JP2000010341A - Production of polymerized toner grain - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a polymerized toner grain supplied to a toner capable of providing a more stable image even in endurance without being accompanied by a remarkable reduction in chargeability even under high temperature/high humidity by performing the filtration of a colored resin particle from a liquid medium by filter press. SOLUTION: A polymeric monomer composition containing a polymeric monomer and a coloring agent is polymerized in a liquid medium to generate a colored resin particle, and filtration of the colored resin particle from the liquid medium is performed by filter press. In this case, slurry to which a dispersion stabilizer is dissolved is supplied to a filtering chamber through a liquid feed port 3. The filtrate passed through a filter 2 is discharged through a filtrate port/wash water port 4. After compression, the wash water is supplied from the filtrate port/wash water port 4 through the filter 2 to wash the cake, and discharged through a wash water port 5. After the washing ended, ventilation is performed to set the moisture content of the cake to 40% or less. Thereafter, each filter plate 1 is separated to discharge the cake. The cake is dried by a drier.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a toner for developing a latent electrostatic image or a polymerized toner particle used for forming a toner image in a toner jet recording method.

[0002]

2. Description of the Related Art Conventionally, many methods have been known as electrophotography. In general, a photoconductive substance is used to form an electric latent image on a photoreceptor by various means. The latent image is developed with toner to form a visible image, the toner image is transferred to a transfer material such as paper if necessary, and then the toner image is fixed on the transfer material by heat, pressure, etc. Is what you get.

Various methods have been conventionally proposed as a method of developing with toner or a method of fixing a toner image.

Conventionally, toners used for these purposes are:
Generally, a colorant comprising a dye or a pigment is melt-kneaded in a thermoplastic resin, uniformly dispersed, then finely pulverized by a fine pulverizer, and the finely pulverized material is classified by a classifier to obtain a desired particle size. Has been manufactured.

[0005] Although this method can produce fairly good toners, it does have certain limitations, namely the choice of toner materials. For example, the resin colorant dispersion must be sufficiently brittle and capable of being pulverized in an economically feasible manufacturing apparatus. However, when the resin colorant dispersion is fragile to satisfy these requirements, when the dispersion is actually pulverized at a high speed, the particle size range of the formed particles tends to be widened, particularly at a relatively large ratio. There is a problem that fine particles are contained therein. Further, the toner obtained from such a highly brittle material is liable to be further powdered in a developing device such as a copying machine. Further, in this production method, it is difficult to completely and uniformly disperse solid fine particles such as a colorant in a resin, and depending on the degree of the dispersion,
Careful attention must be paid to the dispersing of the colorant because it causes fog increase during image formation, lower image density, and poor color mixing or transparency. Further, exposure of the coloring agent to the fracture surface of the pulverized particles may cause a change in development characteristics.

On the other hand, in order to overcome the problems of the toner caused by these pulverization methods, Japanese Patent Publication Nos.
Various polymerization toners and production methods thereof have been proposed, including the suspension polymerization toners disclosed in Japanese Patent Nos. 10799 and 51-14895 and the like. For example, in a suspension polymerization toner, a polymerizable monomer, a colorant and a polymerization initiator, and further, if necessary, a crosslinking agent, a charge control agent, and other additives are uniformly dissolved or dispersed to prepare a monomer composition. After that, the monomer composition is dispersed in a medium containing a dispersion stabilizer, for example, an aqueous phase using a suitable stirrer, and simultaneously subjected to a polymerization reaction to form toner particles having a desired particle size. obtain. In this method, since the pulverizing step is not included at all, the toner does not need to be brittle, a soft material can be used as the resin, and the colorant is not exposed on the particle surface, and the uniformity can be obtained. There is an advantage that a toner having triboelectricity can be obtained. Also, even if the classification step is omitted or classified because the particle size distribution of the obtained toner is relatively sharp,
A toner can be obtained with a high yield.

However, since the polymerized toner directly generates toner particles in the medium, the toner surface is easily affected by the medium.

For example, when the medium is an aqueous medium, generally a polar resin having a high polarity or a charge control agent tends to be localized near the toner surface. As a result, compared with the pulverized toner, a very small amount of the charge control agent can uniformly impart high chargeability to the toner, but a highly polar material such as the charge control agent is a very small part, Some are dissolved in an aqueous medium. Therefore, great care must be taken in the step of filtering the toner particles from the medium after the completion of the polymerization reaction.

That is, it is important how to efficiently and uniformly clean the surface of each toner particle. If the surface of each toner particle is not washed uniformly, the charge amount distribution of the toner becomes broad, and fog, toner scattering,
Image density reduction and the like are likely to occur.

[0010] In the polymerization toner disclosed in JP-A-8-160661 and its production method, the dispersion stabilizer is efficiently removed by performing dehydration and washing with a continuous belt filter and a siphon pillar type centrifuge, It is proposed that the above problems can be solved. If polymerized toner is manufactured using these proposed devices, a toner having excellent chargeability can be obtained as compared with the conventional one, but in terms of filtration efficiency and more uniform cleaning of the toner surface. Not satisfactory.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to produce polymerized toner particles which can be used in a toner capable of obtaining a more stable image even at the time of durability without a significant decrease in chargeability even at high temperature / high humidity. It is to provide a method.

Another object of the present invention is to provide a method for producing polymerized toner particles having excellent productivity.

[0013]

According to the present invention, a polymerizable monomer composition containing at least a polymerizable monomer and a colorant is polymerized in a liquid medium to produce colored resin particles. A method for producing polymerized toner particles by filtering the colored resin particles from a liquid medium and drying the polymerized toner particles, wherein the filtration of the colored resin particles from the liquid medium is performed by a filter press method. And a method for producing the same.

As a result of extensive studies, the present inventors have found that the method of filtering the colored resin particles from the medium has a great effect on further improving the chargeability of the polymerized toner particles under high temperature / high humidity. I found that.

In general, methods of separating solid particles from a slurry are mainly classified into reduced pressure filtration, centrifugal filtration, and pressure filtration. Among them, the filter press method, which is pressure filtration, is used for polymerized toner particles. Found to be most suitable for the manufacture of

In the vacuum filtration and the centrifugal filtration, since a part of the cake is cracked and the filter is easily clogged during the filtration, it is difficult for the washing water to uniformly wash the cake.

On the other hand, in the filter press, filtration under reduced pressure and dehydration by pressing can be continuously performed, and cracking of the cake is unlikely to occur. By flowing washing water through the cake, the filtration and washing steps are continuously performed. It is very efficient because it can be done. Further, it is easy to control the amount of the washing water, the flow rate of the washing water, the pressing pressure and the like, and the filtration can be performed without impairing the chargeability of the toner.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, it is preferable that the colored resin particles are separated by filtration and then washed with water. Further, the washing is carried out using 200 to 1000 parts by weight of water per 100 parts by weight of the colored resin particles. Is preferred. 20 washing water
If the amount is less than 0 parts by weight, the dispersant is insufficiently removed, and the obtained toner has high hygroscopicity and deteriorates the chargeability. Conversely, if it exceeds 1000 parts by weight, a part of the polar components on the toner surface is eluted, and the chargeability is reduced.

Further, per 100 parts by weight of the colored resin particles,
It is preferable to wash with water at a flow rate of 10 to 50 parts by weight / min. If the flow rate is less than 10 parts by weight / min, the tact of filtration and washing with water will be long, and a part of the polar components on the toner surface will be easily eluted, and the chargeability will be reduced. Conversely, if it exceeds 50 parts by weight / min, the surface of the toner particles cannot be uniformly washed, and the charge amount distribution becomes broad.

Further, it is preferable that the filter used in the filter press method has a ventilation volume of ² to 40 cc / cm ² · min. If the ventilation amount is less than ² cc / cm ² · min, clogging of the filter is likely to occur, and not only efficiency of filtration is lowered, but also uniform washing becomes difficult. Conversely, if the air flow exceeds 40 cc / cm ² · min, some of the toner particles pass through the filter, which is not preferable.

The pressing pressure of the filter press method is as follows:
It is preferably ¹ to 10 kg / cm ² . When the pressing pressure is less than 1 kg / cm ² , not only does the efficiency of filtration drop, but also the uniform pressure is not applied to the cake in the filtration chamber, and uniform washing becomes difficult. Conversely, 10k
If it exceeds g / cm ² , the toner particles are undesirably deformed and the high transferability due to the spherical shape of the polymerized toner is impaired.

It is preferable that the toner particles are washed with water and then ventilated to reduce the water content to 40% or less. Water content is 40
%, If the drying is performed in the next step, the drying efficiency will be poor, and the obtained toner will often be in an aggregated state, which is not preferable.

The water washing by the filter press method is as follows.
It is preferable to supply water at least from the filter side. Thereby, not only can clogging of the filter be reduced, but also washing water is uniformly distributed in the cake, and unevenness of washing is less likely to occur.

In the present invention, a toner particle having a shape factor SF-1 of 100 to 160 and a toner particle having a shape factor SF-2 of 100 to 140 is suitably used. More preferably, SF-1 is 100-1.
50 and SF-2 are 100 to 130.

SF- indicating the shape factor used in the present invention
1, SF-2 is FE-SEM (S-8 manufactured by Hitachi, Ltd.)
00), 100 toner images were randomly sampled, and the image information was introduced into an image analysis device (Luzex3) manufactured by Nicole via an interface and analyzed.
In the present invention, the values calculated from the following equations are defined as shape factors SF-1 and SF-2.

[0026]

(Equation 1) [AREA: Projected area of toner particles, MXLNG: Absolute maximum length of projected toner particles, PERI: Perimeter]

The shape factor SF-1 of the toner particles indicates a degree of sphere, and if it is larger than 160, the shape gradually becomes irregular from a sphere. SF-2 indicates the degree of unevenness, and if it is larger than 140, the unevenness of the toner particle surface becomes remarkable.

The effect of the shape of the toner particles is that the external additives on the surface of the toner particles are effectively acted on as much as possible. That is, it is preferable that the toner particles have a small spherical surface area.

If SF-1 exceeds 160 or SF-2 exceeds 140, transferability and durability may be poor.

The toner of the present invention preferably contains a substance having a low softening point in order to improve fixability.
Compounds having a main maximum peak value measured according to ASTM D3418-8 of from 40 to 90 ° C are preferred. When the maximum peak is less than 40 ° C., the self-cohesive force of the low softening point substance becomes weak, and as a result, the hot offset resistance becomes weak, which is not preferable. On the other hand, if the maximum peak exceeds 90 ° C., the fixing temperature becomes high, which is not preferable. Further, in the case of obtaining a toner by a direct polymerization method, since the temperature of the maximum peak value is high because the granulation and polymerization are performed in an aqueous system, a substance having a low softening point mainly precipitates during the granulation and hinders the suspension system. Not preferred.

In the measurement of the temperature of the maximum peak value of the present invention,
For example, DSC-7 manufactured by Perkin Elemer Inc. is used. The temperature correction of the device detection unit uses the melting points of indium and zinc, and the heat quantity correction uses the heat of fusion of indium. An aluminum pan was used as a sample, an empty pan was set as a control, and the temperature was raised at a rate of 10 ° C./min.

Specifically, paraffin wax, polyolefin wax, Fischer-Tropsch wax, amide wax, higher fatty acid, ester wax, derivatives thereof, and graft / block compounds thereof can be used.

The low softening point substance is preferably added to the toner in an amount of 3 to 30% by weight. If the addition is less than 3% by weight, the fixability is lowered. If the addition is more than 30% by weight, toner particles are apt to coalesce during granulation even in production by a polymerization method, and a particle having a wide particle size distribution is formed. Easy,
It was unsuitable for the present invention. As a specific method for encapsulating the low softening point substance, the polarity of the material in the aqueous medium is set to be smaller for the low softening point substance than for the main monomer, and a small amount of a large polar resin or monomer is used. Is added, a toner having a so-called core / shell structure in which a substance having a low softening point is coated with an externally added resin can be obtained.

The particle size distribution and the particle size of the toner can be controlled by changing the type and amount of a poorly water-soluble inorganic salt or a dispersing agent acting as a protective colloid, or by mechanical device conditions such as the peripheral speed of the rotor and the number of passes. The predetermined toner of the present invention can be obtained by controlling the stirring conditions such as the shape of the stirring blade, the shape of the container, and the solid content concentration in the aqueous solution.

The polymerizable monomer used in the present invention includes styrene, o (m-, p-)-methylstyrene, m
Styrene monomers such as (p-)-ethylstyrene; methyl (meth) acrylate, ethyl (meth) acrylate,
Propyl (meth) acrylate, butyl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, behenyl (meth) acrylate, 2-ethylhexyl (meth) acrylate (Meth) acrylate monomers such as dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate; ene monomers such as butadiene, isoprene, cyclohexene, (meth) acrylonitrile, and acrylamide The body is preferably used. These can be used alone or in general in the published Polymer Handbook, 2nd edition III-pl39-192 (John Wire
y & Sons), the theoretical glass transition temperature (T
The monomer is appropriately mixed and used so that g) indicates 40 to 75 ° C. If the theoretical glass transition temperature is lower than 40 ° C., problems arise in terms of the storage stability of the toner and the durability stability of the developer. In some cases, the color mixture of each color toner is insufficient, resulting in poor color reproducibility.
The transparency of the HP image is significantly reduced, which is not preferable from the viewpoint of high image quality.

The molecular weight of the binder resin is measured by GPC (gel permeation chromatography). As a specific GPC measurement method, a toner is extracted in advance with a toluene solvent using a Soxhlet extractor for 20 hours, and then toluene is distilled off with a rotary evaporator. After adding an organic solvent that cannot be dissolved, for example, chloroform, and washing well, the solution dissolved in THF (tetrahydrofuran) was filtered through a solvent-resistant membrane filter having a pore diameter of 0.3 μm. 150C, column composition was A-801, 802, 80 manufactured by Showa Denko
3, 804, 805, 806, 807 can be linked and the molecular weight distribution can be measured using a standard polystyrene resin calibration curve. The number average molecular weight (Mn) of the obtained resin component is 500.
Binder resins having a weight average molecular weight (Mw) and a number average molecular weight (Mn) of 2 to 100 (Mw / Mn) are preferred in the present invention.

In the present invention, when a toner having a core / shell structure is produced, it is particularly preferable to add a polar resin. The polar resin used in the present invention includes a copolymer of styrene and (meth) acrylic acid,
Maleic acid copolymers, polyester resins and epoxy resins are preferably used. It is particularly preferable that the polar resin does not contain an unsaturated group capable of reacting with a monomer in the molecule.
If a polar resin having many unsaturated groups is included, a cross-linking reaction occurs with the monomer forming the outer shell resin layer,
In particular, a full-color toner has an extremely high molecular weight and is disadvantageous for color mixing of four-color toner, which is not preferable.

In the present invention, an outermost resin layer may be further provided on the surface of the toner. The glass transition temperature of the outermost shell resin layer is preferably designed to be equal to or higher than the glass transition temperature of the outer shell resin layer in order to further improve blocking resistance, and it is preferable that the outermost shell resin layer is crosslinked so as not to impair fixability. . The outermost resin layer preferably contains a polar resin and a charge control agent for improving the chargeability.

The method for providing the outermost shell layer is not particularly limited, but examples thereof include the following method.

1. In the second half or after the end of the polymerization reaction, if necessary, a monomer in which a polar resin, a charge control agent, a cross-linking agent, etc. are dissolved and dispersed is added to the reaction system, the monomer is adsorbed, polymerized particles are added, and a polymerization initiator is added to perform polymerization. Method.

2. If necessary, an emulsion polymerization particle or a soap-free polymerization particle composed of a monomer containing a polar resin, a charge control agent, a cross-linking agent, etc. is added to the reaction system, and aggregated on the surface of the polymerization particle.If necessary, heat or the like is used. How to stick.

3. A method in which emulsion polymerized particles or soap-free polymerized particles comprising a monomer containing a polar resin, a charge control agent, a cross-linking agent, and the like, if necessary, are dry-mechanically fixed to the toner particle surfaces.

As the colorant used in the present invention, a black colorant prepared by using carbon black, a magnetic substance, and a yellow / magenta / cyan colorant shown below as a black colorant is used.

Examples of the yellow colorant include condensed azo compounds, isoindolinone compounds, anthraquinone compounds,
Compounds represented by azo metal complexes, methine compounds and allylamide compounds are used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 6
2, 74, 83, 93, 94, 95, 109, 110,
111, 128, 129, 147, 168, 180 and the like are preferably used.

Examples of the magenta colorant include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds and perylene compounds. Specifically, C.I.
I. Pigment Red 2, 3, 5, 6, 7, 23, 4
8: 2, 48: 3, 48: 4, 57: 1, 81: 1, 1
22, 144, 146, 166, 169, 177, 18
4, 185, 202, 206, 220, 221, 254
Is particularly preferred.

As the cyan coloring agent, copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds and the like can be used. Specifically, C.I. I.
Pigment Blue 1, 7, 15, 15: 1, 15: 2,
15: 3, 15: 4, 60, 62, 66, etc. can be particularly preferably used.

These colorants can be used alone or as a mixture or in the form of a solid solution. In the case of a color toner, the colorant of the present invention is selected from the viewpoints of hue angle, saturation, lightness, weather resistance, OHP transparency, and dispersibility in the toner. The amount of the coloring agent is 1 to 100 parts by weight of the resin.
Used in an amount of up to 20 parts by weight.

When a magnetic material is used as a black colorant, unlike other colorants, 40 to 100 parts by weight of resin is used.
Used by adding 150 parts by weight.

The charge control agents used in the present invention include:
Although a known toner can be used, in the case of a color toner, a charge control agent which is colorless, has a high toner charging speed, and can stably maintain a constant charge amount is particularly preferable.

Specific examples of the compound include negative compounds such as metal compounds of salicylic acid, naphthoic acid, dicarboxylic acid, and derivatives thereof, sulfonic acids, high molecular compounds having carboxylic acids in their side chains, boron compounds, urea compounds, and silicon compounds. A compound, calixarene and the like can be used, and a quaternary ammonium salt, a high molecular compound having the quaternary ammonium salt in a side chain, a guanidine compound, an imidazole compound and the like are preferably used as the positive system.

The charge control agent is preferably added in an amount of 0.5 to 10 parts by weight based on 100 parts by weight of the resin.

Examples of the polymerization initiator used in the present invention include 2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile,
1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis-4-methoxy-2,4-
Azo-based polymerization initiators such as dimethylvaleronitrile and azobisisobutyronitrile; benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-
A peroxide-based polymerization initiator such as dichlorobenzoyl peroxide and lauroyl peroxide is used.

The amount of the polymerization initiator to be added varies depending on the target component ratio of the present invention, but is generally 0.5 to 20% by weight, more preferably 0.5 to 10% by weight, based on the monomer. % Used. Although the type of the initiator slightly varies depending on the polymerization method, it is used alone or in combination with reference to the 10-hour half-life temperature.

In order to control the molecular weight distribution of the binder resin for toner of the present invention, it is preferable to further use a known crosslinking agent, chain transfer agent, polymerization inhibitor and the like.

When the suspension polymerization is used as the toner production method of the present invention, for example, tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate may be used as a dispersant such as an inorganic oxide. , Magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, alumina, magnetic material, ferrite and the like.
Examples of the organic compound include polyvinyl alcohol,
Gelatin, methylcellulose, methylhydroxypropylcellulose, ethylcellulose, sodium salts of carboxymethylcellulose, starch and the like are used by being dispersed in an aqueous phase.

These dispersants are used in the polymerizable monomer composition 10
It is preferable to use 0.2 to 10.0 parts by weight with respect to 0 parts by weight.

As these dispersants, commercially available ones may be used as they are, but in order to obtain finely dispersed particles having a uniform particle size, the inorganic compound is formed under high-speed stirring in a dispersion medium. You can also get.

For example, in the case of tricalcium phosphate, a dispersant suitable for a suspension polymerization method can be obtained by mixing an aqueous solution of sodium phosphate and an aqueous solution of calcium chloride under high-speed stirring.

In addition, these dispersants may be used in an amount of 0.001 to 0.
One part by weight of a surfactant may be used in combination. Specifically, commercially available nonionic, anionic, and cationic surfactants can be used, and examples thereof include sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate, and olein. Calcium acid and the like are preferably used.

The method for producing the toner of the present invention is specifically performed as follows.

A release agent comprising a low softening point substance in a monomer,
A colorant, a charge control agent, a polymerization initiator and other additives are added, and the monomer composition uniformly dissolved or dispersed by a homogenizer, an ultrasonic disperser or the like is usually added to an aqueous phase containing a dispersion stabilizer. With a stirrer, homomixer, homogenizer or the like. In the suspension polymerization method, usually, 300 to 30 parts of water is added to 100 parts by weight of the monomer system.
It is preferable to use 00 parts by weight as a dispersion medium.

The granulation is preferably performed by adjusting the stirring speed and time so that the droplets of the monomer composition have the desired size of the toner particles. Thereafter, by the action of the dispersion stabilizer, the particles may be stirred to such an extent that the particle state is maintained and the particles are prevented from settling. The polymerization is performed at a polymerization temperature of 40 ° C. or higher, generally 50 to 90 ° C. Further, the temperature may be raised in the latter half of the polymerization reaction, and furthermore, in the latter half of the reaction to remove unreacted polymerizable monomers, by-products, and the like, or by partially distilling the aqueous medium after completion of the reaction. Is also good.

After the completion of the reaction, the pH is adjusted, the dispersion stabilizer is dissolved, and the resulting toner particles are collected by washing, filtration, and dried.

The filtering and washing of the toner particles, which is a feature of the present invention, will be described with reference to FIG.

The slurry in which the dispersion stabilizer is dissolved is supplied from the liquid feed port 3 into the filtration chamber. The filtrate that has passed through the filter cloth 2 is discharged from a filtrate port / wash water port 4. After the squeezing, the washing water is supplied from the filtrate port / washing water port 4 through the filter cloth 2 to wash the cake, and the washing water port 5 is further discharged.
After the washing is completed, aeration is performed using 4 or 5 to reduce the water content of the cake to 40% or less. Thereafter, the filter plates 1 are separated from each other, and the cake is discharged.

The discharged cake is dried by a dryer such as a fluidized bed dryer, a flash dryer and a vacuum dryer. An external additive may be added to the toner of the present invention to impart various toner properties. As the external additive used, for example,
The following are used: metal oxides (aluminum oxide, titanium oxide, strontium titanate, cerium oxide, magnesium oxide, chromium oxide, tin oxide, zinc oxide, etc.), nitrides (silicon nitride, etc.), carbides (carbonized) Metal salts (calcium sulfate, barium sulfate, calcium carbonate, etc.), fatty acid metal salts (zinc stearate, calcium stearate, etc.), carbon black, silica, etc.

These external additives are used in an amount of 0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight, based on 100 parts by weight of the toner particles. These external additives may be used alone or in combination. Respectively,
Those subjected to a hydrophobic treatment are more preferable.

As a device for measuring the average particle size and the particle size distribution of the toner, Coulter Counter TA-II or Coulter Multisizer II (manufactured by Coulter Inc.) is used. The electrolyte is about 1% Na using primary sodium chloride.
Prepare a Cl aqueous solution. As a measurement method, a surfactant as a dispersant in 100 to 150 ml of the electrolytic aqueous solution,
Preferably, the alkyl benzene sulfonate is 0.1 to 5
ml, and 2 to 20 mg of the measurement sample. The electrolytic solution in which the sample was suspended was subjected to dispersion treatment for about 1 to 3 minutes using an ultrasonic disperser, and the volume and number of the toner were measured by using the measuring device with a 100 μm aperture as the aperture. Distribution was calculated. Then, the volume-based weight average particle diameter (D4) (the representative value of each channel is set as the representative value of each channel) determined from the volume distribution according to the present invention was determined.

The details of the toner evaluation items in the examples described below are as follows.

The degree of agglomeration was measured using a powder tester PT-N type (manufactured by Hosokawa Micron) as # 100, # 200, #
Using 400 mesh and 5 g of toner, an amplitude of 1.5 mm /
It was calculated by the following general formula under the condition of 15 seconds.

[0071]

(Equation 2)

The image evaluation was carried out using LBP-20 manufactured by Canon Inc.
30 modified machine, temperature 30 ℃, humidity 80% high temperature /
A durability test was continuously performed on 3000 sheets in a high humidity environment.

The image density is (5 mm square, 5 mm round, solid)
Is a numerical value measured by a Macbeth densitometer (manufactured by Macbeth).

The fog density was measured using a reflection densitometer (TOKYO).
DENSHOKU CO. LTD REFLECT
OMETER MODEL TC-6DS) (Ds is the worst value of the reflection density of the white background after printing is Ds, and Ds is the average reflection density of the paper before printing is Dr).
Dr was defined as the fog density. )did. When the fog density exceeds 2%, an image in which fog is conspicuous is formed.

[0075]

Hereinafter, the present invention will be described in detail with reference to specific toner production methods, examples and comparative examples.

<Example 1> To 700 parts by weight of ion-exchanged water, 450 parts by weight of an aqueous 0.1 M Na ₃ PO ₄ solution were added, and the mixture was heated to 60 ° C and then CLEARMIX CLS-3.
4500 rpm using OSS (manufactured by M Technique Co., Ltd.)
m. A 1.0 M CaCl ₂ aqueous solution 6
Eight parts by weight were gradually added to obtain an aqueous medium containing a calcium phosphate salt.

On the other hand, (monomer) 170 parts by weight of styrene 30 parts by weight of n-butyl acrylate (colorant) I. Pigment Blue 15: 3 10 parts by weight (Charge control agent) Di-t-butylsalicylic acid metal compound 2 parts by weight (Polar resin) Saturated polyester 15 parts by weight (Acid value 10, Peak molecular weight 8500) (Release agent) Ester wax (Melting point 65 ° C) 40 parts by weight Divinylbenzene 0.2 parts by weight The above formulation was heated to 60 ° C, and was uniformly dissolved and dispersed. Into this, 8 parts by weight of a polymerization initiator 2,2′-azobis (2,4-dimethylvaleronitrile) was dissolved to prepare a polymerizable monomer composition.

The polymerizable monomer composition was charged into the aqueous medium, and the mixture was stirred at 4500 rpm for 15 minutes in a clear mix at 60 ° C. in an N ₂ atmosphere to granulate the polymerizable monomer composition. did.

Thereafter, while stirring with a paddle stirring blade, 70
C., and reacted for 10 hours. After the completion of the polymerization reaction, 8
The remaining monomer was distilled off at 0 ° C./reduced pressure, and after cooling, hydrochloric acid was added to dissolve the calcium phosphate salt. Then, a filter press (NR-PF-BL type: manufactured by Noritake Ironworks Co., Ltd., filter flow rate 20 cc / cm ^2. min, pressing pressure 5 kg / c
Using m ² ), filtration and washing were performed under the conditions shown in Table 1. Thereafter, drying was performed to obtain colored resin particles (toner particles).

To 100 parts by weight of the obtained toner particles, 1.0 part by weight of hydrophobic silica having a specific surface area of 200 m ² / g by a BET method was externally added to obtain a toner. The obtained toner had a weight average particle size of 6.8 μm and a sharp particle size distribution. The molecular weight distribution of the resin component of the toner is M
w: 200,000, Mn: 25,000, Mw / Mn: 8,
The shape factors of the toner particles are SF-1: 108, SF-
2: 110. Other physical properties and evaluation results are shown in Table 1.

<Example 2> The coloring agent of Example 1 was replaced with C.I.
I. Pigment Yellow 17 and ventilation time 60
A toner was obtained by performing the same operation as in Example 1 except that the amount was changed to minutes. The obtained toner had a weight average particle size of 6.2 μm and a sharp particle size distribution. Other physical properties and evaluation results are shown in Table 1. The molecular weight distribution of the resin component of the toner is M
w: 220,000, Mn: 288,000, Mw / Mn: 7.86, and the shape factor of the toner particles is SF-1: 110;
F-2: 112.

<Example 3> A toner was obtained in the same manner as in Example 1 except that the filtration conditions in Example 1 were changed as shown in Table 1 (wash water amount, wash flow rate, ventilation time). The weight average particle size of the obtained toner was 6.8 μm and had a sharp particle size distribution. Other physical properties and evaluation results are shown in Table 1.

Example 4 A toner was obtained in the same manner as in Example 1 except that the filtration conditions in Example 1 were changed as shown in Table 1 (wash water amount and wash flow rate). The obtained toner had a weight average particle size of 6.2 μm and a sharp particle size distribution. Other physical properties and evaluation results are shown in Table 1.

Example 5 A toner was obtained in the same manner as in Example 1 except that the filtration conditions in Example 1 were changed as shown in Table 1 (washing method, ventilation time). The weight average particle size of the obtained toner was 6.8 μm and had a sharp particle size distribution. Other physical properties and evaluation results are shown in Table 1.

<Example 6> A toner was obtained in the same manner as in Example 1 except that the filtration conditions in Example 1 were changed as shown in Table 1 (washing flow rate, ventilation time). The weight average particle size of the obtained toner was 7.2 μm, and the particle size distribution was slightly coarse. Other physical properties and evaluation results are shown in Table 1.

Comparative Example 1 A toner was obtained by performing the same operation as in Example 1 except that the filtration device of Example 1 was changed to an Eagle filter (manufactured by Sumitomo Heavy Industries, Ltd.) which is a continuous belt filter. . The obtained toner had a weight average particle size of 8.0 μm and a particle size distribution including some coarse particles. Other physical properties and evaluation results are shown in Table 1.

Comparative Example 2 A toner was obtained by performing the same operation as in Example 1 except that the filtration device of Example 1 was changed to a basket type centrifugal separator. The weight average particle size of the obtained toner was 6.8 μm and had a sharp particle size distribution. Other physical properties and evaluation results are shown in Table 1.

[0088]

[Table 1]

[0089]

As described above, according to the present invention,
A toner having a sharp particle size distribution and excellent fluidity can be obtained.

Further, a polymerized toner which does not cause a remarkable reduction in charge even under high temperature / high humidity and can obtain a stable image even during the durability can be obtained.

[Brief description of the drawings]

FIG. 1 schematically shows a filter press apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Filter plate 2 Filter cloth 3 Liquid supply port 4 Filtrate port / wash water port 5 Wash water port

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Koji Inaba, Inventor F30 terms, 3-30-2 Shimomaruko, Ota-ku, Tokyo 2F005 AA01 AA06 AA15 AB06 CA04 CA08 CA14 DA01 EA05 4D018 AA06 BB02 BB13 BB17 BB18 BB19 BB40 CC03 CC06 DD01 DD07

Claims (12)

[Claims] 1. A polymerizable monomer composition containing at least a polymerizable monomer and a colorant is polymerized in a liquid medium to produce colored resin particles, and the colored resin particles are separated from the liquid medium by filtration. And drying the colored resin particles from a liquid medium by a filter press method. 2. The method for producing polymerized toner particles according to claim 1, wherein the colored resin particles are separated by filtration and then washed with water. 3. Water 2 per 100 parts by weight of the colored resin particles
The method for producing polymerized toner particles according to claim 2, wherein the washing is performed by using 100 to 1000 parts by weight. 4. 10 parts by weight of the colored resin particles
4. The method for producing polymerized toner particles according to claim 2, wherein water washing is performed at a flow rate of 50 to 50 parts by weight / min. 5. The method for producing polymerized toner particles according to claim 2, wherein the colored resin particles are washed with water and then ventilated to reduce the water content to 40% or less. 6. The weight average particle diameter of the colored resin particles is 3 to 10.
The method for producing polymerized toner particles according to any one of claims 1 to 5, wherein the filter used in the filter press method has an air permeability of ² to 40 cc / cm ² · min. 7. The press pressure of the filter press method is 1 to 7.
The method for producing polymerized toner particles according to any one of claims 1 to 6, wherein the pressure is 10 kg / cm ² . 8. The method for producing polymerized toner particles according to claim 2, wherein the washing with water by a filter press method is a method of supplying water from at least a filter side. 9. The method according to claim 1, wherein the polymerizable monomer further contains a charge control agent. 10. The method for producing polymerized toner particles according to claim 1, wherein the polymerizable monomer further contains a polar resin. 11. The method for producing polymerized toner particles according to claim 1, wherein the polymerizable monomer further contains a charge control agent, a polar resin, and a substance having a low softening point. . 12. The polymerization according to claim 1, wherein the produced toner particles have a shape factor of SF-1 of 160 or less and SF-2 of 140 or less. A method for producing toner particles.