JP2000029241A - Production of electrophotographic toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a producing method of an electrophotographic toner by which the bleeding of a low melting point material such as an offset preventing agent to the particle surface caused by conventional heat treatment can be prevented while the required shape and surface state of the toner particles from an irregular form to a spherical form are controlled by simple dry heat treatment. SOLUTION: In this producing method, toner particles are heat-treated by using a heat treating device equipped with a heat treating space 1, hot air supply nozzle 8 to supply hot air 2 to the heat treating space 1, and dispersion nozzles 3 to supply the toner particles containing a binder resin to the heat treating space 1 so as to disperse the particles in the hot air 2. Then, the toner particles dispersed in the hot air 2 are cooled in a cooling and trapping hopper 12. The inner diameter D of the hot air supply nozzle 8 and the distance X from the crossing point M of the extended line of the center line of the dispersion nozzles 3 and the extended plane of the inner wall of the hot air supply nozzle 8 to the opening of the cooling and trapping hopper 12 are made to satisfy X/D <=0.6 or the flow rate of the hot air 2 is made to >=2.55 m/s.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a one-component developer or a two-component developer used for developing an electric latent image or a magnetic latent image in an electrophotographic apparatus, for example, an electrophotographic copying machine and a printer. The present invention relates to a method for producing a surface-modified toner for electrophotography used in a component developer.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus such as a copying machine or a printer, various toners have been used as a developer for developing an electrostatic latent image formed on a photosensitive member.

[0003] As a conventional toner, for example, a colorant, a charge control agent, an anti-offset agent and the like are melt-kneaded with a thermoplastic resin, then solidified by cooling, and then pulverized and classified to form toner particles. Toners produced by the resulting grinding method are known.

Further, a charge control agent is mixed and suspended (dispersed) in water together with a polymerizable monomer, a polymerization initiator, a colorant, and the like.
A suspension polymerization method in which a polymerizable monomer is polymerized in a suspension; a charge controlling agent is blended with a colorant together with a synthetic resin, and the mixture is melted. The obtained melt is suspended in a non-solvent medium. There is also known a toner obtained by a wet method typified by a suspension granulation method in which granulation is performed.

In recent years, electrophotographic processes have been used in many fields such as printers, facsimile machines, color copiers, and high-speed copiers. Toners used in the electrophotographic process, that is, electrophotographic toners, depending on their respective fields and functions, those with high fluidity,
What has various characteristics, such as control of electrification, is required.

[0006] From these viewpoints, a toner in which the surface of toner particles is modified, that is, a so-called surface-modified toner has been studied. Examples of the surface-modified toner include a surface-modified toner in which toner particles are made spherical by mechanical shearing force or heat treatment to improve fluidity; fine particles having various functions represented by a charge control agent are used as toner core particles. Surface-modified toner fixed to the surface in a dry or wet manner, and sufficient functions are efficiently imparted to the toner core particles by the fixed fine particles; a toner obtained by coating the surface of the core particles having a low softening temperature with hardened resin fine particles. Numerous materials such as surface-modified toners having improved durability and fixing properties of core particles have been studied.

Japanese Patent Application Laid-Open No. Hei 3-179363 discloses a method of spheroidizing a toner produced by a pulverization method containing waxes by heat treatment, in order to prevent aggregation of the toners at the time of the heat treatment, by adding an inorganic substance to the toner surface in advance. There has been proposed a method for producing a toner using particles having fine particles attached thereto.

Japanese Patent Application Laid-Open No. 9-31501 discloses that toner base particles having at least a colorant dispersed in a binder resin and adjusted to a predetermined particle size distribution are subjected to a surface modification treatment with hot air. A method for producing a toner which is subjected to a rapid cooling process immediately thereafter has been proposed.

Further, Japanese Patent Application No. 9-19759 filed by the present applicant is disclosed.
No. 0 describes a toner in which modified fine particles are fixed or formed into a film on the surface of a core particle by heat treatment.
A heat-treated surface-modified toner in which the shape of toner particles is maintained in an irregular shape by controlling the T specific surface area value, and a method for producing the same are described.

[0010]

However, in a known method of modifying the surface of toner particles, for example, a method of making toner particles spherical by using mechanical impact force, a sufficient degree of sphericity is not obtained. In this case, the toner particles themselves are pulverized, and a large amount of fine powder is generated. As a result, problems such as loss of uniformity of charging and generation of fog on a white background occur.

Further, when only normal hot air treatment is applied to the toner particles, problems such as seepage of the low-melting substance, scattering due to fusion of the particles, and generation of white background fog occur. As a result, the heat treatment temperature is restricted, and when trying to achieve sufficient spheroidization, fusion and aggregation of toner particles occur.

For this reason, Japanese Patent Application Laid-Open No. Hei 3-179363 proposes a method of solving the problem by adding inorganic fine particles to the particle surface. However,
In these methods, the deterioration of the fixing performance to the paper surface and the deterioration of the offset prevention effect are unavoidable.

Also, Japanese Patent Application Laid-Open No. Hei 9-31501 proposes that cooling air is introduced immediately after the heat treatment to perform rapid cooling. However, in this proposal,
The velocity of the hot air that heats the toner particles is low, and the distance between the position where the toner particles are subjected to the hot air treatment and the position where the toner particles are rapidly cooled is long. For this reason, it is difficult to control the shape of the obtained toner to an arbitrary shape from an irregular shape to a spherical shape, and particularly, when a low melting point substance or the like is contained in the toner particles, fusion and aggregation of the toner particles are performed. Is very likely to occur.

The present invention has been made in view of the above-mentioned conventional problems, and has as its object to control the required shape and surface state of toner particles from an irregular shape to a spherical shape by a simple dry heat treatment. It is another object of the present invention to provide a method for producing an electrophotographic toner capable of preventing a low-melting substance such as an anti-offset agent from seeping into the particle surface by a conventional heat treatment. Another object of the present invention is to use, as toner particles, mixed particles obtained by adhering and dispersing modified fine particles having various functions such as a charge control agent on the surface of toner core particles, and from fixation to complete film formation. An object of the present invention is to provide a method for producing an electrophotographic toner in which the surface is controlled to have an arbitrary shape and state up to the formation of the toner, and the surface of the core particle is not modified and the modified fine particles are not separated and separated.

[0015]

Means for Solving the Problems The present inventors have conducted intensive studies on a method for producing an electrophotographic toner capable of achieving the above-mentioned object, and found that the toner in a predetermined state (such as a shape and a state of adhesion of modified fine particles) is obtained. In order to obtain the particles, it is necessary to perform heat treatment using hot air having a sufficient flow velocity, or to find that it is essential that the cooling immediately after the heat treatment be performed in the vicinity of the position where the toner particles are dispersed in the hot air, The present invention has been completed.

That is, in the method for producing an electrophotographic toner according to claim 1 of the present invention, in order to solve the above-mentioned problems, a heat treatment space in which toner particles containing a binder resin are heat-treated;
After the heat treatment of the toner particles using a heat treatment apparatus having a hot air supply port for flowing hot air into the heat treatment space, and a toner particle supply port for supplying the heat treatment space so as to disperse the toner particles in the hot air, A method for producing an electrophotographic toner, wherein the toner particles dispersed in hot air are cooled in a cooling container provided on a downstream side, wherein an inner diameter D of a hot air supply port and an extension of a center line of the toner particle supply port are provided. And the distance X from the intersection of the hot air supply port and the extended surface of the inner wall to the end of the cooling vessel on the heat treatment space side is set so that X / D ≦ 0.6.

According to the above method, the toner particles can be uniformly dispersed in the hot air, the aggregation of the toner particles can be prevented, and the modified fine particles in the state where the amorphous toner core particles are maintained in the irregular shape are maintained. By fixing the toner particles and smoothing the surface of the toner particles, the toner for electrophotography can be controlled to an arbitrary shape. When X / D is larger than 0.6, it is difficult to control the electrophotographic toner to have an arbitrary shape, and the possibility of aggregation of toner particles increases.

The toner particle supply port desirably disperses the toner particles by spraying the toner particles. Preferably, the cooling container cools the toner particles by cooling air.
Further, in the above method, it is desirable to control the flow velocity of the hot air at the hot air supply port to 2.55 m / s or more. Thereby, it is possible to more reliably realize prevention of aggregation of the toner particles and control of the toner particles after heat treatment to an arbitrary shape.

According to a second aspect of the present invention, there is provided a method of manufacturing an electrophotographic toner, in order to solve the above-mentioned problems, a heat treatment space in which toner particles containing a binder resin are heat-treated, and hot air flowing into the heat treatment space. After heat-treating the toner particles using a heat treatment apparatus having a hot-air supply port and a toner-particle supply port that supplies the toner particles to the heat treatment space so as to be dispersed in the hot air, cooling provided downstream of the heat treatment space A method for producing an electrophotographic toner for cooling the toner particles dispersed in hot air in a container, wherein the flow rate of hot air in a hot air supply port is controlled to 2.55 m / s or more.

According to the above method, the toner particles can be uniformly dispersed in the hot air, the aggregation of the toner particles can be prevented, and the modified fine particles in the state where the amorphous toner core particles are maintained in the irregular shape are maintained. By fixing the toner particles and smoothing the surface of the toner particles, the toner for electrophotography can be controlled to an arbitrary shape. If the flow velocity of the hot air at the hot air supply port is less than 2.55 m / s, the toner particles cannot be supplied in a sufficiently dispersed state in the hot air, and there is a high possibility that the toner particles will aggregate.

According to a third aspect of the present invention, there is provided a method for producing a toner for electrophotography according to the first aspect.
Alternatively, in the method for producing an electrophotographic toner according to item 2, the number of toner particle supply ports is four or more.

According to the above method, collisions and aggregation of toner particles and pulverization of toner particles are remarkably generated as compared with the case where the number of toner particle supply ports is three or less (particularly two cases). In addition, the processing capacity can be significantly improved by improving the supply amount of the toner particles.

When the number of toner particle supply ports is three or less, collision, aggregation, and pulverization of the toner particles tend to occur before the toner particles are dispersed from the toner particle supply port. In addition, since the supply amount of the toner particles from one toner particle supply port is increased, adjacent particles are aggregated, and a problem easily occurs in the manufactured electrophotographic toner.

The heat treatment apparatus preferably has a cylindrical portion (reflux portion) for supplying the toner particles as a cylindrical fluid to the plurality of toner particle supply ports.
In order to create a uniform flow of toner particles, the plurality of toner particle supply ports are arranged at equal intervals to each other, and the toner particle supply direction of the adjacent toner particle supply ports (the direction in which the toner particles are sent out). ) Is 0 °
Is preferably set to be more than 45 °. Further, it is preferable that a uniform amount of the material is spray-dispersed from the plurality of toner particle supply ports.

According to a fourth aspect of the present invention, there is provided a method of manufacturing an electrophotographic toner, the first aspect of the invention being intended to solve the above-mentioned problems.
4. The method for producing an electrophotographic toner according to any one of items 3 to 3, wherein the heat treatment apparatus further includes a rectifying gas inlet for introducing a rectifying gas for adjusting a flow of the toner particles in the heat treatment space. And

According to the above method, a rectifying gas inlet for introducing a rectifying gas for adjusting the flow of the toner particles supplied to the heat treatment apparatus is provided separately from the toner particle supply port, so that the toner particles can be transported. The carrier gas for supplying the toner particles introduced from the particle supply port suppresses the generation of a vortex in the hot air supply port and the vicinity thereof, and the generated vortex causes the toner particles to reach the inner wall of the apparatus surrounding the heat treatment space and the hot air supply port. Adhesion and contamination can be prevented. As a result, when the type of the electrophotographic toner to be manufactured is switched, it is possible to prevent the electrophotographic toner from being contaminated by a residue or a fusion product of the previously used toner particles.

According to a fifth aspect of the present invention, there is provided a method of manufacturing a toner for electrophotography according to the first aspect.
5. The method for producing an electrophotographic toner according to any one of items 4 to 4, wherein heat treatment and cooling are performed in a dry gas atmosphere.

According to the above-mentioned method, for example, a dry gas atmosphere is formed in the heat treatment space by using a dry gas as a carrier gas for supplying toner particles and a rectifying gas introduced into the heat treatment space as required. Formed and heat-treated in a dry gas atmosphere. Also, for example, a dry gas atmosphere is formed in the cooling container by sending the cooled dry gas as cooling air into the cooling container, and cooling is performed in the dry gas atmosphere. This can prevent the heat treatment and cooling from being affected by the temperature and humidity. As a result, thermal efficiency is improved, heat treatment with low energy is possible, and dew condensation during cooling can be prevented, and aggregation of collected electrophotographic toner can be prevented.

The method for producing an electrophotographic toner according to claim 6 of the present invention is intended to solve the above-mentioned problems.
6. The method for producing an electrophotographic toner according to any one of items 5 to 5, wherein mixed particles obtained by adhering modified fine particles to the surface of toner core particles containing a binder resin are used as toner particles.

According to the above method, the modified fine particles can be fixed or formed into a film on the surface of the toner core particles to modify the toner core particles. The immobilization or film formation of the modified fine particles not only makes it possible to heat the internal toner core particles to form a sphere, but also heats only the vicinity of the surfaces of the modified fine particles and the toner core particles. It is also possible to maintain the irregular shape of the toner core particles. Therefore, it is possible to manufacture a modified electrophotographic toner having an arbitrary shape from an irregular shape to a spherical shape.

According to a seventh aspect of the present invention, there is provided a method of manufacturing a toner for electrophotography according to the sixth aspect of the present invention.
In the method for producing an electrophotographic toner described above, the modified fine particles are thermoplastic resin fine particles having a glass transition temperature higher than the glass transition temperature of the toner core particles.

According to the above-described method, since the thermoplastic resin fine particles are used as the modified fine particles, the fixing or film forming state without peeling or detachment by the thermal fusion between the toner core particles and the thermoplastic resin fine particles. Can be obtained. Further, since the glass transition temperature of the thermoplastic resin particles is higher than the glass transition temperature of the toner core particles, an electrophotographic toner having excellent storage stability can be obtained.

According to the present invention, there is provided a method for producing an electrophotographic toner according to the present invention.
The method for producing an electrophotographic toner as described above, wherein the volume resistivity of the modified fine particles is 1 × 10 ⁶ Ω · cm or more.

A volume resistance value of 1 × 10 ^{6 on the} surface of the toner particles
When a low-resistance substance (for example, a conductive material) having a resistance of less than Ω · cm is present, charges are concentrated on the low-resistance substance in a developing process or a transfer process in an electrophotographic method, and disadvantages such as charge leakage and transfer failure are caused. May cause phenomena. According to the above method, since the volume resistivity of the modified fine particles is 1 × 10 ⁶ Ω · cm or more, these phenomena can be avoided.

According to a ninth aspect of the present invention, there is provided a method of manufacturing an electrophotographic toner according to the sixth aspect.
In the method for producing an electrophotographic toner described in the above, the modified fine particles are thermoplastic resin fine particles having a charge-imparting function.

According to the above method, by using thermoplastic resin fine particles having a charge-imparting function as modified fine particles with respect to toner core particles containing no charge-imparting agent having a charge-imparting function, the toner core particles As compared with a case where a charge-imparting agent is contained, the same charge performance can be imparted by allowing a small amount of thermoplastic resin fine particles to exist on the surface of the toner core particles. Further, by adjusting the type and amount of the thermoplastic resin fine particles, it is possible to control the polarity and control the charging performance with the same toner core particles. As a result, an electrophotographic toner can be manufactured at a low cost in terms of both material costs and manufacturing costs.

[0037]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. The method for producing an electrophotographic toner according to the present invention includes a heat treatment space in which toner particles containing a binder resin are heat-treated, a hot air supply port for flowing hot air into the heat treatment space, and a heat treatment so as to disperse the toner particles in the hot air. After heat-treating the toner particles using a heat-treating device having a toner-particle supply port for supplying the space, a method of cooling the toner particles dispersed in hot air in a cooling container provided on the downstream side of the heat-treating space. is there.

The method for producing an electrophotographic toner according to the present invention is characterized in that the cooling container is provided by measuring the inner diameter D of the hot air supply port and the intersection of the extension of the center line of the toner particle supply port and the extension of the inner wall of the hot air supply port. And the distance X to the heat treatment space side end in
X / D ≦ 0.6 or the flow rate of hot air at the hot air supply port is controlled to 2.55 m / s or more.

In the heat treatment in the present invention, the surface of the toner particles is smoothed or the shape of the toner particles is made spherical.
Alternatively, mixed particles obtained by adhering modified fine particles to the surface of toner core particles containing a binder resin are used as toner particles, and the modified fine particles adhered to the toner core particle surfaces are fixed or formed on the toner core particle surfaces. It is for making it.

The toner particles or toner core particles in the present invention contain a binder resin. As the binder resin, all known binder resins used for toner can be used, and polystyrene, styrene- (meth) acrylate copolymer (styrene-acryl copolymer), styrene -Acrylonitrile copolymer, styrene-maleic anhydride copolymer, styrene- (meth) acrylate-maleic anhydride copolymer, polyvinyl chloride, polyolefin resin, epoxy resin, silicone resin, polyamide resin, polyurethane resin, Urethane-modified polyester resin, acrylic resin and the like can be used. These resins can be used alone or as a mixture of two or more kinds, and can also be used as two or more kinds of block polymers or graft polymers. Also,
The molecular weight distribution of the binder resin is a single peak (one peak) distribution or a double peak (two peaks) distribution, and is not particularly limited.

Further, a function-imparting agent for imparting various functions may be mixed and dispersed in the binder resin in the toner particles or the toner core particles. The function-imparting agent is not particularly limited, and various known function-imparting agents,
For example, charge control agents such as azo dyes, carboxylic acid metal complexes, quaternary ammonium compounds, and nigrosine dyes; coloring agents such as carbon black, iron black, nigrosine, benzene yellow, and phthalocyanine blue; polyethylene, polypropylene, and ethylene -An anti-offset agent such as a propylene polymer. These function-imparting agents may be used alone or in combination of two or more. Further, the toner particles or the toner core particles may contain a magnetic powder such as ferrite.

The particle size of the toner particles or the toner core particles may be in the range of the particle size in the case where the toner particles are usually used as a powder toner, and the volume average particle size is suitably in the range of 5 μm to 15 μm. is there.

As the modified fine particles which are adhered to the surface of the toner core particles to be fixed or formed into a film, those having various functions such as a charge controlling agent, a fluidizing agent, a coloring agent and an anti-offset agent are used. Functional fine particles such as thermoplastic resin fine particles and inorganic fine particles can be used.However, when thermoplastic resin fine particles are used, heat-sealing of the toner core particles and the thermoplastic resin fine particles allows for immobilization without peeling or detachment. An electrophotographic toner in a film-forming state can be obtained.

As the inorganic fine particles, specifically, silicon oxide, boron nitride, titanium oxide, alumina, magnetite and the like can be used. Further, those obtained by subjecting inorganic fine particles to a surface treatment such as hydrophobization with a silane coupling agent can also be used. The anti-offset agent is for imparting an anti-offset effect to the electrophotographic toner. As the anti-offset agent, waxes such as a low melting point thermoplastic resin can be used, and specifically, polyethylene, polypropylene, ethylene-propylene polymer, ethylene-vinyl acetate copolymer, ethylene-ethyl Acrylate copolymer,
An ionomer having a polyethylene skeleton or the like can be used.

Specific examples of the thermoplastic resin fine particles include methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, and butyl methacrylate, as well as styrene, p-methylstyrene, sodium styrenesulfonate, vinylbenzyl chloride, and acrylic. A homopolymer or copolymer of a monomer (hereinafter, referred to as a monomer) such as an acid, 2- (dimethylamino) ethyl acrylate, methacrylic acid, and 2-methylaminoethyl methacrylate can be used.

A thermoplastic resin fine particle having a positive or negative charge imparting function (hereinafter, referred to as a charge imparting thermoplastic resin fine particle) functions as a charge control agent and is therefore preferable. Examples of a method for obtaining the charge-imparting thermoplastic resin fine particles include a method of polymerizing the monomer using a polymerization initiator such as potassium persulfate, ammonium sulfate, or amidinopropane hydrochloride; an amino group, an amide group, and a carboxyl group. A method of copolymerizing a monomer having a polar group such as a sulfonic acid group (sulfo group) (hereinafter referred to as a polar monomer) with the monomer; a hydrogen atom of the polar group of the polar monomer A method in which a monomer obtained by substituting with a metal ion (hereinafter, referred to as a metal-substituted monomer) is copolymerized with the monomer; a monomer containing a fluorine atom (hereinafter, referred to as a fluorine-containing monomer) Is copolymerized with the above-mentioned monomer. As the polar monomer, a monomer having a carboxyl group such as methacrylic acid is preferable. Also,
The metal-substituted monomer is preferably a monomer obtained by substituting a carboxyl group-containing monomer such as methacrylic acid for a hydrogen atom of the carboxyl group with a metal ion such as a zinc ion.

The charge-providing thermoplastic resin fine particles preferably contain, as at least a part of the components, thermoplastic resin fine particles containing fluorine in the molecular structure of the polymer. By including fluorine in the thermoplastic resin particles as described above, it is possible to obtain an electrophotographic toner having high negative chargeability and charge rising characteristics. In particular,
In the case of a contact charging method using a charging blade or the like, there has been a problem that a sufficient charge amount cannot be obtained. However, by incorporating fluorine, this problem can be solved. Further, the obtained electrophotographic toner has a small influence of the environment such as temperature and humidity, particularly a change in the charge amount under an environment such as a high temperature and high humidity state, and can maintain a stable charge amount.

The charge-giving thermoplastic resin fine particles preferably contain at least a part of thermoplastic resin fine particles having a carboxyl group in the molecular structure of the polymer. By including a component having a carboxyl group (for example, polymethacrylic acid chain) in the thermoplastic resin fine particles, it is possible to obtain an electrophotographic toner having high negative chargeability and charge rising characteristics.
In particular, there has been a problem that a sufficient charge amount cannot be obtained in the case of a contact charging method using a charging blade or the like. However, by containing a carboxyl group, this problem can be solved.

The fine particles of the charge-imparting thermoplastic resin are prepared by substituting a metal atom such as a zinc ion for a hydrogen atom of a hydrophilic group such as a carboxyl group or a sulfonic acid group and blocking the metal substituent in the polymer molecular structure. It is preferable to include the thermoplastic resin fine particles contained in at least a part of the components. Thermoplastic resin particles having a hydrophilic group are relatively easily affected by the environment such as temperature and humidity. However, by using thermoplastic resin fine particles having a metal substituent in which a hydrogen atom of a hydrophilic group is replaced with a metal ion, while maintaining high negative chargeability and charge start-up characteristics, the effects of environment such as temperature and humidity, In particular, it is possible to obtain an electrophotographic toner capable of maintaining a stable charge amount with a small change in the charge amount under an environment such as a high temperature and high humidity state.

The fine particles of the thermoplastic resin are preferably washed with water after polymerization. When using thermoplastic resin particles obtained by a polymerization method, hydrophilic impurities such as a polymerization initiator may be present on the surface of the obtained resin particles. According to the above method, these hydrophilic impurities can be removed by washing with water, and an electrophotographic toner which is less affected by the environment such as change in charge under high temperature and high humidity can be obtained.

The thermoplastic resin particles are preferably fine particles of a thermoplastic resin having a glass transition temperature higher than the glass transition temperature of the toner core particles. Further, the glass transition temperature of the thermoplastic resin fine particles is higher than the glass transition temperature of the toner core particles, and is in the range of 60C to 100C, and the glass transition temperature of the toner core particles is 40C to 7C.
It is particularly preferred that the temperature be in the range of 0 ° C. By producing an electrophotographic toner using toner core particles and thermoplastic resin particles having a glass transition temperature within the above range,
It is possible to obtain an electrophotographic toner which does not impair the fixing performance on paper and has excellent storage stability. When the glass transition temperature of the toner core particles exceeds 70 ° C, or the glass transition temperature of the thermoplastic resin fine particles exceeds 100 ° C,
The fixing performance of the electrophotographic toner on the paper surface is significantly deteriorated. Further, the glass transition temperature of the toner core particles is less than 40 ° C., or the glass transition temperature of
When the temperature is lower than 0 ° C., the strength of the electrophotographic toner (image portion) fixed on the paper surface is insufficient, and the electrophotographic toner is peeled off, or the electrophotographic toner is inferior in high-temperature storage stability and aggregates with each other.

It is preferable that the difference (absolute value) in the solubility parameter between the thermoplastic resin fine particles and the binder resin in the toner core particles is 2 or less. As described above, by setting the difference in the solubility parameter, which is an index of the compatibility between the resins, to 2 or less, the compatibility between the binder resin in the toner core particles and the fine particles of the thermoplastic resin is improved. As a result, it is possible to obtain an electrophotographic toner in which the thermoplastic resin particles are firmly fixed or formed into a film on the toner core particles, and peeling or detachment of the thermoplastic resin particles due to stress is prevented.

The modified fine particles are preferably made of a substance having a volume resistivity of 1 × 10 ⁶ Ω · cm or more.
More preferably, it is a thermoplastic resin fine particle having a volume resistance value of 1 × 10 ⁶ Ω · cm or more. Further, the volume resistivity of the modified fine particles is more preferably equal to or greater than the volume resistivity of the toner core particles. By using modified fine particles having a volume resistance value equal to or higher than the volume resistance value of the toner core particles, an electrophotographic toner with high transferability, little change in charge amount, and excellent charge stability during long-term use Can be obtained. Here, “the volume resistivity of the modified fine particles is equal to or greater than the volume resistivity of the toner core particles” means that the volume resistivity of the modified fine particles is α × 10 ^a and the volume resistivity of the toner core particles is When β × 10 ^b , a ≧
It means that the relationship of b is satisfied.

The volume average particle diameter of the modified fine particles is 1 μm
The following is preferred. In the method of the present invention,
It is preferable that the modified fine particles are held at least on the surface of the toner core particles before the heat treatment, and are uniformly dispersed on the surface of the toner core particles. Volume average particle size of modified fine particles is 1μ
m or less, the modified fine particles can be sufficiently held on the surface of the toner core particles by a weak force such as an intermolecular force or an electrostatic force acting between the toner core particles and the modified fine particles. Uniform dispersion of the modified fine particles into the particles can be achieved. If the volume average particle diameter of the modified fine particles exceeds 1 μm, the particles cannot be sufficiently held by weak force such as intermolecular force or electrostatic force.
Uniform dispersion of the modified fine particles on the surface of the toner core particles cannot be achieved.

The added amount of the modified fine particles is preferably 0.1 to 15 parts by weight based on 100 parts by weight of the toner core particles. By making the added amount of the modified fine particles 0.1 to 15 parts by weight, the function of the modified fine particles is sufficiently exhibited, and the modified fine particles are sufficiently fixed or formed on the toner core particles by heat treatment. Can be

Means for obtaining mixed particles by adhering and dispersing the above-mentioned modified fine particles on the surface of the toner core particles include mechanomill (trade name; manufactured by Okada Seiko Co., Ltd.), Ongmill (trade name; manufactured by Hosokawa Micron Corporation), Devices such as a hybridization system (trade name; manufactured by Nara Machinery Co., Ltd.) and a cosmo system (trade name; manufactured by Kawasaki Heavy Industries, Ltd.) can be used.

Next, an example of a manufacturing apparatus for performing the manufacturing method of the present invention and a method of performing the manufacturing method of the present invention using the manufacturing apparatus will be described with reference to FIGS.

As shown in FIGS. 1 and 2, a manufacturing apparatus for carrying out the manufacturing method of the present invention has a heat treatment space (hot air flow field) 1 in which toner particles containing a binder resin are heat-treated.
And a dispersion nozzle (toner particle supply port) 3 having a large number of circular openings for spraying the heat treatment space 1 so as to disperse the toner particles in the hot air 2, and supply the toner particles to the pipe 4 at a constant supply speed. A fixed-quantity feeder 5, a compressed gas generator 6 for sending compressed gas to the pipe 4 for sending the toner particles supplied to the pipe 4 to the dispersion nozzle 3, a hot air generator 7 for generating hot air 2, and a hot air generator A hot air supply nozzle (hot air supply port) 8 for flowing the hot air 2 generated in 7 into the heat treatment space 1 and a rectifying gas for introducing a rectifying gas for adjusting the flow of toner particles in the heat treatment space 1 into the heat treatment space 1. A heat treatment apparatus 10 having an inlet 9 is provided.

The dispersing nozzle 3 is tilted downward by about 45 degrees into two symmetrical positions on both sides of the hot air supply nozzle 8 and
Book is arranged. The number of the dispersing nozzles 3 depends on the processing capacity of the heat treatment apparatus 10 and the physical properties of the toner particles, and is not generally determined, but may be appropriately determined according to the processing capacity of the heat treatment apparatus 10. Specifically, when the processing capacity of the heat treatment apparatus 10 is 5 kg / h or less, it is preferable to use four dispersion nozzles 3,
When the processing capacity of the heat treatment apparatus 10 is 20 to 50 kg / h, it is preferable to use 10 to 20 dispersion nozzles 3.

The hot-air generator 7 may be any device that can generate the hot air 2, and for example, a sufusing system (trade name; manufactured by Nippon Pneumatic Co., Ltd.) or the like can be used.

The flow rate of the hot air 2 at the hot air supply nozzle 8 may be 2.55 m / s or more, but may be 5.09 m / s.
More preferably, it is s or more. Thereby, hot air 2
It can uniformly disperse the toner particles inside, prevent aggregation of the toner particles, and fix the modified fine particles while maintaining the irregular shape with respect to the irregular toner core particles, and smooth the surface of the toner particles. Thereby, the electrophotographic toner can be controlled to have an arbitrary shape.

Assuming that the flow velocity of the hot air 2 at the hot air supply nozzle 8 is V (m / s), V is defined by the following equation: V = F / A. However, in the above equation, F is the flow rate (m
³ / s) and A is the cross-sectional area (m ² ) of the hot air supply nozzle 8. Also, the cross section of the hot air supply nozzle 8 is circular, the cross-sectional area of the hot air supply nozzle 8 A (m ²⁾ can be calculated by the following formula A = πD ^2/4. However, in the above formula, D is the hot air supply nozzle 8
(M).

The temperature of the hot air 2 in the hot air supply nozzle 8 is preferably a temperature at which at least a part of the toner particles is softened, more preferably in the range of 150 ° C. to 500 ° C., and is stable in this temperature range. More preferably, it is controlled. With hot air 2 at a temperature lower than 150 ° C., the shape change of the toner particles due to heat hardly occurs. In addition, when the toner for electrophotography is used, fixing of the modified fine particles is not achieved, and detachment or detachment of the modified fine particles causes problems such as fusion to the photoreceptor and generation of fog. On the other hand, hot air 2 at a temperature exceeding 500 ° C. is not preferable because fusion of toner particles occurs.

In the heat treatment apparatus 10, the rectifying gas inlet 9
Are provided around the hot air supply nozzle 8. This suppresses the generation of a vortex in the lower portion of the hot air supply nozzle 8 or around the hot air supply nozzle 8 due to the inflow of the compressed gas or the cooling air 11 (described later). And hot air supply nozzle 8 can be prevented from adhering and contaminating. For this reason, it is possible to prevent the contamination of the toner particles due to the residue and the fused matter when the type of the electrophotographic toner to be manufactured is switched. The rectifying gas inlet 9 is only required to be capable of introducing a rectifying gas having a flow rate sufficient for rectification without extremely lowering the temperature of the hot air 2. It is preferable that the gap is formed in the range of 0.1 mm to 10 mm.

Although FIGS. 1 and 2 show an example in which the rectifying gas inlet 9 is provided around the hot air supply nozzle 8, the rectifying gas inlet 9 has the heat treatment space 1 and the cooling / collecting hopper 12. (Described later). In this case, the rectifying gas inlet 9 is preferably a gap provided between the heat treatment space 1 and the cooling / collecting hopper 12 within a range of 1 mm to 30 mm. Furthermore, it is also possible to omit the rectifying gas inlet 9 and to seal this part.

A cooling / collecting hopper (not shown) is provided below (downstream) the heat treatment space 1 in the heat treatment apparatus 10 for cooling and collecting the toner particles dispersed in the hot air 2 with the cooling air 11. A cooling container 12 is provided.

From the intersection M between the inner diameter D of the hot air supply nozzle 8 and the extension of the center line of the dispersion nozzle 3 and the extension of the inner wall of the hot air supply nozzle 8, the end of the cooling / collecting hopper 12 on the heat treatment space 1 side is determined. The distance X to the opening 12a is X / D ≦
It is set to be 0.6.

Immediately after the heat treatment, specifically, the toner particles are set at 0.1 mm so that the residence time of the toner particles in the heat treatment space 1 before introduction of the cooling / collecting hopper 12 is extremely short.
It is preferable to introduce into the cooling / collecting hopper 12 within seconds. That is, the time during which the toner particles stay in the heat treatment space 1, that is, the time during which the toner particles pass through the heat treatment space 1 before being introduced into the cooling / collecting hopper 12, may be within 0.1 second. preferable. The time required for the toner particles to pass through the heat treatment space 1 before being introduced into the cooling / collecting hopper 12 is more preferably within 0.012 seconds, and even more preferably within 0.006 seconds. As a result, the state change of the toner particles that have received the heat energy can be stopped in an arbitrary state and solidified by cooling, and it is possible to obtain an electrophotographic toner having a desired shape or state. If the time during which heat is applied to the toner particles becomes longer, it becomes difficult to smooth, fix or form a film only near the surface of the toner particles while maintaining the irregular shape, and the low melting point material such as an anti-offset agent may be used. It is not preferable because problems such as seepage occur.

The toner particles are cooled and collected by the hopper 1
The lower limit of the time required to pass through the heat treatment space 1 before being introduced into the heat treatment space 2 is not particularly defined. The time required for the toner particles to pass through the heat treatment space 1 before being introduced into the cooling / collecting hopper 12 may be changed for a desired state control. It must be greater than zero.

The toner particles are cooled and collected by the hopper 1
Assuming that a time required to pass through the heat treatment space 1 before being introduced into the heat treatment space 2 is a passing time P (s), P is defined by the following equation. P = X / V Here, in the above equation, X is a value obtained by cooling from the intersection M between the extension of the center line of the dispersion nozzle 3 and the extension of the inner wall of the hot air supply nozzle 8.
Opening 1 at end of collection hopper 12 on heat treatment space 1 side
The distance (m) to 2a and V are the flow velocity (m / s) of the hot air 2.

An outside air inlet 13 for introducing outside air as cooling air 11 is provided at the upper end of the cooling / collecting hopper 12. In this case, since the temperature of the production atmosphere is stably controlled, the outside air is directly introduced as the cooling air 11 from the outside air inlet 13, but the method of introducing the cooling air 11 is not particularly limited. is not. For example, FIG.
As shown in FIG. 4, a cooling air 11 stably controlled by a cool air chiller or the like is generated by a cooling air generator 14, and the cooling air 11 is cooled from a cooling air introduction jacket 15 provided above the cooling / collecting hopper 12. -It may be made to introduce into the collection hopper 12 in the state of a swirling flow or the like. As the cooling air generator 14, a commercially available cooling air control generator may be used, and if the installation location of the manufacturing apparatus is maintained at a constant temperature and humidity, a stable control apparatus is not particularly required.

The temperature of the cooling air 11 is preferably 35 ° C. or lower, and more preferably the temperature is stably controlled within this temperature range. With cooling air 11 at a temperature exceeding 35 ° C.,
Since the toner after the heat treatment cannot be sufficiently cooled, fusion between toner particles occurs, which causes fogging and the like when the electrophotographic toner is used, which is not preferable. Further, the temperature of the cooling air 11 is particularly preferably 10 ° C. or less. As a result, heat energy is applied only to the vicinity of the toner particle surface, and the surface of the toner particle is sufficiently cooled before heat is applied to the inside of the toner particle. For this reason, heat treatment at a higher temperature can be performed without causing fusion or aggregation of the toner particles. Therefore, it is possible to perform a smoothing process, fix modified fine particles or form a film while maintaining the shape of the toner particles in an irregular shape, and it is also possible to completely form the toner particles into a spherical shape. Becomes Therefore, it is possible to control the shape and state of the electrophotographic toner in a wider range. The temperature of the cooling air 11 is preferably as low as possible. However, at a temperature below the freezing point, 0 ° C. or more is appropriate because moisture in the introduced gas such as the hot air 2 and the cooling air 11 may cause freezing.

The hot air 2 and the cooling air 11 introduced
Is preferably stably controlled. Thereby, it is possible to stably produce an electrophotographic toner having a shape and a fixed or film-formed state which are constantly controlled irrespective of the surrounding environment, and it is possible to produce an electrophotographic toner having no variation among lots. If the temperatures of the hot air 2 and the cooling air 11 to be introduced are not stable, the shape and state of the manufactured electrophotographic toner vary, and depending on the surface condition of the electrophotographic toner, the charging performance of the electrophotographic toner and The flow state may change, which is not preferable.

The heat treatment and the cooling are preferably performed in a dry gas atmosphere. In particular, when the outside air in a humid period is introduced, moisture in the air may condense when the hot air 2 is cooled, which may cause aggregation of toner particles. By performing the heat treatment and cooling in a dry gas atmosphere, aggregation of toner particles due to dew moisture can be prevented. In order to perform the heat treatment in a dry gas atmosphere, a dry gas atmosphere may be formed in the heat treatment space 1 by using a dry gas as the hot air 2, the compressed gas, and the rectifying gas.
Further, in order to perform cooling in a dry gas atmosphere, the cooled dry gas is sent as cooling air 11 into the cooling / collecting hopper 12 to form a dry gas atmosphere in the cooling / collecting hopper 12.

As the dry gas, for example, dry air (dry air) or an inert gas can be used.
The dry air described above may be any air from which moisture has been removed, the pressure dew point under a predetermined pressure being equal to or lower than the temperature of the cooling air 11 when converted to the atmospheric pressure dew point. The dry air may be produced by removing moisture in the air using a commercially available device for removing moisture in the air, for example, SELEX DRY (trade name; manufactured by KK KK). Helium, argon, or the like can be used as the inert gas. As the dry gas, an inert gas is more preferable. As a result, a chemical change such as oxidation of a substance contained in the toner particles can be prevented, and an electrophotographic toner having stable characteristics such as no change in characteristics such as chargeability can be manufactured. In addition, when the toner particles are treated in the hot air 2 at high temperature, especially when an additive having a metal component is contained inside or on the surface of the toner particles, the function of the additive and the like does not decrease due to oxidation, and the additive is stable. An electrophotographic toner having charging performance and various imparting functions can be manufactured.

A collection box 16 for collecting heat-treated and cooled toner particles (toner for electrophotography) is connected to the lower end of the cooling / collecting hopper 12 via a pipe 17. The end of the pipe 17 opposite to the side connected to the collection box 16 is sealed here, but may be an inlet for introducing a rectifying gas for adjusting the flow of the processed toner particles.

In FIG. 1, the hot air 2 and the toner particles are supplied from above to below.
The hot air 2 and the toner particles may be supplied upward from below.

Next, a method for implementing the manufacturing method of the present invention using the manufacturing apparatus shown in FIGS. 1 and 2 or the manufacturing apparatus shown in FIGS. 3 and 4 will be described. First, hot air 2
Is sprayed from a hot air generator 7 disposed above the cooling / collecting hopper 12 through the hot air supply nozzle 8 toward the opening 12a of the cooling / collecting hopper 12.

Further, the toner particles are fed from the fixed amount supply device 5 and sent to each dispersion nozzle 3 through the pipe 4 by the compressed gas generated by the compressed gas generator 6. Sprayed towards 1.

When the toner particles sprayed from the dispersion nozzle 3 reach the intersection M of the heat treatment space 1, they are mixed and dispersed in the hot air 2 sent from the hot air supply nozzle 8. Then, the toner particles dispersed in the hot air 2 are cooled and collected by the hot air 2 generated by the hot air generator 7 and the rectifying gas introduced from the rectifying gas introduction port 9 from the intersection M of the heat treatment space 1. It is sent to 12 openings 12a. The toner particles are heat-treated and reformed by the thermal energy of the hot air 2 while traveling the distance X from the intersection M to the opening 12a.

The toner particles reaching the opening 12a of the cooling / collecting hopper 12
It is rapidly cooled by the cooling air 11. Then, the rapidly cooled toner particles are collected in a collection box 16 through a pipe 17.

The heat treatment and cooling conditions are such that the temperature of the electrophotographic toner collected after the heat treatment and cooling is at least that of the resin (binder resin or thermoplastic resin fine particles) forming the surface layer of the toner particles. It is preferable to set the temperature to be equal to or lower than the glass transition temperature (Tg).
That is, the temperature of the electrophotographic toner collected after the heat treatment and cooling, when using uniform toner particles,
The glass transition temperature of the binder resin of the toner particles is preferably equal to or lower than the glass transition temperature of the binder resin. Is preferred. As a result, an electrophotographic toner free from scattering and fogging can be manufactured. If the temperature of the electrophotographic toner collected after heat treatment and cooling exceeds at least the glass transition temperature (Tg) of the resin (binder resin or thermoplastic resin fine particles) forming the surface layer of the toner particles, the toner particles Problems such as scattering and fog due to agglomeration of the low-melting-point substances and leaching of the low-melting-point substance occur.

The heat treatment conditions and cooling conditions of the kneaded and pulverized toner particles having an irregular shape are adjusted so that the BET specific surface area value S of the obtained electrophotographic toner satisfies the following equation (1). Is preferred. 0.83 S ₀ ≧ S ≧ {3 / (md / 2)} (1) where S ₀ is the BET specific surface area value of the toner particles, m is the specific gravity of the electrophotographic toner, and d is the volume of the electrophotographic toner. Average particle size.

By producing an electrophotographic toner having a BET specific surface area value satisfying the formula (1) by the production method of the present invention, the surface of the particles is sufficiently smoothed to exhibit high fluidity, and An electrophotographic toner whose shape is controlled from an irregular shape to a spherical shape can be obtained without causing aggregation of toner particles. Further, the degree of smoothing or spheroidization can be quantitatively grasped, and the toner for electrophotography can be controlled and the production can be controlled according to the application.

Further, the heat treatment condition and the cooling condition of the toner particles when the mixed particles obtained by adding and mixing the modified fine particles to the kneaded and pulverized toner core particles having irregular shapes are used as the toner particles are obtained. It is preferable to adjust the BET specific surface area value S of the electrophotographic toner so as to satisfy the following expression (2). 0.65 Scalc. ≧ S ≧ {3 / (md / 2)} (2) Scalc. = S ₁ [100 / (100 + x)] + S ₂ [x
/ (100 + x)] where, Scalc. The BET specific surface area of the toner particles (mixed particles before the heat treatment), S ₁ is a BET specific surface area of the toner core particles, S ₂ is a BET specific surface area of the modified particulate, m Is the specific gravity of the electrophotographic toner, d is the volume average particle diameter of the electrophotographic toner, and x is the amount (parts by weight) of the modified fine particles added to 100 parts by weight of the toner core particles.

By producing a toner having a BET specific surface area value satisfying the formula (2) by the method of the present invention, the surface of the toner particles can be sufficiently smoothed, made spherical, the modified fine particles fixed or formed into a film. In addition, it is possible to obtain an electrophotographic toner in which the state of fixation or film formation that does not cause aggregation of toner particles is controlled. In addition, the state of fixation or film formation can be quantitatively grasped, and the toner for electrophotography can be controlled according to the application, and the production can be managed.

The bulk density of the electrophotographic toner is preferably at least 1.3 times the bulk density of the toner particles before the heat treatment. Thereby, especially when the mixed particles in which the modified fine particles are adhered to the surface of the toner core particles containing the binder resin are used as the toner particles, the toner has excellent fluidity, and the electrophotographic toner can be transferred to a developing device or a developing roller. Good replenishment followability when replenishing, high-print-rate originals (for example, solid monochrome originals)
Thus, it is possible to obtain an electrophotographic toner capable of forming a good image without causing blurring during continuous printing of.

As described above, in the method for producing an electrophotographic toner according to the present invention, after the toner particles are heat-treated using the heat treatment having the above-described structure, the toner particles are dispersed in hot air in a cooling vessel provided downstream of the heat treatment space. In the method for producing an electrophotographic toner for cooling the toner particles, the inner diameter D of the hot-air supply port is reduced.
Or the distance X from the heat treatment point T to the distance X from the heat treatment point T to the end of the cooling vessel on the heat treatment point T side is 0.6 or less, or the flow velocity of the hot air at the hot air supply port is 2.55 m / s.
The above is the method.

As a result, the toner for electrophotography can be collected in a sufficiently cooled state without causing aggregation due to thermal fusion or the like of the toner particles during the heat treatment. As a result, an electrophotographic toner that does not cause white fog or scattering of an image can be obtained.

Further, by enabling high-temperature processing while preventing aggregation and fusion of toner particles, and controlling the temperature and the like, it is possible not only to heat the inside of the toner particles but also to perform spheroidization, It is also possible to heat only the vicinity of the surface of the particles to smooth the surface of the toner particles while maintaining the irregular shape. As a result, it is possible to manufacture an electrophotographic toner controlled to have an arbitrary shape from an irregular shape to a spherical shape.

Further, in the case where the modified fine particles are adhered to the surface of the toner core particles to be fixed or formed into a film, similarly, the inner toner core particles are heated to form a complete film, whereby the spherical shape is obtained. Not only is it possible, but only the vicinity of the surfaces of the modified fine particles and the toner core particles can be heated, and the modified fine particles can be fixed or formed into a film while maintaining the irregular shape on the toner core particle surfaces. Therefore, also in this case, it is possible to manufacture an electrophotographic toner controlled to an arbitrary shape from an irregular shape to a spherical shape.

In addition, the applicant's Japanese Patent Application No. 9-19 / 1997 has been disclosed.
It is possible to make the toner particles spherical, which could not be achieved by the production method described in the specification of JP-A-7590, and to control the toner state in a wider range.

As described above, in order to obtain an electrophotographic toner having an arbitrary shape or an immobilized or film-formed state, sufficient thermal energy is required to cause the toner particles to change shape (or change state). To the toner particles, supplying cooling air at the moment when the desired particle state is reached immediately after the toner particles are dispersed in the heat treatment space, and further causing the heat-treated toner particles to undergo further shape change (or state). It is necessary to sufficiently cool to a temperature at which no change occurs.

Therefore, as described above, the temperature of the hot air is preferably in the range of 150 ° C. to 500 ° C., and the residence time of the toner particles to be heat-treated in the heat treatment space is 0.1 mm.
Preferably, the cooling air temperature is 35 ° C. or less.
The following is preferred. Further, it is preferable that both the hot air and the cooling air are stably controlled.

By manufacturing the electrophotographic toner under the above heat treatment conditions and cooling conditions, seepage of the low-melting substance contained in the toner particles, fusion and aggregation of the toner particles are prevented, and scattering and fog are prevented. It is possible to manufacture an electrophotographic toner that does not cause the electrophotography. In addition, regardless of the surrounding environment, it is possible to manufacture an electrophotographic toner having a stable shape and a fixed or film-formed state, which is constantly controlled without variation among lots.

Further, by controlling the temperature of the hot air within the range of 150 ° C. to 500 ° C., the toner for electrophotography having various states and functions of any shape from amorphous to spherical depending on the application. Can be obtained. For example, as an electrophotographic toner suitable for an image forming apparatus having a cleaning mechanism, it is possible to manufacture an electrophotographic toner having high fluidity and causing no cleaning failure by smoothing the surface of toner particles while maintaining an irregular shape. it can. Further, as an electrophotographic toner suitable for a cleaner-less image forming apparatus often seen in recent years, toner particles are completely spherical,
An electrophotographic toner having various functions such as high image quality, high fluidity, and high transferability can be manufactured. further,
Similarly, in the case of producing a color toner, a color toner for electrophotography having good color development and high image quality can be obtained.

In the production method of the present invention, when the surface treatment with the modified fine particles having various functions is performed on the toner core particles, the thermoplastic resin fine particles are used as the modified fine particles. Further, the advantage is obtained that the electrophotographic toner in a fixed or film-formed state without peeling or detachment can be obtained by heat fusion between the toner core particles and the thermoplastic resin fine particles.

Further, as described above, by selecting the composition, glass transition temperature, volume resistance value, molecular weight, etc. of the thermoplastic resin fine particles forming the outer shell of the electrophotographic toner, high-temperature storage stability is excellent. It is possible to manufacture an electrophotographic toner and an electrophotographic toner having significantly improved stress resistance.

[0099]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto.

Example 1 First, the glass transition temperature was 50
100 ° C. of styrene- (meth) acrylate copolymer (binder resin) at 6 ° C., 6 parts by weight of carbon black (coloring agent), 1 part by weight of a negatively chargeable charge control agent, and low molecular weight polypropylene (offset preventing agent) ) 3 parts by weight were mixed with a Henschel mixer and melt-kneaded at a temperature of 150 ° C using a twin-screw extruder. After cooling the obtained kneaded material, it was roughly pulverized using a feather mill, and further pulverized and classified with a jet mill pulverizer. Thus, amorphous toner particles having a volume average particle diameter of 10.5 μm and a BET specific surface area value of 1.85 m ² / g (hereinafter, referred to as toner TR1) were obtained. The specific gravity of the toner TR1 was 1.1 × 10 ⁶ kg / m ³ .

Using the manufacturing apparatus shown in FIGS. 3 and 4, according to the manufacturing method described in the embodiment of the invention, the toner TR1 is subjected to heat treatment and cooling for making the surface smooth or spherical, and cooling the toner TR1. A photographic toner (hereinafter simply referred to as toner) was manufactured.

Temperature of hot air 2 (hereinafter referred to as hot air temperature)
Was stably controlled at 300 ° C. As the hot air generator 7, a hot air flow surface reformer (trade name "Safusing System", manufactured by Nippon Pneumatic Industries Ltd.) was used. The temperature of the cooling air 11 (hereinafter referred to as cooling air temperature)
2 m for stably controlling the temperature to 10 ° C. by the cooling air generator 14 and introducing rectified gas to the upper part around the hot air supply nozzle 8.
The gap of m was provided as the straightening gas inlet 9. Dry air having an atmospheric dew point of 0 ° C. or less under a pressure of 8 kgf / cm ² was used as each of the introduced gases (hot air 2, rectifying gas, cooling air 11, and compressed gas) used in the heat treatment.

The flow rate F of the hot air 2 is set to 0.015 m ³ /
s, the inner diameter D of the hot air supply nozzle 8 (hereinafter, the nozzle diameter D
) To 0.05 m, the cross-sectional area A of the hot air supply nozzle 8
(Hereinafter referred to as the nozzle opening area A) is 1.963 × 10 ^−3.
m ² , the distance X from the intersection M between the extension of the center line of the dispersion nozzle 3 and the extension of the inner wall of the hot air supply nozzle 8 to the opening 12 a at the end of the cooling / collecting hopper 12 on the heat treatment space 1 side is set to 0. .03 m.

[Examples 2 to 7] Using the toner TR1 prepared in Example 1, the hot air temperature was set to 100 ° C., 150 ° C., and 20 ° C.
A toner was manufactured in the same manner as in Example 1 except that the temperature was changed to 0 ° C., 400 ° C., 500 ° C., and 550 ° C., respectively.

The toner TR1 (shown as TR1 in the table) and each of the toners obtained in Examples 1 to 7 were evaluated by the following methods. First, for the obtained toner, the bulk density of the toner was measured using a bulk density measuring device (JIS K 5101). Further, using a BET specific surface area measuring device (trade name “Gemini 2360”, manufactured by Shimadzu Corporation), the BE of the toner is measured by a one-point measuring method.
The T specific surface area value (referred to as specific surface area in the table) was measured.
In addition, Multisizer II (trade name, manufactured by Coulter)
Was used to measure the volume average particle size of the toner.

The shape of the toner was confirmed by observation with a scanning electron microscope (SEM). The irregular shape was “1”, the smooth surface, the irregular shape with rounded corners was “2”, and the surface was smooth. The spherical shape was evaluated as “3” and the spherical shape having a non-smooth surface as “4”.

Further, as an actual photograph evaluation, 0.3 parts by weight of silica and 0.2 parts of magnetite were
About one-component developer obtained by externally adding and mixing parts by weight,
Printer manufactured by Sharp Corporation (trade name “JX923
0 ") to make a continuous black-and-white original document
The black solid followability was evaluated on a three-point scale of “◎” (extremely good), “○” (good), and “×” (poor).

As an actual image evaluation, a two-component developer obtained by mixing the above-mentioned one-component developer with a ferrite carrier at a ratio of 4% by weight was used for a copying machine manufactured by Sharp Corporation (trade name “AR5030”). Was used to continuously print 10,000 sheets, and the image quality and fog were evaluated on three scales of “◎” (extremely good), “○” (good), and “×” (poor).

Table 1 summarizes the production conditions and evaluation results of toner TR1 (denoted by TR1 in the table) and Examples 1 to 7.

[0110]

[Table 1]

From the results of Examples 1 to 7, the hot air temperature was 1
It turns out that the range of 50 ° C-500 ° C is preferred.

Further, the production conditions in which the BET specific surface area value S calculated from the volume average particle diameter of the obtained toner and the physical property values of the toner particles satisfy the above-described formula (1), for example, the production conditions (Example 6) d = 10.7, the left side of the above equation (1) is 0.83 S ₀ = 1.535, S = 0.51, and the right side of the equation (1) is 3 / (md / 2) = 0.500. (Satisfies (1)), it can be seen that black solid followability in one-component development is improved.

Further, it can be seen that, under the manufacturing conditions in which the bulk density of the obtained toner is at least 1.3 times the bulk density of the toner particles, the black solid followability in one-component development is improved.

[Embodiment 8] Toner T prepared in Embodiment 1
Using R1, a toner was manufactured in the same manner as in Example 1 except that the flow rate F was changed to 0.010 m ³ / s and the distance X was changed to 0.005 m.

[Embodiment 9] Toner T prepared in Embodiment 1
A toner was manufactured in the same manner as in Example 1 except that the flow rate F was changed to 0.010 m ³ / s using R1.

[Comparative Example 1] Toner T prepared in Example 1
A toner was manufactured in the same manner as in Example 1 except that the flow rate F was changed to 0.010 m ³ / s and the distance X was changed to 0.04 m using R1.

For each of the toners obtained in Examples 8 and 9 and Comparative Example 1, the BET specific surface area was measured in the same manner as in Examples 1 to 7, and the aggregation of the toner particles was determined by observation with a scanning electron microscope. The presence or absence was confirmed, and the case where there was no aggregation was evaluated as “○”, and the case where there was aggregation was evaluated as “×”. Table 2 summarizes the manufacturing conditions and evaluation results of Examples 8 and 9 and Comparative Example 1.

[0118]

[Table 2]

From the results of Examples 8 and 9 and Comparative Example 1,
It is understood that the ratio X / D between the distance X and the nozzle diameter D is preferably 0.6 or less.

Example 10 A toner was manufactured in the same manner as in Example 1 except that the flow rate F was changed to 0.005 m ³ / s using the toner TR1 prepared in Example 1.

[Comparative Example 2] Toner T prepared in Example 1
A toner was manufactured in the same manner as in Example 1 except that the flow rate F was changed to 0.003 m ³ / s using R1.

For each of the toners obtained in Examples 1, 9, and 10 and Comparative Example 2, the BET specific surface area was measured in the same manner as in Examples 1 to 7, and the toner particles were observed with a scanning electron microscope. The presence or absence of agglomeration was confirmed, and the case where there was no aggregation was evaluated as “「 ”, and the case where there was aggregation was evaluated as“ × ”. Table 3 summarizes the manufacturing conditions and evaluation results of Examples 1, 9, and 10 and Comparative Example 2.

[0123]

[Table 3]

From the results of Examples 1, 9, and 10 and Comparative Example 2, it is understood that the flow velocity V of the hot air 2 is preferably 2.55 m / s or more. Further, from the results of Examples 1.8 to 10 and Comparative Examples 1.2, the passage time P of the toner particles in the heat treatment space 1 is more preferably 12 ms (0.012 seconds) or less, and 6 ms (0.006 seconds). It can be seen that the following is more preferable.

[Examples 11 to 16] Using the toner TR1 prepared in Example 1, the hot air temperature and the cooling air temperature were set in Table 4 below.
A toner was manufactured in the same manner as in Example 1 except that the toner was variously changed as shown in FIG.

Example 17 100 parts by weight of the toner TR1 as the toner core particles (hereinafter referred to as core particles in the table) prepared in Example 1 were modified fine particles having an average particle diameter of 0.15 μm. Styrene having a glass transition temperature of 72 ° C.
Mixed particles were obtained by adding 5 parts by weight of methyl methacrylate copolymer fine particles and mixing with a Henschel mixer for 10 minutes. A hot air temperature of 2
Heat treatment and cooling were performed under the same conditions as in Example 1 except that the temperature was changed to 00 ° C. and the cooling air temperature was changed to 35 ° C., to obtain a toner.

For each of the toners obtained in Examples 11 to 17, measurement of the temperature (hereinafter simply referred to as temperature in the table) collected in the collection box 16 and evaluation of the aggregation state by a scanning electron microscope were performed. Was. Aggregation state was evaluated by observation with a scanning electron microscope as follows: “A” when no agglomeration occurred, “A” when there was some agglomeration but at a level that was practically acceptable, The case where there was a problem was evaluated as “×”.

The production conditions and evaluation results of Examples 1 and 11 to 17 are summarized in Table 4.

[0129]

[Table 4]

The results of Examples 1-11 to 17 indicate that when heat treatment is performed at a high temperature, the cooling air temperature is preferably 10 ° C. or less. In addition, it can be seen that when the recovery temperature of the obtained toner is equal to or lower than the glass transition temperature of the binder resin in the toner core particles or equal to or lower than the glass transition temperature of the modified fine particles, no aggregation occurs, which is preferable.

[Embodiment 18] Instead of the heat treatment apparatus 10, a heat treatment apparatus in which the rectifying gas introduction port 9 is not provided around the hot air supply nozzle 8 and hermetically closed (hereinafter referred to as a closed heat treatment apparatus)
The same heat treatment and cooling as in Example 1 were performed except for using, to obtain a toner. Example 8
10 to 10. In the same manner as in Comparative Example 1, measurement of the BET specific surface area value (referred to as specific surface area in the table) and evaluation of the presence or absence of aggregation by scanning electron microscope observation were performed. The state of the obtained toner and the BET specific surface area value were almost the same as those in Example 1.

Further, the state of contamination around the heat treatment space 1 in the heat treatment apparatus 10 and the closed heat treatment apparatus was observed.
As in the first embodiment, a 2 mm rectifying gas inlet 9 that allows a small amount of rectifying gas to flow in from the outer peripheral portion of the hot air supply nozzle 8.
When the heat treatment was performed in the heat treatment device 10 provided with the toner, the supplied toner particles flowed smoothly to the cooling / collecting hopper 12 without staying in the upper portion of the device. On the other hand, when heat treatment was similarly performed in a closed heat treatment device in which the upper portion of the hot air supply nozzle 8 was closed as in Example 18, a vortex was generated at the junction of the hot air 2 and the cooling air 11, and a small amount of toner particles was generated. A phenomenon of flowing to the upper portion of the hot air supply nozzle 8 and fusing was observed.

Table 5 shows the manufacturing conditions and evaluation results of Examples 1 and 18.

[0134]

[Table 5]

Examples 19 to 21 First, 100 parts by weight of a styrene- (meth) acrylate copolymer having a glass transition temperature of 55 ° C., 6 parts by weight of carbon black, and 3 parts by weight of low-molecular polypropylene were mixed with a Henschel mixer. And melt-kneaded at a temperature of 150 ° C. using a twin-screw extruder. After cooling the obtained kneaded material, it was roughly pulverized using a feather mill, and further pulverized and classified with a jet mill pulverizer. Thereby, the volume average particle size becomes 1
Amorphous toner particles having a BET specific surface area of 0.5 μm and a BET specific surface area of 1.70 m ² / g (hereinafter, referred to as toner TR2) were obtained. The specific gravity of the toner TR2 is 1.1 × 10 ⁶ kg.
/ M ³ .

With respect to 100 parts by weight of toner TR2 as toner core particles containing no charge controlling agent prepared above,
As modified fine particles, 5 parts by weight of a copolymer of methyl methacrylate-butyl methacrylate-styrene-zinc methacrylate (in which the methyl group of methyl methacrylate is replaced with zinc) is added, and mixed with a Henschel mixer for 10 minutes. As a result, mixed particles were obtained.

The gas (hot air 2, compressed gas, rectifying gas, and cooling air 11) introduced into the heat treatment space 1 and the cooling / collecting hopper 12 with respect to the mixed particles is
Using outside air, dry air having an atmospheric pressure dew point of 0 ° C. or less under a pressure of 8 kgf / cm ² , and helium gas,
A toner was obtained by performing heat treatment and cooling under the same conditions as in Example 1 except that the hot air temperature was changed to 400 ° C. and the cooling air temperature was changed to 25 ° C., respectively.

For each of the toners obtained in Examples 19 to 21, the volume average particle diameter was measured in the same manner as in Examples 1 to 7, and the charge amount of the ball mill was measured. The charge amount of a two-component developer obtained by mixing the above toner with a ferrite carrier at a ratio of 4% by weight and mixing at a stirring speed of 60 rpm for 30 minutes under an environment of 25 ° C./50 Rh% is used. Was measured using a blow-off charge meter. Table 6 summarizes the production conditions and evaluation results of Examples 19 to 21.

[0139]

[Table 6]

According to the results of Examples 19 to 21, when the outside air was introduced, the volume average particle diameter was slightly increased and some agglomerated particles were observed, whereas when dry air and helium gas were used. It can be seen from FIG. 2 that the charge amount is large and good.

[Examples 22 to 26] With respect to 100 parts by weight of toner TR1 as the toner core particles prepared in Example 1, modified fine particles had an average particle diameter of 0.15 µm, a glass transition temperature of 72 ° C, and a BET ratio. After adding 5 parts by weight of styrene-methyl methacrylate copolymer fine particles having a surface area value of 37.8 m ² / g, mixed particles were obtained by mixing with a Henschel mixer for 10 minutes. The mixed particles were subjected to the same heat treatment and cooling as in Example 1 except that the hot air temperature was changed as shown in Table 7, to obtain a toner.

As the hot air generator 7, a hot air flow surface reforming device (trade name "Safusing System", manufactured by Nippon Pneumatic Industries Ltd.) was used. The cooling air 11 was stably controlled at 10 ° C. by the cooling air generator 14, and a 2 mm gap for introducing the rectifying gas was provided as the rectifying gas inlet 9 around the hot air supply nozzle 8. In addition, each introduced gas (hot air 2, rectifying gas, cooling air 1) used during the heat treatment was used.
1, and compressed gas) were all dry air having an atmospheric dew point of 0 ° C. or less under a pressure of 8 kgf / cm ² .

Example 27 The mixed particles subjected to the same pre-mixing as in Examples 22 to 26 were subjected to a mechanical impact type surface modification device (trade name “Hybridization System”, manufactured by Nara Machinery Co., Ltd.). After the modification, a toner was obtained.

The same evaluation as in Examples 1 to 7 was performed for each of the toners obtained in Examples 22 to 27. That is, first, the bulk density and the BET specific surface area value (referred to as specific surface area in the table) of the obtained toner were measured in the same manner as in Examples 1 to 7. The volume average particle diameter of the toner was measured using a master sizer (trade name, manufactured by Malvern Instruments Co., Ltd.).

The shape of the toner was confirmed by observation with a scanning electron microscope. The irregular shape was “1”, the irregular shape having a smooth surface and rounded corners was “2”, and the spherical shape was smooth. The shape of the toner was evaluated as “3”, and the spherical shape having a non-smooth surface as “4”.

Further, as an actual photograph evaluation, 0.3 parts by weight of silica and 0.2 parts by weight of magnetite were
About one-component developer obtained by externally adding and mixing parts by weight,
Printer manufactured by Sharp Corporation (trade name “JX923
0 ") to make a continuous black-and-white original document
The black solid followability was evaluated on a three-point scale of “◎” (extremely good), “○” (good), and “×” (poor).

As an actual image evaluation, a two-component developer obtained by mixing the above one-component developer with a ferrite carrier at a ratio of 4% by weight was used for a copying machine manufactured by Sharp Corporation (trade name “AR5030”). Was used to continuously print 10,000 sheets, and the image quality and fog were evaluated on three scales of “◎” (extremely good), “○” (good), and “×” (poor).

Table 7 summarizes the manufacturing conditions and evaluation results of Examples 22 to 27.

[0149]

[Table 7]

The results of Examples 22 to 27 show that the hot air temperature is preferably in the range of 150 ° C. to 500 ° C.
In addition, the BET specific surface area calculated from the volume average particle diameter of the toner and the physical property values of the toner core particles and the modified fine particles satisfies the above-mentioned formula (2).
(D = 10.9, Scalc. = 3.56, 0.65 Scalc. = 2.32 on the left side of the above equation (2), S =
0.50, 3 / (md / 2) = 0.50 on the right side of equation (2)
0, which satisfies the expression (2)), it can be seen that the black solid followability in one-component development is good.

Example 28 100 parts by weight of toner TR2 (glass transition temperature of 55 ° C.) as the toner core particles were used as modified fine particles, each having a glass transition temperature of 72.
After adding 5 parts by weight of polymethyl methacrylate fine particles adjusted to an average particle size of 0.15 μm at 0 ° C., the mixture was mixed with a Henschel mixer for 10 minutes to obtain mixed particles.

Using the production apparatus shown in FIGS. 1 and 2, a hot air flow surface reforming apparatus (trade name “Safusing System”, manufactured by Nippon Pneumatic Industries, Ltd.) was used as the hot air generator 7 for the mixed particles. Use hot air temperature 300
Heat treatment was performed at ℃. Further, cooling was performed by introducing 25 ° C. outside air that was stably controlled as the cooling air 11. Thus, a toner was obtained. In addition, each introduced gas used during heat treatment (hot air 2, compressed gas, and rectified gas)
Have an atmospheric dew point of 0 kg under 8 kgf / cm ² pressure.
Dry air below ℃ was used.

[Examples 29 to 32] The toner TR in Examples 19 to 21 except that only the glass transition temperature of the binder resin was changed from 35 ° C to 75 ° C shown in Table 8
In the same manner as in the preparation method of No. 2, four kinds of average particle diameters of 10.5 μm
Was prepared. Created toner core particles 10
After adding 5 parts by weight of polymethyl methacrylate fine particles adjusted to an average particle size of 0.15 μm at a glass transition temperature of 72 ° C. as modified fine particles to 0 parts by weight,
Mixed particles were obtained by mixing with a Henschel mixer for 10 minutes. The mixed particles were subjected to the same heat treatment and cooling as in Example 28 to obtain a toner.

[Examples 33 to 36] To 100 parts by weight of toner TR2 (glass transition temperature of 55 ° C) as toner core particles, modified fine particles were added at a temperature of 55 ° C to 10
After adding 5 parts by weight of polymethyl methacrylate fine particles having a glass transition temperature of 8 ° C. and adjusted to an average particle size of 0.15 μm, mixed particles were obtained by mixing with a Henschel mixer for 10 minutes. The mixed particles were subjected to the same heat treatment and cooling as in Example 28 to obtain a toner.

Toner 100 obtained in Examples 28 to 36
0.3 part by weight of silica and 0.2 part by weight of magnetite are added and mixed externally to obtain a one-component developer, and the one-component developer is further added to a ferrite carrier at a ratio of 4% by weight. To obtain a two-component developer. Then, as a live-action evaluation, a copying machine manufactured by Sharp Corporation (trade name “SF20
27 "), and the presence or absence of fogging and filming was evaluated as" ○ "(no)," △ "(there is no practical problem)," x "(practical) (To the extent that problems occur).

The evaluation of the fixability of the toners obtained in Examples 28 to 36 was performed by a rubbing test (1 kg load) with a sand eraser (trade name “ER-502K”, manufactured by Lion Corporation) using a friction fastness tester. ) Was carried out, and the determination was made based on the rubbing residual ratio. Here, it is assumed that a rubbing residual ratio of 80% or more is a level having no practical problem.

The evaluation of the storage stability of the toners obtained in Examples 28 to 36 was carried out by using the above-described copying machine (trade name “SF202”).
7 "), put 320g in the toner cartridge,
The test was performed by judging the presence or absence of blocking after standing for 2 weeks.

The evaluation of the fixing property and the preservability was evaluated as “O” (good), “Δ” (practical limit level), and “X” (poor).
The evaluation was graded. Table 8 summarizes the production conditions and evaluation results of Examples 28 to 36.

[0159]

[Table 8]

[Examples 37 to 40] With respect to 100 parts by weight of the toner TR2 as the toner core particles prepared in Examples 19 to 21, the volume average particle diameter as a modified fine particle was from 0.1 μm shown in Table 9. After adding 5 parts by weight of polymethyl methacrylate fine particles adjusted to a value of 2 μm, the mixture was mixed for 10 minutes with a Henschel mixer to obtain mixed particles. The mixed particles were subjected to heat treatment and cooling under the same conditions as in Example 28 to obtain a toner.

As in Examples 28 to 36, Examples 37 to
40 with respect to 100 parts by weight of the toner obtained in Step No. 40.
3 parts by weight and 0.2 part by weight of magnetite are externally added and mixed to obtain a one-component developer, and then the one-component developer is mixed with a ferrite carrier at a ratio of 4% by weight to obtain a two-component developer. Agent was obtained. Then, as a real-photo evaluation, the above two-component developer was subjected to continuous real-photo shooting of 10,000 sheets using a copying machine manufactured by Sharp Corporation (trade name “SF2027”), and the presence or absence of fog and filming was evaluated as “O” ( None), “△” (present to the extent that no practical problem occurs), “X” (present to the extent that practical problem occurs)
It was evaluated on a scale. Table 9 summarizes the manufacturing conditions and evaluation results of Examples 37 to 40.

[0162]

[Table 9]

Examples 41 to 44 100 parts by weight of the toner TR2 as the toner core particles prepared in Examples 19 to 21 were used as modified fine particles with a glass transition temperature of 72 ° C.
Each of the polymethyl methacrylates adjusted to an average particle size of 0.15 μm by 0.1 to 20 parts by weight shown in Table 10
After adding in an amount of up to parts by weight, the mixture was mixed for 10 minutes with a Henschel mixer to obtain mixed particles. The mixed particles were subjected to heat treatment and cooling under the same conditions as in Example 28 to obtain a toner.

In the same manner as in Examples 28 to 36, Examples 41 to
44 with respect to 100 parts by weight of the toner obtained in Step No. 44.
3 parts by weight and 0.2 part by weight of magnetite are externally added and mixed to obtain a one-component developer, and then the one-component developer is mixed with a ferrite carrier at a ratio of 4% by weight to obtain a two-component developer. Agent was obtained. Then, as a real-photo evaluation, the above two-component developer was subjected to continuous real-photo shooting of 10,000 sheets using a copying machine manufactured by Sharp Corporation (trade name “SF2027”), and the presence or absence of fog and filming was evaluated as “O” ( None), “△” (present to the extent that no practical problem occurs), “X” (present to the extent that practical problem occurs)
It was evaluated on a scale. Table 10 summarizes the manufacturing conditions and evaluation results of Examples 41 to 44.

[0165]

[Table 10]

Examples 45 to 47 As shown in Table 11, styrene- (meth) acrylate copolymers (St / Ac in the table) and polyester resins (Pes in the table) were used as binder resins. ), Respectively, in the same manner as in Examples 19 to 21.
1.5 μm particles were prepared and used as toner core particles. Further, as modified fine particles, polymethyl methacrylate (described as PMMA in the table) having a solubility parameter value (described as SP value in the table) shown in Table 11 and having a volume average particle diameter of 0.4 μm, and styrene- Fine particles of a butyl methacrylate copolymer (denoted as St / BMA in the table) were used.

After 5 parts by weight of the modified fine particles were added to the surface of the toner core particles, they were mixed for 10 minutes using a Henschel mixer. As a result, mixed particles were obtained. The mixed particles were subjected to heat treatment and cooling under the same conditions as in Example 28 to obtain a toner.

In the same manner as in Examples 28 to 36, Examples 45 to
47 with respect to 100 parts by weight of the toner obtained in Step No. 47.
3 parts by weight and 0.2 part by weight of magnetite are externally added and mixed to obtain a one-component developer, and then the one-component developer is mixed with a ferrite carrier at a ratio of 4% by weight to obtain a two-component developer. Agent was obtained. Then, as a real-photo evaluation, the above two-component developer was subjected to continuous real-photo shooting of 10,000 sheets using a copying machine manufactured by Sharp Corporation (trade name “SF2027”), and the presence or absence of fog and filming was evaluated as “O” ( None), “△” (present to the extent that no practical problem occurs), “X” (present to the extent that practical problem occurs)
It was evaluated on a scale. Table 11 summarizes the production conditions and evaluation results of Examples 45 to 47.

[0169]

[Table 11]

[Examples 48 to 52] With respect to 100 parts by weight of the toner TR2 as the toner core particles prepared in Examples 19 to 21, the modified fine particles were adjusted to have various volume resistance values shown in Table 12. After adding 5 parts by weight of the adjusted methyl methacrylate-butyl methacrylate copolymer fine particles, they were mixed for 10 minutes using a Henschel mixer. As a result, mixed particles were obtained. The mixed particles were subjected to a heat treatment under the same conditions as in Example 1 to obtain a toner.

The volume resistance values of the toner core particles and the modified fine particles were measured using a dielectric loss measuring device (manufactured by Ando Electric Co., Ltd.). The toner TR used as the toner core particles
The volume resistance value of No. 2 was 3 × 10 ¹¹ Ω · cm.

Toner 100 obtained in Examples 48 to 52
After externally mixing 0.3 parts by weight of silica and 0.2 parts by weight of magnetite with respect to parts by weight to obtain a one-component developer, the one-component developer was further added to a ferrite carrier at a ratio of 4% by weight. To obtain a two-component developer. Then, as a live-action evaluation, a copying machine manufactured by Sharp Corporation (trade name “AR50
30)), the presence / absence of transfer failure of the initial image is indicated by “○” (no transfer failure) and “X” (transfer failure)
, And the transfer efficiency after 10,000 real copies were taken was measured. Table 12 summarizes the production conditions and evaluation results of Examples 48 to 52.

[0173]

[Table 12]

[Examples 53 to 58] With respect to 100 parts by weight of the toner TR2 as the toner core particles prepared in Examples 19 to 21, the modified fine particles had an average particle diameter of 0.15 µm.
After adding 5 parts by weight of each of the six types of polymer fine particles shown in Table 13 adjusted as described above, mixing was performed for 10 minutes with a Henschel mixer to obtain mixed particles.

The above-mentioned six kinds of polymer fine particles include polymethyl methacrylate fine particles (denoted as PMMA in the table), methyl methacrylate-butyl methacrylate copolymer fine particles (denoted as MMA / BMA in the table), and methyl methacrylate-butyl. Methacrylate-fluorine monomer copolymer fine particles (methyl methacrylate and butyl methacrylate mixed with 10% by weight of a fluorine monomer and copolymerized. In the table, MMA / BMA / F10%
), Methyl methacrylate-butyl methacrylate-styrene-methacrylic acid copolymer fine particles (denoted as MMA / BMA / St / MAA in the table), and methyl methacrylate-butyl methacrylate-styrene-methacrylic acid copolymer fine particles with water. Washed (MM in the table)
A / BMA / St / MAA washed product) and fine particles of methyl methacrylate-butyl methacrylate-styrene-zinc methacrylate (MMA / BMA /
St / MAA-Zn). In addition, zinc methacrylate is obtained by substituting the methyl group of methyl methacrylate with zinc.

The mixed particles were subjected to a heat treatment under the same conditions as in Example 1 by using a hot air flow surface reforming device (trade name “Safusing System”, manufactured by Nippon Pneumatic Industries, Ltd.) as the hot air generator 7. Was performed to obtain a toner.

For measuring the charge amount of the toners obtained in Examples 53 to 58, the toner was added to a ferrite carrier at 4% by weight.
And a stirring speed of 60 r using a ball mill.
A two-component developer obtained by mixing at pm for 30 minutes was used. The charge amount of the two-component developer at normal temperature and normal humidity (20 ° C./60%, indicated as N / N in the table) and high temperature and high humidity (35 ° C./85%, H / H in the table)
In the following) was measured using a blow-off charge amount measuring device.

Further, with respect to 100 parts by weight of the toners obtained in Examples 53 to 58, 0.2 part by weight of silica and 0.3 part by weight of magnetite were externally added and mixed to obtain a one-component developer. Then, as a real-image evaluation by one-component development, evaluation of image quality and fog of an initial image using a printer (trade name “JX9223”) of the one-component developer, and charging by a blow-off charge amount measuring device. The amount was measured. The evaluation of image quality and fogging was evaluated as “○” (good), “△” (practical limit level),
"X" (poor) was evaluated on a three-point scale.

Table 13 summarizes the production conditions and evaluation results of Examples 53 to 58.

[0180]

[Table 13]

[Examples 59 to 61] Volume average particle size 9.5
0.3 parts of silica fine particles (trade name “R972”, manufactured by Nippon Aerosil Co., Ltd.) are externally added as modified fine particles to the μm toner core particles to obtain mixed particles (hereinafter referred to as untreated particles). Was.

The manufacturing apparatus shown in FIGS. 3 and 4 was used in which the number of dispersion nozzles 3 was set to 2, 4, and 8, respectively, with respect to untreated particles as toner particles. The toner was manufactured by the manufacturing method described in the section of the first embodiment. The toner production conditions were a hot air temperature of 350 ° C., a cooling air temperature of 10 ° C., and a processing amount of 2 kg / h.

The particle size distribution of the toners obtained in Examples 59 to 61 was measured using Multisizer II (trade name, manufactured by Coulter, Inc.).
And the ratio of particles having a volume average particle size of 15 μm or more was determined. Table 14 shows the production conditions and evaluation results of Examples 59 to 61 together with the evaluation results of the untreated particles.

[0184]

[Table 14]

[0185]

As described above, the method for producing an electrophotographic toner according to claim 1 of the present invention provides a heat treatment space in which toner particles containing a binder resin are heat-treated, and a hot air supply in which hot air flows into the heat treatment space. After heat-treating the toner particles using a heat-treating device having a mouth and a toner-particle supply port that supplies the heat-treated space so as to disperse the toner particles in hot air,
A method for producing an electrophotographic toner in which said toner particles dispersed in hot air are cooled in a cooling container provided downstream of a heat treatment space, comprising: an inner diameter D of a hot air supply port, and a center line of the toner particle supply port. Is set so that X / D ≦ 0.6 from the intersection of the extension line of the above with the extension surface of the inner wall of the hot air supply port to the end of the cooling vessel on the heat treatment space side.

According to the above method, the toner particles can be uniformly dispersed in the hot air, the aggregation of the toner particles can be prevented, and the modified fine particles can be prevented from maintaining the irregular shape with respect to the irregular toner core particles. By fixing the toner and smoothing the surface of the toner particles, the toner for electrophotography can be controlled to have an arbitrary shape.

As described above, the method for producing an electrophotographic toner according to claim 2 of the present invention comprises a heat treatment space in which toner particles containing a binder resin are heat treated, a hot air supply port through which hot air flows into the heat treatment space, and Heat treating the toner particles using a heat treatment apparatus having a toner particle supply port for supplying the toner particles to the heat treatment space so as to disperse the toner particles in the hot air, and then heating the toner particles in a cooling vessel provided on the downstream side of the heat treatment space. A method for producing an electrophotographic toner, wherein the toner particles dispersed therein are cooled, wherein the flow rate of hot air in a hot air supply port is set to 2.5.
This is a method of controlling to 5 m / s or more.

According to the above method, the toner particles can be uniformly dispersed in the hot air, the aggregation of the toner particles can be prevented, and the modified fine particles in the state where the amorphous toner core particles are maintained in the irregular shape are maintained. By fixing the toner and smoothing the surface of the toner particles, the toner for electrophotography can be controlled to have an arbitrary shape.

The method for producing an electrophotographic toner according to claim 3 of the present invention is a method in which the number of toner particle supply ports is four or more as described above.

According to the above method, it is possible to significantly suppress the occurrence of collision and aggregation between toner particles and pulverization of the toner particles, and it is possible to greatly improve the processing capacity by increasing the supply amount of the toner particles. This has the effect.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a toner for electrophotography according to the fourth aspect, wherein the heat treatment apparatus introduces a rectifying gas inlet for introducing a rectifying gas for adjusting the flow of toner particles in the heat treatment space. The method further comprises:

According to the above-described method, it is possible to suppress the generation of a vortex at or around the hot air supply port, and to prevent toner particles from adhering to the inner wall of the apparatus surrounding the heat treatment space or the hot air supply port. As a result, when the type of the electrophotographic toner to be manufactured is switched, it is possible to prevent the electrophotographic toner from being contaminated by a residue or a fusion product of the toner particles used before.

The method for producing an electrophotographic toner according to claim 5 of the present invention is a method of performing heat treatment and cooling in a dry gas atmosphere as described above.

According to the above method, the heat treatment and cooling can be prevented from being affected by the temperature and humidity, so that the heat efficiency can be improved and the heat treatment with low energy can be performed.
This has the effect of preventing condensation during cooling and preventing aggregation of the collected electrophotographic toner.

In the method for producing an electrophotographic toner according to the sixth aspect of the present invention, as described above, mixed particles obtained by adhering modified fine particles to the surface of toner core particles containing a binder resin are used as toner particles. Is the way.

According to the above method, the surface of the toner core particles containing the binder resin is modified with the modified fine particles to produce a surface-modified electrophotographic toner having an arbitrary shape from an irregular shape to a spherical shape. It has the effect of being able to do so.

The method for producing an electrophotographic toner according to claim 7, wherein the modified fine particles have a higher glass transition temperature than the glass transition temperature of the toner core particles. This is the method.

According to the above-mentioned method, there is an effect that an electrophotographic toner which is excellent in storage stability and in which the modified fine particles are not separated or separated can be obtained.

The method for producing an electrophotographic toner according to claim 8 of the present invention is a method as described above, wherein the volume resistivity of the modified fine particles is 1 × 10 ⁶ Ω · cm or more.

According to the above-described method, when the electrophotographic toner is used in a developing process, a transfer process, or the like, it is possible to prevent the occurrence of charge leakage, transfer failure, and the like.

The method for producing an electrophotographic toner according to claim 9 of the present invention is a method as described above, wherein the modified fine particles are thermoplastic resin fine particles having a charge imparting function.

According to the above method, the same charge performance can be imparted by allowing a small amount of thermoplastic resin fine particles to exist on the surface of the toner core particles as compared with the case where the charge imparting agent is contained inside the toner core particles. . Further, by adjusting the type and amount of the thermoplastic resin fine particles, it is possible to control the polarity and the charging performance of the same toner core particles. As a result, there is an effect that the toner for electrophotography can be manufactured at low cost in terms of both the material cost and the manufacturing cost.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a manufacturing apparatus for performing a manufacturing method of the present invention.

FIG. 2 is a partially enlarged sectional view of the manufacturing apparatus shown in FIG.

FIG. 3 is a cross-sectional view showing another example of the manufacturing apparatus for performing the manufacturing method of the present invention.

4 is a partially enlarged sectional view of the manufacturing apparatus shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat treatment space (hot air flow field) 2 Hot air 3 Dispersion nozzle (toner particle supply port) 4 Piping 5 Quantitative feeder 6 Compressed gas generator 7 Hot air generator 8 Hot air supply nozzle (hot air supply port) 9 Straightening gas inlet 10 Heat treatment Apparatus 11 Cooling air 12 Cooling / collecting hopper (cooling vessel) 12a Opening 13 Outside air inlet 14 Cooling air generator 15 Cooling air introduction jacket 16 Collection box 17 Piping

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Toshihiko Murakami 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation (72) Inventor Katsuaki Sumida 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka F-term in Sharp Corporation (reference) 2H005 AA08 AB09 CB03 CB13 DA01 EA01 EA03 EA10

Claims (9)

[Claims] 1. A heat treatment space in which toner particles containing a binder resin are heat-treated, a hot air supply port for flowing hot air into the heat treatment space,
After heat-treating the toner particles using a heat treatment apparatus having a toner particle supply port for supplying the toner particles to the heat treatment space so as to be dispersed in the hot air, the heat treatment is performed in a cooling vessel provided on the downstream side of the heat treatment space. A method for producing an electrophotographic toner for cooling the toner particles dispersed in the toner, wherein an inner diameter D of the hot air supply port, an extension of a center line of the toner particle supply port, and an extension surface of an inner wall of the hot air supply port are formed. Let X / D ≦
A method for producing an electrophotographic toner, which is set to 0.6. 2. A heat treatment space in which toner particles containing a binder resin are heat-treated, a hot air supply port for flowing hot air into the heat treatment space,
After heat-treating the toner particles using a heat treatment apparatus having a toner particle supply port for supplying the toner particles to the heat treatment space so as to be dispersed in the hot air, the heat treatment is performed in a cooling vessel provided on the downstream side of the heat treatment space. A method for producing an electrophotographic toner, wherein the toner particles dispersed in the hot air are cooled, wherein the flow rate of the hot air in the hot air supply port is controlled to 2.55 m / s or more. . 3. The method for producing an electrophotographic toner according to claim 1, wherein the number of toner particle supply ports is four or more. 4. The heat treatment apparatus according to claim 1, further comprising a rectifying gas inlet for introducing a rectifying gas for adjusting the flow of the toner particles in the heat treatment space. A method for producing an electrophotographic toner. 5. The method for producing an electrophotographic toner according to claim 1, wherein the heat treatment and the cooling are performed in a dry gas atmosphere. 6. The electrophotography according to claim 1, wherein mixed particles obtained by adhering modified fine particles to the surface of toner core particles containing a binder resin are used as toner particles. Of manufacturing toner for toner. 7. The method for producing an electrophotographic toner according to claim 6, wherein the modified fine particles are thermoplastic resin fine particles having a glass transition temperature higher than the glass transition temperature of the toner core particles. 8. The modified fine particles having a volume resistivity of 1 × 10
7. The method for producing an electrophotographic toner according to claim ^{6, wherein the} resistivity is ⁶ Ω · cm or more. 9. The method for producing an electrophotographic toner according to claim 6, wherein said modified fine particles are thermoplastic resin fine particles having a charge imparting function.