JPS63198072A - Production of polymerized toner - Google Patents

Abstract

PURPOSE:To obtain a polymer toner sharp in particle size distribution and good in developability characteristics at a good yield by using a hardly water-soluble inorganic fine powder in a dispersion medium and a polar substance in a monomer composition and setting a specified surface tension between the composition and the dispersion medium. CONSTITUTION:The monomer composition containing the polymerizable monomer, the polar substance, and a colorant is polymerized in the dispersion medium containing the inorganic dispersant powder soluble in Bronsted acid and hardly soluble in water, and substantially no water-soluble surfactant, and having a pH of 2.5-6.0, or 7.1-11.0, and in this case, expression 1 shown on the right is satisfied, where A is the surface tension between the monomer composition except the colorant, and the dispersion medium, and B is that between the monomer composition except the colorant, and the ion-exchanged water, and the hardly water-soluble inorganic dispersant is further added into the polymerization system containing the monomer composition particles in the course of the polymerization of the monomer composition, thus permitting a toner sharp in the particle size distribution and superior in developability characteristics to be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a toner used in a method for visualizing a latent image.

Toners that visualize latent electrical and magnetic images, etc., are used in various processes for forming and recording images.

As one of such image forming processes, electrophotography, many methods are known, such as those described in US Pat. No. 2,297.691. This electrophotographic method generally uses a photoconductive substance to form an electrical latent image on a photoreceptor by various means, and then develops the latent image with toner to form a toner image. Then, if necessary, the toner image is transferred to a transfer material such as paper, and then the toner image is fixed to the transfer material using heat, pressure, solvent vapor, etc., thereby obtaining a copy. Furthermore, various methods have been proposed in the past as methods for developing using toner or methods for fixing toner images, and methods that involve passing through each image forming process have been adopted.

Conventionally, toners used for these purposes are generally prepared by melting and mixing a colorant made of a magnetic material or dye/pigment in a thermoplastic resin, uniformly dispersing the colorant, and then finely pulverizing the colorant.
By classifying toners, toners having a desired particle size have been manufactured.

According to this production method (pulverization method), a fairly good toner can be produced, but there are certain limitations, namely the range of selection of toner materials.For example, the resin colorant dispersion is sufficiently brittle, Due to this requirement, the resin colorant dispersion must be able to be finely pulverized using economically available production equipment, and the dispersion must actually be pulverized at high speed. When doing so, a problem arises in that a particle group with a wide particle size range is likely to be formed, and in particular, a relatively large proportion of excessively finely ground particles are included in this particle group. Furthermore, such a highly brittle material is susceptible to further pulverization or powdering when actually used for development in a copying machine or the like.

In addition, in this pulverization method, it is difficult to completely and uniformly disperse solid particles such as magnetic powder or colorant into the resin, and depending on the degree of dispersion of these fixed particles, fog may increase and image density may decrease. Careful attention must be paid to the extent of this dispersion, as it causes a decrease in
Exposure of the colorant to the fractured surface of the colored resin fine powder may cause variations in toner development characteristics.

On the other hand, in order to overcome the problems of toner produced by these pulverization methods, a method for producing toner using a suspension polymerization method has been proposed. In this suspension polymerization method, a monomer in which a polymerizable monomer and a coloring agent (in addition, a polymerization initiator, a crosslinking agent, a charge control agent, and other additives as necessary) are uniformly dissolved or dispersed is used. The composition is introduced into an aqueous phase (ie, continuous phase) containing a suspension stabilizer, and is granulated and polymerized with stirring to form toner particles.

This suspension polymerization method is a preferred toner manufacturing method because it does not include any pulverization process, does not require the toner material to be brittle, and does not expose the colorant to the toner fracture surface. The toner is spherical in shape and has various advantages such as excellent fluidity and uniform triboelectric charging properties. However, in this suspension polymerization, it is necessary to carry out the polymerization in a stable suspension system where the monomer composition particles do not coalesce, or to form fine polymer particles with a uniform particle size distribution by polymerization. Obtaining this is not always technically easy.

Not only toners obtained by this suspension polymerization method, but also toners used in methods for visualizing latent images, are required to control various properties in order to faithfully reproduce the original image. Among the properties, control of particle size distribution is one of the most important issues. In other words, when an image is formed using a toner that has a broad particle size distribution and contains a large amount of particles with a non-standard particle size, the sharpness of the image may be affected due to toner scattering, fogging, unevenness, etc. In addition, problems such as deterioration of toner durability arise due to variations in the development characteristics of the toner.

Conventionally, in this suspension polymerization method, various methods have been proposed in order to sharpen the particle size distribution of the toner. A method of adjusting the particle size by a combination of methods, a method of adjusting the particle size by adding an aqueous phase polymerization inhibitor as disclosed in JP-A-56-156839, etc. have been proposed, but a polymerized toner having a preferable particle size distribution has not yet been obtained. Not yet.

In particular, surfactants such as anionic surfactants are difficult to remove even by washing with water, and therefore tend to remain on the surface of toner particles, which has the drawback of easily causing a deterioration of toner development characteristics.

Generally, in the suspension polymerization method, a polymerizable monomer system that is substantially incompatible with the dispersion medium, typically water, is dispersed and polymerized to form toner particles. In order to obtain sharp polymerized toner particles, it is important to keep the droplets of the polymerizable monomer system (monomer composition particles) suspended in the liquid dispersion medium stable to a constant diameter during the polymerization process. An extremely important issue is how to maintain this level.

Conventionally, as a means to solve such problems, generally,
It has been attempted to lower the monomer composition (oil droplets)-dispersion medium interfacial tension by adding water-soluble surfactants to the dispersion medium.

However, when such a water-soluble surfactant is added, the formation of emulsion particles (particle size of 1μ or less) due to partial emulsification of the monomer composition is unavoidable. Because it had a strong tendency to remain on the surface,
The particle size distribution of the toner became broad, making it difficult to obtain a toner with good development characteristics.

On the other hand, when the above-mentioned water-soluble surfactant is not used, there is a strong tendency for coarse monomer composition particles to be formed due to insufficient reduction in interfacial tension, and coarse toner particles are generated.
The toner particle size distribution also tended to be broad.

Further, in such conventional polymerized toner production methods, coalescence of particles during polymerization is unavoidable, resulting in deviations in particle size distribution and a decrease in yield.

Due to the above-mentioned problems, there is a strong need for a toner production method that provides a toner with a sharp particle size distribution and good development characteristics in a high yield.

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner manufacturing method that solves the above-mentioned problems.

Another object of the present invention is to provide a method for producing a polymerized toner having a sharp particle size distribution with a high yield.

Still another object of the present invention is to provide a method for producing a polymerized toner with good development characteristics.

11 and 1 As a result of intensive research, the present inventors have found that combining a polar substance contained in a monomer composition and a specific poorly water-soluble inorganic dispersant powder is a suitable way to adjust the interfacial tension. It is possible to realize
Furthermore, it has been found that coalescence of toner particles can be effectively suppressed to provide a polymerized toner having a sharp particle size distribution and excellent development characteristics.

The method for producing a polymerized toner of the present invention is based on the above findings, and more specifically, it contains a poorly water-soluble inorganic dispersant powder that is soluble in Brønsted acid, and has a pH of 2.5 to 6.0.
Or, a monomer containing at least a polymerizable monomer, a polar substance, and a colorant in a dispersion medium that is in the range of 7.1 to 11.0 and does not substantially contain a water-soluble surfactant. A method for polymerizing a monomer composition, wherein the interfacial tension (A) between the monomer composition excluding the colorant and the dispersion medium is (represents the interfacial tension between the monomer composition minus the colorant and ion-exchanged water)
The present invention is characterized in that a poorly water-soluble inorganic dispersant is further added to the polymerization system containing the monomer composition particles during the polymerization of the monomer composition.

The functions of the toner manufacturing method of the present invention having the above configuration will be described below in comparison with the conventional method.

That is, in general, in the suspension polymerization method, a polymerizable monomer composition is added to a dispersion medium and dispersed by stirring, and when polymerization is carried out, stirring with a relatively high shear force is performed initially. From the viewpoint of efficient granulation and polymerization, it is preferable to obtain particles of a desired particle size, and then to stir relatively weakly to an extent that does not cause sedimentation of the particles to complete the polymerization.

However, in the conventional suspension polymerization method, even if the desired particle size and particle size distribution are obtained at the initial stage of polymerization by using an appropriate amount of dispersant, the viscosity of the particles increases as the polymerization progresses. It is presumed that because the particles tend to coalesce, the toner particles finally obtained have a particle size distribution that deviates from the desired particle size distribution, and the yield is also reduced.

On the other hand, in the production method of the present invention having the above configuration, a polar substance contained in the monomer composition and an inorganic substance soluble in Brønsted acid are used without using a water-soluble surfactant. A suitable interfacial tension between the monomer composition particles (droplets) and the dispersion medium is achieved through interaction with the dispersant. Therefore, according to the present invention, monomer composition particles having a fine particle size and a sharp particle size distribution substantially free of emulsion particles can be obtained.

Furthermore, (according to the findings of the present inventors) in such a dispersion system, the particle size and particle size distribution of particles are mostly determined by the initial dispersant and stirring conditions; for example, the amount of initial dispersant Increasing the amount of the initial dispersant will result in a smaller particle size, and decreasing the amount of initial dispersant will result in a larger particle size.

Therefore, according to the method of the present invention, a desired particle size distribution can be obtained by utilizing the interaction between the poorly water-soluble inorganic dispersant and the polar substance at the initial stage of polymerization (or before substantial polymerization starts). After that, during the polymerization process (for example, under weak stirring), the dispersion stability of the particles is further increased by adding a dispersant (effectively suppressing particle coalescence during the polymerization process due to increased viscosity, etc.), and improving the particle size distribution. It is possible to prevent misalignment and decrease in yield.

As a result, in the present invention, it is possible to obtain a toner that has a desired particle size and a sharp particle size distribution, and also has excellent development characteristics (by not using a water-soluble surfactant). Particle size and particle size distribution can be balanced with particle stability and toner yield.

Furthermore, according to the method of the present invention, it is possible to use a highly hydrophobic and poorly water-soluble polar substance (which was difficult to use in conventional methods) as the polar substance, and it has a sharp particle size distribution and development characteristics ( In particular, it becomes possible to form a toner with even better environmental properties.

The present invention will be explained in more detail below. In the following description, "1 part" and "1%" expressing quantitative ratios are based on weight unless otherwise specified.

In the production method of the present invention, the monomer composition containing at least a polymerizable monomer, a polar substance, and a colorant has an interfacial tension with this monomer composition within a specific range. Polymerized in a dispersion medium.

If the interfacial tension is (A) and the interfacial tension between the model composition and ion-exchanged water is (B), then in the present invention, it is necessary that the following is true, and it is preferable that the following is true.

If this value is less than 5, the decrease in interfacial tension obtained by the polar substance will be small, and the decrease in interfacial tension will be inhibited, resulting in the formation of an emulsion of the monomer composition, which is undesirable. The interfacial tension becomes relatively high, resulting in poor granulation properties.

In the present invention, a composition (model composition) obtained by removing the colorant (pigment, magnetic particles, etc.) from the monomer composition is used to measure the interfacial tensions (A) and (B).

According to the findings of the present inventors, even if such a model composition is used, measurement errors due to interfacial tension values (due to increased viscosity, etc.) that are virtually unchanged from those when the monomer composition itself is used. ) is preferable because it can eliminate such a model composition. Therefore, in the present invention, such a model composition is used for convenience in carrying out interfacial tension measurement.

It is necessary that the "model composition" contains at least a polymerizable monomer and a polar substance, but if necessary, among the various additives (interfacial It is preferable to contain a charge control agent (which is an additive that does not adversely affect tension measurement) and/or a crosslinking agent. Note that among the additives described below, low softening point compounds (such as paraffin) may cause errors in interfacial tension measurement (due to increased viscosity), so it is preferable not to include them in the model composition.

In the present invention, the preferable range of the above 1 interfacial tension (A) is 1
8 to 2 dyne/cm, and the preferable range of interfacial tension (B) is 22 to 3 dyne/cm.

In the present invention, the interfacial tensions (A) and (B) are measured by a surface tension measuring device (manufactured by Kyowa Kagaku Co., Ltd.),
YOWA CBVP 5surface Ten5lo
The value measured by a conventional method at room temperature (20 to 30° C.) using a n Meter^3) is used.

An outline of this interfacial tension measurement method is described below.

(1) Pour the dispersion medium (or ion-exchanged water) into a container that has been cleaned using a conventional method, and pour the glass detection plate (e.g.
(mm x 24 mm) completely immersed.

(2) Next, the polymerizable monomer composition (Sodel composition) is gently poured into the container and allowed to stand at room temperature for 30 minutes.

(3) Next, gently pull up the glass detection plate and measure the interfacial tension.

In the present invention, as the polar substance contained in the monomer, a substance having a polar group in the molecule and causing a decrease in interfacial tension at the interface between water and the polymerizable monomer system is used.

Further, the polar substance used in the present invention is preferably a poorly water-soluble substance from the viewpoint of improving the environmental characteristics of polymerized toner particles.

Here, the term "poorly water-soluble substance" refers to a substance that has a solubility of 1 g or less in 100 mfL of water, preferably 500 mg.
Hereinafter, those having a solubility of 100 mg or less are particularly preferred.

In the present invention, both low-molecular compounds and high-molecular compounds are used as such polar substances, but in the case of high-molecular compounds, the weight average molecular weight measured by GPC (gel permeation chromatography) is 5,000
500,000 is preferably used because it dissolves and disperses well in the polymerizable monomer and also imparts durability to the toner.

More specifically, anionic or cationic compounds as shown below are preferably used as this polar substance.

(1) Anionic compound A compound containing an anionic polar group such as a carboxyl group, hydroxyl group, dibasic acid group, dibasic acid anhydride group, sulfonic acid group, sulfonic acid group, phosphate ester group, etc.: More specifically, unsaturated carboxylic acids such as acrylic acid and methacrylic acid, unsaturated dibasic acids, anhydrides of unsaturated dibasic acids, and polymers of polar vinyl monomers such as acrylic esters and methacrylic esters having hydroxyl groups. Coalescence or copolymer; or copolymer of these polar vinyl monomers with styrene, acrylic ester, or methacrylic ester;
Polyester resin; Cyclized rubber: Chromium complex of alkyl-substituted salicylic acid; Isopropyl triisostearoyl titanate, Isopropyl tridecylbenzenesulfonyl titanate, Isopropyl tris (dioctyl pyrophosphate)
Titanate, Bis(dioctyl pyrophosphate) oxyacetate titanate, Bis(dioctyl pyrophosphate) ethylene titanate, Isobrobyl trioctaine titanate, Isopropyl dimethacrylylisostearoyl titanate, Isopropyl tri(dioctyl phosphate) titanate, Isopropyl tricumylphenyl titanate, Di Examples include titanate coupling agents such as milphenyloxyacetate titanate and diisostearoyl ethylene titanate.

(2) Cationic compound For example, a nitrogen-containing compound containing a basic polar group such as a -class amino group, a secondary amino group, or a tertiary amino group; specifically, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, etc. A polymer or copolymer of a nitrogen-containing monomer, a copolymer of styrene and the nitrogen-containing monomer, or a styrene, unsaturated carboxylic acid ester (e.g.
Copolymer of nitrogen-containing monomer with acrylic acid ester, methacrylic acid ester), etc.; isopropyl tri(N-aminoethyl-aminoethyl)
Examples include amino group-containing titanate coupling agents such as titanates.

Here, when the polar substance is an anionic polar polymer, it is preferable that the acid value and/or hydroxyl value is 0.5 to 100, and the amount added to 100 parts of the polymerizable monomer is 0. .1 to 50 parts is preferred.

Further, when the polar substance is a cationic polar polymer, the amine value is preferably 0.5 to 100, and
The amount added to 100 parts of the polymerizable monomer is 0.1 to 5
Preferably it is 0 parts.

If the acid value and/or hydroxyl value or amine value of the polar polymer used in the present invention is less than 0.5, the effect of lowering the interfacial tension will be small; on the other hand, if these values exceed 100,
It is undesirable because it is too hydrophilic.

Here, the acid value refers to the number of 1 g of potassium hydroxide required to neutralize the carboxyl groups contained in 1 g of the sample.

The hydroxyl value refers to the number of 1 g of potassium hydroxide required to neutralize acetic acid bonded to hydroxyl groups when 1 g of a sample is acetylated by a specified method.

In addition, the amine value refers to the number of 1 g of potassium hydroxide required to neutralize the hydrochloric acid required to neutralize 1 g of the sample.

As mentioned above, a polar substance having surface activity that dissolves and disperses in the polymerizable monomer is added to the monomer composition as an additive.
For example, a preferred polymerized toner can be obtained by adding a polar polymer, a polar copolymer, a cyclized rubber, or a polyester to polymerize the polymerizable monomer. These polar polymers, polar copolymers or cyclized rubbers contain 100% of the polymerizable monomer
0.1 to 50 parts by weight, preferably 1 to 4 parts by weight
It is better to add 0 parts by weight, and in the end groove of 0.1 parts by weight,
It is difficult to obtain a sufficient pseudocapsule structure, and if 50 parts by weight is added, the amount of polymerizable monomer becomes insufficient and the properties as a polymerized toner tend to deteriorate. It is preferable that a polymerizable monomer composition containing a polar polymer, a polar copolymer, a cyclized rubber, etc. is suspended in an aqueous phase of an aqueous medium in which a fine powder dispersion stabilizer is dispersed, and then polymerized. .

In this case, the added polar polymer, polar copolymer, cyclized rubber, or polyester gathers on the surface layer of the toner particles, forming a kind of shell-like shape, and the resulting particles have a pseudo-capsule structure. It becomes like having. The relatively high molecular weight polar polymer, polar copolymer, or cyclized rubber that gathers on the surface layer of the particles gives the toner anti-blocking properties.
Provides excellent properties such as developability, charge controllability, and abrasion resistance.

On the other hand, the poorly water-soluble inorganic dispersant that is soluble in Bronsted acid and used in the present invention is a poorly water-soluble inorganic compound that is soluble in Bronsted acid (more specifically, in water 100+ljZ). 20g or more).

Here, the poorly water-soluble inorganic compound is 10 μg or less (preferably 5 m
(g or less).

Examples of poorly water-soluble inorganic dispersants used in the present invention are shown below.

(1) Inorganic compounds that are neutral or alkaline in water, such as calcium phosphate, magnesium phosphate,
Calcium sulfate, magnesium carbonate, calcium carbonate, Cas(PO4)z”Ca(OH)2, etc.

(2) Inorganic compounds that are acidic in water, such as inorganic compounds containing amphoteric elements (elements that produce amphoteric oxides) such as aluminum phosphate, zinc phosphate, and zinc carbonate.

The particle size of such an inorganic compound is preferably 2 μm or less, more preferably 1 μm or less in terms of primary particles.

The particle size of the poorly water-soluble inorganic dispersant mentioned above in the dispersion medium is
Measured by Coulter Counter.

That is, a sample (inorganic compound) was added to a 1% saline solution to a concentration of approximately 10%, and after 41 minutes of ultrasonication ((36 KHz, 100 W, 1 minute)) using a conventional method,
Measurement is carried out using a Coulter counter using a 0 μ■ orifice in the usual manner.

In the number distribution of inorganic dispersants measured by this method, the proportion of particles with a particle size of 5.04 μm or more is 5.
% or less, and it is more preferable that the proportion of particles having a particle size of 3.17 μm or more is 5% or less in number.

These inorganic dispersants may be used as they are in the form of powdered inorganic compounds, but a method in which a poorly soluble inorganic compound is generated in water using substances such as sodium phosphate and calcium chloride and then used as is is in the form of fine particles. This is preferred because an inorganic compound with good dispersibility can be easily obtained.

In general, the aggregation of powdered poorly soluble inorganic compounds is generally a strong agglomeration state, and the particle size that causes this aggregation state is also non-uniform, so when such powders are used, it is difficult to disperse them in water. In many cases, it is necessary to carry out the process carefully. However, if the method of generating poorly soluble inorganic compounds in water as described above is used, there is no such concern and a good dispersion state of the inorganic compounds can be easily obtained. .

Furthermore, when a poorly water-soluble compound is produced in water in this way, the water-soluble neutral salts obtained together with the poorly soluble compound have the effect of preventing the dissolution of 1,000 ml in water and increasing the specific gravity of water. It has both effects.

Examples of reactions that produce poorly soluble inorganic compounds are shown below, but the reaction is not limited thereto.

2 N a s P O4+ 3 CM C112m
Ca @ (PO4) Yi+6NaCj! 2 N a s P O4+ 3 M g S Oa
-M g 5(PO4)z +3Na25O4 2Nas po4+Au2 (304)s -2Aj
EP O4+ 3 N a 2 S OaNa2So4
+CaCJZ, mcaso, +Na25o Na 2 COs + M g SO4-M g
COs + Na25o.

N a 2 COs + Ca C41! -CaCO
S +2NaCJl 2Na3 PO4 + 3ZnSO4mZn.

(P Oa ) * + 3 N a 2 S O4N
a 2 COs + Z n CJl 2- Z n
CO@ +2NaCi Na 2 COs + Z n SO4-Z n
CO@+Na25o.

In the present invention, the pH of the dispersion medium containing the above-mentioned poorly water-soluble inorganic dispersant is set to 2.5 to 6.0, or 7.0 to 6.0.
1 to 11.0.

When the pH is <2.5 or >11.0, the acidity or alkalinity of the dispersion medium becomes too strong, resulting in insufficient granulation of the monomer composition.

On the other hand, the pi of the dispersion medium is 6. t<pi+<'r
, 1, the interfacial tension between the monomer and the surface of the composition is insufficiently lowered.

In addition, when adjusting the pH in this way, a water-soluble inorganic salt exhibiting alkalinity, a water-soluble inorganic salt exhibiting alkalinity,
Alternatively, it is preferable to adjust the pH by adding a water-soluble inorganic salt exhibiting acidity to create a dispersion medium that promotes the surface activity of polar substances.

Examples of water-soluble inorganic salts exhibiting alkalinity used in such cases include Na=po4. Na2COs, Na
OH%KO) 1st grade.

In addition, water-soluble inorganic salts exhibiting acidity include Mg5o,
, CaCj! 2, ZnSO4, AfLK (S04)
z s Aj! *(S04)s, ZnCj!
There are z etc.

In this method, two or more types of water-soluble inorganic salts may be used in combination, if necessary.

In the above, polar substances (surface-active substances) and poorly water-soluble inorganic dispersants have been explained. Preferred combinations of these are illustrated below, but the invention is not limited to these exemplified combinations.

(A) A combination of an anionic compound (1) and a poorly water-soluble inorganic dispersant (1) that is neutral or alkaline in water, (B) a combination of a cationic compound (2) and a poorly water-soluble inorganic dispersant that is acidic in water. Combination with inorganic dispersant (2).

In the above combination (A), it is more preferable to add a water-soluble inorganic salt exhibiting alkalinity to adjust the pH.

Further, in the above combination (B), it is more preferable to add a water-soluble inorganic salt exhibiting acidity to adjust the pH.

Furthermore, in the above method, if necessary, 2f! of a poorly water-soluble inorganic dispersant is added. The above may be used in combination.

In the present invention, a dispersion medium that is substantially incompatible with the polymerizable monomer is used, and it is preferable to use an aqueous dispersion medium.

In the present invention, as the dispersion medium containing the poorly water-soluble inorganic dispersant, one that does not substantially contain a commonly known water-soluble surfactant is used. In the present invention, the water-soluble surfactant is For 100 parts of inorganic dispersant powder, o,
Although it is possible to use it in an amount less than oot parts by weight,
There is no problem even if no water-soluble surfactant is used.

In the production method of the present invention, during the polymerization of the monomer composition (that is, after the granulation of the monomer composition is substantially completed by stirring with high shear force, etc., until the end of the polymerization reaction) ), a polymerization system comprising monomer composition particles and a dispersion medium;
It is sufficient to further add a poorly water-soluble inorganic dispersant, but from the viewpoint of increasing the effect of suppressing particle coalescence during the polymerization process, it is preferable to add the inorganic dispersant immediately after the granulation of the monomer composition is substantially completed. It is preferable to add.

The amount (b) of the dispersant added during the polymerization (for example, during weak stirring) can be determined as desired relative to the amount (a) of the dispersant used during granulation or at the initial stage of polymerization (for example, during high-shear stirring). Although it is possible to set the ratio as a+b 100 (parts), preferably a: b-50: 50 to 95:5 (
Department).

The dispersing agent added during polymerization may be the same type as the dispersing agent used during granulation or at the initial stage of polymerization, or may be different from the dispersing agent used in (1) or (1) above.
It is preferable to select from within the same group (2), and the number of additions may be two or more.

The method of the present invention, in which a dispersant is added during polymerization, lowers the polymerization temperature to slow down the decomposition of the polymerization initiator in order to adjust the molecular weight distribution (particularly from the viewpoint of fixing properties). This is a particularly preferred method when using a polymerization method in which the time required for coalescence (due to increased viscosity accompanying polymerization) to easily occur is relatively long.

In such a case, the temperature of the mold car is such that the half-life of the polymerization initiator is S.
The temperature is preferably 00 minutes or more (more preferably 1000 minutes or more).

In such a polymerization method, after the dispersibility of the particles is stabilized, the polymerization temperature is raised to produce a polymer with a smaller molecular weight, and the ratio of the weight average molecular weight to the number average molecular weight (M w / It is also possible to adopt a method of increasing M n ).

In the present invention, when the monomer composition is granulated in an aqueous dispersion medium, it is granulated using, for example, a homomixer or homogenizer having a turbine and a stator that rotate at high speed. In general, it is preferable to adjust the stirring speed and time so that the monomer composition particles have a size of 30μ■ or less.The zero rotation speed is when the circumferential speed of the turbine is 10 to 30 rr.
It is preferable to use it so that it becomes r/sec, and the granulation time is not particularly limited, but is preferably 5 to 60 minutes.

When the liquid temperature during the granulation step is adjusted to a temperature at which the monomer composition has a viscosity of 1 to 100,000 cps, preferably 100,000 to 100,000 cps, the particle size of the monomer composition particles can be adjusted to 1 to 10 μm. The final weight average particle size is 1 to 10 μm.
A toner for development can be produced. As the liquid dispersion medium, water or an aqueous medium containing water as the main component is usually used.
The liquid temperature of the dispersion liquid is 20 to 80°C (even 40 to 70°C)
It is preferable that it is adjusted to.

In the dispersion liquid, it is preferable that the liquid dispersion medium is present in an amount of 200 to 1000 parts by weight based on 100 parts by weight of the monomer composition, and the slightly water-soluble inorganic dispersant is used for polymerization (at the time of granulation or early stage of polymerization). It is preferably used in an amount of 1 to 20% by weight (more preferably 1 to 4% by weight) based on the weight of the monomer composition.

Next, each component constituting the monomer composition will be explained.

Polymerizable monomers used in the present invention include CM, -, i.e., styrene, 0-methylstyrene, m-
Methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene,
3.4-dichlorostyrene, p-ethylstyrene, 2.
4-dimethylstyrene, p-n-butylstyrene, P-
Styrene and its derivatives such as tert-butylstyrene, p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, P-n-decylstyrene, p-n-dodecylstyrene: ethylene, Ethylenically unsaturated olefins such as propylene, butylene, and isobutylene; Vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide, and vinyl fluoride; Vinyl esters such as vinyl acetate, vinyl propionate, and vinyl benzene chloride Methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, methacrylic acid α-methylene aliphatic monocarboxylic acid esters such as dimethylaminoethyl and diethylaminoethyl methacrylate; methyl acrylics, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, acrylic Acrylic acid esters such as dodecyl acid, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, and phenyl acrylate; maleic acid, maleic acid hafester; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, and vinyl isobutyl ether. Vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, and methyl isopropenyl ketone; N-vinyl compounds such as N-vinyl pyrrole, N-vinyl carbazole, N-vinylindole, and N-vinyl pyrrolidone; vinyl naphthalene series acrylonitrile; Examples include acrylic acid or methacrylic acid derivatives such as methacrylonitrile and acrylamide. These ingredients can be used alone or in combination. Among the above-mentioned monomers, it is preferable to use styrene or a styrene conductor alone or in combination with other monomers as a polymerizable monomer in terms of the development characteristics and durability of the toner.

In order to improve the fixing properties and anti-offset properties in hot pressure roller fixing, the monomer composition contains release properties such as waxes such as paraffin wax, and low molecular weight polyolefins such as low molecular weight polyethylene and low molecular weight polypropylene. (preferably a softening point of 50
In this case, the amount of the low softening point compound added is 1 to 300 parts by weight per 100 parts by weight of the polymerizable monomer. Parts by weight are preferred.

The above-mentioned low softening point compounds include paraffin, wax,
Low molecular weight polyolefins, modified waxes having aromatic groups, hydrocarbon compounds having alicyclic groups, natural waxes, long chain hydrocarbons mR (CHl (CHl
:) tt or -(CH2) 12 or more aliphatic carbon chains]
Examples include long-chain carboxylic acids having the following and esters thereof. A mixture of different low softening point compounds may be used.

Specifically, the low softening point compounds include paraffin wax (manufactured by Nippon Oil), paraffin wax (manufactured by Nippon Seiro), microwax (manufactured by Nippon Oil), microcrystalline wax (manufactured by Nippon Seiro), Hard paraffin wax (manufactured by Nippon Seiro), PE-130 (manufactured by Hoechst),
Mitsui Hiwax 110P (Mitsui Petrochemical), Mitsui Hiwax 220P (Mitsui Petrochemical), Mitsui Hiwax 660P (Mitsui Petrochemical), Mitsui Hiwax 210P (Mitsui Petrochemical), Mitsui Hiwax 32
0P (Mitsui Petrochemical), Mitsui Hiwax 410P
(manufactured by Mitsui Petrochemicals), Mitsui Hiwax 420P (manufactured by Mitsui Petrochemicals), modified wax JC-1141 (manufactured by Mitsui Petrochemicals), modified wax JC-2130 (manufactured by Mitsui Petrochemicals), modified wax JC-4020 (manufactured by Mitsui Petrochemicals) Chemicals), modified wax JC-1142 (Mitsui Petrochemicals),
Modified wax JC-5020 (manufactured by Mitsui Petrochemicals); Examples include beeswax, carnauba wax, and montan wax.

In the monomer composition, in order to generate a crosslinked polymer,
Suspension polymerization may be carried out in the presence of a crosslinking agent, especially if no polymer, copolymer or cyclized rubber is added to the monomer composition. It is preferable to add it.

Examples of the crosslinking agent include divinylbenzene, divinylnaphthalene, polyethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, 1.3-butylene glycol dimethacrylate, 1.6-hexane gelicold dimethacrylate, and neopentyl. Glycol dimethacrylate, dipropylene glycol dimethacrylate, polypropylene glycol dimethacrylate, 2.2'-
Bis(4-methacryloxyjethoxyphenyl)propane, 2,2'-bis(4-acryloxyjethoxyphenyl)propane, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, tetramethylolmethanetetraacrylate, dibromoneo General crosslinking agents such as pentyl glycol dimethacrylate and diallyl phthalate can be used as appropriate (two or more types in combination as necessary).

If these crosslinking agents are used in large amounts, the toner becomes difficult to melt with heat, resulting in poor heat fixing properties or heat pressure fixing properties. In addition, if the amount used is small, properties such as processing resistance and durability necessary for toner will deteriorate, and during hot roll fixing, some of the toner will not be completely fixed to the paper and will stick to the roller surface, causing the toner to be attached to the next paper. It becomes difficult to prevent the offset phenomenon of metastasis. Therefore, the amount of these crosslinking agents used is preferably o,oot to 15% by weight (more preferably 0.1 to 10% by weight) based on the polymerizable monomer.

The monomer composition contains a live coloring agent, and dyes and pigments or magnetic particles are preferably used as this coloring agent.

As dyes and pigments, conventionally known dyes, carbon black, and pigments such as grafted carbon black in which the surface of carbon black is coated with resin can be used (if necessary, in combination of 2F! or more). . Such dyes and pigments are contained in an amount of 0.1 to 30% based on the polymerizable monomer.

Charge control agents and fluidity modifiers may be added (internally added) to the toner as necessary, but when they are added internally,
The charge control agent and the fluidity modifier may be added to the monomer composition, but the charge control agent and the fluidity modifier may be used by being mixed (externally added) with the toner particles.

Examples of charge control agents include metal complexes of organic compounds having carboxyl groups or nitrogen-containing groups, metal-containing dyes, and nigrosine. Examples of fluidity modifiers or cleaning aids for the surface of the latent image carrier (photoreceptor) include colloidal silica and fatty acid metal salts. In addition, fillers such as calcium carbonate and finely powdered silica may be added to the toner in a range of 0.5 to 20% by weight for the purpose of increasing the amount.Furthermore, it prevents toner particles from coagulating with each other and improves fluidity. To do this, a flow improver such as Teflon fine powder or zinc stearate powder may be incorporated into the toner.

To produce a magnetic polymerized toner, magnetic particles may be added to the monomer composition. In this case, the magnetic particles also serve as a colorant (in whole or in part). As magnetic particles, substances that are magnetized when placed in a magnetic field are used, such as powders of ferromagnetic metals such as iron, cobalt, and nickel, or powders of alloys and compounds such as magnetite, hematite, and ferrite. Magnetic fine particles having a particle size of 0.05 to 5 μm, preferably 0.1 to 1 μm are used. When producing a toner with a small particle size (particle size of 8μ or less), it is preferable to use magnetic particles with a particle size of 0.8μ or less.The content of the magnetic particles is 100 parts of the monomer composition. 10 to 60 parts (and even 2 parts)
0 to 50 parts), and these magnetic fine particles may be treated with a treatment agent such as a silane coupling agent, a titanium coupling agent, or an appropriate reactive resin. Although it depends on the surface area of the magnetic fine particles and the density of hydroxyl groups present on the surface, a treatment amount of 5 parts or less (preferably 0.1 to 3 parts) per 100 parts of the magnetic particles is sufficient to produce a polymerizable monomer. The dispersibility of the toner particles is obtained, and the toner physical properties are not adversely affected.Also, lipophilic magnetic particles and lignophilic magnetic particles may be used as a mixture.

According to the findings of the present inventors, when a water-soluble polymerization initiator is used, the moisture resistance of the produced polymerized toner decreases, and the development characteristics and blocking resistance at high temperatures deteriorate. In order to produce a polymerized toner with excellent environmental properties, it is preferable to use a substantially water-insoluble polymerization initiator.

As mentioned above, the polymerization initiator used in the present invention is preferably substantially water-insoluble. In the present invention, a substantially water-insoluble polymerization initiator refers to a polymerization initiator that is substantially water-insoluble at room temperature. It has a solubility of 1 g or less per 100 g of water, preferably 0.5 g or less per 100 g of water, particularly preferably 1 g of water per 100 g of water.
It has a low solubility of 0.2g or less per 00g.

If the solubility exceeds 1 g per 100 g of water, it is not preferable because the decomposition products of the polymerization initiator remaining on the surface of the polymerized toner particles after completion of polymerization reduce the moisture resistance of the polymerized toner. The polymerization initiator used in
(1 to 10 parts by weight of the polymerization initiator per 100 parts by weight of the monomer) preferably has solubility characteristics that allow it to dissolve well in the polymerizable monomer.

As such a polymerization initiator, 2,2'-azobis(
2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis-
Azo or diazo polymerization initiators such as 4-methoxy-2゜4-dimethylvaleronitrile and other azobisisobutyronitrile (AIBN); benzoyl peroxide, methyl ethyl ketone peroxide, isopropyl peroxy carbonate, cumene hydroper Examples include peroxide-based polymerization initiators such as oxide, 2,4-dichlorylbenzoyl peroxide, and lauroyl peroxide.

Furthermore, it is also preferable to use a mixture of two or more types of polymerization initiators for the purpose of adjusting the molecular weight and molecular weight distribution of the polymer, or for the purpose of adjusting the reaction time.

The amount of the polymerization initiator used is 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the polymerized monomer. ! ! If the amount of polymerization initiator used is less than 0.1 part by weight, it is difficult to disperse or apply a sufficient amount of polymerization initiator evenly to each monomer composition particle, and if it is 201 parts by weight or more, it is too large. As a result, the molecular weight of the polymerization product becomes too low, and the tendency for the polymerization reaction to occur non-uniformly increases.

Such a polymerization initiator can be added to a dispersion system containing monomer composition particles after granulating the monomer composition, but it is possible to add the polymerization initiator to a dispersion system containing monomer composition particles evenly. From the viewpoint of dispersing or applying the initiator, it is preferable to include it in the monomer composition before granulation.

The suspension polymerization reaction is usually carried out at a polymerization temperature of 50° C. or higher, and the upper limit temperature is set in consideration of the decomposition rate of the polymerization initiator. If the set polymerization temperature is too high, the polymerization initiator will be rapidly decomposed, which is not preferable.

In the present invention, after confirming that the formed monomer composition particles have a predetermined particle size, polymerization is carried out by adjusting the liquid temperature (for example, 55 to 70°C) of the aqueous medium containing the particles. A method for advancing the reaction, or a method for advancing polymerization simultaneously with granulation and dispersion by adjusting the liquid temperature of the dispersion medium is used.

After the polymerization reaction of the monomer composition is completed, polymerized toner particles can be obtained by post-treatment using a conventional method. After removing the dispersant stabilizer, the polymer particles are recovered by a suitable method such as filtration, decantation, centrifugation, etc. and dried to obtain a polymerized toner.

The Brønsted acid-soluble poorly water-soluble inorganic dispersant used in the present invention can be easily removed from the toner particle surface by the above-mentioned acid (or alkali) treatment.

In the toner from which the dispersant has been removed in this way, there is no adverse effect of hydrophilicization of the toner surface (due to the residual dispersant), and good toner development characteristics can be obtained.

The polymerized toner obtained by the production method of the present invention can be applied to known dry electrostatic image development methods, such as cascade method,
Two-component development methods such as magnetic brush method, microtoning method, two-component AC bias development method; conductive-component development method;
One-component development methods using magnetic toner, such as insulating-component development method and jumping development method; powder cloud method and fur brush method; toner is transported to the developing section by being held on the toner carrier by electrostatic force It is applicable to a non-magnetic component development method in which the toner is transported to a developing section and subjected to development; and an electric field curtain development method in which the toner is transported to a developing section and subjected to development.

The toner obtained by the method of the present invention can be particularly preferably applied to a developing method using a small particle size toner having a weight average particle size of about 2 to 8 μm, which requires a sharp particle size distribution.

As described above, according to the method for producing a polymerized toner of the present invention, a poorly water-soluble inorganic fine powder in a dispersion medium and a polar substance in a monomer composition are used to disperse the composition/dispersion. By achieving a preferable interfacial tension between the media, monomer composition particles can be formed in a suitable state, and inorganic fine powder can be further added to the polymerization system during polymerization to prevent particle coalescence during the polymerization process. By suppressing this, a polymerized toner with a sharp particle size distribution and good development characteristics can be obtained in good yield.

Hereinafter, the present invention will be explained in more detail based on Examples.

Ion exchange water 1000+4! Inside, Na, PO4/12
25.5 g of H20 was added and stirred at 10,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo). C
aCj! 2 ・2H,O 14.2g ion exchange water 20
An aqueous solution dissolved at 0 mA was added to the above Na, PO, solution,
Gradually add the dispersion medium (pH -1
0.5) was obtained. When measured with a coulter counter, the particle size was 4.0 μm in the number distribution of the fine powder mentioned above.
The proportion of the above particles was 1% or less in number.

A monomer composition (viscosity at 60°C of 300 cps) was prepared by mixing at 60°C.

The monomer composition obtained above was placed in a stainless steel container with a capacity of 2 ft containing the dispersion medium containing calcium phosphate prepared as described above, and a homomixer ( 10. OO
The monomer composition was granulated by stirring at Orpm for 30 minutes.

Then, while stirring with a paddle stirring blade, 2.55 g of sodium phosphate hydrate (Nas PO4.12H20) and 1.42 g of calcium chloride hydrate (CaC12.2H20) were added.
50 g of a dispersion medium containing calcium phosphate prepared by adding 50 g of calcium phosphate to 50 g of ion-exchanged water was added, and polymerization was carried out at 50° C. for 6 hours and then at 80° C. for 4 hours while stirring.

After the above reaction is completed, the reaction product is cooled, dehydrated, and hydrochloric acid (
1/ION), further washed with water, dehydrated, and dried to obtain a polymerized toner. When the particle size of the obtained toner was measured with a Coulter counter (aperture diameter 100 μm), the volume average diameter was 8.5 μl, and the particle size was 16 μl.
．． The proportion of coarse powder of 0 μm or more in the volume distribution was 3%, which was an extremely narrow particle size distribution.

15 g of the toner obtained above and an average particle size of 50 μm
85 g of insulating carrier (composed of triiron tetroxide and epoxy resin), 0.75 g of hydrophobic silica (Aerosil R972, manufactured by Nippon Aerosil Co., Ltd.), and 0.45 g of zinc stearate powder were mixed to form a developer. was prepared, and its electrophotographic properties were evaluated under the following conditions.

A developing device whose schematic cross-sectional view is shown in the drawing was used as a developing device.

The image carrier 1 has a selenium photoreceptor 11, the peripheral speed of the image carrier 1 is 100 tan/sec, and the highest potential of the electrostatic image formed on the image carrier 1 is +750V.

The outer diameter of the sleeve (developer carrier) 2 is 20■■, its peripheral speed is 100■Il/sec, the N of the magnetic roller 3,
The magnetic flux density in the vertical direction of the sleeve surface of the S pole is 1000 Gauss, the thickness of the developer layer is 200 μm, the distance between sleeve 2 and image carrier 1 is 11 jl 300 μm, and the bias voltage applied to the sleeve is DC voltage component +200 V. When development was carried out at 1400 Vpp with an AC voltage component of 3.0 Hz, the electrostatic latent image on the image carrier 1 was developed well.

The toner image formed by this development is electrostatically transferred onto plain paper, and the toner image on the plain paper is transferred to a heat-pressure roller fixing device (7) consisting of a fixing roller having a silicone rubber surface layer and a pressure roller. Under pressure of g/cm', nip width 9
When the toner image was fixed at a fixing temperature of 150° C. (fixing roller surface temperature), this toner image was well fixed. The obtained fixed image has no fog and has an image density (Dmax) of 1
．． It showed 44.

In addition, in development 1 in the drawing, external additives (silica powder, etc.)
The toner T having the following properties is quantitatively supplied to the lower chamber by the supply roller 4 and the elastic member 5, and is mixed with the carrier to form the developer 6. A DC bias is applied from a DC bias power source 8 to the sleeve 2 containing the magnet roller 3 and the doctor blade.
AC bias is applied from an AC bias power supply 9. As the sleeve 2 rotates in the entry direction, the developer 6 is conveyed to the aluminum cylinder 12 and the selenium photoreceptor 11.
The electrostatic latent image on the image bearing member 1 is developed. The developer layer regulating member 10 also serves as an outer wall of the developing device.

In addition, 90 g of styrene, 10 g of 2-ethylhexyl methacrylate, 10 g of cyclized rubber, and Bontron E-81.
, 2g of NK ester 2G and 51g of NK ester 2G, the interfacial tension (interfacial tension (A)) with respect to the dispersion medium containing calcium phosphate prepared above (interfacial tension (A)) was measured using a surface tension measuring device (yow) using the method described above. ^、CBVP
It was measured at room temperature (25° C.) using a 5 surface Tension Meter^3).

This interfacial tension (A) was 2.0 dyne/cm.

On the other hand, when the interfacial tension (B) of the above model composition with respect to ion-exchanged water was similarly measured, it was found to be 3°2 dyne.
/cm.

Husband J1. (treated with 3 parts of BlenAct KR-1385 manufactured by Suso Co., Ltd.) The above polymerizable monomer mixture was treated with 60%
The monomer composition (viscosity at 60°C: 60
0 cps) was prepared.

In a stainless steel container with a capacity of 21, the monomer composition obtained above was added to a dispersion medium containing calcium phosphate prepared in the same manner as in Example 1, and TK was carried out at 50°C under an N2 atmosphere.
10,0OO using a homo mixer (Special Machinery Industry)
The mixture was stirred and granulated using rp+* for 30 minutes. After that, Example 1
Inorganic fine powder was added in the same manner as in Example 1, and a monomer composition was polymerized in the same manner as in Example 1.

The above reaction product was cooled, dehydrated, and hydrochloric acid (1/1 ON)
A polymerized toner was obtained by washing with water, dehydration, and drying. When the particle size of the obtained toner was measured using a Coulter Counter (Avachair diameter: 100 μm), the volume average diameter was 9.5 μm, and the proportion of coarse powder of 16 g or more in the volume distribution was 3% by volume, which is extremely small. The distribution was narrow.

0.6 g of hydrophobic silica (Talanox-500, manufactured by Talco) was mixed with 100 g of the toner obtained above.
A developer was prepared.

When this developer was used in a Canon copier NP-7550 and an image formation test (image formation test) was conducted at room temperature (25°C, 60%), images with good image quality and density were obtained. .

When images were produced in the same manner as above at 32.5°C and 90% high temperature and high humidity, images with good quality and density were obtained.

Na3PO4 hydrated salt (N
As PO4' 12H20) 30.8g was added and T
10.0 using K homo mixer (Special Machinery Industry)
Stirred in OOrp grave.

Al1 (SO4)s hydrated salt (Aj!z (SO4
), ・50% content) 29g of ion-exchanged water 200g
An aqueous solution dissolved in Naspo was gradually added to the Naspo solution while stirring with the homomixer, and a dispersion medium containing aluminum phosphate (pH -3, 8), which is a poorly water-soluble inorganic fine powder,
) was obtained.

When the particle size of the fine powder in this dispersion medium was measured using a Coulter counter, the proportion of particles with a particle size of 4.0 μm or more was 1% in number.

The above polymerizable monomer mixture was mixed with 6 ml using an attritor.
By mixing at 0°C, the monomer composition (viscosity at 50°C: 30
0 cps) was prepared.

The above monomer composition was placed in a stainless steel container with a capacity of 2 IL containing the dispersion medium containing aluminum phosphate prepared above, and the monomer composition was granulated in the same manner as in Example 1. Salt 6.1 and 6 g of aluminum mesulfate hydrate (5.8 g) were added to the above dispersion medium, and polymerization was carried out at 50° C. for 7 hours and then at 80° C. for 3 hours while stirring with a paddle stirring blade. Thereafter, the toner was processed in the same manner as in Example 1 to obtain a toner having a volume average diameter of a and Oμl.

A developer was prepared by mixing 6 g of hydrophobic silica treated with amino-modified silicone oil to 100 g of the toner obtained above. Use this developer on a Canon copier NP-35.
When image printing was carried out using No. 25, images with good image quality and density were obtained at room temperature. Also,
Even at a high temperature of 90% at 32.5° C., similarly good images were obtained.

L Gohan 1 Na, Cos anhydrous salt (N
8.91 g of C03) was added, and the mixture was stirred at 10,000 rpm using a TK homo mixer (manufactured by Tokushu Kika Kogyo). ZnCj! 2 anhydrous salt (ZnCIL*) in 11.
3g ion exchange water 200mj! was gradually added to the Nap Co@ solution while stirring with the homomixer to obtain a dispersion medium (pH=about 7.5) containing ZnCO3. When measured using a Coulter counter, the volume average diameter of the above ZnC0° was 2.9μ■, and the particle size was 4. O
The proportion of particles of μ- or more was 1% or less in number.

Using the dispersion medium containing ZnC0 obtained above and the monomer composition of Example 2, granulation was carried out in the same manner as in Example 2 at 45° C. under N atmosphere. Thereafter, while stirring with a paddle stirring blade, 50 g of a dispersion medium containing zinc carbonate prepared by adding 1.78 g of sodium phosphate hydrate and 2.26 g of zinc chloride hydrate into 50 g of ion-exchanged water was added, and the above Polymerization was carried out at 50°C for 6 hours and at 70°C for 4 hours while stirring.

Thereafter, a polymerized toner was obtained in the same manner as in Example 2.

When the particle size of the obtained toner was measured using a Coulter counter, it was found to be 8.5 μm in volume average diameter. Using this toner, image formation was performed in the same manner as in Example 2.
Images with good quality and density were obtained.

Ei Wataru ion exchange water 1000tJ! and Na, cos anhydrous salt8.
Pour 46g into a TK homomixer (manufactured by Tokushu Kika Kogyo).
The mixture was stirred at 10,000 rpm. ZnCj! A solution prepared by dissolving 12.3 g of ZnCO anhydride in 200*u of ion-exchanged water was gradually added to the above Nag Co3 solution while stirring with the above homomixer, and a dispersion medium containing ZnCO5 (pH-
Approximately 5.8) was obtained. When measured using a Coulter counter, the volume average diameter of ZnC01 in the dispersion medium was 2.
9 μm, and the proportion of particles with a particle size of 4.0 μm or more was 1% or less in number.

Using the ZnC0-containing dispersion medium obtained above and the monomer composition of Example 3, Example 3 was carried out at 50° C. under N atmosphere.
It was granulated in the same manner. Then, while stirring with a paddle stirring blade,
1.69 g of anhydrous sodium carbonate and anhydrous zinc chloride 2.
46g of the above dispersion medium and stirred at 50℃
Polymerization was carried out at 70° C. for 4 hours.

Thereafter, a toner was obtained in the same manner as in Example 3.

The particle size of the obtained toner was measured using a Coulter counter, and the volume average diameter was 9.5 μm. When this toner was used to produce an image in the same manner as in Example 3, an image with good image quality and density was obtained.

K1 Wataru 1 Ion exchange water 500 ■ 1 Na, Co, anhydrous salt 4.2
10. Add 3g and mix using a TK homomixer (manufactured by Tokushu Kika Kogyo). Stirred at OOO rpm. ZnCj! A solution of 6.15 g of dianhydrous salt dissolved in 200 L of ion-exchanged water was added to the above Na and Co solution.

Add ZnCO3 gradually to the solution while stirring with a homomixer.
A dispersion medium containing the following was obtained.

Meanwhile, in another container, Na, Co@
5.25 g of anhydrous salt and CaCf12 hydrate salt (CaCA*
・2H*O) 9.8g was used to obtain a dispersion medium containing CaC0.

The two dispersion media, the ZnCO5-containing dispersion medium and the CaCO5-containing dispersion medium obtained above, were mixed to obtain a dispersion medium (pH-about 5.8) used in this example.

The volume average diameter of the inorganic fine powder in this dispersion medium was 2.9 μm.

Using the dispersion medium thus obtained, granulation was carried out in the same manner as in Example 3 using the monomer composition of Example 3. after that,
While stirring with a paddle stirring blade, add 0.8 ml of sodium carbonate anhydrous salt.
46 g and 1.23 g of anhydrous zinc chloride were added to the above dispersion medium, and polymerization was carried out at 50° C. for 6 hours and at 80° C. for 4 hours while stirring.

Thereafter, a toner was obtained in the same manner as in Example 3. The volume average diameter of the obtained toner was 9.0 μm. When an image was produced using this toner in the same manner as in Example 3, an image with good image quality and density was obtained.

Medical jMU - NazCOs anhydrous salt 9 in ion exchange water 800Illfl
．． Add 98g and use TK homomixer to mix 1000g.
Stirred at 0 rpm. ZnCj! 2 Anhydrous salt 5.65g
was dissolved in 200ml of ion-exchanged water, and the above N8
Gradually add Z to the 2COs solution while stirring with a homomixer.
After obtaining a dispersion medium containing n COs, CaCfL2
9.8g of hydrated salt and 200mj of ion-exchanged water! was gradually added to the above dispersion medium while stirring with a homomixer to obtain a dispersion medium containing CaCO3 and ZnC0 (pH - about 7.5°).

The volume average diameter of the inorganic fine powder in this dispersion medium was 2.7 μm.

Granulation was carried out in the same manner as in Example 2 using the dispersion medium obtained above and the monomer composition of Example 2.

Thereafter, while stirring with a paddle stirring blade, 50 g of a dispersion medium containing zinc carbonate prepared by adding 0.946 g of sodium carbonate hydrate and 1.13 g of zinc chloride hydrate to 50 g of ion-exchanged water was added, and the above stirring was continued. Below, at 50℃ for 7 hours, 8
Polymerization was carried out at 0°C for 3 hours.

Thereafter, a toner was obtained in the same manner as in Example 2. The volume average diameter of the obtained toner was 10.5 μI. When image printing was performed using this toner in the same manner as in Example 2,
Images with good quality and density were obtained.

K1 Ko 1 ion exchange water 10100O! Na, PO4 hydrated salt 30
．． Pour 8g into TK Homo Mixer (Special Machinery Industry)
10. Stirred at OOO rpm. AJ! 2
(504) 28 g of hydrated salt and 200 g of ion-exchanged water
(2) A solution dissolved in L was gradually added to the above Na5PO4 solution while stirring with a homomixer, and a dispersion medium containing aluminum phosphate (pH-4) was added.

5) was obtained.

The particle size of aluminum phosphate in this dispersion medium is
When measured using a counter, the proportion of particles with a particle size of 4.0 μm or more was 1% in number.

Granulation was carried out in the same manner as in Example 3 using the dispersion medium obtained above and the monomer composition of Example 3.

Then, while stirring with a paddle stirring blade, 50 g of a dispersion medium containing aluminum phosphate prepared by adding 3.08 g of sodium phosphate hydrate and 2.8 g of aluminum sulfate hydrate to 50 g of ion-exchanged water was added. Under the above stirring, 5
Polymerization was carried out at 0°C for 7 hours and at 70°C for 3 hours.

Thereafter, a polymerized toner was obtained in the same manner as in Example 3.

When image formation was carried out in the same manner as in Example 3 using this polymerized toner, a good image was obtained as in Example 3.

E1 Sato Kami Ion Exchange Water 10001JZ Nas PO4/12H
2,024.5 g was added and stirred at 10,000 rpm using a TK homomixer (Tokushu Kika Kogyo). Ca
CJ2* ・2H2014゜2g ion-exchanged water 20
A solution dissolved at 0 mA was gradually added to the above Na3PO4 solution while stirring with a homomixer to obtain a dispersion medium (pH-10.5) containing calcium phosphate. When the particle size of the above calcium phosphate was measured using a Coulter counter, the proportion of particles with a particle size of 4.0 g or more was 1% in number.
It was below.

In place of 10 g of cyclized rubber in Example 1, a polyester (acid value 10, hydroxyl value 15) which is a condensation product of etherified diphenol, terephthalic acid, and trimellitic anhydride was used.
The same composition as in Example 1 was used except that 10 g was used,
In addition, granulation was performed in the same manner as in Example 1 using the calcium phosphate-containing dispersion medium obtained above.

Thereafter, 2.45 g of sodium phosphate hydrate and 1.42 g of calcium chloride hydrate were added to the above dispersion medium while stirring with a paddle stirring blade, and the mixture was heated at 50°C for 7 hours and at 70°C for 3 hours while stirring. Time polymerization was performed. Thereafter, the same treatment as in Example 1 was carried out to obtain a toner.

When this toner was used to produce an image in the same manner as in Example 1, a good image was obtained as in Example 1.

Na3PO, hydrated salt,
10. Add 30.8g and use a TK homomixer (Tokushu Kika Kogyo). Stirred at OOO rpm. AlI
3'(304)s 28g of hydrated salt and 200g of ion-exchanged water
Add the solution dissolved in A to the above Na5PO4 solution,
It was gradually added to a homomixer while stirring to obtain a dispersion medium (pH-4, 5) containing aluminum phosphate.

The particle size of aluminum phosphate in this dispersion medium is
When measured using a counter, the proportion of particles with a particle size of 4.0 pra or more was 1% in number.

A monomer composition was polymerized in the same manner as in Example 1 except that the dispersion medium obtained above was used, but a stable granular polymer could not be obtained.

Na3PO4・1282 in 1000mft of Ekoyu ion exchange water
Add 24.5 g of 0 and mix to and oo using a TK homomixer (Tokushu Kika Kogyo).

Stir at rpl. CaCAz @ 2Ha O14
A solution of 2g dissolved in 200mfL of ion-exchanged water,
A dispersion medium containing calcium phosphate was obtained by gradually adding 0.15 g of a 20% aqueous solution of sodium dodecylbenzenesulfonate to the above Na5P"04 solution while stirring with a homomixer. When measured with a Coulter counter, the particle size was 4.0g1
The proportion of the above particles was 1% or less in number.

A toner was obtained in the same manner as in Example 2 except that the dispersion medium obtained above was used.

After classifying the obtained toner into a volume average diameter of 9.5 μm,
When an image was produced in the same manner as in Example 2 using this classified toner, only a rough image was obtained at 32.5° C. and 90% high temperature and high humidity.

The interfacial tension (A) between the monomer composition used in each of the Examples and Comparative Examples above (model composition) from which the colorant has been removed and the dispersion medium, and the model composition and ion-exchanged water. The interfacial tension (B) was measured in the same manner as in Example 1.

Determined from the values of these interfacial tensions (A) and (B) -A The values of (-X 100) are shown in the table below.

The following results were obtained at the interfacial tension measurement temperature (room temperature) using a model composition that did not contain a polymerization initiator and paraffin wax 1550F, which may have an adverse effect on the measurement results.

[Brief explanation of the drawing]

The drawing is a schematic cross-sectional view showing a developing device used in Examples. 1... Image carrier 2... Sleeve 3... Magnet roller 4... Supply roller 5... Elastic member 6... Developer 7... Doctor blade 8.9... Bias power supply 10-・Developer layer regulation member

Claims (1)

[Claims] 1. Contains a poorly water-soluble inorganic dispersant powder soluble in Brønsted acid, and has a pH of 2.5 to 6.0 or 7.1 to 11.
．． A method of polymerizing a monomer composition containing at least a polymerizable monomer, a polar substance, and a colorant in a dispersion medium that is within the range of 0 and does not substantially contain a water-soluble surfactant. The interfacial tension (A) between the monomer composition excluding the colorant and the dispersion medium is 95≧(B−A)/B×100≧5 (in the above formula , B represents the interfacial tension between the monomer composition excluding the colorant and ion-exchanged water.)
A method for producing a polymerized toner that satisfies the following relationship and further comprises adding a poorly water-soluble inorganic dispersant to a polymerization system containing monomer composition particles during the polymerization of the monomer composition. .