JPH08295577A - Multilayered inorganic expanded body and its production - Google Patents

Abstract

PURPOSE: To obtain a stable multilayered inorg. expanded body having a smooth surface and uniform in thickness. CONSTITUTION: A decorative layer is laminated on a substrate layer of porous inorg. lightweight aggregate coated with inorg. expandable powder of <=150μm particle size obtd. by mixing and pulverizing starting material contg. a silica- contg. substance and a blowing agent.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a multilayer inorganic foam and a method for producing the same. More specifically, the present invention relates to a lightweight, multi-layered inorganic foam having excellent heat insulation, nonflammability, and cosmetic properties, and a method for producing the same.

[0002]

2. Description of the Related Art Inorganic foams are lightweight, have a heat insulating property,
It is used as a building material because it has excellent noncombustibility, but its surface is porous and fragile, so it was easy to peel off and stains were likely to adhere. Therefore, as a conventional inorganic foam, a porous inorganic aggregate is mixed with a vitreous sintering agent and a foaming agent for foaming the sintering agent, and the surface material is formed on the base material layer adhered thereto. It is proposed that the layers are laminated and fired and integrated (see Japanese Patent Laid-Open No. 3-279278).

[0003]

However, the vitreous sintering agent mixed with the porous inorganic aggregate is a granular material having a particle size smaller than that of the aggregate, and even if the particles are small, the vitreous material is vitreous. Since it is heavy, the vitreous sintering agent is separated from the aggregate when it is dropped from the hopper and deposited to form the base material layer, or in the inorganic foaming raw material, the vitreous material Since the sinter is unevenly distributed and the vitreous sinter is locally present, that part is quickly melted, a lot of bubbles are taken in, an over-foamed state is formed, strength is low, and dispersion and brittleness occur. Further, even if the glassy sintering agent is made into powder and mixed with the inorganic foaming raw material and adhered to the base material, it is easy to separate in the same manner as described above. Therefore, a part that foams and a part that does not foam are formed in the base material layer, and the base material layer becomes non-uniform, and the decorative layer laminated on the base material layer becomes non-uniform. After that, the inorganic foam has a problem that a portion having weak strength is locally formed, cracks are likely to occur, and the thickness is difficult to stabilize.

In view of the above circumstances, it is an object of the present invention to provide a multilayer inorganic foam having a smooth surface and a uniform thickness and stability.

[0005]

The multi-layered inorganic foam of the present invention has a particle size of 150 μ, which is obtained by mixing and pulverizing a powder containing a silicic acid-containing substance and a foaming agent with a porous inorganic lightweight aggregate.
It is characterized by comprising a base material layer formed by coating an inorganic expandable powder of m or less, and a decorative layer laminated on the base material layer.

Further, a base material layer formed by mixing a porous inorganic lightweight aggregate and an inorganic expandable powder having a particle size of 150 μm or less, which is obtained by mixing and pulverizing a powder containing a silicic acid-containing substance and a foaming agent, It is characterized by comprising a decorative layer laminated on the base material layer.

The method for producing a multilayer inorganic foam of the present invention comprises coating a porous inorganic lightweight aggregate with an inorganic expandable powder having a particle size of 150 μm or less, which is obtained by mixing and pulverizing a powder containing a silicic acid-containing substance and a foaming agent. It is characterized in that a decorative layer is laminated on the base material layer made of the above, and the obtained laminated body is heated to be melted and integrated.

[0008] In addition, a makeup is formed on a base material layer obtained by mixing a porous inorganic lightweight aggregate and an inorganic expandable powder having a particle size of 150 μm or less, which is obtained by mixing and pulverizing a powder containing a silicic acid-containing substance and a foaming agent. It is characterized in that the layers are laminated, and the obtained laminated body is heated for solution integration.

[0009]

According to the method for producing a multilayer inorganic foam of the present invention, a raw material containing a silicic acid-containing substance and a foaming agent is mixed and pulverized in advance so as to foam at a firing temperature, and an inorganic foamable powder is a lightweight aggregate. In order to form the base material layer, the components of the inorganic foamable raw material are not separated when the base material layer is formed, so that a uniform base material layer can be deposited. As a result, a multilayer inorganic foam having a dense surface and a uniform thickness can be obtained.

[0010]

EXAMPLES The multilayer inorganic foam of the present invention and the method for producing the same will be described below.

The multi-layer inorganic foam of the present invention is obtained by coating a lightweight inorganic porous aggregate with an inorganic foaming powder having a particle size of 150 μm or less, which is obtained by mixing and pulverizing a powder containing a silicic acid-containing substance and a foaming agent. And a decorative layer laminated on the base material layer.

Alternatively, it is prepared by mixing and crushing a porous inorganic lightweight aggregate and a powder containing a silicic acid-containing substance and a foaming agent.
The base layer is formed by mixing an inorganic foamable powder having a particle size of 150 μm or less, and a decorative layer laminated on the base layer.

Examples of the above-mentioned porous inorganic lightweight aggregate include perlite particles obtained by rapidly expanding pearlite, fuyolite particles obtained by rapidly expanding obsidian, and shirasu balloon obtained by rapidly expanding shirasu. However, since these have low grain strength, it is preferable to use soda lime glass as a main component, to which a plasticizer, a foaming agent, and the like are added, and a glass foam that has been foamed in advance is crushed. It is preferable to use mass-produced soda-lime glass such as plate glass and bottle glass, particularly, one that effectively uses waste from the viewpoint of effective use of resources.

[0014] The above-mentioned lightweight aggregate aims to reduce the weight and improve the heat insulating property, and also prevents unevenness from being formed on the surface of the laminated decorative layer due to excessive gas release during firing, resulting in a smooth finished surface and a stable surface. It is used to obtain thickness. And the particle size of the lightweight aggregate is usually 0.1-8 m
Although it is about m, the inorganic expandable powder fills the gaps between the particles of the lightweight aggregate, and is melt-foamed by firing to stably bond the particles, prevent water absorption, and have stable strength. Therefore, it is preferable that the thickness is about 0.5 to 3 mm.

Specific examples of the silicic acid-containing substance which is the main component in the inorganic foaming raw material include naturally occurring igneous rocks, silicate soil such as volcanic ash, and soda lime glass. As the foaming agent, bentonite, dolomite, silicon carbide, magnesium carbonate, calcium carbonate or the like can be used. In addition to the foaming agent, a plasticizer and a flux for adjusting the firing temperature may be mixed with the inorganic foamable powder. The particle size or particle size of the inorganic expandable powder is 150 μm or less in order to obtain uniform foaming. And, it is preferably 50 μm or less.

In order to obtain a dense foam, it is preferable to use the soda-lime glass as a main component rather than adding a flux and a foaming agent to igneous rocks, volcanic ash and the like. The main reason for using soda lime glass is that when a mesh belt kiln with a heat resistant stainless steel mesh belt is used as a firing furnace, the heat resistance temperature of the stainless steel mesh belt is about 1000 ° C. Is unnecessary, and since it is a raw material that has been calcined once, the elution of the water-soluble component is extremely small, so that a stable and high-strength foam layer can be obtained. Further, a glass material having high strength, such as G light (trade name, Sunlight Co., Ltd.)
The main component of inorganic expandable powder (soda lime glass 4
When soda lime glass (0% or more) is used, the softening point (melting point) is equal to or less than that of the glass material and the coefficient of thermal expansion is about the same. A multilayer inorganic foam can be obtained.

As the plasticizer, viscosity, bentonite, etc. can be used. As the flux, generally inexpensive soda ash, sodium nitrate, etc. can be used. Since the amount of such flux used is a water-soluble substance, it elutes with the water added to the lightweight aggregate, resulting in inhomogeneous foaming, so it is necessary to keep it as small as possible, preferably 5% (weight %, The same as below).

The raw material of the base material layer is, for example, 0.1 to 8 mm.
After adding water to the lightweight aggregate, or adding a binder in which a binder (for example, PVA, water glass, etc.) is dissolved in an aqueous solution, and mixing with a mixer to moisten the lightweight aggregate, It can be obtained by mixing it with an inorganic foaming material and coating it on the surface of a lightweight aggregate. It should be noted that a mixed material may be used instead of the coating. Further, the composition ratio of the base material layer is 0.05 to 3 parts by weight, preferably 0.1 to 1.
5 parts by weight. The reason is that if it is less than 0.05 parts by weight, the bonding strength between the lightweight aggregates is weak, and if it exceeds 3 parts by weight, the foamable raw material and the lightweight aggregate are separated from each other, and a stable product can be obtained. Because it will be difficult.

The decorative layer is a glassy layer containing an inorganic coloring pigment or the like. As the raw material, powders such as glass and frit, granulated materials and crushed particles are used.
In order to obtain a stable decorative layer that is uniformly laminated, granules are preferable. The material of the decorative layer is not limited to foaming or non-foaming, and can be appropriately selected depending on the application and design.

As a method for producing the multi-layered inorganic foam of the present invention, the base layer previously prepared on the mesh belt of the mesh belt kiln and the raw materials for the decorative layer are sequentially laminated from the respective hoppers to obtain A method in which the laminated body is conveyed to a firing furnace by a mesh belt and fired and integrated can be given. With this method, the maximum firing temperature is 100
Continuous production at about 0 ° C., preferably 900 ° C. or less is preferable from the heat resistance of the firing furnace.

In order to obtain a multi-layered inorganic foam which is stable in quality depending on the firing temperature conditions of the above-mentioned production method, it is preferable to use soda lime glass containing 40% or more of the lightweight aggregate and the inorganic expandable powder as the main components. preferable. The reason is that if it is less than 40%, a large amount of the flux is required, the flux is likely to be separated, and the foaming becomes unstable, resulting in a large variation in strength and an unstable thickness, and smoothness of the surface. This is because it is hard to get them.

In the multi-layered inorganic foam of the present invention, an intermediate layer made of, for example, inorganic particles can be interposed between the base layer and the decorative layer.

As the inorganic granular material of the intermediate layer, glass particles, broken particles of the fired product, and the like can be used.

The intermediate layer fills the surface recesses of the base material layer to make it smooth, or serves as a stress relaxation layer when the difference in thermal expansion between the base material layer and the decorative layer is large, so that a more stable multilayer inorganic foam can be obtained. You can Therefore, the intermediate layer has a thermal expansion coefficient equal to or lower than that of the base material layer, does not generate tensile force in the decorative layer, and makes the decorative layer less prone to cracks, and thus shrinks less like a granular substance. Those that absorb the irregularities of the base material layer are preferable. Therefore, the coefficient of thermal expansion of the intermediate layer is preferably a coefficient of thermal expansion that is located between or at the same level as the base material layer and the decorative layer.

Next, the multilayer inorganic foam of the present invention will be explained based on examples, but the present invention is not limited to such examples as a matter of course.

Example 1 Preparation of Inorganic Effervescent Powder 80% bottle glass powder, 5% bentonite, 1 sodium nitrate
%, Soda ash 5%, clay 9%
g was put into a pot mill together with a 10 mmφ steel ball, and mixed and ground for 10 hours to obtain an inorganic foamable powder having an average particle size of 10 μm.

Preparation of raw material for base material layer 8% of 4% PVA liquid was sprayed on a glass foam aggregate (G-light (trade name) of Sunlite Co., Ltd.) having a particle size of 0.5 to 3 mm, and then it was added to an Erich mixer. After being charged and uniformly moistened, 30% of the inorganic expandable powder was added to the aggregate to obtain coated particles.

Adjustment plate glass powder as a raw material for decorative layer 94%, borax 1%, bentonite 5% and M66 (trade name, pink pigment manufactured by Nisto Sangyo Co., Ltd.) 3%
50 kg of compounded raw material (external) was manufactured, and this was put into a pot mill together with a 10 mmφ steel ball, and mixed and pulverized for 10 hours. The obtained cosmetic powder was granulated with a pan-type granulator to obtain granules having a particle size of 1 to 2.5 mm.

Firing The above-prepared raw materials for the base layer and the decorative layer were used to prepare a laminate, which was fired and solution-integrated to obtain a multilayer inorganic foam.

For the firing, a firing furnace of a tunnel kiln having a total length of 39 m, in which a heat-resistant mesh belt was installed for transportation, was used. Alumina was applied as a mold release material on a mesh belt with a width of 1 m, and the base layer raw material was uniformly charged to have a thickness of 15 mm, and the decorative layer raw material was laminated to have a thickness of 4 mm. did. The obtained laminated body was conveyed to the pre-tropical zone, and then passed through the firing zone, the quenching zone, the slow cooling zone, and the cooling zone in that order, and then discharged from the furnace outlet.

The firing temperature was 850 ° C. The moving speed of the mesh belt was 25 cm / min, and the time required to put in and out of the furnace was 160 minutes.

Example 2 The same as Example 1 except that an intermediate layer was laminated between the base material layer and the decorative layer in Example 1 above.

As the material for the intermediate layer, crushed bottle glass was used to prepare crushed particles having a particle size of 0.5 to 1.5 mm.
Next, a base material layer, an intermediate layer, and a decorative layer were sequentially laminated, and this was baked and integrated to obtain a multilayer inorganic foam.

The appearance of the multi-layered inorganic foams obtained as described above was observed.
It was found to be a multilayer inorganic foam having a dense surface and a uniform thickness. It was also confirmed that the strength was excellent.

[0035]

As described above, in the multilayer inorganic foam of the present invention, since the inorganic expandable powder having a particle size of 150 μm or less obtained by integrally mixing and pulverizing the silicic acid-containing substance and the foaming agent is used, it is homogeneous and lightweight. The substrate layer can be deposited by mixing with the aggregate. As a result, the intermediate layer and the decorative layer are uniformly laminated, and after the firing and integration, the surface can be made dense and the thickness can be made uniform.

Front page continuation (72) Inventor Ryo Nagai 2 Takasago Industrial Co., Ltd. 2321, Tachi-cho, Toki City, Gifu Prefecture (72) Inventor Yoshio Nagao 2 23-1 Tachi-machi, Toki City, Gifu Takasago Industrial Co., Ltd. Within

Claims (12)

[Claims] 1. A base material layer formed by coating a porous inorganic lightweight aggregate with a raw material containing a silicic acid-containing substance and a foaming agent, and coating the same with an inorganic expandable powder having a particle size of 150 μm or less, A multilayer inorganic foam comprising a decorative layer laminated on the base material layer. 2. A base material layer formed by mixing a porous inorganic lightweight aggregate and an inorganic expandable powder having a particle size of 150 μm or less, which is obtained by mixing and pulverizing a raw material containing a silicic acid-containing substance and a foaming agent, A multilayer inorganic foam comprising a decorative layer laminated on the base material layer. 3. The softening point of the inorganic foamable raw material is lower than the softening point of the lightweight aggregate.
The multilayer inorganic foam described. 4. The soda-lime glass as a main component of the lightweight aggregate and the inorganic foaming raw material.
The multilayer inorganic foam described. 5. The multilayer inorganic foam according to claim 1, wherein an intermediate layer is interposed between the base layer and the decorative layer. 6. The multilayer inorganic foam according to claim 5, wherein the coefficient of thermal expansion of the intermediate layer is equal to or lower than the coefficient of thermal expansion of the base material layer. 7. A base material layer comprising a porous inorganic lightweight aggregate mixed with a raw material containing a silicic acid-containing substance and a foaming agent and pulverized with an inorganic expandable powder having a particle size of 150 μm or less. A method for producing a multi-layered inorganic foam, which comprises laminating a decorative layer and heating the obtained laminated body for solution integration. 8. A substrate layer formed by mixing a porous inorganic lightweight aggregate and an inorganic expandable powder having a particle size of 150 μm or less, which is obtained by mixing and pulverizing a raw material containing a silicic acid-containing substance and a foaming agent. A method for producing a multi-layered inorganic foam, which comprises laminating a decorative layer and heating the obtained laminated body for solution integration. 9. The softening point of the inorganic foamable raw material is lower than the softening point of the lightweight aggregate.
The manufacturing method described. 10. The method according to claim 7, 8 or 9, wherein the main components of the lightweight aggregate and the inorganic foaming raw material are soda lime glass. 11. The method according to claim 7, 8, 9 or 10, wherein a decorative layer is laminated on the base material layer with an intermediate layer interposed therebetween, and the obtained laminated body is heated for solution integration. 12. The method according to claim 11, wherein the thermal expansion coefficient of the intermediate layer is equal to or lower than the thermal expansion coefficient of the base material layer.