JP2017190274A - Inorganic colloid-containing liquid, composition for inorganic fiber molded body and inorganic fiber molded body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inorganic fiber molded body containing clay minerals and capable of suppressing reduction of internal hardness and increase of burning shrinkage, a composition liquid for inorganic fiber molded body suitable for obtaining the same and an inorganic colloid-containing liquid.SOLUTION: An inorganic colloid-containing liquid contains water, inorganic colloid and saponite. A composition liquid for inorganic fiber molded body contains the inorganic colloid-containing liquid and inorganic fibers. The inorganic fiber molded body contains the inorganic fibers, the inorganic colloid and the saponite. The saponite has preferably Fe content of 1.3% or less by atom percentage. The content of the saponite in the inorganic colloid-containing liquid is preferably 0.1-4 pts.mass based on 100 pts.mass of water. The content of the saponite in the inorganic fiber molded body is preferably 0.3-5.7 pts.mass based on 100 pts.mass of the inorganic fibers.SELECTED DRAWING: None

Description

  The present invention relates to an inorganic colloid-containing liquid, an inorganic fiber molded body composition liquid, and an inorganic fiber molded body.

  Conventionally, for example, an inorganic fiber molded body having a plate shape, a cylindrical shape, a bowl shape, or the like having a thickness of about several mm to 150 mm has been used for heat insulation applications such as a furnace. This type of inorganic fiber molded body is manufactured, for example, by molding and drying a slurry containing water, an inorganic colloid, an organic substance, and inorganic fibers. The organic substance added to the slurry is usually added for the purpose of suppressing the migration of the inorganic colloid to the surface of the molded body during drying and making the hardness of the inorganic fiber molded body uniform.

  However, an inorganic fiber molded body containing an organic material has a drawback that smoke is generated by firing at the first use. Therefore, a method for suppressing the migration of inorganic colloid using a clay mineral instead of an organic substance has been proposed. For example, Patent Document 1 discloses an inorganic fiber molded body using montmorillonite as a clay mineral.

Japanese Patent Publication No.61-37228

  However, the prior art has problems in the following points. That is, an inorganic colloid-containing liquid containing water, an inorganic colloid, and a clay mineral such as montmorillonite, when the amount of clay mineral is large, an inorganic fiber is added to prepare an inorganic fiber molded body composition liquid. The viscosity of the molding composition liquid tends to increase greatly. Therefore, the moldability of the composition liquid for inorganic fiber molded body deteriorates, and in some cases, the molding becomes difficult. Furthermore, clay minerals usually contain an alkali component. Therefore, an inorganic fiber molded body obtained by molding and drying an inorganic fiber molded body composition liquid containing a large amount of clay mineral such as montmorillonite has an increased firing shrinkage ratio due to firing during use. Since the increase in the firing shrinkage ratio causes a gap after the construction, it tends to be a quality problem particularly for an inorganic fiber molded body for heat insulation.

  On the other hand, when the amount of the clay mineral such as montmorillonite is small, it becomes difficult to suppress the migration of the inorganic colloid, and the internal hardness of the obtained inorganic fiber molded body is lowered. This is because the hardness of only the surface appears due to the migration of the inorganic colloid. When internal hardness falls, the workability by processes, such as drilling, will worsen, and the workability of an inorganic fiber molded object will fall. The migration of the inorganic colloid is not so much seen when the thickness of the inorganic fiber molded body is several mm, but an obvious difference is seen from the thickness of the inorganic fiber molded body of about 10 mm. The thicker the film becomes, the more prominent it becomes.

  The present invention has been made in view of the above background, and includes an inorganic fiber molded body that includes a clay mineral, can suppress a decrease in internal hardness, and can suppress an increase in firing shrinkage rate, It is an object of the present invention to provide an inorganic fiber molded body composition liquid and an inorganic colloid-containing liquid suitable for obtaining this.

  One aspect of the present invention resides in an inorganic colloid-containing liquid containing water, an inorganic colloid, and saponite.

  Another aspect of the present invention resides in an inorganic fiber molded body composition liquid comprising the inorganic colloid-containing liquid and inorganic fibers.

  Still another embodiment of the present invention is an inorganic fiber molded body containing inorganic fibers, inorganic colloids, and saponite.

  The inorganic colloid-containing liquid contains saponite as a clay mineral. Therefore, the inorganic colloid-containing liquid can suppress the migration of the inorganic colloid with a small amount of clay mineral as compared with the conventional inorganic colloid-containing liquid containing montmorillonite or the like which is the same clay mineral. Therefore, an inorganic fiber is mixed with the inorganic colloid-containing liquid to prepare an inorganic fiber molded body composition liquid containing the inorganic colloid-containing liquid and the inorganic fiber, and this is molded and dried to obtain an inorganic fiber molded body. When produced, the migration of inorganic colloid to the surface of the molded body during drying is suppressed with a smaller amount of clay mineral than before. Therefore, even if clay minerals are included, the decrease in internal hardness due to the migration of inorganic colloids can be suppressed, and the increase in the firing shrinkage rate due to the increase in alkali amount due to clay minerals can be suppressed. An inorganic fiber molded body that can be obtained is obtained. In addition, the inorganic colloid-containing liquid can be formed with a small amount of clay mineral even when a composition liquid for inorganic fiber molded body is prepared by adding more inorganic fibers compared to the conventional inorganic colloid-containing liquid. An increase in the viscosity of the composition liquid can be suppressed. Therefore, the composition liquid for inorganic fiber moldings which can ensure moldability easily is obtained.

  The inorganic fiber molded body composition liquid includes the inorganic colloid-containing liquid using saponite as a clay mineral. For this reason, when an inorganic fiber molded body is produced by molding and drying the inorganic fiber, the decrease in internal hardness can be suppressed and the increase in the firing shrinkage rate can be suppressed for the reasons described above. A molded body is obtained.

  The inorganic fiber molded body uses saponite as a clay mineral. Therefore, the said inorganic fiber molded object can suppress the fall of internal hardness for the reason mentioned above, and can suppress the increase in a baking shrinkage rate.

It is an X-ray diffraction pattern of the clay mineral used in the Example.

  The inorganic colloid-containing liquid, the inorganic fiber molded body composition liquid, and the inorganic fiber molded body will be described.

  The said inorganic colloid containing liquid is demonstrated.

  The inorganic colloid-containing liquid contains water, an inorganic colloid, and saponite.

  Examples of inorganic colloids include colloidal silica, colloidal alumina, colloidal zirconia, and colloidal titania. These can be used alone or in combination of two or more. Specifically, colloidal silica and colloidal alumina are suitable as the inorganic colloid. These are prepared by mixing an inorganic fiber with an inorganic colloid-containing liquid to prepare an inorganic fiber molded body composition liquid containing the inorganic colloid-containing liquid and the inorganic fiber, and molding and drying the liquid composition. This is because the function of the molded body as a curing binder is sufficient and easy to obtain.

  In the inorganic colloid-containing liquid, the saponite may have an Fe content of 1.3% or less in terms of atomic ratio.

In this case, the migration suppression effect of the inorganic colloid can be increased.
Therefore, when an inorganic fiber molded body composition liquid is prepared using this inorganic colloid-containing liquid and an inorganic fiber molded body is produced, an inorganic fiber molded body having sufficient internal hardness is obtained. In addition, the Fe content of saponite can be measured using a fluorescent X-ray analysis method.

  From the viewpoint of increasing the migration suppression effect of the inorganic colloid, the Fe content of the saponite is preferably 1.2% or less, more preferably 1.1% or less, and even more preferably 1.0% or less in terms of atomic ratio. Even more preferably, it can be 0.8% or less, and still more preferably 0.6% or less. In addition, it is desirable that the saponite does not contain Fe (Fe content is 0%) from the viewpoint of further increasing the migration suppression effect of the inorganic colloid. As the saponite, preferably, saponite derived from artificial synthesis can be suitably used. This is because artificially derived saponite is easier to reduce the Fe content than saponite derived from natural minerals.

  In the inorganic colloid-containing liquid, the saponite content is preferably 0.1 to 4 parts by mass with respect to 100 parts by mass of water.

  In this case, an inorganic fiber molded body composition liquid is prepared using this inorganic colloid-containing liquid, and when forming an inorganic fiber molded body, ensuring the moldability of the inorganic fiber molded body composition liquid, inorganic fiber molding Ensuring the internal hardness of the body can be ensured.

  In the inorganic colloid-containing liquid, the content of saponite is preferably 0.14 parts by mass or more, more preferably 0.15 parts by mass or more with respect to 100 parts by mass of water, from the viewpoint of ensuring the addition effect. Even more preferably, it can be 0.2 parts by mass or more. On the other hand, in the inorganic colloid-containing liquid, the saponite content can be 2 parts by mass or less with respect to 100 parts by mass of water. In this case, it becomes easy to obtain an inorganic fiber molded body composition liquid having a viscosity suitable for suction molding. In this case, the content of saponite is preferably 1.8 parts by mass or less, more preferably 1.5 parts by mass or less, further preferably 1.3 parts by mass with respect to 100 parts by mass of water from the viewpoint of suction moldability. Part or less.

  Moreover, in the said inorganic colloid containing liquid, content of a saponite can also be made into 2 mass parts-4 mass parts or less with respect to 100 mass parts of water. When the content of saponite is more than 2 parts by mass to 3 parts by mass or less with respect to 100 parts by mass of water, there is a tendency that the composition liquid for inorganic fiber molded body becomes a sol in a stationary state. Further, when the content of saponite is more than 3 parts by mass to 4 parts by mass or less with respect to 100 parts by mass of water, the composition liquid for inorganic fiber molded body becomes a gel state in a stationary state, By doing so, there is a tendency that the composition liquid for inorganic fiber molded body becomes sol. Therefore, the composition liquid for inorganic fiber molded body in which the content of saponite is more than 2 parts by mass to 4 parts by mass or less with respect to 100 parts by mass of water is mainly used for press molding with a large allowable range for viscosity increase. it can. In addition, press molding as used in this specification means shape | molding the composition liquid for inorganic fiber molded objects by press, and after carrying out the suction molding of the composition liquid for inorganic fiber molded objects, and demolding, it is as needed. It is different from the press that may be performed.

  In the inorganic colloid-containing liquid, the content of the inorganic colloid is preferably 4 to 67 parts by mass with respect to 100 parts by mass of water.

  In this case, a composition liquid for an inorganic fiber molded body is prepared using this inorganic colloid-containing liquid, and when the inorganic fiber molded body is produced, the stability of the inorganic colloid can be easily maintained. Easy to improve hardness.

  In the inorganic colloid-containing liquid, the content of the inorganic colloid is preferably 5 parts by mass or more with respect to 100 parts by mass of water from the viewpoint that it is easy to secure the internal hardness of the inorganic fiber molded body by suction molding. Preferably it is 6 parts by mass or more, more preferably 7 parts by mass or more, even more preferably 8 parts by mass or more, and even more preferably 10 parts by mass or more. On the other hand, in the inorganic colloid-containing liquid, the content of the inorganic colloid is preferably 60 parts by mass or less, more preferably 50 parts by mass with respect to 100 parts by mass of water from the viewpoint of easily ensuring the stability of the inorganic colloid. The amount can be not more than mass parts, more preferably not more than 40 mass parts. Furthermore, in the said inorganic colloid containing liquid, content of an inorganic colloid can be 20 mass parts or less with respect to 100 mass parts of water. In this case, it is easy to obtain an inorganic fiber molded body having a low specific gravity and a high internal hardness by suction molding the composition for inorganic fiber molded body. In this case, from the viewpoint of increasing the effect, the content of the inorganic colloid is preferably 19 parts by mass or less, more preferably 18 parts by mass or less, and even more preferably 17 parts by mass or less with respect to 100 parts by mass of water. Even more preferably, it can be 16 parts by mass or less, still more preferably 15 parts by mass or less.

  The inorganic colloid-containing liquid preferably contains no organic substance, or the organic substance content is 1 part by mass or less with respect to 100 parts by mass of water.

  Organic substances are effective in suppressing migration of inorganic colloids. However, when an inorganic fiber molded body composition liquid is prepared using an inorganic colloid-containing liquid with an excessive content of organic matter and an inorganic fiber molded body is produced, smoke is generated when fired at the first use of the inorganic fiber molded body. Is generated in large quantities. When the content of the organic substance in the inorganic colloid-containing liquid is within the above range, the generation of smoke can be suppressed within an allowable range. When the inorganic colloid-containing liquid contains an organic substance, the organic substance content is preferably 0.8 parts by mass or less with respect to 100 parts by mass of water from the viewpoint of easily suppressing the generation of the smoke. More preferably, it is 0.5 mass part or less, More preferably, it is 0.3 mass part or less, More preferably, it can be 0.1 mass part or less. In particular, when the inorganic colloid-containing liquid does not contain an organic substance, the generation of smoke can be eliminated, and the usefulness of the inorganic colloid-containing liquid is increased. Examples of the organic substance used for suppressing migration of the inorganic colloid include polymers such as a cationic polymer and an anionic polymer, and agar.

  Next, the said composition liquid for inorganic fiber molded objects is demonstrated.

  The inorganic fiber molded body composition liquid contains the inorganic colloid-containing liquid and inorganic fibers.

As the inorganic fibers, for example, the ceramic fibers in chemical composition comprising _Al 2 _{O 3} and SiO ₂ can be suitably used. The ceramic fiber is an inorganic refractory fiber having a basic composition of Al ₂ O ₃ and SiO ₂ as defined by the Ceramic Fiber Industry Association. More specifically, examples of the inorganic fiber include refractory ceramic fiber and alumina fiber. These can be used alone or in combination of two or more. Furthermore, although it is a component system different from the inorganic fiber, a refractory inorganic fiber containing SiO ₂ and an alkali metal oxide or SiO ₂ and an alkaline earth metal oxide can be used in the same manner. In addition, as an inorganic fiber which has this as a basic composition, a biosoluble fiber etc. can be illustrated more specifically, for example. These may be used alone or in combination of two or more, and may be used in combination with inorganic fibers having a basic composition of Al ₂ O ₃ and SiO ₂ . In this specification, alumina fiber is used in a broad sense, and includes not only alumina fiber but also mullite fiber. In addition, biosoluble fiber is superior to refractory ceramic fiber and alumina fiber, which are non-biosoluble fibers, in solubility in the living body. Therefore, inorganic colloid-containing liquid, composition liquid for inorganic fiber molded body, and inorganic fiber There is an advantage in improving the manufacturing environment of the molded body.

  In the composition liquid for inorganic fiber molded body, the content of inorganic fibers can be 25 parts by mass or less with respect to 100 parts by mass of the inorganic colloid-containing liquid.

  In this case, a composition liquid for inorganic fiber molded body excellent in moldability of the inorganic fiber molded body by suction molding can be obtained. Therefore, in this case, an inorganic fiber molded body that can suppress a decrease in internal hardness and suppress an increase in the firing shrinkage rate can be obtained by highly productive suction molding.

  In this case, from the viewpoint of easily obtaining the effect, the content of the inorganic fiber is preferably 23 parts by mass or less, more preferably 20 parts by mass or less, further preferably 100 parts by mass with respect to 100 parts by mass of the inorganic colloid-containing liquid. It can be 18 parts by mass or less, and more preferably 15 parts by mass or less. In addition, from the viewpoint of ensuring the formation of the inorganic fiber molded body, the content of the inorganic fiber can be 0.5 parts by mass or more with respect to 100 parts by mass of the inorganic colloid-containing liquid.

  In addition, in the composition liquid for inorganic fiber molded body, the content of the inorganic fiber can be more than 25 parts by mass to 300 parts by mass with respect to 100 parts by mass of the inorganic colloid-containing liquid.

  In this case, a composition liquid for inorganic fiber molded body excellent in moldability of the inorganic fiber molded body by press molding can be obtained. Therefore, in this case, the inorganic fiber that can suppress the decrease in internal hardness and suppress the increase in the shrinkage of firing by press molding, in which the composition design of the molded body is easier than the suction molding. A molded body is obtained.

  In addition, when the inorganic fiber molded body composition liquid is dehydrated and dehydrated by pressing, or when the inorganic fiber molded body composition liquid is dehydrated and dehydrated by suction while pressing, The content of the inorganic fiber is not particularly limited, and any of the above-described inorganic fiber molded body composition liquids suitable for suction molding and press molding can be used.

  In this case, from the viewpoint of easily obtaining the effect, the content of the inorganic fiber is preferably 250 parts by mass or less, more preferably 200 parts by mass or less, and still more preferably with respect to 100 parts by mass of the inorganic colloid-containing liquid. It can be 150 parts by mass or less, and more preferably 100 parts by mass or less.

  In addition, the composition liquid for an inorganic fiber molded body can contain, for example, a refractory powder. In this case, since the heat resistance of the obtained inorganic fiber molded object can be improved, the use temperature of the obtained inorganic fiber molded object can be improved.

  Examples of the refractory powder include alumina powder, silica powder, zirconia powder, titania powder, mullite powder, silicon carbide powder, and silicon nitride powder. These can be used alone or in combination of two or more.

  In the composition for inorganic fiber molded body, the content of the refractory powder can be 100 parts by mass or less with respect to 100 parts by mass of the inorganic colloid-containing liquid.

  In this case, it is possible to suppress the decrease in internal hardness and increase in the firing shrinkage rate, and the heat resistance is improved and it becomes easy to obtain an inorganic fiber molded body having a wide use temperature range.

  From the viewpoint of suction moldability, the content of the refractory powder is preferably 25 parts by mass or less, more preferably 10 parts by mass or less, more preferably 5 parts by mass or less, more preferably 100 parts by mass of the inorganic colloid-containing liquid. The amount can be 3 parts by mass or less. Further, from the viewpoint of press moldability, the content of the refractory powder is preferably 80 parts by mass or less, more preferably 70 parts by mass or less, more preferably 60 parts by mass or less with respect to 100 parts by mass of the inorganic colloid-containing liquid. be able to.

  Next, the said inorganic fiber molded object is demonstrated.

  The said inorganic fiber molded object contains an inorganic fiber, an inorganic colloid, and a saponite.

  In the inorganic fiber molded body, the saponite may have an Fe content of 1.3% or less in terms of atomic ratio.

  In this case, as described above, since the effect of suppressing the migration of the inorganic colloid can be increased, an inorganic fiber molded body having a sufficient internal hardness can be obtained.

  In the inorganic fiber molded body, the content of saponite is preferably 0.3 to 5.7 parts by mass with respect to 100 parts by mass of the inorganic fibers.

  In this case, it is possible to obtain an inorganic fiber molded body having an internal hardness suitable for processing such as drilling and more easily suppressing the firing shrinkage rate.

  In this case, the content of saponite is preferably 0.5 parts by mass or more, more preferably 0.7 parts by mass or more, and still more preferably 0 with respect to 100 parts by mass of the inorganic fiber from the viewpoint of improving the internal hardness. .9 parts by mass or more. Further, from the viewpoint of suppressing the firing shrinkage, the saponite content is preferably 5.5 parts by mass or less, more preferably 5.3 parts by mass or less, and further preferably 5 parts by mass with respect to 100 parts by mass of the inorganic fibers. It can be below mass parts.

  In the inorganic fiber molded body, the content of the inorganic colloid is preferably 10 to 100 parts by mass with respect to 100 parts by mass of the inorganic fiber.

  In this case, an inorganic fiber molded body that can easily suppress a decrease in internal hardness can be obtained.

  In this case, the content of the inorganic colloid is preferably 12 parts by mass or more, more preferably 15 parts by mass or more, further preferably 100 parts by mass with respect to 100 parts by mass of the inorganic fiber from the viewpoint of suppressing an increase in the firing shrinkage rate. It can be 18 parts by mass or more. From the viewpoint of lowering the specific gravity and the like, the content of the inorganic colloid is preferably 70 parts by mass or less, more preferably 65 parts by mass or less, and further preferably 60 parts by mass or less with respect to 100 parts by mass of the inorganic fibers. be able to.

  The said inorganic fiber molded object can contain a refractory powder.

  In this case, it is possible to suppress a decrease in internal hardness and an increase in the firing shrinkage rate, and an inorganic fiber molded body having a high fire resistance can be obtained.

  In the inorganic fiber molded body, the content of the refractory powder can be 150 parts by mass or less with respect to 100 parts by mass of the inorganic fiber.

  In this case, an inorganic fiber molded body having high heat resistance is obtained.

  In this case, from the viewpoint of moldability and the like, the content of the refractory powder is preferably 70 parts by mass or less, more preferably 60 parts by mass or less, and even more preferably 50 parts by mass or less with respect to 100 parts by mass of the inorganic fibers. be able to.

  The details of the inorganic colloid, saponite, inorganic fiber, refractory powder and the like in the inorganic fiber molded body can be referred to the description of the above-mentioned inorganic colloid-containing liquid and the composition liquid for inorganic fiber molded body, and the description thereof will be omitted.

  The shape of the inorganic fiber molded body is not particularly limited, and examples thereof include a plate shape (board shape), a block shape, a cylindrical shape such as a cylindrical shape, and a hook shape.

  In addition, each structure mentioned above can be arbitrarily combined as needed, in order to obtain each effect etc.

  The said inorganic colloid containing liquid, the said composition liquid for inorganic fiber molded objects, and the said inorganic fiber molded object are demonstrated using an Example.

<Synthesis of saponite>
Aluminum chloride hexahydrate and iron (III) chloride hexahydrate were respectively prepared in an atomic ratio of about Al: Fe = 10: 0 to 5: 5, and a total of 0.037 mol of aluminum chloride hexahydrate The hydrate and iron (III) chloride hexahydrate were dissolved in 500 ml of water to obtain a solution (1).

  Next, 0.333 mol of magnesium chloride was added to and dissolved in the solution (1) to obtain a solution (2).

  Next, 0.407 mol of sodium metasilicate pentahydrate was dissolved in 500 ml of water, and this was slowly mixed with the solution (2) to obtain a solution (3).

  Next, aqueous ammonia was added to the solution (3) to adjust the pH to 10, followed by stirring for 24 hours. After stirring for 24 hours, the produced precipitate was centrifuged to separate the solution and the solid content.

  Next, after adding water to the obtained solid content and stirring, a washing step A for separating the solution and the solid content was performed by centrifuging again. This washing step A was repeated sufficiently to wash away excess sodium and chlorine, and then the solid content was dried.

  Next, the obtained solid content was finely pulverized and dispersed in 500 ml of water to obtain a dispersion.

  Next, 0.037 mol of sodium hydroxide was dissolved in the obtained dispersion, and hydrothermal reaction was performed at 200 ° C. for 5 hours using an autoclave.

  Next, the solution and solid content were separated by centrifuging the dispersion after the hydrothermal reaction.

  Next, after adding water to the obtained solid content and stirring, washing step B for separating the solution and the solid content was performed by centrifuging again. Excess sodium was washed by repeating this washing step B sufficiently, and then the solid content was dried.

  Subsequently, six types of powdery saponite (1)-(6) were produced by grind | pulverizing the obtained solid content finely. For comparison, a commercially available montmorillonite (Kunimine Kogyo Co., Ltd., “Kunipia F”) was prepared. As representative, saponite (1), (3) and (6) and comparative montmorillonite were subjected to X-ray diffraction using an X-ray diffractometer (RIG2400, “RINT2400”). The result is shown in FIG. As shown in FIG. 1, saponite (1), (3), and (6) were all confirmed to have peaks specific to saponite. In addition, since a broad peak (halo peak) is not observed in the vicinity of 2θ = 20 ° to 30 °, saponite (1), (3) and (6) are composed of a saponite single phase and are amorphous. It was confirmed that there was almost no phase. Moreover, about the saponite (1)-(6), the fluorescent-X-ray analysis was implemented using the fluorescent-X-ray-analysis apparatus (the Rigaku company make, "Rigaku 3270"). As a result, as shown in Table 1, it was confirmed that each saponite had a different Fe content.

  Table 1 summarizes the atomic ratios of synthetic saponite and commercially available montmorillonite.

<Preparation of liquid containing inorganic colloid>
Inorganic colloid-containing liquids of Sample 1 to Sample 19 are obtained by dispersing inorganic colloid and a predetermined saponite in water so that the blending ratio (unit: part by mass) shown in Tables 2 to 5 described later is obtained. It was. As the inorganic colloid, colloidal silica (manufactured by JGC Catalysts Co., Ltd., “Cataloid SI-40”) was used. Moreover, the inorganic colloid containing liquid of the sample 1C and the sample 2C was obtained like the above except not using saponite. Further, an inorganic colloid-containing liquid of Sample 3C was obtained in the same manner as above except that the above montmorillonite was used instead of saponite.

<Preparation of composition liquid for inorganic fiber molding>
Sample 1 to Sample 19, by mixing inorganic fibers and, if necessary, refractory powder, in each inorganic colloid solution so as to have a blending ratio (unit: parts by mass) shown in Tables 2 to 5 described later. Sample liquid compositions for sample 1C to sample 3C were obtained (hereinafter simply referred to as “composition liquid”). Inorganic fibers include refractory ceramic fibers (average fiber diameter 4 μm, average fiber length 500 μm) (manufactured by ITM, “FXL bulk fiber”) or alumina fibers (average fiber diameter 5 μm, average fiber length 500 μm) (stock) “FMX bulk fiber” manufactured by ITM, Inc.) was used. Moreover, alumina powder (average particle diameter d50 = 40 μm) (“A-21” manufactured by Sumitomo Chemical Co., Ltd.) was used as the refractory powder.

<Preparation of inorganic fiber molding>
Each composition liquid was poured into a mold for suction molding having a diameter of 10 cm and laminated by suction molding until the height became 7 cm. Next, a cylindrical suction molded body having a diameter of 10 cm and a height of 7 cm obtained by dehydration by suction molding was roller-pressed to a height of 5 cm in order to make the density uniform and the surface smooth. Next, this suction molded body was dried at 110 ° C. for 24 hours. Next, the dried inorganic fiber molded body is cut to have a rectangular shape with a length of 6.5 cm and a width of 6.5 cm, so that inorganic samples 1 to 9, Samples 11 to 19, and Samples 1C to 3C are inorganic. A fiber molded body was obtained. In addition, since the flow of the composition liquid of sample 10 was lower than that of the composition liquids of sample 1 and samples 7 to 9, no inorganic fiber molded body was produced by suction molding.

  Moreover, the inorganic fiber molded object of the sample which has shapes other than said shape was also produced collectively. Specifically, the composition liquid of Sample 1 was poured into a mold for suction molding having a diameter of 10 cm, and was laminated until the height became 3.5 cm by suction molding. Next, a cylindrical suction molded body having a diameter of 10 cm and a height of 3.5 cm obtained by dehydration by suction molding was roller-pressed to a height of 2.5 cm in order to make the density uniform and the surface smooth. . Next, this suction molded body was dried at 110 ° C. for 24 hours. Next, the inorganic fiber molded body of Sample 20 was obtained by cutting the dried inorganic fiber molded body into a square shape of 6.5 cm in length and 6.5 cm in width.

  In addition, in order to make the density uniform and smooth the surface of a cylindrical suction molded body having an outer diameter of 7.7 cm and an inner diameter of 3.5 cm obtained by dehydration by suction molding using the composition liquid of Sample 1 The pipe was inserted into the inner diameter portion and rolled, and compressed uniformly to an outer diameter of 6.5 cm. Next, this suction molded body was dried at 110 ° C. for 24 hours. Thereby, an inorganic fiber molded body of Sample 21 was obtained.

<Measurement of internal hardness of inorganic fiber molding>
Using an Asker C-type rubber hardness tester, the hardness of the central part on the four side surfaces (cut surfaces) of each inorganic fiber molded body was measured at two locations on each side surface. The average value of the hardness of the 8 places obtained was defined as the internal hardness of the inorganic fiber molded body. When the internal hardness of the inorganic fiber molded body is 30 degrees or more, collapse of the inner wall of the hole due to drilling is easily suppressed.

<Measurement of firing shrinkage of inorganic fiber molding>
Each inorganic fiber molded body was heated at a predetermined maximum temperature for 24 hours. The maximum temperature was 1000 ° C. when refractory ceramic fibers were used as inorganic fibers, and 1300 ° C. when alumina fibers were used. The temperature rising rate was 150 ° C./hour. The length of the four sides of the upper surface of the inorganic fiber molded body before and after firing was measured with a caliper, and the average value of the length of the side before firing and the average value of the length of the side after firing were determined. Then, the firing shrinkage ratio was calculated from the formula 100 × (average value of side length before firing−average value of side length after firing) / (average value of side length before firing). . When the firing shrinkage rate of the inorganic fiber molded body is 3% or less, it can be particularly suitably used for heat insulation.

<Specific gravity of molded inorganic fiber>
Using a caliper and an electronic balance, the specific gravity (bulk density) of each inorganic fiber molded body was measured.

<Ingredient composition in inorganic fiber molding>
The component composition in each inorganic fiber molding was calculated | required as follows using the said fluorescent-X-ray-analysis apparatus. That is, the Mg content, Si content, and Al content in the inorganic fiber molded body are measured. Since Mg is contained only in saponite, the saponite content in the inorganic fiber molded body can be calculated by measuring the amount of Mg in the inorganic fiber molded body. Moreover, by measuring the composition of the used inorganic fiber in advance, the amount of inorganic fiber and the amount of inorganic colloid in the inorganic fiber molded body can be calculated from the ratio of the Al amount and the Si amount. From these results, the amount of saponite and the amount of inorganic colloid with respect to 100 parts by mass of the inorganic fiber were calculated.

  Table 2 to Table 5 summarize the component composition (parts by mass) and physical properties of the prepared inorganic colloid-containing liquid, the composition for inorganic fiber molded body, and the inorganic fiber molded body.

  According to Tables 2 to 5, the following can be understood. In Sample 1C and Sample 2C, the saponite is not contained in the inorganic colloid-containing liquid. Therefore, Sample 1C and Sample 2C were unable to suppress migration of inorganic colloid when saponite dried the molded body, and the internal hardness of the inorganic fiber molded body was low.

  In Sample 3C, although the clay mineral is contained in the inorganic colloid-containing liquid, the clay mineral is montmorillonite. Therefore, in Sample 3C, the viscosity of the composition liquid was not suitable for suction molding unless the amount of inorganic fibers added to the composition liquid was reduced to about 1/11 of that of the other samples. From this result, it can be seen that when montmorillonite is used as the clay mineral, a large amount of montmorillonite is required in order to make the amount of inorganic fibers added to the composition liquid comparable to other samples. It is clear that if the amount of montmorillonite added is large, the firing shrinkage of the inorganic fiber molded body increases due to the increase in the alkali amount. On the other hand, when the amount of inorganic fiber added to the composition liquid is the same as that of other samples, if the amount of montmorillonite added becomes small, it becomes difficult to suppress migration of inorganic colloid, and the inside of the inorganic fiber molded body It is also clear that the hardness decreases.

  On the other hand, according to Samples 1 to 9, an inorganic fiber molded body that includes clay minerals, can suppress a decrease in internal hardness, and can suppress an increase in firing shrinkage rate can be obtained. I understand that. This is because by using saponite as the clay mineral contained in the inorganic colloid-containing liquid, migration of the inorganic colloid to the surface of the molded body during drying was suppressed with a small amount of clay mineral.

  Moreover, when Sample 1 to Sample 6 are compared, in the inorganic colloid-containing liquid, when the Fe content of the saponite is 1.3% or less by atomic ratio, an inorganic fiber molded body having sufficient internal hardness can be obtained. I understand that. This is because the migration suppression effect of the inorganic colloid is increased when the Fe content of the saponite is 1.3% or less in terms of atomic ratio.

  Moreover, when Sample 1 and Sample 7 to Sample 9 are compared, it can be seen that as the content of saponite in the inorganic colloid-containing liquid increases, the internal hardness of the resulting inorganic fiber molded body increases. In Sample 1, Sample 7 to Sample 9, since the saponite content in the inorganic colloid-containing liquid was 2 parts by mass or less with respect to 100 parts by mass of water, the fluidity of the composition liquid was high, and the moldability by suction molding was high. It was easy to secure.

  Here, according to previous experiments by the present inventors, when the content of saponite in the inorganic colloid-containing liquid is 3 parts by mass or less with respect to 100 parts by mass of water, the composition liquid is allowed to stand still. A tendency to become sol has been confirmed. However, when the content of saponite in the inorganic colloid-containing liquid exceeds 2 parts by mass with respect to 100 parts by mass of water, the fluidity of the composition liquid tends to deteriorate. Therefore, when molding an inorganic fiber molded body by suction molding the composition liquid, it can be said that the content of saponite in the inorganic colloid-containing liquid is desirably 2 parts by mass or less with respect to 100 parts by mass of water. Further, when the content of saponite in the inorganic colloid-containing liquid is more than 3 parts by mass to 4 parts by mass or less with respect to 100 parts by mass of water, the composition liquid becomes a gel in a stationary state, It has been confirmed that the composition liquid tends to be in a sol state. Furthermore, when the content of saponite in the inorganic colloid-containing liquid is more than 4 parts by mass, it has been confirmed that the composition liquid tends to be gel-like even in a stirred state. When molding an inorganic fiber molded body by press molding the composition liquid, there is no need to worry too much about the increase in viscosity of the composition liquid due to the increase in saponite, but it becomes difficult to mix inorganic fibers and the uniformity of the molded body May decrease. Therefore, when an inorganic fiber molded body is molded by press molding the composition liquid, it can be said that the content of saponite in the inorganic colloid-containing liquid is preferably 4 parts by mass or less with respect to 100 parts by mass of water. As can be seen from the comparison between Sample 1C and Sample 7, the content of saponite in the inorganic colloid-containing liquid is set to 0. It can be said that it is preferable to use 1 part by mass or more. To summarize the above, in the inorganic colloid-containing liquid, when the saponite content is 0.1 to 4 parts by mass with respect to 100 parts by mass of water, ensuring the moldability of the composition liquid, the inside of the inorganic fiber molded body It can be said that the hardness can be ensured.

  Moreover, when the relationship between the content of saponite in the inorganic fiber molded body and the internal hardness is obtained using the least square method (linear) for Sample 1C, Sample 1, and Sample 7 to Sample 9, in the inorganic fiber molded body When the saponite content is 0.3 parts by mass or more with respect to 100 parts by mass of the inorganic fibers, the internal hardness is 30 degrees or more. Therefore, it can be said that it becomes easy to obtain an inorganic fiber molded body having an internal hardness suitable for drilling by setting the content of saponite in the inorganic fiber molded body to 0.3 parts by mass or more with respect to 100 parts by mass of the inorganic fibers. .

  Similarly, when the relationship between the content of saponite in the inorganic fiber molded body and the firing shrinkage ratio is obtained for Sample 1C, Sample 1, Sample 7 to Sample 9 using the least square method (linear), inorganic fiber molding When the content of saponite in the body is 5.7 parts by mass or less with respect to 100 parts by mass of the inorganic fibers, the firing shrinkage rate is 3% or less. Therefore, it can be said that it becomes easy to obtain an inorganic fiber molded body in which the firing shrinkage rate is more easily suppressed by setting the content of saponite in the inorganic fiber molded body to 5.7 parts by mass or less with respect to 100 parts by mass of the inorganic fibers.

  In addition, when Sample 1 and Sample 11 are compared, the inorganic colloid content in the inorganic fiber molded body is set to 100 parts by mass or less with respect to 100 parts by mass of the inorganic fibers, thereby easily suppressing an increase in the firing shrinkage rate. It can be said that it becomes easy to obtain an inorganic fiber molded body. In addition, although not described in the table, when the content of the inorganic colloid in the inorganic fiber molded body exceeds 100 parts by mass with respect to 100 parts by mass of the inorganic fiber, the firing shrinkage rate rapidly increased.

  Moreover, when the amount of the inorganic fiber with respect to the composition liquid was less than that of Sample 1 to Sample 15 for Sample 16 to Sample 19, a dense molded body having a higher specific gravity could be obtained. Comparing sample 1 and sample 16, it can be seen that the internal hardness is high even if the amount of the inorganic colloid relative to the inorganic fiber is small. Furthermore, when the amount of inorganic colloid in the inorganic colloid-containing liquid is reduced, the amount of saponite is increased, so that the internal strength is increased to 30 degrees or more with a smaller content of inorganic colloid compared to Sample 1 to Sample 15 or Sample 16. I was able to. When the relationship between the content of the inorganic colloid in the inorganic fiber molded body and the internal hardness is obtained for the samples 16 to 19 using the least square method (linear), the content of the inorganic colloid in the inorganic fiber molded body is as follows. And the internal hardness of an inorganic fiber molded object will be 30 degree | times or more as it is 10 mass parts or more with respect to 100 mass parts of inorganic fibers. Therefore, it can be said that it becomes easy to obtain an inorganic fiber molded body in which a decrease in internal hardness is easily suppressed by setting the content of the inorganic colloid in the inorganic fiber molded body to 10 parts by mass or more with respect to 100 parts by mass of the inorganic fiber.

  Further, comparing sample 1 and sample 11, when the content of the inorganic colloid in the inorganic colloid-containing liquid is 20 parts by mass or less with respect to 100 parts by mass of water, the composition liquid is reduced by suction molding. It can also be seen that it is easy to obtain an inorganic fiber molded body having a high specific hardness at a specific gravity. When the content of the inorganic colloid in the inorganic colloid-containing liquid is more than 20 parts by mass with respect to 100 parts by mass of water, an inorganic fiber molded body having a high internal hardness is obtained by press molding the composition liquid. Can be obtained. However, according to previous experiments by the present inventors, it has been confirmed that when the content of the inorganic colloid in the inorganic colloid-containing liquid exceeds 67 parts by mass, the stability of the inorganic colloid decreases. Therefore, it can be said that the content of the inorganic colloid in the inorganic colloid-containing liquid is desirably 67 parts by mass or less from the viewpoint of maintaining the stability of the inorganic colloid and ensuring the curability of the inorganic fiber molded body. Further, from the viewpoint of ensuring that the hardness of the inorganic fiber molded body is 30 degrees or more, the content and the internal hardness of the inorganic colloid in the inorganic colloid-containing liquid are used for Sample 16 to Sample 19 using the least square method (linear). The content of inorganic colloid in the inorganic colloid-containing liquid is preferably 4 parts by mass or more with respect to 100 parts by mass of water. Summarizing the above, in the inorganic colloid-containing liquid, when the content of the inorganic colloid is 4 to 67 parts by mass with respect to 100 parts by mass of water, ensuring the moldability of the composition liquid and the internal hardness of the inorganic fiber molded body It can be said that ensuring of this can be ensured.

  In addition, when Sample 1 and Sample 12 are compared, an inorganic fiber molded body that can suppress a decrease in internal hardness and suppress an increase in firing shrinkage rate regardless of which inorganic fiber is used. It can be seen that

  In addition, when Sample 1 and Sample 13 to Sample 15 are compared, when the refractory powder is added to the composition liquid and the refractory powder is contained in the inorganic fiber molded body, the fire resistance of the resulting inorganic fiber molded body is improved by the refractory powder. It can be said that it becomes easy to make it. However, it can be said that the content of the refractory powder is preferably 150 parts by mass or less with respect to 100 parts by mass of the inorganic fiber from the viewpoint of avoiding deterioration of moldability.

  Similarly, the results of the suppression of the migration of the inorganic colloids were also obtained for the sample 20 and the sample 21 of the sample 21 having different shapes and thicknesses from the sample 1 to the sample 9 and the sample 11 to the sample 15. In addition, it was possible to suppress a decrease in internal hardness and to suppress an increase in the firing shrinkage rate.

  As mentioned above, although the Example of this invention was described in detail, this invention is not limited to the said Example, A various change is possible within the range which does not impair the meaning of this invention. For example, in the examples, the case where the inorganic colloid-containing liquid is used for the application of the inorganic fiber molded body composition liquid and the inorganic fiber molded body is described. However, the inorganic colloid-containing liquid is not limited to these applications. It can be used for other applications where migration of inorganic colloids is a problem.

Claims (12)

  An inorganic colloid-containing liquid containing water, an inorganic colloid, and saponite.   The said saponite is an inorganic colloid containing liquid of Claim 1 whose Fe content is 1.3% or less in an atomic ratio.   3. The inorganic colloid-containing liquid according to claim 1, wherein the content of the saponite is 0.1 to 4 parts by mass with respect to 100 parts by mass of water.   The inorganic colloid-containing liquid according to any one of claims 1 to 3, wherein the content of the inorganic colloid is 4 to 67 parts by mass with respect to 100 parts by mass of water.   The inorganic colloid-containing liquid according to any one of claims 1 to 4, which does not contain an organic substance or has an organic substance content of 1 part by mass or less with respect to 100 parts by mass of water.   The composition liquid for inorganic fiber moldings containing the inorganic colloid containing liquid of any one of Claims 1-5, and inorganic fiber.   Content of the said inorganic fiber is a composition liquid for inorganic fiber moldings of Claim 6 which is 25 mass parts or less with respect to 100 mass parts of said inorganic colloid containing liquids.   The composition for an inorganic fiber molded body according to claim 6, wherein the content of the inorganic fiber is more than 25 parts by mass to 300 parts by mass with respect to 100 parts by mass of the inorganic colloid-containing liquid.   An inorganic fiber molded body containing inorganic fiber, inorganic colloid, and saponite.   The said saponite is an inorganic fiber molded object of Claim 9 whose Fe content is 1.3% or less by an atomic ratio.   The inorganic fiber molded body according to claim 9 or 10, wherein the content of the saponite is 0.3 to 5.7 parts by mass with respect to 100 parts by mass of the inorganic fibers.   Content of the said inorganic colloid is an inorganic fiber molded object of any one of Claims 9-11 which is 10-100 mass parts with respect to 100 mass parts of said inorganic fibers.

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