JP5879908B2 - Method for producing carrier for electrostatic charge image two-component developer - Google Patents

Description

  The present invention relates to a method and apparatus for producing a carrier for an electrostatic charge image two-component developer.

In recent years, in electrophotographic technology, high image quality and environmental sustainability accompanying the advancement of the printing area are required. Conventional methods for producing a resin-coated carrier are roughly classified into a solution coating method and a dry coating method.
Solution coating methods include a method in which a resin dissolved in an organic solvent is spray-dried onto a carrier core, a method in which the carrier core is immersed in a resin dissolved in an organic solvent in a kneader, and the solvent is removed while stirring under heating and reduced pressure. There is.
On the other hand, the dry coating method includes a method of applying a strong shear force and heat after immobilizing the powder coating agent on the core surface with a stirring mixer. For example, Patent Document 1 discloses a method in which a coating layer is formed by stirring and mixing powdered resin particles and a core and applying heat using a high-speed stirring mixer, and then cooling and mixing to obtain a carrier. It is disclosed.
As another method, Patent Document 2 discloses a method of coating with a mechanical impact force by a surface treatment apparatus having a rotor and a liner.

JP-A-9-160307 JP 63-235959 A

  The problem to be solved by the present invention is a method and apparatus for producing a carrier for developing an electrostatic charge image, which has a high surface resin coverage of magnetic particles, less aggregation of the carrier, less peeling and release of the resin coating layer, and excellent image quality. Is to provide.

The present invention has been solved by the means described in <1> or <5> below. It is shown below with <2>-<4> and <6>-<8> which are preferable embodiments.
<1> Adhesion step of mixing magnetic particles and resin particles to form a resin particle adhesion layer on the surface of the magnetic particles, a casing having a raw material supply port and a discharge port, and a raw material from the raw material supply port toward the discharge port A rotating body provided with a rotating shaft in the same direction as the traveling direction, a heating means for heating a part of the casing, and a cooling means for cooling a part of the casing closer to the discharge port than the heating means An introduction step of introducing the magnetic particles having the resin particle adhesion layer into the apparatus having the resin particles from the raw material supply port; and in the apparatus, the magnetic particles having the resin particle adhesion layer are disposed on the inner wall of the casing and the rotating body. A coating forming step of continuously obtaining a magnetic particle having a resin coating layer by performing a heating and melting treatment, a cooling treatment and a crushing treatment by passing between Process for producing a carrier for loading image two-component developer,
<2> In the coating forming step, the magnetic particles having the resin particle adhesion layer are passed between the inner wall of the casing satisfying the following formulas (1) and (2) and the rotating body, and the resin coating layer The method for producing a carrier for an electrostatic charge image two-component developer according to the above <1>, wherein the magnetic particles having the above are discharged at a product temperature satisfying the formula (3),
1.0 <r _max / r _min <5.0 (1)
_{0.9 <r max / R <1.0} (2)
(Tg−50 ° C.) <Product temperature (° C.) <Tg (3)
( _Where r _max represents the maximum outer shape of the rotating body, r _min represents the minimum outer shape of the rotating body, R represents the inner diameter of the casing, and Tg represents the glass transition temperature of the resin particles.)
<3> The rotating body includes a spiral screw-shaped portion and a kneading-shaped portion to which mechanical shear is applied, and the cooling body in the casing is cooled by the cooling means. The method for producing a carrier for an electrostatic charge image two-component developer according to the above <1> or <2>, which has a kneading-shaped portion to which at least a mechanical share is applied,
<4> In the heat treatment part in the casing heated by the heating unit, the rotating body has a kneading-shaped portion to which at least a mechanical share is applied. <1> to <3> A method for producing a carrier for an electrostatic charge image two-component developer according to any one of the above,
<5> A casing having a raw material supply port and a discharge port, a rotating body provided with a rotation shaft in the same direction as the raw material traveling from the raw material supply port to the discharge port, and heating a part of the casing An apparatus for producing a carrier for an electrostatic charge image two-component developer, comprising: a heating unit; and a cooling unit that cools a part of the casing closer to the discharge port than the heating unit.
<6> The apparatus for producing a carrier for an electrostatic charge image two-component developer according to <5>, wherein a space between an inner wall of the casing and the rotating body satisfies the following formulas (1) and (2):
1.0 <r _max / r _min <5.0 (1)
_{0.9 <r max / R <1.0} (2)
(Wherein, r _max represents the maximum outer shape of the rotating body, r _min is the table the smallest outline of the rotating body, R represents the inner diameter of the casing.)
<7> The rotating body includes a spiral screw-shaped portion and a kneading-shaped portion to which mechanical shear is applied, and the cooling body in the casing is cooled by the cooling means. The apparatus for producing a carrier for an electrostatic charge image two-component developer according to the above <5> or <6>, which has a kneading-shaped portion to which at least a mechanical share is applied,
<8> In the heat treatment part in the casing heated by the heating means, the rotating body has a kneading-shaped portion to which at least a mechanical share is applied. <5> to <7> An apparatus for producing a carrier for an electrostatic charge image two-component developer according to any one of the above,

According to the invention described in <1> above, the surface resin coverage of the magnetic particles is higher, the carrier aggregation, the peeling and release of the resin coating layer are less, and the image quality is superior compared to the case without this configuration. A method for producing a carrier for developing an electrostatic image is provided.
According to the invention described in <2> above, the electrostatic charge image developing carrier has a higher surface resin coverage of the magnetic particles and less carrier aggregation compared to the case where the formulas (1) to (3) are not satisfied. A manufacturing method is provided.
According to the invention described in the above <3>, there is provided a method for producing a carrier for developing an electrostatic charge image with less carrier aggregation compared to a case where the present configuration is not provided.
According to the invention described in the above <4>, there is provided a method for producing a carrier for developing an electrostatic charge image with less carrier aggregation compared to the case without this configuration.
According to the invention described in the above <5>, the surface resin coverage of the magnetic particles is high, the carrier aggregation, the peeling and release of the resin coating layer are less, and the image quality is excellent as compared with the case without this configuration. An apparatus for producing an electrostatic charge image developing carrier is provided.
According to the invention described in <6> above, the electrostatic charge image developing carrier has a higher surface resin coverage of the magnetic particles and less carrier aggregation compared to the case where the formulas (1) to (3) are not satisfied. A manufacturing apparatus is provided.
According to the invention described in the above <7>, there is provided an apparatus for producing an electrostatic charge image developing carrier with less carrier aggregation compared to the case without this configuration.
According to the invention described in <8> above, there is provided an apparatus for producing a carrier for developing an electrostatic charge image with less aggregation of carriers as compared with the case where this configuration is not provided.

It is a schematic cross section showing an example of an apparatus for producing a carrier for an electrostatic charge image two-component developer according to the present embodiment. FIG. 6 is a partial schematic cross-sectional view of a casing and a rotating body in another example of the apparatus for producing an electrostatic charge image two-component developer carrier of the present embodiment. FIG. 3 is a schematic projection view from the downstream side in the passing direction in the manufacturing apparatus of FIG. 2. It is a schematic diagram which shows an example of the helical screw-shaped part with the feeding capability in a part of rotary body used for this embodiment. It is a schematic diagram which shows an example of the kneading shape part (phase 45 degrees) with which the mechanical share in a part of rotary body used for this embodiment is applied, and which has a feeding capability. It is a schematic diagram which shows an example of the kneading shape part (phase 135 degrees) with which the mechanical share in a part of rotary body used for this embodiment is applied, and which has a return capability. It is a schematic diagram which shows an example of the rotary body used for this embodiment. It is a schematic diagram which shows another example of the rotary body used for this embodiment. It is a schematic diagram which shows another example of the rotary body used for this embodiment. It is a schematic diagram which shows another example of the rotary body used for this embodiment.

Hereinafter, this embodiment will be described in detail.
In the present embodiment, the description “A to B” represents not only a range between A and B but also a range including A and B at both ends thereof. For example, if “A to B” is a numerical value range, “A or more and B or less” or “B or more and A or less” is represented according to the magnitude of the numerical value.

(Method and apparatus for producing carrier for electrostatic charge image two-component developer)
The method for producing a carrier for an electrostatic charge image two-component developer according to this embodiment (hereinafter, also simply referred to as “the method for producing a carrier according to this embodiment” or “the method for producing this embodiment”) includes magnetic particles and resin particles. An adhering step for forming a resin particle adhering layer on the surface of the magnetic particles, a casing having a raw material supply port and a discharge port, and a rotating shaft in the same direction as the raw material traveling from the raw material supply port to the discharge port The resin particles adhere to an apparatus having a rotating body provided with a heating means, a heating means for heating a part of the casing, and a cooling means for cooling a part of the casing closer to the discharge port than the heating means. A feeding step of feeding the magnetic particles having a layer from the raw material supply port, and passing the magnetic particles having the resin particle adhesion layer between the inner wall of the casing and the rotating body in the apparatus. Heat melting treatment by, characterized in that it comprises a coating formation step, to obtain the magnetic particles having a resin coating layer performs a cooling process and crushing process successively.

The apparatus for producing a carrier for an electrostatic charge image two-component developer according to this embodiment (hereinafter, also simply referred to as “a carrier production apparatus according to this embodiment” or “a production apparatus according to this embodiment”) A casing having an outlet, a rotating body provided with a rotation shaft in the same direction as the raw material traveling from the raw material supply port to the discharge port, a heating unit for heating a part of the casing, and the heating unit Furthermore, it has a cooling means which cools a part in the casing closer to the discharge port.
Further, the apparatus for producing an electrostatic charge image two-component developer carrier of the present embodiment is suitably used for the method of producing an electrostatic charge image two-component developer carrier of the present embodiment.
In addition, a preferable aspect of the manufacturing apparatus used in the method for manufacturing a carrier for an electrostatic charge image two-component developer of the present embodiment described below is preferable for the apparatus for manufacturing a carrier for an electrostatic charge image two-component developer of the present embodiment. Needless to say, this is also an aspect.

As described above, conventional methods for producing a resin-coated carrier are roughly classified into a solution coating method and a dry coating method.
The solution coating method uses a volatile organic solvent as a medium for the coating layer material, and has a problem such as an odor due to volatile organic compounds (VOC) remaining on the carrier without being dried after coating. In addition, as a problem that cannot be avoided in the manufacturing process, the amount of heat and electricity is required for drying and removing the solvent, cooling and collecting the removed solvent, and exhaust gas combustion for releasing the air used for drying to the atmosphere. ₂ occurs.
Further, in the dry coating method, the above problems of VOC and CO ₂ can be avoided. However, in the method described in Patent Document 1, for example, when heat treatment is performed at a temperature higher than the softening point of the resin, However, in the case where a plurality of resins and resistance control agents are coated, uniform dispersion in the coating layer is not possible because of forming aggregates. In addition, there is a problem that the carrier that has melted and adhered to the inner wall of the apparatus has to be cooled in a state in which the heat transfer efficiency has deteriorated, so that stirring share is applied for a long time and the coating film is peeled off. As a countermeasure, Patent Document 1 mentions that the number of revolutions during cooling is reduced, but this is not sufficient because the crushing ability is lowered.
In addition, the apparatus used in the method described in Patent Document 2 is not sufficient for forming a uniform coating layer because heat treatment cannot be performed. Moreover, it would be cumbersome to provide a separate heat treatment apparatus.
According to the manufacturing method and the manufacturing apparatus of the electrostatic charge image developing carrier of the present embodiment, the problems of VOC and CO ₂ can be avoided, the surface resin coverage of the magnetic particles is high, the carrier aggregation, the resin coating layer There is little peeling and separation, and the image quality obtained using the carrier is excellent.
Below, the manufacturing method and manufacturing apparatus of the carrier for electrostatic image two-component developers of this embodiment are demonstrated in detail.

<Adhesion process>
The method for producing a carrier for an electrostatic charge image two-component developer according to this embodiment includes an adhesion step of mixing magnetic particles and resin particles to form a resin particle adhesion layer on the surface of the magnetic particles.
The magnetic particles form a carrier core material (core) in the obtained carrier. The resin particles form a resin coating layer that covers the surfaces of the magnetic particles in the obtained carrier.
The magnetic particles having a resin particle adhesion layer on the surface formed in the adhesion step are not particularly limited as long as the resin particles adhere to the magnetic particle surface uniformly to some extent.
The amount of the resin particles used in the adhesion step is preferably 0.5 to 20% by weight, more preferably 1 to 10% by weight, and 2 to 7% by weight with respect to the weight of the magnetic particles. More preferably it is.
Further, for the purpose of mixing with the resin coating layer of the obtained carrier or adhering to the surface of the magnetic particles, in the adhering step, the magnetic particles and the resin particles together with the conductive particles, the charge control agent, the wax, and the coupling agent are used. You may mix well-known additives, such as.
Further, the order of mixing the magnetic particles, the resin particles, and these additives in the adhesion step is not particularly limited, and if desired, all materials may be mixed at one time. The removed coating resin may be mixed and the mixture may be added to the magnetic particles and mixed, or a plurality of coating resins may be divided and mixed.

As a device for mixing the magnetic particles and the resin particles used in the adhesion step, a known powder mixing device can be used, but it is possible to prevent excessive heat and mechanical impact force from being applied. In order to suppress reaggregation of conductive particles and aggregation and fusion of magnetic particles, it is preferable to use a device with a jacket.
The mixing device may be a batch type or a continuous type, and if it is a batch type, a mixing device with a stirrer such as a Henschel mixer or a Nauter mixer is preferably used. In this case, the coated product is once discharged into the hopper, and is supplied from there to a subsequent continuous heating / cooling device by a quantitative feeder.
If it is a continuous type, a single screw type or a twin screw type paddle mixer, a ribbon mixer, an extrusion mixer, etc. are mentioned. The obtained magnetic particles having a resin particle adhesion layer on the surface are once discharged into a hopper, and may be supplied to a continuous heating / cooling device at a subsequent stage by a quantitative feeder, or directly without a hopper. You may supply to the continuous heating and cooling apparatus. Further, it may be integrated with a subsequent continuous heating / cooling device.
The temperature of the mixture at the time of mixing is preferably not more than the glass transition temperature of the resin particles, more preferably at least 10 ° C. lower than the glass transition temperature of the resin particles, and 20 ° C. than the glass transition temperature of the resin particles. More preferably, the temperature is lower than the above.

[Magnetic particles]
The magnetic particles used in the adhesion step are not particularly limited, and magnetic metals such as iron, nickel, cobalt, and alloys of these magnetic metals with manganese, chromium, rare earth elements (for example, nickel-iron alloys, cobalt-iron). Alloys, aluminum-iron alloys, etc.), magnetic oxides such as ferrite and magnetite used alone in the core, magnetic particles such as magnetite dispersed in the resin, and magnetic materials such as ferrite as binders And a polymer core that is polymerized while dispersing a magnetic material such as magnetite in a monomer.

As a volume average particle diameter of a magnetic particle, 10-60 micrometers is preferable and 20-50 micrometers is more preferable.
The method for measuring the volume average particle diameter of the magnetic particles is not particularly limited, and may be measured by a known method. For example, a laser diffraction / scattering particle size distribution analyzer (LS Particle Size Analyzer: LS13 320, BECKMAN COULTER) (Beckman Coulter, Inc.) is preferable. The obtained particle size distribution is divided into particle size ranges (channels), and the volume cumulative distribution is subtracted from the small particle size side to _{obtain a} volume average particle size D _50v .

[Resin particles]
The resin particles used in the attaching step are not particularly limited, and known resin particles may be used.
Specific examples of the resin of the resin particles include styrenes such as styrene, chlorostyrene, and methylstyrene; methyl methacrylate, methyl acrylate, propyl acrylate, lauryl acrylate, cyclohexyl methacrylate, methacrylic acid, acrylic acid, butyl methacrylate, butyl acrylate, Α-methylene aliphatic monocarboxylic acids such as 2-ethylhexyl acrylate and ethyl methacrylate; nitrogen-containing acrylics such as dimethylaminoethyl methacrylate; nitriles such as acrylonitrile and methacrylonitrile; 2-vinylpyridine, 4-vinylpyridine and the like Homopolymers or copolymers such as vinyl pyridines; vinyl ethers; vinyl ketones; olefins such as ethylene, propylene and butadiene; Imide backbone nitrogen-containing resins such as melamine; methyl silicone resin, silicone resins such as methylphenyl silicone resin; bisphenol, and a glycol such as polycondensed polyesters like. Among these, acrylic resins are preferable, and homopolymers of methyl methacrylate, methyl acrylate, propyl acrylate, and cyclohexyl acrylate, or copolymers obtained by copolymerizing at least these monomers are particularly preferable.
The volume average particle diameter of the resin particles used in the adhesion step is preferably 0.01 to 1 μm, preferably 0.05 to 0.5 μm, from the viewpoint of uniform adhesion to the surface of the magnetic particles, dispersibility of the conductive particles, and the like. Is more preferable. Further, the glass transition temperature of the resin particles is preferably 70 to 120 ° C.

[Conductive particles]
The conductive particles used in the present embodiment are not particularly limited as long as the particles exhibit conductivity, but specifically, metals such as carbon black, various metal powders, titanium oxide, tin oxide, magnetite, and ferrite. An oxide etc. are mentioned. Carbon black is particularly preferred because high conductivity can be imparted with a small amount of addition, and the degree of conductivity can be easily controlled by the blending amount.
Further, these conductive particles preferably have a volume primary particle diameter of 0.01 μm to 0.5 μm. When the volume primary particle diameter is in this range, the mixing / dispersibility with the resin particles is good and the dispersibility in the coating layer is good.
As addition amount of electroconductive particle, the addition amount less than 20 volume% of the resin coating layer or the resin particle to be used is preferable. Moreover, when adding 20 volume% or more, dispersion | distribution control of the powder in a resin coating layer becomes difficult, and control of an electrical resistance may become difficult.

[Other additives]
In the adhesion step, a negative charge control agent may be added. That is, the resin coating layer of the carrier obtained by the production method of the present embodiment may contain a negative charge control agent.
Negative charge control agents include trimethylethane dyes, metal complexes of salicylic acid, metal complexes of benzylic acid, copper phthalocyanine, perylene, quinacridone, azo pigments, metal complex azo dyes, azochrome complexes, etc. Examples include dyes, calixarene type phenolic condensates, cyclic polysaccharides, resins containing at least one of carboxyl groups and sulfonyl groups.
The content of the negative charge control agent is preferably in the range of 0.001% by mass to 1.0% by mass with respect to the mass of the magnetic particles, and is 0.01% by mass to 0.8% by mass. More preferably, it is the range. When the amount is in the above range, a sufficient effect on the toner charge rising property can be obtained, and the chargeability of the carrier itself is excellent.

In the adhesion step, a negative charge control agent may be added. That is, the resin coating layer of the carrier obtained by the manufacturing method of the present embodiment may contain wax.
Waxes are usually hydrophobic, are relatively soft at room temperature, and have low film strength. This originates from the molecular structure of the wax, but due to this property, if wax is present in the resin coating layer, particles called external additives added to the toner surface, or toner components such as toner bulk components are transferred to the carrier surface. It is hard to adhere to. Even if it adheres, the surface of the carrier is renewed by peeling off the wax at the adhesion level at the molecular level, and the carrier surface is not easily contaminated.
The wax used in the present embodiment is not particularly limited. For example, paraffin wax and derivatives thereof, montan wax and derivatives thereof, microcrystalline wax and derivatives thereof, Fischer-Tropsch wax and derivatives thereof, polyolefin wax and derivatives thereof Derivatives and the like. Derivatives include oxides, polymers with vinyl monomers, and graft modified products. In addition, alcohol, fatty acid, plant wax, animal wax, mineral wax, ester wax, acid amide, and the like may be used. Moreover, you may use another well-known thing.
The melting point of the wax is preferably 60 ° C. or higher and 200 ° C. or lower, and more preferably 80 ° C. or higher and 150 ° C. or lower. Within the above range, the carrier fluidity is excellent.

Moreover, in order to improve the adhesiveness between the magnetic particle surface and the resin coating layer, the magnetic particle surface may be subjected to a coupling treatment.
Examples of coupling agents include silane coupling agents, silicone oils, titanate coupling agents, and aluminum coupling agents. These may be used individually by 1 type and may use 2 or more types together. Among these, a silane coupling agent is preferable.
As the silane coupling agent, any type of chlorosilane, alkoxysilane, silazane, and special silylating agent may be used. Specifically, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, tetramethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, tetraethoxysilane, Methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, diphenyldiethoxysilane, isobutyltrimethoxysilane, decyltrimethoxysilane, hexamethyldisilazane, N, O- (bistrimethylsilyl) acetamide, N, N-bis (Trimethylsilyl) urea, tert-butyldimethylchlorosilane, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxy Silane, γ-methacryloxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-mercapto Examples include propyltrimethoxysilane, γ-chloropropyltrimethoxysilane, and γ-aminopropyltriethoxysilane.
Examples of titanate coupling agents include “Plenact KR TTS”, “Plenact KR 46B”, “Plenact KR 55”, “Plenact KR 41B”, “Plenact KR 38S”, “Plenact KR 138S”, “Prenact K”. 238S "," Plenact 338X "," Plenact KR 44 "," Plenact KR 9SA "," Plenact KR ET "(all of which are manufactured by Ajinomoto Fine Techno Co., Ltd.) and the like, Examples thereof include alkyl acetoacetate aluminum diisopropylate (“Plenact AL-M” manufactured by Ajinomoto Fine Techno Co., Ltd.).

<Input process and coating formation process>
The method for producing a carrier for an electrostatic charge image two-component developer according to the present embodiment includes a casing having a raw material supply port and a discharge port, and a rotation axis in the same direction as the raw material traveling direction from the raw material supply port to the discharge port. The resin particle adhesion layer in an apparatus comprising: a rotating body provided; a heating unit that heats a part of the casing; and a cooling unit that cools a part of the casing closer to the discharge port than the heating unit. And heating the magnetic particles having the resin particle adhesion layer by passing between the inner wall of the casing and the rotating body in the apparatus. A coating forming step of obtaining magnetic particles having a resin coating layer by continuously performing a melting treatment, a cooling treatment and a crushing treatment is included.

The charging speed of the magnetic particles having the resin particle adhesion layer in the charging process to the apparatus is preferably selected below the feeding capacity of the apparatus. When the charging speed is equal to or less than the feeding capability of the apparatus, the occurrence of clogging is suppressed, and the driving system of the apparatus is not overloaded, and continuous operation is easy.
Further, the charging method may be performed intermittently or continuously.

In the coating forming step, it is important to continuously perform the heat melting treatment, the cooling treatment, and the crushing treatment.
In the heating and melting treatment, the magnetic particles having the resin particle adhesion layer added are heated by the heating means while being stirred by the rotating body, and the adhered resin particles are melted to form a resin coating layer on the surface of the magnetic particles. Is done.
Subsequently, by performing a cooling process by a cooling means subsequent to the heating and melting process, the magnetic particles having the resin coating layer heated in the heating and melting process are cooled, and the resin coating layer is solidified.
In the crushing treatment, some of the magnetic particles having the resin coating layer cooled by the cooling treatment may be adhered to each other, and therefore, the stirring is performed by the rotating body. To obtain magnetic particles having a resin coating layer with few coarse aggregates. The pulverization treatment may be performed simultaneously with the cooling treatment or continuously after the cooling treatment, but the pulverization treatment simultaneously with the cooling treatment is more effective in suppressing peeling and release of the resin coating layer. Is preferable.
Further, in the coating forming step, passing the magnetic particles having the resin particle adhesion layer between the inner wall of the casing and the rotating body rotates the rotating body, and causes the magnetic particles having the resin particle adhesion layer to be rotated. This is done by stirring.
If the heat-melting treatment, the cooling treatment, and the crushing treatment are not performed continuously, the magnetic particles having the resin coating layer melted in the heat-melting treatment are aggregated as time passes after the heat-melting treatment. If the aggregate is crushed after cooling, the resin coating layer is often peeled off or released. Furthermore, a large amount of the resin derived from the molten resin particles adheres to the inner wall of the casing of the apparatus, which not only lowers the cooling efficiency but also requires a lot of time and shearing force for the crushing treatment. This results in a lot of peeling and liberation.

The heating temperature in the heat-melting treatment is preferably higher than the glass transition temperature of the used resin particles, and more preferably 150 to 250 ° C. Within the above range, the resin can be easily melted, and thermal decomposition of the resin is suppressed.
Moreover, it is preferable that it is below the glass transition temperature of the used resin particle, as for the cooling temperature in the said cooling process, it is more preferable that it is 0-50 degreeC, and it is still more preferable that it is 0-40 degreeC. In the above embodiment, aggregation between carriers is suppressed.
The product temperature of the magnetic particles having the resin coating layer discharged from the outlet through the coating forming step, that is, the temperature at the time of discharging the particles themselves is 0 ° C. to the glass transition temperature of the used resin particles or less. It is preferable that it is 20 degreeC-(The glass transition temperature of the used resin particle -10 degreeC) or less. In the above embodiment, aggregation between carriers is suppressed.
The thickness of the resin coating layer formed in the coating forming step is preferably in the range of 0.1 μm to 5 μm, and more preferably in the range of 0.2 μm to 3 μm. Within the above range, it is easy to form a uniform and flat resin coating layer on the surface of the magnetic particles, and aggregation of carriers is suppressed.

Each part of the apparatus used in the charging process and the coating forming process will be described below.
The apparatus includes a casing having a raw material supply port and a discharge port, and a rotating body provided with a rotating shaft in the same direction as the raw material traveling from the raw material supply port to the discharge port in the casing. ing.
The position of the raw material supply port and the discharge port in the casing is not particularly limited as long as the raw material charged into the apparatus passes between the inner wall of the casing and the rotating body and can perform the coating forming step. However, it is preferable to have the raw material supply port near one end of the rotating body and the discharge port near the other end of the rotating body.
The apparatus further includes a heating unit that heats a part of the casing, and further includes a cooling unit that cools a part of the casing closer to the discharge port than the heating unit.
It is preferable that the heat processing part heated by the said heating means in the said casing and the cooling processing part cooled by the said cooling means in the said casing are contacting.

Moreover, it is preferable that the said casing in the said apparatus has a jacket structure as a heating means and a cooling means. By having the said jacket structure, the temperature adjustment of heating and cooling is easy by a site | part. Moreover, it is preferable that the said jacket structure is provided in contact with the outer side of the said casing.
Moreover, it is preferable that the apparatus has a uniaxial or biaxial rotating body in the casing.
The rotating body may control the stirring shear force as desired. For example, the shape of the rotating body and the stirring speed are changed depending on the part of the rotating body, the shape of the casing side is changed without changing the rotating body, or the stirring by the rotating body is performed by the clearance between the rotating body and the casing. Shear force is easily controlled.
Specific examples of the apparatus used in the present embodiment include, for example, a paddle mixer, a screw mixer, a turbulizer, a continuous kneader, and a twin screw kneader provided with heating and cooling means, but are not limited thereto. It is not something. Among these, a twin-screw extrusion kneader provided with heating and cooling means is preferable.

The manufacturing method of this embodiment may include other known steps as necessary.
In addition, the manufacturing method of the present embodiment includes, as necessary, a classification step of classifying the magnetic particles having the obtained resin coating layer and / or the obtained resin coating layer after the coating formation step. A sieving step of sieving the magnetic particles having may be included.
The classification means and sieve used in the classification step and the sieving step are not particularly limited, and known ones may be used as desired.

An example of an apparatus for producing a carrier for an electrostatic charge image two-component developer according to this embodiment will be described below with reference to the drawings.
In the electrostatic charge image two-component developer carrier production apparatus 10 shown in FIG. 1, magnetic particles having a resin particle adhesion layer are introduced into a casing 14 through a raw material supply port 16 from a particle supply device 12. The manufacturing apparatus 10 is a twin screw extrusion kneader. The charged magnetic particles having the resin particle adhesion layer pass between the casing 14 and the rotating body 18 by the rotation of the rotating body 18, pass through the heat processing unit 20 and the cooling processing unit 22, and are discharged from the outlet 24. It is discharged as magnetic particles having a resin coating layer. In addition, the particles are also crushed by the rotation of the rotating body 18. Note that the rotating body 18 shown in FIG. 1 is a rotating body having a helical screw shape as a whole.
A jacket (not shown) capable of partially adjusting the temperature is wound around the outer peripheral portion of the casing 14 in the heat processing unit 20 and the cooling processing unit 22 as a heating unit and a cooling unit. The temperature of the heat processing unit 20 and the cooling processing unit 22 is adjusted by the jacket. Moreover, the heat processing part 20 and the cooling process part 22 in the manufacturing apparatus 10 are provided continuously.

In the coating forming step, the magnetic particles having the resin particle adhesion layer are passed between the inner wall of the casing satisfying the following formulas (1) and (2) and the rotating body, and the resin coating layer is It is preferable that the magnetic particles to be discharged are discharged at a product temperature satisfying the formula (3). In the above embodiment, heat during heat-melting treatment is uniformly applied to the particles, the surface coverage of the obtained magnetic particles is high, the crushing treatment can be effectively performed, carrier aggregation, resin coating layer Peeling and release are suppressed.
1.0 <r _max / r _min <5.0 (1)
_{0.9 <r max / R <1.0} (2)
(Tg−50 ° C.) <Product temperature (° C.) <Tg (3)
( _Where r _max represents the maximum outer shape of the rotating body, r _min represents the minimum outer shape of the rotating body, R represents the inner diameter of the casing, and Tg represents the glass transition temperature of the resin particles.)
Moreover, in the manufacturing apparatus of this embodiment, it is preferable that the inner wall of the said casing and the said rotary body satisfy | fill said Formula (1) and Formula (2). In the above embodiment, heat during heat-melting treatment is uniformly applied to the particles, the surface coverage of the obtained magnetic particles is high, the crushing treatment can be effectively performed, carrier aggregation, resin coating layer Peeling and release are suppressed.
FIG. 2 and FIG. 3 are shown as an example of how to take the values of the expressions (1) and (2).
FIG. 2 is a partial schematic cross-sectional view of a casing and a rotating body in another example of the apparatus for manufacturing an electrostatic charge image two-component developer according to the present embodiment, and FIG. 3 is a view through the manufacturing apparatus of FIG. It is a schematic projection view from the direction downstream side.
A rotating body 32 is provided in the casing 30 shown in FIG. The rotating body 32 has a structure in which large-sized portions 34 and small-shaped portions 36 are alternately provided in the particle passing direction B. The rotating body 32 is a rotating body that rotates in the direction A about the rotation shaft 38.
In the manufacturing apparatus shown in FIG. 2, r _max is a value obtained by doubling the distance between the position farthest from the rotation axis and the rotation axis in the portion 34 having a large outer shape on the surface perpendicular to the rotation axis 38. The large outer portion 34 of the rotating body 32 has a constant distance from the rotary shaft 38 in a plane perpendicular to the rotary shaft 38, and therefore the diameter of the circle 40 of the outer shape of the large outer portion 34 is as follows. r _max .
In the manufacturing apparatus shown in FIG. 2, r _min is a value obtained by doubling the distance between the rotation axis and the position closest to the rotation axis in the portion 36 having a small outer shape on the surface perpendicular to the rotation axis 38. The portion 36 having a small outer shape in the rotating body 32 has a constant distance from the rotation shaft 38 in a plane perpendicular to the rotation shaft 38. r _min .
Furthermore, as shown in the manufacturing apparatus shown in FIG. 2, R is the distance between the two most distant points among any two points on the inner wall of the casing 30 on the plane perpendicular to the rotation shaft 38.
The shape of the casing is not particularly limited, but is preferably cylindrical from the viewpoint that the rotating body easily rotates and that the space between the rotating body and the casing inner wall depends on the shape of the rotating body.

The rotating body preferably has a spiral screw-shaped portion and a kneading-shaped portion to which mechanical shear is applied. If it is the said aspect, a crushing process can be performed effectively and aggregation of a carrier is suppressed. In the present embodiment, “mechanical shear is applied” means that a shear stress is applied to the raw material to be used, that is, the particles. As an example of the helical screw-shaped part, a member shown in FIG. 4 is preferably exemplified.
Moreover, in the cooling process part in the said casing cooled by the said cooling means, it is preferable that the said rotary body has a kneading-shaped part to which a mechanical share is applied at least. If it is the said aspect, a crushing process can be performed effectively and aggregation of a carrier is suppressed more.
Furthermore, in the heat treatment part in the casing heated by the heating means, it is also preferable that the rotating body has a kneading shape portion to which at least mechanical shear is applied. If it is the said aspect, a crushing process can be performed effectively and aggregation of a carrier is suppressed more.
As an example of the kneading shape part to which the mechanical shear is applied, a member shown in FIG. 5 or 6 is preferably exemplified.
The member shown in FIG. 5 is an example of a kneading-shaped portion (phase 45 °) that is mechanically sheared and has the ability to feed downstream in the passing direction B, and the member shown in FIG. This is an example of a kneading-shaped portion (phase 135 °) that is sheared and has the ability to return to the upstream side in the passing direction B.
The rotating body is preferably a rotating body whose shape can be changed in each part as desired.

Moreover, the preferable example of the rotary body (screw) used suitably for this embodiment to FIGS. 7-10 is shown.
FIG. 7 shows a rotating body 50 composed of only a spiral screw-shaped portion 56 having both feeding capabilities in the heat processing section 52 and the cooling processing section 54.
FIG. 8 shows a rotating body 50 that includes only a helical screw-shaped portion 56 having a feeding capability in the heating processing section 52 and only a kneading-shaped portion 58 having a feeding capability in the cooling processing section 54. .
FIG. 9 shows that the heat treatment unit 52 includes a spiral screw-shaped portion 56 having a feeding capability and a kneading shape portion 58 having a feeding capability, and the cooling processing unit 54 has a kneading configuration having a feeding capability. The rotating body 50 includes only the portion 58.
FIG. 10 shows that the heat processing unit 52 includes a helical screw-shaped portion 56 having a feeding capability, a kneading-shaped portion 58 having a feeding capability, and a kneading-shaped portion 60 having a returning capability. The rotary body 50 includes only the kneading shape portion 58 having a feeding ability.
In addition, the square frame and the diagonal line in the kneading shape part 58 with the feeding ability and the kneading shape part 60 with the returning ability shown in FIG. 8 to FIG. 10 are described in order to clearly show the parts concerned. Needless to say, the description is not in the actual rotating body.
Further, the spiral screw-shaped portion 56 having feeding ability is the portion shown in FIG. 4, and the kneading-shaped portion 58 having feeding ability is the portion shown in FIG. 5 as the kneading-shaped portion 60 having returning ability. Are preferably each shown in FIG.

(Static charge image two-component developer)
The electrostatic charge image two-component developer of the present embodiment is a two-component system containing the carrier manufactured by the carrier manufacturing method of the present embodiment or the carrier manufacturing apparatus of the present embodiment and the electrostatic charge image developing toner. An electrostatic charge image developer.
The electrostatic image developing toner used in the exemplary embodiment is not particularly limited, and a known toner is used.
The mixing ratio of the electrostatic image developing toner of the present embodiment and the carrier in the electrostatic charge image two-component developer is not particularly limited and may be appropriately selected depending on the intended purpose. The (weight ratio) is preferably in the range of toner: carrier = 1: 100 to 30: 100, and more preferably in the range of 3: 100 to 20: 100.
The carrier for an electrostatic charge image two-component developer according to the present embodiment is a carrier manufactured by the carrier manufacturing method according to the present embodiment or the carrier manufacturing apparatus according to the present embodiment.

(Cartridge, image forming method and image forming apparatus)
The cartridge of this embodiment is a cartridge that contains at least the electrostatic charge image two-component developer of this embodiment. In addition, it is preferable that the cartridge of this embodiment is detachable from the image forming apparatus.
When used in the developing device, the image forming method, or the image forming apparatus, the toner cartridge may contain toner alone, or the developer cartridge may contain the electrostatic charge image two-component developer of this embodiment. In addition, the process cartridge may include at least developing means for developing the electrostatic latent image formed on the image carrier with the electrostatic charge image two-component developer of the present embodiment to form a toner image. .
In addition, the process cartridge according to the present embodiment may include other members such as a charge removing unit as necessary.

The image forming method of the present embodiment is not particularly limited except that the electrostatic image two-component developer of the present embodiment is used as a developer, but a latent image forming step of forming an electrostatic latent image on the surface of the image carrier. A developing step of developing the electrostatic latent image formed on the surface of the image carrier with a developer containing toner to form a toner image; and the toner image formed on the surface of the image carrier And a fixing step of fixing the toner image transferred to the surface of the transfer target, and the developer containing the toner is the electrostatic charge image two-component developer of the present embodiment. preferable.
As an image forming method of the present embodiment, the electrostatic image two-component developer of the present embodiment is prepared, and an electrostatic image is formed and developed by a conventional electrophotographic copying machine using the developer. The image is electrostatically transferred onto a transfer paper and fixed by a heat fixing device to form a copy image.

Each of the steps in the image forming method is a general step per se, and is described in, for example, JP-A-56-40868 and JP-A-49-91231. Note that the image forming method of the present embodiment can be carried out by using a known image forming apparatus such as a copying machine or a facsimile machine.
The electrostatic latent image forming step is a step of forming an electrostatic latent image on an image carrier (photoconductor).
The developing step is a step of developing the electrostatic latent image with a developer layer on a developer holding member to form a toner image. The developer layer is not particularly limited as long as it contains the electrostatic charge image two-component developer of this embodiment.
The transfer step is a step of transferring the toner image onto a transfer target. Examples of the transfer medium in the transfer process include an intermediate transfer medium and a recording medium such as paper.
In the fixing step, for example, there is a method of forming a copy image by fixing the toner image transferred onto the transfer paper by a heating roller fixing device in which the temperature of the heating roller is set to a constant temperature.
The cleaning step is a step of removing the electrostatic charge image developer remaining on the image carrier.
As the recording medium, known media can be used, for example, paper used for electrophotographic copying machines, printers, OHP sheets, etc. For example, the surface of plain paper is made of resin, etc. Coated coated paper, art paper for printing, and the like can be suitably used.

  The image forming method of the present embodiment may further include a recycling step. The recycling step is a step of transferring the electrostatic charge image developing toner collected in the cleaning step to a developer layer. The image forming method including the recycling process is performed using an image forming apparatus such as a toner recycling system type copying machine or facsimile machine. Further, the present invention may be applied to a recycling system in which the cleaning process is omitted and toner is collected simultaneously with development.

The image forming apparatus of the present embodiment is not particularly limited except that it contains the electrostatic charge image two-component developer of the present embodiment as a developer, but an image carrier, a charging unit that charges the image carrier, Exposure means for exposing the image holding member to form an electrostatic latent image on the image holding member; developing means for developing the electrostatic latent image with a developer containing toner to form a toner image; It is preferable that the developer includes a transfer unit that transfers the toner image from the image holding member to the transfer target, and the developer including the toner includes the electrostatic charge image two-component developer of the present embodiment.
The image forming apparatus of the present embodiment is not particularly limited as long as it includes at least the image holding member, the charging unit, the exposure unit, the developing unit, and the transfer unit as described above, but other necessary. Depending on the situation, a fixing means, a cleaning means, a static elimination means and the like may be included.
In the transfer unit, the transfer may be performed twice or more using an intermediate transfer member. Examples of the transfer medium in the transfer unit include an intermediate transfer medium and a recording medium such as paper.

  The image carrier and each of the above-described units can preferably use the configurations described in the respective steps of the image forming method. As each of the above-described means, a known means in the image forming apparatus can be used. In addition, the image forming apparatus according to the present embodiment may include means and devices other than the above-described configuration. Further, the image forming apparatus according to the present embodiment may simultaneously perform a plurality of the above-described means.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated more concretely in detail, this embodiment is not limited to a following example.

<Preparation of ferrite particles>
After mixing 74 parts by mass of Fe ₂ CO ₃ , 25 parts by mass of MnO _{2 and} 1 part by mass of ZnO, mixing and pulverizing with a wet ball mill for 25 hours, granulating and drying by spray drying, 800 ° C., 7 Temporary calcination 1 was performed. This was pulverized with a wet ball mill for 2 hours, further granulated and dried with a spray dryer, and then pre-baked 2 at 1,150 ° C. for 6 hours using a rotary kiln. The calcined product thus obtained was pulverized with a wet ball mill for 5 hours, further granulated and dried again with a spray dryer, and then subjected to main firing at a temperature of 1,150 ° C. for 12 hours using an electric furnace. The main calcination was performed in an atmosphere adjusted so that the oxygen ratio in the mixed gas of nitrogen and oxygen was 12% by volume. And the ferrite particle of the volume average particle diameter of 37 micrometers was produced through the crushing process and the classification process.

<Preparation of resin particle-attached magnetic particles>
Ferrite particles (37 μm) 100 parts by mass Styrene / MMA (methyl methacrylate) (30:70) copolymer resin particles (average particle size 0.20 μm, glass transition temperature 90 ° C.) 2.5 parts by mass Carbon black (VXC72, Cabot Corporation) Manufactured, 0.20 μm) 0.02 parts by mass The glass transition temperature of the resin was determined by a DSC (Differential Scanning Calorimeter) measurement method, and was determined from the main maximum peak measured in accordance with ASTM D3418-8. For the measurement of the main maximum peak, DSC-7 manufactured by PerkinElmer is used. The temperature correction of the detection part of this apparatus uses the melting point of indium and zinc, and the correction of heat quantity uses the heat of fusion of indium. As the sample, an aluminum pan was used, an empty pan was set as a control, and the measurement was performed at a heating rate of 10 ° C./min.

  First, the above raw materials were put into a Henschel mixer, and stirred and mixed at 1,200 rpm × 20 minutes to produce resin-adhered magnetic particles.

Example 1
In the twin-screw extrusion kneader of FIG. 1, the resin-adhered magnetic particles are continuously applied at 10 kg / h to an apparatus having r _max / r _min = 5.0 and r _max / R = 0.99 with the screw configuration of FIG. Supply the jacket temperature at the front stage heat treatment section: 200 ° C., jacket temperature at the rear stage cooling processing section: 20 ° C., set the screw rotation speed so that the residence time is 1 minute, and the product temperature from the discharge port is 70 ° C. It was collected.

(Example 2)
The resin-attached magnetic particles were continuously supplied at 10 kg / h to an apparatus having r _max / r _min = 1.5 and r _max / R = 0.99 with the same twin-screw extrusion kneader and screw configuration as in Example 1. Then, the jacket temperature of the front-stage heat treatment part: 200 ° C., the jacket temperature of the rear-stage cooling treatment part: 20 ° C., the screw rotation speed was set so that the residence time was 1 minute, and the product temperature was recovered from the outlet at 70 ° C. .

(Example 3)
In the same twin-screw extrusion kneader as in Example 1, the resin-adhered magnetic particles were placed at 10 kg / h in an apparatus having r _max / r _min = 1.5 and r _max / R = 0.99 with the screw configuration of FIG. And the jacket temperature of the front-stage heat treatment part: 200 ° C., the jacket temperature of the rear-stage cooling treatment part: 20 ° C., and the treatment temperature of 70 ° C. were collected from the discharge port under the treatment conditions of 1 minute.

Example 4
In the same twin screw extrusion kneader as in Example 1, with the screw configuration of FIG. 9, r _max / r _min = 1.5 and r _max / R = 0.99 were placed in an apparatus with 10 kg / h of the resin-attached magnetic particles. And the jacket temperature of the front-stage heat treatment part: 200 ° C., the jacket temperature of the rear-stage cooling treatment part: 20 ° C., and the treatment temperature of 70 ° C. were collected from the discharge port under the treatment conditions of 1 minute.

(Comparative Example 1)
A batch type high-speed mixer (capacity 5L, 2 blades) is charged with 2kg of resin-adhered magnetic particles, jacket heating medium temperature 210 ° C, peripheral speed of rotating 2 blades 8m / sec, product temperature 200 ° C After reaching, the rotation was maintained for 30 minutes, and after cooling at a jacket heating medium temperature of 20 ° C. for 60 minutes, the product was recovered at a product temperature of 70 ° C.

(Comparative Example 2)
The resin-adhered magnetic particles are continuously supplied at 10 kg / h to the same twin-screw extrusion kneader and screw configuration and dimensions as in Example 3, and the jacket temperature of the heat treatment section is 200 ° C., and the residence time is 1 minute. Under the conditions, the product was recovered from the outlet at a product temperature of 195 ° C. and naturally cooled. In addition, the cooling process in a cooling process part was not performed.
Since the discharged product is agglomerated powder and cannot be evaluated as it is, the discharged product was pulverized to primary particles with a Comil pulverizer (punching metal φ1 mm).

(Example 5)
In the same twin-screw extrusion kneader as in Example 1, the resin-adhered magnetic particles were continuously applied at 10 kg / h to an apparatus having r _max / r _min = 10 and r _max / R = 0.80 with the screw configuration of FIG. The product was recovered at a product temperature of 70 ° C. from the outlet under the processing conditions of jacket temperature of the heat treatment unit: 200 ° C., jacket temperature of the rear cooling treatment unit: 20 ° C., and residence time of 1 minute.

<Production of developer>
10 parts of toner (manufactured by Fuji Xerox Co., Ltd., toner for ApeosPort C6500) and 100 parts of the carrier obtained in Examples 1 to 5 and Comparative Examples 1 and 2 were stirred with a V blender at 40 rpm × 20 minutes, and 212 μm. The developers of Examples 1 to 4 and Comparative Examples 1 to 3 were obtained by sieving with sieves having the same mesh size.

(Evaluation)
Using each of the developers obtained in Examples 1 to 5 and Comparative Examples 1 and 2 and using Apeos Port C6500 manufactured by Fuji Xerox Co., Ltd., an image with an image density of 10% was output as a 100,000-sheet image. The following evaluation was conducted. The results are shown in Table 1.

<75 μm net amount>
The prepared carrier is subjected to sieving using a sieving mesh with an opening of 75 μm, and the mass of the carrier that has passed through the sieving mesh is calculated. Calculated with

<Coating ratio of resin coating layer>
It was determined by XPS measurement (X-ray photoelectron spectroscopy measurement). As an XPS measurement device, JPS80 manufactured by JEOL Ltd. was used, and measurement was performed using an MgKα ray as an X-ray source, setting an acceleration voltage to 10 kV, and an emission current to 20 mV. The main element (carbon) constituting and the main elements (iron and oxygen) constituting the ferrite particles were measured.

<Carrier surface observation>
Toner was blown off from each developer before output and after output of 100,000 images, and surface observation by SEM was performed. Surface observation was performed by FE-SEM (S4100 manufactured by Hitachi, Ltd.), and the surface of CA was observed at a magnification of × 3,000.
The evaluation results are shown in Table 1.

In Examples 1 to 4, the coat was made uniform, and the image after 100,000 sheets was in a state where the coat was not peeled off and the core was hardly exposed.
In Comparative Example 1, as compared with the Example, the coating was rough from the CA before output, and the core exposure was conspicuous.
Comparative Example 2 had a uniform coating before crushing, but was crushed with an external crusher because the yield was very small. As a result, the crater-like crushed residue remained on the coating surface, and the core was exposed at that portion.
In Comparative Example 3, the coating state before output was good, but CA peeling after 100,000 sheets was noticeable. This is presumably because the heat at the time of heating was not sufficiently transmitted and peeled off over time due to the weak adhesion between the core and the resin.

<Change in image quality: white spots due to carrier skipping>
Count the number of carriers flying in the solid image part of the A3 image output to the 100,000th sheet. If the number of carriers is 3 or less, ○ if 4 or more, 9 or less, Δ, 10 or more The case of was evaluated as x.
When the cause of the carrier jump was confirmed, it was found that the carrier resistance was lowered by the exposure of the core, and the carrier was developed in the image area.
For this reason, this manufacturing method which can obtain a favorable coating over time can provide a carrier with high image quality maintenance.

  In Table 1, A represents that the screw of the processing unit has a feed screw shape, and B represents that the screw of the processing unit has a feed kneading screw shape. A and B represent that the screw of the processing unit has both A and B shapes.

10: Electrostatic charge image two-component developer carrier production apparatus, 12: particle supply apparatus, 14, 30: casing, 16: raw material supply port, 18, 32, 50: rotating body, 20, 52: heat treatment section, 22, 54: Cooling processing unit, 24: Discharge port, 34: Large portion of the outer shape of the rotating body, 36: Small portion of the outer shape of the rotating body, 38: Rotating shaft, 40: Outer shape of the large portion 34 of the rotating body , 42: Circle of the outer shape of the small part 36 of the outer shape of the rotating body, 56: Spiral screw-shaped portion with feeding ability, 58: Kneading-shaped portion with feeding ability, 60: Knee with returning ability Bing shape portion, A: rotating direction of rotating body, B, D: raw material passing direction, R: inner diameter of casing 30, r _max : maximum outer shape of rotating body 32, r _min : minimum outer shape of rotating body 32

Claims (3)

An adhesion step of mixing magnetic particles and resin particles to form a resin particle adhesion layer on the surface of the magnetic particles;
A casing having a raw material supply port and a discharge port, a rotating body provided with a rotating shaft in the same direction as the raw material traveling from the raw material supply port to the discharge port, a heating means for heating a part of the casing, And a charging step of charging the magnetic particles having the resin particle adhesion layer from the raw material supply port into an apparatus having a cooling unit that cools a part of the casing closer to the discharge port than the heating unit, and
In the apparatus, by passing the magnetic particles having the resin particle adhesion layer between the inner wall of the casing and the rotating body, a heat melting treatment, a cooling treatment and a crushing treatment are continuously performed to form a resin coating layer. coating formation step of obtaining a magnetic particle having, only including,
The heating temperature in the heat melting treatment is 150 to 250 ° C.,
In the coating formation step, the magnetic particles having the resin particle adhesion layer are passed between the inner wall of the casing satisfying the following formulas (1) and (2) and the rotating body, and the magnetic particles having the resin coating layer A method for producing a carrier for an electrostatic charge image two-component developer, wherein the particles are discharged at a product temperature satisfying the formula (3) .
1.0 <r _max / r _min <5.0 (1)
0.9 <r _max /R<1.0 (2)
(Tg−50 ° C.) <Product temperature (° C.) <Tg (3)
( _Where r _max represents the maximum outer shape of the rotating body, r _min represents the minimum outer shape of the rotating body, R represents the inner diameter of the casing, and Tg represents the glass transition temperature of the resin particles.) In the cooling processing part in the casing, wherein the rotating body has a spiral screw-shaped portion and a kneading-shaped portion to which mechanical shear is applied, and is cooled by the cooling means, the rotating body is at least The method for producing a carrier for an electrostatic charge image two-component developer according to claim 1, comprising a kneading-shaped portion to which mechanical shear is applied. 3. The electrostatic charge image 2 according to claim 1, wherein in the heat treatment part in the casing heated by the heating means, the rotating body has a kneading-shaped portion to which at least mechanical shear is applied. A method for producing a carrier for component developer.

Images