ was 5.01 μm. In FIG. 6, the particle size is represented by a logarithm on the horizontal axis, and a histogram representing the frequency and the cumulative particle size distribution are represented by broken lines on the vertical axis. The obtained wet developer was diluted with Isopar G (manufactured by Exxon) to adjust the printing density to 1%. Next, the initial current value was measured and the electrophoretic characteristics were evaluated.

The developing characteristic shows a negative polarity and an OD value of 0.8.
6. The current value after passing electricity for 60 seconds at an initial current value of 1291 nA was 905 nA, and the charge per toner weight attached to the electrode (Q / m, unit μC / g) was about 100. Although image formation was possible, there was image deletion. The solid surface was a uniform printed matter.

Comparative Example 15 The same procedures as in Example 1 were carried out except that poly-12-hydroxystearic acid methyl ester (a mixture of 10 or more monomers) was used instead of poly-12-hydroxystearic acid methyl ester. Similarly, after granulation, particle size analysis showed a wide distribution of 1.7 to 60 μm. The average particle size D ₅₀ was 36.26 μm. In FIG. 7, the particle size is represented by a logarithm on the horizontal axis, and a histogram representing the frequency and the cumulative particle size distribution are represented by a polygonal line on the vertical axis. The obtained wet developer was diluted with Isopar G (manufactured by Exxon) to adjust the printing density to 1%. Next, the initial current value was measured and the electrophoretic characteristics were evaluated.

The developing characteristic shows a negative polarity and an OD value of 0.9.
1. The current value after current supply for 60 seconds at the initial current value of 233 nA is 1.
The toner had physical properties of about 85 nA and a charge amount per toner weight attached to the electrode (Q / m, unit μC / g) of about 55. Although image formation was possible, there was image deletion. The solid surface was a uniform printed matter.

[0104]

According to the present invention, when olefin resin particles having a carboxyl group or an ester group are used as the resin particles in a wet toner, they have excellent pressure transfer properties, have flexibility even at room temperature, and may damage the surface of the photoreceptor during pressure transfer. When the image portion of the lithographic printing plate is used, the image portion itself has appropriate elasticity. In addition, when direct printing is performed, printing can be performed at a constant printing pressure to absorb irregularities due to transition of paper as a printing medium, so that very smooth printed matter can be obtained, and flat printing of resin particles can be obtained. Because of good adhesion to the plate substrate,
There are advantages such as obtaining sufficient printing durability.

Further, according to the present invention, in a granulation step of charging a resin solution using a solvent which is a good solvent for a resin into an electrically insulating liquid and cooling to precipitate resin particles,
3-1 using hydroxycarboxylic acid ester as a monomer
By dispersing the zero-mer polyhydroxycarboxylic acid ester together with the colorant in the electrically insulating liquid and dissolving the charge control agent in the resin solution, each material is highly adsorbed, Subsequent replacement of the resin particles with a good solvent allows the precipitated resin particles to have a sub-micron particle size and a very narrow particle size distribution, and does not require a ball milling operation or the like. It can manufacture toner.

Further, in the obtained wet toner, the polyhydroxycarboxylic acid ester has not only a function of adjusting granulation but also a function of stably dispersing resin particles in an electrically insulating liquid due to affinity with the resin particles. The resin particles are stably maintained in a dispersed state in the wet toner, and become a non-deteriorating wet toner.

[Brief description of the drawings]

FIG. 1 is a view for explaining the particle size distribution of resin particles of Example 1.

FIG. 2 is a view for explaining the particle size distribution of resin particles of Example 4.

FIG. 3 is a diagram illustrating a particle size distribution of resin particles of Example 6.

FIG. 4 is a view for explaining the particle size distribution of resin particles of Comparative Example 2.

FIG. 5 is a diagram illustrating a particle size distribution of resin particles of Comparative Example 11.

FIG. 6 is a view for explaining the particle size distribution of resin particles of Comparative Example 14.

FIG. 7 is a view for explaining the particle size distribution of resin particles of Comparative Example 15.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-59-95544 (JP, A) JP-A-3-130778 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 9/12-9/135

Claims (3)

(57) [Claims] 1. A wet toner comprising olefin resin particles having a carboxyl group or an ester group, a colorant, a polyhydroxycarboxylic acid ester having a hydroxycarboxylic acid ester as a monomer, and a liquid aliphatic hydrocarbon. A liquid aliphatic hydrocarbon which is a poor solvent for an olefin resin in which a 3 to 10-mer polyhydroxycarboxylic acid ester having a monomer as a monomer and a pigment are dispersed, and an olefin resin in which an olefin resin and a charge control agent are dissolved. A liquid toner, which is obtained by mixing and granulating a resin solution of a solvent, wherein the good solvent in the wet toner is replaced by the poor solvent. 2. A transition metal salt of a dialkyl sulfosuccinic acid whose charge control agent is selected from cobalt, manganese, zirconium, yttrium and nickel, metal-containing azo dyes,
The wet toner according to claim 1, wherein the toner is lecithin. 3. A process for producing a liquid toner comprising olefin resin particles having a carboxyl group or an ester group, a colorant, a polyhydroxycarboxylic acid ester having a hydroxycarboxylic acid ester as a monomer, and a liquid aliphatic hydrocarbon. In a solution in which a 3 to 10-mer polyhydroxycarboxylic acid ester having a carboxylic acid ester as a monomer and a pigment are dispersed in a poor solvent of an olefin resin which is a liquid aliphatic hydrocarbon used as a dispersion medium of a particle component, After mixing a solution of a good solvent of the olefin resin in which the olefin resin particles having a carboxyl group or an ester group and a colorant are dissolved, by lowering the temperature of the solution, the toner particles are deposited. Method for producing a wet toner.