WO1997001131A1

WO1997001131A1 - Process for producing toner for developing electrostatically charged images

Info

Publication number: WO1997001131A1
Application number: PCT/JP1996/001714
Authority: WO
Inventors: Jun Hasegawa; Jun Sakai; Makoto Watanabe; Fumio Yamada; Tokudai Ogawa
Original assignee: Nippon Zeon Co., Ltd.
Priority date: 1995-06-21
Filing date: 1996-06-20
Publication date: 1997-01-09
Also published as: KR100391838B1; JP3195362B2; EP0834779B1; EP0834779A4; DE69634298D1; KR19990028254A; EP0834779A1

Abstract

A process for producing a toner for developing electrostatically charged images which comprises suspension-polymerizing a monomer composition at least comprising a polymerizable monomer and a colorant in an aqueous dispersion medium containing a dispersant to form colored polymer particles, characterized by comprising the following two steps: (1) the first step of forming colored polymer particles as the core component by suspension-polymerizing a monomer composition for the core component comprising at least one core-forming monomer giving a polymer having a glass transition temperature of 80 °C or below and a colorant in an aqueous dispersion medium until the conversion of the monomer into polymer reaches 80 % or above, and (2) the second step of forming a polymer layer as the shell on the surface of each colored polymer particle as the core component by adding at least one shell-forming monomer giving a polymer having a glass transition temperature higher than that of the polymer forming the core or a shell-forming monomer composition containing such a monomer and a water-soluble radical polymerization initiator to the reaction system containing the colored polymer particles as the core component and subjecting the obtained mixture to polymerization, and thereby producing encapsulated colored polymer particles having a core-shell structure comprising 40 to 99 wt% of the core component and 1 to 60 wt% of the shell component. The toner thus produced has a low fixing temperature, a good transparency of the images formed on an OHP film, and an excellent shelf stability.

Description

T / P96 / 01714 Description Manufacturing method of toner for developing electrostatic images

The present invention relates to a method for manufacturing a toner for developing an electrostatic image, and more particularly, to a method for developing an electrostatic image formed by electrophotography, electrostatic recording, or the like. It relates to a manufacturing method of the. Background art

Conventionally, an electric latent image formed by an electrophotographic device or an electrostatic recording device is first developed with toner, and then the formed toner image is transferred to paper or the like as necessary. After being transferred onto the material, it is fixed by various methods such as heating, pressing, and solvent vapor.

Conventionally, toners are generally prepared by melt-mixing a colorant, a charge controlling agent, an anti-offset agent, and the like in a thermoplastic resin, uniformly dispersing the mixture into a composition, and then pulverizing the composition. It has been manufactured by classifying. According to this production method (that is, the pulverization method), a toner having excellent properties to some extent can be produced, but the selection of a toner material is limited. For example, the composition produced by the above-mentioned melt mixing must be capable of being pulverized and classified with an economically usable device. From this requirement, the melt-blended composition must be sufficiently brittle. Therefore, when the above composition is actually pulverized into particles, a wide range of particle size distribution is likely to be formed, and it is intended to obtain a copied image having good resolution and gradation. For example, fine powder having a particle size of 5 / m or less and coarse powder having a particle size of 20 ^ m or more must be removed by classification, and the yield is extremely low. Disadvantage.

Further, in this pulverization method, it is difficult to uniformly disperse solid fine particles such as a coloring agent, a charge control agent, and an offset preventing agent in a thermoplastic resin, and depending on the dispersion state of these solid fine particles. It causes an increase in fog and a decrease in image density. The non-uniform dispersion of these solid fine particles in the pulverization method greatly affects the fluidity, triboelectricity, and the like of the toner, and affects the properties of the toner such as developability and durability. Therefore, in the pulverization method, sufficient care must be taken to uniformly disperse these solid fine particles.

In recent years, in order to overcome the problems in these pulverization methods, a method for producing a toner by suspension polymerization has been proposed. In this suspension polymerization method, a monomer composition obtained by uniformly dissolving or dispersing a polymerizable monomer, a colorant, a charge control agent, an offset inhibitor, a polymerization initiator, and the like is dispersed. It was poured into water containing a stabilizer or an aqueous dispersion medium mainly composed of water, dispersed using a mixing device having high shearing force, and granulated as monomer droplets of the monomer composition. Later, it is polymerized to form toner particles (ie, polymerized toner).

In the suspension polymerization method, a coloring agent, a charge control agent, an offset preventing agent, and the like are added to and dispersed in a low-viscosity liquid monomer. Sufficient dispersibility is ensured. In addition, the suspension polymerization method is generally more economical than the pulverization method because toner particles having a desired particle size can be obtained in a yield of 90% or more. By adopting the suspension polymerization method in this way, the above-mentioned problems of the pulverization method can be solved, and the resolution can be improved based on the extremely sharp particle size distribution of the polymer particles and the good electrical characteristics. Thus, it has become possible to economically produce toner having excellent image quality characteristics such as capri. Recently, power consumption has been reduced in electrophotographic copiers and printers that use toner. Among the electrophotographic processes, a process that consumes energy is a so-called fixing process in which toner is transferred from a photoreceptor onto a transfer material such as paper and then fixed. Generally, a heat roll of 150 ° C or higher is used for fixing, and electric power is used as an energy source. Reducing the temperature of the hot roll is required from the viewpoint of energy saving. To this end, it is necessary to lower the fixing temperature of the toner.

In the design of toner, to meet the demands of copiers and the like, it is necessary to lower the glass transition temperature of the toner, but if the glass transition temperature is lowered, the toner can be blown during storage or in the toner box. This causes agglomeration, resulting in agglomerates, and so-called poor storage toner.

On the other hand, in the case of electrophotographic color toners, color images are often used for OHP sheets for presentations at various meetings in recent years, and color toners Therefore, it is required to have excellent OHP transparency. In order to satisfy OHP transparency, it is essential that the toner is uniformly melted on the OHP sheet.To achieve this, the melt viscosity around the fixing temperature of the toner must be reduced to the conventional value. It is necessary to design lower. Methods for lowering the melt viscosity of toner include lowering the molecular weight and lowering the glass transition temperature compared to conventional binder resins for toner. However, it easily causes blocking, resulting in poor storage stability.

As described above, there is an inverse correlation between the method of lowering the fixing temperature of the toner and improving the 0 HP transmittance and the storability of the toner. 1 JP

Four

As a method for solving the problem, a so-called capsule-type toner has been proposed in which the toner particles are coated with a polymer having a high glass transition temperature and the storage stability is solved.

Conventionally, as a method of manufacturing a capsule type toner, for example, Japanese Patent Application Laid-Open No. 60-173552 discloses a jet mill device which uses a jet mill device to apply There has been proposed a method of forming a coating layer comprising a coloring agent, magnetic particles, or a conductive agent and a binder resin. However, this method is not applicable when the glass transition temperature of the nuclear particles is low, because the nuclear particles themselves aggregate.

Japanese Unexamined Patent Publication No. 2-2595757 discloses that a polymer prepared by suspension polymerization in a solution obtained by dissolving a polymer for encapsulation, a charge controlling agent and a release agent in an organic solvent. After adding the cross-linked toner particles, a poor solvent is added to form a coating of a force-pressing polymer containing a charge controlling agent and a release agent on the surface of the cross-linked toner particles. A method has been proposed. However, in this production method, the solubility of the encapsulating polymer is reduced by dropping a poor solvent, and the polymer is precipitated on the surface of the crosslinked toner particles. There is a problem that is not.

Japanese Patent Application Laid-Open No. 57-45558 discloses a technique in which core particles formed by polymerization are mixed and dispersed in a 1 to 40% by weight aqueous solution of a latex, and then the aqueous solution is dissolved. A method for producing a toner for developing an electrostatic image has been proposed in which an inorganic salt is added to form a coating layer of fine particles obtained by emulsion polymerization on the surface of core particles. However, this method has a drawback that the charging characteristics are largely dependent on the environment due to the effect of surfactants and inorganic salts remaining on the fine particles, and the charging is reduced particularly under high-temperature and high-humidity conditions. . Disclosure of the invention

An object of the present invention is to provide a method for producing a toner for developing an electrostatic image, which has a low fixing temperature and good OHP permeability, and has excellent storage stability.

The present inventors have conducted intensive studies to overcome the problems of the prior art, and as a result, in a method of producing toner particles by a suspension polymerization method, first, a glass transition temperature was 80 ° C. The following polymer particles are formed as core components (core particles), and then a monomer that forms a polymer having a higher glass transition temperature than the polymer of the core component is added to carry out the polymerization reaction. By continuously forming a coating layer of a shell component having a high glass transition temperature on the surface of the core component, a capsule-type toner was produced. In addition to having high OHP permeability, it was found that the presence of the seal component prevented blocking and was excellent in storage stability. A coloring agent is contained in the core component to form colored polymer particles.

Further, in producing a capsule-type toner by a suspension polymerization method, a monomer for shell component or a monomer thereof is added to a suspension polymerization reaction system in the presence of colored polymer particles as a core component. A monomer component composition for a shell component containing a polymer and a water-soluble radical initiator are added to carry out a polymerization reaction, and the surface of the core component polymer particles is coated with a polymer that becomes a shell component. It has been found that the method of forming the layer is preferred.

Furthermore, (1) the monomer for shell component or the monomer composition for shell component containing the monomer is more number-averaged in the reaction system than colored polymer particles of the core component. The polymerization reaction is carried out by adding it as an aqueous suspension of small droplets, or (2) the solubility in water at 20 ° C as a monomer for the seal component is 0. If less than 1% by weight of monomer is used, Along with the monomer for a shell component or the monomer composition for a shell component containing the monomer, an organic solvent having a solubility in water at 20 ° C of 5% by weight or more is added. It has been found that by performing polymerization, it is possible to efficiently form a coating layer of a polymer which becomes a seal component.

The present invention has been completed based on these findings. In the present invention, the capsule-type toner or the capsule-type colored polymer particles refer to a coating layer of a shell-forming polymer (that is, a shell component) formed on the surface of a core of the colored polymer particles (that is, a core component). Colored polymer particles having a core-shell structure.

Thus, according to the present invention, a monomer composition containing at least a polymerizable monomer and a colorant is suspension-polymerized in an aqueous dispersion medium containing a dispersant. Thus, in the method for producing a toner for developing an electrostatic image composed of colored polymer particles,

(1) A monomer for a core component containing at least one kind of a monomer for a core component and a colorant, which forms a polymer having a glass transition temperature of 80 ° C or lower in an aqueous dispersion medium. A first step of subjecting the composition to suspension polymerization until the polymerization conversion of the monomer becomes 80% or more to form colored polymer particles serving as a core component; and

(2) In the reaction system containing the colored polymer particles serving as the core component, at least one kind of shell component for forming a polymer having a glass transition temperature higher than the glass transition temperature of the polymer of the core component. The monomer or the monomer composition for a shell component containing the monomer and a water-soluble radical initiator are added to carry out a polymerization reaction, and the surface of the colored polymer particles serving as the core component is added to the surface of the polymer. At least two steps in the second step of forming a polymer coating layer serving as a shell component are composed of a core component of 40 to 99% by weight and a shell component of 1 to 60% by weight. Core-shell structured force-cell-type colored polymerization Provided is a method for producing a toner for developing an electrostatic image, characterized by producing body particles.

Further, according to the present invention, in the second step, the glass transition temperature higher than the glass transition temperature of the polymer of the core component is added to the reaction system containing the colored polymer particles serving as the core component. At least one monomer for a shell component or a monomer composition for a shell component containing the monomer is formed from at least one colored polymer particle serving as a core component. Is added as an aqueous suspension of droplets having a small number average particle diameter, and a polymerization reaction is carried out to form a coating layer of a polymer serving as a shell component on the surface of the colored polymer particles serving as a core component. And a method for producing a toner for developing an electrostatic image, characterized by the following.

Further, according to the present invention, in the second step, the glass transition temperature higher than the glass transition temperature of the polymer of the core component is added to the reaction system containing the colored polymer particles serving as the core component. At least one monomer for the shell component or a monomer composition for the shell component containing the monomer having a solubility in water at 20 ° C. of at least 5 which forms a polymer at a temperature. An organic solvent of at least 10% by weight is added to carry out a polymerization reaction to form a coating layer of a polymer serving as a shell component on the surface of the colored polymer particles serving as a core component. A method for manufacturing a toner for developing a charge image is provided.

According to the present invention, there is provided a toner for developing an electrostatic image obtained by the above-described manufacturing method.

According to the present invention, there is provided an image forming apparatus including a storage unit for storing the electrostatic image developing toner obtained by the above-described manufacturing method. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram showing a housing means for housing the toner for developing an electrostatic image of the present invention. FIG. 3 is a sectional view of the image forming apparatus obtained. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail.

Manufacturing method of toner

The toner for developing an electrostatic image of the present invention is produced by employing a suspension polymerization method. In the suspension polymerization method, usually, a monomer solution containing at least a polymerizable monomer and a colorant is added to an aqueous dispersion medium containing a dispersant, followed by suspension polymerization. To produce colored polymer particles. More specifically, a colorant, a radical polymerization initiator, a charge control agent, and other additives are added to a vinyl monomer, and the mixture is uniformly dispersed with a ball mill or the like ( That is, a monomer composition) was prepared, and then the mixed solution was poured into an aqueous dispersion medium, dispersed using a mixing device having high shearing force, and granulated into fine droplets. Usually, the suspension polymerization is carried out at a temperature of 30 to 200 ° C.

In the present invention, a multi-stage polymerization method is employed for producing a capsule type toner by a suspension polymerization method. That is, a monomer composition containing at least a polymerizable monomer and a coloring agent is added to an aqueous dispersion medium containing a dispersing agent, and suspension polymerization is carried out to obtain a colored pigment. In a method for producing a toner for developing an electrostatic image composed of coalesced particles, suspension polymerization is carried out in at least the following two steps.

(1) A monomer for a core component containing at least one monomer for a core component and a colorant to form a polymer having a glass transition temperature of 80 ° C or lower in an aqueous dispersion medium. A first step of subjecting the composition to suspension polymerization until the polymerization conversion of the monomer becomes 80% or more to form colored polymer particles serving as a core component; and (2) At least one kind of shell component that forms a polymer having a glass transition temperature higher than the glass transition temperature of the polymer of the core component in the reaction system containing the colored polymer particles serving as the core component. Polymerizable monomer or a monomer composition for a shell component containing the monomer and a water-soluble radial initiator are added, and a polymerization reaction is carried out to obtain colored polymer particles serving as a core component A second step of forming a polymer coating layer serving as a shell component on the surface of the polymer.

By at least two of these steps, force-cell-type colored polymer particles having a core seal structure composed of 40 to 99% by weight of a core component and 1 to 60% by weight of a sealer component are produced. An additional step may be present as long as the capsule-type colored polymer particles having the core shell structure are formed.

As the second step, at least a polymer having a glass transition temperature higher than the glass transition temperature of the polymer of the core component is formed in the reaction system containing the colored polymer particles serving as the core component. A monomer for a shell component or a monomer composition for a shell component containing the monomer is converted into a droplet having a smaller number average particle diameter than the colored polymer particles serving as a core component. A step of forming a coating layer of a polymer serving as a shell component on the surface of the colored polymer particles serving as a core component by adding the resultant to an aqueous suspension and performing a polymerization reaction can be employed. .

Alternatively, as the second step, a small amount of a polymer having a glass transition temperature higher than the glass transition temperature of the polymer of the core component is formed in the reaction system containing the colored polymer particles serving as the core component. Particularly, together with a kind of monomer for shell component or a monomer composition for shell component containing the monomer, an organic compound having a solubility in water at 20 ° C of 5% by weight or more is 5% by weight or more. A step of adding a solvent and performing a polymerization reaction to form a coating layer of a polymer serving as a shell component on the surface of the colored polymer particles serving as a core component can be employed. You.

Here, the glass transition temperature (T g) of the polymer is a calculated value (referred to as calculated T g) calculated according to the type of the monomer used and the usage ratio. When one kind of monomer is used, the Tg of a homopolymer formed from the monomer is defined as the Tg of the polymer in the present invention. For example, since Tg of polystyrene is 100 ° C., when styrene is used alone as a monomer, the monomer has a Tg of 100%. It is said to form a union. If two or more monomers are used and the resulting polymer is a copolymer, the Tg of the copolymer is calculated according to the type of monomer used and the proportion used. For example, when 60% by weight of styrene and 40% by weight of n-butyl acrylate are used as monomers, styrene-n-butyl acrylate formed at this monomer ratio is used. Since the T g of the copolymer is 20 ° C., this monomer mixture is said to form a polymer having a T g of 20 ° C.

In addition, the provision that “at least one kind of a monomer for a core component that forms a polymer having a glass transition temperature of 80 ° C. or lower” does not necessarily mean that all of the monomers for a core component have a Tg of 8 or less. It does not mean that it must form a polymer at 0 ° C or lower. When one type of monomer is used as the monomer for the core component, the Tg of the homopolymer formed from the monomer must be 80 ° C or lower. However, when a mixture of two or more monomers is used as the monomer for the core component, it is sufficient that the Tg of the copolymer formed from the monomer mixture be 80 ° C or less. In addition, the monomer mixture may contain a single polymer having a Tg of more than 80 ° C. For example, the styrene homopolymer has a Tg of 100 ° C, but it may be used in admixture with a monomer that forms a low Tg polymer (eg, n-butyl acrylate). When Therefore, if a copolymer having a Tg of 80 ° C or less can be formed, styrene can be used as a kind of monomer for the core component. . Conversely, even a monomer that forms a polymer with a low T g can form a high T g copolymer by combining it with a monomer that forms a high T g. When it can be used, it can be used as a kind of monomer for sealing component.

The magnitude of the Tg between the core component polymer and the shell component polymer is relative. For example, when the monomer for the core component forms a polymer having a Tg of 80 ° C, the monomer for the shell component is a polymer having a Tg of more than 80 ° C. Must form However, when the monomer for the core component forms a polymer having a T g of 20 ° C., the monomer for the core component is, for example, a polymer having a T g of 60 ° C. It may form a body. Here, T g is a value measured by a normal measuring device such as DSC.

In the first polymerization step (first step) for forming the core component, at least one kind of monomer that forms a polymer having a Tg of 80 ° C. or less is used as a monomer. To adjust the T g, a monomer that gives a low T g polymer may be used alone, but usually a monomer that gives a high T _g polymer and a monomer that gives a low T _g polymer Use a combination of monomers. By using a plurality of monomers in combination, the desired Tg can be easily adjusted. The Tg of the polymer forming the core component is usually from 0 to 80 ° C, preferably from 10 to 60 ° C, more preferably from 15 to 50 ° C.

In the present invention, the monomer forming the core component needs to be selected so that the Tg of the polymer formed from the monomer is 80 ° C. or lower. To fix the toner image on a transfer material such as paper, In this heat-fixing step, the polymer of the core component is melted as a binder resin at a relatively low fixing temperature and penetrates into the transfer material. It is necessary to set T g to 80 ° C or less. In addition, in order for the fixed image to satisfy 0 HP transmission, it is necessary that the toner is uniformly melted on the OHP sheet. It is preferable to adjust the Tg of the solution to 80 ° C or less.

The monomer for the core component contains a coloring agent. In addition to the coloring agent, it is usually preferable to contain a radical polymerization initiator and various additives. These components are stirred and mixed by a mixer having a high shear force to prepare a core component monomer composition (core component monomer liquid) that is uniformly dispersed. The monomer composition for the core component is charged into an aqueous dispersion medium containing a dispersant, dispersed using a mixing device having a high shearing force, and granulated into fine droplets. Next, the suspension polymerization is usually performed at a temperature of 30 to 200 ° C. to make the polymerization conversion rate 80% or more. In this way, polymer particles serving as a core component are formed. If the polymerization conversion of the monomer forming the core component is less than 80%, a relatively large amount of the monomer for the core component will remain in the reaction system, and thus the monomer for the shell component or the monomer will not be used. It is difficult to form a high Tg shell component (coating layer) by copolymerization of both monomers even if the polymerization is continued after adding the monomer composition for shell component containing As a result, the effect of the encapsulation becomes insufficient. The polymerization conversion rate in the first polymerization step is preferably 85% or more, more preferably 90% or more.

In the first-stage polymerization step, various dispersion stabilizers used in ordinary suspension polymerization can be used as a dispersant. Examples of the polymerization initiator include, for example, 2,2-azoisoptyronitrile. For example, oil-soluble radical polymerization initiators used in ordinary suspension polymerization can be preferably used.

In the subsequent polymerization step (second step) for forming the shell component, the monomer for the shell component or the monomer is converted after the polymerization conversion of the monomer for the core component becomes 80% or more. The contained monomer composition for shell component (hereinafter sometimes referred to as monomer solution for shell component) is added to the reaction system, and the polymerization reaction is continued. As the monomer for the shell component, a monomer that forms a polymer having a higher Tg than the polymer of the core component is used. The monomer for the seal component can contain various additives such as a charge control agent, if necessary, and can be used as a monomer composition.

Monomers that form polymers having a high Tg, such as styrene and methyl methacrylate, can be used alone to form polymers having a Tg exceeding 80 ° C. It is preferable to use a combination of two or more. However, when the Tg of the polymer of the core component is much lower than 80 ° C, the monomer for the shell component may be a polymer that forms a polymer at 80 ° C or lower. . However, as the monomer that forms the shell component, the main purpose of encapsulation with the shell component polymer is to maintain the toner preservation. It is necessary to set g so as to be at least higher than the T g of the polymer of the core component. The Tg of the polymer forming the shell component is typically greater than 50 ° C and less than or equal to 120 ° C, preferably greater than 60 ° C and less than or equal to 110 ° C, and more preferably Exceeding 80 ° C and below 105 ° C. If the Tg of the seal component polymer is too low, even if the Tg is higher than the Tg of the core component polymer, the storage stability of the toner decreases, which is not preferable. The difference in Tg between the core and shell component polymers is typically at least 20 ° C, preferably at least 40 ° C, and more preferably at least 50 ° C. is there. When the monomer for the shell component or the monomer composition for the shell component containing the monomer is added to the reaction system, the particle size of the droplets is determined by the size of the polymer particles forming the core component. It is preferable that the number average particle diameter is smaller than the particle diameter. If the number average particle diameter of the droplets of the monomer for the monomer component or the monomer composition is larger than the particle diameter of the polymer particle of the core component, the core component toward the polymer particle side of the core component The transfer of the monomer for use is only due to the collision of the core component with the polymer particles, which is not efficient. When the number average particle diameter of the monomer or monomer composition droplets for the shell component is smaller than the particle diameter of the polymer particles of the core component, the polymer of the core component of the monomer for the shell component In addition to collisions with particles, thermodynamic transfer through a continuous medium also occurs, which is efficient. In order to add the monomer or monomer composition for the shell component as small droplets to the polymerization reaction system, a mixture of the monomer or the monomer composition and the aqueous dispersion medium is used, for example. It is preferable to perform a fine dispersion treatment using an ultrasonic emulsifier or the like and to add the monomer or the monomer composition as an aqueous suspension of liquid droplets.

If the solubility of the monomer for the shell component in the dispersion medium is less than 0.1% by weight, the monomer or the monomer composition for the shell component is added to the reaction system. Thus, the diameter of the droplet is several tens of meters or more, and is generally larger than the particle diameter of the polymer particles of the core component. In this case, as described above, the transfer of the monomer for the shell component to the polymer particle side of the core component is caused only by the collision of the core component with the polymer particles, which is not efficient. Moreover, it is difficult to uniformly introduce the shell component monomer into the core component polymer particles. Therefore, when using a monomer having extremely low solubility in water, such as styrene, a fine dispersion treatment is performed using an ultrasonic emulsifier or the like, and the liquid of the monomer or the monomer composition is used. It is preferable to add as a drop of water suspension. When the solubility of the monomer for the shell component in the dispersion medium is 0.1% by weight or more, droplets of the monomer or the monomer composition for the shell component, the core component, the polymer particles, and the aqueous system Since an equilibrium relationship was established between the dispersing media, it was found that the monomer for the shell component was rapidly transferred to the thermodynamically stable core component polymer particles. That is, the monomer for the sealing component is efficiently and uniformly introduced into the core component polymer particles. Therefore, if the monomer for the shell component has a solubility of 0.1% by weight or more (measured at 20 ° C) in water of the dispersion medium, it is not necessary to use an ultrasonic emulsifier. There is no need to perform the fine dispersion treatment, and the monomer can be added to the reaction system as it is. In this case, the monomer or monomer composition for the shell component may be added to the reaction system at a time if the reaction conversion of the core component polymer particles is 80% or more, or may be added to the plunger. It is possible to add continuously or intermittently using pumps such as pumps. Monomers having a solubility in water at 20 ° C of 0.1% by weight or more and suitable for forming a shell component polymer include, for example, methyl methacrylate, There are acrylonitrile, vinyl acetate, acrolein, etc., each of which may be used alone or in combination of two or more to form a polymer having a Tg of 50 °. It is desirable to use it in excess of C, preferably more than 60 ° C, and more preferably more than 80 ° C.

As a result of further research, the present inventors have found that in the second step of the present invention, an organic solvent having a solubility in water at 20 ° C of 5% by weight or more is added to the aqueous dispersion medium. Even when a monomer having a solubility in water at 20 ° C. of less than 0.1% by weight is used, a droplet of a monomer for a shell component or a monomer composition, a core component polymer, An equilibrium relationship is established between the particles and the dispersion medium, and the monomer for the silica component is thermodynamically stable. It was found that the particles rapidly migrated to the core component polymer particles. That is, the monomer for the shell component is efficiently and uniformly introduced into the polymer particles for the core component. The reason for this is that by adding an organic solvent in the second step, even if the monomer is extremely poorly soluble in water, the solubility in a dispersion medium is improved, and 0.1% by weight is obtained. This is presumed to be due to the above solubility. Therefore, when the organic solvent is added in the second step, when the monomer for the shell component or the monomer composition is added to the reaction system, fine dispersion treatment using an ultrasonic emulsifier or the like is always performed in advance. There is no need to keep it, and it can be added to the reaction system as it is. In this case, the monomer or monomer composition for the shell component may be added to the reaction system at a time if the polymerization conversion of the monomer for the core component is 80% or more, or Alternatively, it can be added continuously or intermittently using pumps such as a blender pump.

Monomers having a solubility in water at 20 ° C of less than 0.1% by weight and suitable for forming a cinyl component polymer include styrene and butylacrylate. And 2-ethylhexyl acrylate, ethylene, propylene and the like. Even when a monomer having a solubility in water at 20 ° C of 0.1% by weight or more is used, fine dispersion treatment using an ultrasonic emulsifier or the like may be performed, or an organic solvent may be added to the reaction system. By adding the compound, the shell component polymer can be formed more efficiently. Monomers having a solubility in water at 20 ° C of 0.1% by weight or more and suitable for forming the shell component polymer include, for example, methyl methacrylate , Acrylonitrile, vinyl acetate, and acryloline. These monomers may be used alone or in combination of two or more, and the Tg of the formed polymer is usually higher than 50 ° C, preferably higher than 60 ° C, and more preferably. Is 80 ° C It is desirable to use it in excess.

When an organic solvent is added to the reaction system in the second step, use an organic solvent having a solubility in water at 20 ° C of 5% by weight or more. With an organic solvent having a solubility in water of less than 5% by weight, it is difficult to increase the solubility of a poorly water-soluble monomer in a dispersion medium. Examples of such organic solvents include lower alcohols such as methanol, ethanol, isopropyl alcohol, n-propyl alcohol, butyl alcohol, etc .; Ketones such as methyl and methyl ethyl ketone; cyclic ethers such as tetrahydrofuran and dioxane: ethers such as dimethyl ether and getyl ether; dimethyl ether and the like Amides can be mentioned.

The amount of the organic solvent to be added is such that the solubility of the monomer for the shell component in the dispersion medium (aqueous organic solvent) becomes 0.1% by weight or more. The required amount of the organic solvent varies depending on the type and amount of the monomer for the shell component used, the type of the organic solvent, and the like. On the other hand, if a large amount of organic solvent is added to the aqueous dispersion medium, the suspension polymerization reaction may be inhibited. Therefore, the amount of the organic solvent to be added is usually 0.1 :! to 50 parts by weight, preferably 0.1 to 40 parts by weight, more preferably 0: 100 parts by weight, based on 100 parts by weight of the aqueous dispersion medium. It is desirable to use 1 to 30 parts by weight. The organic solvent can be added in the second step before, simultaneously with, or after the addition of the monomer for monomer or the monomer composition. Prior to the addition of the composition, it is desirable to add it to the aqueous dispersion medium from the viewpoint of efficiency. In particular, when a monomer or a monomer composition for a shell component containing a monomer having a solubility in water at 20 ° C of less than 0.1% by weight is used, an organic solvent is added to the reaction system. After the addition, the monomer or monomer composition for the shell component is added. It is preferable to continue the polymerization reaction by addition.

However, before adding an organic solvent to the reaction system, a monomer or monomer composition for a shell component containing a monomer having a solubility in water at 20 ° C of 0.1% by weight or more is added. And the organic solvent is added to the reaction system. Then, the monomer or monomer for shell component having a solubility in water at 20 ° C of less than 0.1% by weight is added. The polymerization reaction can be continued by adding the monomer composition. That is, in this method, in the second step, (i) the first shell having a solubility in water at 20 ° C of 0.1% by weight or more before adding an organic solvent to the reaction system. The monomer for the component or the monomer composition for the first shell component containing the monomer is added to carry out a polymerization reaction. Then, (ii) an organic solvent and 20 ° C. are added to the reaction system. Polymerization is carried out by adding a monomer for the second shell component or a monomer composition for the second shell component containing the monomer having a solubility of C in water of less than 0.1% by weight. Do. According to this method, a seal having a two-layer structure can be formed, whereby the fixing temperature of the toner can be adjusted. The ratio of the first shell component to the second shell component can be determined as appropriate, but is usually 1: 9 to 9: 1 by weight.

In the second step, when the monomer for the shell component or the monomer composition is added to the polymerization reaction system, a water-soluble radical initiator may be added simultaneously with or after the addition. I like it. By adding the water-soluble radical initiator, the radicals generated in the aqueous medium enter the polymer particles by collision, and the monomer for the cinyl component is located near the surface of the polymer particles. During the period of time (ie, before the monomer for the shell component is completely absorbed into the polymer particles), the polymerization reaction can be started to easily form a capsule wall (shell). .

Water-soluble radical initiators include sodium persulfate and ammonium persulfate. Persulfates such as dimethyl; 4,4-azobis (4—cyanovaleric acid), 2,2-azobis (2—amidinopropane) dihydrochloride, 2,2—azobis 2—me Cyl-N-1,1,1-bis (hydroxymethyl) 1-2-azo initiators, such as hydroxysethylpropioamide; oil-soluble initiators, such as cumeneperoxide, and redox catalysts Combinations; and the like. The amount used is 0.001-1% by weight based on the aqueous medium. If the amount is less than 0.001% by weight, a sufficient effect cannot be exerted. If the amount is more than 1% by weight, particles having a particle diameter of less than 1 / zm are undesirably produced as by-products.

In this way, capsule-type colored polymer particles (toner particles) consisting of 40 to 99% by weight of the core component and 1 to 60% by weight of the sealing component are produced.

Simple body

In the present invention, the monomer forming the core component needs to be selected so that the Tg of the polymer formed from the monomer is 80 ° C. or lower. On the other hand, the monomer forming the shell component is set so that the Tg of the polymer formed from the monomer is at least higher than the Tg of the polymer of the core component. There is a need to.

In the present invention, a vinyl monomer is usually used as the polymerizable monomer for the core component and the shell component. By using these vinyl monomers alone or in combination of two or more, the Tg of the polymer of the core component and the sil component is adjusted to a desired range. Examples of the vinyl monomer used in the present invention include styrene monomers such as styrene, vinyltoluene, and α-methylstyrene; acrylic acid and methacrylic acid. ; (Meth) methyl acrylate, (meth) ethyl acrylate, (meth) propyl acrylate, (meth) acrylic acid Acrylic acid such as butyl, (meth) acrylinoleic acid 2-ethylhexyl, dimethylaminoethyl (meth) acrylate, acrylonitrile, acrylamide, etc. Derivatives of phosphoric acid or methacrylic acid; ethylenically unsaturated monoolefins such as ethylene, propylene, and butylene; vinyl chloride, vinylidene chloride, vinyl fluoride, etc. Vinyl esters such as vinyl acetate and vinyl propionate; vinyl ethers such as vinyl methyl ether and vinyl ethyl ether; vinyl ketones such as vinyl methyl ketone and methyl isopropenyl ketone; Nitrogen-containing vinyl compounds such as 2-vinylpyridin, 4-vinylpyridin, and N-vinylpyrrolidone; and the like. These vinyl monomers may be used alone, or a plurality of monomers may be used in combination.

As a monomer having a solubility in water at 20 ° C of 0.1% by weight or more, for example, (meth) acrylic acid esters such as (meth) methyl acrylate; Amides such as (meth) acrylamide; (meth) vinyl cyanide compounds such as acrylonitrile; 4-nitrogen-containing vinyl compounds such as vinylpyridin; Examples include vinyl acetate and acrolein. On the other hand, monomers having a solubility in water at 20 ° C of less than 0.1% by weight include, for example, styrene, butyl acrylate, 2-ethylhexyl acrylate, and ethylene. And propylene.

Any cross-linking agent can be used as required with these vinyl monomers. Examples of the cross-linking agent include aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene, and derivatives thereof; ethylene glycol dimethacrylate, diethyl alcohol, and the like. Diethylenically unsaturated sulfonic acid esters such as dimethacrylate; N, N—divinyl compounds such as divinylaniline and divinyl ether; 3 Compounds having at least two vinyl groups; and the like. These crosslinking agents can be used alone or in combination of two or more. In the present invention, the crosslinking agent may be used in a proportion of usually 0.1 to 5 parts by weight, preferably 0.3 to 2 parts by weight, based on 100 parts by weight of the vinyl monomer. Desirable.

Dispersant

In the present invention, as a dispersant (dispersion stabilizer) used in suspension polymerization, those used in ordinary suspension polymerization can be used. Dispersants are generally classified into two types: water-soluble polymers that form a protective colloid film and exhibit repulsion due to steric hindrance, and poorly water-soluble inorganic substances. Examples of the water-soluble polymer include polyvinyl alcohol, methyl cellulose, gelatin, and the like. Examples of the poorly water-soluble inorganic substance include poorly water-soluble salts such as calcium phosphate, barium sulfate, calcium sulfate, barium carbonate, calcium carbonate, and magnesium carbonate; talc, Inorganic polymer substances such as silicic acid; metal oxides such as aluminum oxide and titanium oxide; metal hydroxides such as aluminum hydroxide and ferric hydroxide; and the like. .

As the dispersant, it is preferable to use a poorly water-soluble metal hydroxide colloid formed by the reaction of a water-soluble polyvalent metal salt and an alkali metal hydroxide in an aqueous phase. Hardly water-soluble metal hydroxide Shioko Roy de this, it the number particle size distribution, D _5. (50% cumulative value of number particle diameter distribution) 0. Below, D _9. (90% cumulative value of the number particle size distribution) is preferably 1 βm or less.

The dispersant is generally used in an amount of 0.1 to 20 parts by weight based on 100 parts by weight of the vinyl monomer. If the proportion is less than 0.1 part by weight, it is difficult to obtain sufficient polymerization stability, and polymerized aggregates are formed. It is easier to achieve. Conversely, if the amount exceeds 20 parts by weight, the effect of polymerization stability is saturated, and it is not economical.

Oil-soluble polymerization initiator

The oil-soluble polymerization initiator used in the first polymerization step may be any one which is soluble in the monomer used. For example, methylethylperoxide, tert-butylperoxide Acetylperoxide, dimethylaminoperoxide, lauroy leperoxide, benzoyl oleperoxide, t-butylperoxy 1-2-ethylethyl hexanoate, gisopropylperoxy dicarbonate, di-t-butylperoxy Peroxides such as isophthalate, succinic amidoperoxide, t-butyl-peroxy-isobutyrate, t-hexyl-perenoxy-2—ethynolehexanoate; 2, 2 '-azobis (2, 4-dimethyl thyroneronitrile), 2, 2'-azobisisobutyronitrile, 1, 1 ' § zone compounds such as bis (-1-Shi hexa Nkarubo two preparative Li Le to click b); Ru can and this and the like.

Among these oil-soluble initiators, the temperature at which the half-life is 10 hours is obtained because the obtained toner has a low odor during the printing evaluation and a low environmental destruction due to volatile components such as odor. Organic peroxide having a (10 hour half-life) of 60 to 80 ° C, preferably 65 to 80 ° C, and a molecular weight of 250 or less, especially t-butylperoxy- 1 2 —Ethylhexanoe is preferred. If the 10-hour half-life of the oil-soluble polymerization initiator is less than 60 ° C, the polymerization temperature will be 80 ° C or less, and the amount of residual monomer will increase. If the 10-hour half-life exceeds 80 ° C, the polymerization temperature will rise to 100 ° C or more, and it will be necessary to withstand pressure in the polymerization vessel. If the molecular weight of the oil-soluble polymerization initiator exceeds 250, the molecular weight of the decomposition product of the polymerization initiator increases after the reaction, and does not fly during drying, the amount of volatile components increases, and the odor increases. Becomes stronger. In general, azo-based polymerization initiators tend to have a strong odor. Even if the molecular weight of the polymerization initiator is 250 or less, the amount of the residual monomer tends to increase for those having an aromatic ring. The reason is presumed to be that the presence of a coloring agent such as black pigment inhibits the polymerization reaction.

These oil-soluble polymerization initiators are usually used in an amount of 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the polymerizable monomer. Used.

Colorant

Examples of the coloring agent used in the present invention include carbon black, nig mouth sieve, aniline blue, canoleco oil blue, chrome yellow, unoleta laminate, o Dyes and pigments such as lent oil, red phthalocyanine, malachite green oxalate, etc .; cobalt, nigel, iron sesquioxide, iron tetroxide, iron oxide manganese, zinc oxide, zinc oxide Magnetic particles such as iron nickel; and the like. The dyes and pigments are generally used in an amount of 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the polymerizable monomer. The magnetic particles are generally used in an amount of 1 to 100 parts by weight, preferably 5 to 50 parts by weight, based on 100 parts by weight of the polymerizable monomer.

Additive

To the polymerizable monomer composition (monomer liquid), various additives such as an oil-soluble polymerization initiator, a molecular weight modifier, a crosslinking agent, a release agent, and a charge control agent may be added as necessary. It can be. The oil-soluble polymerization initiator and the crosslinking agent are as described above.

Examples of the molecular weight regulator include t-dodecylmercaptan, n-dodecylmercaptan, and n-methyldecanolcaptan. Tans; halogenated hydrocarbons such as carbon tetrachloride and carbon tetrabromide; and the like. These molecular weight regulators can be added before the start of the polymerization or during the polymerization. The molecular weight modifier is used in an amount of usually from 0.01 to 10 parts by weight, preferably from 0.1 to 5 parts by weight, based on 100 parts by weight of the polymerizable monomer.

Examples of the release agent include low-molecular-weight polyolefins, such as low-molecular-weight polypropylene, low-molecular-weight polypropylene, and low-molecular-weight polybutylene; and paraffin wax. , Etc .; The release agent is used in an amount of usually 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the polymerizable monomer.

The charge control agent is preferably contained in the polymerizable monomer composition in order to improve the chargeability of the toner. As the charge control agent, various types of positively or negatively chargeable charge control agents can be used. Specific examples of the charge control agent include Niguchi Shin NO 1 (Oriental Chemical), Nigguchi Shin EX (Orient Chemical), Spiro Black TRH (Hodogaya Chemical) ), T-77 (Hodogaya Chemical), Bontron S-34 (Orient Chemical), Bontron E-84 (Oriental Chemical) Manufactured). The charge controlling agent is used in an amount of usually from 0.01 to 10 parts by weight, preferably from 0.1 to 5 parts by weight, based on 100 parts by weight of the polymerizable monomer. It is preferable to use a charge control agent together with the monomer for the shell component, because the resulting toner has less capri.

In addition, lubricants such as oleic acid and stearic acid; silane-based or titanium-based coupling agents are used to uniformly disperse the colorant in the toner particles. And the like may be contained in the polymerizable monomer composition. Such lubricants and dispersants are based on the weight of the colorant, Usually, it is used at a rate of about 110 to 150.

Toner for developing electrostatic image

The toner for developing an electrostatic image of the present invention comprises 40 to 99% by weight, preferably 50 to 95% by weight, and 1 to 60% by weight, preferably 5 to 50% by weight of the core component. To 50% by weight of capsule type toner particles. If the ratio of the shell component is too small, the effect of improving the storage stability by encapsulation is small. Conversely, if the ratio is too large, the effect of reducing the fixing temperature and improving the OHP permeability is reduced.

The toner for developing an electrostatic image of the present invention usually has a volume average particle diameter of 2 to 20 m, preferably 3 to 15 / m, and a particle size distribution (volume average particle diameter and number average particle diameter). The particle size distribution is less than 1.6, preferably less than 1.5, and is a sharp spherical fine particle. When the toner for developing an electrostatic image obtained by the production method of the present invention is used, the fixing temperature is lowered to 80 to 180 ° C., preferably 100 to 150 ° C. It can be reduced, does not aggregate during storage, and has excellent storage properties.

Image forming device

The electrostatic image developing toner of the present invention is used in an image forming apparatus utilizing electrophotography.

FIG. 1 shows a cross-sectional view of an example of the image forming apparatus. In this image forming apparatus, a photosensitive drum 1 as an image carrier is rotatably mounted in the direction of an arrow. The photoreceptor drum 1 generally has a structure in which a photoconductive layer is provided on the outer periphery of a conductive support drum body. The photoconductive layer is composed of, for example, an organic photoconductor, a selenium photoconductor, a zinc oxide photoconductor, an amorphous silicon photoconductor, or the like.

Around the photoreceptor drum 1, along the circumferential direction, a charging unit 3, a latent image forming unit 4, a developing unit 5, a transfer unit 6, and a cleaning unit 2 are located. The charging means 3 has a function of uniformly charging the surface of the photoreceptor drum 1 in a positive or negative manner.In addition to the charging port shown in FIG. 1, for example, a corona discharge device, a charging blade, or the like is used. be able to. The latent image forming means 4 irradiates light corresponding to an image signal onto a uniformly charged surface of the photoreceptor drum with a predetermined pattern to form an electrostatic latent image on an irradiated portion (reversal development ) Or forms an electrostatic latent image in the area where light is not irradiated (regular development method). The latent image forming means 4 is composed of, for example, a combination of a laser device and an optical system, or a combination of an LED array and an optical system. The developing means 5 has a function of attaching a developer (toner) to the electrostatic latent image formed on the surface of the photoconductor drum 1. The developing means 5 is usually composed of a developing roller 8, a blade 9 for a developing port roller, a housing means (housing case) 11 for the developer 10 and a developer supplying means (one supply port) 1 2 It is a developing device provided with. The developing roller 8 is disposed to face the photoconductor drum 1, and is usually disposed close to the photoconductor drum 1 so that a part thereof is in contact with the photoconductor drum 1. Rotate in the opposite direction. The supply roller 12 contacts the developing roller 8 so as to rotate in the same direction as the developing roller 8, and supplies the toner 10 to the outer periphery of the developing roller 8. When the developing roller 8 is rotated in the developing device, the toner 10 in the developer accommodating means 11 adheres to the outer peripheral surface due to electrostatic force or the like due to friction. The developing port roller blade 9 is in contact with the outer peripheral surface of the rotating developing roller 8 to adjust the thickness of the toner layer formed on the outer peripheral surface of the developing roller 8. In the case of the reversal developing method, the toner is adhered only to the light-irradiated portion of the photosensitive drum 1, and in the case of the regular developing method, the toner is attached to the developing roller 8 so that the toner is adhered only to the light-irradiated portion. Bias voltage is applied between photoconductor drum 1 and photoconductor drum 1. The transfer means 6 is for transferring the toner image formed on the surface of the photosensitive drum 1 by the developing means 5 to a transfer material (transfer paper) 7. In addition to the transfer roller shown in FIG. For example, a corona discharge device, a transfer belt, or the like can be used. The cleaning means 2 is for cleaning the toner remaining on the surface of the photoreceptor drum 1, and is composed of, for example, a cleaning blade. This cleaning means is not always necessary in the case of a method in which the cleaning action is performed simultaneously with the development.

Therefore, according to the present invention, a storage unit that stores the toner for developing an electrostatically charged image obtained by the manufacturing method, a supply unit that supplies the toner stored in the storage unit, an image carrier, and an image carrier Developing means for developing the electrostatic latent image formed on the image carrier using the toner supplied by the supply means, and developing the toner image on the transfer material An image forming apparatus having a transfer unit for transferring is provided.

Example

Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples. However, the present invention is not limited to only these Examples. Parts and percentages are by weight unless otherwise specified.

The methods for measuring physical properties in Examples and Comparative Examples are as follows.

(1) Grain size

The particle diameter of the toner particles is determined by a Coulter Counter (manufactured by Coulter Co., Ltd.) according to the volume average particle diameter (dv) and the particle size distribution, ie, the ratio (dv) between the volume average particle diameter and the number average particle diameter (dp). / dp). In the measurement using this call counter, the following parameters were used. Was used.

①Aperture diameter: l O O m

② Medium: Isoton Π

③ Concentration: 15%

個数 Number of particles measured: 500 0 0

(2) Toner volume resistivity

The volume resistivity of the toner was measured using a dielectric loss measuring instrument (trade name: TRS-10, manufactured by Ando Electric Co., Ltd.) at a temperature of 30 and a frequency of 1 kHz.

(3) Toner fixing temperature

Toner image evaluation was performed on a printer that was modified so that the temperature of the fixing roll of a commercially available non-magnetic one-component developing printer could be changed. The temperature at which the fixing rate was 80% was evaluated as the fixing temperature. The fixing test was carried out by changing the temperature of the fixing roll of the printer, measuring the fixing rate at each temperature, and determining the relationship between the constant temperature fixing rates. The fixation rate was calculated from the ratio of the image density before and after the tape peeling operation in the solid black area on the test paper printed with the modified printer. That is, assuming that the image density before tape removal is before ID and the image density after tape removal is after ID,

Fixing rate (%) = (after ID and before ID) X 100

It is. Here, the solid black area is an area that is controlled so that toner is attached to all of the dots (virtual that controls the printer's regular working area) inside the area. The tape peeling operation is to apply an adhesive tape (Sumitomo Slim Co., Ltd.'s Scottish Mending Tape 8.10-3-18) to the measurement part for the test paper, and press it with a constant pressure to adhere. After that, a series of operations to peel off the adhesive tape in the direction along the paper at a constant speed It is. The image density was measured using a reflection image densitometer manufactured by McBeth.

(4) Toner preservation

To evaluate the shelf life, place the toner sample in a closed container, seal it, submerge it in a temperature-controlled water bath, remove it after a certain period of time, and weigh the aggregated toner. It was measured. The sample removed from the container was transferred onto a 42-mesh sieve so as not to destroy the structure as much as possible, and the vibration intensity was measured using RE 0 STAT of a powder measuring machine (manufactured by Hosokawa Miclon). After setting to 4.5 and vibrating for 30 seconds, the weight of the toner remaining on the sieve was measured to be the weight of the aggregated toner. The toner aggregation rate (% by weight) was calculated from the weight of the aggregated toner and the weight of the sample. The storage stability of the toner was evaluated on the following four scales.

◎: aggregation rate is less than 5% by weight,

〇: The aggregation rate is 5% by weight or more and less than 10% by weight,

Δ: The aggregation rate is 10% by weight or more and less than 50% by weight,

: Aggregation rate is 50% by weight or more.

(5) 0 HP permeability

The temperature of the fixing roll of the modified printer was set at 180 ° C, and printing was performed using a commercially available 0 HP (Transmitter Lance made by Uchida Yoko Co., Ltd.) sheet, and the toner was removed. 0 HP permeability was evaluated. It was visually observed whether or not the print penetrated the 0 HP sheet, and the transmission or non-transmission was evaluated.

[Example 1]

60 parts of polystyrene, 40 parts of n-butyl acrylate, 5 parts of carbon black (manufactured by Degussa, trade name: PINTEX 150 T), 5 parts of antistatic agent (manufactured by Hodogaya Chemical Co., Ltd.) , Trade name Spiral Black TRH) 1 copy, 0.3 parts of divinylbenzene, and 2 parts of 2,2-azobisisoptyronitrile (calculated copolymer for core component T g = 20 ° C) Using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), the mixture was stirred and mixed at a rotation speed of 600 rpm to prepare a uniformly dispersed core component monomer composition.

On the other hand, in an aqueous solution in which 9.8 parts of magnesium chloride (water-soluble polyvalent metal salt) is dissolved in 250 parts of ion-exchanged water, sodium hydroxide (alkaline hydroxide) is added to 50 parts of ion-exchanged water. An aqueous solution in which 6.9 parts were dissolved was gradually added under stirring to prepare a dispersion of magnesium hydroxide colloid (a poorly water-soluble metal hydroxide colloid). The particle size distribution of the generated colloid was measured with a microtrack particle size distribution analyzer (manufactured by Nikkiso Co., Ltd.). The particle size was D50 ( ₅₀ % cumulative value of the number particle size distribution). Was 0.38 m, and D90 ( ₉₀ % cumulative value of the number particle size distribution) was 0.82 m. The following parameters were used in the measurement using the microtrack particle size distribution analyzer.

Measuring range: 0.12 to 704 ^ m

Measurement time: 30 seconds

Medium: ion exchange water

On the other hand, 10 parts of styrene (calculated T g = 100 ° C) and 100 parts of water were finely dispersed by an ultrasonic emulsifier (manufactured by Ultrasonic Industries) to obtain shell components. A dispersion of the monomer was prepared. The particle size of the finely dispersed monomer droplets in the ultrasonic emulsifier was determined by adding the resulting droplets to a 1% aqueous sodium hydroxide solution at a concentration of 3%. this filtrate and was measured using the clock particle size distribution measuring instrument, D ₉₀ was Tsu 1.6 〃 m der.

The above polymerizable monomer composition for a core component is added to the magnesium hydroxide colloid dispersion obtained above, and a TK homomixer is used. Then, the mixture was subjected to high shear stirring at a rotation speed of 800 rpm to form droplets (monomer composition particles) of the core component monomer composition. The aqueous dispersion of the granulated core component monomer composition was put into a reactor equipped with a stirring blade, and the polymerization reaction was started at 65 ° C. When the polymerization conversion reached 80%, Then, a dispersion of the monomer for the shell component was added to the reactor, and then 1 part of a 1% aqueous solution of persulfuric acid in water was added as a water-soluble radical initiator, followed by a reaction for 5 hours. The reaction was completed to obtain an aqueous dispersion of polymer particles (toner particles). The number average particle diameter (dp) of the colored polymer particles of the core component having a polymerization conversion rate of 80% measured by the Coulter counter method was 5.7 / m.

When the particle size of the toner particles after the completion of the polymerization reaction was measured by a Coulter counter (manufactured by Coulter, Inc.), the volume average particle size (dv) was 5.8 / m, and the particle size distribution, that is, the volume The ratio (dv / dp) between the average particle size and the number average particle size (dp) was 1.32. After embedding the obtained toner particles in epoxy resin, it was cut to a thickness of 1 mm with an ultramicrometer, and the cut surface was observed with a transmission electron microscope. It was confirmed that a seal having a thickness of 0.2 m was generated.

While stirring the aqueous dispersion of the polymer particles obtained as described above, the pH of the system was adjusted to 4 or less with sulfuric acid, followed by acid washing (25 ° C for 10 minutes), followed by filtration. After the water was separated, 500 parts of ion-exchanged water was added to re-slurry, and the water was washed. After that, dehydration and washing with water were repeated several times again, and the solid content was separated by filtration, followed by drying at 50 ° C. for 24 hours in a drier to obtain toner particles.

To 100 parts of the toner particles obtained as described above, 0.3 part of hydrophobically treated colloid darcilica (trade name: R-972, manufactured by Nippon Aerosil Co., Ltd.) was added.混合 Mix using a mixer to prepare the toner. Was. When the volume resistivity of the toner thus obtained was measured, it was 1.0 × ^{10 11} Ω · cm.

When the fixing temperature was measured using the toner obtained as described above, it was 130 ° C. Further, the preservability of this toner was very good (evaluation = ◎). Table 1 shows the results. In other image evaluations, an image having a high image density, no capri and unevenness, and an extremely good resolution was obtained.

[Example 2]

In Example 1, the dispersion of the monomer for the Schul component and the 1% aqueous solution of potassium persulfate added during the polymerization were mixed at the time of the polymerization conversion of the monomer composition for the core component of 93%. A polymerized toner was obtained in the same manner as in Example 1 except that the toner was added. Table 1 shows the measurement results of the particle size, the fixing temperature, and the storage stability of the obtained toner particles.

[Example 3]

In Example 1, except that the amount of styrene as the monomer for the shell component added during the polymerization was changed to 20 parts, and the amount of the 1% persulfuric acid aqueous solution was changed to 2 parts. A polymerized toner was obtained in the same manner as in Example 1. Table 1 shows the measurement results of the particle size, fixing temperature, and storage stability of the obtained toner particles.

[Comparative Example 1]

A polymerized toner was prepared in the same manner as in Example 1 except that the dispersion of the monomer for the shell component and the 1% aqueous persulfuric acid solution were not added during the polymerization. I got Table 1 shows the measurement results of the particle diameter, fixing temperature, and storage stability of the obtained toner particles.

[Comparative Example 2]

In Example 1, the polymerization conversion of the core component monomer reached 80%. Instead of the dispersion of the monomer for the shell component and the aqueous solution of persulfuric acid realm to be added in this case, 10 parts of styrene, 2,2,2-azobisisobutyronitrile 0.2 Parts, and a mixture of 100 parts of water was added to obtain a polymerized toner in the same manner as in Example 1. Table 1 shows the measurement results of the particle size, fixing temperature, and storage stability of the obtained toner particles.

[Example 4]

In Example 1, potassium persulfate as a water-soluble radical initiator added during the polymerization was added to 2,2-azobis-1-methyl-1-N-1,1-bis (hydroxymethyl) -1. 2—A polymerized toner was obtained in the same manner as in Example 1, except that hydroxysethyl propionamide was used instead. Table 1 shows the measurement results of the particle size, fixing temperature, and storage stability of the obtained toner particles.

[Example 5]

In Example 1, the amounts of styrene and n-butyl acrylate in the monomer composition for the core component were respectively adjusted to 75 parts of styrene and 25 parts of n-butyl acrylate ( A polymerized toner was obtained in the same manner as in Example 1 except that the calculation T g was changed to 44 ° C.). Table 1 shows the measurement results of the particle size, fixing temperature, and storage stability of the obtained toner particles.

[Example 6]

In Example 1, the amounts of styrene and n-butyl acrylate in the monomer composition for the core component were 55 parts by weight of styrene and 45 parts by weight of n-butyl acrylate (calculation T g = 10 ° C.), except that the polymerization method was changed to the same as in Example 1 to obtain a polymerized toner. Table 1 shows the measurement results of the particle size, fixing temperature, and storage stability of the obtained toner particles.

[Example 7]

In Example 1, the amount of the monomer for the shell component added during the polymerization was more than In performing the fine dispersion treatment using a sonic emulsifier, 0.001 part of sodium dodecylpentene sulfonate (manufactured by Wako Pure Chemical Industries, Ltd.) was added. At that time, D _{9 of} the monomer finely dispersed droplets. Was 0.95 m. Except for this, a polymerized toner was obtained in the same manner as in Example 1. Table 1 shows the measurement results of the particle size, fixing temperature, and storage stability of the obtained toner particles.

[Example 8]

In Example 1, 0.01 part of a charge controlling agent (Bontron E-84, manufactured by Orient Chemical Co.) was added to the monomer for the shell component added during the polymerization. Except for the above, a polymerization toner was obtained in the same manner as in Example 1. Table 1 shows the measurement results of the particle size, fixing temperature, and storage stability of the obtained toner particles.

[Example 9] (color toner)

In Example 1, instead of carbon black, phthalocyanine was used. Polymerized toner was obtained in the same manner as in Example 1 except that 5 parts of blue (GNX manufactured by Sumitomo Chemical Co., Ltd.) were used. Table 2 shows the measurement results of the toner particle size (dv), the fixing temperature, the storability, and the 0 HP permeability.

[Comparative Example 3]

A polymerized toner was obtained in the same manner as in Comparative Example 1 except that 5 parts of phthalocyanine blue (GNX, manufactured by Sumitomo Chemical Co., Ltd.) was used in place of Rikichi Bon Black in Comparative Example 1. Was. Table 2 shows the measurement results of the toner particle size (dv), the fixing temperature, the storability, and the OHP transmittance.

[Comparative Example 4]

In Comparative Example 1, 5 parts of phthalocyanine blue (GNX, manufactured by Sumitomo Chemical Co., Ltd.) was used instead of the carbon black, and the styrene and black in the monomer composition for the core component were used. A polymerized toner was obtained in the same manner as in Comparative Example 1, except that the amount of n-butyl acrylate was changed to 85 parts of styrene and 15 parts of n-butyl acrylate, respectively. . Table 2 shows the measurement results of the toner particle size (dV), the fixing temperature, the storability, and the OHP transmittance. Table 2

[Example 10]

Example 10 shows an experimental example in which, in Example 1, styrene as the monomer for the sil component was replaced with methyl methacrylate, and fine dispersion treatment was not performed using an ultrasonic emulsifier. .

60 parts of styrene, n-butyl acrylate 40 parts, carbon bra 5 parts (Degsa, Printex 150T), 1 part of antistatic agent (Hodogaya Chemical, Spiron Black TR II), 1 part of divinylbenzene 3 parts and 2 parts of 2,2 -azobisisoptyronitrile (calculation of the copolymer for the core component T g = 20 ° C) were added to a TK homomixer with a high shear mixer. The mixture was stirred and mixed with a mixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) at a rotation speed of 600 rpm to prepare a uniformly dispersed monomer composition for a core component.

On the other hand, in an aqueous solution obtained by dissolving 9.8 parts of magnesium chloride (a water-soluble polyvalent metal salt) in 250 parts of ion-exchanged water, and 50 parts of ion-exchanged water with sodium hydroxide (alkali hydroxide). An aqueous solution in which 6.9 parts of a metal salt were dissolved was gradually added with stirring to prepare a magnesium hydroxide colloid (poorly water-soluble metal hydroxide colloid) dispersion. The particle size distribution of the produced colloid was measured with a Microtrack Particle Size Distribution Analyzer (manufactured by Nikkiso Co., Ltd.). The particle size was D50 ( ₅₀ % cumulative value of the number particle size distribution). ) in to zero. 3 8 〃 m, D _9. (90% cumulative value of number particle size distribution) was 0.82 m ο

The polymerizable monomer composition for a core component is charged into the magnesium hydroxide colloid dispersion obtained as described above, and a high shear is performed at 800 rpm using a TK homomixer. By stirring, droplets (monomer composition particles) of the monomer composition for the core component were granulated. The aqueous dispersion of the granulated core component monomer composition was put into a reactor equipped with a stirring blade, and the polymerization reaction was started at 65 ° C. When the polymerization conversion reached 80%, Then, 10 parts of methyl methacrylate (calculated T g = 105 ° C) as a monomer for the shell component was added to the reactor, and then 1% as a water-soluble radical initiator. One part of an aqueous solution of potassium persulfate was added, and then the reaction was continued for 5 hours to complete the reaction. The aqueous dispersion of polymer particles (toner particles) was removed. Obtained.

When the particle size of the toner particles after the completion of the polymerization reaction was measured by a Coulter-Counter (manufactured by Coulter Co., Ltd.), the volume average particle size (dv) was 5.7 // m, and the particle size was 5.7 // m. The diameter distribution, that is, the ratio (dv / dp) between the volume average particle diameter and the number average particle diameter (dp) was 1.31. After embedding the obtained toner particles in an epoxy resin, it was cut into 1 mm thick with an ultramicrotome, and the cut surface was observed with a transmission electron microscope. It was confirmed that a shell having a thickness of 2 / zm was formed.

While stirring the aqueous dispersion of the polymer particles obtained as described above, the pH of the system was adjusted to 4 or less with sulfuric acid, followed by acid washing (25 ° C for 10 minutes), followed by filtration. After the water was separated, 500 parts of ion-exchanged water was newly added for re-slurrying and washing with water. After that, dehydration and washing with water were repeated several times again, and the solid content was separated by filtration, followed by drying at 50 ° C. for 24 hours in a drier to obtain toner particles.

To 100 parts of the toner particles obtained as described above, 0.3 part of hydrophobically treated colloidal silica (trade name: R—972, manufactured by Nippon Aerosil Co., Ltd.) was added, and Mixing was performed using a shell mixer to prepare a toner. When the volume resistivity of the toner thus obtained was measured, it was 1. SxlOHQ.cm.

When the fixing temperature was measured using the toner obtained above,

130 ° C. In addition, the storage stability of this toner was very good (evaluation = ◎). Table 3 shows the results. In other image evaluations, an image having a high image density, no capri and glares, and an extremely good resolution was obtained.

[Example 11]

In Example 10, methyl methacrylate added during the polymerization And a 1% aqueous solution of potassium persulfate was added at the time of the polymerization conversion of the monomer composition for the core component of 93% by the same operation method as in Example 10. A polymerized toner was obtained. Table 3 shows the measurement results of the particle size, the fixing temperature, and the storage stability of the obtained toner particles.

[Example 12]

In Example 10, the amount of methyl methacrylate added during the polymerization was changed to 20 parts, and the amount of 1% persulfuric acid aqueous solution was changed to 2 parts. Except for the above, a polymerization toner was obtained by the same operation method as in Example 10. Table 3 shows the measurement results of the particle size, fixing temperature, and storage stability of the obtained toner particles.

[Example 13]

In Example 10, except that the methyl methacrylate as the monomer for the seal component was changed to atalylonitrinole (calculated T g = 125 ° C), By the same operation method as in Example 10, a polymerized toner was obtained. Table 3 shows the measurement results of the particle diameter, fixing temperature, and storage stability of the obtained toner particles. Table 3

[Example 14]

Example 10 is the same as Example 10 except that carbon black was replaced by 5 parts of Phthalocyanine Nimble (GNX manufactured by Sumitomo Chemical Co., Ltd.). Polymerized toner was obtained in the same manner as in Example 10. As a result of evaluation of this polymerization toner, the toner particle size (dv) was 5.9 // m, the fixing temperature was 130 ° C., the storage stability was ◎, and the 0 HP transmission was transparent.

[Example 15]

60 parts of styrene, 40 parts of n-butyl acrylate, 5 parts of carbon black (manufactured by Degussa, trade name: PRINTEX 150 T), 5 parts, antistatic agent (manufactured by Hodogaya Chemical Co., Ltd.) 1 part of trade name, spiromb black TRH), 0.3 part of divinylbenzene, and 2 parts of 2,2—azobisisobutyronitrile (calculated copolymer for core component T g- 20 ° C) was uniformly mixed by stirring and mixing at a rotation speed of 600 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), which is a mixer having a high shearing force. A monomer composition for a core component was prepared.

On the other hand, 9.8 parts of magnesium chloride (water-soluble polyvalent salt) was dissolved in 250 parts of ion-exchanged water, and sodium hydroxide was added to 50 parts of ion-exchanged water. (Alkali metal hydroxide) 6. An aqueous solution in which 9 parts were dissolved was gradually added with stirring to prepare a dispersion of magnesium hydroxide colloid (a poorly water-soluble metal hydroxide metal colloid). . When a particle size distribution of the generated above colloids was measured with a microphone collected by filtration rack particle size distribution analyzer (manufactured by Nikkiso Co., Ltd.), the particle size, D _5. (50% cumulative value of number particle size distribution) is 0.38 m and D ₉ . (90% cumulative value of the number particle size distribution) was 0.82 m. The following parameters were used in the measurement with this microtrack particle size distribution analyzer.

Measurement range: 0.12 to 704 / m

Measurement time: 30 seconds

Medium: ion exchange water

The magnesium hydroxide colloid dispersion obtained above was added to the dispersion The polymerizable monomer composition for the core component is charged, and the mixture is subjected to high shear stirring at a rotation speed of 800 rpm using a TK type homomixer. Composition particles) were granulated. The aqueous dispersion of the granulated core component monomer composition was put into a reactor equipped with a stirring blade, and the polymerization reaction was started at 65 ° C. When the polymerization conversion reached 80%, And 20 parts of methanol were added. 10 minutes later, 10 parts of styrene (calculated T g = 100 ° C) was added to the reactor as a monomer for a sealing component, and then a 1% aqueous solution of potassium persulfate was added. Then, the reaction was continued for 5 hours to complete the reaction, and a water dispersion of polymer particles (toner particles) was obtained.

The particle size of the toner particles after the completion of the polymerization reaction was measured with a Coulter counter (manufactured by Coulter, Inc.), and the volume average particle size (dv) was 5. Diameter and number average particle size

The ratio (d vZ d p) to (d p) was 1.31. After embedding the obtained toner particles in an epoxy resin, it was cut to a thickness of 1 mm with an ultramicrotome, and the cut surface was observed with a transmission electron microscope. It was confirmed that a shell having a thickness of 2 / m was formed. While stirring the aqueous dispersion of the polymer particles obtained as described above, the pH of the system was adjusted to 4 or less with sulfuric acid, followed by acid washing (25 ° C for 10 minutes), followed by filtration. After separating the water, 500 parts of ion-exchanged water was newly added to make the slurry uniform and the water was washed. After that, dehydration and washing with water were repeated several times again, and the solid content was separated by filtration, followed by drying at 50 ° C. for 24 hours in a drier to obtain toner particles.

To 100 parts of the toner particles obtained as described above, 0.3 part of a hydrophobized Coguchi Darcilica (trade name: R-927, manufactured by Nippon Aerosil Co., Ltd.) was added, and the mixture was mixed with Hensil Mixer. And mix using one to prepare the toner. Was. When the volume resistivity of the toner thus obtained was measured, it was 1.8 × 10ΗΩ · cm.

When the fixing temperature was measured using the toner obtained as described above, it was 130 ° C. In addition, the preservability of this toner was very good (evaluation = =). Table 4 shows the results. In other image evaluations, an image having a high image density, no capri and glares, and an extremely good resolution was obtained.

[Example 16]

In Example 15, except that styrene added during the polymerization and a 1% aqueous solution of potassium persulfate were added at the time of the polymerization conversion of the core component monomer composition of 93%, In the same manner as in Example 15, a polymerization toner was obtained. Table 4 shows the measurement results of the particle size, fixing temperature, and storage stability of the obtained toner particles.

[Example 17]

Example 15 was the same as Example 15 except that the amount of styrene added during the polymerization was changed to 20 parts and the amount of the 1% aqueous solution of potassium persulfate was changed to 2 parts. Polymerized toner was obtained by the same operation method. Table 4 shows the measurement results of the particle size, fixing temperature, and storage stability of the obtained toner particles.

[Example 18]

A polymerization toner was obtained in the same manner as in Example 15 except that in Example 15 the methanol added during the polymerization was changed to acetate. Table 4 shows the measurement results of the particle size, fixing temperature, and storage stability of the obtained toner particles.

[Example 19]

In Example 15, the first step (the step of producing the core component polymer particles) When the polymerization conversion reaches 80%, 10 parts of methyl methacrylate (calculated Tg = 105 ° C) is added as a monomer for the first sealing component did. Next, 1 part of a 1% aqueous solution of potassium persulfate was added, and after the reaction was continued for 1 hour, 20 parts of methanol was added. After 10 minutes, 5 parts of styrene (calculated Tg = 100 ° C) was added to the reactor as a monomer for the second sealing component, and then 0.5% calcium persulfate was added. Then, 0.5 part of an aqueous solution of sodium hydroxide was added, and thereafter the reaction was continued for 5 hours to complete the reaction, thereby obtaining polymer particles (toner particles). Table 4 shows the measurement results of the particle size, fixing temperature, and storage stability of the obtained toner particles.

[Example 20]

Example 15 was the same as Example 15 except that 0.01 part of a charge control agent (Bontron E-84, manufactured by Orient Chemical Co.) was added to the styrene added during the polymerization. A polymerized toner was obtained in the same manner as in Example 15. Table 4 shows the measurement results of the particle size, fixing temperature, and storage stability of the obtained toner particles.

[Comparative Example 5]

In Example 15, polymerization was performed in the same manner as in Example 15 except that methanol, styrene, and an aqueous solution of persulfuric acid realm were not added during the polymerization. A toner was obtained. Table 4 shows the measurement results of the particle size, fixing temperature, and storage stability of the obtained toner particles. The shelf life evaluation of the resulting polymerized toner was X, which was poor. Table 4

[Example 21]

A polymerized toner was obtained in the same manner as in Example 15 except that 5 parts of phthalocyanine blue (GNX manufactured by Sumitomo Chemical Co., Ltd.) was used instead of carbon black. Table 5 shows the measurement results of the particle size, fixing temperature, storability, and 0 HP permeability of the obtained toner particles.

[Comparative Example 6]

A polymerized toner was obtained in the same manner as in Comparative Example 5, except that 5 parts of phthalocyanine blue (GNX manufactured by Sumitomo Chemical Co., Ltd.) was used instead of 5 parts of the carbon black. Table 5 shows the measurement results of the particle diameter, fixing temperature, storability, and OHP transmittance of the obtained toner particles.

[Comparative Example 7]

In Comparative Example 5, 5 parts of phthalocyanine (GNX, manufactured by Sumitomo Chemical Co., Ltd.) was used instead of 5 parts of carbon black, and 85 parts of styrene and n-butyl acrylate were used as monomer components. G 15 parts (copolymer The polymerized toner was obtained in the same manner as in Comparative Example 5, except that the calculated Tg was changed to Tg = 66 ° C.). Table 5 shows the measurement results of the particle diameter, fixing temperature, storage stability, and OHP permeability of the obtained toner particles. Table 5

[Example 22]

In Example 15, tert-butylperoxy-2-ethylethylhexanoe was used in place of 2,2-azobisisoptilonitrile as the oil-soluble initiator used in the polymerization of the monomer composition for the core component. A polymerized toner was obtained in the same manner as in Example 15 except that the reaction mixture was used and the reaction temperature was 90 ° C. The resulting polymerized toner exhibited almost the same fixing temperature and storage stability as the polymerized toner obtained in Example 15. When the residual monomer amount was analyzed by the following method, the residual monomer amount of the polymerization toner of Example 15 was 69 ppm, whereas the residual monomer amount of the polymerized toner of Example 15 was 69 ppm. It was found that the residual monomer content of the polymerization toner was significantly reduced to 230 ppm. Table 6 shows the results.

Analysis of residual monomer amount The amount of residual monomer in the polymerization toner was measured by gas chromatography. 0.2 g of the polymerized toner of the sample was precisely weighed into 10 ml of Mesco flask, methanol was added to the marked line, and the mixture was allowed to permeate for 5 hours. Next, after insoluble matter was precipitated by centrifugation, the supernatant 1β1 was injected into the GC-MS to perform monomer analysis. GC—MS conditions below It writes in.

Column HP—1, 0.25 m mx 30 m, 1 μm

Oven Temperature rises from 50 ° C to 260 ° C in 10 minute heating rate I N J. 220 ° C

D E T. 260 ° C

[Examples 23 to 25]

Polymerized toners were obtained in the same manner as in Example 22 except that the type of the oil-soluble initiator was changed to the one shown in Table 6, and the polymerization temperature was changed to the one shown in Table 6. Each of the obtained polymerized toners exhibited substantially the same fixing temperature and storage stability as the polymerized toner obtained in Example 15.

Table 6 shows the types of oil-soluble initiators, the amount of residual monomer, and the results of measurements such as odor determination. Table 6

Example

22 23 24 25 t-Butyl-peroxy succindifucamide t-Hexyl vel oxy tert-butyl propyl oxy oxy oil

Sex

Open 10 hours half life

Start 72 66 70 77 Temperature

(° C)

Molecular weight 216 234 244 160 Polymerization temperature (° C) 90 85 90 95 Polymerization state 〇〇〇球 Sphericity 1.1 1.1 1.1 1.2 Odor judgment 〇〇〇トナー Toner water content (%) 0.1 0.1 0.1 0.2 Toner heating loss (%) 1.1 1.0 0.8 0.9 Residual monomer (ppm) 230 420 340 400 / J

46

(Footnote)

(1) Moisture content was measured with a force-flush moisture meter.

(2) Heat loss was measured by measuring the rate of change in weight at 105 ° C. for 1 hour. (3) As for the odor, 10 people were randomly selected, and when more than half of the people felt the odor, it was marked as X, and when there was no one, it was marked as 〇. Industrial applicability

ADVANTAGE OF THE INVENTION According to the manufacturing method of this invention, the toner for electrostatic image development which has a low fixing temperature and favorable 0HP transmittance | permeability, and was excellent in preservability is provided.

Claims

The scope of the claims

1. A monomer composition containing at least a polymerizable monomer and a colorant is subjected to suspension polymerization in an aqueous dispersion medium containing a dispersant, so that the colored polymer particles are In the method for producing a toner for developing an electrostatic image,

(1) A monomer for a core component containing at least one monomer for a core component and a colorant to form a polymer having a glass transition temperature of 80 ° C or lower in an aqueous dispersion medium. A first step of subjecting the composition to suspension polymerization until the polymerization conversion of the monomer becomes 80% or more to form colored polymer particles serving as a core component; and

(2) At least one kind of sealant that forms a polymer having a glass transition temperature higher than the glass transition temperature of the polymer of the core component in the reaction system containing the colored polymer particles serving as the core component. A monomer or a monomer composition for a shell component containing the monomer and a water-soluble radical initiator are added to carry out a polymerization reaction, and the surface of the colored polymer particles serving as a core component is added. In the second step of forming a polymer coating layer serving as a shell component at least in two steps, a core component is composed of 40 to 99% by weight and a shell component of 1 to 60% by weight. A method for producing a toner for developing an electrostatic image, characterized by producing encapsulated colored polymer particles having a core-shell structure.

2. In the second step, the monomer for the seal component or the monomer composition for the seal component containing the monomer is added to the reaction system more than the colored polymer particles as the core component. 2. The production method according to claim 1, wherein the polymerization reaction is carried out by adding to a water suspension of droplets having a small number average particle diameter and conducting the polymerization reaction.

3. In the second step, together with the monomer for a shell component or the monomer composition for a shell component containing the monomer, the solubility in water at 20 ° C. is 5 wt. The production method according to claim 1, wherein the polymerization is carried out by adding at least an organic solvent in an amount of at least 1%.

3. The process according to claim 1, wherein the monomer for the sealing component is a monomer having a solubility in water at 20 ° C. of 0.1% by weight or more.

5. The production method according to claim 2, wherein the monomer for the shell component is a monomer having a solubility in water at 20 ° C. of less than 0.1% by weight.

6. In the second step, a water-soluble radical initiator is added to the reaction system simultaneously with or after the addition of the monomer for the shell component or the monomer composition for the shell component containing the monomer. The production method according to any one of claims 1 to 5, wherein the polymerization is carried out by adding.

7. The production method according to any one of claims 1 to 6, wherein the monomer composition for a shell component contains a monomer for a shell component and a charge controlling agent.

8. A water-based dispersion medium is used as a dispersing agent to form a poorly water-soluble metal hydroxide metal salt formed by the reaction of a water-soluble polyvalent metal salt with an alkali metal hydroxide in the aqueous phase. The production method according to any one of claims 1 to 7, wherein the production method contains a Lloyd.

9. In the second step, after adding an organic solvent to the reaction system, 4. The production method according to claim 3, wherein the polymerization is carried out by adding a monomer for a shell component or a monomer composition for a shell component containing the monomer.

10. In the second step, (i) before adding an organic solvent to the reaction system, before adding an organic solvent, a monomer or a monomer for a first sealant having a solubility in water at 20 ° C of 0.1% by weight or more is added. The monomer composition for the first shell component containing the monomer is added to carry out a polymerization reaction. Then, (ii) the solubility in an organic solvent and water at 20 ° C is added to the reaction system. 4. The polymerization according to claim 3, wherein the polymerization is carried out by adding a monomer for the second shell component or a monomer composition for the second shell component containing the monomer in an amount of less than 0.1% by weight. Production method.

11. Simultaneous with or after the addition of the monomer for the first shell component or the monomer composition for the first shell component containing the monomer, a water-soluble radical initiator is added. The production method according to claim 10, wherein the polymerization is carried out.

12. A water-soluble radical initiator is added simultaneously with or after the addition of the monomer for the second shell component or the monomer composition for the second shell component containing the monomer. The production method according to claim 10, wherein the polymerization is carried out.

13. The production method according to any one of claims 1 to 12, wherein in the first step, the monomer for the core component is polymerized with an oil-soluble polymerization initiator.

14. The production method according to any one of claims 1 to 13, wherein the core component monomer composition contains an oil-soluble polymerization initiator.

15. The oil-soluble initiator is an organic peroxide having a 10-hour half-life temperature of 60 to 80 ° C. and a molecular weight of 250 or less, 13 or 14. The manufacturing method as described.

16. A monomer composition containing at least a polymerizable monomer and a colorant is subjected to suspension polymerization in an aqueous dispersion medium containing a dispersant, whereby the colored polymer particles are In the method for producing a toner for developing an electrostatic image,

(2) At least one kind of sealant which forms a polymer having a glass transition temperature higher than the glass transition temperature of the polymer of the core component in the reaction system containing the colored polymer particles serving as the core component. The monomer for the component or the monomer composition for the shell component containing the monomer is converted into an aqueous suspension of droplets having a smaller number average particle diameter than the colored polymer particles serving as the core component. At least in two steps in the second step of forming a polymer coating layer that becomes a xyl component on the surface of the colored polymer particles that form the core component. Thus, the present invention is characterized in that a force-pusel type colored polymer particle having a core-shell structure composed of 40 to 99% by weight of a core component and 1 to 60% by weight of a shell component is produced. A method for producing a toner for developing a charge image.

17. In the first step, the monomer for the core component is polymerized with an oil-soluble polymerization initiator, and in the second step, the monomer for the seal component is polymerized. 17. The method according to claim 16, wherein the compound is polymerized with a water-soluble radical initiator.

18. The method according to claim 16 or 17, wherein the monomer for the shell component is a monomer having a solubility in water at 20 ° C of less than 0.1% by weight.

1 9. The aqueous dispersion medium, as a dispersant, is a poorly water-soluble metal hydroxide colloid formed by the reaction of a water-soluble polyvalent metal salt with an alkali metal hydroxide in the aqueous phase. The method according to any one of claims 16 to 18, wherein the method comprises:

20. By subjecting a monomer composition containing at least a polymerizable monomer and a colorant to suspension polymerization in an aqueous dispersion medium containing a dispersant, the colored polymer particles In the method for producing a toner for developing an electrostatic image,

(1) A monomer for a core component containing at least one kind of a monomer for a core component and a colorant, which forms a polymer having a glass transition temperature of 80 ° C or lower in an aqueous dispersion medium. A second step of subjecting the composition to suspension polymerization until the polymerization conversion of the monomer becomes 80 or more to form colored polymer particles serving as a core component; and

(2) In the reaction system containing the colored polymer particles serving as the core component, at least one kind of shell component for forming a polymer having a glass transition temperature higher than the glass transition temperature of the polymer of the core component. A polymerization reaction is carried out by adding an organic solvent having a solubility in water at 20 ° C of 5% by weight or more together with the monomer or the monomer composition for a shell component containing the monomer. Coating of polymer as shell component on surface of colored polymer particles as core component By at least two steps of the second step of forming a layer, capsule-shaped colored polymer particles having a core-shell structure composed of 40 to 9.9% by weight of a core component and 1 to 60% by weight of a sealer component are obtained. A method for producing a toner for developing an electrostatic charge image, characterized by being produced.

21. In the first step, the monomer for the core component is polymerized with an oil-soluble polymerization initiator, and in the second step, the monomer for the silicone component is polymerized with a water-soluble radical initiator. The production method according to claim 20, wherein

22. The production method according to claim 20 or 21, wherein the monomer for a sealing component is a monomer having a solubility in water at 20 ° C of less than 0.1% by weight.

2 3. The aqueous dispersion medium is a poorly water-soluble metal hydroxide formed by the reaction of a water-soluble polyvalent metal salt and an alkali metal hydroxide in the aqueous phase as a dispersant. The production method according to any one of claims 20 to 22, wherein the production method includes a metal.

24. In the second step, (i) before adding an organic solvent to the reaction system, a monomer for the first sealing component having a solubility in water at 20 ° C of 0.1% by weight or more is added. Alternatively, the polymerization reaction is carried out by adding the monomer composition for the first shell component containing the monomer, and then (ii) adding an organic solvent to the reaction system, 20. A polymerization method comprising adding a monomer for a second shell component having a solubility in water of less than 0.1% by weight or a monomer composition for a second shell component containing the monomer. 24. The production method according to any one of 23 to 23.

25. A toner for developing an electrostatic charge image obtained by the production method according to any one of claims 1 to 25.

26. A storage means (2) for storing the toner for developing an electrostatic image according to claim 25, a supply means (2) for supplying the toner stored in the storage means, an image carrier (3), and an opposite face to the image carrier. Developing means for developing the electrostatic latent image formed on the image carrier using the toner supplied by the supply means, and transfer means for transferring the developed toner image to a material to be transferred An image forming apparatus comprising: