JPH07247179A - Ceramic structure material, its production and production of ceramic sheet - Google Patents

Abstract

PURPOSE:To obtain a ceramic structural material light-weight, excellent in strength, impact resistance, water resistance, heat insulation and refractoriness and including pores by molding a ceramic sheet mainly containing an organic fiber and a ceramic material into a ceramic sheet-shaped formed article including many pores and subsequently calcining it. CONSTITUTION:This ceramic structural material is produced in the following processes A and B. (A) Ceramic sheets consisting of a formed material or unformed material mainly containing an organic fiber and a ceramic material or both of the formed and unformed material is molded into a formed article including many pores. (B) The formed article is calcined to obtain a ceramic structure material including many pores. In the process A, a ceramic sheet- shaped formed article having specific pores is produced by layering formed ceramic sheets including pores. The ceramic sheet is produced by a press molding method, a doctor-blade method or a rolling method.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a ceramic structure containing a large number of voids containing organic fibers and ceramics as main components, for example, a plate-shaped ceramic structure. It is useful as a plate or other three-dimensional structure or structural material, and is particularly suitable for a large-scale building material. It also relates to a method of manufacturing a ceramic sheet that also serves as a material for the structure.

[0002]

2. Description of the Related Art Conventionally, a radiator and a catalyst carrier have been used as the porous body containing ceramic as a main component. These were mainly made by extrusion or injection molding. However, these molding methods require a mold having a complicated shape, and a thin cell partition wall has a high risk of crack cracking during demolding or drying. Moreover, it is difficult to manufacture large-sized products, and it is almost impossible to manufacture large-diameter products or flat-plate large-area products. In addition, when there was a change in the cell diameter, the mold was replaced.

There is also known a method in which a ceramic block or sheet after firing is carved out by cutting or grinding to obtain a predetermined shape (structure or plate-shaped body having pattern holes). Since it is a brittle material having a high hardness, the grinding time was enormous, and the cutting or grinding tool was greatly worn.

Therefore, as an application of ceramics technology, a plastic sheet and a binder are added only to ceramic powder, and the mixture is poured onto a film substrate to form a green sheet-like material by a doctor blade method or a calendar method, which is then processed and formed. Then, there was a method of firing to obtain a structure. Japanese Patent Laid-Open No. 64-11808
For the issue, green sheets are corrugated and laminated,
A fired structure and method of making the same is described. However, with this method, there is a limit in the thickness of the production of a thin sheet, and the binding force between the ceramic particles is weak and there is a problem in the shape retention force.

Also in the calendering method in which a ceramic-filled film is squeezed and rolled into a sheet, the bonding force between the ceramic particles is weak and there is a problem in the shape retention.

By the way, heat insulating materials, wall materials, ceiling materials, fence materials,
For building materials such as partition walls, inorganic concrete,
Gypsum board, organic vinyl chloride resin, polyurethane resin, etc. are used. However, inorganic materials are inferior in heat insulation and water resistance, and when they are porous, they have excellent heat insulation but have low strength, while organic materials have the drawbacks of low fire resistance and low independence. Further, in order to manufacture a structural material having a curved surface, it is necessary to change the structure from a mold (template, mold), and the strength is further deteriorated at the curved portion.

[0007]

Ceramics are used in various fields as products having excellent structure or functional characteristics, and in order to be used as a structure, weight reduction and size increase are particularly important issues. It was Among them, the weight reduction can be achieved by making the material porous, but the strength is deteriorated. On the other hand, if the size is increased, there is a serious obstacle to its practical use due to an extreme decrease in yield due to firing strain. In addition, there was no ceramic sheet suitable for obtaining the above structure and having excellent flexibility and shape retention.

As described above, the conventional manufacturing method of the ceramic structure (plate-shaped body) has a fundamental limit, but the conventional manufacturing method described above has the following problems.

That is, firstly, the use of the green sheet and the film sheet in which the ceramic powder, which is an application of the ceramics technology, is developed into a sheet shape, the sheet thickness cannot be made very thin, and flexibility and Poor shape retention,
Moreover, the process was complicated and expensive. Further, since an expensive resin or an organic solvent is used as a binder for the ceramic powder, the process is complicated and the cost is high, and the industrial hygiene is poor.

Secondly, since the ceramic sheet containing ceramic fibers as a main component is made of ceramic fibers as a raw material, it is expensive and requires various additives to complicate the process.

The applications of the first and second ceramic structures are limited to catalyst carriers and heat exchangers (radiators).

Thirdly, the use of ceramic paper containing organic fibers and ceramic particles as main components was limited to very small ones such as arts and crafts and daily necessities, or very thin ones.

Fourthly, in conventional structures (particularly plate-like members), particularly construction materials (wall materials, pillar materials, etc.), impact resistance, light weight, strength, water resistance, heat insulation, fire resistance, etc. There was no material that had the essential mass productivity. And especially,
It was not possible to obtain a complicated shape having a curved surface.

Fifth, in order to obtain a predetermined shape (structure or sheet pattern) by cutting out the sintered ceramic block or sheet by grinding or the like, since the ceramic is a brittle material having high hardness, it is ground. The time was enormous, and the cutting or grinding tools were worn out.

The basic object of the present invention is to provide a novel ceramic structure having a structure including a void, which is lightweight, has strength, and further has impact resistance, water resistance, heat insulation and fire resistance, and a method for manufacturing the same. Especially. A second object of the present invention is to provide a ceramic sheet which is also a raw material of this structure and which is excellent in flexibility and shape-retaining power, which can be a porous structure by itself. It is a specific object of the present invention to provide a novel manufacturing method that enables mass production of such ceramic sheets and structures. From another point of view, the present invention is not limited to the size or the shape, and in particular, it is possible to produce a large sheet, a plate-shaped body or a structure, and to produce an excellent building wall material. It will be a specific subject. It is a further specific object to provide a method for manufacturing a ceramic sheet and a structure in which the voids can have a particularly small diameter and the size and shape of the voids can be freely controlled. Another object of the present invention is to provide a method for manufacturing such a ceramic sheet and a structure, which can be applied to a case where the internal constituent layers are extremely thin to a considerable thickness.

Another object of the present invention is to manufacture a structure which can be highly utilized as an internal space formed by a large number of voids as a heat storage body, a piping space, etc.

Another object of the present invention is to provide a method for manufacturing a ceramic sheet which has a high shape retention force even before sintering and is easy to mold and process. Another object is to provide a method for manufacturing a ceramic sheet that is simple and safe in the manufacturing process. Another object is to obtain various fine void shapes (diameter, opening shape, etc.) after sintering by controlling the raw material composition of the ceramic sheet. It should be noted that even with this ceramic sheet alone, the form of the voids can be changed by adjusting the sheet raw material, and it can be said that the sheet itself is a porous body (structure) having a large number of voids.

[0018]

The basic object of the present invention is to:
In particular, it is composed of the following first and second viewpoints. A first aspect of the present invention (first means) is to form a molded or unformed ceramic sheet containing organic fibers and a ceramic raw material as main components, or a ceramic sheet of both of them into a ceramic sheet molded article containing a large number of voids. A method of manufacturing a ceramic structure, comprising: a step of baking the molded body to form a ceramic structure containing a large number of voids (claim 1).

The molded ceramic sheet is a sheet having a predetermined void (for example, a tubular, spherical, or other deformed shape), an uneven shape due to an unequal change in cross section (a shape like an embossed product), It is a sheet that has been shaped such as corrugated on the plate surface. On the other hand, the unformed ceramic sheet is a flat or flat sheet paper that is generally found other than the above. However, a ceramic sheet having die-cut or cut pattern holes is treated as a formed sheet paper in the present invention. These molded and unmolded ceramic sheets are molded into a molded article including at least molded sheet paper.

As a method for molding a ceramic sheet molded article, a single ceramic sheet or a plurality of ceramic sheets are bent, bonded (adhesive may be used), aggregated, polymerized, so as to include a large number of voids. Stacking, winding, mating, joining,
A pressure contact method, a pressure bonding method, or some combination thereof is applicable.

A second aspect of the present invention is (23rd means),
The method for producing a ceramic sheet is a method for producing a ceramic sheet containing an organic fiber by a pressing method (claim 23). By this pressing method, in addition to the sheet having a flat surface, the sheet is punched and has voids,
Alternatively, a sheet having irregularities can be obtained.

A third aspect of the present invention is (25th means),
The method for producing a ceramic sheet is a method for producing a ceramic sheet containing an organic fiber by a doctor blade method (claim 25).

A fourth aspect of the present invention is (26th means),
The method for producing a ceramic sheet is a method for producing a ceramic sheet containing organic fibers by rolling (calendar method) (claim 26). The fifth aspect of the present invention is
It is a ceramic structure obtained from the first to fourth aspects (claims 29 and 30).

[0024]

According to a second aspect of the present invention, in the first aspect, the shaped ceramic sheet has voids, and the shaped ceramic sheets are polymerized in the shaping step to have predetermined voids. A method for manufacturing a ceramic structure, wherein a ceramic sheet molded body is molded (claim 2).

In a third aspect of the present invention, in the first aspect, the forming step includes a step of processing a ceramic sheet into a substantially corrugated plate shape, and a plurality of layers each including at least one substantially corrugated plate-shaped ceramic sheet. The method for producing a ceramic structure according to any one of the first to second means, characterized in that the method includes the step of superposing the layers on each other (claim 3).

According to a fourth aspect of the present invention, in the first aspect, the forming step includes a step of processing a ceramic sheet into an uneven shape by embossing, and a plurality of layers including at least one uneven ceramic sheet. The method for producing a ceramic structure according to any one of the first to third means, characterized in that the method includes the step of superimposing on the ceramic structure (claim 4).

In a fifth aspect of the present invention, in the first aspect, in the forming step, at least a tubular ceramic sheet is used as the formed ceramic sheet, and a ceramic sheet formed article including a plurality of tubular ceramic sheets is formed. The method for manufacturing a ceramic structure according to any one of the first to fourth means is characterized in that (claim 5). It can be formed into a plate, a column, or a block, and tubular ceramic sheets can be arranged in parallel or crossed. The cross section of the tubular ceramic sheet can be a circle, a triangle, a polygon such as a quadrangle, or a wound body of a layer having an uneven surface. For example, when the cross section is a quadrangle, it becomes a prismatic shape as a whole.

According to a sixth aspect of the present invention, in the first aspect, the forming step includes a step of processing a ceramic sheet into a tubular shape, and a plurality of tubular ceramic sheets having a flat plate shape or unevenness. The method for manufacturing a ceramic structure according to any one of the first to fifth means, characterized in that the method includes a step of integrally joining the ceramic sheets with or without interposing the ceramic sheets (Claim 6). The tubular formation can be performed by a known method, for example, spiral winding from a strip (roll) or extrusion molding.

According to a seventh aspect of the present invention, in the first aspect, the forming step includes a step of cutting at least one ceramic sheet into a predetermined shape and at least one piece of paper cut into the predetermined shape. The method for producing a ceramic structure according to any one of the first to sixth means, characterized in that the ceramic structure is bonded to a single ceramic sheet to form a three-dimensional structure (claim 7).

Here, the predetermined shape means that one that can form a three-dimensional structure containing voids by rolling or polymerizing, such as a string-like shape, a band-like shape, or a three-dimensional structure such as a tubular shape, a cylindrical shape, a ring shape, a semi-ring shape. The shape corresponds to the shape obtained by cutting the part having "." Approximately, the product itself or a processed product may be one that can form the above three-dimensional structure.

The eighth means of the present invention is the ceramic structure according to the seventh means, characterized in that, in the first aspect, the ceramic sheet has a porous or predetermined pore pattern by the cutting. (Claim 8).

A ninth means of the present invention is the seventh or eighth means characterized in that, in the first aspect, a molded article is formed including a cut product obtained by cutting the tubular ceramic sheet. The method for manufacturing a ceramic structure according to (9).

A tenth means of the present invention is, in the first aspect, characterized in that a plurality of the cut products are molded into a molded object via at least one ceramic sheet. A method of manufacturing a ceramic structure (claim 10).

An eleventh means of the present invention is, in the above first aspect, including at least a porous molded ceramic sheet obtained by folding back a ceramic sheet into two or more layers, cutting it, and then partially expanding it. It is a method for manufacturing a ceramic structure according to the tenth feature (claim 11).

A twelfth means of the present invention is, in the first aspect, formed as at least a part of the formed ceramic sheet by making a large number of cuts in a slab and then extending it in at least one direction. The method for manufacturing a ceramic structure according to any one of the first to eleventh means, wherein a lath sheet is used.

A thirteenth means of the present invention is, in the first aspect, that in the molding step, the ceramic sheet molded objects are molded so as to include voids that are independent of each other and are continuously arranged. It is a method for manufacturing a ceramic structure according to any one of the first to twelfth features.

A fourteenth means of the present invention is, in the first aspect, characterized in that a flat plate-shaped ceramic sheet is used as a mounting material, and the production of a ceramic structure according to any one of the first to thirteenth means. Method (claim 14).

[0038] A fifteenth means of the present invention is, in the first aspect, characterized by including at least one flat or substantially flat ceramic sheet as an intermediate layer.
The method for producing a ceramic structure according to any one of 14 means (claim 15). The term "substantially flat plate-like" refers to a case in which there are fine irregularities and waviness, but the layer is transformed into a flat plate as a whole (as a guide, the displacement in the thickness direction is 1/5 to 1/10 of the irregularity pitch). The following).

A sixteenth means of the present invention is, in the first aspect, characterized in that the structure is a plate-like body, and the ceramic structure according to any one of the first to fifteenth means is manufactured. Method (claim 16).

A seventeenth means of the present invention is the production of the ceramic structure according to any one of the first to sixteenth means, characterized in that, in the first aspect, the plate-like body is a building material. Method (claim 17).

An eighteenth means of the present invention is, in the first aspect, characterized in that the organic fibers are cellulose fibers or synthetic or artificial fibers.
The method for producing a ceramic structure according to any one of the above-mentioned means (claim 18).

[0042] A nineteenth means of the present invention is, in the first aspect, characterized in that the ceramic raw material has a porcelain composition containing alumina as a component. A method for manufacturing a ceramic structure (claim 19). The ceramic raw material may have a porcelain or porcelain composition containing alumina fibers, ceramic fibers, artificial or natural fibers such as wollastonite, and whiskers. In this case, a so-called fiber-reinforced ceramic structure is obtained.

A twentieth means of the present invention is, in the first aspect, characterized in that an organic or inorganic binder or a mixture thereof is used as an adhesive in the molding step. The method for producing a ceramic structure according to any one of the above-mentioned means (claim 20).

The twenty-first means of the present invention is, in the first aspect, characterized in that the ceramic structure is glazed after firing or before firing. A method for manufacturing a ceramic structure (claim 21). Firing can be controlled and controlled according to the desired degree of sintering, ultimate density, material of the predetermined ceramic raw material, sintering characteristics, and the like. The material of each layer itself may be a fine porous material to a dense material, or a combination thereof.

The twenty-second means of the present invention comprises a coating step of coating at least a part of the ceramic sheet layer of the ceramic sheet molded article with mud of a ceramic material. The method for producing a ceramic structure according to item (22). This coating includes known mud coating methods such as dipping, spraying and coating.

A twenty-fourth means of the present invention is, in the second aspect, characterized in that embossing is carried out during the pressing to obtain an uneven shaped ceramic sheet.
It is a method for manufacturing a ceramic sheet according to the third aspect (claim 23). In addition, the uneven shape includes a wave shape, an uneven pattern uneven shape, and the like.

A twenty-seventh means of the present invention is, in the third aspect, characterized in that the sheet-like material is made of organic paper, cloth or non-woven fabric, and the ceramic sheet according to the twenty-sixth means. (Claim 27).

[0048]

OPERATION Ceramics are used in various fields as products having excellent structural or functional characteristics, but in order to be used as a structural body, weight reduction and size increase have been particularly important issues. Among them, the weight reduction can be achieved by making the material porous, but the strength is deteriorated. On the other hand, if the size is increased, there is a serious obstacle to its practical use due to an extreme decrease in yield due to firing strain. Further, since ceramic is hard and brittle, it is difficult to process it into a complicated shape, and it takes time in cutting or grinding and wear of the cutting or grinding tool is also great.

So-called porcelain paper has been developed as a material using a ceramic sheet as a material, but it is still in the range of ceramics or arts and crafts.

According to the present invention, an organic fiber and a ceramic powder, which are highly flexible and self-supporting and inexpensive, are used as raw materials to cut, adhere, and cut a ceramic sheet produced by the production method or papermaking technique of the present invention. A ceramic molded object (structure, fired paper type, that is, unfired molded object) having a large number of voids can be freely molded by a simple process such as corrugation, and the molded object is fired to a predetermined size. Obtaining a ceramic structure having a shape and containing a predetermined void. The ceramic structure can have properties such as sufficient light weight, strength (further, impact resistance), heat insulation, fire resistance, and water resistance. Further, according to the present invention, a three-dimensional structure having a complicated internal structure, particularly a large-sized structure having independent voids and continuous voids can be easily obtained. Therefore, it is possible to provide a material that can be used as an outer wall material (for example, a length of 1 m or more) or the like in which a ceramic structure has not been used until now. The thickness can be obtained within a practically required range. For example, a huge material having a width of 120 cm × 450 cm can be obtained, and an arbitrary thickness can be manufactured.

One of the methods is a paper (organic fiber) mixed with a ceramic powder (kneaded clay), which is formed or not formed,
Alternatively, the method is characterized by including a step of forming both of the ceramic sheets into a ceramic sheet formed body and a sintering step of sintering the formed ceramic formed body. By adjusting these raw materials, structures having various pore morphologies (cells, porosity) can be obtained. That is,
In the fibrous material, the cell diameter on the micron order can be controlled during sintering by adjusting the fiber type, the fiber length, and the fiber diameter. On the other hand, in the ceramic raw material, the cell diameter can be controlled in the angstrom order by adjusting the components, the particle size and the like. Also, the cell diameter can be controlled in the angstrom order by lowering the sintering density of the ceramic material by lowering the sintering conditions such as the sintering temperature. Also, the cell morphology can be adjusted to some extent by the size of the molecule of the plasticizer (sugar alcohol, etc.).

Further, particularly for the purpose of strengthening and protecting the structure, a coating step of coating (preferably dipping) the ceramic material layer on at least a part of the ceramic sheet layer of the ceramic sheet molded article. Can be included.

During the coating step, the ceramic molded body is coated in a slurry of ceramic material (which forms a particularly dense and high-strength sintered ceramic coating layer) so that each ceramic sheet is more dense. It can be reinforced with a ceramic coating, resulting in a more reinforced ceramic structure overall.

Now, the method for producing the ceramic sheet of the present invention and the sheet used for producing the ceramic structure will be described. Organic fiber raw material is cellulose fiber,
Also, any fiber that is a raw material for ordinary paper, such as natural vegetable fiber, may be used, and cellulose fiber is generally preferable. In addition, acrylic, artificial fiber, cotton cloth and the like can be used. Cellulose fibers burn out without producing harmful gases during firing. Therefore, in addition to bast pulp such as Manila hemp and jute,
Since recycled paper such as newspapers and magazines and rag pulp such as rags can also be used, the recycling effect can be exhibited. As the ceramic raw material, kneaded clay (for example, alumina, silica stone, feldspar, and clay) which is a raw material for pottery and porcelain can be used. In particular, if alumina is added, the strength will increase. Further, the strength, particularly the toughness, can be enhanced by adding natural or synthetic ceramic fibers, whiskers and the like. In addition, so-called new ceramic materials (cordierite, alumina,
Oxides of zirconia, various nitrides such as boron nitride, carbides such as silicon carbide, borides, and other complex compounds or mixtures thereof) may be used.

In the method for producing a ceramic sheet of the present invention, since the organic fiber is always contained in the raw material and acts as a binder, it has a strong shape-retaining force, and is formed into a sheet or paper-like molded object before sintering. However, the ceramic powder does not come off. Therefore, it is possible to use no harmful organic solvent as a binder or to use a very small amount. Finally, by firing, the organic fibers disappear to form predetermined pores. Then, the pore morphology can be adjusted as described above. The fibers may be either long fibers or short fibers, or may be a single fiber, a composite fiber, or a twisted fiber, and the morphology of the pores can be adjusted by the state or the aspect ratio (major axis ratio) of the fibers.

The first ceramic sheet manufacturing method of the present invention is by press molding. The ceramic powder and the organic fiber are mixed and compressed to obtain a ceramic sheet. Both dry and wet pressing are possible, and when the mixture is a mud containing water, dehydration is carried out by pressing. This method is particularly suitable for obtaining a thick sheet of cm order. Here, as the organic fibers, for example, flat paper or cloth (or pieces thereof)
May be included. The ceramic component is impregnated and adhered to the paper (cloth) by press compression.

The second ceramic sheet is manufactured by the doctor blade method. Since the raw material contains organic fibers, it has a high shape-retaining power, and it is easy to obtain a relatively thin sheet.

The third ceramic sheet manufacturing method is a roll rolling method. In particular, it is suitable for continuous mass production. The sheet-like material to be the core or mount is a paper made of organic fiber,
In the case of cloth or the like, the mixture containing a ceramic raw material (powder, mud, gel, etc.) as a main component may not contain organic fibers. On the other hand, when the sheet-like material is a chemical film containing no organic fibers such as polyethylene and polyester, it is preferable that the mixture contains organic fibers.

In the above three sheet manufacturing methods, the organic fibers serve as a strong binder. However, when the amount of fibers is less than that of ceramics, a binder (ethyl cellulose, abietic acid resin) is used. Etc.), a plasticizer (abietic acid derivative, polyalkylene glycol, etc.), a deflocculant (glycerin, octadecylamine, etc.), and a solvent (toluene, methyl ethyl ketone, etc.) may be used.

The ceramic sheet used in the method for producing a structure of the present invention can also be obtained by papermaking. The method of papermaking may be any known method and is not particularly limited, but is usually a wet papermaking method or a semi-wet papermaking method.

The wet papermaking method can be carried out using a round-net paper machine, a Fourdrinier paper machine, or the like. According to this method, a ceramic sheet having both flexibility and strength can be obtained. The paper thickness is 0.1mm, and the thick one is 5
Paper of cm or more is obtained. Usually, the paper thickness is about 2 to 3 mm. Further, thick paper can be obtained by stacking a plurality of papers, and since it has many empty portions, it is lighter than a single paper of the same thickness. As a size of such a ceramic sheet, for example, a huge sheet of 1500 mm × 4500 mm and a thickness of 0.1 mm to 5 cm can be freely adjusted. This size depends only on the practical size of the equipment of the papermaking and baking device, and there is no theoretical limit.

In the present invention, it is sufficient to use a ceramic powder type raw material, but it is also possible to utilize components of other types as additive materials, and any of them can be the ceramic sheet used in the present invention. Is not necessary for obtaining a predetermined strength, and cellulose fibers can be used, so that it is preferable from the viewpoint of manufacturing process and cost reduction. The inclusion of ceramic fibers has the advantage of improving toughness.

In the step of forming the ceramic sheet formed article of the present invention, the ceramic sheet is processed and formed into a shape similar to a desired structure. As a forming method, as an example, a corrugated plate which is a manufacturing process of a corrugated cardboard core is used to process a ceramic sheet into a corrugated plate having a continuous pattern in which semicircles are alternately inverted and continuous (sine curve shape). . A ceramic sheet is bonded to one side or both sides using this as a core. As the adhesive, it is preferable to use a slurry containing a small amount of sugar alcohol in the friend soil (kneaded clay containing the same ceramic raw material as the object to be adhered), but since the ceramic sheet has both organic and inorganic materials, it is possible to use organic or inorganic adhesives. Both agents can be used. As the inorganic adhesive, an inorganic binder such as ceramic slurry of the same kind or different kinds, sodium silicate or the like can be used, and an organic / inorganic mixture can also be used. Thus, a ceramic sheet structure having a structure containing voids can be easily obtained without performing a grinding process.

The space structure can also be obtained by pressing or embossing the ceramic sheet. For example, if one or a plurality of ceramic sheets are die-cut or molded into a shape having a desired unevenness by press working,
A structure element containing a large number of voids is obtained. The press or embossing element may or may not be porous and may have a given irregularity (particularly a convexity). When this element is used as a core or laminated in multiple layers, a structure containing a large number of voids is obtained. The same thing can be done by using a lath sheet made of a ceramic sheet (having a large number of cuts and extending at least one side to form a mesh).

If the ceramic sheet is formed into a tubular shape and cut into slices or parallel to the axis, these are arranged on the ceramic sheet, and the ceramic sheet is stuck on the ceramic sheet, a structure having a large number of voids is formed. can get. The tubular ceramic sheets may be bundled in a predetermined outer shape, the ceramic sheet may be covered around the tubular ceramic sheets, or this may be repeated several times. Further, by slicing the thus bundled pieces into a predetermined length (thickness), it is possible to obtain a plate-like body having a mesh or honeycomb cross-section structure having many voids.

Also, various complicated three-dimensional shapes and structures can be easily realized by cutting and pasting the template. If necessary, a flat ceramic sheet is used as a cover material. A flat ceramic sheet may be interposed between the cores.

Here, when strengthening / protection of the structure is particularly required, a component which is the same as or close to the raw material is again added to the ceramic sheet layer (at least a part or part of the layer) of the ceramic sheet molded body. When the clay containing kneaded clay is adhered and fired, each ceramic sheet is reinforced with a denser ceramic coating, and a ceramic structure that is further reinforced as a whole is formed. The surface to be attached may be the entire paper molding (entire surface) or only the surface forming the surface layer. In both cases, a strong protective / reinforcing film is formed after firing to enhance strength and environmental resistance. Such adhesion can be applied to the ceramic sheet obtained by the method for producing a sheet of the present invention, and the same effect can be expected.

Step 2 is a firing step of firing the molded body in a furnace. Finally, when the ceramic sheet structure of the above process is fired, the paper component is sintered in a form sandwiched between the dense coat layers on both sides to maintain the original shape,
A high strength ceramic structure is obtained.

The firing process may be performed once, or may be divided into a bisquedging process or a tightening process (or both) and a main firing process. It is possible to apply a glaze to a compacted (or unglazed) ceramic sheet molded article to give it an exterior appearance and color to give it a beautiful appearance, and to enhance its strength and water resistance after firing. The dense layer and / or the glaze layer can be selected such that a higher compressive stress is exerted than the internal ceramic layer and the fiber layer, and it becomes a reinforcing layer (or protective layer) due to the difference in the cracking ratio.

The molded body is fired in a predetermined atmosphere. The temperature varies depending on the raw material. When the high-strength porcelain raw material kneaded clay shown in Table 1 is used as a raw material, the firing temperature is 1250 to 1
350 ° C is preferred. Either oxidation or reduction (or non-oxidation) calcination is possible. If the ceramic raw material is a special fine ceramic material such as silicon nitride, it can be fired in a vacuum furnace or in an inert gas atmosphere such as argon.

After squeezing at about 1150 ° C., the above glazing may be performed and the main calcination may be performed at the calcination temperature. It should be noted that the paper (organic material) is burnt out at about 400 to 600 ° C., and if it is an oxidation firing similar to the normal tile firing, there is almost no problem, but if the paper layer or the stack is thick, it is about 400 to 650 ° C. Until then, it is preferable to make the temperature rising speed slow. In the electric furnace, no problem occurs even at 100 ° C / hour. Also, the porosity due to the ceramic material can be adjusted by changing the firing conditions.

Since all of the above steps can be carried out continuously, the productivity is greatly enhanced. For example, a continuous corrugated board manufacturing apparatus or a known paper tube manufacturing apparatus can be applied.

The ceramic structure obtained by such a manufacturing method has a size due to a jig, a crack or the like such as casting (slip casting) molding using a casting mold such as a plaster mold, and rokuro molding. In addition, there is no limitation in thickness, and it is very suitable for large-scale materials, especially flat structural materials for construction. For example, floor materials, wall materials, ceiling materials, and H-shaped or I-shaped pillar materials. In addition, curved accessory structures such as curved surfaces, steps, and corners can be easily manufactured.

Further, the ceramic structure obtained by the above manufacturing process compensates for the weakness of the strength and impact resistance of the ceramic and brittleness, and realizes weight reduction. In particular, if alumina is used as a component, impact strength is high, and if whiskers or ceramic fibers (for example, carbon, alumina, wollastonite, etc.) are added, the toughness becomes strong. Impact resistance is largely due to the presence of the voids contained in the structure and the base layer that can be formed with the desired porosity. Therefore, it is suitable for applications where ceramics have not been used up to now, that is to say for building materials, in particular self-supporting exterior, interior or facing materials. In fact
INDUSTRIAL APPLICABILITY The ceramic structure according to the present invention greatly surpasses ALC (lightweight foamed concrete) in strength and the like, and is useful as a substitute for ALC, and has a sufficient strength even in a thinner thickness. It can also enter the field of skyscrapers that could not be used. Also, unlike ALC, which requires a steaming process, rust and corrosion do not occur during the manufacturing process even if reinforcing bars are arranged. In the field of tiles, large tiles could not be manufactured due to warpage during the drying and firing steps (usually 30 cm square or less), but according to the present invention, large-sized flat plate tiles can be manufactured.
This is because flat paper can be molded or laminated and has voids. In addition, roof tiles
A thickness of 3 makes it possible to produce a structure or sheet which gives a legal strength. Of course, it can also be used for a catalyst carrier, a jig, etc. which have been conventionally used. Here, in particular, each void contained in the ceramic structure is independent, and if the ceramic sheet forming the outer periphery of the void is continuous, that is, if the void has a continuous pattern, the structural strength is high and uniform, and Particularly preferred as a load-bearing building material. By utilizing the heat insulating property, it is possible to manufacture refractory materials (industrial and architectural) and furnace wall materials.

From another point of view, the present invention does not form a complicated spatial structure (including a planar structure) by shaving by grinding as is conventionally done in the field of jigs. In advance, a shape similar to the final shape can be realized by forming and stacking paper in the manufacturing process beforehand, so the effect of reducing the process is enormous, and cutting and grinding tools are unnecessary or used slightly for finishing. Just do it.

The ceramic structure obtained from the present invention is excellent in fire resistance, heat insulation and strength, and is particularly suitable for construction materials. However, the application of the ceramic structure produced by the present invention is not limited to construction,
It can be applied to a table-like base plate, a heat-resistant wall material as a furnace material, a fire-resistant material, a structural material of machines and devices, and also a chemical reaction catalyst carrier such as a catalyst carrier honeycomb and a deodorizing device carrier. Further, the ceramic sheet produced according to the present invention is also useful as a catalyst carrier for a chemical reaction such as a catalyst carrier honeycomb and a deodorizer carrier. The pore form after sintering can be changed by selecting the ceramic raw material and the organic fiber raw material. For example, in the case of a liquid filtration device, desired pores can be manufactured by adjusting the fibrous material forming pores of relatively large diameter, and in the case of a catalyst carrier related to a gas body, pores of relatively large diameter can be prepared. The desired porosity can be produced by adjusting the fiber quality to be formed. Not only the pores but also the surface can be modified by adjusting the raw materials, and the surface area can be increased to improve the reaction efficiency in the chemical reaction device (support).

[0077]

EXAMPLES The present invention will be described in detail below based on examples.

Example 1 An outline of the method for producing a ceramic sheet and the method for producing a ceramic structure of the present invention will be described. First, the ceramic sheet will be described. The raw material is variously selected according to the purpose properties. In theory,
A ceramic content of 1 to 99% and a fiber content of 1 to 99% can be contained in a weight ratio, but in practice, 5 to 20% of fibers (more preferably 5 to 10% for structures) is suitable. Is. Table 1 shows an example of the raw material composition. In addition, all the following indications are weight ratios.

[0079]

[Table 1]

By adding alumina in this way, the strength can be increased. From the viewpoint of strength, it is preferable that alumina is contained in 10% or more (in the ceramic raw material), and the strength increases as the added amount increases to 20% and 25%. At this time, the fiber content is 5% of the ceramic content
The front and back are preferable in terms of strength after sintering. However, if the fiber content is too small, the moldability becomes poor. Further, diatomaceous earth may be added to further reduce the weight, ceramic fibers or whiskers may be added to further increase the toughness, and metal powder may be added. Alumina may be replaced with steatite (or the entire amount may be replaced) for higher strength. Cordierite has a low coefficient of thermal expansion and is suitable for use as a catalyst support at high temperatures. If mechanical strength is required, the content of cordierite in the ceramic component is about 5 to 45%, preferably about 15 to 45%. If so much strength is not required, the total amount is sufficient and the thermal expansion is greatly reduced.

Other kneaded clay and pulpy materials are shown in Table 2 below. All conventional pottery and porcelain raw materials can be used.

[0082]

[Table 2]

Further, new ceramics can be used as the kneaded material or the added fiber. The inclusion of the ceramic fibers improves the toughness.

[0084]

[Table 3]

The above raw materials are blended according to the purpose of increasing the strength, reducing the weight, reducing the cost, and increasing the heat insulation. For example, when manufacturing a structural material for construction, since strength is required, alumina, steatite, etc. are used. By including the above-mentioned material in the ceramic component at a minimum of about 5%,
The strength of the structure increases. In addition, it is preferable in terms of strength that the fiber content is about 5% or less in weight ratio with the ceramic content. Further, when toughness is required, it is preferable to add ceramic fibers. For example, when a ceramic sheet in which alumina fibers are arranged in a lattice like a woven fabric (which can be produced by the pressing method which is the method for producing a ceramic sheet of the present invention) is used as a structural material, a structure having extremely high toughness can be obtained. You can

When a porous structure is obtained to reduce the weight or improve the air permeability, a large amount of fiber is contained. The maximum width of the fiber component can be 1 to 99% (ratio by weight to the ceramic component), but it is practically 2 to 30%, more preferably 5 to 20%. When high strength is not required, cordierite, mullite, etc. may be contained as a ceramic component. In particular, cordierite has a small thermal expansion and is suitable as a raw material for a catalyst carrier used in an automobile engine or the like to which a thermal shock is applied.

A method for manufacturing a ceramic sheet as one of the raw materials for the above ceramic structure will be described below. The use of the ceramic sheet obtained by such a manufacturing method is not limited to the above-mentioned ceramic structure, and the ceramic sheet can be used alone as a sintered or unsintered ceramic sheet.

FIG. 1A is a schematic sectional view showing a method for manufacturing a ceramic sheet by press molding. A mixture 29 of ceramic powder and organic fibers is placed in a mold 28 and compression molded by a press 27 to obtain a ceramic sheet. When the mixture is a mud containing water, it is dehydrated by a press. The manufacturing method by pressing is a method particularly suitable for obtaining a thick sheet of the cm order. Here, for example, flat paper or cloth may be included as the organic fibers, and a plurality of sheets may be put therein. The ceramic component is impregnated and adhered to the paper (cloth) by press compression. Further, since forced drainage can be carried out by pressing, it is a method suitable for producing a sheet containing a clay component having a high water retention property. In addition,
Either a dry type or a wet type press may be used. According to the pressing method, tiles of cm order (for example, 5 cm thick tiles)
However, it can be easily manufactured without causing defects such as cracks and cracks.
In particular, when this tile-like body is used as an exterior material (outer wall, etc.), it is possible to increase the strength and form a protective layer by adhering mud containing a ceramic component during the molding and firing of the ceramic sheet.

FIG. 1 (b) is a schematic sectional view showing a method for producing a ceramic sheet by the doctor blade method.
The flat paper 21 is supplied from the paper roll 32, and the slurry 34 containing the organic fiber and the ceramic powder is dropped on the paper 21 from the sludge container 30 on the way. Then, the excess slurry is scraped off by the doctor blade 31, and the ceramic sheet 4 having a predetermined thickness is completed and wound on the ceramic sheet roll 33. The paper 21 to be supplied may of course be one containing organic fibers such as cloth, and may be a chemical film such as polyethylene or polyester as long as the organic fibers are contained in the slurry 34. Since the raw material contains organic fibers, it has a high shape-retaining power, and it is easy to obtain a relatively thin sheet.

FIG. 1C is a schematic sectional view showing a method for producing a ceramic sheet by a roll rolling method. Paper 21
And ceramic powder 20 are supplied to a rolling roll 25, and when rolled, the ceramic material is impregnated or adhered / fixed to the paper,
Further, it is dried and molded by the heating roll 26 to form the ceramic sheet 4. Here, the paper 21 may be cloth,
Further, it may be a chemical film such as polyethylene or polyester, or a warif (sheet-shaped material obtained by tearing the film). That is, if the sheet-like material is paper, cloth, or the like made of organic fibers, the mixture containing ceramic raw materials (powder, mud, gel, etc.) as a main component may not contain the organic fibers. On the other hand, in the case where the sheet-like material is a chemical film containing no organic fibers such as polyethylene and polyester, the organic fibers are contained in at least one of the mixtures.
This method is particularly suitable for continuous mass production. Further, since forced drainage can be carried out by pressing, it is a method suitable for producing a sheet containing a clay component having a high water retention property. The press may be either a dry type or a wet type.

As a raw material of the above-mentioned ceramic sheet,
The same ingredients as the raw materials for the ceramic structure are used (Table 1
And 2).

The ceramic sheet used in the present invention can also be obtained by papermaking and slip casting. The method of papermaking may be any known method and is not particularly limited, but is usually a wet papermaking method or a semi-wet papermaking method.

The manufacturing method of the ceramic structure of the present invention will be described below. Step 1 is a forming process of a ceramic sheet forming object for forming a paper into a desired shape. By this step, a forming step such as a grinding step after firing becomes unnecessary or is essentially reduced, and only a finishing step is required when necessary.

In the present invention, a coating process can be included between steps 1 and 2. When the ceramic sheet molded body is again coated (attached) with mud containing the same or similar components as the raw material and fired, each ceramic sheet is reinforced with a more dense ceramic coating, and the overall reinforced ceramic A structure is created.

Further, it is possible to apply a glaze to the ceramic sheet molded article to give it an exterior appearance and color to give it a beautiful appearance, and to enhance the strength and water resistance after firing.

Step 2 is a firing step of firing the molded body in a furnace. The molded body is fired in a predetermined atmosphere. The temperature can be changed according to the sintering temperature of the raw material.
When the high-strength porcelain raw material kneaded clay shown in the table is used as a raw material, the firing temperature is preferably 1250 to 1350 ° C. Needless to say, the firing temperature can be adjusted by the desired degree of sintering (that is, the porosity of the sintered body). As a result, the finished sintered body can be fired from one having a porosity of unglazed level to one having a denseness which is not absorbable upon completion.

Also, after squeezing or unglazed at around 1150 ° C.,
Glazing as described above may be performed and main firing may be performed at the firing temperature.

By the way, the organic components (organic fibers) of the ceramic sheet are burnt off at around 400 to 600 ° C.

Example 2 A method for making a ceramic sheet, which is a raw material for the ceramic structure of the present invention, and its material will be described.

The raw materials are alumina 15 to 45% and feldspar 15
.About.35%, clay or kaolin 25 to 45%, and sericite 0 to 10%. 3 such ingredients
After finely wet-milling to 0 μm or less, it is passed through a sieve of 325 mesh or less to obtain coarse particles from which coarse particles causing a decrease in strength have been removed. On the other hand, Manila hemp is used as the fiber for the paper stock.

These raw materials are subjected to papermaking by a usual papermaking method (consisting of a screen making step for forming a wet paper web, a pressing step for squeezing water, and a drying step). That is, the above raw materials are mixed, water is added to form a slurry, and a ceramic sheet (thickness: 0.1 mm to 5 cm, usually 2 to 3 mm) is obtained by a soaking method and dried.

As the paper machine, a Fourdrinier paper machine, a cylinder paper machine, a twin wire machine, a combination machine and the like are used. In addition, it is also preferable that the cation is modified and beaten before papermaking, and the fixing rate of the kneaded clay particles to the fiber is increased.

Further, it is possible to make a paper having a predetermined gap, a paper having a non-uniform thickness, a paper having a pattern, or the like.

In addition to the kneaded clay having the above composition, of course, the composition shown in Table 1 of Example 1 or the raw material shown in Table 2 may be used. In particular, alumina has a large effect of increasing strength and is suitable as a building material. Further, it is preferable to use bast pulp such as Manila hemp and jute in order to make the ceramic sheet to be made particularly tough.

Further, the above-mentioned ceramic powder-based ceramic sheet is preferable, but the ceramic fiber-based or ceramic fiber-powder-based paper described in Table 3 or the like, or the paper to which the components are added is also provided in the molding step of the present invention. it can.

<Third Embodiment> A molding process of a ceramic sheet molded article according to the first or second embodiment will be described. FIG. 2 is a schematic process drawing showing a method for producing a corrugated plate-shaped ceramic sheet by the corrugated method.

In (a), two plate-shaped ceramic sheets are used.
The corrugated sheet is processed through the roller 10 of the book (corrugated sheet 6). A corrugating machine for producing corrugated paper can be used as this corrugating machine.

In (b), the corrugated plate 6 is bonded onto the ceramic sheet flat plate 4. Further, another flat plate is bonded onto the corrugated plate. In this way, the ceramic sheet molded body 7 (structure) containing a large number of voids is completed. In addition, this process can be performed by a process similar to a known corrugated paperboard manufacturing process.

In (c), the corrugated plate obtained in (a) is cut or sliced in a direction orthogonal to the wave peaks (cut corrugated plate 8).
These semi-annular ceramic sheets are arranged and joined by setting the paper surface on another ceramic sheet flat plate 4 and bringing the end faces of the wave fronts into contact with each other. By further adhering (not shown) another ceramic sheet flat plate 4 on this, a ceramic sheet molded object 7 (structure) containing a large number of voids is completed.

Further, the steps (a) and (b), (a) and (c), or (a) to (c) can be continuously performed, and mass production is possible.

Although the corrugated plate has a sandwich structure of two ceramic sheet flat plates, the corrugated plates may be bonded to each other or one flat plate may be used.

In order to form the corrugated plate structure, drawing processing such as punching processing may be used.

FIG. 3 shows various ceramic sheet molded objects 7 using corrugated plates produced by the corrugated method.

(A) is a laminate in which the corrugated plates are shifted by one-half wavelength in the circumferential direction and the crests of the waves of the adjacent layers are brought into contact with each other. It is also possible to stack at the same wavelength. It is also possible to change the wavelength of each corrugated plate. (B) is 90 degrees in the direction of the mountain
° Rotate each other and cross-laminate. The crossing angle is not limited to 90 °. (C) is obtained by adhering or sandwiching flat plates between corrugated plates in (a) laminated at the same wavelength. (D) is obtained by adhering or sandwiching flat plates between the corrugated plates in (a), which are laminated with a shift of half wavelength.
(E) is a product obtained by adhering a corrugated plate onto a flat plate and winding it up. These structures, that is, the relative arrangement of the corrugated plates and flat plates are determined by the application of the product. Then, these structures can be composed of ceramic sheets having the same thickness as a whole, and in that case, shrinkage during firing becomes uniform, and generation of strain is suppressed. In addition, in the case of bonding ceramic sheets to each other, it is preferable that the kneaded clay component (friend soil) and sugar alcohol are in a moisture state, but other organic adhesives (epoxy resin, vinyl resin, rubber resin, etc.) Inorganic adhesives (mortar, silicon, water glass, etc.) can also be used. Further, the above-mentioned adhesive can be used even when it is bonded to other than the ceramic sheet. Further, they may be mechanically fitted and engaged, or may be joined by fusion.

In addition to the ceramic sheet of the present invention, a ceramic sheet prepared by another method can be used for the flat plate, and it becomes a composite material.

The ceramic sheet molded body 7 (structure) having a structure containing voids can also be manufactured by pressing, drilling or cutting. That is, a plurality of ceramic molded objects (multilayer ceramic sheets) laminated by adhesion, pressure bonding, etc. are punched and cut by a press to cut or cut a die having a desired shape. This results in a structural element containing a large number of voids. The element can be fired as such into a structure, or the element can be used as a core to make a structure. Alternatively, the ceramic sheet molded body 7 can be obtained by press-cutting a single sheet and then stacking it.

It is possible to obtain a structure by forming an uneven sheet by embossing (pressing) instead of press die cutting or the like, and by replacing it with a corrugated corrugated sheet or by using it in combination. FIG. 4A shows a cross-sectional view of the ceramic sheet molded body 7 formed of the embossed sheet 11 by embossing.

Since the ceramic sheet has not yet been fired and hardened, it can be easily formed by punching, cutting, embossing, etc., and can have a triangular, square, pentagonal, hexagonal or more polygonal shape, or a round or oval shape. Ceramic sheet molded objects 7 having various other cross-sectional shapes can be formed.

That is, similarly to the above, after drilling a single sheet or a plurality of sheets, they can be laminated to obtain the ceramic sheet molded body 7. In this way, various shearing processes can be performed. In FIG. 4 (b), one ceramic sheet is folded and overlapped (folded ceramic sheet 1
9) Then, a predetermined shape (semicircle) is cut (hollowed out) and again developed into one sheet (ceramic sheet 4 having voids), and a ceramic sheet molded object containing voids by stacking a plurality of them 7 schematically shows the step of obtaining 7.

5 (a) to 5 (d) are schematic process diagrams for obtaining the ceramic sheet molded body 7 from the cylindrical, tubular or annular ceramic sheet tube (cylindrical) 12.

First, a tubular body (cylindrical body) is manufactured from a ceramic sheet. Next, slice it in the circumferential direction (13)
(FIG. 5A). A ceramic sheet molded body 7 can be obtained by adhering these end faces to a ceramic flat plate. A ceramic sheet molded article can be obtained by simply stacking tubular bodies with their axes parallel. The tubular body or the aggregated bundle thereof may be formed by a known honeycomb extrusion molding method. According to the present invention, the formed tubular body (or the tubular body) can be further assembled into a structure. It is advantageous.

(B) is a ceramic sheet molded body 7 cut in the axial direction.

The ceramic sheet can be cut into strips (or formed into a string) and directly rolled into an annular shape to be planted in a ceramic flat plate shape, as shown in FIGS. 5 (a) and 5 (b). Thus, a structure (ceramic sheet molded object) can be formed (see also FIG. 2C).

(C) is a ceramic sheet molded body 7 in which a large number of paper beads, that is, a small annular ceramic tubular body (cylindrical body) 12 is enclosed by a flat ceramic sheet 4 and a large number of voids are enclosed. The process of doing is shown. The paper beads may be formed into an annular shape at the time of making a ceramic sheet, or a flat plate-shaped (unformed) ceramic sheet may be rolled into an annular shape afterwards. Also, the outer diameters of the paper beads do not have to be the same size, and may be random. The randomness may increase the filling rate and may be preferable. The outer diameter of the paper beads is usually several millimeters to several centimeters, but depending on the desired size of the ceramic structure, an annular body having an outer diameter in the unit of several meters is also possible due to the high degree of processing freedom of the ceramic sheet. In addition, in the figure, many small annular ceramic tubular bodies are wrapped with flat paper, but many small annular ceramic tubular bodies (cylindrical bodies) are inserted into the ceramic tubular body (cylindrical body) itself. , May be filled.

(D) shows that a large number of pipes, that is, elongated ceramic tubular bodies (cylindrical bodies) 12 are enclosed by a flat ceramic sheet 4 to form a ceramic sheet molded body 7 containing a large number of voids. A process of forming a ceramic sheet molded body 7 by cutting it in the circumferential direction will be described. This pipe may be formed into a tubular shape when the ceramic sheet is made, or a flat (unformed) ceramic sheet may be rolled into a tubular shape afterwards. Further, the pipes do not need to have the same size such as the outer diameter, and may be random. The randomness may increase the filling rate and may be preferable. The outer diameter of the pipe is usually a few millimeters to a few centimeters (can be manufactured in μm units), but depending on the desired size of the ceramic structure, an annular body with an outer diameter of several m units also has a high degree of freedom in processing the ceramic sheet. Is possible. In addition, in the figure, many small annular ceramic tubular bodies are wrapped with flat paper, but many small annular ceramic tubular bodies (cylindrical bodies) are inserted into the ceramic tubular body (cylindrical body) itself. , May be filled.

[0126] Further, the ceramic sheet molded object 7 obtained by the above-mentioned sliced process is arranged in a flat ceramic sheet shape, or sandwiched between upper and lower flat ceramic sheets and divided into a plurality of ring-shaped blocks. It is possible to obtain a ceramic sheet molded body containing a large number of voids.

As described above, a honeycomb structure having a structure similar to that of the honeycomb structure is obtained from the above steps.

Further, since the pipe, that is, the elongated ceramic tubular body (cylindrical body) is made of a ceramic sheet, it is expressed by the formula
Since a product having a length (axial length) of m units or more can be easily manufactured, it is possible to manufacture a ceramic sheet molded object and also a huge ceramic sintered body (structure) after firing. In addition to building materials, its applications include reactors in chemical plants. In the case of a reactor, it is preferable that it is relatively porous because it has a large surface area.

Furthermore, a ceramic sheet molded article having a lath shape can be obtained by using a lath sheet in which a plurality of cuts are made in a ceramic sheet and at least one of them is stretched to form a mesh shape.

Also, various complicated three-dimensional shapes and structures can be easily realized by cutting and pasting the pattern paper. If necessary, a flat ceramic sheet is used as a cover material.

[0131] It is also possible to directly obtain a ceramic sheet having holes directly from the paper making step and laminate the sheets to form a structure in which voids are included. Since the ceramic sheet has flexibility and self-supporting property, even if such a hole is formed, it has strength and can maintain self-supporting property. This method is preferable because it can reduce the number of drilling steps.

For the purpose of surface strengthening, preferably
For the ceramic sheet molded object (structure) as described above,
Cover mud. The coating can be applied (attached) by dipping, coating, spraying, or the like. As a result, the paper-type pores absorb the mud and the pores are filled, so that the one having a dense coating layer can be fired. The part to be attached may be the entire surface (entire surface) or only the surface layer (surface). Both of them serve as protective layers and have improved strength and environmental resistance, and exhibit excellent properties especially when used as building materials.

If a relatively porous structure is desired, the above-mentioned sludge coating step can be omitted. A porous, lightweight, and large surface area ceramic structure can be obtained, which is particularly suitable for a chemical reactor such as a catalyst carrier. Of course, since it has sufficient strength, it is also useful as a building material.

As the component of the mud, it is preferable to use, in addition to the kneaded material which is the raw material of paper, for example, a peptizer of about 0.3% and cellulose powder of 3% to make mud with a water content of 36%. it can. Examples of the components of the peptizer include phosphoric acid type, polycarboxylic ammonium type, polyacrylic acid type and the like.

Example 4 The ceramic sheet molded body obtained in the above example is fired. The paper mold is fired in an oxidizing atmosphere. The temperature varies depending on the raw material. Both oxidation and reduction firing are possible. The firing can be performed in a vacuum furnace or in an atmosphere of an inert gas such as argon. However, an organic substance removing step (so-called degreasing step) may be required in a vacuum furnace or an atmosphere furnace other than an oxidizing atmosphere.

When the ceramic sheet has the composition shown in Table 1, the paper molded article is dried, then calcined at about 800 to 1200 ° C., and finally calcined at about 1200 to 1400 ° C. Although this embodiment also depends on this, the firing conditions naturally vary depending on the paper mold (structure of the structure) and the material, thickness, size, etc. of the ceramic sheet.

In the fired paper mold, the core organic fiber (cellulose fiber or the like) which is the paper layer 2 is burned to become porous, but is sandwiched between the dense coat layers (ceramic layer 1) on both sides. Sintering produces a ceramic structure that is similar to the original paper molded body. Moreover, it is light due to the pores in the middle layer. FIG. 6 shows an example of a structural diagram for observing a cross section of the fired ceramic sheet with a microscope. As described above, the surface layer (both layers in this figure, but a single layer is also possible) can be provided with glaze (glaze layer 3) for surface mounting.

The unit layer of this ceramic structure has a thickness of about 0.8 mm and is very thin, strong, and heat resistant.
A material with excellent water resistance and chemical resistance can be obtained. 2 in JIS R1601 fine ceramic bending strength test of this material
It shows 100 to 2800 (average 2300) kgf / cm ² . The compressive strength can be adjusted by the structure of the core.

<Embodiment 5> FIG. 7 shows a sectional structure in the thickness direction of a ceramic structure 17 containing voids obtained by the manufacturing method of the present invention. As shown in Example 3, the paper mold can be formed into various shapes (structure having voids). As shown in the figure, it is preferable that the voids are arranged continuously and symmetrically from the viewpoint of high strength, uniformity, and production efficiency. However, depending on the application, a large number of voids may be arranged asymmetrically or discontinuously. preferable.

(A) is a ceramic structure 7 having a void formed of a circular continuous body as an application example of a tubular void.

(B) is a ceramic structure 7 having a void formed of a sharpened triangular continuous body as a wavy modification.

(C) is a ceramic structure 7 having a space formed of a triangular continuous body having a flat plate-shaped tip portion as a waveform modification. If it is a continuous body, it is excellent in strength.

(D) is a modification of (a) and is a ceramic structure having curved surfaces (corners). As described above, a bent product can be provided by the manufacturing method of the present invention.

Since the structures (a) to (d) have sufficient strength even with a large flat plate, they can be used as a single layer or as a plate-like body, and the surface is used as a dense coat layer (ceramic layer 1). It can be covered (see Figure 6) and is very suitable for building materials.

Further, the cross-sectional structure of the ceramic structure having a large number of voids is, in addition to a substantially mountain wave shape, a tubular shape, a polygonal shape such as a circle, an ellipse, a triangle, a square, a pentagon, and a hexagon, a spiral shape, a coil shape, and a mesh. Shapes, H-shapes, X-shapes, etc. are adopted depending on the application.

(A) to (d) having these cross-sectional shapes
These structures can be used alone or in combination. That is, they may be assembled, polymerized, or laminated.

Further, since a large-scale plane structure can be easily prepared without using a mold and a mold, the effect of reducing the process and the construction cost is very large.

Example 6 Furthermore, a surface layer material such as a tile or a porcelain plate can be attached to the fired ceramic structure. A tenon or the like for fitting and engaging the paper-molded object may be provided in advance to join them together. A ceramic sheet having voids for mortises or the like may be previously made into paper.

Further, by inserting the ceramic sheet tubular body into the voids inside the structure (for example, the corrugated voids in FIG. 2) and firing it, reinforcement is possible and strength is imparted. Further, by using bolts, nuts, etc., the reinforced structures can be connected to form a larger structure. Such a structure becomes a seismic resistant structure due to the reinforcement of the ceramic tubular body, and the effect of beam and streaks by inserting reinforcing bars inside or between the tubular bodies.

Example 7 The ceramic structure according to the present invention can be particularly preferably used as a building material. That is, it can be used as a plate-like body such as a floor material, a wall material, a ceiling material, or a facing material. Further, it may be a pillar material having a rod shape, a column shape, or a hexagonal column shape. The ceramic structure obtained from the present invention is
It has a structure that contains a specified void, is lightweight, has high mechanical strength, high impact resistance, excellent incombustibility, heat insulation, heat retention, and water resistance, and satisfies all the properties required for building materials. To do. For example, it greatly exceeds ALC (lightweight foamed concrete) in terms of strength and the like, and is useful as a substitute for ALC. Moreover, it can also enter the field of super high-rise construction where ALC could not be used due to insufficient strength. In fact, the bending strength test of ALC panel of JIS A5416,
Outer wall 200 kgf / m ^2, partition 65 kgf / m ^2, the roof 100 kgf / m ^2, both the reference floor 360 kgf / m ² can be cleared. It can also be used as a catalyst carrier, a firing jig and the like.

[0151]

According to the method of manufacturing a ceramic sheet and a ceramic structure of the present invention, firstly, inexpensive organic fiber can be used as a raw material. Then, in the method for producing a sheet, a ceramic sheet excellent in flexibility and self-sustaining property and shape retention is obtained by mixing and processing it with a ceramic raw material, and a good material for the structure of the present invention is obtained. Become. Further, the morphology of the pores can be adjusted by changing the composition of the ceramic material and the organic material. Further, in the case of containing a highly water-retaining ceramic material, a sheet can be formed by pressing or rolling to expel water by pressing and drying. Further, a single sheet sintered is also a porous body having a large number of minute voids, and is provided as a chemical reaction device. Furthermore, the structure of the present invention has a structure containing a predetermined void, is lightweight, has high mechanical strength, high impact resistance, excellent incombustibility, heat insulation, heat retention, and water resistance. It satisfies all the properties required for materials.

Also, waste paper can be used as the organic fiber,
Suitable for recycling and can contribute to environmental protection.

Furthermore, if alumina is used as the ceramic raw material, a high-strength ceramic structure can be obtained. It has a bending strength of 2100 to 2800 kgf / cm ² .

If the ceramic sheet is made so as to have voids (holes), it is possible to easily fire a ceramic structure having a structure containing voids simply by stacking them.

Secondly, since the ceramic sheet containing organic fibers and ceramic raw materials as its main components is excellent in flexibility and self-supporting property, it can be formed into a corrugated plate by corrugation or the like. , By laminating with each other or with a flat ceramic sheet,
Since it is not necessary to grind and cut a hard ceramic sintered body after firing, it is possible to eliminate the grinding step for forming the spatial structure of the ceramic structure, and a grinding tool that has been conventionally used for grinding ceramics, which is a high hardness brittle material. Since a problem such as frequent tool replacement due to wear of the ceramic sheet does not occur, a ceramic sheet molded object (structure) having a structure including voids, which is a firing original shape, can be inexpensively and easily formed. Furthermore, a structure having a curved surface can be easily manufactured due to the flexibility of the ceramic sheet. In addition, the above steps can be performed continuously and are excellent in productivity.

A ceramic sheet die having a structure in which a single sheet or a plurality of ceramic sheets is die-cut by a cutter, a press or a drill, and is left alone or laminated to enclose a large number of voids without a grinding and cutting step. Can be easily molded.

Further, by taking advantage of the good cuttability of the ceramic sheet, a tubular (cylindrical) ceramic sheet is sliced, or a string-shaped ceramic sheet is joined into a tubular (cylindrical) shape, and the flat ceramic sheet is formed. It is possible to obtain a structure that is planted in a column shape and has a void therein.

In any of the above ceramic sheet molds containing voids, the voids can be arrayed continuously,
Excellent in strength such as compressive strength.

Thirdly, by immersing the molded paper molded body (structure) in the mud made of the ceramic raw material, the pores of the ceramic sheet absorb it, and a more dense protective layer is formed after firing. A ceramic plate-shaped sintered body (structure) having the same can be obtained.

Fourthly, in the ceramic structure fired by the "third" method, the intermediate layer in the thickness direction is burned by the organic fibers to become porous, but is sandwiched between the dense ceramic layers on both sides. The original structure is maintained and the intermediate layer is almost hollow, so a very light structure can be obtained. Of course, since the outer surface (both sides) is a dense ceramic layer, chemical resistance,
Excellent impact resistance, light weight, strength, water resistance, heat insulation and fire resistance.

Using the structure obtained by the manufacturing method of the present invention as a core, a surface material such as tile, marble, resin, wood, etc. is used, or a glaze or a glaze is decorated with a pattern etc. It is possible to improve decorativeness and the like. Alternatively, the surface of the structure of the present invention can be directly glazed.

In addition, the space in the structure can improve heat insulation, soundproofing and fire resistance, and can also be used as a ventilation wall material, so that the heating efficiency can be increased by the so-called ondol effect and the cooling effect can be obtained. Can be raised and air-conditioned. By passing cold air or hot air through the floor and walls, it is possible to improve the air conditioning effect such as cooling and heating, and it is also possible to remove humidity and humidity. Moreover, if a predetermined cavity is provided by a paper tube or the like, it can be used as a space for wiring and piping.

[Brief description of drawings]

1 is a process schematic diagram showing a method for producing a ceramic sheet according to the present invention, FIG. 1 (a) is a schematic sectional view showing a method for producing a ceramic sheet by press molding, and FIG. ) Is a schematic cross-sectional view showing a method for manufacturing a ceramic sheet by a doctor blade method, and FIG.
(C) is a schematic cross-sectional view showing a method for manufacturing a ceramic sheet by a roll rolling method.

2A and 2B are schematic process diagrams showing a method for producing a corrugated plate-shaped ceramic sheet and a molded object by a corrugated method according to Example 2 of the present invention. In FIG. 2A, the plate-shaped ceramic sheet is provided with two rollers 10. It is a schematic process drawing which shows the manufacturing process (corrugated plate 6) processed into a corrugated plate shape through. In (b), the corrugated plate 6 is adhered onto the ceramic sheet flat plate 4, and another flat plate is further adhered onto the corrugated plate to obtain a ceramic sheet molded body 7 (structure) containing a large number of voids. It is a schematic process drawing which shows a manufacturing process. In (c), the corrugated plate obtained in (a) is cut or sliced in the direction orthogonal to the wave peaks (cut corrugated plate 8), and these semi-annular ceramic sheets are placed on another ceramic sheet flat plate 4. It is a schematic process drawing which shows the manufacturing process which obtains the ceramic sheet molded object 7 (structure) which arranges and joins by making a paper surface stand and contact | abutting the end surface of a wave surface, and arranging and joining.

3 (a) to 3 (e) are perspective sectional views of various ceramic sheet molded objects (structures) using corrugated plates produced by the corrugated method according to the first embodiment of the present invention.

FIG. 4 (a) is a perspective view showing a ceramic sheet-type molded article having a structure for enclosing voids formed by embossing according to a second embodiment of the present invention, and FIG. 4 (b) shows a single ceramic sheet bent. FIG. 3 is a schematic process diagram showing a process of forming a ceramic sheet molded body containing voids by cutting, polymerizing, and cutting.

5 (a) to 5 (d) are schematic process diagrams for obtaining a ceramic sheet molded article (structure) from a cylindrical ceramic sheet tube according to Example 3 of the present invention, and FIG. A process of obtaining a ceramic sheet molded body 7 by cutting a tubular body (cylindrical body) into a circle in the circumferential direction and adhering these end faces to a ceramic flat plate will be described. (B) is a ceramic tubular body (cylindrical body) cut in the axial direction to form a ceramic sheet molded body 7. (C) shows a process of enclosing a large number of small annular ceramic tubular bodies (cylindrical bodies) with a flat ceramic sheet to obtain a ceramic sheet molded body 7 enclosing a large number of voids. In (d), a large number of elongated ceramic tubular bodies (cylindrical bodies) are enclosed in a flat ceramic sheet to form a ceramic sheet molded body 7 containing a large number of voids, which is further sliced in the circumferential direction. A process of forming the ceramic sheet molded body 7 will be described.

FIG. 6 shows a structural diagram of cross-sectional observation by a microscope of a ceramic sheet after firing according to Example 4 of the present invention.

FIG. 7 is a sectional view showing a sectional structure in a thickness direction of a ceramic structure having a structure including voids according to a fifth embodiment of the present invention, wherein (a) to (c) are linear plate-shaped bodies. And
(D) is a curved plate-shaped body.

[Explanation of symbols]

 1 Ceramic Layer 2 Paper Layer 3 Glaze Layer 4 Ceramic Sheet 5 Roller 6 Corrugated Plate 7 Ceramic Sheet Formed Object (Structure, Plate) 8 Cutting Corrugated Plate 9 Laminated Ceramic Sheet 11 Rough Corrugated Plate 12 Ceramic Hollow Tube (Cylinder) 13 Horizontally Divided Ceramic Hollow Tube (Cylinder) 14 Vertically Divided Ceramic Hollow Tube (Cylinder) 17 Ceramic Structure (Plate) 19 Bent Ceramic Sheet 20 Ceramic Powder 21 Paper (Cloth) 25 Pressure Roll 26 Heating Roll 27 Press 28 Mold 29 Mixture 30 Slurry container 31 Doctor blade 32 Paper roll 33 Ceramic sheet roll 34 Slurry

Continuation of front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display area C04B 35/80 38/06 41/89 Z E04C 2/36 G 7806-2E

Claims (30)

[Claims] 1. A molding step of forming or not forming a ceramic sheet containing organic fibers and a ceramic raw material as a main component, or a ceramic sheet of the both, into a ceramic sheet forming object containing a large number of voids, and firing the forming object. And a firing step for forming a ceramic structure containing a large number of voids. 2. The molded ceramic sheet has voids, and the molded ceramic sheet is polymerized in the molding step to mold a ceramic sheet molded object having a predetermined void. A method for manufacturing a ceramic structure according to item 1. 3. The forming step includes a step of processing a ceramic sheet into a substantially corrugated plate shape, and a step of including at least one substantially corrugated plate-shaped ceramic sheet and superposing the same on a plurality of layers. Item 3. A method for manufacturing a ceramic structure according to any one of Items 1 and 2. 4. The molding step includes a step of processing a ceramic sheet into an uneven shape by embossing, and a step of including at least one layer of the uneven ceramic sheet and laminating it into a plurality of layers. The method for manufacturing a ceramic structure according to any one of 1 to 3. 5. In the forming step, at least a tubular ceramic sheet is used as the formed ceramic sheet,
The method for manufacturing a ceramic structure according to any one of claims 1 to 4, wherein a ceramic sheet molded body including a plurality of tubular ceramic sheets is molded. 6. The forming step integrally comprises a step of processing a ceramic sheet into a tubular shape, and a plurality of tubular ceramic sheets integrated with or without at least one flat plate-shaped or uneven ceramic sheet. The method for manufacturing a ceramic structure according to claim 1, further comprising a step of bonding. 7. A three-dimensional structure in which the forming step includes a step of cutting at least one ceramic sheet into a predetermined shape, and the ceramic sheet cut into the predetermined shape is bonded onto at least one ceramic sheet. 7. The method for manufacturing a ceramic structure according to claim 1, wherein the ceramic structure is formed. 8. The method for producing a ceramic structure according to claim 7, wherein a ceramic sheet having a porous or predetermined pore pattern is formed by the cutting. 9. The method for manufacturing a ceramic structure according to claim 7, wherein the tubular ceramic sheet is molded into a molded object including a cut product obtained by bundling one or more of the tubular ceramic sheets. 10. The method for producing a ceramic structure according to claim 9, wherein a plurality of the cut pieces are formed into a formed body through at least one layer of the ceramic sheet. 11. A ceramic structure according to claim 10, which comprises at least a porous molded ceramic sheet obtained by folding back a ceramic sheet into two or more layers, cutting it, and then partially expanding it. Production method. 12. A lath sheet formed by making a number of cuts in a flat ceramic sheet and then stretching the flat ceramic sheet in at least one direction as at least a part of the shaped ceramic sheet. 11. The method for manufacturing a ceramic structure according to any one of 1 to 11. 13. The ceramic sheet molded body is molded in the molding step so as to include continuous voids arranged as independent voids.
13. The method for manufacturing a ceramic structure according to any one of 12. 14. The method for manufacturing a ceramic structure according to claim 1, wherein a flat ceramic sheet is used as the mounting material. 15. An intermediate layer comprising at least one flat ceramic sheet.
A method for manufacturing a ceramic structure according to any one of 1. 16. The method for manufacturing a ceramic structure according to claim 1, wherein the structure is a plate-shaped body. 17. The method for manufacturing a ceramic structure according to claim 1, wherein the plate-shaped body is a building wall material, a pillar material, or a block-shaped material. 18. The method for producing a ceramic structure according to claim 1, wherein the organic fibers are cellulose fibers or synthetic or artificial fibers. 19. The ceramic raw material has a porcelain composition containing alumina as a component.
19. The method for manufacturing a ceramic structure according to any one of 18 to 18. 20. The method for producing a ceramic structure according to claim 1, wherein an organic or inorganic binder or a mixture thereof is used as an adhesive in the molding step. 21. The ceramic structure is glazed after or before firing.
A method for manufacturing a ceramic structure according to any one of 1. 22. A coating step for coating at least a portion of a ceramic sheet layer of the ceramic sheet molded article with a ceramic material sludge.
22. The method for manufacturing a ceramic structure according to any one of 21 to 21. 23. A method for producing a ceramic sheet, characterized in that a mixture containing organic fibers and a ceramic raw material as a main component is pressed and bonded to obtain a ceramic sheet. 24. The method for producing a ceramic sheet according to claim 23, wherein during the pressing, embossing is performed to obtain an uneven shaped ceramic sheet. 25. A ceramic sheet characterized in that a mixture containing organic fibers and a ceramic raw material as main components is flown down onto a sheet-like material, and the mixture flowed down by a doctor blade is used as a ceramic sheet having a predetermined thickness. Manufacturing method. 26. A mixture containing at least one of organic fibers as a main component of a ceramic raw material and a sheet-like product are rolled so that the mixture is impregnated or adhered to the sheet-like product, and the mixture has a predetermined thickness. A method for producing a ceramic sheet, which comprises obtaining a ceramic sheet. 27. The method for producing a ceramic sheet according to claim 26, wherein the sheet-like material is made of organic paper, cloth or non-woven fabric. 28. The method for producing a ceramic structure according to claim 1, wherein the ceramic sheet obtained by the method according to any one of claims 23 to 27 is used. 29. A ceramic structure obtained by the method according to any one of claims 1 to 22 and 28. 30. A ceramic plate-like structure obtained by firing the ceramic sheet obtained by the method according to claim 23.