KR20060068929A - The foamed ceramics shape of high strength and the making method thereof - Google Patents

Abstract

The present invention relates to a ceramic molded body and a method for manufacturing the same, which is used as a building material and has a non-flammability, heat insulation, light weight, sound absorption, antibacterial properties, adhesive properties, and more particularly, in a sodium aluminosilicate solution. To prepare a primary mixture by mixing clay or bentorite to increase the compressive strength in a certain ratio, and mixing and stirring the heat-expanded vermiculite or pearlite and ocher powder in a predetermined ratio to prepare a secondary mixture The present invention relates to a high-strength foamed ceramic molded body and a method for manufacturing the same, wherein the molding mixture is filled with a secondary mixture and heated and foamed in a microwave oven at high temperature.

Sodium aluminosilicate, clay, bentorite, vermiculite, pearlite, microwave

Description

High-strength foamed ceramic molded body and its manufacturing method

The present invention relates to a ceramic molded body and a method for manufacturing the same, which is used as a building material and has a non-flammability, heat insulation, light weight, sound absorption, antibacterial properties, adhesive properties, and more particularly, in a sodium aluminosilicate solution. To prepare a primary mixture by mixing clay or bentorite to increase the compressive strength in a certain ratio, and mixing and stirring the heat-expanded vermiculite or pearlite and ocher powder in a predetermined ratio to prepare a secondary mixture The present invention relates to a high-strength foamed ceramic molded body and a method for manufacturing the same, wherein the molding mixture is filled with a secondary mixture and heated and foamed in a microwave oven at high temperature.

In general, vermiculite is a material produced by the alteration of biotite, has a pearl luster, easily decomposes in acid, has a high cation exchange capacity, and heat-expanded vermiculite is porous and has good absorption ability. It is widely used as a soundproofing material, but has a self-elasticity that expands to about 20 times its original thickness when heated to 900 ℃, and has a molding step such as a heating press step when processing heat-expanded vermiculite as a building material. There was a problem that is not applicable at all in the process.

In addition, pearlite is a non-flammable inorganic material that is expanded by heat-treating pearlite, obsidian, and pine stone at high temperature, and there is no risk of toxic gas in the event of fire. In the process of press molding step, such as the heating press step when processing the material, there was a problem that the adhesive strength, sound absorption of the finished product is lowered by breaking the pores of the pearlite particles.

In the related art, the applicant has previously filed a method of manufacturing a building material having a multifunctional, porous ceramic shape using the pearlite of Patent Application No. 10-2003-0054548 using the pearlite having the above characteristics. As a heat-insulating and sound-absorbing material, a liquid silicate composed of sodium silicate alumina (Na ₂ O · Al ₂ O _3X · SiO ₂ ), which is a binder and a binder, and a curing agent and water are mixed in a proportion. Mixing and kneading in a stirrer and conveying the blending material added excessively to the kneaded pearlite by using a mesh conveyor to filter and put into a molding mold of a certain shape, while pressing the non-woven fabric horizontally in the center of the molding press-type molding machine Pressure molding and demolding, and then gradually warmed to 60 ~ 250 ℃ in a general continuous drying furnace, followed by curing for 1-2 hours and cooling However, the ceramic building material manufactured by the above method has the property of dissolving liquid sodium silicate made of sodium silica aluminate in water, thereby increasing the hardness and strength of the ceramic building material by water or moisture. When it is press-molded by press, the pearlite particles are pressurized and broken to block the pores of the pearlite particles, so that the sound absorbency is lowered, the original particles are destroyed, the strength is lowered, and the broken particles are continuously buried on the surface of the ceramic building material It is inferior in adhesiveness to other materials such as panels, and when it is dried at high temperatures during curing and drying processing, cracks are generated or deformed on the surface. There were problems that cost increased.

The present invention is to solve the problems as described above is low in solubility in water as a binder and a ceramic molded body using a sodium aluminosilicate solution having a foaming property at a high temperature is low solubility in water is low hardness and strength By applying a new high-temperature foam molding method other than the press pressure molding method to prevent the pearlite particles from being cracked as the pearlite particles are pressurized to lower the compressive strength and adhesiveness, even in the case of heat-expanded vermiculite by the high temperature foam molding method The purpose of the present invention is to be able to manufacture a foamed ceramic molded article having high strength and excellent heat insulation, and to be able to manufacture a high strength foamed ceramic molded article having excellent lightness and heat absorbability, such as lightness in a short time without cracking or deformation on the surface.                         

To achieve this purpose, a primary mixture was prepared by mixing clay or bentorite for increasing the compressive strength in a sodium aluminosilicate solution having low solubility in water as a binder and foaming at a high temperature. The secondary mixture is prepared by mixing and stirring the expanded and expanded vermiculite or pearlite and ocher powder in a predetermined ratio, respectively, and then filling the secondary mixture in a molding mold and heating and foaming in a high temperature microwave furnace. The present invention relates to a high-strength foamed ceramic molded body and a method of manufacturing the same.

Hereinafter, the configuration of the present invention in detail.

High-strength foamed ceramic molded body according to the present invention is a completely nonflammable material, while maintaining high heat insulation, adhesiveness, light weight, and water resistance, which is enhanced in compressive strength, sound absorption, antibacterial and deodorizing effect, etc. Used.

First, in the step of preparing a mixture for producing a ceramic molded body according to the present invention, a sodium aluminosilicate solution (Na ₂ O Al ₂ O ₃ ·) having low solubility in water as a binder and foamability at high temperatures SiO ₂ · xH ₂ O) To prepare a primary mixture by mixing 5 to 25 parts by weight of clay or bentorite for increasing the compressive strength and adhesion to 100 parts by weight of the inorganic mixture with respect to 100 parts by weight of the inorganic material The secondary mixture is prepared by mixing 45 to 90 parts by weight of heat-expanded vermiculite or pearlite, which is made of porous and is light and has excellent sound absorption and thermal insulation.

The sodium aluminosilicate solution acts as a binder to 30% by weight of sodium oxide (Na ₂ O), 7.5% by weight of silicon dioxide (SiO ₂ ) and 0.3 to 5% by weight of aluminum oxide (Al ₂ O ₃ ). And water (H ₂ O) is used in the ratio of 57.5 ~ 62.2% by weight, the sodium aluminosilicate solution formulated at the specific ratio is low solubility in water, no whitening phenomenon, compressive strength and adhesion This large foam is characterized in that it foams within about 30 minutes at 300 ° C and foams within about 1 minute at 800 ° C.

The clay or bentorite is generally added in a predetermined ratio to increase the compressive strength and adhesiveness of the finished product as a material having excellent thermal insulation and adhesiveness, and the particle size of the clay or bentorite is 1 ~ 10μm using It is preferable.

Since the primary mixture of sodium aluminosilicate and clay or bentorite is slowly solidified in a mixed state, it is preferable to mix heat-expanded vermiculite or pearlite within 10 minutes after mixing.

The heat-expanded vermiculite or pearlite which is added to the primary mixture and mixed is light, porous, non-flammable, heat-insulating and sound-absorbing, and the heat-expanded vermiculite is preferably used with a particle size of about 0.8 to 10 mm. It is preferable to use a particle having a size of about 0.5 to 10 mm.

In addition, if necessary, 5 to 10 parts by weight of ocher powder may be mixed to impart functionality to the secondary mixture to 100 parts by weight of the primary mixture, and the ocher powder is generally excellent in antibacterial and deodorizing effects. And it is preferable to use the one having a particle size of about 1 ~ 10μm to be added to exhibit the functions such as constant humidity control, far infrared radiation and the like.

When mixing the expanded expanded vermiculite or pearlite and ocher powder in the primary mixture is preferably stirred for about 2 to 5 minutes evenly mixed, if stirred for a long time mixing the ceramic mixture to block the pores of vermiculite or pearlite Heat insulation, sound absorption, and the like are lowered.

Next, in the step of foam molding the secondary mixture, the secondary mixture is filled into a molding mold having a predetermined shape, but filled to about 1/2 to 2/3 and heated to 300 to 800 ° C. It is placed in a microwave furnace and heated for 1 to 30 minutes to foam.

The molding mold is made of a non-conductive material such as ceramic, and is not affected by microwaves generated in a conventional microwave furnace.

If necessary, in the process of filling the molding mixture with a secondary mixture, a honeycomb-like thin support such as paper fiber, nonwoven fabric or polyester may be inserted in a horizontal state to increase the strength of the finished ceramic molded body.

The microwave furnace is a conventional heating device that generates microwaves of ultrahigh frequency (UHF) of 300 to 3,000 MHz and microwaves of super high frequency (cmF) of 3 to 300 GHz, which are higher in frequency than microwaves. Due to the nature of microwaves, the secondary mixture is heated from the inside to be heated and dried evenly in a short time without cracking or deformation even at a high temperature. In the present invention, a microwave furnace manufactured by Jinyang Platech Co., Ltd. .

The heating temperature is specified according to the characteristics of sodium aluminosilicate (foaming sodium aluminosilicate) to be foamed when heated at 300 ℃ or more, the heating time can be adjusted according to the thickness and size of the molded body.

The heated secondary mixture at constant temperature and time conditions is not foamed indefinitely, but proportional to the amount of sodium aluminosilicate added, and is generally about 1.5 to 2 times the volume of the secondary mixture put into the molding mold. The ceramic molded body is completed.

Embodiments according to the present invention are as follows.

<Example 1>

Sodium aluminosilicate (sodium aluminosilicate) (30% by weight of sodium oxide (Na ₂ O), 7.5% by weight of silicon dioxide (SiO ₂ ), ₂ % by weight of aluminum oxide (Al ₂ O ₃ ), water (H ₂ O) 60.5 weight 10 g of clay is mixed with 100 g of a solution, and 100 g of the first mixture is taken and 60 g of heat-expanded vermiculite are mixed to prepare a second mixture. The secondary mixture prepared at the above ratio is filled into a ceramic molding mold having a width of 100 mm, a length of 100 mm, and a height of 50 mm, but only filled up to about two thirds of the height, and then microwaved with a microwave by Jinyang Platec Co., Ltd. ) And foamed at 500 ° C. for 20 minutes to produce a ceramic molded body having a width of 100 mm, a length of 100 mm, and a height of 50 mm.

<Example 2>

Sodium aluminosilicate (sodium oxide (Na ₂ O) 30% by weight, silicon dioxide (SiO ₂ ) 7.5% by weight, aluminum oxide (Al ₂ O ₃ ) 2% by weight, water (H ₂ O) 60.5 weight 10 g of bentorite was mixed with 100 g of a solution, and 100 g of the first mixture was taken, and 60 g of pearlite was mixed to prepare a second mixture. The secondary mixture prepared at the above ratio is filled into a ceramic molding mold having a width of 100 mm, a length of 100 mm, and a height of 50 mm, but only filled up to about two thirds of the height, and then microwaved with a microwave by Jinyang Platec Co., Ltd. ) And foamed at 500 ° C. for 20 minutes to produce a ceramic molded body having a width of 100 mm, a length of 100 mm, and a height of 50 mm.

<Comparative Example>

A mixture of 430 g of pearlite, 132.5 g of liquid sodium silicate made of sodium silica alumina, 45 g of a hardener (gypsum) and 60 g of water was mixed and kneaded in a stirrer, and the kneaded mixture was kneaded using a mesh conveyor. After transporting and filtering, it is put in a metal molding mold and pressurized with a press molding machine to produce 100mm in width, 100mm in length and 50mm in height. Then, it is demolded and gradually warmed to 60 ~ 250 ℃ in a general continuous drying furnace, and cured for 2 hours after drying. A ceramic molded body is manufactured.

Examples 1 and 2 and Comparative Example prepared as described above were measured for density (light weight), bending strength, compressive strength, heat resistance, thermal conductivity, combustibility, adhesiveness under the same conditions, respectively. Same as

The adhesion measurement is to test the adhesion after 20 hours after the adhesive was applied to the metal panel with a thickness of 1mm and after bonding Examples 1 and 2 and Comparative Example.

<Table 1> Measurement results of Examples 1 and 2 and Comparative Examples

           division                                              Test Items  Example 1  Example 2  Comparative example  Remarks Density (kg / ㎥)                                          289 280 337 Lightweight Bending Strength (N / ㎠)                                          58 56 47 Compressive strength (N / ㎠)                                          93 89 71 Heat resistance (㎡h ℃ / ㎉)                                          0.211 0.189 0.114 Thermal Conductivity (w / mK)                                          0.032 0.034 0.093 Combustibility (sec)                                          0 0 0 Adhesive                                          Good Good Inadequate

As shown in the measurement results of <Table 1>, the ceramic shaped bodies of Examples 1 and 2 according to the present invention have the same size as the ceramic shaped bodies of the comparative example, but have a small density, light weight, high bending strength and high compressive strength, and high thermal resistance. It can be seen that it is possible to provide a foamed ceramic molded body having a large heat conductivity and a small heat resistance and excellent heat resistance and excellent adhesiveness.

As described above, according to the present invention, the ceramic formed body using the sodium aluminosilicate solution having low solubility in water and foaming property at high temperature as a binder has high compressive strength, light weight and excellent water resistance, and is not a press-pressing method. The newly applied high temperature foam molding method prevents the pearlite particles from being cracked and deteriorated in compressive strength and adhesiveness, and in the case of heat-expanded vermiculite, a foam ceramic molded body having high strength and excellent thermal insulation is produced by the high temperature foam molding method. It is possible to produce a high-strength foamed ceramic molded body excellent in lightness, heat insulation, and air intake in a short time without cracks or deformation on the surface.

Claims (5)

In the method of manufacturing a ceramic molded body, by mixing 5 to 25 parts by weight of clay or bentorite for increasing the compressive strength and adhesion to 100 parts by weight of sodium aluminosilicate solution having low solubility in water and foamability at high temperature as a binder After preparing a primary mixture, a secondary mold is prepared by mixing 45 to 90 parts by weight of heat-expanded vermiculite or pearlite, which is porous and lightweight, and has excellent sound absorption and thermal insulation, based on 100 parts by weight of the primary mixture. Filling the secondary mixture in a microwave oven heated to 300 ~ 800 ℃ in a state of manufacturing a high-strength foam ceramic molded body, characterized in that the production by heating and foaming for about 1 to 30 minutes. The method of manufacturing a high-strength foamed ceramic molded body according to claim 1, wherein 5 to 10 parts by weight of ocher powder having a particle size of 1 to 10 µm is added and mixed to the secondary mixture to 100 parts by weight of the primary mixture. The method of claim 1, wherein the sodium aluminosilicate solution comprises 30% by weight of sodium oxide (Na ₂ O), 7.5% by weight of silicon dioxide (SiO ₂ ), 0.3-5% by weight of aluminum oxide (Al ₂ O ₃ ) and water ( H ₂ O) A method for producing a high-strength foamed ceramic molded body characterized in that it is specified at a ratio of 57.5 to 62.2% by weight. 2. The high strength foam ceramic according to claim 1, wherein a thin honeycomb-like support made of paper fiber, nonwoven fabric or polyester is inserted in a horizontal state in the process of filling the molding mold with a secondary mixture. Method for producing a molded article. In the ceramic molded body, the primary mixture by mixing 5 to 25 parts by weight of clay or bentorite for increasing the compressive strength and adhesion to 100 parts by weight of sodium aluminosilicate solution having low solubility in water as a binder and foaming at high temperature To prepare a secondary mixture by mixing 45 to 90 parts by weight of heat-expanded vermiculite or pearlite, which is porous and lightweight, and has excellent sound absorption and thermal insulation, based on 100 parts by weight of the primary mixture. A high-strength foamed ceramic molded body, which is prepared by filling a tea mixture and heating it in a microwave furnace heated to 300 to 800 ° C. for about 1 to 30 minutes.