WO2013133357A1 - Spherical particle manufacturing method - Google Patents

Spherical particle manufacturing method Download PDF

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Publication number
WO2013133357A1
WO2013133357A1 PCT/JP2013/056239 JP2013056239W WO2013133357A1 WO 2013133357 A1 WO2013133357 A1 WO 2013133357A1 JP 2013056239 W JP2013056239 W JP 2013056239W WO 2013133357 A1 WO2013133357 A1 WO 2013133357A1
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Prior art keywords
liquid phase
phase
solid
solid phase
glass
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PCT/JP2013/056239
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French (fr)
Japanese (ja)
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拓朗 池田
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日本山村硝子株式会社
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Priority to JP2014503532A priority Critical patent/JP6099625B2/en
Publication of WO2013133357A1 publication Critical patent/WO2013133357A1/en

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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B33/00—Silicon; Compounds thereof
    • C01B33/113—Silicon oxides; Hydrates thereof
    • C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B33/00—Silicon; Compounds thereof
    • C01B33/113—Silicon oxides; Hydrates thereof
    • C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
    • C01B33/18—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B19/00—Other methods of shaping glass
    • C03B19/10—Forming beads
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B20/00—Processes specially adapted for the production of quartz or fused silica articles, not otherwise provided for
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C11/00—Multi-cellular glass ; Porous or hollow glass or glass particles
    • C03C11/005—Multi-cellular glass ; Porous or hollow glass or glass particles obtained by leaching after a phase separation step
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C12/00—Powdered glass; Bead compositions
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C15/00—Surface treatment of glass, not in the form of fibres or filaments, by etching
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/01—Particle morphology depicted by an image
    • C01P2004/03—Particle morphology depicted by an image obtained by SEM
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/51—Particles with a specific particle size distribution
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer

Definitions

  • the present invention relates to a method for producing spherical particles of an oxide, and more particularly to a method for producing spherical particles made of glass.
  • Glass particles are used in various fields as fillers and sintering aids, for example. Particles used for such applications are required to have various properties improved by controlling the particle size and shape, and especially those that are spherical and have a uniform particle size are also used as spacers and gap materials. .
  • Patent Document 1 discloses a high reliability having a high dielectric breakdown voltage characteristic in which both a high dielectric constant and a low dielectric loss are achieved by using SiO2 fine particles having a particle diameter of 0.1 ⁇ m or less as a sintering aid.
  • a multilayer ceramic capacitor is disclosed.
  • One method for producing a spherical glass powder is to spheroidize a powder produced by pulverizing a larger glass by heating.
  • this method it is difficult to obtain a powder having a uniform particle size by pulverization, and the particle size distribution of the powder is directly reflected in the particle size distribution of the final product. Classification is required and productivity is low.
  • Patent Documents 2 to 4 there is a method in which spherical particles are directly generated by a sol-gel method.
  • the sol-gel method it is relatively easy to obtain particles having a uniform particle size distribution, but it takes a long time for particle growth, and it is difficult to obtain dense particles having a relatively large particle size.
  • hydrothermal synthesis and flux methods are known as methods for producing particles from the liquid phase. These are methods for generating crystals in the liquid phase, and glass particles cannot be generated, and atomic planes that are easy to grow are determined based on the crystal structure. Since it grows into a unique shape, it is difficult to make it spherical.
  • phase separation phenomenon of glass is generally known in the Na 2 O—B 2 O 3 —SiO 2 system and the like.
  • an acid treatment is performed.
  • Non-patent Document 1 A method of obtaining a porous glass having pores of about several nm to several hundred nm by removing the soluble phase, or heating the porous glass to eliminate the pores to obtain 96 to 98% silica glass
  • a crystallized glass in which fine particles are dispersed in glass and the characteristics as a glass-fine particle composite are applied Non-patent Document 1).
  • JP 2004-319569 A Japanese Patent Publication No. 1-59975 Japanese Examined Patent Publication No. 4-15169 JP 2001-97735 A
  • the present invention provides a new production method for producing spherical glass particles, which is different from the above-described production method, and particularly enables production of spherical particles having a uniform particle size distribution in a short time. For the purpose.
  • the present inventor makes use of the liquid-liquid phase separation phenomenon to separate the uniform liquid phase A into the liquid phase B and the liquid phase C, and the spherical liquid phase C is separated into the liquid phase B.
  • This is cooled and solidified so that the spherical solid phase C is separated in the solid phase B, and then the solid glass B is dissolved in a solvent and removed to easily obtain spherical glass particles having a uniform particle size.
  • the present invention provides the following manufacturing method.
  • a melt which is a uniform composition comprising liquid phase A containing B 2 O 3 as a component, and causing liquid phase A to undergo phase separation to form a dispersion medium, liquid phase B and dispersoid
  • an emulsion which is a composition comprising a certain liquid phase C, and cooling the emulsion to solidify the liquid phase B and the liquid phase C into the corresponding glass solid phase B and solid phase C, respectively;
  • a solid dispersion system in which the solid phase C, which is a dispersoid, is dispersed in the solid phase B, which is a dispersion medium, is obtained, and the solid dispersion system is treated with a solvent for the solid phase B so that the solid phase is obtained.
  • a method for producing glass particles comprising: dissolving and removing B to recover the solid phase C. 2.
  • Preparing a melt which is a uniform composition comprising liquid phase A, comprising SiO 2 and B 2 O 3 , wherein the proportion of SiO 2 does not exceed 50 mol%;
  • Causing an emulsion which is a composition comprising liquid phase B as a dispersion medium and liquid phase C as a dispersoid, and cooling the emulsion so that liquid phase B and liquid phase C respectively correspond to glass
  • the solid phase C which is a dispersoid containing SiO 2 at a higher weight percentage than the solid phase B, is dispersed in the solid phase B, which is a dispersion medium.
  • the solid dispersion system having the above-described form, and the solid dispersion system is treated with a solvent for the solid phase B, the solid phase B is dissolved and removed, and the solid phase C is recovered.
  • a method for producing glass particles. 3. The manufacturing method of said 1 or 2 whose said solvent is water, an acid, or the aqueous solution of an acid. 4). 4. The production method according to any one of 1 to 3 above, wherein the liquid phase A contains an oxide of a divalent metal which may be an alkali metal oxide and / or an alkaline earth metal. 5. 5. The production method according to any one of 1 to 4 above, wherein the phase separation is performed by cooling the liquid phase A to a temperature in a temperature region not lower than the softening point and lower than the melting point.
  • the phase separation is carried out by once cooling the melt to a temperature below the softening point and then reheating it to a temperature in the temperature region above the softening point and below the melting point.
  • the liquid phase A contains an oxide of a divalent metal which may be an alkaline earth metal, and the solvent is an acid or an aqueous solution of the acid. 8).
  • the liquid phase A contains an alkali metal oxide and the solvent is water, an acid, or an aqueous solution of an acid. 9.
  • the composition of liquid phase A is SiO 2 : 5 to 50 mol% B 2 O 3 : 25 to 70 mol% R 1 2 O: 0 ⁇ 20mol % (R 1 comprehensively represents Li, Na, and K.) R 2 O: 0 to 50 mol% (R 2 comprehensively represents Mg, Ca, Sr, Ba and Zn.)
  • spherical glass particles having a uniform particle size distribution can be obtained in a shorter time than before. Furthermore, it is possible to obtain spherical glass particles having an average particle diameter of 0.01 to 100 ⁇ m and a CV value (standard deviation / average) of the particle diameter not exceeding 30%.
  • FIG. 1 is a drawing-substituting photograph showing an SEM observation image of the etched surface of the glass block of Example 1.
  • FIG. 2 is a drawing-substituting photograph showing an SEM observation image of particles separated from the glass of Example 2.
  • FIG. 3 is a drawing-substituting photograph showing an SEM observation image of particles separated from the glass of Example 21.
  • the liquid phase on the dispersoid side becomes a spherical shape having a uniform particle size, and when cooled and solidified as it is, the glass particles having a uniform particle size are dispersed. It utilizes the fact that a solid dispersion in a dispersed form can be obtained. Therefore, the present invention can be carried out using glasses having various compositions as long as phase separation occurs from a uniform melt and only the solid dispersion medium obtained can be dissolved and removed with a solvent.
  • liquid phase for the composition or a part thereof includes not only the case where they are at a temperature higher than the melting point, but also the case where they are in the temperature range above the softening point and lower than the melting point.
  • a uniform melt (liquid phase A) containing B 2 O 3 as one component is first prepared, and then phase separation is caused.
  • liquid phase A is divided into a continuous phase (liquid phase B) forming a dispersion medium and a dispersoid (liquid phase C) dispersed in the continuous phase, and an emulsion is formed as a whole.
  • This is cooled to solidify both phases (solid phases B and C, respectively) to form a solid dispersion system, and by dissolving and removing the dispersion medium (solid phase B), the solid phase C dispersed therein is removed. It can be obtained as glass particles.
  • SiO 2 and B 2 O 3 larger in weight percent and a uniform oxide mainly composed of an alkali metal oxide and / or a divalent metal oxide which may be an alkaline earth metal are used.
  • the resulting melt undergoes liquid-liquid phase separation due to a decrease in temperature, and the glass obtained by cooling and solidifying this is in a dispersion medium that is a solid phase (glass) containing SiO 2 at a relatively low weight percentage.
  • a solid dispersion system in which a dispersoid that is a spherical solid phase (glass) containing SiO 2 in a relatively high weight percent is dispersed, and this dispersion medium has a relatively low weight percent of SiO 2 ( Therefore, the weight percentage of B 2 O 3 is relatively high), so that only the dispersion medium can be removed by dissolving it in water, an acid or an aqueous solution of an acid, or in some cases, an aqueous solution of a base. Obtainable.
  • SiO 2 is a main component constituting a solid phase insoluble in acid. If the content of SiO 2 in the uniform liquid phase A obtained by melting the raw material is too large, the proportion of the insoluble phase becomes too large when the phases are separated, and the insoluble phase continues in a network form. Spherical particles cannot be obtained. Conversely, if the content of SiO 2 in the liquid phase A is too small, the yield of the insoluble phase will be low. Therefore, the content of SiO 2 in the liquid phase A (and therefore in the raw material) is preferably 5 to 50 mol%, more preferably 7 to 45 mol%, and still more preferably 10 to 42 mol%.
  • B 2 O 3 is a main component constituting a solid phase B that is soluble in a solvent.
  • the content of B 2 O 3 in the liquid phase A is preferably 25 to 70 mol%, more preferably 30 to 65 mol%, still more preferably 35 to 60 mol%. Note that when representing the content in% by weight, the content of B 2 O 3 in the liquid phase A is preferably greater than the content of SiO 2.
  • the liquid phase A can contain an alkaline earth metal oxide R 2 O.
  • the alkaline earth metal oxide is a component that is soluble in an acid or an aqueous solution of an acid and can be used to form a soluble solid phase B.
  • Alkaline earth metal oxides have low compatibility with SiO 2, and by containing alkaline earth metal oxides in the liquid phase A, the liquid phase A can be obtained under relatively high temperature (and therefore relatively low viscosity) conditions. The phase separation of the resulting particles is relatively large. Accordingly, alkaline earth metal oxides are suitable for inclusion in the liquid phase A as a component when it is desired to increase the particle size of the obtained particles (for example, 1 to 100 ⁇ m). When the alkaline earth metal oxide is contained in the liquid phase A, if it is too much, phase separation will not occur. Therefore, the content is preferably kept at 50 mol% or less.
  • the liquid phase A can contain an alkali metal oxide R 1 2 O.
  • Alkali metal oxides are components that are soluble in water, acids or aqueous solutions of acids (and even in aqueous solutions of bases) and can be used to form a soluble solid phase. is there. Inclusion of the alkali metal oxide in the liquid phase A brings about an effect of improving the dissolution rate of the soluble solid phase B.
  • the alkali metal oxide has a relatively high compatibility with SiO 2, and by containing the alkali metal oxide, the temperature at which the phase separation of the liquid phase A occurs is set to a relatively low temperature side (and thus a relatively high viscosity side).
  • the alkali metal oxide is suitable for being contained as a component in the liquid phase A when it is desired to reduce the particle size of the obtained particles (for example, 0.01 to 1 ⁇ m).
  • the ease of phase separation when the same amount of alkali metal oxide is contained in the liquid phase A is in the order of Li 2 O> Na 2 O> K 2 O.
  • the content is preferably kept at 20 mol% or less.
  • the content (R 1 2 O + R 2 O) is preferably 5 mol% or more, more preferably 8 mol% or more, and further preferably 10 mol% or more. Further, since the phase separation does not occur when the content is large, the content should be preferably 50 mol% or less, more preferably 40 mol% or less, and still more preferably 35 mol% or less.
  • the liquid phase A does not exceed 30 mol% of a trivalent or higher metal oxide (for example, Y 2 O 3 , TiO 2 , ZrO 2 , Al 2 O 3 , GeO 2, etc.). It can be contained in a range.
  • a trivalent or higher metal oxide for example, Y 2 O 3 , TiO 2 , ZrO 2 , Al 2 O 3 , GeO 2, etc.
  • Al 2 O 3 which is one of the optional components that can be contained in the liquid phase A, has the effect of increasing the compatibility between SiO 2 and B 2 O 3, and generates a uniform liquid phase A. Addition is beneficial in terms of ease. However, if the content of Al 2 O 3 in the liquid phase A is excessively increased, the phase separation becomes difficult, and the residual amount of SiO 2 in the solid phase B, which is a dispersion medium to be dissolved and removed, is reduced. Since inconvenience such as increase occurs, even when Al 2 O 3 is contained in the liquid phase A, it is limited to 30 mol% or less, preferably 20 mol% or less, more preferably 15 mo% or less, and further preferably 10 mol% or less. Should.
  • Liquid phase A may contain, as an optional component, a metal salt other than the above, or a metal salt such as a metal halide (fluoride, chloride, bromide or iodide). At least a part of these optional components in the liquid phase A is also contained in the insoluble solid phase C, and as a result, multicomponent spherical glass particles are obtained. This provides a means for adding new functions such as optical properties and catalytic properties to the glass particles through adjustment of the types and combinations of optional components to be contained and the amounts thereof.
  • the phase separation is performed in such a manner that the melt, which is a uniform composition composed of the liquid phase A in a state in which the raw materials are mixed at a high temperature, is melted into a temperature range above the softening point and below the melting point (hereinafter referred to as “phase separation temperature range”). It can also be caused by cooling to the temperature within.
  • the rate of cooling can be selected as appropriate.
  • the composition may be allowed to cool naturally from the melt state, and simply pass through the phase separation temperature region, and the composition may be within the phase separation temperature region.
  • the composition may be kept at a constant temperature for an appropriate time, and may be reheated to raise the temperature of the composition as long as it is within the phase separation temperature range. If the time during which the liquid phase A is kept in the phase separation temperature region is long, particle growth is promoted and the particle size is easily increased.
  • phase separation the composition is rapidly cooled from a uniform melt state to a temperature lower than the softening point (for example, room temperature), and then heated again to the phase separation temperature region and maintained in the phase separation temperature region for an appropriate time. Can also be awakened. Just by rapidly cooling from the melt state to a temperature below the softening point, the higher the cooling rate, the more difficult the phase separation occurs. Even if it occurs, the solidified product (glass) obtained in this way is negligible. By reheating to a temperature within the phase separation temperature region, phase separation can proceed, and generation of liquid phase C particles and particle growth can be promoted.
  • a temperature lower than the softening point for example, room temperature
  • the melt which is a uniform composition composed of the liquid phase A in a state where the raw materials are mixed at a high temperature, is cooled to a temperature within the phase separation temperature region to cause phase separation and then cooled (for example, to room temperature). ) And then solidified into glass, and then heated again to the phase separation temperature region at an appropriate time to further promote particle growth.
  • the time required for phase separation varies depending on the glass composition, the temperature during phase separation, and the target particle size.
  • particles of 1 ⁇ m to 100 ⁇ m can be produced by heat treatment for several minutes to several hours, and R 1 2 O—B 2 O 3 —SiO 2
  • particles of 0.1 ⁇ m to 1 ⁇ m can be produced by heat treatment for several hours.
  • the solvent that dissolves the dispersion medium of the solid dispersion system is not particularly limited as long as it is a solvent that dissolves only the dispersion medium without dissolving the dispersoid.
  • an acid or an aqueous solution of an acid it is preferable to select one that forms a salt with alkali metal or alkaline earth metal having high solubility in water.
  • suitable solvents for example, inorganic acids such as hydrochloric acid, nitric acid and sulfuric acid, various organic acids such as lactic acid, gluconic acid and citric acid or aqueous solutions of these acids can be used particularly preferably. However, hydrofluoric acid and its aqueous solution are excluded.
  • the dispersion medium contains a large amount of alkali metal oxide, water or even an aqueous solution of a base such as an alkali hydroxide can be used as the solvent.
  • Removal of particles from a solution in which particles obtained by treating a solid dispersion with a solvent are dispersed can be performed using an appropriate solid-liquid separation means such as filtration using a filter of an appropriate size or centrifugation. .
  • spherical glass particles composed of SiO 2 and containing a small amount of B 2 O 3 and having a uniform particle diameter can be produced in a short time.
  • spherical glass particles comprising 90 to 99 wt% of SiO 2 and 1 to 10 wt% of B 2 O 3 have an average particle diameter of preferably 0.01 to 100 ⁇ m, more preferably 0. 0.05 to 80 ⁇ m, particularly preferably 0.07 to 60 ⁇ m, and in each case, a CV value (standard deviation / average) of the particle size not exceeding 30% can be obtained.
  • the content of SiO 2 may be 92 to 99 wt%
  • the content of B 2 O 3 may be 1 to 8 wt%.
  • the present invention does not prevent the spherical glass particles from containing a small amount of Y 2 O 3 , GeO 2 , TiO 2 or the like (eg, 10 mol% or less, 8 mol%, 5 mol% or less, etc.).
  • Example 1 The raw materials mixed so as to give the composition of SiO 2 : 25, B 2 O 3 : 45, Al 2 O 3 : 2, CaO: 28 at mol% were melted at 1550 ° C. in a platinum crucible, and then the melt was Poured into a 50 mm ⁇ 50 mm ⁇ 10 mm mold and allowed to cool naturally. Phase separation occurred rapidly, and a solidified and cloudy glass block was obtained. As a result of performing powder X-ray diffraction on the glass block, it was amorphous.
  • the glass block was broken and the surface etched with a 2N HCl solution was observed with a scanning electron microscope (SEM), and the composition was analyzed with EDX (Energy Dispersive X-ray Spectroscopy). It was.
  • SEM observation formation of spherical glass particles was observed as shown in FIG.
  • O and Si were detected from spherical glass particles, but Ca and Al were not detected. Even if B is present at a few mol%, it cannot be detected, so it was found that the spherical glass particles are mainly composed of SiO 2 .
  • the average particle diameter (number average particle diameter) estimated from the SEM image was 2.4 ⁇ m and the standard deviation was 0.35 ⁇ m.
  • Example 2 The raw materials mixed so as to give the composition of SiO 2 : 25, B 2 O 3 : 45, Al 2 O 3 : 2, CaO: 28 at mol% were melted at 1550 ° C. in a platinum crucible, and then at the same temperature. It was transferred to a 300 cc crucible made of clay, held at 1300 ° C. for 4 hours, and then allowed to cool naturally. The crucible was crushed to obtain a cloudy glass block.
  • This glass block was dissolved in 2N HCl aqueous solution, filtered through a 0.5 ⁇ m filter, the filter was dried, and the residue on the filter was subjected to SEM observation and EDX analysis. As shown in FIG. 2, generation of spherical glass particles of SiO 2 was observed. The average particle size estimated from the SEM image was 16.2 ⁇ m and the standard deviation was 2.8 ⁇ m. As a result of performing powder X-ray diffraction on the spherical glass particles, it was confirmed to be amorphous.
  • Examples 3 to 11 In the same manner as in Examples 1 and 2 under the conditions described in Tables 1 and 2, the raw material was melted, phase-separated, solidified, dissolved, filtered, and dried to obtain spherical glass particles, which were subjected to SEM observation and EDX analysis. did.
  • Example 12 The raw materials mixed so as to give the composition of SiO 2 : 38, B 2 O 3 : 51, Na 2 O: 11 in mol% were melted at 1400 ° C. in a platinum crucible, then poured into a mold and allowed to cool naturally. A transparent glass block was obtained. This glass block was put in an alumina crucible, placed in a furnace heated to 720 ° C., softened, cooled to 520 ° C. over 10 hours, and then allowed to cool in the furnace to obtain a cloudy glass block. The glass block was dissolved in 80 ° C. water, filtered through a 0.1 ⁇ m filter, and dried to obtain spherical glass particles, which were similarly subjected to SEM observation and EDX analysis.
  • Examples 13 to 18 The same operations as in Examples 1 to 11 were performed under the conditions described in Tables 2 to 3, to obtain spherical glass particles, which were subjected to SEM observation and EDX analysis. In Examples 16 to 18, as shown in Table 2, it was confirmed that spherical glass particles containing Y 2 O 3 , GeO 2 , and TiO 2 were produced.
  • ICP Inductively Coupled
  • a solution for ICP emission spectroscopic analysis was prepared by dissolving 0.1 g of spherical glass particles and 2 g of potassium carbonate at 1200 ° C. and cooling the resulting solid in 100 ml of 1.5 N nitric acid. And diluted 20 times.
  • O and Si were detected from spherical glass particles, but Ca, Sr and Al were not detected. Therefore, as shown in Table 3, B 2 O 3 was contained in several wt%, and the remainder was mainly composed of SiO 2 . Turned out to be glass
  • Example 21 After the raw materials mixed so as to give the composition shown in Table 3 were melted at 1200 ° C. in a platinum crucible, the melt was quenched with a stainless steel cooling roll to produce a glass flake having a thickness of about 1 mm. . This glass flake was heat-treated under the conditions shown in the table to cause phase separation. This was analyzed by X-ray diffraction and confirmed to be amorphous. The continuous phase containing B 2 O 3 at a relatively high weight percent was dissolved in 2N hydrochloric acid at 80 ° C., the mixture was centrifuged to remove the spherical glass particles, washed and the particles recovered. The particle diameter was measured by SEM observation (FIG. 3).
  • the average particle size was 0.05 ⁇ m, and the standard deviation was 0.02 ⁇ m.
  • the particles were examined for glass transition point, yield point, and softening point by DTA. That is, about 15 mg of each glass composition powder sample was placed in a platinum cell, and using a differential thermal analyzer (type name “TG-8120”, manufactured by Rigaku Corporation), alumina powder was used as a standard sample in the atmosphere. Below, a DTA curve was obtained at a temperature increase rate of 20 ° C./min from room temperature to 1150 ° C. The first endothermic peak start point (extrapolated point) was the glass transition point, the endothermic minimum temperature was the yield point, and the second endothermic peak start point (extrapolated point) was the glass softening point.
  • the present invention is useful as a method for efficiently producing spherical glass particles having a uniform particle size distribution.

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Abstract

A glass particle manufacturing method comprises: preparing a molten liquid that is a uniform composition consisting of a liquid phase A which contains B2O3 as one component; producing an emulsion that is a composition consisting of a liquid phase B which is a dispersion medium and a liquid phase C which is a dispersoid caused by phase separation in the liquid phase A; cooling the emulsion to solidify the liquid phase B and the liquid phase C into a solid phase B and a solid phase C that are glass respectively corresponding to the liquid phase B and the liquid phase C, thereby obtaining a solid dispersed system in which the solid phase C which is a dispersoid is dispersed in the solid phase B which is a dispersion medium; and treating the solid dispersed system with a solvent with respect to the solid phase B to dissolve and remove the solid phase B and recover the solid phase C.

Description

球状粒子の製造方法Method for producing spherical particles
　本発明は酸化物の球状粒子を製造する方法に関し，より詳しくは，ガラスからなる球状粒子を製造する方法に関する。 The present invention relates to a method for producing spherical particles of an oxide, and more particularly to a method for producing spherical particles made of glass.
　ガラス粒子は，例えば，フィラーや焼結助剤として種々の分野で使用されている。そのような用途に用いる粒子としては，粒径や形状を制御して各種特性を向上したものが求められており，特に，球状で粒径の揃ったものは，スペーサーやギャップ材としても用いられる。 Glass particles are used in various fields as fillers and sintering aids, for example. Particles used for such applications are required to have various properties improved by controlling the particle size and shape, and especially those that are spherical and have a uniform particle size are also used as spacers and gap materials. .
　また，セラミックコンデンサの分野でも焼結助剤等としてガラス粒子は用いられているが，特に同分野では近年，コンデンサの小型化，高機能化を達成するために粒子径の小さいガラスが用いられている。例えば，特許文献１には，粒子径が０．１μｍ以下のＳｉＯ２微粒子を焼結助剤として用いることで高い誘電率と低い誘電損失とを両立させた，高い絶縁破壊電圧特性を有する高信頼性の積層セラミックコンデンサが開示されている。 In the ceramic capacitor field, glass particles are used as sintering aids. In particular, glass with a small particle diameter has recently been used in this field in order to achieve miniaturization and higher functionality of capacitors. Yes. For example, Patent Document 1 discloses a high reliability having a high dielectric breakdown voltage characteristic in which both a high dielectric constant and a low dielectric loss are achieved by using SiO2 fine particles having a particle diameter of 0.1 μm or less as a sintering aid. A multilayer ceramic capacitor is disclosed.
　球状のガラス粉末の製造方法の１つとして，より大きなガラスを粉砕して製造した粉末を加熱により球状化させる方法がある。しかしながら，この方法では，粉砕で粒度の揃った粉末を得ることは困難であり，粉末の粒度分布が最終製品の粒度分布にそのまま反映されるため，粒度分布の揃った球状粒子を得るには精密な分級が必要となり，生産性が低い。他の方法として，ゾル－ゲル法により直接に球状粒子を生成させる方法がある（特許文献２～４）。ゾル－ゲル法においては，粒度分布の揃った粒子を得ることは比較的容易にできるものの，粒子成長に長時間かかり，粒径が比較的大きく緻密な粒子を得ることは困難である。 One method for producing a spherical glass powder is to spheroidize a powder produced by pulverizing a larger glass by heating. However, with this method, it is difficult to obtain a powder having a uniform particle size by pulverization, and the particle size distribution of the powder is directly reflected in the particle size distribution of the final product. Classification is required and productivity is low. As another method, there is a method in which spherical particles are directly generated by a sol-gel method (Patent Documents 2 to 4). In the sol-gel method, it is relatively easy to obtain particles having a uniform particle size distribution, but it takes a long time for particle growth, and it is difficult to obtain dense particles having a relatively large particle size.
　また，液相からの粒子の生成方法として水熱合成法やフラックス法が知られている。これらは液相中に結晶を生成させる方法であって，ガラス粒子を生成させることはできず，また，結晶構造に基づいて成長しやすい原子面が決まっており，柱状や八面体などのその結晶特有の形状に成長するため，球状の粒子にさせることは困難である。 Also, hydrothermal synthesis and flux methods are known as methods for producing particles from the liquid phase. These are methods for generating crystals in the liquid phase, and glass particles cannot be generated, and atomic planes that are easy to grow are determined based on the crystal structure. Since it grows into a unique shape, it is difficult to make it spherical.
　その他，一般的にＮａ２Ｏ－Ｂ２Ｏ３－ＳｉＯ２系などでガラスの相分離現象が知られている。ガラスの相分離現象を応用した技術として，酸に溶解性の相（Ｎａ２Ｏ－Ｂ２Ｏ３）と不溶性の相(ＳｉＯ２)とが複雑に絡み合ったガラス作った後，酸処理して溶解性の相を除去し，数ｎｍ～数百ｎｍ程度の細孔を持つ多孔質ガラスを得る方法や，該多孔質ガラスを加熱して細孔を消失させて９６～９８％のシリカガラスを得る方法，及び他にも，ガラス中に微粒子を分散させてガラス－微粒子複合体としての特性を応用した結晶化ガラスが知られている（非特許文献１）。 In addition, the phase separation phenomenon of glass is generally known in the Na 2 O—B 2 O 3 —SiO 2 system and the like. As a technology applying the phase separation phenomenon of glass, after making a glass in which an acid-soluble phase (Na 2 O—B 2 O 3 ) and an insoluble phase (SiO 2 ) are intertwined, an acid treatment is performed. A method of obtaining a porous glass having pores of about several nm to several hundred nm by removing the soluble phase, or heating the porous glass to eliminate the pores to obtain 96 to 98% silica glass In addition to the method to obtain, there is known a crystallized glass in which fine particles are dispersed in glass and the characteristics as a glass-fine particle composite are applied (Non-patent Document 1).
特開２００４－３１９５６９号公報JP 2004-319569 A 特公平１－５９９７５号公報Japanese Patent Publication No. 1-59975 特公平４－１５１６９号公報Japanese Examined Patent Publication No. 4-15169 特開２００１－９７７３５号公報JP 2001-97735 A
　本発明は球状ガラス粒子の製造のための，上述の製造方法とは異なる新たな製造方法であって，特に粒度分布の揃った球状粒子を短時間で得ることを可能にする製造方法を提供することを目的とする。 The present invention provides a new production method for producing spherical glass particles, which is different from the above-described production method, and particularly enables production of spherical particles having a uniform particle size distribution in a short time. For the purpose.
　本発明者は液－液相分離現象を利用し，均一な液相Ａを液相Ｂと液相Ｃとに相分離させ，液相Ｂの中に球状の液相Ｃが分離した状態とし，これを冷却して固化させ，固相Ｂの中に球状の固相Ｃが分離した状態とした後，固相Ｂを溶媒に溶解し取り除くことで粒径の揃った球状のガラス粒子を簡便に製造できることを見出した。また特に，Ｒ２Ｏ－Ｂ２Ｏ３－ＳｉＯ２系の場合にはガラス粒子の成長を早め，１μｍ以上にまで成長させることができることを見出した。すなわち本発明は，以下の製造方法を提供するものである。 The present inventor makes use of the liquid-liquid phase separation phenomenon to separate the uniform liquid phase A into the liquid phase B and the liquid phase C, and the spherical liquid phase C is separated into the liquid phase B. This is cooled and solidified so that the spherical solid phase C is separated in the solid phase B, and then the solid glass B is dissolved in a solvent and removed to easily obtain spherical glass particles having a uniform particle size. We found that it can be manufactured. In particular, it has been found that in the case of the R 2 O—B 2 O 3 —SiO 2 system, the growth of glass particles can be accelerated and grown to 1 μm or more. That is, the present invention provides the following manufacturing method.
　１．Ｂ２Ｏ３を一成分として含有する液相Ａからなる均一な組成物である融液を調製することと，液相Ａに相分離を起こさせて分散媒である液相Ｂと分散質である液相Ｃとからなる組成物であるエマルジョンを生成させることと，該エマルジョンを冷却して液相Ｂ及び液相Ｃをそれぞれ対応するガラスである固相Ｂ及び固相Ｃへと固化させ，それにより分散媒である該固相Ｂ中に分散質である該固相Ｃが分散した形態の固体分散系を得ることと，該固体分散系を該固相Ｂに対する溶媒で処理し該固相Ｂを溶解除去して該固相Ｃを回収することとを含んでなる，ガラス粒子の製造方法。
　２．ＳｉＯ２とＢ２Ｏ３を含んでなりＳｉＯ２の割合が５０ｍｏｌ％を超えないものである液相Ａからなる均一な組成物である融液を調製することと，液相Ａに相分離を起こさせて分散媒である液相Ｂと分散質である液相Ｃとからなる組成物であるエマルジョンを生成させることと，該エマルジョンを冷却して液相Ｂ及び液相Ｃをそれぞれ対応するガラスである固相Ｂ及び固相Ｃへと固化させ，それにより分散媒である該固相Ｂ中に該固相Ｂより高い重量％でＳｉＯ２を含有する分散質である該固相Ｃが分散した形態の固体分散系を得ることと，該固体分散系を該固相Ｂに対する溶媒で処理し該固相Ｂを溶解除去して該固相Ｃを回収することとを含んでなる，上記１のガラス粒子の製造方法。
　３．該溶媒が，水，酸，又は酸の水溶液である，上記１又は２の製造方法。
　４．該液相Ａがアルカリ金属酸化物，及び／又はアルカリ土類金属であってよい２価金属の酸化物を含むものである，上記１～３の何れかの製造方法。
　５．該相分離が，軟化点以上且つ融点未満の温度領域内の温度まで液相Ａを冷却することにより行われるものである，上記１～４の何れかの製造方法。
　６．該相分離が，該融液を軟化点未満の温度まで一旦冷却した後，軟化点以上且つ融点未満の温度領域内の温度まで再加熱することにより行われるものである，上記１～４の何れかの製造方法。
　７．液相Ａがアルカリ土類金属であってよい２価金属の酸化物を含み，該溶媒が酸，又は酸の水溶液である，上記１～６の何れかの製造方法。
　８．液相Ａがアルカリ金属酸化物を含み，該溶媒が水，酸，又は酸の水溶液である，上記１～７の何れかの製造方法。
　９．該ガラス粒子の平均粒径が０．０１～１００μｍである，上記１～８の何れかの製造方法。
　１０．該ガラス粒子の平均粒径が０．１μｍ～３０μｍである，上記１～８の何れかの製造方法。
　１１．液相Ａの組成が，
ＳｉＯ２：５～５０ｍｏｌ％
Ｂ２Ｏ３：２５～７０ｍｏｌ％
Ｒ１ ２Ｏ：０～２０ｍｏｌ％
（Ｒ１は，Ｌｉ，Ｎａ及びＫを包括的に表す。）
Ｒ２Ｏ：０～５０ｍｏｌ％
（Ｒ２は，Ｍｇ，Ｃａ，Ｓｒ，Ｂａ及びＺｎを包括的に表す。）
を含んでなり，但し，Ｒ１ ２Ｏ又はＲ２Ｏの何れかを含有するものである，上記１～１０の何れかの製造方法。
　１２．Ｂ２Ｏ３を１～１０ｗｔ％及びＳｉＯ２を９０～９９ｗｔ％含んでなり，平均粒径が０．０１～１００μｍであり，粒径のＣＶ値（標準偏差／平均）が３０％を超えないことを特徴とする，球形ガラス粒子。 1. Preparing a melt, which is a uniform composition comprising liquid phase A containing B 2 O 3 as a component, and causing liquid phase A to undergo phase separation to form a dispersion medium, liquid phase B and dispersoid Producing an emulsion which is a composition comprising a certain liquid phase C, and cooling the emulsion to solidify the liquid phase B and the liquid phase C into the corresponding glass solid phase B and solid phase C, respectively; Thereby, a solid dispersion system in which the solid phase C, which is a dispersoid, is dispersed in the solid phase B, which is a dispersion medium, is obtained, and the solid dispersion system is treated with a solvent for the solid phase B so that the solid phase is obtained. A method for producing glass particles, comprising: dissolving and removing B to recover the solid phase C.
2. Preparing a melt, which is a uniform composition comprising liquid phase A, comprising SiO 2 and B 2 O 3 , wherein the proportion of SiO 2 does not exceed 50 mol%; Causing an emulsion which is a composition comprising liquid phase B as a dispersion medium and liquid phase C as a dispersoid, and cooling the emulsion so that liquid phase B and liquid phase C respectively correspond to glass The solid phase C, which is a dispersoid containing SiO 2 at a higher weight percentage than the solid phase B, is dispersed in the solid phase B, which is a dispersion medium. The solid dispersion system having the above-described form, and the solid dispersion system is treated with a solvent for the solid phase B, the solid phase B is dissolved and removed, and the solid phase C is recovered. A method for producing glass particles.
3. The manufacturing method of said 1 or 2 whose said solvent is water, an acid, or the aqueous solution of an acid.
4). 4. The production method according to any one of 1 to 3 above, wherein the liquid phase A contains an oxide of a divalent metal which may be an alkali metal oxide and / or an alkaline earth metal.
5. 5. The production method according to any one of 1 to 4 above, wherein the phase separation is performed by cooling the liquid phase A to a temperature in a temperature region not lower than the softening point and lower than the melting point.
6). The phase separation is carried out by once cooling the melt to a temperature below the softening point and then reheating it to a temperature in the temperature region above the softening point and below the melting point. Manufacturing method.
7). 7. The production method according to any one of 1 to 6 above, wherein the liquid phase A contains an oxide of a divalent metal which may be an alkaline earth metal, and the solvent is an acid or an aqueous solution of the acid.
8). 8. The production method according to any one of 1 to 7 above, wherein the liquid phase A contains an alkali metal oxide and the solvent is water, an acid, or an aqueous solution of an acid.
9. 9. The production method according to any one of 1 to 8 above, wherein the glass particles have an average particle size of 0.01 to 100 μm.
10. 9. The production method according to any one of 1 to 8 above, wherein the glass particles have an average particle size of 0.1 μm to 30 μm.
11. The composition of liquid phase A is
SiO 2 : 5 to 50 mol%
B 2 O 3 : 25 to 70 mol%
R 1 2 O: 0 ~ 20mol %
(R 1 comprehensively represents Li, Na, and K.)
R 2 O: 0 to 50 mol%
(R 2 comprehensively represents Mg, Ca, Sr, Ba and Zn.)
The process according to any one of 1 to 10 above, wherein the process comprises any one of R 1 2 O and R 2 O.
12 It contains 1 to 10 wt% B 2 O 3 and 90 to 99 wt% SiO 2, has an average particle size of 0.01 to 100 μm, and the particle size CV value (standard deviation / average) does not exceed 30% Spherical glass particles characterized by that.
　本発明によれば，粒度分布の揃った球状ガラス粒子を従来に比べ短時間で得ることが可能となる。更に，平均粒径が０．０１～１００μｍで粒径のＣＶ値（標準偏差／平均）が３０％を超えない球状ガラス粒子を得ることが可能となる。 According to the present invention, spherical glass particles having a uniform particle size distribution can be obtained in a shorter time than before. Furthermore, it is possible to obtain spherical glass particles having an average particle diameter of 0.01 to 100 μm and a CV value (standard deviation / average) of the particle diameter not exceeding 30%.
図１は，実施例１のガラスブロックをエッチングした表面のＳＥＭ観察像を示す図面代用写真である。FIG. 1 is a drawing-substituting photograph showing an SEM observation image of the etched surface of the glass block of Example 1. 図２は，実施例２のガラスから分離した粒子のＳＥＭ観察像を示す図面代用写真である。FIG. 2 is a drawing-substituting photograph showing an SEM observation image of particles separated from the glass of Example 2. 図３は，実施例２１のガラスから分離した粒子のＳＥＭ観察像を示す図面代用写真である。FIG. 3 is a drawing-substituting photograph showing an SEM observation image of particles separated from the glass of Example 21.
　本発明は，均一な融液から液相－液相分離させたとき，分散質側の液相が粒径の揃った球状となり，そのまま冷却し固化すれば粒径の揃ったガラス粒子が分散媒中に分散した形の固体分散系が得られる，ということを利用したものである。従って，本発明は，均一な融液から相分離が生じ且つ得られる固体分散系の分散媒のみを溶媒で溶解除去できるものである限り，種々の組成のガラスを用いて行うことができる。 In the present invention, when the liquid phase and the liquid phase are separated from a uniform melt, the liquid phase on the dispersoid side becomes a spherical shape having a uniform particle size, and when cooled and solidified as it is, the glass particles having a uniform particle size are dispersed. It utilizes the fact that a solid dispersion in a dispersed form can be obtained. Therefore, the present invention can be carried out using glasses having various compositions as long as phase separation occurs from a uniform melt and only the solid dispersion medium obtained can be dissolved and removed with a solvent.
　本明細書において，組成物又はその部分について「液相」というときは，それらが融点以上の温度にある場合のみならず，軟化点以上融点未満の温度範囲にある場合も含む。 In the present specification, the term “liquid phase” for the composition or a part thereof includes not only the case where they are at a temperature higher than the melting point, but also the case where they are in the temperature range above the softening point and lower than the melting point.
　特に，本発明においては，Ｂ２Ｏ３を一成分として含む均一な融液（液相Ａ）を先ず調製し，次いでこれに相分離を起こさせる。相分離によって，液相Ａは，分散媒をなす連続相（液相Ｂ）と，この連続相中に分散された分散質（液相Ｃ）とに分かれ，全体としてエマルジョンが形成されるから，これを冷却して両相を固化させて（それぞれ，固相Ｂ及びＣ）固体分散系とし，分散媒（固相Ｂ）を溶解除去することで，その中に分散されていた固相Ｃをガラス粒子として得ることができる。 In particular, in the present invention, a uniform melt (liquid phase A) containing B 2 O 3 as one component is first prepared, and then phase separation is caused. By phase separation, liquid phase A is divided into a continuous phase (liquid phase B) forming a dispersion medium and a dispersoid (liquid phase C) dispersed in the continuous phase, and an emulsion is formed as a whole. This is cooled to solidify both phases (solid phases B and C, respectively) to form a solid dispersion system, and by dissolving and removing the dispersion medium (solid phase B), the solid phase C dispersed therein is removed. It can be obtained as glass particles.
　また本発明において，例えば，ＳｉＯ２及び重量％においてこれより多いＢ２Ｏ３と，アルカリ金属酸化物及び／又はアルカリ土類金属であってよい２価金属の酸化物とを主成分とする均一な融液は，温度の低下による液－液相分離を起こし，これを冷却固化して得られるガラスは，ＳｉＯ２を相対的に低い重量％で含有する固相（ガラス）である分散媒中に，ＳｉＯ２を相対的に高い重量％で含有する球状の固相（ガラス）である分散質が分散した
固体分散系であり，この分散媒は，ＳｉＯ２の重量％が相対的に低い（従って，Ｂ２Ｏ３の重量％が相対的に高い）ため，分散媒のみを水，酸又は酸の水溶液，又は場合により塩基の水溶液に溶解させて除去でき，分散質である球状ガラス粒子を得ることができる。 Further, in the present invention, for example, SiO 2 and B 2 O 3 larger in weight percent and a uniform oxide mainly composed of an alkali metal oxide and / or a divalent metal oxide which may be an alkaline earth metal are used. The resulting melt undergoes liquid-liquid phase separation due to a decrease in temperature, and the glass obtained by cooling and solidifying this is in a dispersion medium that is a solid phase (glass) containing SiO 2 at a relatively low weight percentage. In addition, a solid dispersion system in which a dispersoid that is a spherical solid phase (glass) containing SiO 2 in a relatively high weight percent is dispersed, and this dispersion medium has a relatively low weight percent of SiO 2 ( Therefore, the weight percentage of B 2 O 3 is relatively high), so that only the dispersion medium can be removed by dissolving it in water, an acid or an aqueous solution of an acid, or in some cases, an aqueous solution of a base. Obtainable.
　本発明におけるガラスの組成について，以下により詳しく説明する。
　ＳｉＯ２は酸に対して不溶性の固相を構成する主成分である。原料を溶融させて得られる均一な液相Ａ中のＳｉＯ２の含有量が多過ぎると，相分離させたときに不溶性の相の割合が多くなり過ぎ，不溶性相が網目状に連続してしまい，球状粒子を得ることはできない。逆に液相Ａ中のＳｉＯ２の含有量が少な過ぎると，不溶性の相の収率が低くなってしまう。このため，液相Ａ中の（従って，原料中の）ＳｉＯ２の含有量は，好ましくは，５～５０ｍｏｌ％，より好ましくは７～４５ｍｏｌ％，更に好ましくは１０～４２ｍｏｌ％である。 The composition of the glass in the present invention will be described in more detail below.
SiO 2 is a main component constituting a solid phase insoluble in acid. If the content of SiO 2 in the uniform liquid phase A obtained by melting the raw material is too large, the proportion of the insoluble phase becomes too large when the phases are separated, and the insoluble phase continues in a network form. Spherical particles cannot be obtained. Conversely, if the content of SiO 2 in the liquid phase A is too small, the yield of the insoluble phase will be low. Therefore, the content of SiO 2 in the liquid phase A (and therefore in the raw material) is preferably 5 to 50 mol%, more preferably 7 to 45 mol%, and still more preferably 10 to 42 mol%.
　Ｂ２Ｏ３は，溶媒に溶解性の固相Ｂを構成する主成分である。液相Ａ中のＢ２Ｏ３の含有量は好ましくは２５～７０ｍｏｌ％，より好ましくは３０～６５ｍｏｌ％，更に好ましくは３５～６０ｍｏｌ％である。なお，重量％で含有量を表した場合，液相Ａ中のＢ２Ｏ３の含有量は，好ましくは，ＳｉＯ２の含有量より多い。 B 2 O 3 is a main component constituting a solid phase B that is soluble in a solvent. The content of B 2 O 3 in the liquid phase A is preferably 25 to 70 mol%, more preferably 30 to 65 mol%, still more preferably 35 to 60 mol%. Note that when representing the content in% by weight, the content of B 2 O 3 in the liquid phase A is preferably greater than the content of SiO 2.
　必須成分ではないが，液相Ａにアルカリ土類金属酸化物Ｒ２Ｏを含有させておくことができる。アルカリ土類金属酸化物は，酸又は酸の水溶液に対し溶解性を示し，溶解性の固相Ｂを構成するのに用いることのできる成分である。アルカリ土類金属酸化物はＳｉＯ２との相溶性が低く，アルカリ土類金属酸化物を液相Ａに含有させておくことで，比較的高温（従って，比較的低粘性）条件で液相Ａの相分離を起こさせることができ，そのため，得られる粒子の粒径が比較的大きくなる。従って，アルカリ土類金属酸化物は得られる粒子の粒径を大きくしたい場合（例えば１～１００μｍ）に液相Ａに成分として含有させておくのに適している。なお，液相Ａにアルカリ土類金属酸化物を含有させておく場合，多過ぎると相分離を起こさなくなってしまうため，その含有量は，５０ｍｏｌ％以下に止めておくことが好ましい。 Although not an essential component, the liquid phase A can contain an alkaline earth metal oxide R 2 O. The alkaline earth metal oxide is a component that is soluble in an acid or an aqueous solution of an acid and can be used to form a soluble solid phase B. Alkaline earth metal oxides have low compatibility with SiO 2, and by containing alkaline earth metal oxides in the liquid phase A, the liquid phase A can be obtained under relatively high temperature (and therefore relatively low viscosity) conditions. The phase separation of the resulting particles is relatively large. Accordingly, alkaline earth metal oxides are suitable for inclusion in the liquid phase A as a component when it is desired to increase the particle size of the obtained particles (for example, 1 to 100 μm). When the alkaline earth metal oxide is contained in the liquid phase A, if it is too much, phase separation will not occur. Therefore, the content is preferably kept at 50 mol% or less.
　必須成分ではないが，液相Ａにアルカリ金属酸化物Ｒ１ ２Ｏを含有させておくことができる。アルカリ金属酸化物は，水，酸又は酸の水溶液に対して（更には，塩基の水溶液に対してさえも）溶解性を示し，溶解性の固相を構成するのに用いることのできる成分である。アルカリ金属酸化物を液相Ａに含有させておくことは，溶解性の固相Ｂの溶解速度を向上させる効果をもたらす。また，アルカリ金属酸化物はＳｉＯ２との相溶性が比較的高く，アルカリ金属酸化物を含有させることで液相Ａの相分離の起きる温度を比較的低温側（従って比較的高粘性側）にシフトさせることができ，それにより，得られる粒子の粒径が小さくなる。従って，アルカリ金属酸化物は，得られる粒子の粒径を小さくしたい場合（例えば０．０１～１μｍ）に液相Ａに成分として含有させておくのに適している。なお，アルカリ金属酸化物のうち，同量を液相Ａに含有させた場合の相分離の起こし易さは，Ｌｉ２Ｏ＞Ｎａ２Ｏ＞Ｋ２Ｏの順である。なお，液相Ａにアルカリ金属酸化物を含有させておく場合，多すぎると相分離を起こさなくなってしまうため，その含有量は，２０ｍｏｌ％以下に止めておくことが好ましい。 Although it is not an essential component, the liquid phase A can contain an alkali metal oxide R 1 2 O. Alkali metal oxides are components that are soluble in water, acids or aqueous solutions of acids (and even in aqueous solutions of bases) and can be used to form a soluble solid phase. is there. Inclusion of the alkali metal oxide in the liquid phase A brings about an effect of improving the dissolution rate of the soluble solid phase B. In addition, the alkali metal oxide has a relatively high compatibility with SiO 2, and by containing the alkali metal oxide, the temperature at which the phase separation of the liquid phase A occurs is set to a relatively low temperature side (and thus a relatively high viscosity side). Can be shifted, thereby reducing the particle size of the resulting particles. Accordingly, the alkali metal oxide is suitable for being contained as a component in the liquid phase A when it is desired to reduce the particle size of the obtained particles (for example, 0.01 to 1 μm). Note that the ease of phase separation when the same amount of alkali metal oxide is contained in the liquid phase A is in the order of Li 2 O> Na 2 O> K 2 O. In addition, when the alkali metal oxide is contained in the liquid phase A, if it is too much, phase separation does not occur. Therefore, the content is preferably kept at 20 mol% or less.
　なお，アルカリ土類金属酸化物とアルカリ金属酸化物は，何れも必須成分ではないが，少なくとも何れか一方を液相Ａに含有させておくことが好ましい。その場合，これらの含有量（Ｒ１ ２Ｏ＋Ｒ２Ｏ）は，好ましくは５ｍｏｌ％以上，より好ましくは８ｍｏｌ％以上，更に好ましくは１０ｍｏｌ％以上である。また,含有量が多いと相分離を起こさなくなってしまうため，その含有量は好ましくは５０ｍｏｌ％以下，より好ましくは４０ｍｏｌ％以下，更に好ましくは３５ｍｏｌ％以下に止めるべきである。 In addition, although neither an alkaline-earth metal oxide nor an alkali metal oxide is an essential component, it is preferable to contain at least one of them in the liquid phase A. In that case, the content (R 1 2 O + R 2 O) is preferably 5 mol% or more, more preferably 8 mol% or more, and further preferably 10 mol% or more. Further, since the phase separation does not occur when the content is large, the content should be preferably 50 mol% or less, more preferably 40 mol% or less, and still more preferably 35 mol% or less.
　また，必須成分ではないが，液相Ａに，３価以上の金属の酸化物（例えば，Ｙ２Ｏ３，ＴｉＯ２，ＺｒＯ２，Ａｌ２Ｏ３，ＧｅＯ２等）を３０ｍｏｌ％を超えない範囲で含有させておくことができる。 Further, although not an essential component, the liquid phase A does not exceed 30 mol% of a trivalent or higher metal oxide (for example, Y 2 O 3 , TiO 2 , ZrO 2 , Al 2 O 3 , GeO 2, etc.). It can be contained in a range.
　液相Ａに含有させておくことができる任意成分の１つであるＡｌ２Ｏ３は，ＳｉＯ２とＢ２Ｏ３との相溶性を高める効果を有し，均一な液相Ａを生成させ易くする点で添加は有益である。しかし，液相Ａ中のＡｌ２Ｏ３の含有量を多くし過ぎると相分離が困難になり，また溶解されて除去されることになる分散媒である固相Ｂ中のＳｉＯ２残留量が多くなる等の不都合が生じるため，Ａｌ２Ｏ３を液相Ａに含有させておく場合も，３０ｍｏｌ％以下，好ましくは２０ｍｏｌ％以下，より好ましくは１５ｍｏ％以下，更に好ましくは１０ｍｏｌ％以下に止めるべきである。 Al 2 O 3, which is one of the optional components that can be contained in the liquid phase A, has the effect of increasing the compatibility between SiO 2 and B 2 O 3, and generates a uniform liquid phase A. Addition is beneficial in terms of ease. However, if the content of Al 2 O 3 in the liquid phase A is excessively increased, the phase separation becomes difficult, and the residual amount of SiO 2 in the solid phase B, which is a dispersion medium to be dissolved and removed, is reduced. Since inconvenience such as increase occurs, even when Al 2 O 3 is contained in the liquid phase A, it is limited to 30 mol% or less, preferably 20 mol% or less, more preferably 15 mo% or less, and further preferably 10 mol% or less. Should.
　液相Ａに，任意成分として，上記以外の金属酸化物や，ハロゲン化金属（フッ化，塩化，臭化又はヨウ化金属）等の金属塩を含有させてもよい。液相Ａ中のそれら任意成分の少なくとも一部は，不溶性の固相Ｃに側にも含有されることになり，その結果，多成分の球状ガラス粒子が得られる。このことは，含有させる任意成分の種類や組み合わせ，及びそれらの量の調節を通じて，ガラス粒子に新たな光学特性や触媒特性等の機能を付加するための手段を提供する。 Liquid phase A may contain, as an optional component, a metal salt other than the above, or a metal salt such as a metal halide (fluoride, chloride, bromide or iodide). At least a part of these optional components in the liquid phase A is also contained in the insoluble solid phase C, and as a result, multicomponent spherical glass particles are obtained. This provides a means for adding new functions such as optical properties and catalytic properties to the glass particles through adjustment of the types and combinations of optional components to be contained and the amounts thereof.
　本発明において，相分離は，原料を高温で相溶させた状態の液相Ａからなる均一な組成物である融液を，軟化点以上且つ融点未満の温度領域（以下，「相分離温度領域」ともいう。）内の温度にまで冷却することによって起こさせることができる。冷却の速度は適宜選択でき，例えば，組成物を融液の状態から自然放冷することにより，相分離温度領域を単に通過させるだけでもよく，また，相分離温度領域内において，組成物をある一定温度で適宜の時間保持してもよく，更には，相分離温度領域内である限り，再加熱して組成物の温度を高めてもよい。液相Ａを相分離温度領域におく時間を長くとると，粒子の成長が促され，粒径を増大させ易い。 In the present invention, the phase separation is performed in such a manner that the melt, which is a uniform composition composed of the liquid phase A in a state in which the raw materials are mixed at a high temperature, is melted into a temperature range above the softening point and below the melting point (hereinafter referred to as “phase separation temperature range”). It can also be caused by cooling to the temperature within. The rate of cooling can be selected as appropriate. For example, the composition may be allowed to cool naturally from the melt state, and simply pass through the phase separation temperature region, and the composition may be within the phase separation temperature region. The composition may be kept at a constant temperature for an appropriate time, and may be reheated to raise the temperature of the composition as long as it is within the phase separation temperature range. If the time during which the liquid phase A is kept in the phase separation temperature region is long, particle growth is promoted and the particle size is easily increased.
　相分離はまた，組成物を均一な融液の状態から軟化点未満の温度（例えば，室温）まで一旦急冷した後，再度相分離温度領域まで加熱して適宜の時間相分離温度領域内に保持することによっても，起こさせることができる。融液の状態から軟化点未満の温度まで急冷しただけでは，冷却速度が速い程相分離は起こり難く，たとえ起こってもごく僅かであるが，そのようにして得られた固化物（ガラス）を，相分離温度領域内の温度まで再加熱することで，相分離を進行させ，液相Ｃの粒子の発生と粒子の成長とを促すことができる。 In phase separation, the composition is rapidly cooled from a uniform melt state to a temperature lower than the softening point (for example, room temperature), and then heated again to the phase separation temperature region and maintained in the phase separation temperature region for an appropriate time. Can also be awakened. Just by rapidly cooling from the melt state to a temperature below the softening point, the higher the cooling rate, the more difficult the phase separation occurs. Even if it occurs, the solidified product (glass) obtained in this way is negligible. By reheating to a temperature within the phase separation temperature region, phase separation can proceed, and generation of liquid phase C particles and particle growth can be promoted.
　相分離にはまた，上述の２通りの方法の組み合わせを用いてもよい。すなわち，原料を高温で相溶させた状態の液相Ａからなる均一な組成物である融液を，相分離温度領域内の温度にまで冷却して相分離起こさせ，次いで冷却（例えば室温まで）して固化させてガラスとしたものを，その後適宜の時期に，再度相分離温度領域まで加熱して粒子の成長を更に促してもよい。 For the phase separation, a combination of the above two methods may also be used. That is, the melt, which is a uniform composition composed of the liquid phase A in a state where the raw materials are mixed at a high temperature, is cooled to a temperature within the phase separation temperature region to cause phase separation and then cooled (for example, to room temperature). ) And then solidified into glass, and then heated again to the phase separation temperature region at an appropriate time to further promote particle growth.
　相分離に要する時間は，ガラス組成，相分離時の温度，目標とする粒径によって異なる。Ｒ２Ｏ－Ｂ２Ｏ３－ＳｉＯ２系の液相Ａでは，数分～数時間の熱処理で１μｍ～１００μｍの粒子を作製することができ，Ｒ１ ２Ｏ－Ｂ２Ｏ３－ＳｉＯ２系の液相Ａでは数時間の熱処理で０．１μｍ～１μｍの粒子を作製することができる。 The time required for phase separation varies depending on the glass composition, the temperature during phase separation, and the target particle size. In the liquid phase A based on R 2 O—B 2 O 3 —SiO 2 , particles of 1 μm to 100 μm can be produced by heat treatment for several minutes to several hours, and R 1 2 O—B 2 O 3 —SiO 2 In the liquid phase A of the system, particles of 0.1 μm to 1 μm can be produced by heat treatment for several hours.
　固体分散系の分散媒を溶解させる溶媒については，分散質を溶解させずに分散媒のみを溶解させる溶媒であればよく，それ以外に特に限定はない。溶媒として酸又は酸の水溶液を用いる場合，アルカリ金属やアルカリ土類金属と水に対する溶解度の高い塩を形成するものを選ぶのが好ましい。適した溶媒として，例えば，塩酸，硝酸，硫酸等の無機酸や，乳酸，グルコン酸，クエン酸等の種々の有機酸又はそれらの酸の水溶液を特に好適に用いることができる。但しフッ酸やその水溶液は除く。また，分散媒がアルカリ金属酸化物を多く含有する場合には，水を，更には水酸化アルカリ等の塩基の水溶液でさえも，溶媒として用いることができる。 The solvent that dissolves the dispersion medium of the solid dispersion system is not particularly limited as long as it is a solvent that dissolves only the dispersion medium without dissolving the dispersoid. When an acid or an aqueous solution of an acid is used as the solvent, it is preferable to select one that forms a salt with alkali metal or alkaline earth metal having high solubility in water. As suitable solvents, for example, inorganic acids such as hydrochloric acid, nitric acid and sulfuric acid, various organic acids such as lactic acid, gluconic acid and citric acid or aqueous solutions of these acids can be used particularly preferably. However, hydrofluoric acid and its aqueous solution are excluded. When the dispersion medium contains a large amount of alkali metal oxide, water or even an aqueous solution of a base such as an alkali hydroxide can be used as the solvent.
　固体分散系を溶媒で処理して得られる粒子が分散した溶液からの粒子の取り出しは，適当なサイズのフィルタを用いたろ過や遠心分離等，適宜の固液分離手段を用いて行うことができる。 Removal of particles from a solution in which particles obtained by treating a solid dispersion with a solvent are dispersed can be performed using an appropriate solid-liquid separation means such as filtration using a filter of an appropriate size or centrifugation. .
　本発明によれば，主としてＳｉＯ２からなりＢ２Ｏ３を少量含有してよい，粒子径の良好に揃った球状ガラス粒子を短時間で製造することができる。特に本発明によれば，ＳｉＯ２を９０～９９ｗｔ％及びＢ２Ｏ３を１～１０ｗｔ％含んでなる球状ガラス粒子であって，平均粒径が好ましくは０．０１～１００μｍ，より好ましくは０．０５～８０μｍ，特に好ましくは０．０７～６０μｍであり，且つ，各場合において粒径のＣＶ値（標準偏差／平均）が３０％を超えないものを得ることができる。例えば，ＳｉＯ２の含有量を９２～９９ｗｔ％，Ｂ２Ｏ３の含有量を１～８ｗｔ％としてもよい。なお，本発明は，球状ガラス粒子が，Ｙ２Ｏ３，ＧｅＯ２，及びＴｉＯ２等を少量（例えば１０ｍｏｌ％以下，８ｍｏｌ％，５ｍｏｌ％以下等）含有することは妨げない。 According to the present invention, spherical glass particles composed of SiO 2 and containing a small amount of B 2 O 3 and having a uniform particle diameter can be produced in a short time. In particular, according to the present invention, spherical glass particles comprising 90 to 99 wt% of SiO 2 and 1 to 10 wt% of B 2 O 3 have an average particle diameter of preferably 0.01 to 100 μm, more preferably 0. 0.05 to 80 μm, particularly preferably 0.07 to 60 μm, and in each case, a CV value (standard deviation / average) of the particle size not exceeding 30% can be obtained. For example, the content of SiO 2 may be 92 to 99 wt%, and the content of B 2 O 3 may be 1 to 8 wt%. The present invention does not prevent the spherical glass particles from containing a small amount of Y 2 O 3 , GeO 2 , TiO 2 or the like (eg, 10 mol% or less, 8 mol%, 5 mol% or less, etc.).
　以下，実施例を参照して本発明を更に具体的に説明するが，本発明がそれら実施例に限定されることは意図しない。 Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not intended to be limited to these examples.
〔実施例１〕
　ｍｏｌ％でＳｉＯ２：２５，Ｂ２Ｏ３：４５，Ａｌ２Ｏ３：２，ＣａＯ：２８の組成を与えるように混合した原料を白金坩堝にて１５５０℃で溶融させた後，融液を５０ｍｍ×５０ｍｍ×１０ｍｍの鋳型に流し込み，自然放冷した。速やかに相分離が起こり，固化して白濁したガラスブロックを得た。ガラスブロックについて粉末Ｘ線回折を行った結果，非晶質であった。 [Example 1]
The raw materials mixed so as to give the composition of SiO 2 : 25, B 2 O 3 : 45, Al 2 O 3 : 2, CaO: 28 at mol% were melted at 1550 ° C. in a platinum crucible, and then the melt was Poured into a 50 mm × 50 mm × 10 mm mold and allowed to cool naturally. Phase separation occurred rapidly, and a solidified and cloudy glass block was obtained. As a result of performing powder X-ray diffraction on the glass block, it was amorphous.
　このガラスブロックを破断し，２ＮのＨＣｌ水溶液でエッチングした表面について走査型電子顕微鏡（ＳＥＭ）で観察すると共に，ＥＤＸ（Energy Dispersive X-ray Spectroscopy，エネルギー分散型Ｘ線分光法）で組成分析を行った。ＳＥＭ観察では，図１に示すように，球状ガラス粒子の生成が認められた。ＥＤＸにて，球状ガラス粒子からはＯ，Ｓｉが検出され，Ｃａ，Ａｌは検出されなかった。Ｂは数ｍｏｌ％程度では存在したとしても検出不能であるため,球状ガラス粒子はＳｉＯ２を主成分とすることが判明した。ＳＥＭ像から見積もった平均粒径（個数平均粒径）は２．４μｍ，標準偏差０．３５μｍであった。 The glass block was broken and the surface etched with a 2N HCl solution was observed with a scanning electron microscope (SEM), and the composition was analyzed with EDX (Energy Dispersive X-ray Spectroscopy). It was. In SEM observation, formation of spherical glass particles was observed as shown in FIG. In EDX, O and Si were detected from spherical glass particles, but Ca and Al were not detected. Even if B is present at a few mol%, it cannot be detected, so it was found that the spherical glass particles are mainly composed of SiO 2 . The average particle diameter (number average particle diameter) estimated from the SEM image was 2.4 μm and the standard deviation was 0.35 μm.
〔実施例２〕
　ｍｏｌ％でＳｉＯ２：２５，Ｂ２Ｏ３：４５，Ａｌ２Ｏ３：２，ＣａＯ：２８の組成を与えるように混合した原料を白金坩堝にて１５５０℃で溶融させた後，同温度で粘土製の３００ｃｃの坩堝に移し替え，１３００℃で４時間保持し，その後自然放冷した。坩堝を破砕し，白濁したガラスブロックを得た。 [Example 2]
The raw materials mixed so as to give the composition of SiO 2 : 25, B 2 O 3 : 45, Al 2 O 3 : 2, CaO: 28 at mol% were melted at 1550 ° C. in a platinum crucible, and then at the same temperature. It was transferred to a 300 cc crucible made of clay, held at 1300 ° C. for 4 hours, and then allowed to cool naturally. The crucible was crushed to obtain a cloudy glass block.
　このガラスブロックを２ＮのＨＣｌ水溶液に溶解させた後，０．５μｍのフィルタでろ過し，フィルタを乾燥させ，フィルタ上の残存物をＳＥＭ観察及びＥＤＸ分析に付した。図２に示すように，ＳｉＯ２の球状ガラス粒子の生成が認められた。ＳＥＭ像から見積もった粒径は平均１６．２μｍ，標準偏差２．８μｍであった。球状ガラス粒子について粉末Ｘ線回折を行った結果，非晶質であることが確認された。 This glass block was dissolved in 2N HCl aqueous solution, filtered through a 0.5 μm filter, the filter was dried, and the residue on the filter was subjected to SEM observation and EDX analysis. As shown in FIG. 2, generation of spherical glass particles of SiO 2 was observed. The average particle size estimated from the SEM image was 16.2 μm and the standard deviation was 2.8 μm. As a result of performing powder X-ray diffraction on the spherical glass particles, it was confirmed to be amorphous.
〔実施例３～１１〕
　表１～２に記載の条件で，実施例１，２と同様に，原料の溶融，相分離，固化，溶解，ろ過，乾燥を行ってそれぞれ球状ガラス粒子を得，ＳＥＭ観察及びＥＤＸ分析に付した。 [Examples 3 to 11]
In the same manner as in Examples 1 and 2 under the conditions described in Tables 1 and 2, the raw material was melted, phase-separated, solidified, dissolved, filtered, and dried to obtain spherical glass particles, which were subjected to SEM observation and EDX analysis. did.
〔実施例１２〕
　ｍｏｌ％でＳｉＯ２：３８，Ｂ２Ｏ３：５１，Ｎａ２Ｏ：１１の組成を与えるように混合した原料を白金坩堝にて１４００℃で溶融させた後，型に流し込み，自然放冷したところ，透明なガラスブロックを得た。このガラスブロックをアルミナ製坩堝に入れ，７２０℃に加熱した炉内に入れて軟化状態とし，１０時間かけて５２０℃まで冷却した後，炉内放冷し，白濁したガラスブロックを得た。このガラスブロックを８０℃の水に溶解させた後，０．１μｍのフィルタでろ過し，乾燥させて球状ガラス粒子を得，これを同様にＳＥＭ観察及びＥＤＸ分析に付した。 Example 12
The raw materials mixed so as to give the composition of SiO 2 : 38, B 2 O 3 : 51, Na 2 O: 11 in mol% were melted at 1400 ° C. in a platinum crucible, then poured into a mold and allowed to cool naturally. A transparent glass block was obtained. This glass block was put in an alumina crucible, placed in a furnace heated to 720 ° C., softened, cooled to 520 ° C. over 10 hours, and then allowed to cool in the furnace to obtain a cloudy glass block. The glass block was dissolved in 80 ° C. water, filtered through a 0.1 μm filter, and dried to obtain spherical glass particles, which were similarly subjected to SEM observation and EDX analysis.
〔実施例１３～１８〕
　表２～３に記載の条件で実施例１～１１と同様の作業を行い，それぞれ球状ガラス粒子を得，これをＳＥＭ観察及びＥＤＸ分析に付した。実施例１６～１８については，表２に示す通り，それぞれ，Ｙ２Ｏ３，ＧｅＯ２，及びＴｉＯ２を含有する球状ガラス粒子の生成が確認された。 [Examples 13 to 18]
The same operations as in Examples 1 to 11 were performed under the conditions described in Tables 2 to 3, to obtain spherical glass particles, which were subjected to SEM observation and EDX analysis. In Examples 16 to 18, as shown in Table 2, it was confirmed that spherical glass particles containing Y 2 O 3 , GeO 2 , and TiO 2 were produced.
〔実施例１９～２０〕
　表３に記載の条件で実施例１～１１と同様の作業を行った。また相分離した状態のガラスの一部（５ｇ）を酸に完全に溶解させ，遠心分離を行って球状ガラス粒子を取り出し，洗浄，乾燥後のそれらの粒子の重量を測定して，次の式により球状ガラス粒子の収率を求めた：
　収率＝粒子の重量／溶解に用いたガラスの重量（５ｇ）
　また, 得られた球状ガラス粒子中について，ＩＣＰ（Inductively Coupled
Plasma）発光分光分析によりＢ２Ｏ３の定量も行った。ＩＣＰ発光分光分析用の溶液は，球状ガラス粒子０．１ｇと炭酸カリウム２ｇを１２００℃で溶融し冷却して得た固体を１．５Ｎの硝酸１００ｍｌに溶解させた後，得られた溶液を水で２０倍に希釈することにより調製した。ＥＤＸにて，球状ガラス粒子からはＯ，Ｓｉが検出され，Ｃａ，Ｓｒ，Ａｌは検出されなかったため，表３に示すようにＢ２Ｏ３を数ｗｔ％含み，残りはＳｉＯ２を主成分とするガラスであると判明した [Examples 19 to 20]
The same operations as in Examples 1 to 11 were performed under the conditions described in Table 3. In addition, a part (5 g) of the phase-separated glass is completely dissolved in acid, centrifuged to take out spherical glass particles, and the weight of those particles after washing and drying is measured. The yield of spherical glass particles was determined by:
Yield = particle weight / glass used for melting (5 g)
In addition, about the obtained spherical glass particles, ICP (Inductively Coupled)
Plasma) emission by spectroscopic analysis of B 2 O 3 quantitation was performed. A solution for ICP emission spectroscopic analysis was prepared by dissolving 0.1 g of spherical glass particles and 2 g of potassium carbonate at 1200 ° C. and cooling the resulting solid in 100 ml of 1.5 N nitric acid. And diluted 20 times. In EDX, O and Si were detected from spherical glass particles, but Ca, Sr and Al were not detected. Therefore, as shown in Table 3, B 2 O 3 was contained in several wt%, and the remainder was mainly composed of SiO 2 . Turned out to be glass
〔実施例２１〕
　表３に記載の組成を与えるように混合した原料を白金坩堝にて１２００℃で溶融させた後，融液をステンレススチール製の冷却ロールにて急冷し，厚さ約１ｍｍのガラスフレークを作製した。このガラスフレークを表に示した条件で熱処理して，相分離を起こさせた。これをＸ線回折により分析し，非晶質であることを確認した。Ｂ２Ｏ３を相対的に高い重量％で含有する連続相を２Ｎ塩酸で８０℃にで溶解させ，混合物を遠心分離に付して球状ガラス粒子を取り出し，洗浄して粒子を回収した。ＳＥＭ観察により粒子径を測定した（図３）。平均粒径（個数平均粒径）は０．０５μｍ，標準偏差は０．０２μｍであった。また，粒子についてＤＴＡによりガラス転移点，屈伏点，軟化点を調べた。すなわち，各ガラス組成物の粉末状試料の約１５ｍｇを白金セルに入れ，示差熱分析装置（型名「ＴＧ－８１２０」，（株）リガク製）を用いて，アルミナ粉末を標準試料として大気雰囲気下において室温から１１５０℃まで２０℃／分の昇温速度でＤＴＡ曲線を得た。最初の吸熱ピークの開始点（外挿点）をガラス転移点とし，その吸熱の極小値の温度を屈伏点とし，第二の吸熱ピークの開始点（外挿点）をガラス軟化点とした。 Example 21
After the raw materials mixed so as to give the composition shown in Table 3 were melted at 1200 ° C. in a platinum crucible, the melt was quenched with a stainless steel cooling roll to produce a glass flake having a thickness of about 1 mm. . This glass flake was heat-treated under the conditions shown in the table to cause phase separation. This was analyzed by X-ray diffraction and confirmed to be amorphous. The continuous phase containing B 2 O 3 at a relatively high weight percent was dissolved in 2N hydrochloric acid at 80 ° C., the mixture was centrifuged to remove the spherical glass particles, washed and the particles recovered. The particle diameter was measured by SEM observation (FIG. 3). The average particle size (number average particle size) was 0.05 μm, and the standard deviation was 0.02 μm. The particles were examined for glass transition point, yield point, and softening point by DTA. That is, about 15 mg of each glass composition powder sample was placed in a platinum cell, and using a differential thermal analyzer (type name “TG-8120”, manufactured by Rigaku Corporation), alumina powder was used as a standard sample in the atmosphere. Below, a DTA curve was obtained at a temperature increase rate of 20 ° C./min from room temperature to 1150 ° C. The first endothermic peak start point (extrapolated point) was the glass transition point, the endothermic minimum temperature was the yield point, and the second endothermic peak start point (extrapolated point) was the glass softening point.
Figure JPOXMLDOC01-appb-T000001
  
Figure JPOXMLDOC01-appb-T000001
  
Figure JPOXMLDOC01-appb-T000002
  
Figure JPOXMLDOC01-appb-T000002
  
Figure JPOXMLDOC01-appb-T000003
  
Figure JPOXMLDOC01-appb-T000003
  
　本発明は，粒度分布の揃った球状ガラス粒子を効率的に製造する方法として，有用である。 The present invention is useful as a method for efficiently producing spherical glass particles having a uniform particle size distribution.

Claims (12)

  1. 　Ｂ２Ｏ３を一成分として含有する液相Ａからなる均一な組成物である融液を調製することと，液相Ａに相分離を起こさせて分散媒である液相Ｂと分散質である液相Ｃとからなる組成物であるエマルジョンを生成させることと，該エマルジョンを冷却して液相Ｂ及び液相Ｃをそれぞれ対応するガラスである固相Ｂ及び固相Ｃへと固化させ，それにより分散媒である該固相Ｂ中に分散質である該固相Ｃが分散した形態の固体分散系を得ることと，該固体分散系を該固相Ｂに対する溶媒で処理し該固相Ｂを溶解除去して該固相Ｃを回収することとを含んでなる，ガラス粒子の製造方法。 Preparing a melt, which is a uniform composition comprising liquid phase A containing B 2 O 3 as a component, and causing liquid phase A to undergo phase separation to form a dispersion medium, liquid phase B and dispersoid Producing an emulsion which is a composition comprising a certain liquid phase C, and cooling the emulsion to solidify the liquid phase B and the liquid phase C into the corresponding glass solid phase B and solid phase C, respectively; Thereby, a solid dispersion system in which the solid phase C, which is a dispersoid, is dispersed in the solid phase B, which is a dispersion medium, is obtained, and the solid dispersion system is treated with a solvent for the solid phase B so that the solid phase is obtained. A method for producing glass particles, comprising: dissolving and removing B to recover the solid phase C.
  2. 　ＳｉＯ２とＢ２Ｏ３を含んでなりＳｉＯ２の割合が５０ｍｏｌ％を超えないものである液相Ａからなる均一な組成物である融液を調製することと，液相Ａに相分離を起こさせて分散媒である液相Ｂと分散質である液相Ｃとからなる組成物であるエマルジョンを生成させることと，該エマルジョンを冷却して液相Ｂ及び液相Ｃをそれぞれ対応するガラスである固相Ｂ及び固相Ｃへと固化させ，それにより分散媒である該固相Ｂ中に該固相Ｂより高い重量％でＳｉＯ２を含有する分散質である該固相Ｃが分散した形態の固体分散系を得ることと，該固体分散系を該固相Ｂに対する溶媒で処理し該固相Ｂを溶解除去して該固相Ｃを回収することとを含んでなる，請求項１のガラス粒子の製造方法。 Preparing a melt, which is a uniform composition comprising liquid phase A, comprising SiO 2 and B 2 O 3 , wherein the proportion of SiO 2 does not exceed 50 mol%; Causing an emulsion which is a composition comprising liquid phase B as a dispersion medium and liquid phase C as a dispersoid, and cooling the emulsion so that liquid phase B and liquid phase C respectively correspond to glass The solid phase C, which is a dispersoid containing SiO 2 at a higher weight percentage than the solid phase B, is dispersed in the solid phase B, which is a dispersion medium. And obtaining the solid dispersion C by treating the solid dispersion with a solvent for the solid phase B, dissolving and removing the solid phase B, and recovering the solid phase C. The manufacturing method of 1 glass particle.
  3. 　該溶媒が，水，酸，又は酸の水溶液である，請求項１又は２の製造方法。 The production method according to claim 1 or 2, wherein the solvent is water, an acid, or an aqueous solution of an acid.
  4. 　該液相Ａがアルカリ金属酸化物，及び／又はアルカリ土類金属であってよい２価金属の酸化物を含むものである，請求項１～３の何れかの製造方法。 The production method according to any one of claims 1 to 3, wherein the liquid phase A contains an oxide of a divalent metal which may be an alkali metal oxide and / or an alkaline earth metal.
  5. 　該相分離が，軟化点以上且つ融点未満の温度領域内の温度まで液相Ａを冷却することにより行われるものである，請求項１～４の何れかの製造方法。 The production method according to any one of claims 1 to 4, wherein the phase separation is performed by cooling the liquid phase A to a temperature in a temperature region not lower than the softening point and lower than the melting point.
  6. 　該相分離が，該融液を軟化点未満の温度まで一旦冷却した後，軟化点以上且つ融点未満の温度領域内の温度まで再加熱することにより行われるものである，請求項１～４の何れかの製造方法。 The phase separation is carried out by once cooling the melt to a temperature below the softening point and then reheating it to a temperature in the temperature region above the softening point and below the melting point. Any manufacturing method.
  7. 　液相Ａがアルカリ土類金属であってよい２価金属の酸化物を含み，該溶媒が酸，又は酸の水溶液である，請求項１～６の何れかの製造方法。 The production method according to any one of claims 1 to 6, wherein the liquid phase A contains an oxide of a divalent metal which may be an alkaline earth metal, and the solvent is an acid or an aqueous solution of the acid.
  8. 　液相Ａがアルカリ金属酸化物を含み，該溶媒が水，酸，又は酸の水溶液である，請求項１～７の何れかの製造方法。 The process according to any one of claims 1 to 7, wherein the liquid phase A contains an alkali metal oxide and the solvent is water, an acid, or an aqueous solution of an acid.
  9. 　該ガラス粒子の平均粒径が０．０１～１００μｍである，請求項１～８の何れかの製造方法。 The production method according to any one of claims 1 to 8, wherein the average particle diameter of the glass particles is 0.01 to 100 µm.
  10. 　該ガラス粒子の平均粒径が０．１μｍ～３０μｍである，請求項１～８の何れかの製造方法。 The method according to any one of claims 1 to 8, wherein the glass particles have an average particle size of 0.1 to 30 µm.
  11. 　液相Ａの組成が，
    ＳｉＯ２：５～５０ｍｏｌ％
    Ｂ２Ｏ３：２５～７０ｍｏｌ％
    Ｒ１ ２Ｏ：０～２０ｍｏｌ％
    （Ｒ１は，Ｌｉ，Ｎａ及びＫを包括的に表す。）
    Ｒ２Ｏ：０～５０ｍｏｌ％
    （Ｒ２は，Ｍｇ，Ｃａ，Ｓｒ，Ｂａ及びＺｎを包括的に表す。）
    を含んでなり，但し，Ｒ１ ２Ｏ又はＲ２Ｏの何れかを含有するものである，請求項１～１０の何れかの製造方法。     The composition of liquid phase A is
    SiO 2 : 5 to 50 mol%
    B 2 O 3 : 25 to 70 mol%
    R 1 2 O: 0 ~ 20mol %
    (R 1 comprehensively represents Li, Na, and K.)
    R 2 O: 0 to 50 mol%
    (R 2 comprehensively represents Mg, Ca, Sr, Ba and Zn.)
    The process according to any one of claims 1 to 10, wherein the process comprises any one of R 1 2 O and R 2 O.
  12. 　Ｂ２Ｏ３を１～１０ｗｔ％及びＳｉＯ２を９０～９９ｗｔ％含んでなり，平均粒径が０．０１～１００μｍであり，粒径のＣＶ値（標準偏差／平均）が３０％を超えないことを特徴とする，球形ガラス粒子。 It contains 1 to 10 wt% B 2 O 3 and 90 to 99 wt% SiO 2, has an average particle size of 0.01 to 100 μm, and the particle size CV value (standard deviation / average) does not exceed 30% Spherical glass particles characterized by that.
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014058054A1 (en) * 2012-10-12 2014-04-17 旭硝子株式会社 Manufacturing method for phase-separated glass, and phase-separated glass
JP2015051887A (en) * 2013-09-05 2015-03-19 日本山村硝子株式会社 Method for manufacturing glass fine particle and glass fine particle
CN110002725A (en) * 2019-04-18 2019-07-12 中国建筑材料科学研究总院有限公司 The preparation method of porous glass beads, the porous glass beads by this method preparation and its application
CN110078376A (en) * 2019-04-18 2019-08-02 中国建筑材料科学研究总院有限公司 The preparation method of porous glass material, the porous glass material by this method preparation and its application

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58140341A (en) * 1982-02-15 1983-08-20 Agency Of Ind Science & Technol Production of high silicate porous glass
JPS6033230A (en) * 1983-08-04 1985-02-20 Fuji Debuison Kagaku Kk Process and apparatus for producing porous glass
JPS6479030A (en) * 1987-09-22 1989-03-24 Asahi Glass Co Ltd Production of porous small glass sphere

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6140838A (en) * 1984-07-31 1986-02-27 Nippon Chem Ind Co Ltd:The Sio2-b2o3 series glass and its manufacture
JPH10324539A (en) * 1997-05-22 1998-12-08 Asahi Glass Co Ltd Fine spherical glass and its production
JP2010254574A (en) * 2006-06-19 2010-11-11 Nihon Yamamura Glass Co Ltd Spherical multicomponent glass fine particle
JP2011068507A (en) * 2009-09-24 2011-04-07 Nihon Yamamura Glass Co Ltd Spherical multicomponent glass fine particle

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58140341A (en) * 1982-02-15 1983-08-20 Agency Of Ind Science & Technol Production of high silicate porous glass
JPS6033230A (en) * 1983-08-04 1985-02-20 Fuji Debuison Kagaku Kk Process and apparatus for producing porous glass
JPS6479030A (en) * 1987-09-22 1989-03-24 Asahi Glass Co Ltd Production of porous small glass sphere

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014058054A1 (en) * 2012-10-12 2014-04-17 旭硝子株式会社 Manufacturing method for phase-separated glass, and phase-separated glass
JPWO2014058054A1 (en) * 2012-10-12 2016-09-05 旭硝子株式会社 Method for producing phase-separated glass and phase-separated glass
US9580353B2 (en) 2012-10-12 2017-02-28 Asahi Glass Company, Limited Manufacturing method for phase-separated glass, and phase-separated glass
US9902647B2 (en) 2012-10-12 2018-02-27 Asahi Glass Company, Limited Manufacturing method for phase-separated glass, and phase-separated glass
JP2015051887A (en) * 2013-09-05 2015-03-19 日本山村硝子株式会社 Method for manufacturing glass fine particle and glass fine particle
CN110002725A (en) * 2019-04-18 2019-07-12 中国建筑材料科学研究总院有限公司 The preparation method of porous glass beads, the porous glass beads by this method preparation and its application
CN110078376A (en) * 2019-04-18 2019-08-02 中国建筑材料科学研究总院有限公司 The preparation method of porous glass material, the porous glass material by this method preparation and its application
CN110002725B (en) * 2019-04-18 2021-11-23 中国建筑材料科学研究总院有限公司 Preparation method of porous glass beads, porous glass beads prepared by method and application of porous glass beads

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