JP2003131427A - Method and apparatus for manufacturing electrostatic change image developing toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing an electrostatic charge image developing toner by which a volatile component present in toner particles synthesized in an aqueous medium is uniformly removed in a short time and to provide an apparatus for manufacturing the electrostatic charge image developing toner by the method. SOLUTION: Wet toner particles obtained by washing and dewatering polymer particles synthesized in an aqueous medium are heated under reduced pressure and under irradiatin with far IR to obtain the objective toner.

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 an electrostatic charge image developing toner used in a method for developing an electrostatic latent image and a toner jet recording method, and an apparatus for producing an electrostatic charge image developing toner. .

[0002]

BACKGROUND OF THE INVENTION Electrophotography is described in U.S. Pat. No. 2,297,6.
As described in Japanese Patent No. 91, etc., a number of methods are known, and generally, a photoconductive substance is used to form an electrostatic latent image on a photoconductor by various means, and then the electrostatic latent image is formed. The latent image is developed with toner, and the toner image is transferred to a transfer material such as paper, if necessary, and then fixed by heating, pressure, solvent vapor or the like to obtain a copy. As a method of developing with toner or a method of fixing a toner image, various methods have been conventionally proposed, and methods suitable for respective image forming processes are adopted.

Conventionally, as a toner used for these purposes, a coloring agent such as a dye and a pigment is generally melt-mixed in a thermoplastic resin and uniformly dispersed, and then a desired particle diameter is obtained by a fine pulverizer and a classifier. Some toners are manufactured.
This manufacturing method has a certain limitation, that is, the selection range of the toner material. For example, a colorant dispersed in the thermoplastic resin, the resin colorant dispersion is sufficiently brittle,
It must be able to be milled with economically feasible manufacturing equipment. However, if the resin colorant dispersion is made brittle in order to meet these requirements, the particle size range of the particles formed when the particles are actually pulverized at a high speed tends to be wide, and in particular, a relatively large proportion of fine particles is The problem of being included in. Furthermore, such a brittle material is likely to undergo further fine pulverization or pulverization when used for developing such as a copying machine. Further, in this method, it is difficult to completely uniformly disperse solid fine particles such as a colorant in the resin,
Depending on the degree of dispersion, fog may increase, image density may decrease, and color mixture and transparency may be poor. Therefore, attention must be paid to dispersion. In addition, the exposure of the colorant on the fracture surface may cause fluctuations in the developing characteristics.

On the other hand, in order to overcome the problems of toner by the pulverization method, Japanese Patent Publications No. 36-10231 and 43-43.
Various polymerization toners and methods for producing the same have been proposed, including toners by the suspension polymerization method disclosed in Nos. 10799 and 51-14895. For example, the suspension polymerization method is a method in which a polymerizable monomer, a colorant, a polymerization initiator, and optionally a crosslinking agent, a charge control agent and other additives are uniformly dissolved or dispersed to form a monomer composition. After that, this monomer composition is dispersed in a continuous phase containing a dispersion stabilizer, for example, an aqueous phase, using a suitable stirrer, and at the same time, a polymerization reaction is carried out to obtain a toner having a desired particle size. This is a method of obtaining particles.

Since this method does not include a crushing step at all, the toner does not need to be brittle, a soft material can be used, and the classification step can be omitted, thereby saving energy. The cost reduction effect is great, such as reduction of time and improvement of process yield.

Further, in recent years, there has been a demand for multifunctionalization of the toner itself such as high image quality, full color and energy saving of copying machines and printers. For example, in order to support high resolution and digital methods, finer toner particles with higher image quality, transparency of OHP images with full color, and low temperature fixing with energy saving, have a low softening point. There is a demand for a toner containing a substance and having a shape that is effective for improving the transfer efficiency to a transfer material. As a means for fulfilling these demands, there is a toner by a polymerization method.

On the other hand, in the polymerization method, the reaction form including the polymerization method toner increases the viscosity of the polymerization reaction system as the polymerization progresses, and it becomes difficult for radicals and polymerizable monomers to move, so that the polymerization in the polymer occurs. A large amount of the polymerizable monomer component tends to remain. In particular, in the case of the suspension polymerization method toner, a component such as a dye, a pigment (especially carbon black), a charge control agent and a magnetic substance which may inhibit the polymerization reaction is a polymerizable monomer in the polymerizable monomer system. Since it is present in a large amount in addition to the body, the unreacted polymerizable monomer is more likely to remain.

If a large amount of a component that acts as a solvent for the binder resin is present in the toner particles, not limited to the polymerizable monomer, the fluidity of the toner is deteriorated and the image quality is deteriorated. Cause decline. In addition to the ability to be directly involved as a toner, especially when an organic semiconductor is used as a photoconductor, in addition to the phenomenon of toner fusion to the photoconductor drum, it also causes photodegradation phenomena such as memory ghosts and image blurring. It may cause problems. In addition to such matters relating to the performance of the product, there is a problem that the polymerizable monomer component volatilizes during fixing to give off a bad odor.

In order to improve the above, as disclosed in JP-A-7-92736, the residual amount of the polymerizable monomer present in the toner particles is reduced to 500 ppm or less. It has been proposed that the image quality produces a further improvement effect.

Furthermore, downsizing of copying machines, printers, etc.,
As personalization increases, the restrictions on the device increase, the load on the above-mentioned problems increases, and the interest in the environment also increases, and VOCs derived from toner particles generated during fixing and the like are increased.
(Volatile organic compounds)
Therefore, it is preferable to reduce the residual amount of the polymerizable monomer present in the toner particles to 100 ppm or less.

As a method for reducing the residual amount of the polymerizable monomer in the toner particles to a minute amount, a known means for promoting the consumption of the polymerizable monomer used in producing the binder resin by the polymerization method is known. Can be used. For example, as a method for removing the unreacted polymerizable monomer which is a means for promoting the consumption of the polymerizable monomer, the toner binder resin is not dissolved but the polymerizable monomer and / or the organic solvent component is highly dissolved. Method of washing with volatile organic solvent; Method of washing with acid or alkali; Solvent component that does not dissolve foaming agent or polymer is added to the polymer system, and the resulting toner is made porous to make polymerizable monomer inside And / or a method of increasing the volatilization area of the organic solvent component; and a method of volatilizing the main synthetic monomer and / or the organic solvent component under dry conditions. Among these, the method of evaporating the polymerizable monomer and / or the organic solvent component under the drying condition is the most preferable because it is difficult to elute the toner constituent component due to the deterioration of the toner capsule property and it is difficult to select the solvent such as the residual property of the solvent. . Conventionally, volatile components are generally removed from a toner particle after solid-liquid separation of a suspension in which a polymerization reaction is completed, using a vacuum dryer or the like.

Further, Japanese Patent Application Laid-Open No. 08-160662 proposes a method of drying toner particles under reduced pressure. Although this drying method has an advantage of being able to dry an object to be dried at a low temperature, Since it takes a lot of time to raise the product temperature to a predetermined temperature, a long drying time is required.

A toner that has undergone a long heat history has a problem that it induces many performance deteriorations such as the exudation of a low softening point substance that aggregates and encloses toner particles to the surface.

In the vacuum drying, the temperature of the material largely influences the drying rate, so the rate of rise of the product temperature is a major factor in determining the drying rate / time. Therefore,
Increasing the rate of rise of the product temperature makes it possible to remove volatile components in a short time, and further to produce a toner with less heat deterioration.

On the other hand, the depressurization type dryer is an indirect heating type having a heat transfer surface in almost all cases. In this case, when a small scale device and a large scale device are compared, they are charged in the reduced pressure dryer. Moreover, there is a demerit that the ratio of the heat transfer area to the sample to be dried becomes smaller as the scale becomes larger, and the rate of rise of the product temperature greatly changes depending on the scale. The drying time required on a small scale will take a longer time on a large scale. As a result, the above-mentioned problems caused by the long thermal history become more pronounced when attempting a scale-up.

In drying under reduced pressure, it has been a problem for many engineers to reduce the extension of the drying time caused by the difference in scale, and this is applied to the drying of toner synthesized in an aqueous medium. The same applies when used.

[0017]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for producing an electrostatic charge image developing toner and an apparatus for producing an electrostatic charge image developing which solve the above problems.

More specifically, the object of the present invention is to provide a method for producing a toner for developing an electrostatic charge image and an electrostatic charge image for uniformly removing volatile components present in polymer particles synthesized in an aqueous medium in a short time. An object of the present invention is to provide a developing toner manufacturing apparatus.

Another object of the present invention is induced by an electrostatic charge image developing toner capable of obtaining a high quality image free from image defects caused by residual volatile components, and a toner thermally deteriorated by a long thermal history. An object of the present invention is to provide a method for producing an electrostatic charge image developing toner and an apparatus for producing an electrostatic charge image developing toner for providing an electrostatic charge image developing toner capable of obtaining a high quality image without image defects.

In addition, an object of the present invention is to provide a method for producing a toner for developing an electrostatic charge image and an apparatus for producing a toner for developing an electrostatic charge image, which reduces energy and cost required for removing the volatile component. is there.

[0021]

Means for Solving the Problems The present invention is as follows. (1) For electrostatic image development having a step of obtaining wet toner particles by washing polymer particles synthesized in an aqueous medium and dehydrating them, and heating them under reduced pressure and irradiation with far infrared rays Toner manufacturing method. (2) An apparatus for producing a toner by drying wet toner particles obtained by washing and dehydrating polymer particles synthesized in an aqueous medium, the container containing the wet toner; An apparatus for producing an electrostatic charge image developing toner, comprising: a depressurizing unit for depressurizing a container, a far infrared ray irradiating unit for irradiating the wet toner particles with far infrared rays, and a heating unit for heating the wet toner particles. .

[0022]

DETAILED DESCRIPTION OF THE INVENTION As a result of earnest studies, the present inventors
The wet toner particles obtained by washing and dehydrating the polymer particles synthesized in an aqueous medium are heated under irradiation of far infrared rays under reduced pressure to efficiently remove volatile components remaining in the toner. I found that I could do it.

Far-infrared rays have a strong effect of exciting the thermal motion of a substance to raise the temperature, and by utilizing this, the product temperature of the material to be dried, which is a major factor in determining the drying speed, can be efficiently maintained up to a predetermined temperature. The volatile component is increased and the removal of volatile components is achieved faster than before.

Further, since far-infrared rays are directly heated by radiation capable of transmitting heat even in a low temperature atmosphere, they have an effect together with indirect heating which is a heating system of a conventional decompression heating device, and efficiently heat the product temperature. It is possible to rise. In the present invention, the means for raising the product temperature has both direct heating by far infrared rays and indirect heating for transmitting heat through the heat transfer surface, but the former is included in the expression "far infrared irradiation" and the latter is , Is simply distinguished by the expression "heating".

When the volatile components are removed by using the vacuum dryer as in the conventional case, there is little heat deterioration in order to cope with the recent miniaturization of copying machines, printers and the like, and the increase of restrictions on the equipment accompanying personalization. Drying time is too long to provide toner.

Further, in the decompression type dryer, the ratio of the heat transfer area to the sample to be dried charged in the dryer becomes smaller as the scale becomes larger, so that the time greatly depends on the amount of heat supplied from the transfer surface. When removing moisture and raising the temperature of the material,
In particular, there was a problem that the drying time was extended due to the difference.

Further, on a large scale, the extension of the drying time requires a long heat history, and as a result, there is a problem that the toner is damaged and the image characteristics are deteriorated.

The present invention will be described in more detail below.

The wet toner particles used in the method for producing a toner for developing an electrostatic charge image of the present invention are obtained by washing polymer particles synthesized in an aqueous medium and dehydrating them. The polymer particles will be described later.

In the method for producing a toner for developing an electrostatic image of the present invention, it is preferable that the wet toner particles obtained after washing and dehydration have a water content of 3.0%.

Next, the "water content" used in the present invention means the water content by weight, that is, the ratio of the water mass to the total mass (the sum of the dry toner mass and the water mass), and the heating loss at 105 ° C. It was obtained by law.

Further, the present invention is said to exist mainly inside the toner in order to cope with the above-mentioned restrictions on the apparatus due to miniaturization of copying machines, printers, etc., and personalization and to reduce VOC. Finally, the trace amount of the polymerizable monomer composition is also removed. However, when the wet toner particles contain a large amount of water, the water exists on the surface of the particles, and therefore the polymerizable monomer composition cannot be reduced until the water is removed. Also, when drying a material containing a large amount of water content under reduced pressure, the heat necessary for evaporation is given from the heating surface,
As well as increasing the temperature of the material to be dried, scale UP
As a result, the ratio of the amount of heat supplied to the material to be dried decreases, so that there is a difference in the time required to remove water. Therefore, in order to further improve the volatile matter removal efficiency, it is preferable to limit the water content of the wet toner particles before irradiation with far infrared rays.

The water content of the wet toner particles is, specifically,
The water content of the wet toner particles is preferably 3.0% or less,
It is more desirable that the content be 1.0% or less. As a method for adjusting the water content in advance, for example, there is a method in which the water content is dispersed in a high-speed hot air stream and at the same time, the heat treatment is preliminarily performed while being sent in parallel flow. By using a heat treatment type device capable of continuously supplying the wet toner particles into the high-speed hot air stream, the wet toner particles having the above water content can be prepared in advance.

As a means for washing and dehydrating the polymer particles synthesized in the aqueous medium, filtration can be mentioned. When filtration is used, sometimes air is sent to wash and dehydrate the material collected in the filter medium, but after being dehydrated to some extent, by further extending the time for which air is passed, the wetness with the above-mentioned water content is obtained. It is also possible to obtain toner particles.

In the present invention, the product temperature of the toner is 60 ° C.
It is preferable to irradiate far infrared rays as described below.
If the temperature of the toner exceeds 60 ° C., when the toner is used in an image forming apparatus, not only does the toner agglomerate and fuse with each other to cause a problem in the product, but also the toner is fused to the inside of the image forming apparatus. Occurs, and a large amount of labor tends to be required for cleaning and the like.

The far infrared ray used in the present invention has an emissivity of
Far-infrared radiation with a peak in the wavelength range of 4 to 20 μm
Preferably obtained from the body, preferably used
Inorganic substances are used as materials for far infrared radiators.
Made of ceramic materials, organometallic compounds, organosilicon
Examples include those that use far infrared radiation materials such as elementary compounds.
It Inorganic substances as raw materials used for ceramic materials
As Al₂O₃, SiO ₂, ZrO₂, Y₂O₃, La
₂O₃, CeO₂, Fe₂O₃, MgO, BaO, SnO₂,
Sb₂O₃, TiO₂, CuO, etc. Organic metal compound
Material or organic silicon compound, far infrared radiator material
When used as, the following compounds are specifically exemplified.
It

Alkyl metal esters, alkyl metal chelates, alkyl metal acylates, chelated metal esters, metal alkoxides, zirconium tetraacetylacetonates, and organic alkoxide silanes.

The method of irradiating far infrared rays is not particularly limited, but, for example, an agitating member may be provided at a position apart from the wet toner particles in the container containing the wet toner particles or in the container containing the wet toner particles. In some cases, a far infrared radiator can be separately provided at a position where it does not interfere. Further, the above far-infrared radiation material may be made into particles, and what is called coating or lining may be baked on the heating surface inside the container for containing the wet toner particles. Here, the weight average particle diameter of the particles made of the far infrared ray emitting material is preferably about 0.2 to 200 μm. Furthermore,
A glass layer is baked on the heating surface inside the container containing the wet toner particles, so-called glass lining is applied, and then,
It is preferable to burn the above-mentioned particulate far-infrared radiation material (far-infrared radiation material particles). Since the glass layer hardly absorbs far infrared rays, it becomes possible to irradiate far infrared rays extremely efficiently. By the methods mentioned so far,
Far infrared rays are efficiently radiated to the wet toner particles, and the temperature of the toner can be quickly raised. By the way,
The drying speed can be remarkably improved, and the extension of the drying time accompanying the scale UP can be reduced.

In addition, the far infrared ray emissivity has a peak wavelength of 4 to
It is preferable to use a far-infrared radiator having a range of 20 μm from the viewpoint of the absorption efficiency of the toner and the substances constituting the toner. Further, the peak preferably has an emissivity of at least 0.8 or more with respect to the emissivity of the black body. In the method for producing a far infrared radiator according to the present invention, a glass layer is baked on the inner surface of a container that contains wet toner particles made of metal or the like, and far infrared radiation material particles are placed thereon at a temperature of 50 to 150 higher than the baking temperature of the glass layer. Examples include a method of baking at a temperature higher by ° C to distribute the particles on the surface of the glass layer.

The glass lining method for baking the glass layer on the inner surface of the container may be a commonly employed method. If necessary, the surface of the container may be subjected to surface treatment such as sandblasting and the glass is applied to an appropriate thickness. Just bake it. As a method for applying glass, there are a dry method in which frits (glass powder) are sprinkled and a wet method in which slips (slurry glass composition) are uniformly sprayed with a spray gun, and any of these can be adopted in the present invention. The glass-coated container is dried and usually baked at a (baking) temperature of about 800 to 900 ° C. to melt and fuse the glass.

In the present invention, as the far-infrared radiator, far-infrared radiation material particles adjusted to have an appropriate particle size are dispersed in water and sprayed on the surface of the glass layer thus formed in an appropriate amount. After spraying, bake,
More preferably, the particles are distributed on the surface of the glass layer so as to be as dense as possible. At this time, it is preferable that the far-infrared emitting material particles are baked at a temperature higher by 50 to 150 ° C. than the (baking) baking temperature of the glass layer. When the baking temperature of the far-infrared emitting material particles is lower than the baking temperature of the glass layer + 50 ° C., the far-infrared emitting material particles may not be reliably baked. On the contrary, when the baking temperature of the far-infrared emitting material particles is higher than the baking temperature of the glass layer + 150 ° C., the far-infrared emitting material particles are buried inside the glass layer, and on the glass layer surface,
Alternatively, it may not be dispersed immediately below the surface. The preferable baking temperature of the far infrared ray emitting material particles is a temperature which is 60 to 120 ° C. higher than the baking temperature of the glass layer.

The far-infrared radiator thus obtained can radiate far-infrared rays in a wide range of wavelengths very efficiently.

In the present invention, when heating while irradiating with far infrared rays, as a carrier gas, in order to prevent volatile components from staying in the gas phase portion of the container and improve the drying efficiency,
It is preferable to add an injection medium.

Since the injection medium undergoes adiabatic expansion under reduced pressure, the temperature is lowered and the drying efficiency is improved in that retention is suppressed, but there is a demerit that heat is taken away. Therefore, it is preferable to heat the injection medium to a predetermined temperature.

The injection medium is preferably a nonflammable gas such as nitrogen, argon or air in consideration of heating.

In order to further improve the drying efficiency, the injection medium is more preferably saturated steam or superheated steam. Saturated steam or superheated steam retains a large amount of heat unlike the above-mentioned non-combustible gas, and can supply a large amount of heat energy. Further, as compared with the non-combustible gas, there is no resistance when the volatile component diffuses from the non-dry substance, so that the volatile component can be efficiently removed.

In addition, saturated steam or superheated steam is 1
Since the water content is 00%, most of the water can be collected by the condenser as water. Therefore, it is only necessary to exhaust the gas that could not be condensed, and there is a merit in that the load on the exhaust equipment can be significantly reduced as compared with the non-combustible gas.

The apparatus for producing an electrostatic charge image developing toner used in the method for producing an electrostatic charge image developing toner according to the present invention is capable of depressurizing and irradiating far infrared rays and heating, and is capable of introducing the above injection medium. If so, it can be used without particular limitation. The apparatus for producing a toner for developing an electrostatic image of the present invention is an apparatus for producing a toner by drying wet toner particles obtained by washing and dehydrating polymer particles synthesized in an aqueous medium. A container for containing the wet toner particles, a decompression unit for decompressing the container, a heating irradiation unit for irradiating the wet toner particles with far infrared rays, and a heating unit for heating the wet toner. Specifically, an apparatus for producing an electrostatic charge image developing toner having a mode as shown in FIG. 1 can be exemplified.

As shown in FIG. 1, wet toner particles are supplied into a container 1 having an inverted conical shape as a container for containing wet toner particles, and decompression, far infrared ray irradiation, and heat treatment are performed. Inside the container, a stirring central shaft 3 that can be driven by a drive motor 2 extends in the longitudinal direction of the container center, and a ribbon blade 4 having a single spiral structure is provided around the stirring central shaft 3.

By rotating the ribbon blades 4, the toner can be repeatedly stirred and dispersed while being lifted from the lower side to the upper side, so that the raw materials in the container can be efficiently stirred and mixed throughout.

The heating surface (heat transfer surface) inside the container is
The glass lining is applied, and the above-mentioned particles made of the far-infrared radiation material are baked on the glass lining, and this serves as a far-infrared radiation body as far-infrared radiation means. Specifically, the shape is as shown in (a) and (b) of FIG.
It has a container inner surface 17, a glass layer 20, and far-infrared emitting material particles 21 baked on the glass layer surface. In the present invention, from the viewpoint of toner adhesion, the shape shown in FIG. 2 (b) having a flat surface is preferably used, but the shape is not limited thereto. When the heat source is supplied into the jacket and the inner surface is heated, the baked layer becomes a far infrared radiator. Furthermore, since there is a conventional heat transfer effect, direct heating by radiation and indirect heating from the heat transfer surface are used together, which is very efficient.

Further, the far infrared ray emitting means is not limited to this, and a far infrared ray radiator may be attached above the toner surface in the container (however, at a position where it does not interfere with the stirring blade).
It may be combined with the above-mentioned radiation from the far-infrared radiation material particle baking layer.

Further, as shown in FIG. 1, a raw material supply port 7 for supplying wet toner particles is provided on the upper part of the container, and a bag filter 8 is provided in an exhaust path for reducing the pressure in the container.
Next, the condenser 9 is connected.

As shown in FIG. 1, a jacket 10 is provided around the above-mentioned container so that the temperature in the container can be appropriately controlled and heat treatment can be performed at a desired temperature. . Therefore, the outer wall of the container and the jacket 10
A gap is formed between the inner wall and the inner wall. In order to allow superheated steam or cooling water to pass through this gap, the jacket can be supplied with hot water or steam or cooling water produced in the hot water tank 11, and at the same time
A discharge route for steam and cooling water is also provided.

Further, the decompression in the container is performed by the decompression pump 12 as a decompression means from the exhaust port to the bag filter 8,
This is performed by exhausting the injection medium mixed with the volatile component from the toner in the container through the condenser 9.
As shown in FIG. 1, the inside of the bag filter 8 is divided into two upper and lower chambers by a partition plate 13. And
A tubular filter cloth 14 is suspended below the partition plate, and an exhaust path connected to the condenser 9 is provided above the partition plate, and a backwash nozzle is located above the center of the filter cloth 14. 15 are arranged. The backwash nozzle 15 is for jetting nitrogen, air, saturated steam, or superheated steam intermittently to backwash the filter cloth 14.

When supplying the injection medium into the container,
The supply source of water vapor is not particularly limited, but in general, it is often supplied from a boiler generator, and nitrogen, air and the like are supplied from the generators, respectively. After passing through the injection medium flow meter 5 and being heated by the injection medium heater 16, it is decompressed to a degree close to the operating decompression degree by the expansion tank 18, and the device is distributed from the lower part of the device through the dispersion plate 19 for uniformly dispersing the injection medium. Is evenly supplied inside. The temperature of the injection medium is measured by the injection medium thermometer 6 in the path after passing through the expansion tank 18.

Further, the method of changing the injection medium to the depressurized state is not limited to the above-mentioned method, and for example, instead of installing the expansion tank 18, the pipe diameter may be increased.

By providing the injection medium charging means for uniformly ejecting the injection medium from below, it is possible to prevent the toner from blocking at the lower part of the apparatus. The injection medium supplied into the container by the injection medium charging means becomes vapor mixed with the volatile components from the toner, passes through the bag filter 8, and is condensed and recovered by the next condenser 9.
The vapor that cannot be condensed passes through the decompression pump 12 and is discharged to the outside of the system. When air / nitrogen is used as the injection medium, it is a non-condensable gas, so it is necessary to exhaust as much as it is input, but in the case of saturated steam or superheated steam, it can be recovered as water by a condenser, so it is recovered. Exhaust as much as you could not. As a result, the capacity of the pressure reducing pump can be small as described above.

As the apparatus for producing the electrostatic image developing toner preferably used in the present invention, in addition to the apparatus used in the embodiment shown in FIG. 1, a Nauter mixer (manufactured by Hosokawa Micron Co., Ltd.),
Far-infrared rays such as those mentioned above in a ribocorn mixer (Okawara Seisakusho), a PV mixer (Kanko Pantech), a vacuum stir-dryer Inox system (Pawreck), an SV mixer (Kanko Pantech), etc. It is also possible to substitute by providing an irradiation means.

The polymer particles synthesized in the aqueous medium used in the method for producing the toner for developing an electrostatic image of the present invention are prepared by suspension polymerization or in a liquid containing an emulsion of necessary additives. It can be manufactured by a method in which a monomer is emulsion-polymerized to produce fine resin particles or colorant particles containing a colorant therein, and then an organic solvent, a coagulant and the like are added and associated. Here, the term "association" means that a plurality of resin particles and colorant particles are fused. In addition, in the present invention, the “aqueous medium” refers to one containing at least 50% by mass of water.

The method for producing polymer particles by the suspension polymerization method is not particularly limited, but the following production method can be used. That is, a colorant in the polymerizable monomer as the binder resin component and a release agent if necessary,
Various constituent materials such as a charge control agent and a polymerization initiator are added, and various constituent materials are dissolved or dispersed in the polymerizable monomer with a homogenizer, a sand mill, a sand grinder, an ultrasonic disperser or the like. The polymerizable monomer in which these various constituent materials are dissolved or dispersed is dispersed in an oil droplet of a desired size as a toner in a water-based medium containing a dispersion stabilizer by using a homomixer or a homogenizer. After that, it is transferred to a reaction device having a stirring mechanism and heated to advance the polymerization reaction to obtain polymer particles. After the completion of the reaction, the dispersion stabilizer is removed, and the toner is washed and dehydrated by filtration to obtain wet toner particles.

Further, as a method for producing the polymer particles in the present invention, there can be mentioned a method of adjusting the resin particles by fusing them in an aqueous medium. This method is not particularly limited, but for example, Japanese Patent Laid-Open No. 5-26
The methods described in JP-A-5252, JP-A-6-329947 and JP-A-9-15904 can be mentioned. That is, a method of associating a plurality of resin particles composed of a resin and a colorant and the like, particularly when the resin particles in an aqueous medium are dispersed using an emulsifier, and then salted out by adding an aggregating agent having a critical aggregation concentration or more At the same time, polymer particles are obtained by a method such as heat fusion at a temperature not lower than the glass transition temperature of the formed polymer itself. The wet toner particles according to the present invention can be formed by heating and drying the polymer particles after filtration and washing, or by heating and drying in a fluid state in a water-containing state. Here, an organic solvent infinitely soluble in water may be added at the same time as the coagulant.

In the present invention, wet toner particles obtained by a so-called seed polymerization method, in which a monomer is further adsorbed on the polymer particles once obtained and then polymerization is performed using a polymerization initiator, are also included in the present invention. It can be used suitably.

Examples of the polymerizable monomer that can be used for the polymer particles include styrene-based monomers such as styrene, o (m-, p-)-methylstyrene, m (p-)-ethylstyrene; ) Methyl acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, (meth) (Meth) acrylic acid ester-based monomers such as behenyl acrylate, 2-ethylhexyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, and diethylaminoethyl (meth) acrylate; butadiene, isoprene, cyclohexene, (meth ) Vinyl monomers such as acrylonitrile and acrylic acid amide are preferably used. In addition, two or more kinds may be preferably used in combination, if necessary.

In the present invention, it is particularly preferable to add a polar resin in addition to the outer shell resin in order to encapsulate the low softening point substance in the outer shell resin. As the polar resin used in the present invention, a copolymer of styrene and (meth) acrylic acid, a maleic acid copolymer, a saturated polyester resin, or an epoxy resin is preferably used. It is particularly preferable that the polar resin does not contain an unsaturated group capable of reacting with the shell resin or the polymerizable monomer in the molecule. In the case of containing a polar resin having an unsaturated group, a crosslinking reaction occurs with the polymerizable monomer forming the outer shell resin layer, and when the toner obtained by the production method of the present invention is used as a full-color toner, This is not preferable because it has a high molecular weight and is disadvantageous for color mixing of four-color toner.

The low softening point substance used in the present invention is preferably a compound having a main component maximum peak value measured in accordance with ASTM D3418-8 of 40 to 90 ° C. When the maximum peak is lower than 40 ° C., the self-aggregating force of the low softening point substance becomes weak, resulting in weak high temperature offset resistance, which is not preferable when the toner to be obtained is a full color toner. On the other hand, if the maximum peak exceeds 90 ° C., the fixing temperature becomes high, and it becomes difficult to properly smooth the surface of the fixed image, which is not preferable from the viewpoint of mixability.
Further, when a toner is obtained by a direct polymerization method, the temperature of the maximum peak value is high because granulation and polymerization are carried out in an aqueous system, and a low softening point substance mainly precipitates during granulation, which hinders the suspension system. Therefore, it is not preferable. Specifically, a releasing agent such as paraffin wax, polyolefin wax, Fischer-Ropish wax, amide wax, higher fatty acid, ester wax and derivatives thereof or graft / block compounds thereof can be used.

As the colorant used in the present invention, carbon black as a black colorant, a magnetic substance, and a black / toner color-adjusted yellow / magenta / cyan colorant are used.

The present inventors have found that the magnetic substance more efficiently absorbs electromagnetic waves in the far infrared region. Therefore, in the method for producing a toner for developing an electrostatic charge image of the present invention, when a toner is produced by using polymer particles containing a magnetic material as a material to be dried, irradiation with far infrared rays can further improve the quality of the product. It is possible to raise the temperature and further improve the drying efficiency.

The magnetic material used in the method for producing a toner of the present invention may contain elements such as phosphorus, cobalt, nickel, copper, magnesium, manganese, aluminum and silicon. Further, the magnetic substance is mainly composed of iron oxide such as triiron tetraoxide and γ-iron oxide, and these may be used alone or in combination of two or more. The BET specific surface area of these magnetic materials by the nitrogen adsorption method is preferably 2 to 30 m.
² / g, especially 3 to 28 m ² / g, and Mohs hardness of 5 to 7
Are preferred. The specific surface area is according to the BET method, the specific surface measuring device Autosoap 1 (made by Yuasa Ionics)
Nitrogen gas is adsorbed on the sample surface using, and the specific surface area is calculated using the BET multipoint method.

The shape of the magnetic material is polyhedron, octahedron,
There are hexahedrons, spheres, needles, scales, etc., but polyhedrons, 8
Those having less anisotropy such as a tetrahedron, a hexahedron, and a sphere are preferable for increasing the image density. The shape of these magnetic materials is SE
It can be confirmed by M or the like. The volume average particle diameter of the magnetic material is preferably 0.05 to 0.4 μm, more preferably 0.1 to 0.3 μm. When the volume average particle size is less than 0.05 μm, the blackness is significantly reduced,
As a coloring agent for black-and-white toner, the coloring power is insufficient, and the aggregation of the magnetic materials becomes strong, so that the dispersibility tends to deteriorate. Further, it becomes very difficult to perform the uniformity treatment on the surface of the magnetic body. On the other hand, the volume average particle size is 0.4μ
When it exceeds m, the coloring power becomes insufficient as in the case of general coloring agents. In addition, particularly when used as a colorant for a toner having a small particle diameter, it is stochastically difficult to uniformly disperse the magnetic material in each toner, and the dispersibility is apt to deteriorate.

The magnetic material used in the present invention preferably has a number average variation coefficient of 35 or less. The fact that the number average variation coefficient is larger than 35 means that the particle size distribution of the magnetic material is wide. When such a magnetic material is used, the uniformity of the treatment on the surface of the magnetic material tends to be poor, and the dispersibility in the toner tends to deteriorate.

The number average variation coefficient of the magnetic material is defined as that obtained by the following equation (1).

[0073]

[Equation 1] As the yellow colorant, condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes,
Compounds represented by methine compounds and allylamide compounds are used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83,
93, 94, 95, 109, 110, 111, 128,
129, 147, 168 and the like are preferably used.

As the magenta colorant, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, perylene compounds and the like are used. 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 preferable.

As the cyan colorant, a copper phthalocyanine compound and its derivative, an anthraquinone compound, a basic dye lake compound 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 and the like can be used particularly preferably.

These colorants may be used alone or in combination, and may be used in the form of solid solution. The colorant of the present invention is selected in terms of hue angle, saturation, brightness, weather resistance, OHP transparency, and dispersibility in toner. The colorant is added in an amount of 1 to 20 parts by mass based on 100 parts by mass of the binder resin component.

When a magnetic substance is used as the black colorant, unlike other colorants, it is used by adding 40 to 150 parts by mass to 100 parts by mass of the binder resin component.

The charge control agent used in the present invention includes
Known charge agents can be used, but a charge control agent that is colorless and has a high toner charging speed and that can stably maintain a constant charge amount is preferable. Further, when the direct polymerization method is used in the present invention, a charge control agent having no polymerization inhibitory property and having no solubilized product in an aqueous system is particularly preferable. Specifically, negative compounds such as salicylic acid, naphthoic acid, metal compounds of dicarboxylic acid, sulfonic acid, polymer compounds having carboxylic acid in the side chain, boron compound, urea compound, silicon compound, currys arene, etc. are used. As a positive system, a quaternary ammonium salt, a polymer type compound having the quaternary ammonium salt in its side chain, a guanidine compound, an imidazole compound and the like are preferably used. The charge control agent is preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the binder resin component.

However, the addition of the charge control agent is not essential in the present invention, and when the two-component developing method is used, the triboelectric charging with the carrier is utilized and the non-magnetic one-component blade coating developing method is used. In the above, the toner does not necessarily need to contain the charge control agent by positively utilizing the triboelectric charging with the blade member or the sleeve member.

Examples of the polymerization initiator which can be used for producing the polymer particles according to the present invention include 2,2'-azobis- (2,4-dimethylvaleronitrile),
2'-azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-
Azo- or diazo-type polymerization initiators such as azobis-4-methoxy-2,4-dimethylvaleronitrile and azobisisobutyronitrile; benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichloro Peroxide type polymerization initiators such as benzoyl peroxide and lauroyl peroxide are used. The amount of the polymerization initiator added varies depending on the desired degree of polymerization, but it is generally used in an amount of 0.5 to 20% by mass based on the polymerizable monomer. Although the type of the polymerization initiator varies slightly depending on the polymerization method, it may be used alone or in combination with reference to the 10-hour half-life temperature.

To control the degree of polymerization, known crosslinking agents, chain transfer agents, polymerization inhibitors and the like may be further added and used.

In the polymer particles according to the present invention, as the dispersant to be used particularly when the suspension polymerization using a dispersant is used, as the dispersant, tricalcium phosphate, magnesium phosphate, phosphoric acid can be used. Aluminum, zinc phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate,
Examples include bentonite, silica, alumina and the like. As organic compounds, polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose,
Ethyl cellulose, sodium salt of carboxymethyl cellulose, polyacrylic acid and its salt, starch and the like can be used by dispersing in an aqueous phase. It is preferable to use 0.2 to 20 parts by mass of these stabilizers per 100 parts by mass of the polymerizable monomer.

When an inorganic compound is used among these stabilizers, a commercially available product may be used as it is, but the inorganic compound may be produced in a dispersion medium in order to obtain fine particles. For example, in the case of tricalcium phosphate, it is advisable to mix the sodium phosphate aqueous solution and the calcium chloride aqueous solution under high stirring.

Further, 0.001 to 0.1 part by mass of a surfactant may be used for finely dispersing these stabilizers. This is for promoting the intended action of the dispersion stabilizer, and specific examples thereof include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate,
Examples thereof include sodium oleate, sodium laurate, potassium stearate, calcium oleate and the like.

The toner of the present invention can be specifically manufactured as follows.

That is, a releasing agent, a colorant, a charge control agent, a polymerization initiator and other additives made of a low softening point substance are added to the polymerizable monomer and uniformly dissolved by a homogenizer, an ultrasonic disperser or the like. Or, the dispersed monomer system, a normal stirrer or clear mix in an aqueous phase containing a dispersion stabilizer,
Disperse with a homomixer, homogenizer, etc. Preferably, the stirring speed and time are adjusted so that the monomer droplets have a desired toner size, and granulation is performed. After that, stirring may be performed to the extent that the particle state is maintained and the particles are prevented from settling due to the action of the dispersion stabilizer. The polymerization temperature is preferably set to 40 ° C. or higher, generally 50 to 90 ° C. for polymerization. In addition, the temperature may be raised in the latter half of the polymerization reaction, and further in the latter half of the reaction or the end of the reaction in order to remove unreacted polymerizable monomers and by-products that may cause odor during toner fixing. The aqueous medium may be partially distilled off later. After completion of the reaction, the produced polymer particles are filtered, washed and dehydrated to be collected as wet toner particles,
The toner is obtained by drying by the far infrared ray irradiation and drying method by heating in the method for producing a toner of the present invention. In the suspension polymerization method, it is usually preferable to use 300 to 3000 parts by mass of water as a dispersion medium with respect to 100 parts by mass of the monomer system.

In the present invention, the toner thus obtained is adjusted to have a glass transition temperature (Tg) of 40 to 75 ° C. When Tg is lower than 40 ° C, problems occur in storage stability of toner and durability stability of toner. On the other hand, when Tg is higher than 75 ° C, fixing point is increased, especially in the case of full color toner. Is poor in color reproducibility due to insufficient color mixing of the toners of each color.
This is not preferable from the viewpoint of high image quality because it tends to significantly reduce the transparency of the P image.

Next, the toner obtained by the method for producing a toner for developing an electrostatic charge image of the present invention preferably has a fine particle size in order to faithfully reproduce finer latent image dots due to the demand for higher image quality. More specifically, a toner having a weight average particle diameter of 4 to 10 μm and a number variation coefficient of less than 35% measured by a Coulter counter is most preferable. With toner of less than 4 μm, a large amount of transfer residual toner is likely to occur on the photoconductor or the intermediate transfer member due to poor transfer efficiency, resulting in fog,
It is not preferable because it causes uneven unevenness of the image due to poor transfer. Further, when the weight average particle diameter of the toner exceeds 10 μm, fusion to the member is apt to occur, and when the number variation coefficient of the toner exceeds 35%, this tendency becomes more serious and becomes a problem. The coefficient of variation of the number of toner particles is defined as being calculated by the following equation (2).

[0089]

[Equation 2] Number variation coefficient = standard deviation of number distribution / number average particle size × 100 (2)

The toner of the present invention contains at least a binder resin component and a colorant, but may contain a releasing agent which is a fixing property improving agent, a charge control agent and the like, if necessary. Furthermore, an external additive composed of inorganic fine particles or organic fine particles may be added to the toner containing the binder resin component and the colorant as main components.

The manufacturing method of the present invention can be applied not only to toner but also to binder resin for toner. The binder resin for a toner in a wet state obtained by various polymerization methods requires a step of removing water, residual polymerizable monomers and other volatile components, like the wet toner particles obtained by the polymerization method. However, the depressurization / far-infrared irradiation / heat treatment described above can be used as the volatile matter removing step.

Examples of the binder resin for toner used in the present invention include vinyl resins, polyester resins, copolymers of vinyl monomers and polyester monomers, etc., but are not particularly limited.

The method of measuring each physical property value used in the present invention will be described below. (1) Method of measuring water content The water content of the wet toner particles in the present invention is determined by the MA40 electronic moisture meter (manufactured by Sartorius Co., Ltd.) by the heating weight loss method at 105 ° C. (2) Measurement of residual amount of polymerizable monomer and other organic volatile substances remaining in toner particles Quantification of residual amount of polymerizable monomer and other organic volatile substance remaining in the toner is determined by toner 0 Acetone 10 g
What was dissolved in g, subjected to an ultrasonic shaker for 30 minutes, allowed to stand for 1 day, and then filtered with a 0.5 μm filter was used. It is measured by the line method. Gas chromatography condition measuring device: HEWLETT PACKARD HP 6890 series Capillary column: (25m × 0.2mm, HP-INNOWAX, film thickness:
0.4 μm) Detector: FID He flow rate 25 ml / min Injection temperature: 200 ° C. Detector temperature: 250 ° C. Column temperature: 50 ° C. to 10 ° C./min for 15 minutes Temperature rise Implanted sample amount: 2 μl (3) Toner particle size distribution Here, the particle size distribution can be measured by various methods, but in the present invention, it is measured using a Coulter counter.

As the measuring device, Coulter Counter TA-II type or Coulter Multisizer II (manufactured by Coulter) is used. As the electrolytic solution, about 1% NaCl aqueous solution is prepared using first-grade sodium chloride. For example, I
SOTON-II (manufactured by Coulter Scientific Japan) can be used. As a measuring method, a surfactant, preferably an alkylbenzene sulfonate, was added as a dispersant to 100 to 150 ml of the electrolytic aqueous solution.
Add 1 to 5 ml, and further add 2 to 20 mg of the measurement sample. The electrolytic solution in which the sample is suspended is about 1 to 3 with an ultrasonic disperser.
Dispersion processing is performed for a minute, and the volume and number of toner are measured by the above-described measuring device using a 100 μm aperture as an aperture to calculate a volume distribution and a number distribution.
Then, the weight-based weight average particle diameter (D4) (the median value of each channel is used as a representative value for each channel) determined from the volume distribution according to the present invention is determined.

[0095]

EXAMPLES The present invention will be specifically described below with reference to examples.

[0096]

Example 1 710 parts by mass of ion-exchanged water contained 0.1 mol / min.
Add 450 parts by mass of liter-Na ₃ PO ₄ aqueous solution to 60
After heating to 0 ° C, the mixture was stirred at 3,500 rpm with CLEARMIX (manufactured by M Technique Co., Ltd.). To this, 68 parts by mass of 1.0 mol / liter-CaCl ₂ aqueous solution was added to obtain an aqueous medium containing Ca ₃ (PO ₄ ) ₂ .

On the other hand, the dispersoid system is as follows. Styrene monomer 175 parts by mass n-butyl acrylate 25 parts by mass C.I. I. Pigment Blue 15: 3 10 parts by mass, saturated polyester 20 parts by mass, metal salicylate compound 3 parts by mass, paraffin wax 30 parts by mass. I. Pigment Blue 15: 3,
A metal salicylate compound and 100 parts by mass of a styrene monomer were dispersed for 3 hours using an attritor (Mitsui Miike Kakoki Co., Ltd.) to obtain a colorant dispersion liquid. Next, the rest of the above formulation was added to the colorant dispersion, heated to 60 ° C., and dissolved and mixed for 30 minutes. 10 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile), which is a polymerization initiator, was dissolved in this to prepare a polymerizable monomer composition.

The above polymerizable monomer composition was put into the above aqueous dispersion medium and granulated for 12 minutes while maintaining the rotation speed. After that, the stirrer was changed from the high speed stirrer to the propeller stirrer, the internal temperature was raised to 80 ° C., and the polymerization was continued at 50 rpm for 8 hours to obtain polymer particles. Then, the internal temperature 80 ℃,
Distillation was carried out for 4 hours under the condition of the apparatus internal pressure of 47.3 kpa. After the completion of distillation, the slurry is cooled, diluted hydrochloric acid is added,
After Ca ₃ (PO ₄ ) ₂ was dissolved, it was filtered, washed with water, and then crushed to obtain wet toner particles having a water content of 23% and a weight average particle diameter of 7.9 μm.

At this point, the amount of polymerizable monomer remaining in the wet toner particles was 720 ppm. The obtained wet toner particles are preliminarily dried by using a flash jet dryer (manufactured by Seishin Enterprise Co., Ltd.) which is an airflow dryer to obtain a water content of 0.3% and a weight average particle diameter of 7.9 μm.
Wet toner particles having a residual amount of polymerizable monomers of 710 ppm were obtained.

The wet toner particles are subjected to far infrared irradiation and heat treatment under reduced pressure using the above-described apparatus for producing an electrostatic charge image developing toner having a container having an effective charging capacity of 100 L as shown in FIG. It was As far-infrared radiation means, as shown in FIG. 2 (b), a glass lining is applied to the heating surface inside the container, and far-infrared radiation material particles composed of Al ₂ O ₃ and Cr ₂ O _{3 are} placed on the glass lining. It was baked and used as a far infrared radiator. When the heating medium was introduced into the jacket, the far-infrared emitting material particles of the far-infrared emitting body were gradually heated and processed so as to serve as a radiation source.

The peak of the emissivity of the far infrared radiator is 1
At 1 μm, the emissivity of the black body was about 0.95.

The reduced pressure treatment was carried out under the following conditions. Stirring speed: 26 rpm Heating temperature: 50 ° C. Decompression degree: 2.0 kpa The product temperature of the toner at the start of the treatment was 23 ° C. After the lapse of 2 hours from the start of the treatment, the temperature of the toner layer was measured and found to be 43 ° C. on average. The treatment time was determined by setting the target amount of the remaining polymerizable monomer to 50 ppm, performing the same treatment in advance with the apparatus configuration and treatment conditions described above, and estimating the time to reach about 50 ppm.

The processing time was set in the same manner in the following examples and comparative examples. The processing time of Example 1 was 5 hours. At the end of the treatment, the water content of the toner was 0.2%, the amount of residual polymerizable monomers was 52 ppm, and the final toner temperature was 48 ° C. on average.

To 100 parts by mass of the obtained toner,
Specific surface area by BET method is 200m ²/ G is hydrophobic
1.5 parts by mass of silica was externally added to obtain a developing toner.

By using this developing toner, LBP204
When 0 (Canon) remodeling machine was used and 3000 images were printed in an environment of 30 ° C./80% RH, excellent images without vertical stripes and roughness were obtained before and after endurance. . The evaluation results are shown in Table 1. (1) The criteria for determining the vertical stripes are as follows. A: No vertical streak has occurred. B: Several vertical stripes occurred. C: A large number of vertical stripes were generated. (2) The criteria for determining the image quality are as follows. A: Very good. B: Although it is slightly shaky from the latter half of the endurance, there is no problem in practical use. C: It is difficult to put it into practical use because it has been rough since the beginning of durability. D: Practically impractical due to severe roughness.

[0106]

Example 2 Nitrogen heated to 50 ° C. was charged at 2.5 m ³ / hr as an injection medium, and the degree of reduced pressure was 3.0 k.
The same apparatus as in Example 1 was used except that pa was used,
Processing was performed using wet toner particles that had been subjected to preliminary heat treatment under the same conditions. The pressure was reduced, the far infrared ray was irradiated, and the heat treatment time was set to 4 hours for the treatment. The product temperature of the toner at the start of the treatment was 23 ° C., and the temperature of the toner layer after 2 hours from the start of the treatment was 44 ° C.

The water content of the toner after the treatment is 0.2%,
The amount of residual polymerizable monomer was 53 ppm, and the final toner temperature was 48 ° C. on average.

The toner thus obtained was used as a developing toner in the same manner as in Example 1 and was evaluated by the same method. As a result, an excellent image without vertical stripes and roughness was obtained before and after durability. . The evaluation results are shown in Table 1.

[0109]

Example 3 Instead of nitrogen, superheated steam at 50 ° C. was charged at 2.5 m ³ / hr and the degree of pressure reduction was 3.3 k.
Processing was performed under the same conditions, using the same wet toner particles and apparatus configuration as in Example 2 except that it was set to pa. The pressure was reduced, the far infrared ray was irradiated, and the heat treatment time was set to 3 hours, and the treatment was performed. The temperature of the toner at the start of processing is 23 ° C.
The temperature of the toner layer after 2 hours from the start of the treatment was 45 ° C. on average.

At the end of the treatment, the water content of the toner is 0.2%,
The amount of residual polymerizable monomer was 51 ppm, and the final toner temperature was 49 ° C.

The toner thus obtained was used as a developing toner in the same manner as in Example 2 and evaluated by the same method. As a result, an excellent image without vertical stripes and roughness was obtained before and after the endurance. . The evaluation results are shown in Table 1.

[0112]

Example 4 720 parts by mass of ion-exchanged water contained 0.1M-N
a ₃ PO ₄ aqueous solution (450 parts by mass), 1N hydrochloric acid (16 parts by mass) were added and heated to 60 ° C., and then 1.0 M-CaCl ₂ aqueous solution (67.7 parts by mass) was added to contain Ca ₃ (PO ₄ ) ₂ . An aqueous medium was obtained.

On the other hand, the dispersoid system is as follows. -Styrene 80 parts by mass-n-butyl acrylate 20 parts by mass-Saturated polyester resin 1 part by mass-Divinylbenzene 0.25 parts by mass-Negatively charge controlling agent 1 part by mass (monoazo dye-based Fe compound) -Magnetic substance 80 parts by mass Parts The above formulation was uniformly dispersed and mixed using a homogenizer. This monomer composition was heated to 60 ° C., and the ester wax (maximum value of endothermic peak in DSC 72
C.) 7 parts by mass are added, mixed and dissolved, and the polymerization initiator 2,
2'-azobis (2,4-dimethylvaleronitrile) 5
Part by mass was dissolved.

The above polymerizable monomer system was charged into the above aqueous medium, and the mixture was mixed at 60 ° C. under N ₂ atmosphere with a TK homomixer (Tokushu Kika Kogyo Co., Ltd.) at 10,000 rpm at 1 rpm.
The mixture was stirred for 5 minutes and granulated. Then, while stirring with a paddle stirring blade, after reacting at 60 ° C for 4 hours, the temperature was raised to 80 ° C,
The reaction was continued for 5 hours to obtain polymer particles. After the reaction was completed, the suspension was cooled, hydrochloric acid was added to dissolve the dispersant at pH 2 or less, and the mixture was filtered and washed with water to obtain wet toner particles having a weight average particle diameter of 7.6 μm. At this point, the water content is 25% and the amount of the polymerizable monomer remaining in the wet toner particles is 800.
It was ppm.

The wet toner particles thus obtained were subjected to preliminary drying by a flash jet dryer, which is an airflow dryer, to obtain a water content of 0.3%, a weight average particle diameter of 7.5 μm, and a residual polymerizable monomer. The amount of the monomer is 790ppm
Wet toner particles were obtained.

The obtained wet toner particles were treated in the same apparatus and conditions as in Example 1. The pressure was reduced, the far infrared ray was irradiated, and the heat treatment time was set to 3.5 hours, and the treatment was performed. The temperature of the toner at the start of processing is 23 ° C.
The temperature of the subsequent toner layer was 49 ° C. on average. After the treatment, the toner has a water content of 0.2%, the amount of remaining polymerizable monomers is 49 ppm, and the final toner temperature is 49.5 ° C. on average.
Met. It can be seen that the magnetic substance contained efficiently absorbed far-infrared rays because the temperature of the product rises quickly and the treatment can be achieved in a short time as a result.

Since the obtained toner contains a magnetic substance and has properties greatly different from those of the toners used in the other Examples and Comparative Examples,
The same evaluation cannot be performed, but with 100 parts by mass of this toner,
BE treated with silica having a primary particle diameter of 12 nm after treatment with hexamethyldisilazane and then with silicone oil
1.0 part by mass of hydrophobic silica fine powder having a T value of 120 m ² / g was mixed with a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) to obtain a developing toner, and then a LBP-1760 (Canon) remodeling machine The developing property, the transfer property, the fixing property, etc. were confirmed by using, but there was no particular problem in terms of performance.

[0118]

[Comparative Example 1] Except that the heating surface inside the container of the apparatus for producing an electrostatic image developing toner is not glass-lined or baked with far-infrared emitting material particles, and is made of general stainless steel. Device configuration and conditions similar to those of No. 1 were used, and reduced pressure and heat treatment were performed using wet toner particles that had been subjected to preliminary heat treatment.

The pressure was reduced and the heat treatment time was set to 7 hours for the treatment. The temperature of the toner at the start of the treatment was 23 ° C., and the temperature of the toner layer 2 hours after the start of the treatment was 35 ° C. on average. Moisture content of toner at the end of processing is 0.2
%, The amount of residual polymerizable monomer was 52 ppm, and the final temperature of the toner layer was 47 ° C. on average.

The toner thus obtained was used as a developing toner in the same manner as in Example 1, and the image formation was evaluated in the same manner as in Example 1. As a result, vertical stripes were observed immediately after image formation was started. In the latter half of the endurance, many vertical stripes were generated and the image was severely rough, which was a level of difficulty for practical use. The evaluation results are shown in Table 1.

[0121]

[Embodiment 5] The heating temperature is 60 ° C and the degree of vacuum is 2.2 kpa.
Other than the above, the same apparatus configuration and conditions as in Example 1 and the same wet toner particles were used to perform the pressure reduction and heat treatment.

The pressure was reduced and the heat treatment time was set to 3.5 hours for the treatment. The temperature of the toner at the start of processing is 23
The temperature of the toner layer after 2 hours from the start of the treatment is
The average temperature was 52 ° C. At the end of the treatment, the toner was mostly agglomerated. The water content was 0.1%, the amount of residual polymerizable monomer was 50 ppm, and the final toner temperature was 56 ° C.

The toner thus obtained was used as a developing toner in the same manner as in Example 1, and the same image development evaluation as in Example 1 was carried out. However, several vertical streaks occurred. In addition, although there was no problem in practical use, the image was slightly harsh in the latter half of the durability test. The evaluation results are shown in Table 1.

[0124]

[Example 6] The wet toner particles obtained after washing, dehydration and crushing of Example 1 are preliminarily dried by using a flash jet dryer, which is an airflow dryer, under conditions different from those of Example 1. , Water content 6%, weight average particle size 7.
Wet toner particles having a diameter of 9 μm and a residual amount of polymerizable monomers of 715 ppm were obtained.

The obtained wet toner particles were subjected to the same apparatus constitution and conditions as in Example 1 (provided that the maximum decompression degree was 4.7 kpa from 0 to 15 minutes, and the decompression degree gradually increased after 15 minutes. After that, it was stabilized at 2.0 kpa.).

Decompression, far infrared irradiation, and heat treatment time are 5.
The processing was performed after setting for 5 hours. The temperature of the toner at the start of the treatment was 23 ° C., and the temperature of the toner layer 2 hours after the start of the treatment was 40 ° C. on average. The toner obtained after the treatment had a water content of 0.2% and a residual polymerizable monomer content of 51.
ppm, final toner temperature was 48 ° C.

The toner thus obtained was used as a developing toner in the same manner as in Example 1, and the same image evaluation as in Example 1 was carried out. However, several vertical streaks occurred. As for the image, an excellent image without roughness was obtained. The evaluation results are shown in Table 1.

[0128]

[Table 1]

[0129]

According to the present invention, it is possible to provide a method for producing a toner for developing an electrostatic charge image, which uniformly removes volatile components present in toner particles synthesized in an aqueous medium in a short time. . Further, the present invention provides a method for producing a toner for developing an electrostatic charge image and an apparatus for producing the toner, which can obtain a high-quality image free from image defects caused by residual volatile components and image defects caused by thermally deteriorated toner. You can

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of an apparatus for producing an electrostatic charge image developing toner used in the present invention.

FIG. 2 (a) is a schematic view showing a far infrared radiator used in the present invention. (B) It is a schematic diagram showing a far-infrared radiator used for the present invention.

[Explanation of symbols] 1 container 2 drive motor 3 Stirring center axis 4 ribbon wings 5 Injection medium flow meter 6 Injection medium thermometer 7 Raw material supply port 8 bag filters 9 condenser 10 jacket 11 Hot water tank 12 Decompression pump 13 partition boards 14 filter cloth 15 Backwash nozzle 16 Injection medium heater 17 Inner surface of container 18 expansion tank 19 Dispersion board 20 glass layers 21 Far-infrared radiation material particles

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoshinori Tsuji             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F-term (reference) 2H005 AA02 AB06 AB09

Claims (11)

[Claims] 1. An electrostatic charge image having a step of obtaining toner by heating wet toner particles obtained by washing and dehydrating polymer particles synthesized in an aqueous medium, under reduced pressure and irradiation with far infrared rays. Method for producing developing toner. 2. The method for producing an electrostatic charge image developing toner according to claim 1, wherein the wet toner particles obtained after washing and dehydration have a water content of 3.0% or less. 3. The method for producing a toner for developing an electrostatic charge image according to claim 1, wherein the far infrared ray irradiation and heating are performed so that the temperature of the toner is 60 ° C. or lower. 4. The method for producing an electrostatic charge image developing toner according to claim 1, wherein an injection medium is charged under the reduced pressure. 5. The method for producing an electrostatic image developing toner according to claim 1, wherein the injection medium is saturated steam or superheated steam. 6. The method for producing a toner for developing an electrostatic charge image according to claim 1, wherein the polymer particles synthesized in the aqueous medium contain a magnetic material. . 7. The far-infrared ray is obtained from a far-infrared radiator having an emissivity peak in a wavelength range of 4 to 20 μm. A method for producing the electrostatic charge image developing toner as described above. 8. An apparatus for producing toner by drying wet toner particles obtained by washing and dehydrating polymer particles synthesized in an aqueous medium, the container containing the wet toner particles. And a depressurizing unit for depressurizing the container, a far infrared ray irradiating unit for irradiating the wet toner particles with far infrared rays, and a heating unit for heating the wet toner particles. Manufacturing equipment. 9. The apparatus for producing an electrostatic image developing toner according to claim 8, further comprising an injection medium charging means for charging an injection medium into the container whose pressure has been reduced by the pressure reducing means. 10. The apparatus for producing an electrostatic charge image developing toner according to claim 8, wherein the injection medium is saturated steam or superheated steam. 11. The far-infrared irradiation means is a far-infrared radiator having an emissivity peak within a wavelength range of 4 to 20 μm, according to any one of claims 8 to 10. Equipment for manufacturing toner for electrostatic image development.