JPH0339801B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing ceramic plates such as tiles, and a mold used therein.

[Conventional technology]

Ceramic plates, especially tiles having a three-dimensional pattern such as an uneven pattern on the surface, are generally formed to a size of 100 mm square, and are manufactured in the following manner. In other words, a clay raw material of which 95% or more is composed of fine particles with a particle size of 40 to 50 μm or less, a felsic raw material composed of fine grains (feldspar, silica, etc.), and raw materials such as talc, dolomite, lime, etc. A ceramic raw material composition with a water content of Forms a molded article consisting of a solid component. Next, the molded article is removed from the mold by suction using a suction cup or the like, dried, and then placed in a firing furnace and fired. This manufacturing method is particularly used for manufacturing tiles that have a three-dimensional pattern on the surface, and in that case, the water-permeable dish-shaped mold has an uneven pattern on the bottom surface for transferring the three-dimensional pattern. A three-dimensional pattern is formed on the tile surface by transferring the uneven pattern.

[Problem that the invention seeks to solve]

However, when manufacturing tiles as described above, the raw materials used for the ceramic raw material composition are fine particles as described above, so when draining, the fine particles are transferred to the water-permeable dish-shaped mold. water passageway (voids formed between the molecules of gypsum)
At the same time, it becomes difficult to drain water and takes a long time to manufacture.
The problem is that the resulting molded product has a high moisture content and may collapse during demolding.

The present invention has been developed in view of the above circumstances, and is intended to prevent clogging of the water passage of a water-permeable dish-shaped mold, and prevent chipping and deformation due to adhesion to the mold when demolding a molded product. Its purpose is to.

[Means for solving problems]

In order to achieve the above object, the present invention places a clay-like ceramic raw material composition in a water-permeable dish-shaped mold, drains the water, and produces a molded article made of the solid components of the ceramic raw material composition described above. A method for manufacturing a ceramic plate in which a ceramic plate is produced by forming the molded product in a mold, demolding it, drying it, and firing it. The first gist is a method for producing ceramic plates, which is characterized by using a thin layer of cellulose fibers deposited in the mold by placing the fibers in a mold, draining water, and drying them. The second gist is a mold consisting of a water-permeable dish-shaped body having a concave-convex pattern formed on the bottom surface for the purpose of cleaning, and a cellulose fiber filter thin layer formed on the inner surface of this water-permeable dish-shaped body. do.

That is, according to the present invention, an aqueous solution of cellulose fibers is poured into the mold as described above as a dish-shaped mold having water permeability, and the water is drained and dried to form a thin deposited layer of cellulose fibers in the mold. When the ceramic raw material composition is put into the mold and drained to form a molded product, the fine particles of the ceramic raw material composition are captured by the deposited layer of cellulose fibers, forming a water-permeable dish-shaped product. It will not get into the mold's water passage. Therefore, the clogging of the water passage is prevented, and the ceramic raw material composition is always well drained, and the molded product is also sufficiently drained, resulting in a low moisture content and smooth molding. In addition to obtaining a good surface, the occurrence of a situation where the shape collapses during demolding can be prevented. Moreover, manufacturing time can also be shortened.

The ceramic plate of the present invention is produced by placing a clay-like ceramic raw material composition in a water-permeable dish-shaped mold in which a thin deposited layer of cellulose fibers is formed as a thin filter layer, and draining it. It is manufactured by forming a molded article from the solid components of the ceramic raw material composition, demolding the molded article, then drying and firing it.

The kneaded clay-like ceramic raw material composition is prepared by kneading the previously-known clay raw materials, silica powder, felsic powder raw materials made of feldspar, etc., and conventional ceramic raw materials such as talc by a conventionally known method. A material whose moisture content is appropriately adjusted is used.

In addition, the water-permeable dish-shaped mold into which the clay-like ceramic raw material composition is placed may be a mold made of a water-permeable material such as gypsum, or a mold made of foamed urethane resin, polyester resin, or epoxy resin. A mold made of plastic resin is used. In the above-mentioned mold made of plaster, the voids formed between the molecules of the plaster serve as passageways, and in the case of molds made of foamable resin, the air bubbles are closed cells. The area around the bubble becomes a water passage, and if the bubble is open, the bubble itself becomes a water passage.

The deposited layer of thin cellulose fibers formed in the mold of the mold captures the fine particles of the ceramic raw material composition when draining the ceramic raw material composition, and the fine particles form the flow channel of the mold. to prevent it from becoming clogged. To form such a thin deposited layer of cellulose fibers, an aqueous paper solution prepared by dissolving water-soluble paper such as Japanese paper, toilet paper, and dust paper in water is generally used. The deposited layer is formed, for example, by uniformly applying the aqueous solution inside the mold, draining it by vacuum suction from the back of the mold, and then drying it. In particular, when considering the adhesion of the cellulose fiber deposited layer to the inner surface of the mold, good results are obtained when the cellulose fiber deposited layer is in a semi-dry state. Note that the cellulose fibers forming the cellulose fiber deposit layer are not limited to Japanese paper and toilet paper as described above, and any cellulose fiber material can be used as long as it is water-soluble. . In this case, if the deposited layer of cellulose fibers is too thin, the effect of trapping the particulate raw material will be reduced, and if it is too thick, the drainage properties of the ceramic raw material composition will be impaired. Taking these into consideration, we can reduce the thickness to 50
It is preferable to set the thickness to ~300 μm. The most desirable thickness is around 100 μm.

In particular, forming a thin filter layer made of cellulose fiber inside the mold by the method described above can be used as the water-permeable dish-shaped mold to produce ceramics with a three-dimensional pattern that has an uneven pattern on the bottom surface. Good results are obtained when using molds for plate production. In other words, the above-mentioned mold is used to manufacture tiles, etc. that have a three-dimensional pattern formed on the surface, but the internal bottom surface has an uneven pattern for transferring and forming the three-dimensional pattern on the tile, etc. has been
For example, even if a sheet-like filter film is placed in a mold with such an uneven pattern, wrinkles will occur in the uneven pattern, and it is difficult to form a uniform filter film along the uneven pattern. I can't. However, if an aqueous solution of cellulose fibers is put into a mold, drained, and dried to form a deposited layer of cellulose fibers as in the present invention, the deposited layer formed will have an uneven pattern on the bottom of the mold. It is now formed with a uniform thickness along the . Therefore, a cellulose fiber filter thin layer of good performance can be formed with a uniform thickness without causing problems such as wrinkles, and this is a major feature of the present invention. In addition, even when manufacturing large tiles (450 mm square) instead of the conventional small tiles, it is possible to easily form a thin layer of filter with a uniform thickness throughout the inside of the mold. Particularly excellent effects can be obtained when applied to the production of tiles that are large in size and have three-dimensional patterns as described above.

Then, a clay-like ceramic raw material composition is placed in a water-permeable dish-shaped mold in which a deposited layer of cellulose fibers as described above is formed, and water is drained to form a molded product. Draining in this case is usually carried out by forcibly draining the moisture in the ceramic raw material composition to the outside through the passageway of the mold by applying vacuum from the back side of the mold. the result,
A molded article made of the solid component of the ceramic raw material composition is formed in the mold. The molded product thus formed is removed from the mold by suction with a suction cup or the like. In this case, the molded product is integrated with a deposited layer of cellulose fibers provided inside the mold, and is removed from the mold together with the molded product at the time of demolding.

Next, the molded article demolded as described above is subjected to generally known drying and firing treatments corresponding to the physical properties of the raw material composition.

In this way, the molded product is fired and turned into a ceramic plate such as a tile, but the deposited layer of cellulose fibers integrated with the molded product protects it from rapid evaporation and dehydration from the surface during drying. This prevents cracks from forming even during rapid drying, and it burns and disappears during the firing process, so ceramic plates can be manufactured without the need for complicated processes such as peeling off the filter film. This also greatly contributes to shortening the manufacturing process.

In this way, the desired ceramic plate is obtained.

〔Effect of the invention〕

As described above, according to the present invention, a water-permeable dish-shaped molding is used in which an aqueous solution of cellulose fibers is placed in a mold, drained, and dried to form a thin deposited layer of cellulose fibers in the mold, and this is used as a ceramic raw material. The composition is poured and drained to form a molded article, so the deposited layer of cellulose fibers acts as a filter. Therefore, the fine particles of the ceramic raw material composition are captured by the cellulose fiber deposited layer and do not clog the passageway of the water-permeable dish-shaped mold. Therefore, the draining operation can be carried out quickly, and at the same time, the deformation of the molded product due to the clogging can be eliminated, and the effect of improving manufacturing efficiency can be realized. In particular, if the above-mentioned mold has an uneven pattern formed on the bottom and a thin cellulose fiber filter layer is used on the bottom, the ceramic plate with the three-dimensional pattern can be treated as a flat ceramic plate. It can now be manufactured with similar good efficiency.

Next, examples will be described in detail.

[Example] First, a water-permeable dish-shaped mold (inner dimension is 450 mm square)
As shown in FIG.
Prepare 1 in which . Next, an aqueous Japanese paper solution was prepared using 1 to 25 g of Japanese paper and 2 to 3 parts of water, and this aqueous Japanese paper solution was uniformly applied to the entire inner surface of the water-permeable dish-shaped mold. Then, vacuum is drawn from the back side of the water-permeable dish-shaped mold (20 to 30 mm).
Hg) and drained to form a Japanese paper filter film with a thickness of about 100 μm inside the mold 1 as shown in FIG. In this case, the Japanese paper filter membrane is
It was formed to have a uniform thickness along the uneven pattern 1a on the bottom surface of the mold, and the surface of the formed filter film 2 was in a flat state without wrinkles or the like.
Then, while the filter film 2 is in a semi-dry state, as shown in the third figure, a ceramic raw material composition consisting of 40 parts by weight of a clay raw material, 55 parts by weight of a felsic powder raw material, and 5 parts by weight of talc is prepared. Sample 3 whose water content was set at about 40% by weight was poured into the mold 1. Next, the moisture in the ceramic raw material composition 3 was removed by vacuum suction from the back side of the mold 1, and a molded article was formed using the solid content of the ceramic raw material composition. Then, the formed molded article was removed from the mold together with the filter membrane by suction with a suction cup. This is shown in FIG. In FIG. 4, 3a is a molded product, and 2 is a filter membrane.
Next, this molded article 3a was dried at 300 to 500°C for 1 to 3 hours, and then placed in a firing furnace at a temperature of 1000°C or higher and fired. In this case, the drying and firing were carried out by pre-drying and pre-heating so as not to cause cracks in the molded article 3a, followed by main drying (main heating). During this drying or firing process, the filter film 3a made of Japanese paper was burned out, and the desired 450 mm square tile with a three-dimensional pattern was obtained.

In the above example, a large tile with an uneven pattern formed on the surface was manufactured, but the small (approximately 10 mm square) flat tile that has been used in the past can also be manufactured in the same manner as in the above example. In this case as well, it is possible to improve the draining speed of the mold and to prevent the molded product from collapsing during demolding.

[Brief explanation of the drawing]

1 to 4 are explanatory views of the manufacturing state of one embodiment of the present invention. 2... Water-permeable dish-shaped mold, 1a... Uneven pattern,
2... Filter film, 3... Ceramic raw material composition,
3a... Molded product.

Claims (1)

[Scope of Claims] 1. A clay-like ceramic raw material composition is placed in a water-permeable dish-shaped mold, and water is drained to form a molded article made of solid components of the ceramic raw material composition in the mold. , a method for producing a ceramic plate in which the molded product is demolded, then dried and fired to produce a ceramic plate, in which an aqueous solution of cellulose fibers is placed in the mold as the above-mentioned water-permeable dish-shaped mold, and the water is drained. A method for producing a ceramic plate characterized by using a material that is dried to form a thin deposited layer of cellulose fibers in a mold. 2. The method for manufacturing a ceramic plate according to claim 1, wherein the aqueous solution of cellulose fibers is an aqueous solution of water-soluble paper such as Japanese paper or toilet paper. 3 The thickness of the deposited layer of cellulose fibers is 50~
A method for manufacturing a ceramic plate according to claim 1 or 2, wherein the thickness is set to 300 μm. 4. A water-permeable dish-shaped body whose bottom surface has an uneven pattern for transferring a three-dimensional pattern onto the surface of a ceramic plate, and a cellulose fiber filter thin layer formed on the inner surface of this water-permeable dish-shaped body. A mold consisting of. 5. The mold according to claim 4, wherein the water-permeable dish-shaped mold body is made of gypsum.