JPH0895295A - Electrostatic charge image developing toner, its production and developer - Google Patents

Abstract

PURPOSE: To maintain an excellent picture quality for a long period even under high-temp. and humidity working conditions by granulating a liq. prepared by dissolving or dispersing a toner material in solvent in an aq. medium contg. an inorg. dispersant and a specified surfactant and then removing the solvent. CONSTITUTION: A liq. prepared by dissolving or dispersing a toner material contg. polyester resin and colorant in a solvent capable of dissolving the polyester resin is granulated in an aq. medium contg. an inorg. dispersant and a surfactant shown by the formula. and then the solvent is removed to obtain the electrostatic charge image developing toner. In the formula, R is hydrogen atom or a 1-20C alkyl, (m) and (n) are respectively 0, 1 or 2, (m+n)>=1, (p) and (q) are respectively 0 or 1, (p+q)>=1, (r) is (p+q), and A is Na, K or NH4 . The toner freed from solvent is cleaned preferably with the acids such as hydrochloric acid and nitric acid and reacting with tricalcium phosphate to make the inorg. deposit water-soluble.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic charge image which visualizes an electrostatic charge image formed on the surface of a photoreceptor in electrophotography, electrostatic recording and the like, a method for producing the same and a toner for using the toner. Related to the developer.

[0002]

2. Description of the Related Art An electrophotographic system is disclosed in US Pat.
No. 7,691, British Patent Nos. 1,165,406 and 1,165,405, a photoconductive material is uniformly applied to a photoreceptor. A charging step for imparting an electrostatic charge, an exposure step for irradiating light to form an electrostatic latent image, a developing step for adhering toner to a latent image portion, a transfer step for transferring to a toner image support, a heat treatment for the toner image, It consists of a fixing process to fix it to the image support with pressure, flash light, etc., a cleaning process to remove the toner remaining on the photoconductor, and a static elimination process to remove the electrostatic charge on the photoconductor and return it to the initial state. Repeatedly produces several prints.

As a positively chargeable toner for developing an electrostatic charge image used in the field of electrophotography, a toner using a polyester resin obtained by subjecting a glycol having a bisphenol skeleton and a polybasic acid to a condensation reaction (Japanese Examined Patent Publication No. 52). -2542
No. 0), a toner using a polystyrene resin (JP-B-44-16118), and a toner using a styrene-butyl methacrylate copolymer resin (JP-B-56-1114).
3), a toner using a bisphenol type epoxy resin obtained by reacting bisphenol with epichlorohydrin (JP-A-57-96354), and the like.

[0004]

By the way, in recent years, with the diversification of information, as for the method of expressing information, instead of the conventional image formation with monochrome toner, image formation with color toner is required. Came. In many cases, a toner using a polyester resin having excellent color tone reproducibility is used for such color processing. Further, there is a demand for a toner having a high resolution, that is, a toner having a small particle size capable of fine expression in response to the movement of higher density of information.

However, in response to such market trends,
The conventional so-called pulverization toner in which a polyester resin, a colorant and other additives are melt-kneaded and then pulverized has various problems described below. (1) In order to obtain a toner having excellent color tone reproducibility, a low-molecular-weight polyester resin that sharply melts at the time of fixing is required. However, since it has a low molecular weight, the colorant and other additives are not dispersed during melt-kneading. If it is sufficient, the color tone of the fixed image will be poor, and the composition of the toner will be inhomogeneous, resulting in poor image quality. (2) Since it is a low molecular weight polyester resin, the melt-kneaded product is easily over-milled and the yield is low. Further, finely pulverized particles scatter during printing to deteriorate image quality or pollute the environment.

As another manufacturing method other than the pulverization method, after dissolving the toner material in a solvent, the solution is treated with an organic dispersant,
For example, it is known to granulate to a predetermined particle size in an aqueous medium containing methylcellulose and then remove the solvent (Japanese Patent Laid-Open No. 1-257856). However, the toner obtained by this method also has many problems. An organic dispersant having a high affinity for water remains on the surface of the toner particles from which the solvent has been removed, resulting in poor charging properties and environmental stability, which are basic characteristics that the toner must have, and are far from practical use. Furthermore, since the residual organic dispersant covers the toner surface to form a thin layer, the toner meltability at the time of fixing is reduced and the original color tone is not expressed, or when used as a full-color toner, the transparency of the fixed toner is reduced. Inferior, the toning property due to mixing of the three primary colors may not remain. Further, since the toner particles are spherical in shape, the untransferred toner on the photoconductor after transferring the toner to the image support is poorly cleaned and cannot be repeatedly used. The present invention solves the above problems, has excellent color tone reproducibility, can reduce the particle size, and is a toner that does not cause deterioration of image quality and cleaning failure even under repeated use under various environmental conditions. The present invention provides a method for producing the same and a developer using the same.

[0007]

According to the present invention, a liquid obtained by dissolving or dispersing a toner material containing a polyester resin and a colorant in a solvent in which the polyester resin can be dissolved is mixed with an inorganic dispersant and the general formula (I). )

[Chemical 3] (In the formula, R represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, m and n are 0, 1 or 2, and m +
n is at least 1 and p and q are 0 or 1 respectively.
And p + q is chosen to be at least 1, r
Is p + q and A is Na, K or NH ₄ ) and is granulated in an aqueous medium containing
The present invention relates to an electrostatic image developing toner obtained by removing the solvent, and a developer containing the toner and a carrier. Further, the present invention is to dissolve or disperse a toner material containing a polyester resin and a colorant in a solvent in which the polyester resin can be dissolved, and then to disperse the toner material and an inorganic dispersant in the surfactant represented by the general formula (I). The present invention relates to a method for producing a toner for developing an electrostatic charge image, which comprises granulating into a predetermined particle size under high-speed shearing in an aqueous medium containing an agent, and then removing the solvent.

A polyester resin is used as the binder resin of the electrostatic image developing toner according to the present invention. The following may be mentioned as raw materials for the polyester resin. As the alcohol component, polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl)
Propane, polyoxypropylene (3,3) -2,2-
Bis (4-hydroxyphenyl) propane, polyoxyethylene (2,0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2,0)-
General formula (II) such as polyoxyethylene (2,0) -2,2-bis (4-hydroxyphenyl) propane

[Chemical 4] (Wherein, R ¹ and R ² are ethylene groups or propylene groups, x and y are each an integer of 1 or more, and the average value of the sum thereof is 2 to 7), Ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, isopentyl glycol, hydrogenated bisphenol A, 1,3-butanediol,
1,4-butanediol, neopentyl glycol, xylylene glycol, 1,4-cyclohexanedimethanol, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, bis- (β-hydroxyethyl) terephthalate, tris- (β -Hydroxyethyl) isocyanurate, 2,2,4-trimethylolpentane-1,3-diol and the like, and a hydroxycarboxylic acid component can be further added. For example, p-oxybenzoic acid, vanillic acid, dimethylolpropionic acid, malic acid, tartaric acid, 5-hydroxyisophthalic acid and the like.

Specific examples of the acid component include malonic acid, succinic acid, glutaric acid, dimer acid, phthalic acid, isophthalic acid, terephthalic acid, isophthalic acid dimethyl ester, terephthalic acid dimethyl ester, terephthalic acid monomethyl ester, tetrahydrophthalic acid, Methyltetrahydrophthalic acid, hexahydrophthalic acid, dimethyltetrahydrophthalic acid, endomethylenehexahydrophthalic acid, naphthalenetetracarboxylic acid, diphenolic acid, trimellitic acid, pyromellitic acid, trimesic acid, cyclopentanedicarboxylic acid, 3,3 ′, 4,4′-Benzophenonetetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, 2,2-bis- (4-carboxyphenyl) propane, trimellitic anhydride and 4,4-diamino Obtained from phenylmethane Diimidocarboxylic acid, tris-
(Β-carboxyethyl) isocyanurate, isocyanurate ring-containing polyimide carboxylic acid, tolylene diisocyanate, xylylene diisocyanate or isophorone diisocyanate trimerization reaction product and isocyanate ring-containing polyimide carboxylic acid obtained from trimellitic anhydride , One or more of these are used. Of these, the use of a crosslinking component such as a trivalent or higher polycarboxylic acid or polyhydric alcohol may be preferable in terms of stability such as fixing strength and offset resistance.

The polyester resin obtained from these raw materials is manufactured by a usual method. For example, an acid component and an alcohol component are charged into a reaction vessel at a predetermined ratio, and the reaction is started at a temperature of 150 to 190 ° C. in the presence of an inert gas such as nitrogen gas. By-produced low molecular weight compounds are continuously removed from the reaction system. After that, the reaction temperature is further increased to 200 to 2
The temperature is raised to 50 ° C. to accelerate the reaction and obtain the target polyester resin. When producing a polyester resin, when the carboxylic acid component used is a free carboxylic acid that does not contain an ester group, it is represented by an esterification catalyst, for example, an organic metal such as dibutyltin dilaurate or dibutyltin oxide, or tetrabutyl titanate. 0.1 to 1% by weight based on the total amount of raw toner materials charged
When the carboxylic acid component is a lower alkyl ester, it is preferable to use a transesterification catalyst, for example, a metal acetate such as zinc acetate, lead acetate, magnesium acetate, zinc oxide, a metal oxide such as antimony oxide, or tetrabutyl. It is preferable to use a metal alkoxide such as titanate in an amount of 0.005 to 0.05% by weight based on the total amount of the raw materials charged.

The glass transition temperature of the polyester resin as the binder resin is preferably 35 to 100 ° C., and 50
It is particularly preferable to adjust the temperature to ˜90 ° C. When the glass transition temperature is lower than 35 ° C., the toner is apt to cause blocking (a phenomenon in which toner particles aggregate and agglomerate) during storage or in a developing machine. On the other hand, when the glass transition temperature exceeds 100 ° C., a large amount of heat energy is required for fixing the toner.
In the toner of the present invention, the above polyester resin is used
One or more species may be used in combination, or another resin may be added and used. Other resins include silicone resin, epoxy resin, xylene resin, diene resin, styrene resin, acrylic resin, styrene / acrylic resin, phenol resin, terpene resin, coumarone resin, amide resin, amide imide resin, butyral resin, urethane resin. , Ethylene / vinyl acetate resin, etc. In the present invention, it is preferable to use a polyester resin as a main component and other resins in the toner in an amount of 0 to 30% by weight. The binder resin is preferably blended in the toner in an amount of 60 to 95% by weight. If this amount is less than 60% by weight, the binding force to the toner image support is weak and the toner image is likely to be lost when the toner image support is bent or rubbed, and information is likely to be lost. On the other hand, if it exceeds 95% by weight, the toner image hiding power tends to be insufficient, and poor print quality tends to occur.

The toner of the present invention contains a colorant and, if necessary, other additives. Carbon black, acetylene black, iron black, as colorant for black toner,
Aniline black, cyanine black, etc.
Carbon black is preferably used. Naphthol yellow S (C.
I.10316), Hansa Yellow 10G (CI1171
0), Hansa Yellow 5G (CI11660), Hansa Yellow G (CI11680), Hansa Yellow R (CI12)
710), Pigment Yellow L (CI12720), Benzidine Yellow G (CI21095), Permanent Yellow NCG (CI20040), Balkan First Yellow 5G (CI21220), Quinoline Yellow (CI4).
7005), Permanent Yellow FGL (CI1176)
7), permanent yellow HR (CI21108), pigment yellow (CI21105) and the like.

Permanent Red 4 as a red colorant
R (CI12070), Para Red (CI1212
0), Brilliant Fast Scarlet (CI123
15), Brilliant Carmine BS (CI1235
1), Permanent Red F4R (CI12335),
Vulcan Fast Rubin B (CI12320), Light Fast Red Toner B (CI12450), Lake Red C (CI15585: 1), Brilliant Carmine 6B (CI15850: 1), Rhodamine Lake B (CI45170: 2), Pigment Red (CI7).
3915) and the like.

Cobalt blue (CI
77346), alkaline blue rake (CI4275
0: 1), Victoria Blue Rake (CI44045:
2), metal-free phthalocyanine blue (CI7410
0), phthalocyanine blue (CI74160), fast sky blue (CI74180: 1) and the like. Furthermore, as orange colorants, permanent orange (CI12075), vulcan first orange GG (CI21165), indanthrene brilliant orange RG (CI59300), as purple colorants, first violet B (CI12321), methyl violet lake (CI42535), Pigment Green B (CI10006), Acid Green Lake, Phthalocyanine Green (CI74
260) and other organic pigments, inorganic pigments and dyes. The above colorants can be used alone or as a mixture. These colorants are preferably added in the toner in an amount of 0.1 to 15% by weight.

As the other additive which is a toner material, various additives can be mentioned. For example, in order to obtain a toner for developing an electrostatic image having magnetism, a magnetic or magnetizable toner material such as hematite and magnetite containing oxides of iron, cobalt and nickel may be added. Further, as an anti-offset agent, lower alcohol esters of fatty acids such as butyl stearate and propyl stearate, higher alcohol esters of fatty acids such as casta wax and diamond wax, palm aceti, Hoechst wax E, hexti wax OP, carnauba wax, etc. Higher Alcohol Ester, Bisamide Blast Flow, Amide 6L, 7S, 6H, Hoechst Wax C
Alkylene bis fatty acid amide compounds such as ethylene, propylene, butene, hexene, heptene, octene, nonene, decene, 3-methyl-1-butene, 3-methyl-
Examples thereof include polymers of olefin monomers such as 2-pentene and 3-propyl-5-methyl-2-hexene, and copolymers of the above olefin monomers with acrylic acid, methacrylic acid, butyl acetate and the like. Of these, polypropylene is particularly preferable. These are 0.1 to 1 for toner
It is preferable to add 0% by weight, particularly 0.1 to 5% by weight. If the amount is less than 0.1% by weight, offset may occur depending on the device on which the toner is mounted. If it exceeds 10% by weight, the powder fluidity of the toner is lowered and the developability is deteriorated, or the transparency of the toner is lowered and it becomes difficult to obtain a desired color tone.

It is preferable to use a positive or negatively chargeable charge control agent in the toner of the present invention. Examples of the positive charge control agent include Bontron BY, which is a nigrosine dye of an azine compound, and Bontron P-, which is a quaternary ammonium salt.
51 (above, trade name manufactured by Orient Chemical Industry Co., Ltd.), quaternary ammonium salt molybdenum complex TP-302, TP
-415 (trade name of Hodogaya Chemical Co., Ltd.), quaternary ammonium salt copy charge PSY VP203
8. Copy blue PR of triphenylmethane derivative
(The above are product names manufactured by Hoechst Co., Ltd.), LRA-901 (product name manufactured by Nippon Carlit Co., Ltd.) and the like. As the negatively chargeable charge control agent, for example, the following compounds can be used. Bontron S-34, a metal-containing azo dye, E-82, an oxynaphthoic acid-based metal complex, E-84, a salicylic acid-based metal complex, E-89, a phenol-based condensate (these are trade names of Orient Chemical Industry Co., Ltd.). ), Quaternary ammonium salt copy charge NEG VP2036, copy charge NX VP434 (above, Hoechst brand name), boron complex LR-147 (Nippon Carlit).
(Trade name, manufactured by Co., Ltd.) and the like. These charge control agents may be used alone or as a mixture, and may be added to the toner in an amount of 5.0.
It is preferable to add less than or equal to 5% by weight, particularly 0.5 to 5% by weight. If the addition amount is less than 0.5% by weight, the chargeability of each toner particle becomes non-uniform and insufficiently charged toner particles are mixed, which lowers the developability and scatters to contaminate the inside of the machine and the work environment. Tend to do. If it exceeds 5% by weight, the charge amount is high and the printing density is low from the initial stage, the transferability from the photoconductor to the toner support is poor, and the cleaning property of the transfer residual toner adhering to the photoconductor is poor. Problems tend to occur. From these points, the most preferable range is 0.5 to 3% by weight.

A known silica powder may be further added to the toner of the present invention. Such silica powders include Aerosil R972, R974, Silica D
-17, T-805, R-812, RA200, HRX
-C (above, manufactured by Nippon Aerosil Co., Ltd.), Taranox 500 (manufactured by Tarco), Cab-O-Sil M-
5, MS-7, MS-75, HS-5, EH-5, S-
17, TS-72 (above, manufactured by Cabot), hydrophobic silica HDKH2000 / 4 (manufactured by Wacker Chemicals), and the like. When using these, it is preferable that the content of the toner is 3% by weight or less.

In the present invention, the toner material containing the polyester resin, the colorant and other additives used as required is dissolved or dispersed in a solvent in which the polyester resin can be dissolved. Whether or not a polyester resin can be dissolved depends on the constituent components of the polyester resin, the molecular chain length, the degree of three-dimensionalization, etc., so it cannot be said unequivocally, but generally hydrocarbons such as toluene, xylene, and hexane are included. Halogenated hydrocarbons such as methylene chloride, chloroform, dichloroethane and dichloroethylene, alcohols and ethers such as ethanol, butanol, benzyl alcohol ethyl ether, benzyl alcohol isopropyl ether, tetrahydrofuran and tetrahydropyran, methyl acetate, ethyl acetate, butyl acetate, acetic acid Esters such as isopropyl, acetone, methyl ethyl ketone, diisobutyl ketone, dimethyl oxide, diacetone alcohol, ketones such as cyclohexanone and methylcyclohexanone, and acetal are used.

These solvents dissolve the polyester resin, and it is not necessary to dissolve the colorant and other additives. The colorant and other additives may be dispersed in the polyester resin solution. The amount of solvent used is not limited, but may be any viscosity as long as it can be granulated in an aqueous medium. The ratio of the toner material (former) containing the polyester resin, the colorant, and other additives optionally used to the solvent (latter) is 10/90 to 50/50 (former / latter weight ratio). It is preferable in terms of easiness of granulation and final toner yield.

The liquid (toner mother liquor) of the toner material containing the polyester resin dissolved or dispersed in the solvent and the colorant and other additives used as necessary has an average particle diameter of preferably 0.7 to 5 μm. More preferably 0.7
It is granulated to have a predetermined particle size in an aqueous medium containing an inorganic dispersant having a particle size of ˜4 μm, particularly preferably 1 to 4 μm. When the average particle size of the inorganic dispersant is less than 0.7 μm or more than 5 μm, it is difficult to obtain a toner having a target particle size, and the image characteristics tend to deteriorate. Water is mainly used as the aqueous medium.
The mixing ratio of the aqueous medium and the toner mother liquor is determined from the yield per unit work, the stable production of particles, etc., and the aqueous medium / mother liquor = 99 /
1-30 / 70, preferably 90 / 10-50 / 50,
It is particularly preferably 80/20 to 60/40 (both by weight). As the inorganic dispersant, tricalcium phosphate and / or hydroxyapatite is preferable. The reason for this is that there is very little adverse effect on the granulation property during production and its stability, and further on the properties of the toner obtained.
The average particle size referred to here is the sub-micron particle analyzer Coulter (SUB-MICRON PARTICLE ANA
LYZER COURTER model N4MD (manufactured by COURTER ELECTRONICS) is a value measured in a state of being dispersed in an ethanol solution. Dispersion in an ethanol solution was performed by ultrasonic treatment for 3 to 5 minutes.

The amount of the inorganic dispersant used is determined according to the particle diameter of the particles to be granulated, but it is generally 0.1 to 15% by weight, preferably 1 to 10% by weight based on the toner mother liquor. ,
In particular, in order to obtain a toner having a small particle size of 4 to 9 μm, which is the main object of the present invention, the range is 2 to 8% by weight. If the amount of the inorganic dispersant used is less than 0.1% by weight, it is difficult to perform good granulation. If the amount of the inorganic dispersant used exceeds 15% by weight, a large amount of unnecessary fine particles are generated and the target particles are produced in a high yield. Hard to get. In order to obtain a toner of 9 to 15 μm, 1 to 2% by weight is usually used.
You can do this.

In the present invention, an anionic surface active agent represented by the above general formula (I) is used as an auxiliary agent in an aqueous medium containing an inorganic dispersant in order to favorably granulate the toner mother liquor. Add agent. Moreover, you may use together other surfactant. Specific examples of the surfactant represented by the general formula (I) are shown below.

[0023]

[Chemical 5]

These surfactants are contained in the toner mother liquor in an amount of 1 × 10 ^-5 to 1% by weight, and further 1 × 10 ^{-4 to} 0.5.
It is preferable to use it in an amount of 1% by weight, particularly 1 × 10 ^{−4 to} 0.2% by weight, because the effects of environmental resistance and printing life are high. Granulation of the toner mother liquor in an aqueous medium containing an inorganic dispersant and a surfactant is preferably carried out under high speed shear. The toner mother liquor dispersed in the aqueous medium is granulated to have an arbitrary particle size as desired. Most toner particle sizes on the market are in the range of 15 to 9 μm, and it is easy to granulate these particle sizes by the toner manufacturing method of the present invention, but especially 4 to 9 μm.
It is effective in producing the toner particles of m with high yield and high quality.

If a toner having such a relatively small particle size is to be produced, the yield is extremely low in the conventional pulverizing method and a large amount of unnecessary fine particle toner is contained. Toner adheres to the white background of the support (paper, OHP, etc.) (hereinafter abbreviated as fog), or scatters to contaminate the surroundings of the equipment or the work environment. Further, the method of granulating to a predetermined particle size in an aqueous medium containing an organic dispersant is also not preferable because a large amount of fine particle toner is produced. Compared to these, the production method of the present invention has an extremely small amount of unnecessary fine particle toner, and a toner having a desired particle size can be obtained in high yield.

To granulate the toner of the present invention under high speed shearing, an apparatus equipped with a high speed shearing mechanism can be used.
There are various types of high-speed dispersers as a device equipped with a high-speed shearing mechanism, and among them, a homogenizer is preferable. The homogenizer allows substances that are incompatible with each other (in the present invention, an aqueous medium containing an inorganic dispersant and a toner mother liquor) to pass through a narrow gap between the casing and a rotor that rotates at a high speed, so that a certain liquid does not react with the liquid. This is a device for dispersing insoluble substances into fine particles. Examples of such homogenizers include TK homomixer, line flow homomixer (above, manufactured by Tokushu Kika Kogyo Co., Ltd.), Silverson homogenizer (manufactured by Silverson Co.), and Polytron homogenizer (manufactured by KINEMATICA AG).

The stirring conditions using the homogenizer are preferably 2 m / sec or more at the peripheral speed of the rotor blades. If it is less than this range, atomization tends to be insufficient. In the present invention, the solvent is removed after the toner mother liquor is granulated in an aqueous medium containing an inorganic dispersant and a surfactant. The solvent may be removed at room temperature and atmospheric pressure, but it takes a long time to remove it. Therefore, it is preferable to perform the removal under a temperature condition that is lower than the boiling point of the solvent and has a difference from the boiling point of the solvent of 80 ° C. or less. The pressure may be normal pressure or reduced pressure, but it is preferable that the pressure is reduced to 20 to 150 mmHg.

It is preferable to remove the solvent sufficiently until the particle shape of the granulated particles in the aqueous medium does not substantially change after removal of the solvent, and then remove the inorganic dispersant and the like. Actually, 50% by weight or more of the total amount of the solvent charged,
Further, it is preferable to remove 70% by weight or more, particularly 80% by weight or more. When the amount of the solvent to be removed is less than 50% by weight, when the inorganic dispersant is removed, the particles formed by coalescing (a phenomenon in which agglomerated toner particles aggregate to form large particles) are substantially formed. And it is difficult to obtain toner particles having a target particle size. The final toner particles are preferably controlled to have a residual solvent content of less than 1% by weight, particularly less than 0.5% by weight, from the viewpoints of environmental resistance, life at the time of mounting, prevention of toner adhesion to the photoconductor, and the like. Therefore, a step of further removing the solvent by vacuum drying, vibration fluidization drying or the like may be provided.

After removing the solvent, the toner of the present invention is removed by reacting with tricalcium phosphate or hydroxyapatite, such as hydrochloric acid, nitric acid, formic acid, and acetic acid, and washing with an acid which makes these inorganic dispersants water-soluble. Is preferred. Further, it is preferable to wash the surface with sufficient water to remove the surfactant and the acids. As a result, unnecessary substances remaining on the surface of the toner can be removed to obtain the original composition of the toner, and as a result, the charging characteristics of the toner can be maintained at a high level. In other words, by preventing the generation of undesired low-charged toner or reversely-charged toner, precise development can be performed on the electrostatic latent image, and image quality such as image density, resolution, gradation and fog can be improved. And shows excellent performance. Further, since the toner does not scatter, it does not pollute the working environment and is excellent in hygiene. Therefore, the toner and the developer can be repeatedly used for a long time and have a long life. Then, by dehydration and drying, powdery toner particles having an irregular shape can be obtained.

In the toner for developing an electrostatic image of the present invention, in order to further improve physical properties such as fluidity and chargeability, the above-mentioned silica fine powder, vinyl (co) polymer, and Fine particles of zinc stearate, aluminum oxide, titanium oxide and the like can be further added and mixed as a toner external additive. When these are added, they are preferably mixed in an amount of 0.05 to 5% by weight with respect to the toner before addition. The toner thus obtained can be mixed with a carrier to form a developer. There are no particular restrictions on the type of carrier,
Well-known materials such as iron oxide powder, various ferrites, and magnetite can be used. The mixing ratio of the toner and the carrier is not particularly limited, and a known mixing ratio can be used.
Generally, 1 to 10% by weight of toner is used in the developer. The electrostatic charge image developing toner and developer of the present invention can be used in various known developing means and fixing means.

[0031]

EXAMPLES The present invention will be described in detail below with reference to examples. Examples 1 to 12 (1) Production of polyester resin The acid component and alcohol component shown in Table 1 were charged into a reaction vessel, and the temperature was gradually raised while blowing nitrogen gas to 18
After advancing the condensation reaction at 0 ° C. for 5 hours, the temperature was raised to 230 ° C. to complete the reaction at the same temperature. The glass transition temperatures of the resins obtained are also shown in the table.

[0032]

[Table 1]

(2) Production of hydroxyapatite (inorganic dispersant) Hydroxyapatite used as an inorganic dispersant was produced by the following method. An aqueous solution in which 166 parts by weight of calcium chloride was dissolved was added dropwise to an aqueous solution in which 391 parts by weight of trisodium phosphate dodecahydrate and 13 parts by weight of sodium hydroxide were added and reacted at 20 to 30 ° C. to give hydroxyapatite 5 An aqueous solution containing wt% was obtained. By adjusting the stirring speed and temperature, the average particle diameter is 1.0, 1.5, 2.0, 3.
5% by weight of 0 and 4.0 μm various hydroxyapatite
An aqueous solution was prepared.

(3) Production of Toner A toner mother liquor was produced by dispersing the polyester resin, the colorant (pigment), the solvent and the additives shown in Tables 2 and 3 in a ball mill until the pigment particles became submicron. The toner mother liquor was granulated in a dispersion medium containing an inorganic dispersant shown in Table 2 by using a homogenizer so that the average particle size was in the range of 5 to 9 μm. Rotor speed is 15-2
It was adjusted in the range of 0 m / sec. Next, the solvent was distilled off under normal pressure to reduced pressure under the temperature condition that the temperature was lower than the boiling point of the solvent and the difference from the boiling point was 80 ° C. or less. When toluene is used as the solvent, the temperature is 50 to 70 ° C, and the degree of vacuum is 30 to 150.
mmHg, the temperature is 20 to 30 when methylene chloride is used.
When methyl ethyl ketone was used at a temperature of 50 ° C. and atmospheric pressure, 80% by weight of toluene was desolvated at a temperature of 50 to 70 ° C. and a reduced pressure of 30 to 150 mmHg. After cooling, 12N hydrochloric acid was added until the pH reached 2, the inorganic dispersant was washed off, washed with water, dried under reduced pressure, and classified to obtain a solid amorphous toner having an average particle size in the range of 4 to 8 μm. The amount of toluene remaining in the toner was measured by a gas chromatography method and found to be 0.01% by weight. Then, the obtained toner 10
The toner external additives shown in Table 2 were added to 0 part by weight, and mixed by stirring with a Henschel mixer.

[0035]

[Table 2]

[0036]

[Table 3]

(4) Evaluation In Examples 1 to 6, a developer comprising 5% by weight of toner and 95% by weight of a copper-zinc ferrite carrier coated with a fluororesin and having an average particle diameter of about 60 μm was used as an OPC photoreceptor. Examples 7 to 12 were carried out using a regular developing type copying machine SF-7300 (manufactured by Sharp Corporation), and copper-zinc ferrite coated with 5% by weight of toner and a silicone resin and having an average particle size of about 60 μm. A developer consisting of 95% by weight of carrier, RICOPY FT
Using -7570 (manufactured by Ricoh Co., Ltd.), continuous printing was performed in an environment of high temperature and high humidity of 40 ° C. and relative humidity of 80%, and the following characteristics were evaluated. The results are shown in Tables 4 and 5.

(A) Reproducibility of color tone: Mylar paper was printed, and the reproducibility of a color image was examined by an OHP (overhead projector), and evaluated according to the following criteria. Good: A chromatic color is expressed and an intermediate color is also expressed. Poor ... Chromatic color does not appear. (B) Image density, fog and resolution Image density and fog were measured using a Macbeth reflection densitometer RD514 type (manufactured by A division kollmorgen Corp.). It was visually judged whether or not it was resolved. (C) Toner scattering The presence or absence of toner scattering was visually determined. (D) Cleaning Property The transfer residual toner on the photoconductor that passed the cleaning process was transferred to a blank sheet of paper with Scotch tape (manufactured by Sumitomo 3M Ltd.), and measured with a Macbeth reflection densitometer RD514 type and compared with a blank.

[0039]

[Table 4]

[0040]

[Table 5]

Example 13 The toners of Examples 1, 2 and 3 in Table 2 were put into a Konica Digital Full Color 9028 (manufactured by Konica Corporation) whose charger and transfer machine were modified for regular development, and after adjusting the initial image. When printing was performed, intermediate colors were accurately reproduced and the image quality was good. Example 14 The average particle size was 6 in the same manner as in Example 1 except that the sodium dodecyldiphenyloxide disulfonate (Compound-1) was replaced with the compound-2 (sodium octadecyldiphenyloxide disulfonate).
As a result of obtaining an irregular toner having a size of μm and evaluating the performance, the color tone reproducibility is good in the initial stage, the image density is 1.3, and the fog is 0.0.
8, resolution 7.1, no toner scattering, cleanability 0 (good)
Met. After printing 100,000 pages, the color tone reproducibility was good, the image density was 1.1, the fog was 0.08, the resolution was 6.3, the toner was not scattered, and the cleaning property was 0 (good). The toner yield was 90% by weight.

Comparative Example 1 The binder resin, pigment and charge control agent of Example 1 were premixed with a Henschel mixer and then melt-kneaded with a biaxial kneader. Then, the cooled kneaded product was subjected to pin mill and jet mill to obtain an irregular toner having an average particle size of 8 μm, and 0.2% by weight of hydrophobic silica HDKH2000 / 4 (manufactured by Wacker Chemicals) was mixed with a Henschel mixer. As a result of evaluation as in Example 1, the color tone reproducibility was initially determined.
Poor, image density 1.2, fog 0.1, resolution 6.3, no toner scattering, cleanability 0 (good), but poor color reproducibility after printing 40,000 pages, image density 0.8, Fogging 0.
15, the resolution was 4.0, the toner was scattered, and the cleanability was 0 (good). Further, the yield of the toner was as low as 60% by weight with respect to the yield of the toner of the present invention of 80 to 90% by weight.

Comparative Example 2 Except that the aqueous solution containing the inorganic dispersant of Example 1 was changed to an aqueous solution in which hydroxypropylmethylcellulose (Metroze 90SH-10 1% by weight aqueous solution manufactured by Shin-Etsu Chemical Co., Ltd.) was dissolved. And average particle size is 6 μm
As a result of obtaining a true spherical toner of No. 1 and evaluating the performance, the color tone reproducibility is poor (light does not pass) in the initial stage, and the image density is 1.
0, fog 0.1, resolution 6.3, toner scattering, and cleanability 0 (good), which was not stable to the environment.
Poor color reproducibility (no light transmission) after printing 2,000 pages, image density 0.8, fog 0.2, resolution 4.0,
The toner was scattered and the cleaning property was 5 (poor). The yield of the toner was 20% by weight, which was extremely low compared to the yield of the toner of the present invention of 80 to 90% by weight.

Comparative Example 3 Evaluation was carried out in the same manner as in Example 1, except that the sodium dodecyldiphenyloxide disulfonate aqueous solution was changed to an aqueous solution containing 6 parts by weight of a 1% by weight sodium dodecylbenzenesulfonate aqueous solution.
In initial performance, color tone reproducibility is good, image density is 1.2, fog is 0.08, resolution is 7.1, toner is not scattered, and cleanability is 0.
It was (good), but after printing 70,000 pages, the image density was 0.
8, fogging 0.1, resolution 4.0, toner scattering, and cleaning property were poor.

Example 15 The toners of Examples 7, 8 and 9 in Table 2 were put into a Konica Digital Full Color 9028 (manufactured by Konica Corp.) in which a charger and a transfer machine were modified for regular development, and after adjusting an initial image. When printing was performed, intermediate colors were accurately reproduced and the image quality was good. Example 16 The average particle size was 6 in exactly the same manner as in Example 7 except that the sodium dodecyldiphenyloxide disulfonate (Compound-1) was replaced with the compound-2 (sodium octadecyldiphenyloxide disulfonate).
As a result of obtaining an irregular toner having a size of μm and evaluating the performance, the color tone reproducibility is good in the initial stage, the image density is 1.3, and the fog is 0.0.
8, resolution 7.1, no toner scattering, cleanability 0 (good)
Met. After printing 100,000 pages, the color tone reproducibility was good, the image density was 1.1, the fog was 0.08, the resolution was 6.3, the toner was not scattered, and the cleaning property was 0 (good). The toner yield was 90% by weight.

Comparative Example 4 The binder resin, pigment and charge control agent of Example 7 were premixed in a Henschel mixer and then melt-kneaded in a biaxial kneader. Then, the cooled kneaded product was subjected to pin mill and jet mill to obtain an irregular toner having an average particle size of 8 μm, and 0.2% by weight of hydrophobic silica HDKH2000 / 4 (manufactured by Wacker Chemicals) was mixed with a Henschel mixer. As a result of the same evaluation, the color reproducibility is poor in the initial stage, the image density is 1.2, the fog is 0.1, the resolution is 6.3, and the toner is scattered.
No, cleanability was 0 (good), but after 40,000 pages printed, color reproducibility was poor, image density was 0.8, fog was 0.15, resolution was 4.0, toner was scattered, and cleanability was 0 (good). Met. Further, the yield of the toner is 80 to 80% for the toner of the present invention.
It was as low as 60% by weight with respect to 90% by weight.

Comparative Example 5 Except that the aqueous solution containing the inorganic dispersant of Example 7 was changed to an aqueous solution in which hydroxypropylmethyl cellulose (Metronose 90SH-10 1% by weight aqueous solution manufactured by Shin-Etsu Chemical Co., Ltd.) was dissolved. And average particle size is 6 μm
As a result of obtaining a true spherical toner of No. 1 and evaluating the performance, the color tone reproducibility is poor (light does not pass) in the initial stage, and the image density is 1.
0, fog 0.1, resolution 6.3, toner scattering, and cleanability 0 (good), which was not stable to the environment.
Poor color reproducibility (no light transmission) after printing 2,000 pages, image density 0.8, fog 0.2, resolution 4.0,
The toner was scattered and the cleaning property was 5 (poor). The yield of the toner was 20% by weight, which was extremely low compared to the yield of the toner of the present invention of 80 to 90% by weight.

Comparative Example 6 Evaluation was made in the same manner as in Example 7 except that sodium dodecyldiphenyloxide disulfonate sodium was changed to an aqueous solution containing 6 parts by weight of an aqueous solution of 1% by weight sodium dodecylbenzenesulfonate, and the results showed that the initial performance was the same. Good color reproducibility, image density 1.2, fog 0.
08, resolution 7.1, no toner scattering, cleanability 0 (good), but after printing 70,000 pages, image density 0.8, fog 0.1, resolution 4.0, toner scattering, cleanability It was bad.

[0049]

As is apparent from the above results, the toner and developer for developing an electrostatic charge image of the present invention maintain excellent image quality for a very long period of time even under high temperature and high humidity working conditions. . Further, according to the method for producing a toner of the present invention, the above excellent toner can be obtained in a high yield.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Chiaki Okada 4-13-1, Higashimachi, Hitachi, Ibaraki Prefecture Hitachi Chemical Co., Ltd. Yamazaki Plant

Claims (6)

[Claims] 1. A liquid obtained by dissolving or dispersing a toner material containing a polyester resin and a colorant in a solvent in which the polyester resin can be dissolved, and an inorganic dispersant and a compound represented by the general formula (I): (In the formula, R represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, m and n are 0, 1 or 2, and m +
n is chosen to be at least 1, p and q are each 0 or 1 and p + q is chosen to be at least 1, r is p + q and A is Na, K or NH.
_A toner for developing an electrostatic charge image obtained by granulating in an aqueous medium containing a surfactant represented by ₄ ) and removing the solvent. 2. The average particle size of the inorganic dispersant is 0.7 to 5 μm.
The toner for developing an electrostatic charge image according to claim 1, which is m. 3. The toner for developing an electrostatic image according to claim 1, wherein the inorganic dispersant is tricalcium phosphate and / or hydroxyapatite. 4. A toner material containing a polyester resin and a colorant is dissolved or dispersed in a solvent in which the polyester resin can be dissolved, and then this is mixed with an inorganic dispersant and a compound represented by the general formula (I): (In the formula, R represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, m and n are 0, 1 or 2, and m +
n is selected to be at least 1, p and q are each 0 or 1 and p + q is at least 1, r is p + q, A is Na, K or NH ₄
In an aqueous medium containing a surfactant represented by the formula (1) to a particle having a predetermined particle diameter under high-speed shearing to form particles, and then removing the solvent. Production method. 5. The electrostatic charge according to claim 4, comprising the step of sufficiently removing the solvent within a range in which the particle shape of the granulated particles does not substantially change, and then removing the inorganic dispersant and the surfactant. Method for producing toner for image development. 6. A developer comprising the toner according to claim 1, 2 or 3 and a carrier.