JP2015211953A - Treatment apparatus for covering surface of powder or particle with aggregate of fine particle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a treatment apparatus which is free of restrictions as to the quality and shape of a powder and a fine particle, allows treatment of large amounts of a powder through a single treatment, conducts a treatment at room temperature in the atmospheric air, eliminates the need of a pretreatment of the surface of the powder, does not cause a chemical reaction or a heat treatment or aggregation of particles, with all the requirements combined, and enables a general-purpose powder treatment for covering the surface of a powder in large amounts with aggregate of fine particles at low production costs.SOLUTION: In a treatment apparatus, a cylinder having a mesh filter and a rotor arranged inside the mesh filter are arranged in a container. A pair of rotational flows rotating vertically in mutually opposite directions are circulated between the inside and outside of the cylinder by a rotation centrifugal force of the rotor. Together with the rotational flows, aggregate of a powder is circulated, and aggregate of fine particles is sprayed from a plurality of spraying means onto the powder having passed through the mesh filter of the rotor and the mesh filter of the cylinder.

Description

  In the present invention, a cylinder having a mesh filter at both the upper end and the lower end is installed in a container, and a rotating body is installed inside one of the mesh filters. With the centrifugal force generated by the rotation of the rotating body, the atmosphere in the container is circulated as a pair of swirling flows swirling in the opposite directions in the vertical direction between the inside and outside of the cylinder. With this swirl flow, powder or particles are circulated in the container, and the powder or particles that have passed through the two mesh filters, the mesh filter provided on the rotating body and one of the cylindrical mesh filters, The process of injecting a collection of fine particles from a plurality of injection means is repeated. This is a processing apparatus in which fine particles colliding with the surface of the powder or particles are repeatedly adhered to the surface of the powder or particles by friction, and the surface of the powder or particles is covered with a collection of fine particles.

There are various methods for covering the surface of powder or particles with a collection of fine particles or a new substance. For example, in Patent Document 1, the mother particles and the child particles are charged to different polarities, an electrostatic attraction force is generated between the mother particles and the child particles, and an electrostatic repulsive force is generated between the child particles. A treatment method is disclosed in which the surface is covered with discretely attached child particles.
Patent Document 2 discloses a tin hydroxide in which base particles are dispersed in a mineral acid solution of a hydrolyzable tin compound, and then the pH is increased to hydrolyze the tin compound and precipitate the surface of the base particles. And a method of covering the surface of the base particle with a collection of fine particles of tin oxide deficient in oxygen by firing in an atmosphere in which the oxygen concentration is adjusted.
Further, Patent Document 3 discloses a method in which a group of mother particles covered with a group of child particles is exposed to hot air to melt the child particles and attach a coating made of the material of the child particles to the mother particles. In order to prevent the mother particles from being fused and aggregated by the particles, a processing method is disclosed in which the mother particles heat-treated with hot air are exposed to cold air swirling, and the mother particles are separated and cooled.
Further, Patent Document 4 discloses a treatment method in which iron powder and a silicone resin are mixed and the iron powder is covered with silicone generated by hydrolysis and polymerization reaction of the silicone resin.

  However, the technique described in Patent Document 1 is limited to particles having a property of being charged, and the combination of materials between particles is limited because the mother particles and the child particles are charged with different polarities. Furthermore, since the mother particles and the child particles are charged separately and the charged mother particles and the child particles are mixed, the surface of the mother particles is discretely covered with the child particles in three batch processes, so that the production efficiency is low. . In addition, since the mother particles and the child particles are washed before the charging process to remove impurities that hinder charging, a cleaning and drying pretreatment is required, which increases the manufacturing cost. As described above, a method involving physical treatment such as charging treatment is not a general-purpose method for covering the surface of particles with a collection of fine particles. In addition, since a pretreatment is required instead of a single treatment, the manufacturing cost is high.

  The technique disclosed in Patent Document 2 is limited to a substance that generates a precipitated metal hydroxide substance by hydrolysis. That is, in the case of tin oxide, barium sulfate particles are suspended in water, adjusted to pH 2 with hydrochloric acid, further added with tin tetrachloride solution, stirred, adjusted to pH 11 with sodium hydroxide, Since the tin oxide precipitation material is produced, the materials that can produce the metal hydroxide precipitation material are limited. Thus, the method involving the treatment of chemical reaction such as hydrolysis is not a general-purpose treatment method that covers the surface of the powder or particles with a collection of fine particles.

  The technology disclosed in Patent Document 3 preferentially melts the child particles and solidifies them after melting, so that the mother particles are covered with a coating made of the material of the child particles. Then, since it is limited to a substance that easily solidifies when it comes into contact with cold air, it is not a general treatment method for covering the surface of the mother particle with a coating of a different substance. Furthermore, since the temperature of the hot air is close to the melting temperature of the child particles, if the amount of mother particles covered with the child particles is increased, the temperature unevenness of the mother particles will increase, and the coating made of the material of the child particles will cover it. The rate at which broken mother particles are produced decreases with increasing input. Further, the frequency of contact between the mother particles increases, and the mother particles aggregate. Thus, the processing method involving heat treatment is not suitable for processing a large amount of powder or particles.

  The technique disclosed in Patent Document 4 is limited to a material such as a silicone resin in which an insulating material is generated by hydrolysis and polymerization reaction. As described above, the treatment method involving the treatment of chemical reaction such as hydrolysis and polymerization reaction is not a general treatment method for covering the surface of the powder or particles with a collection of fine particles.

JP-A-9-100189 Japanese Patent Laid-Open No. 11-295914 JP 2004-249206 A JP 2010-183056 A

On the other hand, powders or particles are composed of various materials and shapes, and the material and shape of the fine particles change depending on the application. For this reason, it is difficult to realize a general-purpose processing method for covering the surface of powder or particles with a collection of fine particles. However, if the processing method has the requirements of the following 10 items, it becomes a general-purpose processing method, and a large amount of powder or particles are covered with a collection of fine particles at a low manufacturing cost. First, there is no restriction on the material of the powder or particles and fine particles. Second, there are no restrictions on the shape of the powder or particles and fine particles. Third, a large amount of powder or particles is covered with a collection of fine particles in a single treatment. Fourth, it is a treatment in an air atmosphere. Fifth, treatment at room temperature. Sixth, no pretreatment of the surface of the powder or particles is necessary. Seventh, there is no treatment involving chemical reaction. Eighth, there is no special physical processing. Ninth, no heat treatment is involved. Tenth, no agglomeration or aggregation of powders or particles occurs.
The problem to be solved in the present invention is a treatment that is a general-purpose treatment method that covers the surface of a large amount of powder or particles uniformly with a collection of fine particles at a low production cost, having the above-mentioned requirements for 10 items. To implement the device.

  A first characteristic configuration of a processing apparatus for covering powder or particles according to the present invention with a collection of fine particles is that a container has a cylinder having mesh filters on both the upper end and the lower end, and either one of the meshes. A rotating body, which is arranged inside the filter and includes a rotating shaft in the vertical direction and an umbrella-shaped member having a mesh filter on a side surface which is coupled perpendicularly to the rotating shaft, is installed, and a collection of fine particles is continuously ejected. A plurality of spraying means are processing devices installed at a plurality of locations on the side wall of the container close to the mesh filter of any one of the cylinders, with centrifugal force generated by rotation of the umbrella-shaped member, The atmosphere in the container circulates between the inside and outside of the cylinder as a pair of swirling flows swirling in opposite directions in the vertical direction, and together with the swirling flow, powder or particles are collected. Is circulated in the container, and the process in which the collection of fine particles is sprayed on the powder or particles that have passed through the mesh filter of the umbrella-shaped member and the mesh filter of any one of the cylinders is repeated. Thus, the powder or the surface of the particle is treated with the collection of fine particles.

In other words, according to this characteristic configuration, the air in the container is caused by centrifugal force generated by the rotation of the umbrella-shaped member of the rotating body, and the atmosphere inside the container is swung in the opposite directions in the vertical direction. It circulates as a swirl flow. When powder or a collection of particles is put into the container, the powder or the collection of particles circulates in the container together with the atmosphere. On the other hand, the closer to the rotating umbrella-like member, the more the powder or particles become discrete and floating. When the powder or particles in this state pass continuously through two mesh filters, an umbrella-shaped mesh filter and one of the cylindrical mesh filters arranged nearby, the powder or particles aggregate. Even if it is, aggregation is efficiently released. Immediately after this, a collection of fine particles is ejected from a plurality of ejection means. Such processing is repeated, and the fine particles colliding with the surface of the powder or particles are repeatedly adhered by friction, and the powder or particles are evenly covered with the collection of fine particles.
Therefore, in the present processing apparatus, since the fine particles colliding with the surface of the powder or particles are repeatedly adhered to the surface of the powder or particles by friction, there are no restrictions on the material and shape of the powder or particles and fine particles. In addition, since the treatment is performed once and is performed at room temperature in an air atmosphere, the surface of the powder or particles is covered with a collection of fine particles at a low processing cost. Furthermore, since no pretreatment of the surface of powder or particles is required, no pretreatment that increases the manufacturing cost is required. In addition, since it is a process that only circulates the swirl flow with the centrifugal force when the rotating body rotates, there is no heat treatment, no chemical reaction or special physical treatment, so there is no powder or particles. There are no material restrictions. Furthermore, even if the input amount of powder or particles is increased, the particle size of the powder or particles is increased, or the powder or particles are made of a substance having a high density, If the flow path is extended and the flow velocity of the swirl flow is increased, the powder or particles are covered with a collection of fine particles. Further, since the powder or particles always pass through the three mesh filters in one rotation, the aggregation of the powder or particles can be released.
As described above, this characteristic configuration is a processing method having the requirements of the 10 items described in the 8th paragraph, and since the powder or particles are covered with a collection of fine particles, the surface of the powder or particles is fine. It is a processing apparatus that is a general-purpose processing method that is evenly covered by a gathering.

  The second characteristic configuration of the processing apparatus for covering the powder or particles according to the present invention with a collection of fine particles, the rotating body in the first characteristic configuration described above has a plurality of stirring members composed of a plurality of blades, The plurality of stirring members are rotating bodies attached perpendicularly to the rotation shafts so that the mounting positions of the individual stirring members on the rotation shafts are different from each other.

In other words, according to this characteristic configuration, a plurality of stirring members composed of a plurality of blades are mounted on the rotating body so that the mounting positions of the individual stirring members are different from each other. By rotating the body, a plurality of agitation members composed of a plurality of blades rotate, and a collection of powder or particles in the container floats and circulates in the container in a more discrete state. For this reason, powders or particles are composed of a substance having a high density, or even a powder or a collection of particles having a relatively large particle diameter, or a large amount of powder or particles are filled in the container. However, if the number of blades and the number of stirring members are increased, a collection of powders or particles floats and circulates in the container in a discrete state. Accordingly, even if the powder or particles are aggregated, the aggregation of the powder or particles is easily released when the powder or particles pass through the mesh filter.
Further, if the blades have different lengths in the plurality of stirring members, it is useful for circulating the swirling flow that swirls within the container. In other words, when the umbrella-shaped member of the rotating body is disposed inside the mesh filter at the upper end of the cylinder, the plurality of stirring members can be formed by increasing the length of the blade toward the rotation axis. Since the spiral-shaped new flow is generated by the rotation of the stirring member, it is useful for circulating the swirling flow that swirls in the container. On the other hand, when the umbrella-shaped member of the rotating body is disposed inside the mesh filter at the lower end of the cylinder, the plurality of stirring members may have longer blades as they go below the rotating shaft. As a result, the powder or the collection of particles in the container floats and circulates in the container in a more discrete state.
As described above, since a plurality of stirring members composed of a plurality of blades are attached orthogonally to a plurality of locations of the rotating shaft of the rotating body, powder or particles are composed of a substance having a high density, or Even if it is a powder or a collection of particles with a large particle diameter, or a large amount of powder or particles are filled in the container, the powder or the collection of particles floats in the container in a discrete state. Circulate. Thus, the agglomerated powder or particles are easily released when passing through the mesh filter.

  The third characteristic configuration of the processing apparatus for covering the powder or particles according to the present invention with a collection of fine particles, the cylinder in the first characteristic configuration described above is a plane narrowed in a conical shape having an upper end portion having a mesh filter, The uppermost part is composed of a closed plane, the lower end part is composed of an upside-down conical plane having a mesh filter, and the lowermost part is composed of a closed plane, and the cylinder is in contact with the upper and lower inner surfaces of the container. The umbrella-shaped member of the rotating body in the first characteristic configuration described above is a cylindrical body having an outer shape of a truncated cone shape, a flat surface with the upper part closed, and a lower part opened to the space. The umbrella-shaped member is disposed inside the mesh filter at the upper end of the cylinder.

That is, according to this characteristic configuration, the air in the container is pushed out from the side surface of the umbrella-shaped member to the side surface of the container by the rotational centrifugal force of the umbrella-shaped member. On the other hand, in the lower part of the side surface of the container, the container is drawn inside the cylinder by the rotational centrifugal force of the umbrella-shaped member. As a result, a pair of swirl flows swirling in the opposite directions in the vertical direction between the inside and the outside of the cylinder circulate in the container. Therefore, the powder or particles gathered in the container always passes through the three mesh filters in one turn, and the aggregation of the powders or particles is reliably released. Further, immediately after the powder or particles have passed through the two mesh filters of the side surface of the umbrella-shaped member and the upper end of the cylinder, a collection of fine particles is ejected from a plurality of ejection means, so that aggregation occurs. When the surface of the released powder or particle collides with the fine particle and the fine particle adheres by friction, and these processes are repeated, the surface of the powder or particle is evenly covered with the collection of fine particles.
On the other hand, the speed at which the swirling flow circulates is uniquely determined by the rotational speed of the rotating body, and the rotating speed of the rotating body can be changed according to the density and size of the powder or particles put into the container. For example, the powder or the collection of particles floats and circulates in the container in a state of being separated from each other. In addition, since the size of the flow path through which powder or a collection of particles circulates is uniquely determined by the size of the container and the length of the cylinder, it can be put into the container by changing the size of the container and the length of the cylinder. Even if the amount of the powder or particles to be increased is increased, the powder or the collection of particles floats and circulates in the apparatus while maintaining a discrete state. As a result, a large amount of powder or particles are uniformly covered with a collection of fine particles in a single treatment.

  The fourth characteristic configuration of the processing apparatus for covering powder or particles according to the present invention with a collection of fine particles is that the three mesh filters in the third characteristic configuration described above are the mesh filters at the upper end of the cylinder in the third characteristic configuration. A mesh filter having a finer mesh than that of the other two mesh filters is used.

  That is, according to this characteristic configuration, since the powder or particles always pass through the three mesh filters in one turn, the aggregation of the powder or particles is reliably released. In addition, the mesh filter at the upper end of the inner cylinder has a finer mesh filter than the other two mesh filters. Since the collection of fine particles is jetted, the fine particles adhere to the surface of the powder or particles from which aggregation has been released. When such treatment is repeated, the surface of the powder or particles is uniformly covered with a collection of fine particles.

  The fifth characteristic configuration of the processing apparatus for covering the powder or particles according to the present invention with a collection of fine particles is the cylinder in the first characteristic configuration described above, the upper end portion of which is narrowed into a conical shape having a mesh filter, The uppermost part is composed of a closed plane, the lower end part is composed of an upside-down conical plane having a mesh filter, and the lowermost part is composed of a closed plane, and the cylinder is in contact with the upper and lower inner surfaces of the container. The umbrella member of the rotating body in the first characteristic configuration described above is a cylindrical body whose outer shape is a shape obtained by inverting the truncated cone, the upper part being open to the space, the lower part being closed and the plane being Then, the side surface has a mesh filter, and the umbrella-like member is disposed inside the mesh filter at the lower end of the cylinder.

That is, according to this feature configuration, a pair of swirl flows swirling in opposite directions with respect to the swirl flow in the third feature configuration described above circulates in the container. That is, the air in the container is pushed out to the side surface of the container by the rotational centrifugal force of the umbrella-shaped member. On the other hand, in the upper part of the side surface of the container, it is drawn into the inside of the cylinder by the rotational centrifugal force. As a result, a pair of swirling flows that swirl in the opposite directions in the vertical direction circulate between the inside and the outside of the cylinder. Therefore, as in the third characteristic configuration described above, the powder or particles gathered in the container always passes through the three mesh filters in one swivel, so the powder or particles are surely aggregated. Is released. Further, immediately after the powder or particles pass through the two mesh filters of the side surface of the umbrella-shaped member and the lower end of the cylinder, a collection of fine particles is ejected from a plurality of ejection means, so that aggregation occurs. Fine particles collide with the surface of the released powder or particles, and the fine particles adhere by friction. By repeating such treatment, the surface of the powder or particles is uniformly covered with a collection of fine particles.
On the other hand, the speed at which the swirling flow circulates is uniquely determined by the rotation speed of the rotating body, as in the third feature configuration described above, and the rotation of the rotating body depends on the powder or particle density and particle size. If the speed is changed, the powder or the collection of particles floats and circulates in the apparatus in a state of being separated from each other. Similarly to the third characteristic configuration described above, the size of the flow path through which the powder or particle aggregate circulates is uniquely determined by the size of the container and the length of the cylinder. By changing the size, even if the amount of powder or particles to be added is increased, the powder or the collection of particles floats and circulates in the apparatus while maintaining a discrete state. As a result, a large amount of powder or particles are uniformly covered with a collection of fine particles in a single treatment.

  The sixth characteristic configuration of the processing apparatus for covering powder or particles according to the present invention with a collection of fine particles is that the three mesh filters in the fifth characteristic configuration described above are the mesh filters at the lower end of the cylinder in the fifth characteristic configuration. The mesh filter has a finer mesh than the other two mesh filters.

  In other words, according to this feature configuration, as in the fourth feature configuration described above, the powder or particles always pass through the three mesh filters in one turn, so that the aggregation of the powder or particles is ensured. Canceled. Furthermore, the mesh filter at the bottom end of the cylinder has a finer mesh filter than the other two mesh filters, so the powder or particles that have passed through the finest mesh filter are Since the collection of fine particles is ejected, the fine particles collide with the surface of the powder or particles from which the aggregation has been released and adhere by friction. When such treatment is repeated, the surface of the powder or particles is uniformly covered with a collection of fine particles.

It is a figure explaining the structure of the processing apparatus with which the umbrella-shaped member of the rotary body is arrange | positioned inside the mesh filter of the upper end part of a cylinder. It is a figure explaining the structure of the upper end part of a cylinder. It is a figure explaining the structure of the upper part of a rotary body. It is a figure explaining the structure of the processing apparatus with which the umbrella-shaped member of the rotary body was arrange | positioned inside the mesh filter of the lower end part of a cylinder. It is a figure explaining the structure of the cylinder in the processing apparatus of an Example. It is a figure explaining the arrangement | positioning relationship between the upper end part of a cylinder in the processing apparatus of an Example, and particulate injection means. It is a figure explaining the structure of the upper end part of the rotary body in the processing apparatus of an Example.

Embodiment 1

This embodiment is a first embodiment of a processing apparatus that covers the surface of powder or particles with a collection of fine particles, and a processing apparatus in which an umbrella-like member of a rotating body is arranged inside a mesh filter at the upper end of a cylinder. It is. The overall configuration of the processing apparatus 1 is shown in the plan view of FIG. The processing apparatus 1 includes a container 2, a cylinder 3, a rotating body 4, a motor 5, and a plurality of fine particle injection nozzles 6. The rotating body 4 is provided with four sets of stirring members each having four blades orthogonal to a vertical rotating shaft.
FIG. 2 is a plan view showing the configuration of the upper end portion of the cylinder 3 described above. The upper end portion 30 of the cylinder includes a conical narrowed flat surface 31 having a mesh filter and an uppermost portion 32 formed of a closed flat surface, and the uppermost portion 32 is in contact with the upper surface of the container 2. Although the lower end portion of the cylinder 3 is not shown, like the upper end portion, it is composed of an upside-down conical plane having a mesh filter and a lowermost portion comprising a closed plane, and the lowermost portion is the lower surface of the container 2. Is in contact with
FIG. 3 is a plan view showing the configuration of the upper end portion 40 of the rotating body 4. The upper end portion 40 of the rotator is composed of a conically narrowed plane 41 having a mesh filter, and an uppermost portion 42 formed of a closed plane. It approaches the upper part 32.
When the rotating shaft 43 of the rotating body 4 rotates, the air inside the plane 41 passes through the mesh filter of the plane 41 and the mesh filter of the region 31 due to the centrifugal force generated by the rotation of the plane 41, and the region outside the cylinder 3. Extruded. On the other hand, at the lower end of the cylinder 3, the atmosphere is drawn inside the cylinder 3 by the centrifugal force generated by the rotation of the plane 41. As a result, as indicated by a large arrow in FIG. 1, a pair of swirl flows swirling in the opposite directions in the vertical direction on the outside and inside of the cylinder 3, and the atmosphere circulates inside the container 2.
In the processing apparatus having the above-described configuration, when powder or a collection of particles is put into the container 2, the powder or the collection of particles circulates in the container together with the atmosphere swirling outside and inside the cylinder 3, and the powder The collection of particles is always made in a single turn by the mesh filter on the plane 41 of the rotating body 4, the mesh filter on the plane 31 narrowed in a conical shape at the upper end of the cylinder 3, and the bottom end of the cylinder 3 upside down. Pass through three mesh filters with a flat mesh filter narrowed into a conical shape. On the other hand, the fine particles continuously ejected from the plurality of fine particle injection nozzles 6 are adhered to the powder or particles by friction, and even if the powder or particles are aggregated, the particles are aggregated by passing through the three mesh filters. Canceled. Among other things, since the mesh roughness of the mesh filter of the plane 31 narrowed into a conical shape of the cylinder 3 is composed of a mesh filter having a finer mesh roughness than the mesh roughness of the other two mesh filters, Aggregation of powder or particles is surely released through the mesh filter of the plane 31. Since the fine particles are continuously ejected from the plurality of fine particle injection nozzles 6 to the powder or particles from which the aggregation has been released, the powder or particles do not aggregate through the attached fine particles, and the powder or particles are not aggregated. The surface is evenly covered with fine particles.

Embodiment 2

This embodiment is a second embodiment of a processing apparatus that covers powder or particles with a collection of fine particles, and is a processing apparatus in which an umbrella-like member of a rotating body is arranged inside a mesh filter at the lower end of a cylinder. is there. The overall configuration of the processing apparatus 10 is shown in the plan view of FIG. The configuration of the processing apparatus 10 is such that the rotating umbrella member disposed inside the mesh filter at the upper end of the cylinder shown in FIG. 1 is disposed inside the mesh filter at the lower end of the cylinder in this embodiment. Since the configuration is the same as that of the first embodiment, details of the cylinder and the rotating body are not shown.
In the processing apparatus having such a configuration, when the rotating shaft of the rotating body rotates, the air inside the umbrella-shaped member is caused by centrifugal force generated by the rotation of the umbrella-shaped member, so that the mesh filter of the umbrella-shaped member and the lower end of the cylinder are It is pushed through the mesh filter into the area outside the cylinder. On the other hand, at the upper end of the cylinder, the atmosphere is drawn into the inside of the cylinder by the centrifugal force generated by the rotation of the umbrella-shaped member. As a result, as indicated by arrows in FIG. 4, a pair of swirling flows are formed that swirl outside and inside the cylinder in a direction opposite to the swirling flow illustrated in FIG. 1, and the atmosphere circulates inside the container. To do.
As in the first embodiment, when a powder or a collection of particles is put into the container, the powder or the collection of particles circulates in the container together with the atmosphere swirling between the outside and inside of the cylinder, and the collection of the powder or particles Always passes through three mesh filters: a mesh filter of an umbrella-like member of a rotating body, a mesh filter at the lower end of the cylinder 3, and a mesh filter at the upper end of the cylinder. On the other hand, even if the fine particles sprayed continuously from a plurality of fine particle injection nozzles adhere to the powder or particles by friction and the powder or particles aggregate, the aggregation is released by passing through the three mesh filters. The Above all, since the mesh roughness of the mesh filter at the lower end of the cylinder is configured with finer mesh than the mesh roughness of the other two mesh filters, by passing through the mesh filter at the lower end of the cylinder 3, Aggregation of the powder or particles is reliably released, and the particles or particles are continuously ejected from the plurality of particle injection nozzles to the powder or particles from which the aggregation has been released. The surface of the powder or particles is uniformly covered with fine particles without agglomeration.

First, in four embodiments described below, a processing apparatus that performs processing for covering the surface of powder with a collection of fine particles will be described. The container constituting the apparatus was a cylinder having a diameter of 1 m and a height of 1.5 m, and a cylinder 30 was further arranged inside the container. As shown in the plan view of FIG. 5, the cylinder 30 has a diameter a of 60 cm and a height b of 150 cm, and both the upper and lower ends have a plane 31 and a plane which are constricted with a width c of 20 cm. The upper end surface 32 and the lower end surface 34 are in contact with the upper and lower surfaces of the container. The injection device 60 is arranged on the side wall of the container so that the tip of the injection device 60 is arranged near the flat surface 31 of the upper end portion.
FIG. 6 is a plan view for explaining the positional relationship between the injection device 60 and the plane 31. In the plane 31 having a conical constricted width c of 20 cm, a mesh filter with the finest roughness of the mesh is formed once in a band shape with a width d of 15 cm. The distance e between the spray nozzle 61 and the mesh filter is 5 cm. In addition, 20 injection devices 60 are installed on the side wall of the container at equal intervals with a distance e of 5 cm which is the same as the plane 31. The injection device 60 includes an injection nozzle 61 and a pipe 62. The tip of the pipe 62 is connected to a distributor (not shown), and the tip of the distributor is connected to a pulverizer described later. Accordingly, fine particles finely pulverized by the fine pulverizer are distributed from the fine pulverizer to the 20 pipes 62 by the distributor, and the fine particles are finely divided by the fine pulverizer from the 20 injection nozzles 61 connected to the pipes 62. A collection of fine particles is continuously ejected at a pressure close to the pulverization pressure at the time of pulverization.
FIG. 7 is a plan view for explaining the structure of the upper end portion 40 of the rotating body arranged inside the flat surface 31 of the cylinder 30 constricted in a conical shape. The upper end portion 40 includes an umbrella-shaped body including a flat surface 41 constricted with a width h of 25 cm, an uppermost portion 42 including a closed flat surface, and a rotating shaft 43 coupled to the uppermost portion 42. . The lowermost end of the conical constricted flat surface 41 is a circle having a diameter f of 56 cm, and the uppermost portion 42 is a circle having a diameter g of 20 cm. A mesh filter having the flatest surface roughness 41 having a width h of 20 cm out of 25 cm and the coarsest mesh is formed in a belt shape. Furthermore, 10 pairs of four blades (not shown) are coupled to the rotating shaft 43 at right angles from the distance of 25 cm from the uppermost portion 42 to 10 cm at right angles. The length of the blade is 15 cm, which is the shortest at the lowermost part, and 25 cm, which is the longest at the uppermost part. Furthermore, the rotating shaft 43 is directly connected to a motor arranged at the lower part of a container (not shown), and rotates by operation of the motor.
Four examples will be described below as representative examples using the processing apparatus described above, but examples of covering the surface of the powder with a collection of fine particles are not limited to these four examples. This is because the processing apparatus has the characteristic configuration described in the 10th, 12th, 14th and 16th paragraphs, and is a processing apparatus having the requirements of the 10 items described in the 8th paragraph. This is because the processing apparatus is a general-purpose processing method that is covered with a collection of fine particles.

Using the above-described processing apparatus, the surface of the flaky graphite particles was covered with copper octylate fine particles. As the scaly graphite particles (also referred to as scaly graphite particles), product number CB150 having an average particle diameter of 50 μm and a bulk density of 0.25 Mg / m ³ manufactured by Nippon Graphite Co., Ltd. was used. Further, octyl copper _{Cu (C 7 H 15 COO)} 2 was used the product of Mitsuwa Chemical Industries, Ltd.. The copper octylate was coarsely pulverized and then finely pulverized using a fine pulverizer model NJ-100 called Nano Jet Mizer manufactured by Aisin Nanotechnology Co., Ltd. In this example, 5 kg of copper octylate was supplied to a fine pulverizer at a rate of 5 kg per hour, and pulverized into fine particles having a D50 of 1.2 μm and a D100 of 5 μm by applying a pulverization pressure of 1 MPa. Nanojet Mizer is a jet mill device that accelerates particles with high-pressure gas and pulverizes them by collision between particles, and has a plurality of nozzles that generate concentric swirling vortices by high-pressure jet airflow inside the mill, This is a pulverizing apparatus characterized by suppressing particle temperature rise by the Joule-Thomson effect and having less contamination because the pulverization of particles depends on collisions between particles.
The finely pulverized copper octylate fine particles are supplied from a fine pulverizer to a distributor, further distributed to 20 pipes by the distributor, and further supplied to 20 injection nozzles directly connected to the pipes. Then, copper octylate fine particles were continuously sprayed at a pressure close to 1 MPa as the pulverization pressure. As the injection nozzle, a model 1 / 4M KBN 80 063 TPA CV W called an empty conical nozzle manufactured by Ikeuchi Co., Ltd./fine mist generation minimum injection amount type was used. This injection nozzle has a screw size of 1 / 4M, an injection angle of 80 °, and an injection amount section of 063.
On the other hand, the mesh filter used was a twill weave stainless wire mesh manufactured by Sankyo Wire Mesh Co., Ltd. The mesh filter provided near the injection nozzle and at the upper end of the cylinder is a wire mesh having the finest meshes, and has a wire diameter of 250 μm, a mesh of 50, an opening of 278 μm, and a space ratio of 30%. Next, the mesh filter provided on the side surface of the umbrella-shaped member of the rotating body is a wire mesh having the coarsest mesh, the wire diameter is 340 μm, the mesh is 30, the mesh is 497 μm, and the space ratio is 34%. . The mesh filter provided at the lower end of the cylinder is a wire mesh having intermediate roughness, and has a wire diameter of 290 μm, a mesh of 40, an opening of 345 μm, and a space ratio of 30%.
Using the processing apparatus described above, the surface of the graphite particles was covered with fine particles of copper octylate. First, 9 kg of graphite particles were put into the container, and then the motor was rotated at a rotational speed of 600 rpm, and then the pulverizer was driven under the conditions described above. The graphite particles in the container are circulated by the drive of the motor, and the fine particles of copper octylate are continuously jetted from the jet nozzle by the drive of the fine pulverizer. In this way, a collection of fine particles of copper octylate is sprayed over 20 hours from the 20 spray nozzles to a collection of graphite particles circulating in the container, and after the copper octylate spray is exhausted, the motor is operated for 10 minutes. Was continuously operated, and a collection of graphite particles was circulated in the container to prepare a sample in which the surface of the graphite particles was evenly covered with the fine particles of copper octylate.

Next, the surface of the prepared sample was observed with an electron microscope. As the electron microscope, an extremely low acceleration voltage SEM owned by JFE Techno-Research Corporation was used. This apparatus is capable of observing the surface with an extremely low acceleration voltage from 100 V, and has the feature that the surface of the sample can be observed directly without forming a conductive film on the sample. In addition, when energy between 1 kV and 900 V of the reflected electron beam is extracted and displayed as an image, the difference in material of the material can be understood from the density of the image. Further, when a secondary electron beam between 1 kV and 900 V of the reflected electron beam is taken out and projected as an image, the surface unevenness state can be understood. Furthermore, the substance constituting the surface can be identified by analysis of EDX that reflects the distribution of elements constituting the surface with frequency.
In the image obtained by extracting the energy between 1 kV and 900 V of the reflected electron beam, the entire surface of the graphite particles was shining white. This is a result of the charge up of copper octylate by electrons. Further, in the image obtained by extracting the secondary electron beam between 1 kV and 900 V of the reflected electron beam, the entire surface of the graphite particle was covered with fine particles of 0.6 μm to 5 μm. In the analysis of EDX, the elements constituting the fine particles had the highest precipitation frequency in the order of carbon, oxygen, and copper. From these results, it was found that the entire surface of the graphite particles was covered with fine particles of copper octylate.

  The graphite particles covered with a collection of copper octylate fine particles are thermally decomposed when the temperature is raised from room temperature to near 330 ° C. within 1 minute in the heat treatment in the air atmosphere, and the graphite particles are copper fine particles. Covered with a gathering of. That is, when octyl acid exceeds 228 ° C., which is the boiling point of octylic acid, it is decomposed into octylic acid and copper in a molecular cluster state. When the temperature is further raised, the octylic acid takes the heat of vaporization and vaporizes, and the vaporization of the octylic acid is completed at 290 ° C., a collection of copper fine particles is deposited on the surface of the graphite particles, and the thermal decomposition of the copper octylate is finished. For this reason, in the temperature range from 228 ° C. where the thermal decomposition of copper octylate starts to 290 ° C. where the thermal decomposition of copper octylate is completed, octylic acid vaporizes while continuously taking heat of vaporization on the surface of the graphite particles. To do. On the other hand, octylic acid is a liquid having an ignition point of 371 ° C. Therefore, if vaporization of octylic acid cannot be completed in a short time, octylic acid moves with molecular clustered copper. Therefore, the temperature of the powder or particles is increased from 228 ° C. to 290 ° C. within 10 seconds, and the movement of octylic acid is suppressed, so that the graphite particles are covered with a collection of copper fine particles. On the other hand, since octylic acid ignites at 371 ° C., the temperature cannot be raised to near the ignition point of octylic acid. Furthermore, when the temperature at which the graphite particles are heated to 290 ° C. or higher, the copper fine particles grow by obtaining thermal energy, and the coarsening of the fine particles gradually progresses, and the coarsened particles are deposited at the uneven locations of the graphite particles. To do. As a result, the graphite particles are not covered with a collection of copper fine particles. For this reason, the temperature at which the graphite particles are heated must be suppressed to about 330 ° C. Therefore, when the graphite particles covered with the copper octylate fine particles are heated from room temperature to nearly 330 ° C. within one minute, the graphite particles are covered with a collection of copper fine particles.

  The graphite particles covered with the collection of copper fine particles become a new raw material for a metal graphite brush for a DC motor. This brush has an epoch-making property with no spark discharge, no electrical noise, and a very long operating life. Conventional metal graphite brushes are manufactured by compression-molding a mixture of graphite particles and electrolytic copper powder into a predetermined shape and then firing in a hydrogen gas atmosphere. On the other hand, the novel metal graphite brush is manufactured simply by compression molding the aggregate of graphite particles covered with the aggregate of copper fine particles manufactured in this embodiment into a predetermined shape.

  In the conventional metal graphite brush, the spark discharge phenomenon occurs through the following three steps. First, immediately before the commutator and the brush come into contact with each other, the gap formed between them becomes extremely small, and a large electric field is generated in the gap. This large electric field becomes an electrical load that leads to electrical wear of the graphite particles, spark discharge in the gaps and electrical noise. Second, when a large electric field is applied to the graphite particles, the π electrons of the graphite crystals forming part of the surface layer of the graphite particles are released from the π orbits and become free electrons. The region of the graphite crystal in which π electrons are released from the π orbital is a region where the interlayer bond is broken. This phenomenon is electrical wear. Third, the π electrons, which have become free electrons, gather together to form a lump and sandwich the gap in the direction of the electric field. When this π-electron group wanders through the gap, air molecules are instantaneously excited, causing a light emission phenomenon. This light emission phenomenon is a spark discharge. In addition, electrical noise is generated when air molecules are excited. By taking these three steps, spark discharge is intermittently generated in a very small gap as an instantaneous phenomenon.

A new metallic graphite brush that does not cause spark discharge, does not generate electrical noise, and does not cause electrical wear of the graphite particles may have an equipotential surface. In other words, even if a large electric field acts on the sliding contact surface between the brush and the commutator, if the surface of the graphite particles is an equipotential surface, the free electrons constituting the equipotential surface move in the electric field direction by the Coulomb force due to the electric field. Simply, no electric field acts on the graphite particles inside the equipotential surface. In addition, if the equipotential surface is made of copper, the graphite particles have a resistance value close to that of copper, so that the resistance of the brush can be reduced without mixing electrolytic copper powder as in the past, and the amount of graphite particles used is drastically reduced. Is done.
In graphite particles covered with a collection of copper fine particles, a collection of copper fine particles forms an equipotential surface. Furthermore, the electrical resistance of the graphite particles approaches that of copper. For this reason, the compression molding of graphite particles covered with a collection of copper fine particles is a raw material for a new metal graphite brush that does not cause spark discharge, does not generate electrical noise, and greatly reduces the amount of wear of graphite particles. .

In this example, the glass flake powder was covered with a collection of silver octylate fine particles using the processing apparatus described in paragraph 24. As the glass flake powder, glass flake powder having a product symbol RCF-160 manufactured by Nippon Sheet Glass Co., Ltd. was used. This glass flake powder has an average thickness of 5 μm, a size of 1700 μm to 300 μm is 10% or less, a size of 300 μm to 150 μm is 65% or more, and a 45 μm pass has a particle size distribution of 5% or less, The central particle size is 160 μm. The bulk density is 0.35 Mg / m ³ . Silver octylate Ag (C ₇ H ₁₅ COO) was used as a silver raw material. Since silver octylate is not commercially available, it was newly synthesized by the following production method. Potassium octylate (for example, a product of Toei Chemical Co., Ltd.) and silver nitrate (reagent grade 1 product) were reacted to precipitate silver octylate, and the precipitated silver octylate was washed with water to obtain silver octylate. Similarly to Example 1, the silver octylate was coarsely pulverized and then finely pulverized using a fine pulverizer model NJ-100. In this example, 5 kg of silver octylate finely pulverized at a rate of 5 kg per hour was supplied to a fine pulverizer and pulverized to a D50 of 1.0 μm and a D100 of 4.8 μm by applying a pulverization pressure of 1 MPa. .
The finely pulverized silver octylate is supplied from the fine pulverizer to the distributor as in Example 1, and further distributed to 20 pipes by the distributor, and further to 20 injection nozzles directly connected to the pipes. The fine particles of silver octylate were continuously jetted from 20 jet nozzles at a pressure close to 1 MPa as the grinding pressure. As in the case of Example 1, the injection nozzle used was an empty conical nozzle / a fine mist generation minimal injection amount type.
The mesh filter used was a plain weave stainless steel wire mesh manufactured by Sankyo Wire Mesh Co., Ltd. The mesh filter provided near the injection nozzle and at the upper end of the cylinder is a wire mesh having the finest meshes, having a wire diameter of 210 μm, a mesh of 35, an opening of 515 μm, and a space ratio of 50%. Next, the mesh filter provided on the side surface of the umbrella-shaped member of the rotating body is a wire mesh having the coarsest mesh, the wire diameter is 380 μm, the mesh is 20, the opening is 890 μm, and the space ratio is 49%. . The mesh filter provided at the lower end portion of the cylinder is a wire mesh having intermediate roughness, and has a wire diameter of 570 μm, a mesh of 20, a mesh opening of 700 μm, and a space ratio of 30%.
With the processing apparatus described above, the surface of the glass flake powder was covered with silver octylate fine particles. First, 640 g of glass flake powder was put into the container, and then the motor was rotated at a rotational speed of 1200 rpm, and then the pulverizer was driven under the conditions described above. The glass flake powder in the container circulates by driving the motor, and silver octylate fine particles are continuously sprayed from the spray nozzle by driving the fine pulverizer. In this way, a collection of silver octylate fine particles is sprayed over 20 hours from the 20 spray nozzles to a collection of glass flake powder circulating in the container, and 10 minutes after the silver octylate spray is exhausted. The motor was continuously operated, and a collection of glass flake powder was circulated in the container to prepare a sample in which the surface of the glass flake powder was covered with silver octylate fine particles.

  Next, similarly to Example 1, the surface of the prepared sample was observed with an electron microscope. In the image obtained by extracting the energy between 1 kV and 900 V of the reflected electron beam, the entire surface of the glass flake powder was shining white. This is a result of the charge-up of silver octylate by electrons. Further, in the image obtained by taking out the secondary electron beam between 1 kV and 900 V of the reflected electron beam, the entire surface of the glass flake powder was covered with fine particles of 0.5 μm to 4.8 μm. Further, in the EDX analysis, the elements constituting the fine particles had the highest precipitation frequency in the order of carbon, oxygen, and silver. From these results, it was found that the glass flake powder was evenly covered with silver octylate fine particles.

  When the glass flake powder covered with the silver octylate fine particles produced in this example was heated from room temperature to near 330 ° C. within 1 minute in the heat treatment in the air atmosphere, the silver octylate was thermally decomposed, and the glass flakes The powder is covered with a collection of silver particles. That is, like the copper octylate of Example 1, since silver octylate is an octylic acid metal compound, when it exceeds 228 degreeC which is a boiling point of octylic acid, it will decompose | disassemble into octylic acid and silver of a molecular cluster state. When the temperature is further raised, octylic acid takes the heat of vaporization and vaporizes, and the vaporization of octylic acid is completed at 290 ° C., a collection of silver fine particles is deposited on the surface of the glass flake powder, and the thermal decomposition of silver octylate is completed. For this reason, in the temperature range from 228 ° C. where the thermal decomposition of silver octylate starts to 290 ° C. where the thermal decomposition of silver octylate is completed, octylic acid continuously takes heat of vaporization on the surface of the glass flake powder. Vaporize. Octyl acid is a liquid having an ignition point of 371 ° C. Therefore, if the vaporization of octylic acid cannot be completed in a short time, octylic acid moves with molecular clustered silver. Therefore, the powder or particles are heated from 228 ° C. to 290 ° C. within 10 seconds, and the movement of octylic acid is suppressed, so that the glass flake powder is covered with a collection of silver fine particles. On the other hand, since octylic acid ignites at 371 ° C., the temperature cannot be raised to near the ignition point of octylic acid. Further, when the temperature at which the glass flake powder is heated is 290 ° C. or higher, the silver fine particles grow by obtaining thermal energy, and the coarsening of the fine particles gradually proceeds, where the coarsened particles are unevenly distributed in the glass flake powder. It precipitates in. As a result, the glass flake powder is not covered with a collection of silver fine particles. For this reason, the temperature at which the glass flake powder is heated must be suppressed to about 330 ° C. Therefore, when the glass flake powder covered with the silver octylate fine particles is heated from room temperature to nearly 330 ° C. within 1 minute, the glass flake powder is covered with a collection of silver fine particles.

Glass flake powder covered with a collection of silver fine particles is a glass flake with the property of silver that has the highest thermal conductivity and electrical conductivity among metal elements and has the highest reflectivity in all visible light region. It becomes powder. For this reason, glass flake powder can be used as a conductive filler of a conductive paste.
Further, since the glass flake powder is covered with nano-sized silver fine particles, the surface is formed with nano-sized irregularities, hardly emits white light, and emits a metallic luster with excellent saturation. Further, when the thickness of the silver fine particles is set to a thickness corresponding to the wavelength of the individual color tone of visible light, the reflected light on the surface of the silver fine particles and the reflected light on the surface of the glass flakes are interfered with each other and amplified. The individual color tone is a relatively strong reflected light. As a result, the glass flake powder can be used as a pigment for paints that emits a metallic luster with excellent saturation with a relatively strong individual color tone of visible light.

In this example, the surface of the flat iron powder was covered with fine particles of iron naphthenate using the processing apparatus described in paragraph 24. The flat iron powder is obtained by flattening reduced iron powder, and flat iron powder MG150D manufactured by JFE Steel Corporation was used. This flat iron powder has a bulk density of 1.50 Mg / m ³ and a particle size distribution of 14% in a path of 45 μm, 45% to 63 μm is 12%, 63 μm to 75 μm is 6%, and 75 μm to 106 μm is 24%. 106 μm to 150 μm is 42%, and 150 μm to 180 μm is 2%. The (compounds with more saturated fatty acids and iron with a 5-membered ring) iron naphthenate _{Fe (C n H 2n-1} COO) 2 was used the product of Toei Chemical Corporation. The iron naphthenate was finely pulverized after coarse pulverization using a fine pulverizer model NJ-100 in the same manner as copper octylate described in paragraph 25. In this example, 2.6 kg of iron naphthenate finely pulverized at a rate of 3 kg per hour is supplied to a fine pulverizer and pulverized as fine particles having a D50 of 0.9 μm and a D100 of 5 μm by applying a pulverization pressure of 1 MPa. did.
Finely pulverized iron naphthenate is supplied from a fine pulverizer to a distributor, further distributed to 20 pipes by the distributor, and further supplied to 20 injection nozzles directly connected to the pipes, and then pulverized from the injection nozzles. Fine particles of iron naphthenate were continuously jetted at a pressure close to 1 MPa. As the injection nozzle, an empty conical nozzle / a fine mist generating minimum injection amount form was used in the same manner as the copper octylate described in the 25th paragraph.
On the other hand, the mesh filter used was a plain weave stainless steel wire mesh manufactured by Sankyo Wire Mesh Co., Ltd. The mesh filter provided near the injection nozzle and at the upper end of the cylinder is a wire mesh having the finest mesh, has a wire diameter of 260 μm, a mesh of 40, an opening of 375 μm, and a space ratio of 35%. Next, the mesh filter provided on the side surface of the umbrella-shaped member of the rotating body is a wire mesh with the coarsest mesh, the wire diameter is 290 μm, the mesh is 24, the opening is 768 μm, and the space ratio is 53%. . The mesh filter provided at the lower end of the cylinder is a wire mesh having intermediate roughness, and has a wire diameter of 280 μm, a mesh of 30, a mesh opening of 566 μm, and a porosity of 45%.
By the processing apparatus described above, the surface of the flat iron powder was covered with fine particles of iron naphthenate. First, 150 g of flat iron powder was put into the container, and then the motor was rotated at a rotational speed of 1800 rpm, and the pulverizer was driven under the conditions described above. The flat iron powder in the container circulates by driving the motor, and fine particles of iron naphthenate are continuously jetted from the jet nozzle by driving the fine pulverizer. In this way, a collection of flat iron powder circulating in the container is sprayed with a collection of iron naphthenate fine particles from 20 injection nozzles for 50 minutes, and after the iron naphthenate injection is exhausted, the motor is run for 10 minutes. The sample was continuously operated and a collection of flat iron powder was circulated in the container to prepare a sample in which the surface of the flat iron powder was covered with fine particles of iron naphthenate.

  Next, the surface of the prepared sample was observed using an electron microscope as in the 26th paragraph. In the image obtained by extracting the energy between 1 kV and 900 V of the reflected electron beam, the entire surface of the flat iron powder was shining white. This is a result of the iron naphthenate being charged up by electrons. Furthermore, in the image obtained by extracting the secondary electron beam between 1 kV and 900 V of the reflected electron beam, the entire surface of the graphite particle was covered with fine particles of 0.5 μm to 5 μm. Moreover, from the analysis result of EDX, the element which comprises microparticles | fine-particles had the high precipitation frequency in order of carbon, oxygen, and iron. From these analysis results, it was found that the entire surface of the flat iron powder was covered with fine particles of iron naphthenate.

  The flat iron powder covered with the fine particles of iron naphthenate produced in this example was heated from room temperature to near 330 ° C. within 90 seconds in the heat treatment in the air atmosphere. The powder is covered with a collection of fine particles of iron (II) oxide. In other words, iron naphthenate is a compound of iron and a plurality of saturated fatty acids having a five-membered ring. When flat iron powder covered with iron naphthenate fine particles is heat-treated in the air, the saturated fatty acid that forms naphthenic acid When the temperature exceeds 240 ° C. which is the boiling point of the saturated fatty acid having the highest boiling point, iron naphthenate is thermally decomposed into naphthenic acid and molecular cluster iron (II) FeO. When the temperature is further increased, the naphthenic acid is vaporized by removing the heat of vaporization, vaporization of the naphthenic acid is completed at 310 ° C., and a collection of iron (II) oxide fine particles is deposited on the surface of the flat iron powder. Finish pyrolysis. For this reason, in the temperature range from 240 ° C. to 310 ° C. where the thermal decomposition is completed, naphthenic acid continuously takes the heat of vaporization and vaporizes on the surface of the flat iron powder. However, since naphthenic acid is a liquid, if vaporization of naphthenic acid cannot be completed in a short time, naphthenic acid moves with molecular cluster-like iron oxide (II). For this reason, it is necessary to raise the temperature of the powder or particles from 240 ° C. to 310 ° C. within 20 seconds to suppress the movement of naphthenic acid. Therefore, when the flat iron powder covered with the fine particles of iron naphthenate is heated from room temperature to nearly 330 ° C. within 90 seconds, the flat iron powder is covered with a collection of fine particles of iron (II) oxide.

The flat iron powder covered with a collection of fine particles of iron (II) FeO is controlled at a rate of temperature rise in the air atmosphere, that is, 3 (II) Fe ^{2+ of} iron (II) FeO divalent iron ions are ^added. When the oxidation reaction to become a valent iron ion Fe ³⁺ is gradually advanced and left at a temperature of about 390 ° C., the divalent iron ion Fe ^{2+ of} iron (II) FeO is oxidized and the trivalent iron ion Fe ³⁺ is oxidized. Thus, iron (II) FeO becomes maghemite γ-Fe ₂ O ₃ which is the γ phase of iron (III) Fe ₂ O ₃ . For example, 20 ° C./min. The temperature was increased to 300 ° C. at a rate of temperature increase of 300 ° C., and thereafter from 300 ° C. to 1 ° C./min. The temperature is raised to 390 ° C. at a speed of 390 ° C. and left at 390 ° C. for 30 minutes. Maghemite γ-Fe ₂ O ₃ is a ferromagnetic and insulating oxide. As a result, the surface of the flat iron powder is insulated by the collection of maghemite fine particles, and becomes a suitable raw material for the dust core.

That is, first, since maghemite is an insulating material having a specific resistance of 10 ⁶ Ωm, the flat iron powder covered with maghemite fine particles becomes an insulator. Since the specific resistance of iron is 10 ⁻⁷ Ωm and the eddy current loss of iron powder is inversely proportional to the specific resistance, the eddy current loss of insulated iron powder is significantly reduced. Secondly, the maghemite having spontaneous magnetization is magnetically adsorbed to the iron powder, and even if an excessive pressure is applied during compression molding of the iron powder, the magnetically adsorbed maghemite fine particles are fine particles and thus do not peel off from the iron powder. Thereby, the insulation of the iron powder after compression molding is maintained. In addition, no pretreatment of iron powder for forming the insulating layer is required. Third, it transitions to hematite around 450 ° C. For this reason, when magnetic annealing of the compact is performed at a temperature of 450 ° C. or higher, maghemite undergoes phase transition to hematite. This phase transition is an irreversible change. Hematite is a substance having a specific resistance of 10 ⁷ Ωm, and annealing improves the insulation of iron powder by an order of magnitude and further reduces eddy current loss. Hematite is a stable oxide, that is, passive, and has heat resistance close to the melting point of 1566 ° C. For this reason, the properties of hematite are not changed by magnetic annealing at 600 ° C. or higher. Further, the diffusion phenomenon at the interface with the iron powder does not occur during annealing, and the iron powder does not deteriorate. Incidentally, the melting point of iron is 1535 ° C. Hematite has a chemical formula of α-Fe ₂ O ₃ , is an α phase of iron (III) Fe ₂ O ₃ , has weak ferromagnetism, and has a magnetic Curie point of 950 ° C. Fourth, the Mohs hardness is 5.5, which is a material harder than iron or iron-based alloys. For this reason, even if pressure is applied during compression molding, the maghemite fine particles are not destroyed. That is, at the time of compression molding, the maghemite fine particles maintain a magnetically adsorbed state, and in this state, iron powder having a lower hardness than maghemite preferentially undergoes plastic deformation. As a result, the iron powders are intertwined and the iron powders are combined. At this time, the surface of the iron powder is kept insulative by the maghemite fine particles, and the magnetic flux density and the mechanical strength of the dust core increase as the density of the compact increases.
The raw material of the powder magnetic core is not limited to the flat iron powder obtained by flattening reduced iron powder, but may be a magnetic powder obtained by flattening atomized pure iron powder or atomized alloy powder.

In this example, the surface of the iron oxide powder was covered with fine gold complex salt particles using the processing apparatus described in paragraph 24. The iron oxide powder is an α phase of iron (III) Fe ₂ O ₃ and is called hematite or red iron oxide. The melting point is as high as 1566 ° C., and it is an extremely stable oxide. It is an electrical insulator and has a weak magnetism of weak ferromagnetism. The powder is reddish brown and is known as red rust or petal. AM-200 manufactured by Titanium Industry Co., Ltd. was used as the iron oxide powder. This iron oxide powder has a refractive index of light close to 3, a specific surface area of 1.5 to 2.2 m ² / g, a particle diameter of 2 to 50 μm, an average particle diameter of 12 to 15 μm, and an average particle thickness. Is as thin as 0.2 to 0.3 μm, and the bulk density is 0.3 to 0.4 g / cm ³ .
On the other hand, as the gold complex salt, hydrogen tetrachloroaurate (III) H [Au (Cl) ₄ ] was used. Tetrachloro gold complex ion in which a chloride ion Cl ⁻ serves as a ligand and coordinates to gold ion Au ³⁺ among a gold complex ion in which a ligand composed of an inorganic molecule or ion is coordinated to gold ion [Au (Cl) ₄ ] ⁻ is the most easily synthesized gold complex ion. Furthermore, tetrachlorogold (III) hydrogen tetrahydrate H [Au (Cl) ₄ ] · 4H ₂ O can be obtained by simply dissolving gold in aqua regia or by converting gold (III) chloride AuCl ₃ into hydrochloric acid. It can be easily synthesized simply by melting and crystallizing. In addition, since it is the inorganic salt with the smallest molecular weight, when it is heat-treated in a reducing atmosphere such as ammonia gas or hydrogen gas, the coordination bond site is first divided and decomposed into metal and inorganic matter, and the molecular weight of the inorganic matter is small. The vaporization of the inorganic substance is completed at a temperature as low as about 200 ° C., and gold is deposited. Tetrachlorogold (III) oxyhydrogen tetrahydrate was a product of Wako Pure Chemical Industries, Ltd. Tetrachlorogold (III) hydrogen tetrahydrate was coarsely pulverized and then finely pulverized using a fine pulverizer NJ-100 in the same manner as copper octylate described in paragraph 25. In this example, 1.1 kg of tetrachloroauric (III) hydrogen tetrahydrate pulverized at a rate of 1.5 kg per hour was supplied to a pulverizer, and a pulverization pressure of 1 MPa was applied to obtain D50. Was finely pulverized as fine particles having a diameter of 1.0 μm and D100 of 4.8 μm.
Finely pulverized tetrachlorogold (III) oxyhydrogen is supplied from a fine pulverizer to a distributor, further distributed to 20 pipes by a distributor, and further supplied to 20 injection nozzles directly connected to the pipes. The fine particles were continuously jetted from the jet nozzle at a pressure close to 1 MPa as the pulverization pressure. As the injection nozzle, an empty conical nozzle / a fine mist generating minimum injection amount form was used in the same manner as the copper octylate described in the 25th paragraph.
The mesh filter used was a twill weave stainless wire mesh manufactured by Sankyo Wire Mesh Co., Ltd. The mesh filter provided near the injection nozzle and at the upper end of the cylinder is a wire mesh having the finest meshes, has a wire diameter of 60 μm, a mesh of 190, an opening of 73 μm, and a porosity of 29%. Next, the mesh filter provided on the side surface of the umbrella-shaped member of the rotating body is a wire mesh having the coarsest mesh, a wire diameter of 230 μm, a mesh of 60, an opening of 193 μm, and a space ratio of 21%. . The mesh filter provided at the lower end of the cylinder is a wire mesh having intermediate roughness, and has a wire diameter of 120 μm, a mesh of 100, an opening of 134 μm, and a space ratio of 28%.
With the processing apparatus described above, the surface of the iron oxide powder was covered with fine particles of tetrachloroauric (III) hydrogen hydride tetrahydrate. First, 6.4 kg of iron oxide powder was put into the container, the motor was rotated at a rotational speed of 900 rpm, and the fine pulverizer was driven under the conditions described above. The iron oxide powder in the container is circulated by driving the motor, and fine particles of tetrachloroauric (III) hydrogen oxyhydrogen tetrahydrate are continuously jetted from the jet nozzle by driving the fine pulverizer. Thus, a collection of fine particles of tetrachloroauric (III) hydrogen oxyhydrogen tetrahydrate is sprayed from the 20 spray nozzles to the collection of iron oxide powder circulating in the container for 45 minutes, and the spray of fine particles is depleted. After that, the motor was continuously operated for 10 minutes to circulate the iron oxide powder in the container, and the surface of the iron oxide powder was covered with fine particles of tetrachloroauric (III) hydrogen hydride tetrahydrate. A sample was prepared.

  Next, the surface of the prepared sample was observed using an electron microscope as in the 26th paragraph. In the image obtained by extracting the energy between 1 kV and 900 V of the reflected electron beam, the entire surface of the iron oxide powder was shining white. This is a result of charging up the hydrogen of tetrachloroaurate (III) with electrons. Further, in the image obtained by extracting the secondary electron beam between 1 kV and 900 V of the reflected electron beam, the entire surface of the graphite particle was covered with fine particles of 0.5 μm to 4.8 μm. Moreover, from the analysis result of EDX, the element which comprises microparticles | fine-particles had the high precipitation frequency in order of chlorine, oxygen, and gold | metal | money. From these results, it was found that the iron oxide powder was covered with fine particles of tetrachloroauric (III) hydrogen hydride tetrahydrate.

When the iron oxide powder covered with the fine particles of tetrachlorogold (III) oxyhydrogen H [Au (Cl) ₄ ] is heated to a temperature of about 200 ° C. composed of a reducing atmosphere such as hydrogen gas or ammonia gas. Then, tetrachlorogold (III) oxyhydrogen H [Au (Cl) ₄ ] is reduced, and the iron oxide powder is covered with gold fine particles.
Since the iron oxide powder is covered with gold fine particles having a nano size, there is almost no white scattering of light, and it emits a brilliant brightness. Further, when the thickness of the gold fine particle is a thickness corresponding to the wavelength of the individual color tone of visible light, the reflected light on the surface of the gold fine particle and the reflected light on the surface of the iron oxide powder are amplified by interference with each other, The individual colors of visible light are reflected light that is relatively strong. As a result, the iron oxide powder can be used as a pigment for paints that emits metallic luster with excellent color saturation in which the individual shades of visible light are mixed with the reddish brown color of the iron oxide powder.

In the above, four embodiments have been described in which the surface of the powder is covered with a collection of fine particles using the processing apparatus according to the present invention. However, examples of covering the surface of the powder with a collection of fine particles are not limited thereto. This is because, firstly, the fine particles colliding with the surface of the powder repeatedly adhere to the surface of the powder by friction, so there is no restriction on the material and shape of the powder and fine particles. Second, since the treatment is performed at room temperature in an air atmosphere, there are no restrictions on the material of the powder and fine particles. Third, since powder and fine particles need no surface pretreatment, there is no restriction on the material of the powder and fine particles. Fourth, there is no restriction on the material of the powder because it is a process that only circulates the swirling flow generated by the centrifugal force generated when the rotating body rotates. Fifth, since there is no heat treatment, even if the amount of powder input is increased, or even if the particle size of the powder is relatively large or the bulk density of the powder is large, swirling If the flow path is extended and the flow velocity of the swirl flow is increased, a large amount of powder is covered with a collection of fine particles. Sixth, since the powder repeatedly passes through the three mesh filters, the aggregation of the powder or particles can be released.
Therefore, the present invention has no restrictions on the material and shape of the powder or particles and fine particles, and the powder or particles covered with the collection of fine particles can be produced in large quantities at a low production cost. The processing apparatus according to the present invention can be used for a wide range of applications including new applications as well as applications. For this reason, the processing apparatus for covering the powder or particles according to the present invention with a collection of fine particles is a general purpose in which the surface of the powder or particles made of various materials and shapes is covered with the collection of fine particles made of various materials and shapes. This is a processing apparatus that is a typical processing method.

  DESCRIPTION OF SYMBOLS 1 thru | or 10 Processing apparatus 2 Container 3 thru | or 30 Cylinder 31 Side surface of upper end part of cylinder 32 Uppermost part of upper end part of cylinder 33 Side surface of lower end part of cylinder 34 Lowermost part of lower end part of cylinder 4 Rotating body 40 Umbrella-shaped member 41 Umbrella Side surface 42 of the member-like member Upper end portion of the umbrella-like member 43 Rotating shaft 5 Motor 6 or 60 Particulate injection device 61 Injection nozzle 62 Pipe

Claims (6)

A processing apparatus that performs processing to cover the surface of powder or particles with a collection of fine particles,
Inside the container, a cylinder having a mesh filter on both the upper end and the lower end, and a side surface that is disposed inside one of the mesh filters and is coupled perpendicularly to the vertical rotation axis. A rotating body made of an umbrella-shaped member having a mesh filter is installed on the side wall of the container near the mesh filter of one of the cylinders. And a pair of swirling flows in which the atmosphere in the container swirls in an up and down direction in opposite directions by centrifugal force generated by the rotation of the umbrella-shaped member. Circulate and circulate a powder or a collection of particles together with the swirl flow in the container, and the mesh filter of the umbrella-shaped member and the mesh of any one of the cylinders The powder or particles that have passed through the filter are repeatedly subjected to the process of spraying the collection of fine particles, whereby the surface of the powder or particles is covered with the collection of fine particles. It is the processing apparatus characterized.   The rotating body according to claim 1 has a plurality of stirring members composed of a plurality of blades, and the plurality of stirring members rotate in such a manner that mounting positions of the individual stirring members on the rotation shafts are different from each other. The rotating body according to claim 1, wherein the rotating body is attached perpendicular to the axis.   The cylinder according to claim 1 is composed of a plane narrowed in a conical shape having an upper end portion having a mesh filter and a plane closed in an uppermost portion, and a plane narrowed in an inverted conical shape having a lower end portion having a mesh filter. And the cylindrical part is disposed in contact with the upper and lower inner surfaces of the container, and the umbrella-shaped member of the rotating body according to claim 1 has a truncated cone shape. A cylindrical body having a closed upper surface, a lower portion opened to a space, a mesh filter on a side surface, and the umbrella-shaped member disposed inside the mesh filter at the upper end of the cylinder. The umbrella-shaped member of the cylinder and the rotary body according to claim 1, wherein   The three mesh filters in claim 3 are configured by a mesh filter in which the mesh filter of the upper end of the cylinder in claim 3 is finer than the mesh sizes of the other two mesh filters. The three mesh filters according to claim 3.   The cylinder according to claim 1 is composed of a plane narrowed in a conical shape having an upper end portion having a mesh filter and a plane closed in an uppermost portion, and a plane narrowed in an inverted conical shape having a lower end portion having a mesh filter. And the bottom part of the umbrella-shaped member of the rotating body according to claim 1 is arranged upside down on the truncated cone. A cylindrical body having an upper shape open to a space, a lower portion is closed and a flat surface, and a mesh filter is provided on a side surface, and the umbrella-shaped member is disposed inside the mesh filter at the lower end of the cylinder. The cylindrical and rotating umbrella-shaped member according to claim 1, wherein   The three mesh filters according to claim 5 are characterized in that the mesh filter at the lower end of the cylinder according to claim 5 is composed of a mesh filter finer than the mesh roughness of the other two mesh filters. The three mesh filters according to claim 5.

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