JP2005015910A - Method for manufacturing composite particle, and composite particle manufactured thereby - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently obtain a composite particle having an adequate composite film and a coating layer, even on fine powder particles. <P>SOLUTION: This method for manufacturing the composite particle having various characteristics by combining physically different materials includes simultaneously giving a compressive force and a shearing force to an article to be processed 4, which is a mixture of base-particles as nuclei and sub-particles finer than them, to fix the sub-particles or form the coating layer of the sub-particles on the surfaces of the base-particles. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for producing composite particles that are also used as new material materials in powder metallurgy, ceramics, toner, powder paint, hybrid resin, secondary battery, and other various industrial fields.

  Conventionally, as a method of coating the surface of the particles with another substance, the solution and the fine particles suspended in the solution are spray-dried as a solution, or the solution or suspension solution is spray-mixed to the powder particles that are fluidized or stirred and dispersed. The particles are collided at high speeds using air or fluid flow, such as the impact force of a ball mill and a mechanical impact pulverizer, or a jet mill that pulverizes by mixing and mixing media such as pulverized balls and beads. For example, there is a method in which mechanical energy is applied to fix the child particles on the surface of the mother particle (for example, see Patent Document 1).

  In addition, it is based on mechanical energy, and it has been conventionally performed at the laboratory stage to form composite particles of metal powder and ceramic powder as raw materials for powder metallurgy using a ball mill or mortar.

Japanese Patent Publication No. 3-2009

  However, in these methods, the particle size of the core particle, for example, several tens of microns, is smaller than the particle size of the child particle of several microns. When the particle size of the child particle is 1 μm or less, the desired size is obtained. Could not be manufactured.

  In view of this point, an object of the present invention is to efficiently obtain composite particles having a fine composite film and a coating layer even if they are fine powder particles.

  In the method for producing composite particles according to the first aspect of the present invention, two or more kinds of powdery materials are placed in a mixed state, and the core particles serving as nuclei and finer child particles are compressed in the mixed state. By applying a shearing force, the child particles are fixed on the surface of the mother particles or a coating layer of the child particles is formed to be combined.

  In order to carry out the present invention, a desired product can be efficiently obtained by using a powder processing apparatus as shown in FIGS. 1 and 2, for example. The powder processing apparatus of FIG. 1 normally performs batch operation, and is configured to supply raw materials and discharge processed products every time, and does not take out products during operation. In the powder processing apparatus shown in FIG. 2, the processed product can be discharged together with the supply of the raw material, and the continuous operation can be performed.

  [Function and Effect] The method for producing composite particles according to the first invention is to form composite particles by a composite treatment. The compounding process refers to a process in which a compression force and a shearing force are applied to a mixture of a plurality of raw materials so that other raw materials are fused and integrated on the surface of a specific raw material. Thereby, the distribution of each material becomes uniform, and composite particles having a coating film and a coating layer of uniform components can be obtained. Moreover, the combination according to various materials and shapes can be performed by adding temperature control to the said process process. Further, since the binder component is not mixed into the composite particles as in the case where the child particles are sprayed as a suspension, it is possible to provide a material that has less influence on the next process.

  The method for producing composite particles according to the second invention limits the preferred conditions of the method for producing composite particles according to the first invention, wherein the mother particles have a particle size of 10 nm or more and the child particles have a particle size of 1 μm or less and the particle size ratio of the mother particles to the child particles is 10 or more. That is, even if the particle size of the mother particle is 10 nm or more and the particle size of the child particle is 1 μm or less, if the particle size ratio of the mother particle to the child particle is 10 or more, a good composite is possible. If it is 100 or more, it can be combined more satisfactorily.

  [Function and effect] In the formation of the composite particles of the present invention, the mother particles as the core and the small child particles are mixed to apply the compressive force and shear force, but the mixing action is promoted even at the stage of applying the compressive force and shear force. As a result, it is possible to suppress the agglomeration of the two and precisely mix them, and even if the particle size is 1 μm or less, for example, about 1 nm, it is possible to promote contact adhesion with the mother particle and make it complex. be able to. Here, the precision mixing means mixing different kinds of raw materials in a state of being uniformly dispersed at a single particle level.

  The composite particle according to the third invention is a composite particle produced by the method for producing a composite particle according to the first or second invention, and the child particle is fixed on the surface of the mother particle or a coating layer of the child particle is formed. The composite particles produced by combining the core particles and the fine child particles are uniformly mixed and simultaneously applied with compressive force and shear force. Are uniformly distributed and uniformly pressed and firmly fixed on the surface of the mother particle by a strong compressive force and shear force.

  [Function and Effect] The composite particles according to the present invention are fine composite particles having a mother particle as a core and a homogeneous and strong film or coating layer of the child particles, and the mother particles and the child particles are inorganic, organic, metal, and Since various materials can be applied to liquid materials as well as powder materials, it is possible to provide an optimal composite material adapted to the intended purpose and application.

  Further, the composite particles of the present invention do not mix the binder component into the composite particles as in the case of spraying the child particles as the coating material as a suspension, so that the composite particles can be used as raw materials and products such as foods and pharmaceutical preparations. The field of use can be expanded. In addition, it is not necessary to add a solution, a binder, or the like in the case of compounding, but a binder may be added as necessary when it is desired to increase the strength.

  The method for producing composite particles according to the fourth invention is an applied invention based on the method for producing composite particles according to the first or second invention. In other words, the core particle as a core is made of a molten or soluble material, and the child particle is fixed on the surface of the mother particle by applying a compressive force and a shearing force in a mixed state of the mother particle and a child particle finer than that. Alternatively, a composite particle is manufactured by forming a coating layer of child particles, and then only the mother particle component is melted or dissolved and removed from the composite particle to make it hollow, and a molten or soluble material is used for the mother particle. It is possible by doing.

  [Effect] The hollow composite particles according to the present invention are formed into hollow particles when the core particle portion that is the core of the composite particles is not melted and evaporated or eluted. It can be easily implemented by using excellent materials. When the mother particle component is melted and removed, a material having low heat melting property and less generation of unnecessary gas or the like is preferable. When the mother particle component is dissolved and removed, it is important to select a material that is easily dissolved in the solvent. In order to promote melting and melting, it is necessary to control the pressure and temperature in the furnace and the processing chamber.

  The composite particle according to the fifth invention is a hollow composite particle manufactured by the method for manufacturing a composite particle according to the fourth invention, and various combinations including selection of the material of the mother particle and the child particle are conceivable. The use of new materials in the development field is expected.

  As described above, according to the present invention, it is possible to efficiently produce composite particles in which a child particle is fixed on the surface of a mother particle serving as a nucleus or a coating layer of the child particle is formed, and fine particles of submicron or less are produced. Composite particles having a composite coating and a coating layer of various powder particles can be obtained.

  Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 schematically show a powder processing apparatus used in the present invention. 3 to 14 show composite particles produced by the practice of the present invention.

  (Powder Processing Apparatus) The powder processing apparatus in FIG. 1 mainly includes a substantially cylindrical casing 2 installed on a base 1 and a cylindrical rotating body having a substantially cylindrical shape provided inside the casing 2. 3 and a press head 5 disposed inside the cylindrical rotating body 3 for generating a pressing force between the cylindrical rotating body 3 and processing the workpiece 4. By rotating the cylindrical rotating body 3, the receiving surface 6 formed on the inner peripheral surface of the cylindrical rotating body 3 and the press head 5 are relatively rotated, and the receiving surface 6 and the press head 5 are A compression force and a shearing force are applied to the workpiece 4 existing in the space 7 between them, and as described above, the raw materials are combined, mixed, spheroidized, and the like. In the present invention, these processes are collectively called mechanofusion processes.

  The workpiece 4 to which the compressive force and the shearing force are applied by the press head 5 is discharged outwardly mainly through a hole 9 provided in the peripheral wall 8 of the cylindrical rotating body 3, and the peripheral wall 8 It is made to circulate again inside the said cylindrical rotary body 3 by the blade member 10 formed in the outer peripheral part. By adopting this configuration, the workpiece 4 sandwiched between the press head and the receiving surface 6 can be actively flowed and circulated to reduce the amount of the workpiece 4 attached to the receiving surface 6. it can. Depending on the type of material to be treated, physical properties may be impaired when an excessive compressive force or shear force is applied. However, if an apparatus configured to circulate the workpiece 4 through the hole 9 as in the powder processing apparatus is used, the compressive force applied to the workpiece 4 can be appropriately adjusted. . For example, if the opening area of the hole 9 is set wide, the workpiece 4 is easily discharged to the outside of the cylindrical rotating body 3, so that the operation time of the press head 5 on the workpiece 4 is short. As a result, the compressive force or the like acting on the workpiece 4 is weakened as a result. On the contrary, if the opening area of the hole 9 is set to be narrow, the operation time of the press head 5 with respect to the object to be processed 4 becomes longer, and the compression force and the like become stronger. Thus, when using the powder processing apparatus of this structure, it is possible to obtain the optimum powder processing conditions by arbitrarily changing the compressive force or the like that acts on the object 4 to be processed. You can get a product.

  Depending on the material to be processed, the inside of the powder processing apparatus may be depressurized or a predetermined gas atmosphere. Therefore, in the powder processing apparatus according to the present invention, for example, the seal member 11a, between the casing 2 and the shaft body 3a of the cylindrical rotating body 3 or between the casing 2 and the support rod 5a of the press head 5 is provided. 11b is provided.

  The powder processing apparatus shown in FIG. 2 is capable of continuous processing, and is a press supported by a rotary shaft 20 in a lateral direction with respect to a casing 22 of a horizontal long barrel fixed to a machine base (not shown). A plurality of heads 25 are arranged in a plurality of rows on the outer peripheral portion of the rotary shaft 20 and are configured to rotate along the inner surface of the casing 22, and a raw material supply port and a processed product discharge port are the rotary shafts. Although different in that it is arranged on both ends of 20, the operational effects performed between the press head 25 and the inner surface of the casing 22 are the same as those of the apparatus of FIG. 1. As shown in FIG. 2, a slit plate 30 that protrudes from the inner surface of the casing 22 and extends in the rotation direction of the rotary shaft 20 is provided between the press heads 25 adjacent to each other along the longitudinal direction of the rotary shaft 20. The movement time in the axial direction of the rotary shaft 20 is suppressed to ensure the residence time in the machine. At the same time, a slit-like opening 31 is provided in the slit plate 30 so that the moving speed in the axial direction can be adjusted according to the amount of the processing material.

  [Composite powder] The form of the composite powder (composite particles) according to the present invention is as follows: (1) Child particles form a coating layer on the surface of the mother particles; (2) Multiple types of child particles are processed in order To form a multilayer coating layer, (3) the child particles are confined in the mother particles, (4) the composite particles form an aggregate, (5) the child particles There are those in which the original electrical, physical, and chemical properties change depending on the coating layer, and (6) those in which one or more kinds of particles are combined to form granulated particles. These are not simply determined by the combination of materials but have various and multifunctional characteristics depending on the size and shape of the particles, the difference in the composite state, and the like.

Next, composite particles produced by carrying out the present invention will be described.
FIGS. 3 and 4 show iron powder (Fe) as a base particle coated with stabilized zirconia (PSZ) powder as a child particle, where (a) in FIG. 3 is a raw material Fe particle, (b) Is a raw material PSZ powder, and FIG. 4 is a micrograph of composite particles obtained by combining both raw materials.

  FIG. 5 is a composite particle in which copper powder (Cu) as a mother particle is coated with zirconia (ZrO2) and silicon oxide (SiO2) as child particles, and other particles completely cover the surface of the Cu particle. I can see that

  Fig. 6 (a) shows the treatment of glass ball beads (GB) with an average particle size of 30 μm as mother particles and cerium oxide (CeO2) with an average particle size of 25 nm as child particles at a rate of 70% and 30% for 30 minutes, respectively. Thus, composite particles are obtained (the particle diameter ratio of the mother particles to the child particles is 1200). FIG. 6 (b) is a cross-sectional TEM photograph of this composite particle, and it can be seen that CeO2 forms a coating on the entire surface of GB.

  FIG. 7 shows a composite of lithium cobalt oxide as a mother particle and nanocarbon as a child particle. (A) is an average particle size of 10 μm of raw material lithium cobaltate, and (b) is an average of raw material nanocarbon. The particle size is 50 nm, and (c) is a composite particle obtained by compounding these (the particle size ratio of the mother particle to the child particle is 200). This composite particle is used as an active material for a positive electrode of a lithium ion battery.

  FIG. 8 shows a composite obtained by treating titanium (Ti) with an average particle size of 50 μm as a mother particle and carbon black (CB) with an average particle size of 15 nm as a child particle at a ratio of 91% and 9% for 30 minutes, respectively. Particles (the particle size ratio of the mother particles to the child particles is 3333).

  FIG. 9 is obtained by treating copper (Cu) having an average particle size of 8 μm as a mother particle and fullerene (C60) having an average particle size of 0.7 nm as a child particle at a ratio of 95% and 5% for 2 hours, respectively. It is a cross-sectional TEM photograph of composite particles (particle size ratio of mother particles to child particles is 11429).

  FIG. 10 shows composite particles (mother particles for child particles) obtained by treating methacrylic resin (PMMA) having an average particle size of 12 μm as a parent particle and zirconium silicate (ZrO2 / SiO2) having an average particle size of 12 nm as a child particle for 2 hours. It can be seen that the PMMA surface is covered with ZrO 2 and SiO 2.

  FIG. 11 shows that MCMB (meso carbon micro beads) having an average particle size of 10 μm as a mother particle and PMMA having an average particle size of 150 nm as a child particle were treated at a ratio of 95% and 5% for 30 minutes, respectively. Composite particles (the particle size ratio of the mother particles to the child particles is 67). A coating layer made of PMMA is formed on the surface of MCMB, and this can be directly heat pressed or used as a master batch for kneading to create a conductive sheet. Further, it may be used as display particles for display.

  FIG. 12 (a) shows composite particles obtained by treating PMMA with an average particle size of 12 μm as a mother particle and TiO2 with an average particle size of 15 nm as a child particle at a rate of 67% and 33% for 3 hours, respectively ( The particle size ratio of the mother particles to the child particles is 800). (b) is obtained by heating the composite particles to 500 ° C. to melt and remove the PMMA components from the composite particles, and the broken ones are ruptured when gasified.

  FIG. 13 (a) was obtained by treating PMMA with an average particle size of 12 μm as a mother particle and tin oxide (SnO2) with an average particle size of 50 nm as a child particle at a rate of 77% and 23%, respectively, for 90 minutes. It is a composite particle (the particle size ratio of the mother particle to the child particle is 240). (b) is a cross-sectional SEM photograph of this composite particle, and it can be seen that SnO2 forms a film on the entire surface of the PMMA particle. In FIG. 14, the composite particles are heated to 500 ° C. to remove the PMMA components by melting and evaporating from the composite particles, and the broken ones burst when they are gasified.

  In addition to the above examples, combinations of particulate materials considered when forming composite particles in the future, their uses, expected effects, and the like are listed below. In any case, composite particles having various characteristics can be obtained by forming a dense composition in which different kinds of material particles are mixed by precise mixing at the particle level. In addition, there is also an effect that in the process of applying compressive force and shearing force, it is spheroidized with the mixing granulation action and the filling property is improved.

  (A) When both the mother particle and the child particle are metal, it can be alloyed in various applications, and can be applied to functionally gradient materials, heat-resistant materials, and rust-preventing materials. I can expect.

  (B) When the mother particle is a metal and the child particle is an inorganic material or the mother particle is an inorganic material and the child particle is a metal, as a sintered body, the core eddy current is reduced, the sintering density is improved, and the heat resistance and corrosion resistance. It can be used for applications such as functionally gradient materials, conductive materials, and luminescent materials.

  (C) When the mother particle is a metal and the child particle is an organic material or the mother particle is an organic material and the child particle is a metal, the conductor material is an electrode bulk, film, grease, etc., and the heat conductor material is a film, grease, etc. It can be used as a sensor by making it into a nanoballoon to provide a bulking material, a lightweight material, a heat insulating material, a sound absorbing material, etc., or to give a nanoballooned particle surface an anti-aggregation effect. Furthermore, it has heat resistance, corrosion resistance, chemical resistance, etc., and can be used for applications such as rust prevention materials, anti-mold materials, high-strength materials, flame retardant materials, light-emitting materials, and electrical insulation materials.

  (D) When the mother particle is a metal and is a liquid or liquid substance as a child particle, a thin film material of a sintered body, an acid and alkali cleaning material, an oxidizing and reducing material, hydrophilicity and hydrophobicity are imparted by forming a film on the surface of the mother particle. It can be used for materials. Further, when the liquid is a binder, a granulated product having a strong and uniform particle size can be prepared, and can be used as a filler, sintering particles, a catalyst, and the like.

  (E) When both the mother particles and the child particles are inorganic materials, the filler filling amount is increased to improve the coloring property of the pigment in the CPU sealant, and the lubricity of carbon and molybdenum sulfide coatings on bearing parts. In addition to applications such as electrical conductive materials, ultraviolet shielding materials, high-strength materials, weather resistance-imparting materials, nanoballoon fragments can also be used as cosmetics and dispersion materials. Moreover, the effect of the filling property improvement by granulation can also be expected.

  (F) When the mother particle is an inorganic material and the child particle is an organic material, or the mother particle is an organic material and the child particle is an inorganic material, it is used for high-strength materials, flame retardants, light-emitting materials, electrical conductive materials, etc. To improve the thermal conductivity and wettability of dielectric particles as a display (charged particles), secondary battery binder active materials, and fillers, use nanoballoons for bulking materials, heat insulating materials, sound absorbing materials, and on the particle surface It can also be used as a sensor with an anti-aggregation effect.

  (G) In the case where the mother particle is an inorganic particle and is a liquid or liquid substance as a child particle, a coating treatment is performed on the surface of the mother particle to improve the wettability of each substrate by coupling treatment to a dental filler. The filler can be used for applications such as hydrophilicity and hydrophobicity imparting materials. In addition, the granulated product can be expected to improve the filling property.

  (H) When both the mother particle and the child particle are organic materials, they are applied to pharmaceuticals by DDS (drug delivery system) for the purpose of sustained release, biocompatibility and control release, and UV shielding by light resistance It is possible to improve the solubility and insolubility of the resin itself by surface fusion of a material, a polymer material such as PEG and PVA, and it can be used for applications using the same kind of resin.

  (I) When the mother particle is an organic particle and is a liquid or liquid substance as a child particle, solubility and insolubility can be imparted by imparting a film to the surface of the mother particle, and hydrophilicity and hydrophobicity can be imparted.

  In addition, what can be made into a granular material with resin which is a main material as an organic material can be used for this invention, even if it is a thermosetting resin, a thermoplastic resin, and other special resin. Thermosetting resins include epoxy resin (EP), diallyl phthalate resin (PDAP), silicone resin (SI), phenol resin (PF), unsaturated polyester resin (UP), polyimide resin (PI), polyurethane resin (PUR). ), Melamine resin (MF), urea resin (UF), and the like.

  As the thermoplastic resin, ethylene vinyl acetate copolymer (EVA), ethylene vinyl alcohol strong polymerization resin (PVAL), vinyl chloride resin (PVC), chlorinated polyethylene (CPE), cellulose acetate resin (CA) polyacetal resin (POM), Polyamide resin (PA), polyacrylate resin (PAR), thermoplastic polyurethane elastomer (TPU), thermoplastic elastomer (TPE), liquid crystal polymer (LCP), polyether ether ketone (PEEK), polysulfone (PSU), polyether sal Hong (PES), high density polyethylene resin (HDPE), low density polyethylene resin (LDPE), linear low density polyethylene (LLDPE), polyethylene terephthalate (PET), polyester resin (PEN) polycarbonate resin (PC) Polystyrene resin (PS), polyphenylene ether resin (PPE), polyphenylene oxide (PPO), polyphenylene sulfide (PPS), polybutadiene resin (PBD), polybutylene terephthalate (PBT), polypropylene resin (PP), methacrylic resin (PMMA), Examples thereof include polymethylpentene resin (PMP).

  As other special resins, various thermosetting special resins and thermoplastic special resins are manufactured and sold by respective resin manufacturers, and these can also be used in the present invention if the form of the resin is granular. is there.

  The composite particles produced according to the present invention can be used as a new material material in powder metallurgy, ceramics, toner, powder coating, hybrid resin, secondary battery, and other various industrial fields.

  Further, since the composite particles of the present invention do not require addition of a solution or a binder even if they are fine composite particles, a product in which unnecessary components such as a binder are not mixed into the composite particles can be obtained, and it can be used for pharmaceuticals and foods. Available.

  Furthermore, the method for producing composite particles of the present invention can be carried out regardless of the type, combination, shape, and properties of materials by adding temperature control to the composite treatment step, and enables production of various good composite particles. The product composite particles can be used as various materials in various industrial fields, and as a new material, the range of application to new application development in the technical development field can be expanded.

Front sectional view showing an outline of a powder processing apparatus used in the practice of the present invention Front sectional drawing which shows the outline | summary of another powder processing apparatus used for implementation of this invention Micrograph of raw material powder used in one embodiment of the present invention Photomicrograph of composite particles obtained by compounding the raw material powder shown in FIG. 1 is a micrograph of a composite particle according to an embodiment of the present invention. 1 is a micrograph of a composite particle according to an embodiment of the present invention. 1 is a micrograph of a composite particle according to an embodiment of the present invention. 1 is a micrograph of a composite particle according to an embodiment of the present invention. 1 is a micrograph of a composite particle according to an embodiment of the present invention. 1 is a micrograph of a composite particle according to an embodiment of the present invention. 1 is a micrograph of a composite particle according to an embodiment of the present invention. 1 is a micrograph of a composite particle according to an embodiment of the present invention. 1 is a micrograph of a composite particle according to an embodiment of the present invention. Photomicrograph of composite particles obtained by hollowing out composite particles in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base 2 Casing 3 Cylindrical rotating body 4 To-be-processed object 5 Press head 6 Receiving surface 7 Space 8 Peripheral wall of a cylindrical rotating body 9 Hole 10 Blade member 20 Rotating shaft 22 Casing 25 Press head 30 Slit plate 31 Opening

Claims (5)

  Applying compressive force and shear force in a mixed state to core particles that are cores and finer child particles, and fixing the child particles on the surface of the mother particles or forming a coating layer of the child particles to form a composite A method for producing composite particles characterized by the above.   2. The method for producing composite particles according to claim 1, wherein the mother particles have a particle size of 10 nm or more, the child particles have a particle size of 1 μm or less, and the particle size ratio of the mother particles to the child particles is 10 or more.   The core mother particles and finer child particles are mixed to give a compressive force and a shearing force in a mixed state to fix the child particles on the surface of the mother particles or to form a coating layer of the child particles. Composite particles.   The core particle as a core is made of a melting or soluble material, and the child particle is fixed to the surface of the mother particle by applying a compressive force and a shearing force in a mixed state of the mother particle and a child particle finer than the mother particle. A method for producing composite particles, comprising forming composite particles by forming a coating layer of particles, and then melting or dissolving only the mother particle components from the composite particles to form a hollow shape. The core particle as a core is made of a melting or soluble material, and the child particle is fixed to the surface of the mother particle by applying a compressive force and a shearing force in a mixed state of the mother particle and a child particle finer than the mother particle. A composite particle in which a composite particle is manufactured by forming a particle coating layer, and then only a mother particle component is melted or dissolved and removed from the composite particle to form a hollow shape.