JP2006256895A - Glass microballoon and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide glass microballoons having a very small particle size and excellent water resistance and suited for addition to polymeric materials such as coating materials and resins. <P>SOLUTION: The glass microballoons have a glass composition of SiO<SB>2</SB>: 60-80 mass%, Na<SB>2</SB>O: 2-12.5 mass%, CaO: 5-15 mass%, B<SB>2</SB>O<SB>3</SB>: 4-15 mass%, and SO<SB>3</SB>: 0.05-1 mass%, provided that B<SB>2</SB>O<SB>3</SB>/Na<SB>2</SB>O (mass ratio)=1.2-3.5, have D90≤30 μm and D50≤10 μm in a particle size distribution as measured by a laser scattering particle size measurement, and have a particle density of 0.8-1.2 g/cm<SP>3</SP>. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a glass microhollow having an extremely small particle size, excellent water resistance, and excellent dispersion stability in a polymer material such as a paint or resin, and a method for producing the same.

  Glass hollow bodies are generally called glass balloons and glass bubbles, and are added to various materials taking advantage of their low specific gravity, fineness, and relatively high strength. Therefore, it is used for weight reduction and heat insulation performance. As an example of the field in which glass micro hollow bodies are used, it has spread to a wide range of applications such as paints and members for mobile bodies such as automobiles, ships, aircraft, putty, resin molding materials, various building materials, paper clay, etc. .

  In recent years, weight reduction of various materials for moving bodies has been desired, and in particular, glass micro-hollow bodies are uniformly dispersed without being broken in polymer materials such as paints and resin materials. It is desired that a polymer material such as a resin material has uniform physical properties at any part.

On the other hand, several patents have been filed for glass hollow bodies. Patent Document 1 discloses a glass microhollow body manufactured by using a borosilicate glass powder containing SO ₃ as a foaming component as a raw material and passing the raw glass powder through a flame. This glass microhollow body has a particle density equivalent to 0.5 g / cm ³ and a compressive strength (hydrostatic pressure at which the volume is reduced by 10%) is equivalent to 1400 kg / cm ² . However, such a glass microhollow body has an average particle diameter of 40 to 50 μm, and contains a large amount of coarse particles having a passing cumulative ratio 90% (D90) of 80 μm in the particle size distribution.

Patent Document 2 discloses a glass microhollow body having a particle density of 0.3 to 0.4 g / cm ³ and a compressive strength of 600 kg / cm ^{2 or} equivalent. However, the glass micro hollow body in this case has not only insufficient pressure resistance, but also has an average particle diameter of 45 μm and a particle diameter of D90 of 65 μm, which contains many coarse particles.

Further, Patent Document 3 discloses that a glass micro hollow body having a small particle diameter has a particle density of 0.485 g / cm ³ , a pressure strength of 660 kg / cm ² , an average particle diameter of 9.5 μm, and a D90 particle diameter of 24 μm. A glass micro hollow body is disclosed. However, the glass micro hollow body of Patent Document 3 is obtained by classifying a foamed product obtained by foaming a glass frit as a raw material with a sieve. Therefore, it is not economical in terms of yield and sieving operation.

Further, in the case of the conventional glass micro hollow body as described above, when the glass micro hollow body is added to the polymer material, the dispersion in the polymer material is not always smooth. There is a phenomenon in which the material is not uniformly dispersed but is included in an uneven manner. As a result, the polymer material containing the obtained glass microhollow body does not have uniform physical properties. There is also a demand for improved surface smoothness of added polymer materials and addition to fine material parts.
JP 58-156551 A Japanese Patent Laid-Open No. 4-202025 International Publication WO01 / 002314

  In view of the above-described prior art, when the glass micro-hollow body is added to the polymer material, the present invention allows the dispersion in the polymer material to be smoothly and uniformly dispersed. A glass microhollow body that has uniform physical properties, can be added to fine material parts, and improves the surface smoothness of the material, and a method for producing the glass microhollow body with a high yield The purpose is to provide.

As a result of diligent research, the present inventor has found that the above object can be achieved by imparting a specific composition, a specific particle size distribution, and a specific particle density to a glass microhollow body. did.
Thus, the present invention resides in a novel glass microhollow body having the following gist and a method for producing the same.
₍₁₎ SiO 2: 60~80 _wt%, Na 2 O: _2~12.5 wt%, CaO: 5 to 15 _{wt%, B} 2 O 3: _4~15 wt% and _SO 3: 0.05 to It has a composition of glass containing 1% by mass and B ₂ O ₃ / Na ₂ O (mass ratio) of 1.2 to 3.5, and D90 is 30 μm or less in the particle size distribution by laser scattering particle size measurement. D50 is 10 μm or less, and the particle density is 0.8 to 1.2 g / cm ³ .
(2) The glass micro hollow body according to (1), wherein the alkali elution degree is 0.08 meq / g or less.
(3) The glass micro hollow body according to (1) or (2), wherein the D90 is 20 μm or less, the D50 is 2 to 7 μm, and the particle density is 0.9 to 1.1 g / cm ^3. .
(4) The glass microhollow body according to any one of (1) to (3), wherein the glass microhollow body is used as a filler for a polymer material.
₍₅₎ SiO 2: 58~75 _wt%, Na 2 O: _3~12.5 wt%, CaO: 5 to 15 _{wt%, B} 2 O 3: _8~15 wt% and _SO 3: 0.05 to D90 is 20 μm or less in a particle size distribution by laser scattering particle size measurement, having a composition containing 1% by mass and B ₂ O ₃ / Na ₂ O (mass ratio) of 1.7 to 4. The manufacturing method of the glass micro hollow body in any one of said (1)-(4) which supplies and foams glass frit whose D50 is 8 micrometers or less in a flame.
(6) The method for producing a glass microhollow according to (5), wherein the glass frit is dispersed in 1 to 8 m ³ of air per kg of the glass frit, mixed with the combustion gas, and supplied into the flame.
(7) The manufacturing method of the glass micro hollow body as described in said (5) or (6) whose D90 of glass frit is 15 micrometers or less and D50 is 2-7 micrometers.

  The glass micro hollow body of the present invention has a specific fine particle size and particle size distribution, and also has a specific particle density, so that there is no difference from the specific gravity of the added polymer material. Sometimes, the dispersion in the polymer material is smoothly and uniformly dispersed. As a result, the resulting polymer material containing the glass microhollow body has uniform physical properties. Moreover, since it has a specific fine particle size and particle size distribution, a material that can be added to a raw material component of a fine polymer material and has improved surface smoothness can be obtained. In addition, since the glass micro hollow body of the present invention has a specific composition, it has excellent water resistance and low alkali elution, so that when added to a polymer material such as a resin, the resin foams or is molded. The fluidity of is not disturbed. Furthermore, according to this invention, the manufacturing method with a sufficient yield of such a glass micro hollow body is also provided.

The glass micro hollow body of the present invention has a glass composition of SiO ₂ : 60 to 80% by mass, Na ₂ O: _{2 to} 12.5% by mass, CaO: 5 to 15% by mass B ₂ O ₃ : 4 to 15 mass%, and _SO 3: 0.05 to 1 comprises mass%, and _{B 2 O 3 / Na 2 O} ( weight ratio) having 1.2 to 3.5. By having such a composition, the above-described characteristics can be reached, and since the hygroscopic property is small, the water resistance is large, and a micro hollow body having a small alkali elution degree is obtained. Further, even when a minute hollow body is mixed in a resin or the like, it is possible to suppress the foaming of the resin or the deterioration of the moldability and the like due to the decrease in fluidity during molding.

Among them, glass microballoons of the present invention, the composition of the _glass, SiO 2: 65 to 75 _wt%, Na 2 O: _3~6 wt%, CaO: 8 to 13 _wt%, B _{2 O} 3: 6 8.5 wt%, and _SO 3: 0.05 to 1 comprises mass%, and _{B 2 O 3 / Na 2 O} ( weight ratio) preferably has a composition which is 1.35 to 3. The total alkali metal oxide is 2 to 12.5% by mass, preferably 4 to 8% by mass, and the total alkaline earth metal oxide is 5 to 15% by mass, preferably 8 to 15% by mass. Preferably there is.

Moreover, the glass which forms a glass micro hollow body can contain the following other components, Thereby, the characteristic of a glass micro hollow body can be improved. K ₂ O: 0 to 3% by weight, preferably from 0.5 to 1.5 _wt%, Li 2 O: 0 to 3% by weight, preferably from 0.5 to 1.2 wt%, MgO: 0 to 3 mass %, preferably 0 to 1.5 wt%, ZnO: 0 to 3% by weight, preferably from 1.0 to 2.5 _{wt%, Al} 2 O 3: _0~3 wt%, preferably 0.5 to 1 .5 _{wt%, P} 2 O 5: _0~3 wt%, preferably from 1.1 to 2.0 _{wt%, Sb} 2 O 3: _{0~1 wt%, As} 2 O 3: _0~1 wt%.

  The particle size distribution of the glass microhollow body has a great influence on the particle density, pressure strength, and physical properties of the additive material of the glass microhollow body. In the present invention, the glass micro-hollow body needs to have a passing cumulative ratio D90 of 30 μm or less in the particle size distribution by laser scattering particle size measurement or JIS standard sieve. When this D90 exceeds 30 μm, when added to a fine polymer material such as a thin film paint, characteristics such as surface smoothness are deteriorated. D90 is preferably 20 μm or less, and particularly preferably 17 μm or less. Further, in the present invention, it is necessary that the accumulated cumulative ratio D50 (also referred to as an average particle diameter) in the particle size distribution by laser scattering particle size measurement of the glass microhollow body is within a predetermined range, and D50 is 10 μm or less, preferably 8 μm or less is suitable.

The particle density of the glass microballoons of the present invention is required to be 0.8~1.2g / cm ^3, and the particle density is greater than 1.2 g / cm ^3, glass microballoons polymeric material If it is less than 0.8 g / cm ³ , the glass micro-hollow body will float in the polymer material, making it difficult to disperse smoothly and uniformly. In this case, the particles of the glass micro-hollow body are unevenly present. This seems to be due to the influence of gravity due to the large difference between the density of the glass micro hollow body and the polymer material. As a result, the physical properties of the resulting polymer material become non-uniform and desired characteristics cannot be obtained. In particular, the particle density of the glass microhollow body is preferably 0.9 to 1.1 g / cm ³ .

  Moreover, the glass micro hollow body of the present invention has a low alkali elution degree, preferably 0.08 meq / g or less, particularly 0.06 meq / g or less. Thereby, the water absorption of the glass micro hollow body is improved, and when added to the resin, the resin does not foam or the fluidity during molding is not hindered.

Although the manufacturing method of the glass micro hollow body of this invention is not limited, Preferably, it manufactures as follows. That is, in the present _invention, SiO 2: 58 to 75 _wt%, Na 2 O: from 3 to 12.5 wt%, CaO: 5 to 15 _{wt%, B} 2 O 3: _8~15 wt% and _SO 3: 0 It is manufactured by using a glass frit having a composition containing 0.05 to 1% by mass and B ₂ O ₃ / Na ₂ O being 1.7 to 4. The glass frit having such a composition has an appropriate foaming rate when producing a glass microhollow body, and is effective for reducing the particle density and alkali elution of the obtained glass microhollow body.

The glass frit, among _others, SiO 2: 58 to 70 _wt%, Na 2 O: 3 to 8 wt%, CaO: 7 to 12 _{wt%, B} 2 O 3: _11~15 wt%, and _SO 3: It is preferable to have a composition containing 0.05 to 1% by mass and having B ₂ O ₃ / Na ₂ O of 1.35 to ₃ . Further, the total alkali metal oxide is 3 to 15% by mass, preferably 3 to 10% by mass, and the total alkaline earth metal oxide is 5 to 15% by mass, preferably 7 to 12% by mass. Is preferred.

In addition, the glass frit can contain other components such as the following, thereby controlling the characteristics of the glass microhollow body to be produced. K ₂ O: 0 to 3% by weight, preferably from 0.5 to 1.5 _wt%, Li 2 O: 0 to 3% by weight, preferably from 0.5 to 1.2 wt%, MgO: 0 to 3 mass %, preferably 0 to 1.5 wt%, ZnO: 0 to 3% by weight, preferably from 1.0 to 2.5 _{wt%, Al} 2 O 3: _0~3 wt%, preferably 0.5 to 1 .5 _{wt%, P} 2 O 5: _0~3 wt%, preferably from 1.2 to 2.0 _{wt%, Sb} 2 O 3: _{0~1 wt%, As} 2 O 3: _0~1 wt%.

  The particle size distribution of the glass frit is important because it affects the properties of the obtained glass microhollow body, including the particle size distribution. The particle size of the glass frit is preferably D90 of 20 μm or less, particularly preferably 15 μm or less. When D90 is larger than 20 μm, it is not possible to obtain an excellent desired particle size distribution of the glass microhollow body obtained after foaming. Further, the average particle diameter D50 of the raw glass frit also affects the particle density after foaming, and D50 is preferably 8 μm or less, particularly 2 to 7 μm.

As a means for producing the glass micro hollow body by foaming the glass frit, the following means is preferably employed. First, the glass frit is dispersed in 1 to 8 m ³ of air per 1 kg of the glass frit. Next, the air containing the glass frit dispersed therein is mixed with a combustion gas such as LPG (the volume ratio of air to the mixed gas of combustion gas and air is preferably 7 to 21), and the mixture is mixed at 1000 to 1200 ° C. It is performed by supplying into a flame and allowing it to pass through the flame for 0.1 to 5 seconds. In this case, the ratio of the air used for dispersion of the glass frit is particularly preferably 2 to 7 m ³ per kg of the glass frit. In this case, a glass micro hollow body can be obtained when the foaming ratio of the glass frit is 70% or more, particularly 75% or more, and the glass micro hollow body has a high yield without performing a sieving operation. Obtained stably. Of course, if necessary, classification with a sieve may be performed to further adjust the particle size distribution. In addition, the said foaming rate means the percentage of the weight of the glass micro hollow body which is a water floating product with respect to the weight of all the products containing the non-foamed product obtained from the foaming process of a glass frit.

EXAMPLES Next, although an Example is given and this invention is demonstrated further more concretely, this is an illustration and does not restrict | limit the interpretation of this invention. In the following, analysis of glass composition, alkali elution degree, particle size distribution of glass micro-hollow body, particle density, and volume fracture rate were obtained as follows.
・ Analysis of glass composition:
Each component was quantitatively analyzed by fluorescent X-ray analysis or ICP emission analysis.
・ Alkali elution:
The water floating product (bubble) of the glass micro hollow body was measured according to ANS / ASTN D3100-78.
・ Particle size distribution of glass micro hollow body:
It measured by the method by sieving with a laser scattering type particle size measuring device or a JIS standard sieve.
-Particle density of glass hollow body:
It was measured by a gas displacement measurement method.
・ Volume fracture ratio of glass micro hollow body:
A hydrostatic pressure was applied, and the volume change rate of the sample density before and after loading the pressure was determined and calculated according to the following formula.
Volume fracture rate = (density after pressure load−density before pressure load) × 100
/ Density after pressure loading

Examples 1 and 2
The following raw materials were mixed, put in a crucible, and melted at a furnace temperature of 1300 ° C. for 4 hours. Next, the melted product was put into a water bath and rapidly cooled to obtain 8000 g of a granulated glass frit.
Silicon dioxide: 5281 g, Lime: 1263 g, Borax (pentahydrate): 2591 g, Aluminum oxide: 32 g, Dibasic calcium phosphate: 436 g, Lithium carbonate: 145 g, Potassium carbonate: 123 g, Zinc oxide: 85 g, Bow nitrate: 38 g

The water of the granulated glass frit was drained and dried for 2 hours in a drier maintained at 150 ° C. After drying, 8 kg of this glass frit was put in a dry ball mill together with 40 kg of alumina ball mill, and pulverized so as to have a particle size distribution (D90, D50) shown in Table 1. The ground glass frit is referred to as a raw material powder in the present invention. The raw material powder had the following composition (unit: mass%).
_{SiO 2: 62.5 Na 2 O:} 6.8 LiO 2: 0.7
K ₂ O: 1.0 CaO: 10.1 ZnO: 1.0
B ₂ O ₃ : 14.9 Al ₂ O ₃ : 0.6 P ₂ O ₅ : 2.1
SO ₃ : 0.2
B ₂ O ₃ / Na ₂ O: 2.19 (mass ratio)

The raw material powder is dispersed in air at 80 liters / minute at an input rate of 25 g / minute, and further foamed continuously with 420 liters / minute of a mixed gas of air and LPG (air / LPG volume ratio: 21). The product was supplied to the furnace, immediately cooled, and immediately collected by a bag filter. Table 1 shows the results of measuring the particle size distribution, the particle density, and the volume fracture rate of the collected glass hollow bodies without performing classification operation. Moreover, this glass micro hollow body had the following composition (unit; mass%), and the alkali elution degree was 0.07 meq / g.
_{SiO 2: 72.1 Na 2 O:} 4.1 LiO 2: 0.5
K ₂ O: 0.8 CaO: 10.9 ZnO: 1.0
B ₂ O ₃ : 8.4 Al ₂ O ₃ : 0.6 P ₂ O ₅ : 1.5
SO ₃ : 0.1
B ₂ O ₃ / Na ₂ O: 2.0 (mass ratio)

Examples 3 and 4
In the same manner as in Example 1, a raw material powder was produced using the following raw material formulation, and a glass microhollow was produced in the same manner as in Example 1 using the raw material powder.
SiO ₂ : 60.8 Na ₂ O: 7.7 LiO ₂ : 0.7
K ₂ O: 1.0 CaO: 10.1 ZnO: 1.0
B ₂ O ₃ : 14.7 Al ₂ O ₃ : 0.6 P ₂ O ₅ : 2.1
SO ₃ : 0.6
B ₂ O ₃ / Na ₂ O: 1.91 (mass ratio)

The produced glass microhollow body had the following composition, and the alkali elution degree was 0.07 meq / g.
SiO ₂ : 72.1 Na ₂ O: 4.5 LiO ₂ : 0.5
K ₂ O: 0.8 CaO: 11.1 ZnO: 1.0
_{B 2 O 3: 8.3 Al 2} O 3: 0.6 P 2 O 5: 1.4
SO ₃ : 0.2
B ₂ O ₃ / Na ₂ O: 1.84 (mass ratio)
Table 1 shows the physical properties of the raw material powder and the glass micro hollow body produced.

Comparative Examples 1 and 2
Although it implemented like Example 1, the raw material powder which has the particle size distribution of Table 1 was manufactured by changing grinding | pulverization conditions. Using this raw material powder, a glass microhollow was produced in the same manner as in Example 1. Table 1 shows the physical properties of the manufactured glass microhollows.

Comparative Example 3
Although it implemented like Example 3, the raw material powder which has a particle size distribution of Table 1 was manufactured by changing grinding | pulverization conditions. Using this raw material powder, a glass microhollow was produced in the same manner as in Example 1. Table 1 shows the physical properties of the manufactured glass microhollows.

  Since the glass micro hollow body according to the present invention has the above-mentioned excellent properties, for example, SMC for vehicle exterior plates, cast products, cast molded products, resin molded products such as thin plate molded products, thin film paints, heat insulating paints, etc. When added to various polymer materials such as various paints, it has extremely uniform physical properties, and a smooth resin molded product surface and painted surface can be obtained, and the desired weight reduction effect or heat insulation effect can be obtained. can get. It can also be used for applications where thickness, smoothness, etc. are regulated as a composite material such as a low dielectric constant filler.

  The use of the glass micro-hollow body of the present invention is not limited to the above-mentioned use, but light weight fillers such as cement, mortar, synthetic wood, low melting point metals and alloys such as aluminum and magnesium, and heat insulating and light weight fillers for building materials. It can also be used in various fields and applications such as explosive sensitizing fillers, electrical insulating layer fillers, soundproofing fillers, cosmetic fillers, filter media, blast media and spacers. In addition, if mixed with a large glass hollow body having an average particle diameter of about 90 to 110 μm, the glass microhollow body of the present invention can fill the gaps between large particles, resulting in higher weight reduction, heat insulation effect, A low dielectric constant effect can be obtained.

Claims (7)

SiO _2: 60-80 _wt%, Na 2 O: _2~12.5 wt%, CaO: 5 to 15 _{wt%, B} 2 O 3: _4~15 wt% and _SO 3: 0.05 to 1 wt% And B ₂ O ₃ /
Particles having a glass composition with Na ₂ O (mass ratio) of 1.2 to 3.5, D90 of 30 μm or less, D50 of 10 μm or less, and particle size distribution in particle size distribution by laser scattering particle size measurement A glass micro hollow body having a density of 0.8 to 1.2 g / cm ³ or less.   The glass micro hollow body according to claim 1, wherein the alkali elution degree is 0.08 meq / g or less. The glass micro hollow body according to claim 1 or 2, wherein the D90 is 20 µm or less, the D50 is 2 to 7 µm, and the particle density is 0.9 to 1.1 g / cm ³ .   The glass micro hollow body according to claim 1, wherein the glass micro hollow body is used as a filler of a polymer material. SiO _2: 58 to 75 _wt%, Na 2 O: _3~12.5 wt%, CaO: 5 to 15 _{wt%, B} 2 O 3: _8~15 wt% and _SO 3: 0.05 to 1 wt% includes, and _{B 2 O 3 / Na 2 O} ( mass ratio) has a composition which is 1.7 to 4, in the particle size distribution by a laser scattering type particle size measuring, D90 is at 20μm or less, and D50 of 8μm The manufacturing method of the glass micro hollow body in any one of Claims 1-4 which supplies the glass frit which is the following in a flame, and makes it foam. The method for producing a glass microhollow according to claim 5, wherein the glass frit is dispersed in 1 to 8 m ³ of air per kg of the glass frit, mixed with the combustion gas, and supplied into the flame.   The method for producing a glass microhollow body according to claim 5 or 6, wherein the glass frit has a D90 of 15 µm or less and a D50 of 2 to 7 µm.