JP2005298225A - Plastic body for ceramic structure and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plastic body for ceramic structure in which a cost is lowered by simplifying a forming process, environmental load is reduced and the quality of the ceramic structure is made high and an efficiently manufacturing method of the same. <P>SOLUTION: The plastic body for the ceramic structure uses a material containing at least 1 mass% hydraulic alumina powder forming a hydrate by hydration reaction as ceramic raw material powder and is manufactured using a 1st powdery mixture to become a multicomponent ceramic in which aluminum oxide (Al<SB>2</SB>O<SB>3</SB>) is bonded with a ceramic component except aluminum oxide (Al<SB>2</SB>O<SB>3</SB>) after fired or a 2nd powdery mixture to become a ceramic composite in which a ceramic component except aluminum oxide (Al<SB>2</SB>O<SB>3</SB>) is dispersed in aluminum oxide (Al<SB>2</SB>O<SB>3</SB>) after fired in addition of the hydraulic alumina powder and has characteristics of (1) 5-34 mm hardness characteristic and (2) ≥5 cm extrusion characteristic. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a ceramic structure clay and a method for producing the same. More specifically, when used for the production of a ceramic structure (ceramic molded body before firing), it has excellent hardness characteristics and extrusion characteristics (high plasticity), so there is no special use of additives such as organic molding aids. In addition, it is possible to impart a desired shape to the ceramic molded body, which can reduce the cost by simplifying the molding process, and release of harmful gases during the heating process of the ceramic molded body, or complete thermal decomposition. Cement clay for ceramics structure and its efficiency, which can prevent residual carbon in organic ceramics from remaining in the ceramic structure, reduce environmental load and improve the quality of the resulting ceramic structure Relates to a typical manufacturing method.

A ceramic structure composed of a ceramic component containing aluminum oxide (Al ₂ O ₃ ) is excellent in characteristics such as heat resistance, corrosion resistance, thermal shock resistance, and mechanical strength, and therefore requires these characteristics. Widely used in structural parts, electronic parts, etc.

Such a ceramic structure, for example, made of aluminum oxide (Al ₂ O ₃₎ and aluminum oxide (Al ₂ O ₃₎ other than the multi-component system ceramics and ceramic component is bonded, after being fired, oxide ceramic component other than aluminum oxide (Al ₂ O ₃₎ to aluminum (Al ₂ O ₃₎ can be mentioned those composed of ceramic composite dispersed. Specifically, examples of multicomponent ceramics include mullite (3Al ₂ O ₃ .2SiO ₂ ), cordierite (2MgO.2Al ₂ O ₃ .5SiO ₂ ), and ceramic composites such as aluminum oxide. , Spinel (MgO.Al ₂ O ₃ ), silicon carbide (SiC) and the like are dispersed.

  However, when producing a ceramic structure (ceramic molded body before firing), it is difficult to prepare a clay for ceramic structure having high plasticity such as clay simply by kneading ceramic raw material powder and water. Thus, it has been difficult to obtain a ceramic structure having a desired shape. Therefore, various researches and developments have been carried out to prepare a highly plastic clay for ceramic structures.

  For example, silica-alumina two-component mineral powders such as mullite and sillimanite are placed in a pressure reaction vessel such as an autoclave and hydrothermally treated in an acidic or neutral solution, thereby converting the mineral surface into kaolinite. A method for developing plasticity is disclosed (see Patent Document 1). Also disclosed is an alumina plastic material obtained by kneading an alumina powder having a plate shape with an organic molding aid and water (see Patent Document 2). Also disclosed is a method of expressing high plasticity by forming an aluminate compound on the surface of α-alumina particles (see Patent Document 3). Moreover, the method of making high plasticity express by making a phosphoric acid compound adhere to the whole surface including the surface or the surface of an alumina particle is disclosed (refer patent document 4). Also disclosed is a method of expressing high plasticity by interposing a void-forming material that is insoluble in water, absorbs water, and deforms itself between primary particles (see Patent Document 5). Further, a method is disclosed in which alumina particles are dispersed in an aqueous solution of aluminum salt and the liquid is neutralized to precipitate alumina hydrate on the surface of the alumina particles to express high plasticity (see Patent Document 6). ). Furthermore, a method for expressing high plasticity by adding agar to alumina or coating the surface of alumina with agar is disclosed (see Patent Document 7).

  However, the technique relating to the ceramic structure clay (a method for producing a ceramic structure) disclosed in the above-mentioned literature has the following problems. That is, when the mineral surface disclosed in Patent Document 1 is made kaolinite to develop plasticity, it requires a high-temperature solution treatment for a long time and a reaction vessel therefor. There was a problem of increasing. In the case of the method for obtaining an alumina plastic material disclosed in Patent Document 2, methyl cellulose, polyvinyl alcohol, carboxymethyl cellulose, polyethylene glycol, and the like are used as organic molding aids. These organic molding aids were molded. When a ceramic structure is produced by firing a clay for ceramic structure (ceramic compact), gas is released by pyrolysis during the firing process, and the released gas may cause bad odors and the environment. There was a problem that would be contaminated. In addition, adding a process to prevent environmental pollution caused by the released gas complicates the process and increases the manufacturing cost. Furthermore, an organic molding aid (organic binder) is added to the fired ceramic structure. If residual carbon or the like remains as residual charcoal or ash, it causes a problem in quality, so that it is necessary to completely remove it by combustion, and there is a problem that the cost for that is excessive and the manufacturing cost is further increased.

  In the case of the method disclosed in Patent Document 3, in order to form an aluminate compound on the particle surface, it is necessary to hydrotreat the raw material containing the alkali metal element at 100 to 300 ° C. and to perform the heat treatment at 250 to 1300 ° C. In addition, these heat treatments have a problem of increasing manufacturing costs.

  In the case of the method disclosed in Patent Document 4, a hydrothermal treatment that satisfies the conditions for adhering phosphate (temperature of 350 ° C. or higher, pressure of 50 atm or higher, time of 5 minutes or longer) is required, There is a problem in that a pressure vessel capable of the treatment is necessary and the manufacturing cost is increased.

In the case of the method disclosed in Patent Document 5, the addition of agar or konjac, which is a polysaccharide that is insoluble in water and absorbs water, is caused by a gas (for example, CO ₂ gas) generated during the firing of the ceramic molded body. There was a problem of causing bad odor and global warming.

  In the case of the method disclosed in Patent Document 6, it requires a neutralization operation of an aluminum salt and requires calcining at a temperature of 300 to 700 ° C., which complicates the operation and increases the manufacturing cost. was there.

In the case of the method disclosed in Patent Document 7, a complicated operation accompanying heating is required for melting agar, increasing the manufacturing cost, and gas generated in the firing process of the ceramic structure kneaded material (for example, CO _2). Gas, etc.) caused a bad odor and global warming.
JP-A-6-157024 JP-A-7-2568 JP-A-8-91830 Japanese Patent Laid-Open No. 9-142836 JP 11-92233 A JP 2000-7327 A JP 2000-1119060 A

  The present invention has been made in view of the above-mentioned problems, and when used in the production of a ceramic structure (ceramic molded body before firing), has excellent hardness characteristics and extrusion characteristics (high plasticity). Without special use of additives such as molding aids, it is possible to impart a desired shape to the ceramic molded body, which can reduce the cost by simplifying the molding process and heat the ceramic molded body. It is possible to prevent the release of harmful gases during the process and the residual carbon residue of organic substances that cannot be thermally decomposed in the ceramic structure, thereby reducing the environmental burden and improving the quality of the resulting ceramic structure. An object of the present invention is to provide a ceramic structure kneaded material and an efficient production method thereof.

  As a result of intensive studies to achieve the above-mentioned object, the present inventors have kneaded ceramic raw material powder containing a predetermined amount of hydraulic alumina powder and water, thereby producing a high-plastic ceramic structure paste. And the present invention has been completed. That is, according to the present invention, the following clay structure clay and a method for producing the same are provided.

[1] A ceramic structure kneaded material, which is produced by kneading ceramic raw material powder and water, and used for producing a ceramic structure,
As the ceramic raw material powder, a powder containing at least 1% by mass of a hydraulic alumina powder that forms a hydrate by a hydration reaction is used. In addition to the hydraulic alumina powder, the ceramic raw material powder is fired. The first mixed powder that becomes a multi-component ceramic in which ceramic components other than aluminum oxide (Al ₂ O ₃ ) and aluminum oxide (Al ₂ O ₃ ) are combined, or after firing, aluminum oxide (Al ₂ O ₃ ) A kneaded material for a ceramic structure, which is manufactured using a second mixed powder that is a ceramic composite in which a ceramic component other than aluminum oxide (Al ₂ O ₃ ) is dispersed.
(1) Hardness characteristics: 5-34mm
(2) Extrusion characteristics: 5cm or more

  Here, the above-mentioned “(2) Extrusion characteristic” means the length of the ceramic structure kneaded material extruded by the “extrusion test” described later.

[2] The ceramic structure kneaded material according to [1], wherein the hydraulic alumina powder is produced using an average particle diameter of 100 μm or less.

[3] The first mixed powder or the second mixed powder includes at least one powder selected from the group consisting of metal oxide powder, metal hydroxide powder, metal carbonate powder, and metal carbide powder. The kneaded clay for a ceramic structure according to the above [1] or [2], which is produced by using a material.

[4] The ceramic structure paste according to any one of [1] to [3], which is produced by kneading 100 parts by mass of the ceramic raw material powder and 5 to 200 parts by mass of water. .

[5] For a ceramic structure according to any one of [1] to [4], wherein the ceramic raw material powder and water are kneaded and then cured at a temperature of 10 to 200 ° C. Clay.

[6] A method for producing a ceramic structure kneaded material in which ceramic raw material powder and water are kneaded to obtain a ceramic structure kneaded material for use in the production of a ceramic structure, A ceramic alumina powder containing at least 1% by mass of a hydraulic alumina powder that forms a hydrate by a sum reaction is used. In addition to the hydraulic alumina powder, the ceramic raw material powder is baked and then aluminum oxide (Al ₂ O ₃ ) and a first mixed powder to be a first ceramic structure composed of a multi-component ceramic in which ceramic components other than aluminum oxide (Al ₂ O ₃ ) are combined, or after firing, aluminum oxide (Al ₂ O ₃₎ from the ceramic composite which ceramic component other than aluminum oxide (Al ₂ O ₃₎ was dispersed in Second second method of producing a ceramic structure for mixing soil using a mixed powder of a ceramic structure that.

[7] The method for producing a kneaded clay for a ceramic structure according to [6], wherein the hydraulic alumina powder having an average particle size of 100 μm or less is used.

[8] The first mixed powder or the second mixed powder includes at least one powder selected from the group consisting of metal oxide powder, metal hydroxide powder, metal carbonate powder, and metal carbide powder. The method for producing a kneaded clay for a ceramic structure according to [6] or [7], wherein a material is used.

[9] The method for producing a kneaded clay for a ceramic structure according to any one of [6] to [8], wherein 100 parts by mass of the ceramic raw material powder and 5 to 200 parts by mass of water are kneaded.

[10] The method for producing a kneaded clay for a ceramic structure according to any one of [6] to [9], wherein the ceramic raw material powder and water are kneaded and then cured at a temperature of 10 to 200 ° C.

[11] The method for producing a kneaded material for a ceramic structure according to any one of [6] to [10], wherein the obtained kneaded material for a ceramic structure has the following characteristics.
(1) Hardness characteristics: 5-34mm
(2) Extrusion characteristics: 5cm or more

  Here, the above-mentioned “(2) Extrusion characteristic” means the length of the ceramic structure kneaded material extruded by the “extrusion test” described later.

  According to the present invention, when used for the production of a ceramic structure (ceramic molded body before firing), it has excellent hardness characteristics and extrusion characteristics (high plasticity), so there is no special use of additives such as organic molding aids. In addition, it is possible to impart a desired shape to the ceramic molded body, which can reduce the cost by simplifying the molding process, and release of harmful gases during the heating process of the ceramic molded body, or complete thermal decomposition. Cement clay for ceramics structure and its efficiency, which can prevent residual carbon in organic ceramics from remaining in the ceramic structure, reduce environmental load and improve the quality of the resulting ceramic structure An exemplary manufacturing method is provided.

  Hereinafter, embodiments of the clay for ceramic structure of the present invention and the manufacturing method thereof will be described in detail.

The ceramic structure kneaded material of the present invention is a ceramic structure kneaded material used for producing a ceramic structure, which is produced by kneading ceramic raw material powder and water. A material containing at least 1% by mass of a hydraulic alumina powder that forms a hydrate by a sum reaction is used, and as a ceramic raw material powder, in addition to the hydraulic alumina powder, after firing, aluminum oxide (Al ₂ O ₃ ) and aluminum oxide (Al ₂ O ₃₎ other than the first mixed powder and the ceramic component is multi-component ceramic bonded, or after being calcined, aluminum oxide aluminum oxide _{(Al 2 O 3) (Al} 2 O ₃₎ ceramic components other than by using a second mixed powder comprising a ceramic composite body was dispersed produced It is those, and those having the following characteristics.
(1) Hardness characteristics: 5-34mm
(2) Extrusion characteristics: 5cm or more

Examples of the “hydraulic alumina powder that forms a hydrate by a hydration reaction” used in the present invention include ρ-alumina powder. Such a hydraulic alumina powder becomes aluminum oxide (Al ₂ O ₃ ) after firing.

  The hydraulic alumina powder is contained in the ceramic raw material powder at least 1% by mass, preferably at least 3% by mass, and more preferably at least 5% by mass. If it is less than 1% by mass, the above-mentioned characteristics ((1) hardness characteristics and (2) extrusion characteristics) (high plasticity) associated with the hydration reaction of hydraulic alumina will be insufficient, and ceramic molding with a desired shape will be performed. It becomes difficult to produce the body, and the strength characteristics become insufficient, and it becomes difficult to maintain the shape of the ceramic molded body.

  As such a hydraulic alumina powder, those having an average particle size of 100 μm or less are preferably used, more preferably 0.01 to 30 μm, and particularly preferably 0.01 to 5 μm. If the thickness exceeds 100 μm, the development of high plasticity is insufficient, and it may be difficult to produce a ceramic molded body having a desired shape, and the strength characteristics are insufficient, and it is difficult to maintain the shape of the ceramic molded body. It may become.

In the present invention, the ceramic raw material powder includes, in addition to the above-mentioned hydraulic alumina powder, ceramic components other than aluminum oxide (Al ₂ O ₃ ) and aluminum oxide (Al ₂ O ₃ ) after firing. A first mixed powder that becomes a bonded multi-component ceramic, or a ceramic composite in which ceramic components other than aluminum oxide (Al ₂ O ₃ ) are dispersed in aluminum oxide (Al ₂ O ₃ ) after firing. 2 mixed powder is used.

Examples of multi-component ceramics include mullite (3Al ₂ O ₃ .2SiO ₂ ), cordierite (2MgO.2Al ₂ O ₃ .5SiO ₂ ), and the like. Examples of the ceramic composite include those in which spinel (MgO.Al ₂ O ₃ ), silicon carbide (SiC), and the like are dispersed in an alumina grain boundary.

  Specific examples of the first mixed powder to be a multicomponent ceramic include a mixed powder for mullite ceramics composed of a hydraulic alumina powder and a silicon dioxide powder.

  As a specific example of the 2nd mixed powder used as a ceramic composite, the mixed powder for silicon carbide dispersion | distribution alumina ceramics which consists of a hydraulic alumina powder and a silicon carbide powder can be mentioned, for example.

  In the present invention, in order to obtain a ceramic structure having a desired composition, a metal oxide powder, a metal hydroxide powder, a metal carbonate powder, and a metal carbide powder are used as the first mixed powder or the second mixed powder. It is preferable to use a powder containing at least one powder selected from the group (hereinafter sometimes referred to as “metal compound powder”).

  In the first or second mixed powder, the average particle size of the powder constituting the first or second mixed powder is preferably 100 μm or less, and more preferably 0.01 to 30 μm. Preferably, it is 0.01-5 micrometers especially preferable. Further, the particle size before kneading the first or second mixed powder (for example, the above-described average particle diameter) is preferably finer, but when the pulverization is performed in the above-described range during the kneading process, coarse particles are used. It may be.

  A normal mixing method can be used for mixing the first or second mixed powder. However, when mixing by a wet method using water as a medium, it is preferable to end the mixing after the addition of water and before the start of curing with the amount of water described below, and after the addition of water and before the start of condensation. More preferably, mixing is terminated. Here, “curing” means that the mixed powder containing water loses fluidity, and “coagulation” means that the mixed powder containing water is stiff.

  In the present invention, it is preferable to knead 100 parts by mass of ceramic raw material powder and 5 to 200 parts by mass of water. It is more preferable to knead 100 parts by mass of the ceramic raw material powder and 10 to 200 parts by mass of water, and it is particularly preferable to knead 100 parts by mass of the raw material powder and 20 to 120 parts by mass of water. If the amount is less than 5 parts by mass, the high plasticity due to the hydration reaction of the hydraulic alumina becomes insufficient, making it difficult to produce a ceramic molded body of a desired shape, and the strength characteristics become insufficient, and the ceramic molding It may be difficult to maintain the shape of the body. Further, if it exceeds 200 parts by mass, it is difficult to condense and harden, so the expression of high plasticity becomes insufficient, and it may be difficult to produce a ceramic molded body of a desired shape, and the strength characteristics are insufficient. It may be difficult to maintain the shape of the ceramic molded body. In this case, even if it is a case where it knead | mixes using the water exceeding 200 mass parts, the water | moisture content of the kneaded clay for ceramic structures finally prepared should just be 200 mass parts or less.

  For the purpose of adjusting the amount of water used while maintaining the fluidity of the ceramic structure kneaded material, for example, a water reducing agent such as lignin sulfonate or polycarboxylate may be used.

  The ceramic structure kneaded material of the present invention has excellent plasticity only by the constitution of itself (ceramic raw material powder and water) without specially blending other components. For this reason, it is necessary to further add organic molding aids (organic binders) such as polyvinyl alcohol and methylcellulose, which have been added for the purpose of maintaining the shape and strength of the ceramic molded body as in the past. There is no. However, it does not exclude the use of the above-mentioned organic molding aid (organic binder) depending on the purpose of use (for example, when it is necessary to further improve the strength of the ceramic molded body).

  In general, in the case of kaolinite clay, which is conventionally used as a raw material for ordinary ceramics, the explanation of plasticity is explained by Mr. Noki and Mr. Okuda (Ceramics Raw Materials Vol. 4, 99-106, 1952, Clay Science) , 8, 14-23, 1968), a. The particles are fine and close to the colloidal region, b. Its shape is flat; c. For example, the water film on the particle surface (due to hydrogen bonding) is thicker than water. However, it has been pointed out that the essence of the cause of this plasticity has many unsolved problems. The cause of the plasticity like the clay of the clay for ceramic structure produced according to the present invention is unknown, but may satisfy any of the above-mentioned a to c.

  In this invention, after knead | mixing ceramic raw material powder and water, it is preferable to cure in the atmosphere which is not dried at the temperature of 10-200 degreeC. The temperature for curing is more preferably room temperature to 60 ° C. When the temperature is lower than 10 ° C., high plasticity due to the hydration reaction of hydraulic alumina becomes insufficient, and it may be difficult to produce a ceramic molded body having a desired shape. If it exceeds 200 ° C., the heat energy cost is increased.

  The kneaded clay for a ceramic structure of the present invention has a hardness of 5 to 34 mm, preferably 18 to 34 mm, more preferably 20 to 30 mm as (1) hardness characteristics. When the thickness is less than 5 mm, the ceramic molded body produced from the ceramic structure clay is deformed by its own weight. When it exceeds 34 mm, workability at the time of producing a ceramic molded body is lowered.

  The kneaded clay for ceramic structure of the present invention has (2) Extrusion characteristics (measured value of the length of the extruded dough when the dough is extruded into a noodle-like shape with a diameter of 3 mm in the “extrusion test” described later. ) As an extrusion property of 5 cm or more, preferably 10 cm or more. If it is less than 5 cm, it becomes difficult to easily prepare a ceramic molded body having a desired shape.

  Since the clay for ceramic structure of the present invention has both hardness suitable for molding operation and excellent extrusion characteristics, a ceramic molded body having a desired shape can be easily prepared by, for example, extrusion molding. The definition of hardness in (1) hardness characteristics and evaluation in (2) extrusion characteristics will be described later.

  “Hardness” in the ceramic structure kneaded material of the present invention is “hardness-related” measured in accordance with the hardness measuring method of plastic clay (plastic kneaded material) described in JP-A-2003-89575. It means “indicator”. That is, FIG. 1 (drawing schematically explaining a method for measuring hardness of a dough using a hardness meter, (a) is an overall view of the hardness meter, (b) is a measurement state when the dough is soft, ( (c) is a measurement state when the kneaded clay is hard), FIG. 2 (a graph showing the spring properties of the spring material 2 to be used) and FIG. 3 (an enlarged view showing the shape and dimensions of the tip of the hardness meter). As shown in FIG. 1, the hardness meter 1 is configured by connecting a conical tip portion 4 and a support portion 3 by a spring material 2 and housing them in a cylindrical sheath portion 5 ( FIG. 1 (a)). When measuring the hardness of the ceramic structure kneaded material of the present invention, first, the tip 4 of the hardness meter 1 is inserted vertically into the kneaded materials 6 and 7 until the sheath 5 contacts. Next, the length (d1, d2) of the support part 3 protruding above the sheath part 5 is read, and the numerical value (mm) at this time is defined as the hardness of the dough 6,7. Therefore, the larger the numerical value, the higher the hardness of the kneaded clays 6 and 7, which means that they are harder. L0, L1, and L2 indicate the length of the spring material 2.

  A ceramic molded body can be produced by molding the kneaded clay for a ceramic structure of the present invention into a predetermined shape. As a method for producing such a ceramic molded body, a normal method can be used. For example, extrusion molding etc. can be mentioned. By using the clay for a ceramic structure of the present invention, it is possible to impart a desired shape to the ceramic molded body without using an additive such as an organic molding aid. Although there is no restriction | limiting in particular as a shape of a ceramic molded body, For example, plate shape, a column shape, etc. can be mentioned.

  Further, the ceramic molded body can be dried and fired to produce a ceramic structure. These methods can be ordinary methods. For example, normal pressure sintering can be mentioned. In this case, if cracks and warpage do not occur, the ceramic molded body may be dried and fired independently or in series.

  The firing temperature is preferably 1200 to 1700 ° C. More preferably, it is 1400-1600 degreeC. If the temperature is lower than 1200 ° C., the ceramic structure constituting particles may not be completely formed. On the other hand, when the temperature exceeds 1700 ° C., the thermal energy cost is increased, and the constituent particles grow too much due to oversintering, which may reduce the strength. Although baking time changes with heating temperature, 0.5 to 10 hours are preferable, More preferably, it is 1 to 6 hours, Most preferably, it is 2 to 4 hours. If it is less than 0.5 hour, the constituent particles may not be completely formed. If it exceeds 10 hours, the thermal energy cost is increased, and the constituent particles grow too much due to oversintering, and the strength may be lowered.

  A ceramic structure from dense to porous can be manufactured by using a ceramic structure kneaded material in which the amount of hydraulic alumina powder in the ceramic raw material powder and the amount of water are appropriately adjusted within the above range. .

  The ceramic structure of the present invention is a high-quality structure manufactured by the above-described method. For example, because it is of high quality with excellent characteristics such as heat resistance, corrosion resistance, thermal shock resistance, and mechanical strength, it is effective in various industrial fields that use structural parts and electronic parts that require these characteristics. Used for.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited at all by these. In addition, the characteristic (plasticity) of the kneaded clay for ceramics structure is the hardness measured in accordance with the hardness measuring method of the plastic clay (plastic dough) described in JP-A-2003-89575 as described above. And the visual observation (hereinafter sometimes referred to as “extrusion test”) when the ceramic structure kneaded material was extruded into a noodle-like shape having a diameter of 3 mm. Specifically, as shown in FIGS. 4A and 4B, the above-described “extrusion test” is performed by applying a load to the push rod 15 using a universal testing machine after filling the mold 13 with the sample 11. The length of the clay 8 extruded from the hole 17 having a diameter of 3 mm was measured, and the shape was visually observed. For reference, as shown in FIGS. 4C and 4D, after the sample 14 is filled with the sample 12, a load is applied to the push bar 16 using a universal testing machine, and the hole 18 having a diameter of 1 mm is applied. The length of the extruded clay 9 was measured and the shape was also visually observed.

  In Comparative Example 1, the plasticity of the kaolinite natural clay for ceramics was evaluated by the hardness and the extrusion test, which is superior to the plasticity of the kaolinite natural clay for ceramics at present and becomes a ceramic structure after firing. Since there is no highly plastic material, the plasticity evaluation result of kaolinite natural clay for ceramics is used for comparison with the present invention.

  Moreover, in the following Examples 1-2, as a raw material powder for ceramics, a cordier composed of a raw material powder for mullite ceramics composed of hydraulic alumina and silicon dioxide, and a mixed powder of hydraulic alumina, silicon dioxide and magnesium oxide. The example using the raw material powder for light ceramics is shown. Further, in Comparative Examples 2 to 4, cordierite ceramics comprising mullite ceramic raw material powder comprising α-alumina and silicon dioxide, and cordierite ceramic comprising alpha-alumina, mixed powder of silicon dioxide and magnesium oxide as the ceramic raw material powder. An example using a raw material powder is shown.

(Example 1)
Thermal analysis up to 1400 ° C. of hydraulic alumina (trade name: BK-105, average particle size: 3.65 μm, manufactured by Sumitomo Chemical Co., Ltd.) was performed, and the mass reduction rate due to dehydration of hydraulic alumina was measured. It was 8.4% by mass. In an alumina container having an inner diameter of 75 mm and an inner volume of 300 cm ³ , hydraulic alumina and reagent-grade silicon dioxide are 73.5 parts by mass (29.4 g) and 26.5 parts by mass (10.6 g), respectively. Adjusted filling as follows. At this time, the hydraulic alumina was weighed in consideration of the dehydration accompanying the aforementioned heating. Further, 300 g of α-alumina balls having 99.9% by mass of Al ₂ O ₃ and 160 g of ethyl alcohol were filled, and wet mixing was performed at 250 rpm for 0.5 hours using a planetary ball mill. The obtained slurry was dried at 60 ° C. under reduced pressure, and the whole amount was passed through a 100-mesh sieve to prepare raw powder for mullite ceramics (2 batches, corresponding to a total of 80 g).

  To 100 parts by mass (60 g) of the raw material powder for mullite ceramics prepared as described above, 65 parts by mass (39 g) of distilled water was added, and after kneading, it was filled in a sealed container. Then, when it left still with a 25 degreeC thermostat for 48 hours, the whole hardened | cured by the hydration reaction of hydraulic alumina. The sample was taken out from the sealed container and measured for hardness, which was 25 mm. Moreover, when a sample was filled in a mold having a hole with a diameter of 3 mm at the bottom and extruded using a universal testing machine, a noodle-shaped noodle-shaped clay with a diameter of 3 mm without scratches or cracks was continuously 11 cm. And pushed out. Furthermore, when a sample having a 1 mm diameter hole at the bottom was filled with a sample and extruded using a universal testing machine, a 12 mm continuous mullite ceramic paste with a diameter of 1 mm without scratches or cracks was obtained. And pushed out.

(Example 2)
36.9 parts by mass (14.8 g), 49.8 parts by mass (19.9 g), and 13.4 parts by mass (5. 5 parts) of hydraulic alumina, reagent-grade silicon dioxide, and reagent-grade magnesium oxide, respectively. 4 g) was adjusted and filled. At this time, as in the case of Example 1, the hydraulic alumina was weighed in consideration of dehydration accompanying heating. Furthermore, the same operation as in Example 1 was performed to prepare a raw powder for cordierite ceramics.

  60 parts by mass (36 g) of distilled water was added to 100 parts by mass (60 g) of the raw material powder for cordierite ceramics prepared as described above, and the mixture was kneaded and filled into a sealed container. Then, when it left still with a 25 degreeC thermostat for 48 hours, the whole hardened | cured by the hydration reaction of hydraulic alumina. The sample was taken out from the sealed container and measured for hardness, which was 20 mm. In addition, when a sample having a hole with a diameter of 3 mm in the bottom was filled with a sample and extruded using a universal testing machine, a 3 mm-diameter noodle-shaped ceramic structure paste without cracks and cracks was 12 cm. Extruded continuously. Furthermore, when a sample having a hole with a diameter of 1 mm at the bottom was filled with a sample and extruded using a universal testing machine, a cordierite ceramic paste with a diameter of 1 mm and no scratches or cracks was found to be 13 cm. Extruded continuously.

  A part (0.019 g) of the cordierite ceramic molded body produced in Example 2 was analyzed for gas generated in the heating process up to 1000 ° C. The generated gas species and the generated intensity at 272 ° C., which generated the largest amount of gas, were measured. As a result, water having a mass number of 18 was mainly detected. Furthermore, the generation intensity of gas considered to be a hydrocarbon system having a large mass number other than water having a mass number of 18 was low. The result is shown in FIG.

(Comparative Example 1)
It was 23 mm when the hardness of the kaolinite natural clay for ceramics was measured. In addition, a kaolinite natural clay filled in a mold with a hole with a diameter of 3 mm at the bottom and extruded using a universal testing machine, a kaolinite natural with a 3 mm diameter noodle shape without scratches or cracks. Clay was extruded 13cm continuously. Furthermore, when a mold having a hole with a diameter of 1 mm at the bottom is filled with kaolinite natural clay and extruded using a universal testing machine, 13 cm of kaolinite natural clay having a 1 mm diameter noodle-like shape continues. And pushed out.

(Comparative Example 2)
71.8 parts by mass (28.7 g) and 28.2 parts by mass of α-alumina (trade name: TMDAR, average particle size: 0.2 μm, manufactured by Daimei Chemical Co., Ltd.) and reagent-grade silicon dioxide, respectively. Adjustment filling was carried out so that it might become (11.3g). Further, 300 g of α-alumina balls having 99.9% by mass of Al ₂ O ₃ and 160 g of ethyl alcohol were filled, and wet mixing was performed at 250 rpm for 0.5 hours using a planetary ball mill. The obtained slurry was dried at 60 ° C. under reduced pressure, and then passed through a 100-mesh sieve to prepare a raw material powder for mullite ceramics (3 batches, equivalent to 120 g).

  30 parts by mass (30 g) of distilled water was added to 100 parts by mass (100 g) of the raw material powder for mullite ceramics prepared as described above, and the mixture was kneaded and filled into a sealed container. Then, when it left still for 48 hours with a 25 degreeC thermostat, the whole did not harden | cure. When taken out from the sealed container and measured for hardness, it was 0 mm. Moreover, when a sample having a hole with a diameter of 3 mm in the bottom was filled with a sample and extruded using a universal testing machine, a paste-like sample was intermittently extruded from the hole. The extruded sample could not maintain the shape immediately after passing through the hole. Furthermore, when a sample having a hole with a diameter of 1 mm at the bottom was filled with a sample and extruded using a universal testing machine, a paste-like sample was intermittently extruded from the hole. The extruded sample could not maintain the shape immediately after passing through the hole.

(Comparative Example 3)
34.9 parts by mass (14.0 g), 51.4 parts by mass (20.6 g), and 13.8 parts by mass of α-alumina, reagent-grade silicon dioxide, and reagent-grade magnesium oxide (5. 5g) was adjusted and filled. The same operation as in Comparative Example 2 was performed to prepare a raw material powder for cordierite ceramics.

  30 parts by mass (30 g) of distilled water was added to 100 parts by mass (100 g) of the raw material powder for cordierite ceramics prepared as described above, and the mixture was kneaded and filled into a sealed container. Then, when it left still for 48 hours with a 25 degreeC thermostat, the whole did not harden | cure. When taken out from the sealed container and measured for hardness, it was 0 mm. Moreover, when a sample having a hole with a diameter of 3 mm in the bottom was filled with a sample and extruded using a universal testing machine, a paste-like sample was intermittently extruded from the hole. The extruded sample could not maintain the shape immediately after passing through the hole. Furthermore, when a sample having a hole with a diameter of 1 mm at the bottom was filled with a sample and extruded using a universal testing machine, a paste-like sample was intermittently extruded from the hole. The extruded sample could not maintain the shape immediately after passing through the hole.

(Comparative Example 4)
To 100 parts by mass (30 g) of the raw powder for mullite ceramics used in Comparative Example 2, 8 parts by mass of methylcellulose (2.4 g) and 30 parts by mass of distilled water (9 g) are added as an organic binder, and in an alumina mortar. A part of the kneaded material (0.015 g) prepared by sufficiently kneading was subjected to the same measurement as in Example 2. As a result, at 360 ° C. with the largest gas generation amount, a gas considered to be a hydrocarbon system having a large mass number other than water having a mass number of 18 was detected with high generation intensity. These results are shown in FIG.

  The dough for ceramic structure of the present invention has excellent hardness characteristics and extrusion characteristics (high plasticity), and is a high quality ceramic structure excellent in characteristics such as heat resistance, electrical insulation and mechanical strength. Can be provided in a simple, low environmental load and low cost, and is effectively used in various industrial fields using structural parts, electronic parts, and the like that require these characteristics.

It is explanatory drawing which shows typically the hardness measuring method of the clay for ceramics structures using a hardness meter, FIG.1 (a) is the whole hardness meter, FIG.1 (b) is the clay for ceramics structure soft. FIG. 1C shows the measurement state when the ceramic structure kneaded clay is hard. It is an enlarged view which shows typically the shape-dimension of the front-end | tip part of a hardness meter. It is a graph which shows the spring property of a spring material. FIG. 4 (a) is an explanatory view schematically showing an extrusion test, in which FIG. 4 (a) is a state in which the bottom hole is filled with a clay for ceramic structure in an extrusion test using a mold having a diameter of 3 mm, and FIG. 4 (b) is a bottom portion. Fig. 4 (c) shows the extruded state of the clay for ceramic structure in an extrusion test using a mold having a 3 mm diameter hole. Fig. 4 (d) shows the state of filling the soil, and the state of extrusion of the ceramic structure kneaded material in an extrusion test using a mold having a 1 mm diameter hole at the bottom. It is a graph which shows the generated gas-mass spectrometry result in 272 degreeC in Example 2. FIG. It is a graph which shows the generated gas-mass analysis result in 360 degreeC in the comparative example 4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Hardness meter, 2 ... Spring material, 3 ... Support part, 4 ... Front-end | tip part, 5 ... Sheath part, 6, 7, 8, 9 ... Kneaded clay for ceramic structures, 11, 12 ... Sample, 13, 14 ... Mold, 15, 16 ... push rod, 17, 18 ... hole.

Claims (11)

A ceramic structure kneaded material used for producing a ceramic structure produced by kneading ceramic raw material powder and water,
As the ceramic raw material powder, a powder containing at least 1% by mass of a hydraulic alumina powder that forms a hydrate by a hydration reaction,
As the ceramic raw material powder, in addition to the hydraulic alumina powder, after being fired, and the multi-component system ceramics and a ceramic component other than aluminum oxide (Al ₂ O ₃₎ and aluminum oxide (Al ₂ O ₃₎ is bonded Or a second mixed powder that becomes a ceramic composite in which a ceramic component other than aluminum oxide (Al ₂ O ₃ ) is dispersed in aluminum oxide (Al ₂ O ₃ ) after firing. A kneaded clay for a ceramic structure which is manufactured and has the following characteristics.
(1) Hardness characteristics: 5-34mm
(2) Extrusion characteristics: 5cm or more   2. The ceramic structure paste according to claim 1, wherein the hydraulic alumina powder is manufactured using a powder having an average particle diameter of 100 μm or less.   As the first mixed powder or the second mixed powder, a powder containing at least one powder selected from the group consisting of metal oxide powder, metal hydroxide powder, metal carbonate powder and metal carbide powder is used. The ceramic structure paste according to claim 1 or 2, wherein the ceramic structure paste is produced.   The ceramic structure paste according to any one of claims 1 to 3, which is produced by kneading 100 parts by mass of the ceramic raw material powder and 5 to 200 parts by mass of water.   The kneaded material for ceramic structure according to any one of claims 1 to 4, which is produced by kneading the ceramic raw material powder and water and then curing at a temperature of 10 to 200 ° C. A method for producing a ceramic structure kneaded material in which a ceramic raw material powder and water are kneaded to obtain a ceramic structure kneaded material used for producing a ceramic structure,
As the ceramic raw material powder, a powder containing at least 1% by mass of a hydraulic alumina powder that forms a hydrate by a hydration reaction,
As the ceramic raw material powder, in addition to the hydraulic alumina powder, after being fired, and the multi-component system ceramics and a ceramic component other than aluminum oxide (Al ₂ O ₃₎ and aluminum oxide (Al ₂ O ₃₎ is bonded Ceramics using the first mixed powder or the second mixed powder that becomes a ceramic composite in which a ceramic component other than aluminum oxide (Al ₂ O ₃ ) is dispersed in aluminum oxide (Al ₂ O ₃ ) after firing. A method for producing a kneaded clay for a structure.   The method for producing a kneaded clay for a ceramic structure according to claim 6, wherein the hydraulic alumina powder having an average particle diameter of 100 µm or less is used.   As the first mixed powder or the second mixed powder, a powder containing at least one powder selected from the group consisting of metal oxide powder, metal hydroxide powder, metal carbonate powder and metal carbide powder is used. The manufacturing method of the kneaded clay for ceramic structures of Claim 6 or 7.   The method for producing a kneaded clay for a ceramic structure according to any one of claims 6 to 8, wherein 100 parts by mass of the ceramic raw material powder and 5 to 200 parts by mass of water are kneaded.   The method for producing a kneaded clay for a ceramic structure according to any one of claims 6 to 9, wherein the ceramic raw material powder and water are kneaded and then cured at a temperature of 10 to 200 ° C. The method for producing a kneaded material for a ceramic structure according to any one of claims 6 to 10, wherein the obtained kneaded material for a ceramic structure has the following characteristics.
(1) Hardness characteristics: 5-34mm
(2) Extrusion characteristics: 5cm or more

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