KR100567234B1 - Glass particle, glass particle aggregate, and the manufacturing method of the glass particle - Google Patents

Abstract

The mixing process in the use which mixes a glass powder, a metal powder, etc. is removed, and the glass particle which previously contained the metal particle in the glass particle is obtained.

The manufacturing method of the glass particle of this invention mixes the process of coating the surface of the metal particle to contain with an oxide film, and the said metal particle coat | covered the surface with the oxide film in the raw material solution containing the structural element of the said glass, and And a step of producing a slurry and a step of thermally decomposing the raw material slurry into droplets by introducing it into a high temperature furnace.

Glass particle, glass particle assembly, glass particle manufacturing method, metal particle, oxide film

Description

Glass Particles, Glass Particle Aggregates, and Methods for Manufacturing Glass Particles {GLASS PARTICLE, GLASS PARTICLE AGGREGATE, AND THE MANUFACTURING METHOD OF THE GLASS PARTICLE}

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram which shows the manufacturing process of an example of the manufacturing method of the metal containing glass particle of this invention.

2 shows nickel particles subjected to a silicon oxide coat treatment.

3 is a spray heat analysis apparatus used in the present invention.

4 is an XRD chart of a metal-containing glass particle aggregate of the present invention produced under the conditions of Example 1. FIG.

5 is an XRD chart of a conventional glass particle aggregate.

6 is an XRD chart of the metal-containing glass particle aggregate of the present invention produced under the conditions of Examples 2 to 4. FIG.

7 is a TG-DTA chart of the metal-containing glass particle aggregate of the present invention produced under the conditions of Example 1. FIG.

8 is a TG-DTA chart of a conventional glass particle aggregate.

9 is a secondary electron image and a reflective electron image of SEM photographs showing metal-containing glass particles of the present invention produced under the conditions of Example 1. FIG.

10 is a secondary electron image and a reflected electron image of SEM photographs showing conventional glass particles.

11 is a secondary electron image and a reflected electron image of SEM photographs showing metal-containing glass particles of the present invention produced under the conditions of Example 2. FIG.

12 is a TEM photograph and EDX observation point showing the metal-containing glass particles of the present invention produced under the conditions of Example 2. FIG.

FIG. 13 is an EDX chart of the entire TEM photograph shown in FIG. 12.

FIG. 14 is an EDX chart of EDX measurement point 1 in FIG. 12.

FIG. 15 is an EDX chart of EDX measurement point 2 in FIG. 12.

<Explanation of simple sign>

1: manufacturing process of metal particles

2: process to coat oxide film

3: process of making spray solution

4: mixed dispersion treatment process of solution

6: spray pyrolysis process

The present invention relates to a glass particle, a glass particle aggregate, and a method for producing the glass particle, and more particularly, to a glass particle, a glass particle aggregate, and a method for producing a glass particle in which metal particles are contained.

Background Art Glass materials have conventionally been used in various fields such as ceramic low temperature sintering aids, substrate materials, electrode bonding materials, and insulating coating overcoat materials for forming ceramic electronic components. For example, in a multilayer ceramic capacitor, what added the glass particle as a sintering aid is used, or it is mixed and used as a glass frit in an external electrode. Moreover, in a resistive material, it is used for formation of an insulation resistance part.

As such, the glass material is used in many fields, such as mixing with a ceramic or metal, or using the insulating property alone, but the conventional glass material is obtained by mechanically pulverizing a bulk glass produced by a melt quenching method. There are many. For this reason, there is a limit to the particle size that can be micronized, and the particle size distribution is wide, the shape is not uniform, and there are characteristics such as a large amount of aggregates formed.

When using this glass material for the said use, it mixes mechanically with materials, such as a ceramic, a metal material, and an organic substance, and is used. In the use which mixes such a molten quenching glass material with another substance, it is difficult to obtain a uniformly dispersed state with high density because of the unevenness of the shape and the large amount of aggregates.

With respect to these problems, glass fine particles (for example, refer to Patent Document 1) in which oxide particles are enclosed inside glass particles, or metal powders in which a glass thin film is formed on at least a part of metal powder are proposed (for example, , Patent Document 2).

[Patent Document 1] Japanese Unexamined Patent Publication No. 2001-302282

[Patent Document 2] Japanese Unexamined Patent Publication No. 10-330802

However, in patent document 1, the process of preparing glass powder as a raw material powder is needed, and the number of processes increases. In addition, since the oxide-encapsulated glass is formed through a gaseous phase by plasma, it is not possible to use a metal type such as solid solution in the glass, cannot contain metal particles, or limit the glass composition. have.

In addition, Patent Document 2 discloses a method for producing a metal powder coated on a glass layer by spray pyrolysis. Specifically, a metal powder is deposited by spraying a solution containing one or two or more thermally decomposable metal compounds into fine droplets, and heating the droplets to a temperature higher than the decomposition temperature of the metal compound to thermally decompose the metal powder. )do. At this time, an oxide precursor or the like is added to the metal compound solution so that the glass coating can be performed simultaneously with the generation of the metal powder.

However, a mixed solution or mixed sol such as an inorganic compound (acetate, chloride, etc.), an organic compound (metal alkoxide, etc.), a sol (such as a silicon oxide sol or an aluminum oxide sol) is used as the raw material solution used for the spray pyrolysis method. In general, in consideration of raw material prices and production efficiency, at least a part of the glass constituent elements is used by dissolving soluble salts such as acetate, sulfate, acetate and chloride in a solvent. For this reason, it is necessary to adjust pH of a solution to acidity from solution stability, and strong acids, such as acetic acid and sulfuric acid, were used. When the metal particle contained in this raw material solution is added, a metal will melt | dissolve in a solution and it will become a factor different from the objective of the composition of a metal and glass composition.                         

Moreover, when spray thermal decomposition of this raw material solution is carried out in air | atmosphere, there exists a subject that a metal particle may be exposed to a high temperature atmosphere, and will oxidize.

This invention is made | formed in view of the point mentioned above, Comprising: It aims at eliminating the mixing process of a glass powder and a metal powder in the use like mixing and using a glass powder and a metal powder.

Moreover, there is no limitation in the kind of metal and the composition of glass which are contained in glass particle, and an object is to provide the glass particle, the glass particle aggregate, and the manufacturing method of a glass particle which contained the metal of a wide composition range.

Furthermore, even when a strong acid such as acetic acid or sulfuric acid is used as the raw material solution of the spray pyrolysis method, the metal particles do not dissolve, and the glass particles and glass particle aggregates that can be prevented from being oxidized even if they are brought into contact with the air during spray thermal decomposition. And it aims at providing the manufacturing method of a glass particle.

In this invention, in order to achieve the objective mentioned above, it comprises as follows.

That is, the glass particle of this invention is a glass particle in which the metal particle was contained, It is characterized by the surface of the said metal particle being coat | covered with the oxide film.

It is preferable that the said oxide film contains the structural element of the said glass particle.

The oxide film preferably contains at least any one of silicon oxide, boron oxide, and phosphorus oxide.

It is preferable that the particle diameter of the said glass particle is 2 times or more and 200,000 times or less of the particle diameter of the said metal particle contained.

Moreover, the glass particle of this invention is characterized by containing the said some metal particle in the state disperse | distributed.

Moreover, the glass particle of this invention has a multi-layered structure in which the some glass layer which consists of different glass components is laminated | stacked outward from the center of the said glass particle, It is characterized by the above-mentioned.

Moreover, the glass particle aggregate of this invention is a glass particle aggregate by which the said glass particle aggregates, It is characterized by the average particle diameter being 0.01 micrometer or more and 10 micrometers or less.

Moreover, the manufacturing method of the glass particle of this invention is a manufacturing method of the glass particle in which the metal particle was contained, The process of covering the surface of the said metal particle to contain with an oxide film, and the surface in the solution containing the structural element of glass. And a step of mixing the metal particles covered with the oxide film to produce a raw material slurry, and a step of dropping the raw material slurry into a high temperature furnace to thermally decompose the raw material slurry.

It is preferable that the temperature of the thermal decomposition is higher than the glass glass transition temperature.

Moreover, the manufacturing method of the glass particle of this invention mixes the obtained glass particle in the solution containing the said glass particle and another glass component, and prepares a raw material slurry, The liquid raw material slurry is made into droplets, and a high temperature furnace body is made. It is characterized by further including the step of introducing into the inside and thermally decomposes.

Embodiment of the Invention

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail.

The glass particle of this invention is a glass particle (henceforth "metal containing glass particle") in which metal particle is contained. Moreover, the glass particle aggregate of this invention consists of a plurality of said metal-containing glass particle aggregates, and represents a glass powder specifically ,.

The glass constituent elements of the glass particles may include at least one of Si, B, P, Li, Na, K, Mg, Ca, Ti, Cu, Al, Ba, Zn, Ga, Ge, Pb, and Bi. Can be. Specifically, it is preferable to contain at least one of silicon oxide, boron oxide and phosphorus oxide which are network oxides. The glass particles are said to have a glass transition temperature and a glass softening temperature, and may be comprised only with amorphous glass, and may contain crystalline glass. Moreover, you may contain the crystallized glass which crystallizes when the glass particle is heated.

The particle diameter of the glass particles is not particularly limited as long as it contains metal particles. However, the particle diameter of the glass particles is preferably 0.1 µm to 1000 µm. The particle diameter of glass particle | grains is too small, for example, when producing glass particle by the spray pyrolysis method mentioned later, production efficiency may fall, for example, it is necessary to slow down the supply rate of a raw material slurry. On the other hand, when the particle diameter of glass particle is too large, formation of glass particle may take time, and a large apparatus may be needed.

Moreover, it is preferable that the particle diameter of a glass particle is 2 times or more and 200,000 times or less of the particle diameter of a metal particle. When the particle diameter of glass particle is 2 times or more of the particle diameter of metal particle, it becomes easy to contain metal particle. Moreover, since the quantity of the glass particle with respect to a metal particle becomes comparatively large, the function of the glass particle as a binder and a bonding agent is strengthened. Therefore, when metal containing glass particles with such a large amount of glass are relatively used, it is unnecessary to add a binder or a bonding agent such as a glass frit. In addition, an upper limit of 200,000 times or less is derived from the practical range of the particle diameter of the glass particle mentioned above, and the practical range of the particle diameter of the metal particle mentioned later.

Moreover, although it is preferable that the shape of a glass particle is circular, it may be close to circular, and what is necessary is just a shape which is not inappropriate for the intended use.

In addition, the glass particle may have a multilayered structure in which a plurality of glass layers made of different glass components are laminated outward from the center of the glass particles. "Other glass component" here does not only mean that the elements which comprise glass differ. The term "other glass components" means that the elements constituting the glass are the same, and the properties as glass, such as glass transition temperature, glass softening temperature, crystallization temperature, or melting temperature, are different. Therefore, when the glass particles having this multi-layered structure are rounded, a plurality of layers having different properties from the center to the outside, such as the so-called baumkuchen, are formed, such as the rings of a tree.

By setting it as such a multilayered structure, since the characteristic can be inclined, for example to the outer side and center part of glass particle, it becomes possible to give the characteristic that the outer glass component softens at low temperature and the glass component of a center part does not become high temperature.

By using the metal-containing glass particles having such a multilayer high layer, for example, a glass component having different thermal properties can be present as one particle, and by selecting a suitable one for the glass component, the glass transition temperature, crystallization temperature, melting Various characteristics, such as temperature, can be designed arbitrarily.

The number of layers of a glass layer is suitably selected according to the objective. In addition, the glass composition of each glass layer is not specifically limited because what suits the characteristic according to the use used, such as a sintering aid and paste, is selected suitably.

As metal particle, 1 or more types of metals, such as Cu, Ni, Ag, Pt, Au, Pd, Al, should just be contained. It is also possible to use an alloy containing a single metal component or a multimetal component, a mixture of single metal components, a mixture of a single metal and an alloy, or a mixture of alloys. In many ceramic electronic components such as multilayer ceramic capacitors, nickel or copper, which is a nonmetal, is often used as the electrode material. Therefore, the metal particles are preferably nickel, copper, a nickel alloy, or a copper alloy.

The metal particles are preferably contained completely inside the glass particles, but a part thereof may be exposed from the surface of the glass particles. In the present specification, the meaning of "inclusion" also includes a case where a part of the metal particles is exposed from the surface of the glass particles.

 Metal particles have an oxide film on the surface. As a result, even when the glass particles are mixed with a strong acid solvent, for example, the metal particles may be stably present without melting. The oxide film may contain nitride or carbide. Moreover, it is preferable that an oxide film is comprised from the substance which is compatible with the glass component of glass particle, and it is more preferable to contain the structural element of glass particle. By forming such an oxide film, metal-containing glass particles rich in variation can be obtained regardless of the type of metal or the glass composition.

It is preferable that the particle diameter of a metal particle is 5 nm-100 micrometers practically. If the particle diameter of the metal particles becomes too small, it becomes technically difficult to manufacture the metal particles. On the other hand, when the particle diameter of a metal particle becomes large too much, the weight of a metal containing glass particle becomes heavy, and when it mixes with a solvent, it is easy to settle and dispersibility may fall.

Moreover, the some metal particle may be contained in the glass particle in the state disperse | distributed. This structure is effective, for example, when dispersing many metal particles in a solvent.

In addition, the metal-containing glass particles can be used as an aggregate. Specifically, each particle represents the glass powder etc. which consist of the metal-containing glass particle of this invention.

Although these metallic inclusion glass particles have the same characteristics even when used alone, they can be mixed with metallic inclusion glass particles having different characteristics and used as an aggregate of glass particles.

This metallic inclusion glass particle aggregate can be used in various forms. For example, it can use for a thin film, a bulk molded object, a sheet | seat, a paste, etc.

Moreover, it is preferable that the average particle diameter of a metallic inclusion glass particle assembly exists in the range of 0.01 micrometer or more and 10 micrometers or less. In order to obtain a metal-containing glass particle aggregate having an average particle diameter of less than 0.01 μm, the concentration of the solution is reduced, and thus a particle atomization method capable of forming minute droplets such as electrostatic spraying or ultrasonic spraying is required. The production efficiency of can deteriorate and adversely affect productivity. On the other hand, when the average particle diameter exceeds 10 µm, adverse effects may occur on printability and surface smoothness when used as a mixture with ceramics or as a paste.

Therefore, in the use which does not affect productivity, printability, or surface smoothness of metal-containing glass particles, it may be outside this average particle diameter range. An average particle diameter here is an average value of the particle diameter calculated | required from the particulate form obtained by the observation means which can observe a particle shape, such as a scanning electron microscope.

EMBODIMENT OF THE INVENTION The metal-containing glass particle of this invention is demonstrated in more detail, describing the manufacturing method of the metal-containing glass particle which is one Embodiment of this invention below.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram which shows the process of the manufacturing method of the metal containing glass particle which concerns on one Embodiment of this invention.

The manufacturing method of the metal-containing glass particle of this embodiment includes the process (1) of manufacturing the metal particle contained in a glass particle, the process (2) of coat | covering the surface of a metal with an oxide film, and the structural element of glass. Step (3) of producing a spray solution, mixing (dispersing) metal particles coated with an oxide film on the spray solution to produce a raw material slurry, and heating the raw material slurry in the form of fine droplets. It is provided with the spray-heat decomposition process 6 which introduce | transduces into a furnace body, and thermally decomposes a raw material slurry by the radiant heat from a furnace body, and obtains metal-containing glass particle 5 by quenching.

Spray pyrolysis is also suitable for obtaining circular glass particles. A solution containing glass constituent elements is introduced into the heated furnace as fine droplets to thermally decompose the raw material solution by radiant heat from the furnace and It is a method by which the target glass particle can be obtained by doing this.

However, as a raw material solution of spray pyrolysis, generally, at least part of free constituent elements is dissolved in a solvent by dissolving soluble salts such as acetate, sulfate, acetate, chloride, and the like. It is necessary to adjust it, and strong acids, such as acetic acid and sulfuric acid, are used.

Therefore, when the particle | grains of the metal which are to be contained in the glass particle are added and mixed to this raw material solution, there exists a problem that a metal melts and the composition of the surface of a metal and the contact part of glass changes. In addition, when spray thermal decomposition of the raw material solution in the air, there is a problem that the metal particles are exposed to a high temperature atmosphere to oxidize.

Also in this sense, it is preferable to provide the process of modifying the surface of the particle | grains of the metal contained in glass particle like this embodiment. In other words, it is preferable that the surface of the metal is modified with an oxide film having a solvent resistance to acid and / or oxidation resistance.

The production apparatus used for the embodiment of the present invention, that is, the spray pyrolysis apparatus, may be a known one, and the heating temperature, particle conveyance rate, spraying method and spraying conditions of the furnace body may include the type of spray raw material solution and the composition of glass. It is appropriately selected depending on the characteristics and characteristics. By using the spray pyrolysis method in this way, as in the prior art, using the glass powder alone and the metal powder alone as raw materials, the raw material slurry in which the metal particles are dispersed in the glass solution is not directly subjected to the process of grinding or mixing the raw materials. Since the metal-containing glass particles can be formed, the metal-containing glass particles can be obtained in a short time at low cost.

Moreover, in order to mix the structural element of metal containing glass particle in a slurry state, it has the characteristic that the composition of glass particle becomes uniform. In such a spray pyrolysis method, as long as the slurry can be thermally decomposed to supply the amount of heat generated by the particles, a well-known heating method such as a direct heating method by a flame can be used, as well as heating by radiant heat from the furnace body.

It is necessary to make heating temperature of the raw material slurry in this spray pyrolysis method higher than the glass transition temperature made into the objective at least, Preferably glass particle can be achieved easily by setting to more than melting temperature of glass.

Moreover, in glass manufacture, quenching of molten glass is generally performed, and also the supply of the gas for quenching of glass particles etc. is performed also in glass particle synthesis by the use of the high temperature gaseous field using a thermal plasma. In the method according to the invention, since the temperature gradient of the conveyance path from the furnace body to which the thermal decomposition is performed is a steep slope, it is not particularly necessary to supply the quenching gas, and the conveying speed of the glass particles is controlled. This can be easily synthesized. Of course, some glass compositions require a steeper gradient than a set temperature gradient, and since cooling means such as supply of cooling gas are required, this cooling means can also be used.

Although the method of atomizing the raw material slurry can be a known method such as a two-fluid nozzle spraying method, an ultrasonic spraying method, or an electrostatic spraying method, a method of atomizing may be considered in view of uniformly atomizing the productivity, the spray solution, and the suspended metal particles. It is preferable to use a two-fluid nozzle spray method.

The target diameter can be obtained by adjusting the density | concentration of a raw material slurry, and atomization conditions for the particle diameter of the metal-containing glass particle to produce. That is, in the case of using the two-fluid nozzle spraying method, in order to reduce the particle diameter of the metal-containing glass particles, the concentration of the raw material slurry may be reduced, the supply rate of the raw material slurry supplied to the nozzle may be slowed, and the flow rate of the spraying gas may be increased. On the contrary, in order to increase the particle size of the metal-containing glass particles, the concentration of the raw material slurry may be increased, the feed rate of the raw material slurry supplied to the nozzle may be increased, and the flow rate of the spraying gas may be reduced.

Either way, the size of the droplet-shaped raw material slurry may be such that the metal particles are contained within the glass particles, and for this purpose, the size of the droplet-shaped raw material slurry is added to the raw material slurry. It is good to make it into 2 times or more of particle diameter, for example, and it will be in the state which the metal particle contained inside the glass particle.

Thus, since the particle diameter of the metal-containing glass particles produced by the spray pyrolysis method can be adjusted in the step of making the raw material slurry invincible, in order to control the particle diameter of the metal-containing glass particles, it is pulverized or classified after synthesis. There is no need to perform post-processing. Therefore, metal-containing glass particles can be obtained with high efficiency by a small process. Of course, this does not restrict the processing such as grinding or classification depending on the purpose.

In addition, the metal-containing glass particles synthesized by the spray pyrolysis method are recovered by a recovery apparatus such as a filter. There is no restriction | limiting in particular also about this collection method.

Furthermore, this invention is characterized by using it as a raw material slurry which mixed the particle | grains of the metal contained in the solution containing the structural element of glass particle, and introduce | transduced into this high temperature furnace the thing which made this raw material slurry into the droplet state. It is characterized by producing by thermal decomposition.

Therefore, since the metal particles contained already exist in the state of being dispersed in the spray-shaped droplet by the said method, if the metal particles contained in the raw material slurry are adjusted to a desired particle diameter and concentration, an anisotropy etc. It is possible to obtain metal-containing glass particles without the need of depositing a metal by performing a heat treatment of. In addition, even in a reaction such as volume shrinkage due to thermal decomposition of the raw material slurry, the particle size and concentration of the metal particles to be contained do not change, so that the inside of the glass particles can be contained so as to have a desired particle size and concentration.

Here, the density | concentration of the metal particle contained means a volume concentration.

In the present invention, as described above, particles of the metal for inclusion suspended in the raw material slurry are subjected to surface modification for coating the surface with an oxide film containing a constituent element of glass. By performing this surface-soluble surface modification, even if the particle | grains of the metal contained in a raw material slurry are suspended, it can exist stably, without melt | dissolving in the solvent of a strong acid.

Moreover, in this way, in the manufacturing method of the metal-containing glass particle by this invention, it is preferable to provide solvent resistance by the process of forming an oxide film in the surface of the metal to be contained, and by this the kind and shape of the metal contained essentially. The characteristics of the metal, such as the particle size, are not limited, and the metal of the constituent elements of the glass may also be contained.

As the oxide film containing the glass constituent elements of the glass particles, silicon oxide, which is a network structure constituent element of the glass, can be suitably used, and there is no particular limitation as long as it has solvent resistance to an acidic solution, and includes nitride, carbide, etc. You may also The formation method of the oxide containing this structural element of glass can be easily obtained by hydrolysis of a metal alkoxide. An example of the formation method of a specific surface modification oxide is described below.

First, the contained metal particles are precisely weighed in a desired amount to be dispersed in a non-aqueous solvent such as ethanol. In a non-aqueous solvent in which the metal particles are dispersed, a basis weight is precisely added in an amount which becomes a coat thickness for the purpose of metal alkoxide such as ethyl orthosilicate, which is a raw material of the surface-modifying material, and the dispersion treatment is performed. Do it.

Next, what added water of the quantity enough to fully hydrolyze ethyl orthosilicate in non-aqueous solvents, such as ethanol, is prepared. Next, while the dispersion treatment is performed in a solution in which the metal and the metal alkoxide are dispersed, a solution for hydrolysis added with water is added dropwise, the metal alkoxide is hydrolyzed to give an oxide surface modification on the surface of the metal particles. Form.

Such a method is an example of the method of forming the surface-modified oxide, and of course, there is no problem even if the surface-modified oxide-forming method on the surface of other metal particles is used. As the method for forming the surface-modified oxide, a CVD method, a sputtering method, or another liquid phase, which is a coating method in the gas phase, may be used.

By modifying the surface of the metal particles contained in this manner to form an oxide film, the oxidation reaction of the inclusion metals seen during thermal decomposition of the raw material slurry can be suppressed, so that the atmosphere during spray thermal decomposition can be referred to as an atmospheric atmosphere. It also has the feature of not requiring special adjustment such as using a reducing atmosphere to suppress oxidation. Therefore, it is preferable to perform this surface modification, even when the mixture of the organometallic compound which does not use an acidic solution, or a sol mixture is used for a raw material slurry.

In addition, the metal-containing glass particles obtained by using an acidic solution, an organometallic compound, and the like as the raw material slurry of the present invention remain constituent elements such as an acidic solution and an organometallic compound, such as nitrogen or carbon, in a few tens of ppm to 1.0 wt% or less. There is a possibility that the residual amount is appropriately adjusted by the use of the glass particles of the present invention.

The metal-containing glass particles produced as described above were suspended in a raw material slurry containing a glass component having different properties, fine droplets were formed by a desired spraying method, and the glass component of the raw material slurry was suspended by thermal decomposition. By forming on the surface of the metal-containing glass particles, glass particles having a structure in which the metal-containing glass particles are used as a nucleus and the surface is coated with other glass components can be obtained.

Moreover, by repeating the manufacturing process of the metal containing glass particle which has this structure, it becomes possible to give a multilayered structure of at least 2 layers or more, and can control various characteristics more precisely. For example, the metal-containing glass particles can be produced by performing a spray pyrolysis method in the same manner as when producing the metal-containing glass particles using a raw material slurry containing a glass component having a melting point lower than the melting point of the glass composition.

EXAMPLE

Hereinafter, the detail of this invention is demonstrated based on an Example.

<Example 1>

Fabrication of Inclusion Metals

Nickel particles as metal particles contained therein were produced by the gas evaporation method. In a reactor adjusted to an atmospheric pressure of 6.65 kPa in a helium atmosphere, 80 g of nickel ingot was placed in a magnesium oxide melting furnace, and heated to about 1800 degrees by eduction heating by an induction coil to which an induction current 54A was applied to evaporate. The evaporated nickel vapor was cooled in a helium gas stream supplied at a rate of 4 liters per minute and recovered by a filter. The specific surface area size of the produced nickel particle aggregate was 30 nm.

In the oxide coat ethanol for imparting the solvent resistance to the inclusion metal, the nickel particle aggregate prepared by the above method is placed, and the amount of ethyl ortho which is capable of forming a silicon oxide film having a thickness of 2 nm, 6 nm or 8 nm on the surface of the nickel particle aggregate. A silicate (TEOS) was added and 30 minutes dispersion processing was performed by an ultrasonic disperser. Subsequently, 5 times the amount of ammonia and 10 times the amount of water of TEOS was added to the ethanol, followed by sufficient stirring. Then, ammonia and water were added to the ethanol solution containing the nickel particle aggregate and TEOS at a rate of 1 cc per second. The mixed ethanol solution was added dropwise to perform a hydrolysis reaction of TEOS. After this hydrolysis, the nickel particle aggregate in which the silicon oxide film was formed by filtration was separated from the solvent, and ethanol was added to ultrasonic cleaning to remove unreacted TEOS and ammonia. Thereafter, vacuum drying was performed to obtain a nickel particle assembly in which silicon oxide films of 2 nm, 6 nm, and 8 nm were formed, respectively.

The result of having observed the nickel particle aggregate produced by this hydrolysis process with the transmission electron microscope (TEM) is shown in FIG.

The film thickness of the silicon oxide film on the surface is 2 nm, 6 nm, or 8 nm as designed, and in the nickel particle aggregate in which the 2 nm silicon oxide film is formed as shown in Fig. 2 (a), the unevenness of the surface of the silicon oxide film is large and is not formed to a uniform thickness. However, in the nickel particle aggregate in which the silicon oxide films of 6 nm and 8 nm, respectively, shown in Figs. 2 (b) and (c) were formed, there was no irregularities on the surface thereof and had a uniform thickness on the entire particle surface.

Next, the nickel particle aggregate in which this silicon oxide film was formed was put into the acetic acid spray raw material solution adjusted to pH2, and the melt | dissolution state was confirmed by the nickel ion tester, As a result, the nickel particle aggregate whose thickness of a silicon oxide film is 2 nm is 30 minutes after addition. Nickel ions were detected later. However, it was found that nickel ions were not detected even after 16 hours from the addition of the nickel oxide aggregates having a thickness of 6 nm and 8 nm in the thickness of the silicon oxide film, and the provision of solvent resistance in the acidic solution was sufficiently functioned. As a result, the thickness of the silicon oxide film formed on the nickel particle aggregate is preferably 5 nm or more, and it is indispensable that the solvent-resistant substance applied to the surface of the nickel particles is indispensable for the silicon oxide film to be formed on the entire surface of the particle during long-time synthesis. .

In addition, as a comparative example, the nickel particle aggregate which does not form an oxide film on the surface was put into the acetic acid spray raw material solution adjusted to pH2, and when melt | dissolution was confirmed by the nickel ion tester, foaming generate | occur | produces after 5 minutes of addition, and it is 25 ppm It was found that the nickel ions were dissolved. In addition, it was confirmed that the nickel particle aggregate was melt | dissolving completely in the state which passed 16 hours after input.

Fabrication of Raw Material Slurry

In an acidic solution, silicon oxide sol (particle size <5 nm), boric acid, barium carbonate, and lithium carbonate are precisely weighed so as to be 28: 21: 43: 8 in terms of oxide, and placed in a beaker. Water to 4 wt% was added at the oxide concentration, and each constituent element was dissolved to obtain a spray raw material solution (A).

Then, the nickel particle aggregate in which the silicon oxide film was formed to a thickness of 8 nm was basis weighted so as to have a concentration of 1.2 vol% in terms of metal nickel, and ultrasonic dispersion in water for 30 minutes was added to the spray raw material solution (A) to give a total concentration. The raw material slurry (B) in which the nickel particle aggregate was disperse | distributed was adjusted by fully adjusting so that it might become 2.5 wt% in conversion of the oxide. Although this raw material slurry (B) was stirred for 2 hours and the nickel ion concentration in the solution was measured, nickel ion was not detected.

In this case, a concentration of 1.2 vol% of metallic nickel is a concentration at which about 100 nickel particles having a particle size of 30 nm are dispersed when a glass particle having a particle size of 1 μm is assumed. Furthermore, 2.5 wt% of the concentration of the raw material slurry (B) is a concentration capable of obtaining 1 μm of glass particles when the particle diameter of the droplet having the raw material slurry (B) in the form of a spray is 5 μm.

Fabrication of metal-containing glass particles by spray pyrolysis

The spray pyrolysis apparatus used for the manufacturing method of the metal containing glass particle of this invention is shown in FIG. This spray pyrolysis apparatus is a known apparatus as described above.

In the vertical spray pyrolysis furnace of the radiant heat heating method in which the temperature of the furnace body was adjusted to 900 degrees by an electric heater, the above-described raw material slurry (B) was charged at a rate of 10 mL / min by a raw material pump at a rate of 2 kgf / cm ^2. By supplying air at a pressure of 20 L / min to the two-fluid nozzle, respectively, the produced invincible was introduced into the furnace to cause a thermal decomposition reaction. On the other hand, in a furnace tube having an inner diameter of 200 mm, a length of 1000 mm, and a heating length of 1000 mm, the thermal decomposition reaction was caused to have a carrier gas flow rate of 35 L / min and an atomization amount of 100 mL / h, with a residence time of 8.6 s. The spray atmosphere at this time is air. In addition, heat processing like Annihil was not performed here. The metal-containing glass particle aggregate produced by this pyrolysis reaction was introduced into the recovery portion of the product collector provided with the bug filter by airflow and recovered.

<Examples 2 to 4>

Nickel ingots were evaporated in a reactor in which the production atmosphere pressure was adjusted to 1.13 kPa using the method and procedure for fabricating the inclusion metal shown in Example 1 to obtain a nickel particle assembly having a specific surface area size of 15 nm. The nickel particle aggregate in which the silicon oxide film of 8 nm was formed in the nickel particle surface was obtained using the oxide coat method shown in Example 1 for this nickel particle aggregate. The nickel particle aggregate in which the silicon oxide film was formed was basis weighted so as to have a concentration of 1.2, 2.4, and 3.6 vol% in terms of metal nickel in the spray raw material solution (A) shown in Example 1, and sprayed with ultrasonic dispersion for 30 minutes in water. It added to the raw material solution (A), it adjusted so that the total concentration might be 2.5 wt% in conversion of an oxide, and fully stirred, and obtained the raw material slurry which disperse | distributes a metal nickel particle aggregate.

Spraying thermal decomposition was performed on the raw material slurry containing this metal nickel particle on the conditions similar to Example 1, and the metal-containing glass particle of Examples 2-4 was obtained.

Comparative Example 1

The glass particle aggregate using the spray raw material solution (A) which does not contain nickel was produced by the above conditions and procedure for the purpose of comparing the characteristic with the metal containing glass particle.

As a result of identifying the crystal phases of the metal-containing glass particle aggregate produced in Example 1 and the glass particle aggregate of Comparative Example 1 using X-ray lime (XRD), the metal-containing glass particle aggregate is shown in FIG. 4. Likewise, peaks attributable to metal nickel and broad peaks around 20 ° to 40 ° observed in the glass particle aggregates not containing nickel shown in FIG. 5 are observed, and the contained nickel is present in the metal state. The point and the glass component turned into glass particles.

Furthermore, from the XRD chart of the metal-containing glass particle aggregates produced in Examples 2 to 4 in which the metal nickel concentrations shown in FIG. The amount of metal in the metal-containing glass particle aggregate is shown to be controlled by the amount of metal particles to be mixed in the raw material slurry. 6 shows Comparative Example 1 together.

Table 1 shows each characteristic list of Examples 1-4 and Comparative Example 1. FIG.

Nickel particle size (nm) Nickel Concentration (vol%) Nickel peak Nickel peak strength (cps) Glass transition temperature (℃) Crystallization temperature (℃) Melting temperature (℃) Particle size (μm) Comparative Example 1 - 0 none 0 455 621 883 0.44 Example 1 30 1.2 has exist 424 456 617 883 0.48 Example 2 15 1.2 has exist 50 460 623 863 0.52 Example 3 15 2.4 has exist 130 461 617 867 0.43 Example 4 15 3.6 has exist 205 463 615 874 0.42

In addition, the glass properties of the glass particle aggregates produced in Example 1 and Comparative Example 1 were evaluated by differential thermal analysis (TG-DTA). As a result, as shown in Fig. 7 and Fig. 8, both samples showed peaks at the same temperature due to glass transition, vitrification, and melting, and exhibited properties equivalent to those of glass particle aggregates containing no nickel even when they contained nickel. It was.

Furthermore, as shown in Table 1 above, it was found that the glass properties of the metal-containing glass particle aggregates produced by varying the metal nickel concentration in the raw material slurry also had the same characteristics as the glass particle aggregates of Comparative Example 1, and the metals in the raw material slurry were It was shown that even if the nickel concentration was increased, there was no significant effect on the glass particle aggregate. This showed that the property control of the glass particle which is one of the effects of the glass particle created by the method of this invention can be performed by the glass composition of a raw material slurry.

The glass particles of Example 1, Comparative Example 1, and Example 2 were observed with a scanning electron microscope. The results are shown in Figs. 9, 10, and 11, respectively. In each figure, (a) shows the secondary electron image, and (b) shows the SEM photograph, respectively.

As a result of evaluating the particle shape and average particle diameter by this scanning electron microscope, as shown in FIG. 9, the glass particle containing nickel had the same circular shape as the glass particle which does not contain shown in FIG. In addition, the average particle diameter was 0.48 micrometers of metallic inclusion glass particles, and 0.44 micrometers of glass particles which are not contained were equivalent. In addition, the average particle diameter of nickel which is an embedded metal was 15 nm.

Furthermore, as shown in Table 1, it was found that the particle size of the metal-containing glass particles produced by changing the metal nickel concentration in the raw material slurry was the same size as that of the glass particles of Comparative Example 1, and the glass particles were increased even if the metal nickel concentration in the raw material slurry was increased. It was shown that there is no significant effect on the particle diameter of, and that the particle diameter of the glass particles, which is one of the effects of the glass particles produced by the method of the present invention, can be controlled by the glass component concentration of the raw material slurry.

In addition, in the observation with a scanning electron microscope, compared with FIG. 9 and FIG. 10, the thing which does not contain nickel as shown in FIG. 10 did not show a clear contrast difference in a secondary electron image and a reflection electron image, compared with FIG. As shown in Fig. 9, in the glass particles containing nickel produced in Example 1, a clear contrast indicating the presence of a metal was observed in the reflection electron phase, and the presence of nickel in the metal state was suggested in the glass particles.

Furthermore, as shown in FIG. 11, in the secondary electron image of the sample produced in the state of Example 2 obtained by mixing nickel particle with a particle diameter smaller than Example 1 in the raw material solution A at the same density | concentration, compared with FIG. It is shown that nickel particles containing a small amount of clear contrast and small particle diameter are contained, and the particle diameter of nickel contained in the glass particles, which is one of the effects of the glass particles produced by the method of the present invention, is mixed in the raw material slurry. It was found that can be controlled by the particle size of nickel.

The compositional evaluation of the particle | grains of the metal-containing glass particle aggregate was performed using the transmission electron microscope (TEM) and the energy dispersive X-ray analysis microscope (EDX). The measurement point of the TEM image and EDX of the sample produced on condition of Example 3 is shown in FIG. 13, the EDX chart of the whole observation field is shown.

As shown in FIG. 13, the observed metallic inclusion glass particle aggregates detect peaks attributable to silicon and barium, which are the major constituent elements of glass, and peaks of nickel, the inclusion metal, and include metallic components in the glass particles. Indicated. In addition, the peak of copper in FIG. 13 is that of a TEM observation grid.

The result of having analyzed the detailed composition inside the particle | grains of this metal containing glass particle in each part of the measuring point 1 and the measuring point 2 is shown to FIG. 14 and FIG. 15, respectively. In measurement point 1, as shown in FIG. 14, the peaks of silicon and barium, which are the main components of nickel and glass particles, are included. In measurement point 2, as shown in FIG. 15, nickel and no peak of silicon and barium, which are the main components of the glass particles, are included. The peak could be confirmed. The metal-containing glass particles produced in this result are present in the particles in a state where metal nickel and glass are separated in one particle. That is, it turned out that metal nickel is glass particle contained in glass particle.

This invention is useful as a glass material which can be used for manufacture of an electronic component, etc.

When the glass particles of the present invention are used, when the glass particles are dispersed in a solvent, the glass particles suppress the movement of the metal particles, thereby preventing agglomeration of the metal particles and producing a slurry in which the glass particles and the metal particles are uniformly dispersed. have.

In addition, according to the method for producing glass particles of the present invention, the glass particles in which the metal particles are contained in advance are prepared by preparing raw material powders of the glass powder and the metal powder, and not requiring many processes such as mixing, melting, and pulverization. In a small process, high efficiency and low cost can be provided. Furthermore, there is no restriction | limiting in the kind of metal particle or the composition of glass particle, It is possible to provide the glass particle and glass particle aggregate which are rich in variation.

Claims (12)

Glass particles containing metal particles, wherein the surface of the metal particles is coated with an oxide film. The glass particle according to claim 1, wherein the oxide film contains a constituent element of the glass particle. The glass particle according to claim 1, wherein the oxide film contains at least one of silicon oxide, boron oxide, and phosphorus oxide. The glass particle according to claim 1, wherein the particle diameter of the glass particles is at least two times and not more than 200,000 times that of the metal particles contained therein. The glass particle according to claim 1, wherein a plurality of said metal particles are contained in a dispersed state. The glass particle according to claim 1, wherein the glass particles have a multilayer structure in which a plurality of glass layers made of different glass components are laminated outward from the center of the glass particles. It is a glass particle aggregate by which the glass particle of Claim 1 aggregates, The average particle diameter is 0.01 micrometer-10 micrometers, The glass particle aggregate characterized by the above-mentioned. It is a glass particle aggregate by which the glass particle of Claim 5 aggregates, The average particle diameter is 0.01 micrometer or more and 10 micrometers or less, The glass particle aggregate characterized by the above-mentioned. It is a glass particle aggregate by which the glass particle of Claim 6 aggregates, The average particle diameter is 0.01 micrometer or more and 10 micrometers or less, The glass particle aggregate characterized by the above-mentioned. It is a method for producing glass particles containing metal particles, Coating a surface of the metal particles to be contained with an oxide film; Mixing the metal particles coated on the surface with an oxide film in a solution containing a constituent element of glass to produce a raw material slurry; A method for producing glass particles, comprising the step of introducing the raw material slurry into droplets and introducing it into a high-temperature furnace body to thermally decompose. The method for producing glass particles according to claim 10, wherein the temperature of the thermal decomposition is higher than the glass glass transition temperature. The process of Claim 10 which mixes the obtained glass particle in the solution containing the said glass particle and another glass component, and prepares a raw material slurry, A method of producing glass particles, characterized by further comprising the step of introducing the resulting raw material slurry into droplets and introducing it into a high-temperature furnace body for thermal decomposition.

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