JPH11119471A - Toner matrix particles, toner and developer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain toner matrix particles for developing an electrostatic charge image having clear satisfactory color reproducibility and color forming property while solving problems of existing methods when a full-color image is formed using a full-color copying machine or printer and to obtain a toner using the toner matrix particles and a developer. SOLUTION: A mixture of at least an org. pigment (A), a water-soluble inorg. salt (B), a water-soluble solvent (C) and terpene phenol resin (D) is mechanically kneaded to finely divide the org. pigment A. The inorg. salt B and the solvent C are removed by washing, an aq. paste (D) of the resultant treated pigment and a resin (E) which is solid at ordinary temp. are heated and kneaded and the water is removed. The resultant resin coated pigment (F) and a binder resin (G) are heated and kneaded to obtain the objective toner matrix particles for developing an electrostatic charge image.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner base particle for developing an electrostatic image used for developing an electrostatic latent image in electrophotography, electrostatic recording, electrostatic printing, and the like, and the toner base particle. And a developer formed using the toner. More specifically, when copying or the like is performed using magenta, cyan, yellow, and black toners, a clear and sufficient color reproducibility, a toner mother particle for developing an electrostatic image capable of obtaining color development, and the toner mother particles are provided. The present invention relates to a toner and a developer formed by use.

[0002]

2. Description of the Related Art In recent years, the development of full-color images in copying machines, printers, and the like has been rapidly progressing, and their practical use has been greatly increased. However, compared to photographs and printed matter, it is hard to say that a full-color electrophotographic image currently in practical use has reached a satisfactory image quality. In recent years, with the advancement and development of computers, high-definition televisions, and the like, there is a strong demand for a method of forming a higher-definition full-color image. For this reason, there is a strong demand for further improving the quality of full-color electrophotographic images.

In electrophotography, an electrostatic latent image is generally developed using toner. The methods are roughly classified into a method using a two-component developer in which a small amount of toner is dispersed in a medium called a carrier, and a method using a one-component developer without using a carrier. For full color electrophotography,
A two-component developer in which a carrier and a toner are mixed and used is often used.

In color image formation by full-color electrophotography, all colors are reproduced by using three color toners of three primary colors, magenta, cyan and yellow, and preferably four color blacks for inking. Things.
In this method, for example, light from a document is first subjected to analog or digital color separation and guided to a photoconductive layer of a photoreceptor to form an electrostatic latent image of the first color. Subsequently, the toner is held on a recording medium such as paper through a development and transfer process. Further, for the second and subsequent colors, the above-described steps are sequentially performed a plurality of times, and a plurality of color toners are superimposed on the same recording medium, and a final full-color image is obtained by one-time fixing.

The use of full-color copying machines, full-color printers, and the like to form full-color images on transparent substrates such as sheets for overhead projectors (hereinafter, abbreviated as OHP) has been increasing. As with the most common conventional black toner, the toner used for full-color image formation is required to have various characteristics, such as stable chargeability and good fluidity,
Transparency, sharpness, color reproducibility and the like are further required. That is, since a full-color image is obtained by superimposing a plurality of color toners on the material to be transferred as described above, if the light transmittance of each toner is insufficient, color reproducibility is deteriorated and a clear image is obtained. It is difficult to obtain an image. Especially OH
This phenomenon is remarkable when a full-color image is formed on a transparent substrate such as a sheet for P, and it is difficult to obtain a good transparent image.

As a countermeasure, it is conceivable to increase the degree of dispersion of the pigment, that is, to reduce the particle size of the pigment in the toner. Generally, as the particle size of the pigment is reduced to increase the degree of dispersion, the transparency of the pigment dispersion is improved. However, ordinary dispersing machines such as a sand mill, a three-roll mill, a ball mill, and an extruder mainly break down the secondary particles of the pigment (primary particles are weakly agglomerated) into primary particles. With the disperser described above, it is difficult to make the pigment finer. By using a high-speed sand mill or the like, it is possible to further refine the pigment depending on the kind of the pigment, but it requires a very large amount of energy.

As a means for making the primary particles fine, there is known a method in which a pigment dissolved in a strong acid such as concentrated sulfuric acid or polyphosphoric acid is poured into cold water to precipitate the pigment as fine particles. In this method, the pigments that can be used are significantly limited in terms of solubility and stability of the pigment in strong acids. Further, since the pigment finely divided by this method causes strong secondary agglomeration when dried, it is very difficult to re-disperse the dried pigment to primary particles.

As another method for making the pigment finer, there is known a method in which the pigment and the solid resin are heated and kneaded with a two-roll mill or a Banbury mixer while being heated. However, since pigments generally grow at high temperatures, in such a method, the end point is reached when mechanical crushing and crystal growth are in an equilibrium state, and there is a limit to the fineness of the pigment.

Further, as a method of making the primary particles of the pigment fine, a mixture of the pigment and a water-soluble inorganic salt such as salt is moistened with a small amount of a water-soluble solvent, kneaded strongly with a kneader or the like, and then mixed with the inorganic salt. There is a method in which the solvent is washed away with water and dried to obtain a pigment having fine primary particles. This method is generally known as a pigmentation method of β-type copper phthalocyanine in which crude copper phthalocyanine is mechanically ground in the presence of a water-soluble organic solvent by using salt as a grinding agent. In this case, the water-soluble organic solvent is used for the function as a binder and for preventing the β-type crystal from being crystallized to the α-type crystal due to the mechanical shearing force of the kneader. In general, this method is called solvent salt milling, and is distinguished from a method of simply mechanically reducing the size without using a grinding agent (called dry milling). In a broad sense, salt milling without using a solvent is also called dry milling. However, in this method, there is a problem that the pigment easily undergoes strong secondary aggregation during drying, and the pigment particle size becomes large.

[0010]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the conventional method, and provides clear and sufficient color reproducibility when a full-color image is formed using a full-color copying machine or printer. It is an object of the present invention to provide a toner base particle for developing an electrostatic image capable of obtaining a color developing property, and a toner and a developer using the toner base particle.

[0011]

Means for Solving the Problems The present inventors have made intensive studies on how to uniformly disperse a pigment as fine particles in a toner. As a result, the terpene phenol resin (D) was used during solvent salt milling. Aqueous paste (D) of finely divided organic pigment (treated pigment) using
(Hereinafter, abbreviated as aqueous paste (D)), and by using a resin-coated pigment (F) obtained by so-called flushing of the aqueous paste (D) as a coloring agent for toner base particles, a far more conventional method can be obtained. The present inventors have found that an image excellent in sharpness and transparency can be obtained, and have reached the present invention.

That is, the first invention provides a mixture comprising at least four components of an organic pigment (A), a water-soluble inorganic salt (B), a water-soluble solvent (C), and a terpene phenol resin (D). An aqueous paste (D) of the treated pigment obtained by mechanically kneading the organic pigment (A) to make the organic pigment (A) fine and then removing the water-soluble inorganic salt (B) and the water-soluble solvent (C) by washing with water; A toner for developing an electrostatic image, wherein a resin-coated pigment (F) obtained by heating and kneading a solid resin (E) and then removing water is kneaded with a binder resin (G) by heating. It is a mother particle.

A second invention is characterized in that the organic pigment (A) is one selected from the group consisting of quinacridone organic pigments, phthalocyanine organic pigments, and azo organic pigments. Are the toner base particles for developing an electrostatic image.

According to a third aspect of the present invention, a terpene phenol resin (D) is used in an amount of 1 to 100 parts by weight of the organic pigment (A).
The toner base particles for developing an electrostatic image according to the first or second aspect of the invention, wherein 100 parts by weight are used.

A fourth invention is characterized in that the water-soluble inorganic salt (B) is used in a weight ratio of 2 to 20 times the water-soluble solvent (C) in the first to third inventions. The toner mother particles for electrostatic image development according to any one of the above.

According to a fifth aspect of the present invention, there is provided an electrostatic image developing method comprising mixing the toner base particles according to any one of the first to fourth aspects of the present invention with an external additive. Toner.

According to a sixth aspect of the present invention, there is provided a developer comprising a mixture of the toner for developing an electrostatic image according to the fifth aspect of the invention and a carrier.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, as organic pigment (A), insoluble azo pigments such as toluidine red, toluidine maroon, hansa yellow, benzidine yellow, pyrazolone red, etc .; Soluble azo pigments, phthalocyanines such as phthalocyanine blue and phthalocyanine green; quinacridones such as quinacridone red and quinacridone magenta; perylenes such as perylene red and perylene scarlet; isoindolinones such as isoindolinone yellow and isoindolinone orange. And dianthraquinonyl red.

Specifically, the following organic pigments can be exemplified.
Indicated by color index (CI) number. CI Pigment Yellow 12, 13, 14, 17, 20, 24, 7
4, 83, 86 93, 109, 110, 117, 12
5, 137, 138, 147, 148, 153, 15
4, 166, 168, CI Pigment Orange 13, 1
6, 36, 43, 51, 55, 59, 61, CI Pigment Red 9, 48, 49, 52, 53, 57, 97,
122, 123, 149, 168, 177, 180, 1
92, 215, 216, 217, 220, 223, 22
4, 226, 227, 228, 238, 240, CI Pigment Violet 19, 23, 29, 30, 37,
40, 50, CI Pigment Blue 15, 15: 1, 1
5: 3, 15: 4, 15: 6, 22, 60, 64, CI
Pigment Green 7, 36, CI Pigment Brown 23, 25, 26, and vulcanized dyes derived from vat dyes.

In the case of the black toner base particles among the toner base particles of the present invention, three color processing pigments of yellow, cyan and red may be obtained, and these three color processing pigments may be used as a colorant. In the case of black toner base particles among the toner base particles of the present invention, use of carbon black as a colorant is not prevented.

The water-soluble inorganic salt (B) used in the present invention
Examples thereof include salt, potassium chloride, sodium sulfate and the like.

The water-soluble solvent (C) used in the present invention
The solvent is not particularly limited as long as it is water-soluble, but a solvent having a high boiling point is preferable from the viewpoint of safety because the temperature rises during salt milling and the solvent is easily evaporated. The water-soluble solvent (C) is added for a binder and an effect of preventing crystallization, and the weight ratio of the water-soluble inorganic salt (B) to the water-soluble solvent (C) is 2 to 2. It is preferably used 20 times, more preferably 3 to 10 times.

Examples of the water-soluble solvent include 2- (methoxymethoxy) ethanol, 2-butoxyethanol,
(Isopentyloxy) ethanol, 2- (hexyloxy) ethanol, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol, triethylene glycol monomethyl ether, liquid polyethylene glycol, 1-methoxy-2- Propanol, 1-ethoxy-
2-propanol, 1-ethoxy-2-propanol,
Dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, low molecular weight polypropylene glycol and the like are used. In addition to the above compounds, a dispersant during salt milling,
An additive such as a plasticizer may be used in combination.

The terpene phenolic resin (D) used in the present invention includes gum terpene phenolic resin, polymerized terpene phenolic resin, disproportionated terpene phenolic resin, hydrogenated terpene phenolic resin, maleated terpene phenolic resin, fumarated terpene phenolic resin. Resin, wood terpene phenol resin, tall oil terpene phenol resin, maleated terpene phenol resin pentaester, maleated terpene phenol resin glycerin ester and the like may be used, and two or more terpene phenol resins may be used in combination. The terpene phenol resin (D) used in the present invention is desirably used in an amount of 1 to 100 parts by weight based on 100 parts by weight of the organic pigment (A). More preferably, it is 5 to 50 parts by weight.
If it is less than 1 part by weight, the effect of coating the pigment surface is small,
Agglomeration tends to increase the pigment particle size. It is considered that salt milling in the presence of the terpene phenol resin (D) can prevent reagglomeration of the finely divided pigment.

The treated pigment obtained by salt milling in the presence of the terpene phenol resin (D) preferably has an average particle size of 1.0 μm or less, more preferably 0.2 μm or less, as measured by laser scattering. preferable. When the treated pigment is small as described above, transparency and sharpness are extremely excellent when an image is formed.

As the resin (E) which is a solid at room temperature, that is, a resin which can be used for flashing, any known solid at room temperature can be used. In consideration of image transparency, a colorless and transparent resin is more preferable. For example, polystyrene, styrene-acrylate copolymer, styrene-butadiene copolymer, chloride resin, styrene-vinyl acetate copolymer, terpene phenol resin modified maleic resin, phenol resin, epoxy resin,
Polyester resin, low molecular weight polyethylene, low molecular weight polypropylene, ionomer resin, polyurethane resin,
Silicone resin, terpene phenolic resin / ester,
Terpene phenol resins and the like can be mentioned. These resins can also be used for dilution and melt-kneading after flushing.

The resin-coated pigment (F) in the present invention can be obtained, for example, as follows. To the aqueous paste (D) of the treated pigment, a resin (E) which is a solid at room temperature and other various additives as necessary are added, and the mixture is mixed and stirred by a mixing and dispersing machine such as a kneader or a super mixer. At this time, heating may be performed if necessary. The pigment content is transferred to the resin in about 10 to 20 minutes. The separated water is removed by decantation, and the remaining kneaded material is heated, if necessary, using two or three rolls to remove the water, and the resin-coated pigment (F) (pigment high concentration chip ).

The toner base particles of the present invention can be obtained according to a conventional method. That is, the binder resin (F) and, if necessary, other charge control agents and additives are added to the resin-coated pigment (F) and premixed with a Henschel mixer or the like, and then melted using an extruder or the like. Perform kneading. Then, after cooling, coarsely pulverized by a hammer mill or the like, finely pulverized by a jet mill or the like, and classified by an air classifier or the like to obtain an average particle size of 5 to 20.
What is necessary is just to obtain a classified product having a predetermined particle size distribution of about μm.

As the binder resin (F), that is, a resin that can be used for melt-kneading after flushing, known resins can be widely used. In consideration of image transparency, a colorless and transparent resin is more preferable. The same type of resin as the normal temperature resin (E) can be used, but the binder resin (F) is not necessarily
Does not need to match the resin (E).

The toner base particles of the present invention preferably contain a charge control agent. As the charge control agent, any known charge control agent can be used, but a colorless or light-colored one which does not affect the color tone of the toner is preferable. For example, an organic metal complex such as a metal complex of an alkyl-substituted salicylic acid (for example, a chromium complex, an aluminum complex, or a zinc complex of ditertiary butyl salicylic acid) can be given.

The toner base particles of the present invention preferably contain various particles as an external additive as a fluidity improver, a cleaning aid and the like. Any known external additives can be used. For example, 0.01 to 0.5 μm silica, alumina, metal oxides such as titanium oxide, silicon carbide, abrasives such as tungsten carbide, zinc stearate,
Lubricants such as fatty acid metal salts such as aluminum stearate,
In addition, it is preferable to add a fine powder of 1 to 50 μm such as polytetrafluoroethylene, polyvinylidene fluoride, polymethacrylate, polystyrene, or silicone. It is also preferable to add a mixture of the above and an external additive obtained by subjecting these fine powders to various surface treatments.

The developer of the present invention is obtained by mixing the above toner and carrier, and can be obtained by a conventionally known method, and is not particularly limited. As the carrier used in the developer of the present invention, all known carriers can be used. In general, carriers constituting a two-component developer are roughly classified into conductive carriers and insulating carriers.
As the conductive carrier, an oxidized or non-acid value iron powder or the like is usually used. A typical example of the insulating carrier is a carrier in which the surface of carrier core material particles made of a ferromagnetic material is uniformly coated with an insulating resin. Examples of the carrier core material include iron oxide (magnetite),
Particles of reduced iron, copper, ferrite, nickel, cobalt and the like and alloys thereof with zinc, aluminum and the like can be given. As the coating resin, known materials such as acrylic resin, epoxy resin, silicone resin, urethane resin, polyacetal resin, polyamide resin, polycarbonate resin, phenol resin, vinyl acetate resin, cellulose resin, polyolefin resin, fluororesin, amino resin, etc. Any one may be used. 20 ~ 2 as a carrier
Those having a size of about 00 μm are preferred. In general, the developer preferably contains 1 to 30% by weight of a toner.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments. In the examples, "parts" indicates parts by weight. [Example 1] Crude copper phthalocyanine: 250 parts (Lionol Blue SL, manufactured by Toyo Ink Manufacturing Co., Ltd.) Sodium chloride: 2500 parts Terpene phenol resin: 100 parts (Mighty G125, average molecular weight 600: manufactured by Yashara Chemical) Diethylene glycol: 200 parts It was charged into a stainless steel 1 gallon kneader (manufactured by Inoue Seisakusho) and kneaded for 3 hours. Next, the mixture was poured into 2.5 liters of warm water, heated to about 80 ° C., and stirred. About 1
After stirring to form a slurry, filtration and washing were repeated 5 times to remove sodium chloride and the solvent, and the solid content was 50%.
A pigment-based aqueous paste was obtained. The flushing step is performed using such an aqueous paste.

Aqueous paste 100.0 parts Unsaturated polyester resin (: room temperature solid resin (E)) 25.0 parts Methanol 0.5 parts The above raw materials were charged into a 1 gallon stainless steel kneader (manufactured by Inoue Seisakusho), and 100 When the mixture was mixed while being heated to ℃, the pigment content was transferred to the resin (flushing) in about 10 minutes. After removing the separated water and solvent from the kneader, the remaining kneaded material was passed five times with a heating-type two roll,
A high concentration chip (resin-coated pigment) was obtained.

The above unsaturated polyester resin (: binder resin (G)) 100.0 parts High pigment concentration chip 5.0 parts Negative charge control agent 4.0 parts Next, the above raw materials are melt-kneaded with an extruder. And
After cooling, the mixture is roughly pulverized with a hammer mill and further finely pulverized with a jet mill to obtain toner base particles having an average particle diameter of 10.0 μm. 0.4 parts of titanium oxide fine powder is added to 100 parts of the toner base particles and mixed with a Henschel mixer to obtain a toner.

6 parts of the obtained toner was added to 100 parts of ferrite and mixed with a ball mill to obtain a developer. Using this developer, a commercially available full-color copying machine (CLC
350, manufactured by Canon Inc.), clear and sufficient color reproducibility and coloring were obtained. In particular, when an image was formed on an OHP sheet, remarkable improvement in transparency was observed as compared with the conventional case. Also, the obtained toner was melted by hot pressing to form a uniform thin layer on a glass plate, and the dispersion state of the pigment was observed with an optical microscope. Was confirmed.

Example 2 In place of the crude copper phthalocyanine of Example 1, a yellow pigment (Hoster Palm Yellow) was used.
An aqueous paste was prepared in the same manner as in Example 1 using 260 parts (H3G: Hansa Yellow system, manufactured by Hoechst) and then flushed in the same manner as in Example 1 to obtain toner base particles, a toner, and a developer. When an image was formed using a full-color copying machine, clear and sufficient color reproducibility and color development were obtained. The dispersion state of the obtained toner was also good.

Example 3 An aqueous paste was prepared in the same manner as in Example 1 except that 250 parts of a red pigment (Hoster Palm Pink E: quinacridone type, manufactured by Hoechst) was used instead of the crude copper phthalocyanine of Example 1. Thereafter, flushing was performed in the same manner to obtain toner base particles, toner and a developer, and an image was formed using a full-color copying machine in the same manner as in Example 1. As a result, clear and sufficient color reproducibility and coloring were obtained. Was done. The dispersion state of the obtained toner was also good.

Example 4 Yellow pigment: 250 parts (Paliotol yellow D-1819: isoindolinone type, manufactured by BASF) Sodium chloride: 2500 parts Terpene phenol resin: 50 parts (Mighty A G150, average molecular weight 700: A water-based paste was prepared in the same manner as in Example 1 using diethylene glycol: 200 parts (manufactured by Yashara Chemical Co., Ltd.), and flushed in the same manner to obtain toner base particles, a toner and a developer, and full-color copying was performed in the same manner as in Example 1. When an image was formed using a printer, clear and sufficient color reproducibility and color development were obtained. The dispersion state of the obtained toner was also good.

[Examples 5 to 7] 240 parts of a red pigment (chromophtal red A-2B: diaminodianthranil type, manufactured by CIBA) instead of 250 parts of crude copper phthalocyanine of Example 1 (Example 5) 200 parts of blue pigment (Lionogen blue 6505: indasulene type, manufactured by Toyo Ink Mfg. Co., Ltd.) (Example 6), 250 parts of red pigment (Pariotor Red L3670: perylene type, manufactured by BASF) (Example) 7) An aqueous paste was prepared in the same manner as in Example 1 by using
When a toner and a developer were obtained, and an image was formed using a full-color copying machine in the same manner as in Example 1, clear and sufficient color reproducibility and coloring were obtained. The dispersion state of the obtained toner was also good.

Comparative Example 1 Aqueous paste of crude copper phthalocyanine (Lionol Blue SL, manufactured by Toyo Ink Mfg. Co., Ltd., solid content: 50%) 100.0 parts Unsaturated polyester resin (: room temperature solid resin (E) 25.0 parts Methanol 0.5 parts When the above-mentioned raw materials were mixed while heating to 100 ° C. in a kneader, the pigment content was transferred to the resin (flushing) in about 10 minutes. After removing the separated water from the kneader, the remaining kneaded material was passed five times with a heated two-roll mill to obtain a high-concentration pigment chip. In place of the pigment high-concentration chips used in Example 1, the above-described pigment high-concentration chips not subjected to the solvent salt milling treatment were used to obtain toner base particles, a toner and a developer in the same manner as in Example 1. When an image was formed using a commercially available full-color copying machine, a clear image with high chroma was obtained, but the transparency on the OHP sheet was inferior to that of Example 1.

Comparative Examples 2 to 7 Purified water was added to a yellow pigment (Poster Palm Yellow H3G: Hansa Yellow, manufactured by Hoechst) to give a solid content of 50%.
% Of an aqueous paste (Comparative Example 2), and purified water was added to a red pigment (Poster Firm Pink E: quinacridone type, manufactured by Hoechst) to form an aqueous paste having a solid content of 50% (Comparative Example 3). Purified water was added to a yellow pigment (Paliotol Yellow D-1819: isoindolinone type, manufactured by BASF) to obtain a solid content of 50%.
% Of an aqueous paste (Comparative Example 4), purified water was added to a red pigment (Chromophthal Red A-2B: diaminodianthranil type, manufactured by CIBA), and the solid content was 5%.
A 0% aqueous paste was formed (Comparative Example 5). Purified water was added to a blue pigment (Lionogen Blue 6505: Induslen-based, manufactured by Toyo Ink Mfg. Co., Ltd.) to obtain an aqueous paste having a solid content of 50%. (Comparative Example 6), and purified water was added to a red pigment (Palitol Red L3670: perylene-based, manufactured by BASF) to form an aqueous paste having a solid content of 50% (Comparative Example 7). Using the above-mentioned pigment high-concentration chips which were not subjected to the solvent salt milling treatment in the same manner as in Example 1, toner base particles, a toner and a developer were obtained in the same manner as in Comparative Example 1, and similarly a commercially available full-color copying machine was used. When an image was formed, the result was the same as in Comparative Example 1.

[Comparative Example 8] Unsaturated polyester resin 100.0 parts Blue pigment (Lionol Blue SL, manufactured by Toyo Ink Mfg. Co., Ltd.) 3.0 parts (Note: Normal without solvent salt milling or flashing) Pigment formed through the drying step of (1) Negative charge control agent 4.0 parts The above mixture was melt-kneaded with an extruder, and then toner mother particles, toner and developer were obtained in the same manner as in Example 1. An image was formed using a commercially available full-color copying machine. As a result, the color reproducibility, coloring and transparency of the image were significantly lower than those of Example 1.

Comparative Examples 9 to 14 Instead of the blue pigment of Comparative Example 8, a yellow pigment (Poster Palm Yellow H3G: Hansa Yellow, manufactured by Hoechst) (Comparative Example 9), a red pigment (Poster Firm Pink E: Quinacridone) System, manufactured by Hoechst) (Comparative Example 10), yellow pigment (Paliotol Yellow D-1819: isoindolinone system, manufactured by BASF) (Comparative Example 11), red pigment (Chromophthal Red A-2B: diaminodianthranil system) (Manufactured by CIBA) (Comparative Example 12), Blue pigment (Lionogen Blue 6505: Indasulene based, manufactured by Toyo Ink Mfg. Co., Ltd.) (Comparative Example 13), Red pigment (Palio Tol Red L3670: Perylene based, BASF) (Comparative Example 14), except that each was used, to obtain toner base particles, a toner and a developer in the same manner as in Comparative Example 1, and similarly commercially available When a full-color copying machine was used to form an image, the color reproducibility, color development, and transparency of the image were significantly reduced as in Comparative Example 8.

[0045]

As described above, according to the present invention, toner base particles for electrostatic image development, and a toner and a developer having a small particle diameter of the pigment in the toner, and providing clear and sufficient color reproducibility and color development can be obtained. When the dispersion state of the pigment in the toner was observed with an optical microscope, it was confirmed that the dispersion state was very good without aggregation.

Claims (6)

[Claims] 1. A mixture comprising at least four components of an organic pigment (A), a water-soluble inorganic salt (B), a water-soluble solvent (C), and a terpene phenol resin (D) is mechanically kneaded. An aqueous paste (D) of a treated pigment obtained by pulverizing the organic pigment (A) and then removing the water-soluble inorganic salt (B) and the water-soluble solvent (C) with water; And a resin-coated pigment (F) obtained by removing water after heating and kneading the mixture with a binder resin (G). 2. The electrostatic image development according to claim 1, wherein the organic pigment (A) is one selected from the group consisting of quinacridone-based organic pigments, phthalocyanine-based organic pigments, and azo-based organic pigments. For toner mother particles. 3. The toner base particles for developing an electrostatic image according to claim 1, wherein the terpene phenol resin (D) is used in an amount of 1 to 100 parts by weight based on 100 parts by weight of the organic pigment (A). 4. The electrostatic charge according to claim 1, wherein the weight ratio of the water-soluble inorganic salt (B) to the water-soluble solvent (C) is 2 to 20 times. Toner base particles for image development. 5. An electrostatic image developing toner comprising a mixture of the toner particles for electrostatic image development according to claim 1 and an external additive. 6. A developer comprising a mixture of the toner for developing an electrostatic charge image according to claim 5 and a carrier.