JP3229647B2 - 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 and a method for producing the same, and more particularly, to a method for dispersing ethylene-vinyl acetate copolymer resin particles having high polymer properties optimal for granulation in an electrically insulating liquid and a polyhydroxycarboxylic acid. The present invention relates to a wet toner obtained by dissolving an acid ester in an electrically insulating liquid and suitable for electrophotography, electrostatic printing, and information recording, and a method for producing the same.

[0002]

2. Description of the Related Art For example, a method of forming an image portion of a lithographic printing plate using an electrophotographic method is well known in the field of light printing. In this method, generally, a zinc oxide master paper prepared by coating a photoconductive zinc oxide powder with a binder resin on the surface of a conductive treated paper is charged, exposed to an image, developed with an electrophotographic toner, and then fixed. And a method of obtaining a lithographic printing plate by further performing a hydrophilic treatment on a 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 of the colorant particles, but the fixation of the toner is due to the dry fixation of the resin dissolved in the solvent, and the fixation with the plate substrate is difficult. Since the adhesiveness is poor and the cohesive force of the image portion itself is small, the image portion of the printing plate is easily removed during printing, and there is a disadvantage that the printing durability is weak.

Further, in a liquid toner in which resin particles are dispersed, hydroxycarboxylic acid is dispersed in the resin particles to improve the physical properties of the toner.
No. 966 is known, but it cannot be said that the toner properties such as image density, image quality, flow, and fog are still sufficient.

[0006]

SUMMARY OF THE INVENTION According to the present invention, resin particles can be formed in submicron units and narrow in particle size distribution without using a pulverizing medium. It is an object of the present invention to provide a wet toner having improved physical properties and to provide a simple method for producing the wet toner.

[0007]

The wet toner of the present invention comprises:
Ethylene-vinyl acetate copolymer resin particles having a melt flow index of 2.5 to 950, or an ethylene-vinyl acetate copolymer having a melt flow index of 2.5 to 950 to which a coloring agent is added.
In a wet toner comprising vinyl acetate copolymer resin particles and a liquid aliphatic hydrocarbon, a polyhydroxycarboxylic acid ester of 3 to 10 mer having a hydroxycarboxylic acid ester as a monomer is added in an amount of 0 to the weight of the ethylene-vinyl acetate copolymer resin. 0.01 to 200% by weight and a negative charge control agent.

First, the components of the liquid toner of the present invention will be described.

Liquid aliphatic hydrocarbons, which are electrically insulating liquids, have a volume resistance of 10 ¹⁰ Ω · cm or more, and are used for the purpose of enhancing the electrical insulation of a liquid toner. In addition, it is required that the dissolving power for a wet toner component is relatively small, thereby preventing deterioration as a wet toner.

Liquid aliphatic hydrocarbons include liquid 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 in ethylene-vinyl acetate copolymer resin. For example, the solubility of resin in Isopar H is less than 0.001 g / ml of solvent at 25 ° C. and 65 ° C. is there. During the preservation of the liquid toner, the liquid aliphatic hydrocarbon may be present in an amount of 0.01 to 8% by weight, preferably 0.1 to 50% by weight, based on the total weight of the liquid toner.
It is preferable to store in a state of being concentrated to the solid component concentration without change over time. The wet toner at the time of development may be diluted with a liquid aliphatic hydrocarbon so as to have a solid content concentration of 0.5 to 2% by weight, so that a preferable printed matter is obtained.

Next, the ethylene-vinyl acetate copolymer resin used in the present invention has a melt flow index (MI,
g / 10 min) value is from 2.5 to 950, preferably from 2.5 to 950.
400 range. The melt flow index is an index indicating the flow characteristics and film forming characteristics of a thermoplastic specified in ASTM D-1238, and generally, the lower the molecular weight of the polymer, the higher the melt flow index. The present invention has found that when resin particles are formed using an ethylene-vinyl acetate copolymer resin, the melt flow index value of the resin affects the image characteristics and the granulation characteristics of a wet toner.

The melt flow index is 2.5 to 95.
When the value is outside the range of 0, image characteristics as a wet toner, for example, fixing property, fogging property and the like are deteriorated. That is, 2.5
If it is less than 3, the resin does not easily undergo thermal melting during the toner fixing step, impairing the film forming characteristics of the toner image, and making it difficult to produce a printed matter having a constant image quality. Also, 95
If it exceeds 0, the solubility, meltability, dispersion stability and the like of the resin will be deteriorated, and problems will occur in the granulation process.

The ratio of the vinyl acetate component in the ethylene-vinyl acetate copolymer resin is 19% by weight to 40% by weight.
Is preferred, but is not particularly limited. Such an ethylene-vinyl acetate copolymer resin can be named by trade name Evaflex 45X (M) manufactured by DuPont-Mitsui Chemicals, Inc.
I = 95, vinyl acetate component amount 46% by weight, hereinafter the same), 40Y-W (65, 41), 150 (30,
33), 210 (400, 28), 220 (15
0, 28), 250 (15, 28), 260 (6,
28), 310 (400, 25), 360 (2, 2)
5), 410 (400, 19), 420 (150,
19), 450 (15, 19), 460 (2.5,
19), 550 (15, 14), 560 (3.5,
14) and the like.

Also, Ultrasen 5 manufactured by Toyo Soda Kogyo Co., Ltd.
10F (2.5, 6), 515F (2.5, 6), 530 (75, 6), 537 (8.5, 6), 53
7L (8.5, 6), 537S (8.5, 6), 5
25 (20, 7), 520F (2, 8), 540
(3, 10), 540F (3, 10), 541
(9, 10), 541F (9, 10), 625 (1
4, 15), 630 (1.5, 15), 630F
(1.8, 15), 682 (150, 15), 62
7 (0.8, 20), 631 (1.5, 20), 6
33 (20, 20), 680 (160, 20), 6
81 (350, 20), 635 (2.4, 25), 634 (4, 26), 710 (18, 28), 72
0 (150, 28), 722 (400, 28), 7
25 (1000, 28), 751 (6, 28), 7
50 (30, 32) and 760 (70, 42).

Sumitomo Chemical Industries Ltd. Sumitate DB-1
0 (70, 10), HA-20 (20, 70), H
C-10 (150, 20) and HE-10 (300, 2
0), KA-20 (3, 25), KA-31 (7,
28), KC-10 (150, 28), KE-10
(300, 28), MB-11 (60, 32), R
B-11 (60, 41) and the like.

Also, Nippon Gosei Kogyo Co., Ltd. Soabren BH
(150-200, 55), CH (50-100, 6)
0), the same CI (50-100, 60), the same DH (40-
50, 70) and the like.

In addition, a Dumilan series manufactured by Takeda Pharmaceutical Co., Ltd., for example, Dumilan D-219 (MI = 170,
D-229 (72), D-251S
(14), C-2280 (93), C-2270
(85), C-1590 (10), C-1570
(20), C-1550 (15), E-222 (6
5), G-222A (75), G-362A
(1) and C-5791 (50). This series is obtained by partially saponifying vinyl acetate and further adding a partial modification such as introduction of a carboxyl group.
As a result of resin analysis by IR or the like, the carbonyl group stretching vibration range of the IR chart was around 1700 cm ^{-1 to} 1800 cm ^-1 and -O
From the ratio near the H-group stretching vibration region of 3200 cm ⁻¹ , the modification ratio is about 30 to 40%.

Next, the polyhydroxycarboxylic acid ester will be described. When the polyhydroxycarboxylic acid ester is present during the resin particle forming step, it has a granulation adjusting function, and resin particles having a uniform particle size distribution can be obtained. In addition, the resin particles have an affinity for their structure and function as a dispersant.

The hydroxycarboxylic acid ester which is a raw material for the polymerization of the polyhydroxycarboxylic acid ester is obtained by converting the carboxylic acid in the hydroxycarboxylic acid represented by the following formula into an alkyl or aralkyl ester, an amidated one, or a metal. It is salted.
Formula HO-X-COOH wherein X is at least 12
A divalent saturated or unsaturated aliphatic hydrocarbon containing at least 4 carbon atoms, or a divalent aromatic hydrocarbon containing at least 6 carbon atoms, and at least 4 There are carbon atoms. Examples of such hydroxycarboxylic acids include ricinoleic acid, 10-hydroxystearic acid, 12-hydroxystearic acid, hydrogenated castor oil fatty acid (12-hydroxystearic acid containing small amounts of stearic acid and palmitic acid). , 16-hydroxyhexadecanoic acid, 15
-Hydroxypentadecanoic acid, 12-hydroxydodecanoic acid, 4-hydroxybenzoic acid, 2-hydroxy-1-
Naphthoic acid, 3-hydroxy-2-naphthoic acid, 1-hydroxy-2-naphthoic acid, 2-hydroxyphenylacetic acid, 3-hydroxyphenylacetic acid, 4-hydroxyphenylacetic acid, and 3- (4-hydroxyphenyl) -propion Acids and the like.

Examples of the hydroxycarboxylic acid derivatives include hydroxycarboxylic alkyl esters such as methyl 12-hydroxystearate and ethyl 12-hydroxystearate, lithium 12-hydroxycarboxylate, aluminum 12-hydroxycarboxylate and the like. And hydroxycarboxylic acid amides, hydrogenated castor oil and the like.

The polyhydroxycarboxylic acid ester is obtained by polymerizing the above hydroxycarboxylic acid ester by partial saponification in the presence of a small amount of amines or a catalyst, and the polymerization form is obtained by intermolecular esterification. And various forms such as those obtained by intramolecular esterification. The degree of polymerization of the polyhydroxycarboxylic acid ester in the present invention is preferably a 3- to 10-mer, and is a light gray brown wax-like substance. If the degree of polymerization is smaller than 3 or larger than 10, it is not compatible with the liquid aliphatic hydrocarbon, and even when used in the granulation step, the particle size distribution of the resin particles is wide, and the expected one is obtained. Absent. The amount of the polyhydroxycarboxylic acid ester to be added is not particularly limited, but is used at a rate of 0.01% by weight to 200% by weight based on the weight of the resin.

Next, a negative charge control agent is added to the liquid toner of the present invention. Examples of such a charge control agent include metal dialkyl sulfosuccinates, metal-containing azo colorants, and lecithin. In particular, as a metal dialkyl sulfosuccinate, a metal salt of a dialkyl sulfosuccinate having 5 to 17 carbon atoms in the alkyl group, and as the metal,
From scandium of atomic number 21 of the periodic table to zinc of the same 30, from yttrium 39 to the cadmium of the same 48, from lanthanum of the same 57 to mercury of the same 80, and actinium of the same 89, it is a transition metal of at least actinium, preferably Metal salts such as cobalt, manganese, zirconium, yttrium and nickel are preferred.

This type of negative charge control agent has a high adsorption capacity for pigments and resin particles, and achieves its purpose with a minimum amount of use if it is compatible with liquid aliphatic hydrocarbons. Can be. The addition amount of the negative charge control agent may be the minimum amount that exhibits the charge control effect, but is usually 0.01% by weight to 50% by weight in the liquid aliphatic hydrocarbon.

Next, as the coloring agent, a known organic or inorganic coloring agent can be used. Examples of the black colorant include inorganic carbon black, triiron tetroxide, and organic cyanine black.

Examples of the yellow colorant include inorganic yellow lead, cadmium yellow, yellow iron oxide, titanium yellow, and ocher. In addition, as an acetoacetic anilide-based monoazo pigment of a hardly soluble metal salt (azo lake), Hansa Yellow G (CINo. Pigment Yellow 1, hereinafter,
Same), Hansa Yellow 10G (pigment Yellow
3), Hansa Yellow RN (pigment Yellow 65),
Hansa Brilliant Yellow 5GX (pigment Yellow
74), Hansa Brilliant Yellow 10GX (pigme
nt Yellow 98), Permanent Yellow FGL (pig
ment Yellow 97), Shimura Lake Fast Yellow 6
G (pigment Yellow 133), Lionol Yellow K
-2R (pigment Yellow 169), and as the anilide disazo acetoacetate pigment, Disazo Yellow G (p
igment Yellow 12), Disazo Yellow GR (pigme
nt Yellow 13), Disazo Yellow 5G (pigment Y
ellow 14), Disazo Yellow 8G (pigment Yello)
w 17), Disazo Yellow R (pigment Yellow 5)
5), permanent yellow HR (pigment Yellow 8)
3). Examples of the condensed azo pigment include Chromophthal Yellow 3G (pigment Yellow 93), Chromophthal Yellow 6G (pigment Yellow 94), and Chromophthal Yellow GR (pigment Yellow 95). Further, benzimidazolone-based monoazo pigments include Hosta Palm Yellow H3G (pigment Yellow 1).
54) Hosta Palm Yellow H4G (pigment Yello
w 151), Hosta Palm Yellow H2G (pigment Y
ellow 120), Hosta Palm Yellow H6G (pigme
nt Yellow 175), Hosta Palm Yellow HLR (p
igment Yellow 156). Further, as the isoindolinone-based pigment, Irgazine Yellow 3RLT
N (pigment Yellow 110), Irgazine Yellow 2
RLT, Irgazine Yellow 2 GLT (pigment Yello
w 109), Fastogen Super Yellow GROH
(Pigment Yellow 137), Fastogen Super Yellow GRO (pigment Yellow 110), and Sandrin Yellow 6GL (pigment Yellow 173).
ment Yellow 24), anthramirimidine (pigment Y
ellow 108), phthaloylamide-type anthraquinone (pigment Yellow 123), heliofast yellow E3R (pigment Yellow 99), azo-based nickel complex pigment (pigment Green 10) as a metal complex pigment, nitroso-based nickel complex pigment (pigment Yellow 153),
Azomethine-based copper complex pigment (pigment Yellow 117),
Further, phthalimidoquinophthalone pigment (pigment Yellow 138), which is a quinophthalone pigment, may be used.

Examples of the magenta coloring agent include inorganic cadmium red, red iron oxide, silver vermilion, lead red and antimony vermilion. As the azo lake-based azo pigments, brilliant carmine 6B (pigment Red 57:
1), Lake Red (pigment Red 53: 1), Permanent Red F5R (pigment Red 48), Risor Red (pigment Red 49), Persian orange (pigme
nt Orange 17), black orange (pigment Orange)
18), Helio Orange TD (pigment Orange 1)
9), Pigment Scarlet (pigment Red 60:
1), Brilliant Scarlet G (pigment 64:
1), Helio Red RMT (pigment Red 51), Bordeaux 10B (pigment Red 63), Helio Bordeaux BL
(Pigment Red 54), and insoluble azo-based (monoazo, disazo-based, condensed azo-based) include para red (pigment Red 1) and lake red 4R (pigme Red).
nt Red3), permanent orange (pigment Orange)
5), permanent red FR2 (pigment Red2),
Permanent Red FRLL (pigment Red 9), Permanent Red FGR (pigment Red 112), Brilliant Carmine BS (pigment Red 114), Permanent Carmin FB (pigment Red 5), P.I. V. Carmin HR (pigment Red 150), permanent carmin FBB (pigment Red 146), Nova Palm Red F3
RK-F5RK (pigment Red 170), Nova Palm Red HFG (pigment Orange 38), Nova Palm Red HF4B (pigment Red 187), Nova Palm Orange HL. HL-70 (pigment Orange 36);
V. Carmin HF4C (pigment Red 185), Hosta Balm Brown HFR (pigment Brown 25), Vulcan orange (pigment Orange 16), pyrazolone orange (pigment Orange 13), pyrazolone red (pi
gment Red 38) and Chromophtal Orange 4R (pigment Orange 3) as a condensed azo pigment.
1), Chromophtal Scarlet R (pigment Red1)
66), Chromophtal Red BR (pigment Red 14)
4).

Further, as an anthraquinone pigment which is a condensed polycyclic pigment, pyranthrone orange (pigment orange) is used.
40), Anthantrone orange (pigment Orange)
168), dianthraquinonyl red (pigment Red1)
77), and thioindigo-based pigments include thioindigo magenta (pigment Violet 38), thioindigo violet (pigment Violet 36), and thioindigo red (pigment Red 88). Perinone-based pigments include perinone orange (pigment Orange 43). And perylene pigments such as perylene red (pigment Red 190) and perylene vermilion (pig)
ment Red123), perylene maroon (pigment Red1)
79), Perylene scarlet (pigment Red14)
9) and perylene red (pigment Red 178), and quinacridone red (p
igment Violet19), quinacridone magenta (pigme)
nt Red 122), quinacridone maroon (pigment Red
206), quinacridone scarlet (pigment Red2
07). In addition, examples of condensed polycyclic pigments include pyrocholine pigments, red fluorbin pigments, and dyeing lake pigments (water-soluble dye + precipitant → lake fixing).

As the cyan colorant, inorganic ultramarine blue,
Navy blue, cobalt blue, cerulean blue, etc., and as the phthalocyanine series, Fast Gemble-BB (pigment Blue 15), Smiton Cyanine.
Blue HB (pigment Blue 15), cyanine blue 5
020 (pigment Blue 15: 1), Sumika Print
Cyanine Blue GN-O (pigment Blue 15), Fast Sky Blue A-612 (pigment Blue 1
7), cyanine green GB (pigment Green 7),
Cyanine green S537-2Y (pigment Green3
6), Sumiton Fast Violet RL (pigment
Violet 23), and indanthrone blue (PB-60P, PB-22, P
B-21, PB-64), methyl violet phosphorous molybdate lake which is a basic dye lake pigment (PV
-3) and the like. In addition, a coloring agent called a processed pigment in which a resin is coated on the surface of the coloring agent can be used in the same manner.

In consideration of the storage stability as a wet toner, or the transparency and color mixing of an image when a color image is formed using the obtained wet toner, among the above-mentioned coloring agents, black-based coloring agents have -It is preferable to use a mixture of benzidine yellow and Hansa yellow for bon black and yellow, brilliant carmine 6B for magenta, and phthalocyanine blue for cyan.

The colorant has a particle size of 30 to 15 in a secondary aggregation state.
It is preferable to use a powder having a particle size of 0 μm, and the amount used is 0.0001 to 2000% by weight based on the weight of the resin.
Can be arbitrarily selected in the range, but in order to reproduce multicolor continuous gradation equivalent to offset printing, it is necessary that the optical reflection density of each color toner after transfer to the transfer receiving member is 0.7 or more And especially for cyan and black,
It is desirable to have the above. To obtain an optical reflection density of 0.7 or more for each color, the weight is 10 to 150% by weight for black and cyan in the same manner as above, 40 to 150% by weight for magenta, and 10 to 150% for yellow.
It may be 100% by weight. If any of the colors exceeds the above range, background stains are likely to occur after development.

The liquid toner of the present invention contains a polar liquid such as toluene, tetrahydrofuran, alcohols such as methanol, ethanol and propanol, and amino alcohols such as 3-pyridylpropanol with respect to the solid component of the liquid toner. 0.05 to 5% by weight. This addition improves the wetting characteristics of the resin particles, improves the dispersibility, and facilitates the adsorption of the resin particles, so that the image quality and the charging characteristics can be improved.

In the wet toner of the present invention, microsilica, fine-particle titanium oxide, alumina or a sol-gel thereof is contained in an amount of 0.01 to 0.01% based on the solid component of the wet toner.
10% by weight may be added, thereby adsorbing excess ions in the wet toner, increasing the stability of toner charging, and improving image characteristics such as flow improvement.

Other fixing agents include, for example, various resins soluble in an electrically insulating liquid, such as a modified or unmodified alkyd resin, ordinary acrylic resin, synthetic rubber, polyalkylene oxide, polyvinyl acetal (including butyral), A vinyl acetate resin or the like can be added.

Further, many anionic, cationic, amphoteric or nonionic surfactants can be added as a dispersant, and the above-mentioned synthetic resin used as a fixing agent can also be used as a dispersant.

Next, the method for producing the wet toner of the present invention will be described. The first method for producing a wet toner according to the present invention comprises mixing an ethylene-vinyl acetate copolymer resin having a melt flow index of 2.5 to 950 with a liquid aliphatic hydrocarbon while heating, and separately adding a colorant. Is mixed in a liquid aliphatic hydrocarbon, the colorant dispersion is added to the resin dispersion, mixed under heating, cooled, and then subjected to a mixing and dispersion process to produce a wet toner. In the production process, a 3- to 10-mer polyhydroxycarboxylic acid ester having a hydroxycarboxylic acid ester as a monomer is used at a ratio of 0.01% by weight to 200% by weight based on the weight of the ethylene-vinyl acetate copolymer resin. And a negative charge controlling agent.

The ethylene-vinyl acetate copolymer resin is charged into a liquid aliphatic hydrocarbon under a heated condition and mixed. The heating condition may be a temperature range sufficient for plasticizing and liquefying the resin and a temperature range in which each component is not decomposed. A general temperature range is 40 ° C to 120 ° C. The ratio of the ethylene-vinyl acetate copolymer resin to the liquid aliphatic hydrocarbon is within a range in which the ethylene-vinyl acetate copolymer resin becomes fluid when mixed and dispersed in the liquid aliphatic hydrocarbon under heating conditions. Good.

In addition to the resin dispersion, a colorant is charged into a liquid aliphatic hydrocarbon and mixed to prepare a colorant dispersion. The colorant may be dispersed in the liquid aliphatic hydrocarbon so as to have a predetermined mixing ratio with respect to the resin.

The prepared colorant dispersion is put into the above resin dispersion at one time, stirred and mixed in a temperature range of 40 ° C. to 120 ° C., and then cooled. Cooling may be rapid cooling using dry ice, liquid nitrogen, etc., or may be introduced into a cooled liquid aliphatic hydrocarbon, or may be allowed to cool naturally,
Cooled to, for example, 5-15 ° C, the resin particles precipitate out of the dispersion during cooling. According to the findings of the present inventors, it has been found that the average particle diameter of the resin particles is affected by the cooling rate, the average particle diameter increases when the cooling rate is low, and the average particle diameter decreases when the cooling rate is high. . Generally, the temperature at which granulation occurs is from about 24 ° C. to about 30 ° C., and the cooling rate is desirably passed through this temperature range as quickly as possible. That is, by increasing the temperature gradient, the average particle size of the obtained resin particles can be reduced. The cooling rate is preferably 20 ° C./min or more.

The mixing and dispersing process performed after cooling is as follows:
Ultrasonic irradiation, high-speed disperser, jet mill, nibbler, ong mill, ball mill, atomizer, etc., can be used to further reduce the resin particles. That is, the particle size of the obtained particles is 0.1 to
In the range of 10 μm and the average particle size is 0.6 to 0.8 μm
Is obtained. If only the colorant is first milled in a separate step, a wet toner having a sharper particle size can be obtained.

The resin particles obtained according to the present invention have a narrow particle size distribution width and a single peak.
Although the detailed reason for this is unknown, it is thought to be due to the function of adjusting the granulation and the function of dispersing the polyhydroxycarboxylic acid ester in the step of granulating the resin particles.

The polyhydroxycarboxylic acid ester is preferably added to the pigment dispersion, but may be added to the resin dispersion. Also, at the stage of mixing the pigment dispersion and the resin dispersion, the dispersion after cooling You may add in a process.

The negative charge controlling agent may be added to the resin dispersion, but may be added to the colorant dispersion or a mixture thereof, or may be added to the mixture after cooling. And may be mixed and dispersed.

Next, a second method for producing the wet toner of the present invention will be described. The second method for producing a wet toner according to the present invention is characterized in that the ethylene-vinyl acetate copolymer resin having a melt flow index of 2.5 to 950 alone or the ethylene-vinyl acetate copolymer having a colorant added and having a melt flow index of 2.5 to 950 is used. The vinyl acetate copolymer resin is heated and dissolved in a solvent having a high temperature dependency in solubility to the resin to form a resin solution. Then, the resin solution is converted into a 3 to 10-mer polymer having a hydroxycarboxylic acid ester as a monomer. A hydroxycarboxylic acid ester is introduced into a liquid aliphatic hydrocarbon in the presence of 0.01% by weight to 200% by weight based on the weight of the ethylene-vinyl acetate copolymer resin and in the presence of a negative charge control agent, followed by cooling. To precipitate resin particles,
It is characterized in that the solvent is replaced with the aliphatic hydrocarbon.

The solvent for the ethylene-vinyl acetate copolymer resin gives a temperature dependency to the solubility, such as dissolving the resin at heating and not dissolving at room temperature, or dissolving at room temperature and insolubilizing by cooling. Any solvent may be used.
The amount may be at least 01 g / ml of solvent, preferably at least 0.05 g / ml of solvent. Examples of such a solvent include tetrahydrofuran, benzene, toluene, xylene, dimethylformamide (DMF), dimethylsulfoxide (DMSO), acetone, and methyl ethyl ketone (MEK). The amount of the resin dissolved in the total of the solvent and the resin may be arbitrary. However, if the resin ratio is too high, the resin particles may come into contact with each other in the step of depositing the resin particles, resulting in a gel-like mass, and
It may be in the range of weight%. The heating condition for dissolving the resin may be a minimum temperature necessary for dissolving the resin, and it is not preferable to heat more than necessary. The heating conditions are the same as in the first manufacturing method. During dissolution, it is preferable to stir according to a usual method.

The colorant has a particle size of 30 to 15 in a secondary aggregation state.
Using a powdery material of 0 μm, the resin and the colorant are mixed at a predetermined mixing ratio, and the resin is heated and melted to mix the colorant, and then may be dispersed and dissolved in a solvent, or 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 powder colorant may be dispersed in the resin solution. If only the colorant is first milled in a separate step, a wet toner having a sharper particle size can be obtained.

The polyhydroxycarboxylic acid ester may be added in the granulation step, but may be added to the resin solution or may be added to the pigment dispersion.

The step of granulating the resin particles in the present invention is carried out by introducing the resin solution into a cooled liquid aliphatic hydrocarbon. When the resin solution is poured into the liquid aliphatic hydrocarbon, it is desirable to improve the dispersion of the precipitated resin particles by a dispersion means such as stirring and / or ultrasonic irradiation. The cooling may be rapid cooling using dry ice, liquid nitrogen, or the like, may be performed by pouring into a cooled electrically insulating liquid, or may be allowed to cool naturally. The cooling conditions are the same as in the first manufacturing method.

When the resin solution is introduced into the liquid aliphatic hydrocarbon, the resin particles precipitate due to the temperature difference of the resin solution, and at the same time, the solubility of the resin particles with the liquid aliphatic hydrocarbon, which is a poor solvent, is increased. Precipitates. Precipitated resin particles having a sub-micron particle size and a narrow particle size distribution are obtained. That is, the particle size of the obtained particles is in the range of 0.1 to 10 μm and the average particle size is 0.1 μm.
Although it shows a single peak of 6 to 0.8 μm and does not particularly require ball milling operation, classification and the like of resin particles required by the conventional method, ultrasonic irradiation, high speed disperser, jet mill, The resin particles can be further made into fine particles by mixing and dispersing them with a nibbler, an ong mill, a ball mill, an atomizer, or the like.

In the present invention, if a polyhydroxycarboxylic acid ester is present in the granulation step, the polyhydroxycarboxylic acid ester dissolves in the liquid aliphatic hydrocarbon and has a strong affinity for the resin particles. It is considered that the particles function to disperse the particles in the liquid aliphatic hydrocarbon together with the granulation adjusting function.

Next, after the resin particles are precipitated, it is desirable to replace the solvent with a liquid aliphatic hydrocarbon. As a method thereof, the precipitated resin particles may be separated by means of standing or centrifugation, washed, and the solvent may be removed to raise the liquid aliphatic hydrocarbon. When the wet toner according to the present invention is used for electrophotography, it is of course possible to perform an ordinary transfer method on an insulating transfer target such as paper, that is, an electric field transfer such as corona transfer, And the like, can be efficiently transferred from an electrophotographic photosensitive member surface to a transfer target having electric conductivity by a pressure transfer method.

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. It is thought that the presence of carbonyl groups in the carboxyl groups and ester groups contained in the resin particles in the toner improves the adhesion to paper, plastics, metals, and the like, and is caused by the presence of the resin particles. It is considered that appropriate flexibility absorbs the impact during printing.

[0052]

By using an ethylene-vinyl acetate copolymer resin having a melt flow index in the range of 2.5 to 950 as the resin particles in the wet toner, the resin can be easily melted during the toner fixing step. A wet toner which has good film forming characteristics of toner images and can produce printed matter having a constant image quality, and has good solubility, melting property, dispersion stability, etc. of resin when granulating resin particles. And can be.

In the production of a liquid toner, the presence of a polyhydroxycarboxylic acid ester in the granulation of the resin particles is not known for the detailed reason.
The polyhydroxycarboxylic acid ester is compatible with the electrically insulating liquid and has an affinity for the resin particles, so that resin particles having a narrow particle size distribution can be granulated, so that a ball milling operation or the like is not required. And it is possible to easily produce a wet toner by a dispersion means such as ultrasonic dispersion. Further, the polyhydroxycarboxylic acid ester also has a function of stably dispersing the resin particles in the electrically insulating liquid due to affinity with the resin particles, and can be an excellent wet toner.

When a negative charge control agent compatible with liquid aliphatic hydrocarbons is used as a charge control agent, the negative charge control agent has a high adsorptivity to resin particles and exhibits excellent negative chargeability.
Also, the amount of use can be minimized. Also,
A higher optical reflection density can be obtained as compared with the case where a negative charge control agent having no compatibility with the liquid aliphatic hydrocarbon is used.

Hereinafter, examples of the present invention will be described. The preparation method of the negative charge control agent used in the examples is as follows. A method for preparing cobalt dialkyl sulfosuccinate. Sodium dialkyl sulfosuccinate (Wako Pure Chemical Industries, Ltd.)
Aerosol OT) 25 parts by weight in tetrahydrofuran 10
0 parts by weight, and dissolved by heating at 50 ° C. while stirring.
A solution dissolved in a mixed solvent consisting of 5 parts by weight of methanol 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.

Preparation of yttrium dialkylsulfosuccinate. In the above method for preparing cobalt dialkylsulfosuccinate, the amount of sodium dialkylsulfosuccinate used may be 7
The reaction was carried out using 5 parts by weight and the same amount of yttrium nitrate instead of cobalt nitrate to obtain yttrium dialkylsulfosuccinate in a yield of 45%. The solubility at 25 ° C. in Isopar G (manufactured by Exxon) is 0.2 g / ml of solvent.
It is.

A method for preparing nickel dialkylsulfosuccinate. 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 at 25 ° C. in Isopar G (manufactured by Exxon) is 0.1%.
1 g / ml solvent.

In the following examples, Examples 1 to 11
Are examples relating to the first method for producing a wet toner of the present invention, and Examples 12 to 16 are examples relating to the second method.

[0059]

Example 1 2.5 g of EVA (ethylene-vinyl acetate copolymer, Mitsui Dupont Chemical Co., Ltd., Evaflex 250, 28% by weight of vinyl acetate component, MI value 150) in a 200 ml round bottom flask, 256 mg of cobalt 2-ethylsulfosuccinate and Isopar-G 1
Then, the mixture was heated and stirred at 150 ° C. for 1 hour in an oil bath.

On the other hand, in another container, Monast
ral blue FBR (metal phthalocyanine pigment, manufactured by ICI)
2.5 g and poly-12-hydroxystearic acid methyl ester [trimer, manufactured by Ito Oil Co., Ltd., acid value 40.8-
42.8, saponification value 196.9-197.7, weight average molecular weight 1200, hue (Gardner-Helige) 6-7,
Light gray brown wax] 20 mg with Isopar-G100
Dispersed in ml.

This pigment dispersion was added at once to the resin dispersion prepared above, and further stirred and mixed at 150 ° C. for 1 hour. Next, the mixture was left at room temperature, cooled to about 70 ° C., poured into 100 ml of Isopar G at 5 ° C., and an ultrasonic homogenizer (manufactured by Nippon Seiki Seisaku-sho, Ltd.
Using US-300T), the mixture was dispersed and mixed to obtain a wet toner.

The particle size of the resin particles was analyzed by using Microtrac-Mark IISRA type (manufactured by Nikkiso Co., Ltd., North & Slop Co.).
It had a sharp, single peak distribution spectrum with a particle size width of 69 μm and an average particle size of 0.72 μm.

This wet toner is diluted with Isopar G,
The printing density was adjusted to 1% and used in the following developing process. The developing characteristic is positively chargeable, and enables development of an electrostatic latent image having a negatively charged pattern. 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. The developing characteristics were bipolar. 2.6 m / mi developer speed
Performed at n and 10.0 m / min. The photometric colorimetric evaluation of the printed matter was performed by Minolta Co., Ltd. "Spectral colorimeter system CM-1000", and the optical reflection density (OD value) was Macbeth RD914.
(Macbeth Co., Ltd.).

In order to evaluate the electrophoretic property of the toner, a microammeter (Advantech Co., Ltd.)
Made) and HIGH VOLTAGE SOUCE MEASURE UNIT (KEITHLEY
237), 1 cm between electrodes, electrode area 2.5
The wet toner was filled between the metal electrode plates of 3 cm, a voltage of 1000 V was applied between both electrodes, the initial current value was measured, the current value was measured after 60 seconds, and the current value per toner weight (Q / m, unit μC / g) was measured.
The larger the difference between the initial current value and the current value after 60 seconds and the Q / m value, the better the electrophoretic property of the toner.

In order to evaluate the developing characteristics and electrophoretic characteristics of the toner, a zeta potential measuring device (MATEC APPLIED
The mobility (m ² / V · sec) was measured using an ultrasonic zeta potential analysis system (trade name: ESA-8000, manufactured by SCIENCES). The higher the mobility value, the better the high-speed development characteristics.

Further, with respect to the printability, the image quality (whether or not there is a crack), the flow (whether or not there is bleeding), and the degree of fog were visually evaluated.

Table 1 below shows the results of each evaluation.

[0068]

Example 2 Poly-12-hydroxystearate ester (trimer) in Example 1 was replaced with poly-12
-Hydroxystearic acid methyl ester [manufactured by Ito Oil Co., Ltd., tetramer, acid value 35.9-37.0, weight average molecular weight 1560, hue (Gardner Heliger) 6-
7, light gray-brown wax] was used in the same manner to prepare a wet toner.

The particle size of the resin particles was analyzed in the same manner as in Example 1. As a result, a sharp single peak distribution spectrum having a particle size width of 0.17 to 5.27 μm and an average particle size of 1.12 μm was obtained. . The developing characteristics are positively chargeable and enable development of an electrostatic latent image having a negatively chargeable pattern. or,
Evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 1.

[0070]

Example 3 Poly-12-hydroxystearate (trimer) in Example 1 was replaced with poly-12
-Hydroxystearic acid methyl ester [manufactured by Ito Oil Co., Ltd., hexamer, acid value 23.2 to 25.7, weight average molecular weight 1890, hue (Gardner-Helige) 5 to 5
6, light gray-brown wax] was used to prepare a wet toner in the same manner.

The particle size of the resin particles was analyzed in the same manner as in Example 1. As a result, the resin particles had a sharp, single-peak distribution spectrum having a particle size width of 0.17 to 6.53 μm and an average particle size of 1.25 μm. . The developing characteristics are positively chargeable and enable development of an electrostatic latent image having a negatively chargeable pattern. or,
Evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 1.

[0072]

Example 4 A wet toner was prepared in the same manner as in Example 1 except that nickel tetra-2-ethylsulfosuccinate was used instead of cobalt tetra-2-ethylsulfosuccinate. The development characteristics were bipolar. Example 1
Similarly, evaluation as a wet toner was performed, and the results are also shown in Table 1.

[0073]

Example 5 A wet toner was prepared in the same manner as in Example 1, except that yttrium tetra-2-ethylsulfosuccinate was used instead of cobalt tetra-2-ethylsulfosuccinate. The development characteristics were bipolar. The evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 1.

[0074]

Example 6 Instead of the resin of Example 1, EVA (ethylene-vinyl acetate copolymer, Mitsui Dupont Chemical Co., Ltd., Evaflex 460, 19% by weight of vinyl acetate component, MI value 2.5) 2 A wet toner was prepared in the same manner except that 0.5 g of EVA1-WAX (ethylene-vinyl acetate copolymer, containing a wax component, BASF, 10% by weight of vinyl acetate component) was used. .

The particle size of the resin particles was analyzed in the same manner as in Example 1. As a result, the resin particles had a sharp, single-peak distribution spectrum having a particle size width of 0.35 to 10.6 μm and an average particle size of 0.73 μm. . The developing characteristics were negatively chargeable. The evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 1.

[0076]

Example 7 In place of the resin of Example 1, EVA (ethylene-vinyl acetate copolymer, Mitsui Dupont Chemical Co., Ltd., Evaflex 410, 19% by weight of vinegar component, MI value 400) was used. Except for the above, a wet toner was prepared in the same manner.

The particle size of the resin particles was analyzed in the same manner as in Example 1. As a result, the resin particles had a sharp single-peak distribution spectrum having a particle size width of 0.12 to 12.6 μm and an average particle size of 0.88 μm. . The developing characteristics were positively chargeable. The evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 1.

[0078]

Example 8 In place of the resin of Example 1, EVA (ethylene-vinyl acetate copolymer, Mitsui Dupont Chemical Co., Ltd., Evaflex 410, a vinegar component of 19% by weight, MI value of 400) was used. Also, a wet toner was prepared in the same manner except that the step of adjusting the resin dispersion and the step of dispersing the mixed liquid before the cooling step were performed under heating conditions of 70 ° C.

The particle size of the resin particles was analyzed in the same manner as in Example 1. As a result, the resin particles had a sharp, single-peak distribution spectrum having a particle size width of 0.12 to 8.9 μm and an average particle size of 0.83 μm. . The developing characteristics were positively chargeable. The evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 1.

[0080]

Example 9 EVA (ethylene-vinyl acetate copolymer, Mitsui Dupont Chemical Co., Ltd., Evaflex 220, 28% by weight of vinyl acetate component, MI value 150) was used in place of the resin of Example 1, Also, a wet toner was prepared in the same manner except that the step of adjusting the resin dispersion and the step of dispersing the mixed liquid before the cooling step were performed under heating conditions of 70 ° C.

The particle size of the resin particles was analyzed in the same manner as in Example 1. As a result, the resin particles had a sharp single-peak distribution spectrum having a particle size width of 0.12 to 15.7 μm and an average particle size of 0.97 μm. . The developing characteristics were positively chargeable. The evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 1.

[0082]

EXAMPLE 10 EVA (ethylene-vinyl acetate copolymer, Sumitomo Chemical Co., Ltd., Sumitate DB-10, 10% by weight of vinyl acetate component, MI value of 7 instead of the resin of Example 1)
A wet toner was prepared in the same manner as in Example 1 except that Step (0) was used and that the mixed liquid dispersion step before the resin dispersion liquid adjustment step and the cooling step was performed under the heating condition of 70 ° C.

The particle size of the resin particles was analyzed in the same manner as in Example 1. As a result, a sharp single-peak distribution spectrum having a particle size width of 0.12 to 12.3 μm and an average particle size of 0.92 μm was obtained. . The developing characteristics were positively chargeable. The evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 1.

[0084]

EXAMPLE 11 EVA (ethylene-vinyl acetate copolymer, Sumitomo Chemical Co., Ltd., Sumitate MB-11, 32% by weight of vinyl acetate component, MI value of 6 instead of the resin of Example 1)
0) was used, and a wet toner was prepared in the same manner except that the step of adjusting the resin dispersion and the step of dispersing the mixed liquid before the cooling step were performed under the heating condition of 70 ° C.

The particle size of the resin particles was analyzed in the same manner as in Example 1. As a result, the resin particles had a sharp, single-peak distribution spectrum having a particle size width of 0.23 to 21.7 μm and an average particle size of 1.58 μm. . The developing characteristics were positively chargeable. The evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 1.

[0086]

Example 12 A partially saponified ethylene-vinyl acetate copolymer (Takeda Pharmaceutical Co., Ltd.) was placed in a 200 ml round bottom flask.
Dumilan 2270, saponification degree 70%, vinyl acetate component 28% by weight, MI value 85) 2.5 g, cobalt diisooctylsulfosuccinate 256 mg, tetrahydrofuran 50 ml
Were mixed and heated and stirred at 60 to 80 ° C. for 1 hour to dissolve the resin, thereby preparing a resin solution.

On the other hand, in another container, Monastral blue FBR
2.5 g of metal phthalocyanine pigment (manufactured by ICI), poly-12-hydroxystearic acid methyl ester [trimer, manufactured by Ito Oil Co., Ltd., acid value 40.8-42.8, saponification value 196.9- 197.7, weight average molecular weight 120
0, Hue (Gardner Helige) 6-7, light gray brown wax] 90 mg, tetrahydrofuran 50 ml,
Ultrasonic homogenizer (Nippon Seiki Seisakusho Co., Ltd., US-3
Using 00T), the mixture was mixed and dispersed in an ice bath for 10 minutes to prepare a pigment dispersion.

The pigment dispersion and the previously prepared resin solution were charged, and an ultrasonic homogenizer was used.
To prepare a coating liquid.

This coating liquid was poured into 100 ml of Isopar G (manufactured by Exxon) cooled to 5 to 10 ° C., and mixed for 0.5 to 1 hour using an ultrasonic homogenizer to precipitate resin particles. .

When the particle size of the resin particles was analyzed in the same manner as in Example 1, the resin particles had a particle size width of 0.17 to 3.0 μm, an average particle size of 0.7 μm, and a sharp single peak distribution spectrum. Had.

Next, a centrifuge (Sakuma Seisakusho Co., Ltd.)
The resin particles were separated using an auto balance method Model 90-4 large capacity multi-column centrifuge), washed with Isopar G, and further dispersed in Isopar G.

The particle size of the resin particles after the solvent replacement was analyzed in the same manner.
It had a sharp, single-peak distribution spectrum with a particle size of m and an average particle size of 0.80 μm.

Further, it was determined by infrared absorption spectroscopy that the polyhydroxycarboxylic acid ester had adhered to the resin particles, that is, the OH group stretching vibration region of 3800 to 3200 cm ^-1 was determined, and the 1760 ~ 17
It was confirmed by a change in the peak position at 70 cm ^-1 . This wet toner was diluted with Isopar G to adjust the print density to 1%, and evaluated as a wet toner as in Example 1. The results are also shown in Table 1. The developing characteristics were negatively chargeable.

[0094]

Example 13 A wet toner was prepared in the same manner as in Example 12 except that the amount of tetrahydrofuran used was changed to 100 ml, and the wet toner was evaluated in the same manner. The results are also shown in Table 1.

[0095]

Example 14 A partially saponified ethylene-vinyl acetate copolymer (Dumilan 2280, manufactured by Takeda Pharmaceutical Co., Ltd., 70% saponification degree, 28% by weight of vinyl acetate, MI value instead of the resin of Example 12) Except that 93) was used, a wet toner was prepared in the same manner.

When the particle size of the resin particles was analyzed in the same manner as in Example 1, the particle size of the resin particles was 0.17 to 3.9 μm.
It had a sharp, single peak distribution spectrum with an average particle size of 0.96 μm.

When the particle size of the resin particles after the solvent replacement was analyzed in the same manner, the resin particles contained 0.21 to 10.
It had a sharp, single-peak distribution spectrum with a particle size width of 8 μm and an average particle size of 1.54 μm. This wet toner was diluted with Isopar G to adjust the print density to 1%, and evaluated as a wet toner as in Example 1. The results are also shown in Table 1.

[0098]

Example 15 A wet toner was prepared in the same manner as in Example 14 except that the used amount of tetrahydrofuran was changed to 100 ml, and the wet toner was similarly evaluated. The results are also shown in Table 1.

[0099]

Example 16 EVA (ethylene-vinyl acetate copolymer, Sumitomo Chemical Co., Ltd., Sumitate DB-10, 10% by weight of vinyl acetate component, MI value of 7 in a 200 ml round bottom flask)
0) 2.5 g, 256 mg of cobalt diisooctylsulfosuccinate and 100 ml of tetrahydrofuran were mixed, and heated and stirred at 70 ° C. for 1 hour in an oil bath to dissolve the resin to prepare a resin solution.

On the other hand, another container, Monastral blue RFR
2.5 g of metal phthalocyanine pigment (manufactured by ICI) and poly-12-hydroxystearic acid methyl ester (3
90 mg in 100 ml of tetrahydrofuran, an ultrasonic homogenizer (US-300, manufactured by Nippon Seiki Seisaku-sho, Ltd.)
Using T), the mixture was dispersed to prepare a pigment dispersion.

This pigment dispersion was put into the previously prepared resin solution at once, and further mixed and dispersed at 70 ° C. for 1 hour using an ultrasonic homogenizer (same as above) to prepare a coating liquid.

This coating liquid was poured into 150 ml of Isopar G (manufactured by Exxon) cooled to 5 to 10 ° C., and mixed for 0.5 to 1 hour using an ultrasonic homogenizer (same as above) to remove the resin particles. Was deposited.

When the particle size of the resin particles was analyzed in the same manner as in Example 1, the resin particles showed a sharp single-peak distribution spectrum having a particle size width of 0.36 to 12.5 μm and an average particle size of 2.13 μm. Had.

Next, a centrifugal separator (Sakuma Seisakusho Co., Ltd.)
The resin particles were separated using an automatic balance method Model 90-4 large-capacity multi-centrifuge, and the resin particles were washed using Isopar G and then dispersed in Isopar G.

When the particle size of the resin particles after the solvent replacement was analyzed in the same manner, the resin particles were 0.36 to 15.7.
It had a sharp, single-peak distribution spectrum with a particle size width of m and an average particle size of 2.83 μm. This wet toner was diluted with Isopar G to adjust the print density to 1%, and evaluated as a wet toner as in Example 1. The results are also shown in Table 1.

After the coating liquid was cooled to about 60 ° C. while being left at room temperature, it was poured into Isopar G (manufactured by Exxon) in the same manner as above, and dispersed and mixed to precipitate resin particles. The result was obtained.

[0107]

Comparative Example 1 The resin in Example 1 was prepared by using an ethylene-vinyl acetate copolymer (EVA Flex 360, manufactured by Du Pont-Mitsui Polychemicals Co., Ltd., having a saponification degree of 0% and a vinyl acetate component of 2
5% by weight, MI value 2.0) to produce a wet toner in the same manner as in Example 1.

When the toner was evaluated as a wet toner in the same manner as in Example 1, the resin coverage of the coloring agent was low, and porous resin particles were obtained. Further, heat melting of the resin component during the toner fixing step hardly occurs. Further, in the case of the natural drying state as in the case of Example 1, there was a problem that the film formation characteristics were poor and a uniform solid image was not obtained with respect to the formation of image quality of printed matter.

Further, a wet toner was prepared in the same manner as in Example 12 except that the resin in Example 12 was replaced with the above resin, and the toner characteristics were evaluated. Some fine insolubles were present. Furthermore, the obtained printed matter has poor toner film-forming properties,
The image quality was rough. For this reason, there is a problem that it is difficult to form a uniform solid with high concentration.

[0110]

Comparative Example 2 The resin in Example 1 was replaced with an ethylene-vinyl acetate copolymer (Ultracene 725, manufactured by Tosoh Corporation, saponification degree 0%, vinyl acetate component 28% by weight, MI value 1000) A wet toner was produced in the same manner as in Example 1.

When the wet toner was evaluated in the same manner as in Example 1, it was found that the wettability of the resin to the colorant was poor, and the ability to maintain and disperse the resin in the isoper was lowered. Was. Further, the printed matter has a problem that a run and a swim (streak) occur.

A wet toner was prepared in the same manner as in Example 12, except that the resin in Example 12 was replaced with the above resin.
As a result of the evaluation, there was a problem in the ability to retain the colorant at the time of granulation similarly to the above, and the resulting toner was not uniformly coated with the pigment. Therefore, there is a problem that a uniform solid image cannot be obtained for forming a printed matter.

[0113]

Comparative Example 3 Poly-12-hydroxystearic acid methyl ester (trimer) in Example 1 was replaced with 12
A wet toner was prepared in the same manner except that hydroxystearic acid (manufactured by Kanto Chemical Co., Ltd.) was used. The developing characteristics were positively chargeable. When the particle size of the resin particles was analyzed in the same manner as in Example 1, the particle size was 0.17 to 60 μm, the average particle size was 7.53 μm, and the particle size was wide. The initial current value was 238 nA (current value after 60 seconds was 134 nA). ) And the electrophoretic force is small, and the solid image formed after corona charging on the electrostatic recording paper has a problem that vignetting is severe, a clean solid image cannot be obtained, and the flow on the electrode plate and the fixing are poor. Was something. Further, evaluation as a wet toner was performed in the same manner as in Example 1, and the results are shown in Table 2.

[0114]

Comparative Example 4 In place of poly-12-hydroxystearic acid methyl ester (trimer) in Example 1, poly-12-hydroxystearic acid methyl ester [manufactured by Ito Oil Co., Ltd .; Average molecular weight 420
0, molecular weight distribution width (= number average molecular weight / weight average molecular weight)
1.63, hue (Gardner-Helige) 5-6, light gray-brown solid], and a wet toner was prepared in the same manner as in Example 1.

When the particle size of the resin particles was analyzed in the same manner as in Example 1, the particle size width was 0.24 to 60 μm, and the average particle size was 8.8.
It has a wide grain size of 7 μm and an initial current value of 150 n.
A (current value 95 nA after 60 seconds) and electrophoretic force are small,
Further, the solid image formed on the electrostatic recording paper after corona charging has a problem that the solid image is severely rough, a clean solid image cannot be obtained, and the flow on the electrode plate and the fixing are poor. The evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 2.

[0116]

Comparative Example 5 A wet toner was prepared in the same manner as in Example 1 except that poly-12-hydroxystearic acid methyl ester (trimer) was omitted.

The particle size of the resin particles was analyzed in the same manner as in Example 1. As a result, the particle size range was 1.69 to 60 μm, and the average particle size was 1.
The particle size was as wide as 3.4 μm, and it was impossible to control the particle size in the submicron range. In addition, the initial current value 180
nA (current value of 110 nA after 60 seconds), the electrophoretic force was small, and the solid image formed after corona charging on the electrostatic recording paper was so rough that a clean solid image could not be obtained and flow on the electrode plate. However, the fixing was poor. The evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 2.

[0118]

Comparative Example 6 A wet toner was prepared in the same manner as in Example 1, except that the negative charge control agent was omitted. The evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 2.

[0119]

Comparative Example 7 In place of poly-12-hydroxystearic acid methyl ester (trimer) in Example 12, 1
A wet toner was prepared in the same manner except that 2-hydroxystearic acid (manufactured by Kanto Chemical Co., Ltd.) was used. When particle size analysis of the resin particles was performed in the same manner as in Example 1, 1.2 to
The particle size width is 60 μm, the average particle size is 8.7 μm, and the particle size width is wide. The initial current value is 115 nA, the current value after 60 seconds is 90 nA, the electrophoretic force is small, and it is formed after corona charging on electrostatic recording paper. The solid image had a problem that the solid image was so rough that a clean solid image could not be obtained, and the flow on the electrode plate and the fixing were poor. Further, evaluation as a wet toner was performed in the same manner as in Example 1, and the results are shown in Table 2.

[0120]

Comparative Example 8 In place of poly-12-hydroxystearic acid methyl ester (trimer) in Example 12, poly-12-hydroxystearic acid methyl ester [manufactured by Ito Oil Co., Ltd .; Average molecular weight 420
0, molecular weight distribution width (= number average molecular weight / weight average molecular weight)
1.63, hue (Gardner-Helige) 5-6, light gray-brown solid], and a wet toner was produced in the same manner.

When the particle size of the resin particles was analyzed in the same manner as in Example 1, the particle size width was 0.36 to 60 μm, and the average particle size was 1
It has a wide particle size range of 5.9 μm and an initial current value of 11
The electrophoretic force was 7 nA, the current value was 86 nA after 60 seconds, and the electrophoretic force was small. Further, the solid image formed after corona charging on the electrostatic recording paper was severely rough, a clean solid image could not be obtained, and flow on the electrode plate, There was a problem that the fixing was poor. The evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 2.

[0122]

Comparative Example 9 A wet toner was prepared in the same manner as in Example 12, except that poly-12-hydroxystearic acid methyl ester (trimer) was omitted.

When the particle size of the resin particles was analyzed in the same manner as in Example 1, the particle size width was 0.36 to 60 μm and the average particle size was 1
It has a wide particle size range of 5.7 μm and an initial current value of 95
nA, the current value is 63 nA after 60 seconds, and the electrophoretic force is small.
Further, the solid image formed on the electrostatic recording paper after corona charging has a problem that the solid image is severely rough, a clean solid image cannot be obtained, and the flow on the electrode plate and the fixing are poor. The evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 2.

[0124]

Comparative Example 10 A wet toner was prepared in the same manner as in Example 12, except that the negative charge control agent was omitted. The evaluation as a wet toner was performed in the same manner as in Example 1. The results are also shown in Table 2.

[0125]

[Table 1]

[0126]

[Table 2]

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-243966 (JP, A) JP-A-62-98365 (JP, A) JP-A-49-17742 (JP, A) 225363 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G03G 9/12-9/13

Claims (3)

(57) [Claims] 1. A melt flow index of 2.5 to 9.
50 of ethylene-vinyl acetate copolymer resin particles or a melt flow index to which a coloring agent is added is 2.5 to 95.
0 ethylene-vinyl acetate copolymer resin particles and liquid aliphatic
In a wet toner comprising a hydrocarbon, a ratio of 0.01 to 200% by weight of a 3 to 10-mer polyhydroxycarboxylic acid ester having a hydroxycarboxylic acid ester as a monomer based on the weight of the ethylene-vinyl acetate copolymer resin is used. And a negative charge controlling agent. 2. A melt flow index of 2.5 to 9.
After mixing the ethylene-vinyl acetate copolymer resin with the liquid aliphatic hydrocarbon under heating, and separately mixing the colorant into the liquid aliphatic hydrocarbon, the colorant dispersion was mixed with the resin. It is added to the dispersion, mixed under heating, and then cooled, and then subjected to a mixing and dispersing step to produce a wet toner. The polyhydroxycarboxylic acid ester of the above-mentioned ethylene-vinyl acetate
0.01 to 200% by weight per copolymer resin weight
A method for producing a liquid toner, wherein the toner is present in a proportion and a negative charge control agent is present. 3. The melt flow index is 2.5-9.
50 ethylene-vinyl acetate copolymer resin alone or a melt flow index to which a coloring agent is added is 2.5 to 95.
After heat-dissolving the ethylene-vinyl acetate copolymer resin in a solvent having high temperature dependency in solubility to the resin to form a resin solution, the resin solution is prepared by using a hydroxycarboxylic acid ester as a monomer. Monomeric polyhydroxycarboxylic acid ester as the ethylene-vinyl acetate
0.01% to 200% by weight per weight of polymerized resin
In a liquid aliphatic hydrocarbon in the presence of the compound and in the presence of a negative charge control agent, cooling and precipitating resin particles, and replacing the solvent with the aliphatic hydrocarbon. Manufacturing method of toner.