JPS63132006A - Manufacture of pottery board and molding die used for said manufacture - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

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.

8 [Prior Art] There are two methods for producing ceramic plates such as tiles: a dry method and a wet method. The dry method uses a dry powder composition made by appropriately combining clay raw materials and felspar (feldspar, silica, etc.) consisting of fine particles, as well as raw materials such as talc, dolomite, and lime.
A ceramic plate such as a tile can be made by charging the composition into the molding recess of the mold, pressurizing the charged composition with an upper mold made of a flat mold, removing the formed body from the lower mold and firing it. This is a method of manufacturing.

In addition, in the wet method, a wet composition ( A slurry-like raw material composition) is placed in a water-permeable dish-shaped mold made of gypsum, and water in the wet composition is drained through the mold, and the solid component of the wet composition is placed in the mold. Form a molded body. Next, the molded body is removed from the mold by suction using a suction cup or the like, and after drying, the molded body is placed in a kiln and fired to produce a ceramic plate such as a tile.

[Problem that the invention seeks to solve]

Of the two types of manufacturing methods mentioned above, the dry method uses high pressure (350 k
g/cd). Therefore, when making a large product, for example 30 x 30 cm, 31st of pressure is required, and when 600 x 600 am, 1st of pressure is required.
A pressurization of 260 tons is required. As a result, the equipment becomes extremely large, and when the dry powder composition is pressed and compacted, the distribution of the powder becomes uneven, causing distortion, etc.
This method has the disadvantage that cracks and cracks occur in the molded product, resulting in an increase in the number of defective products.

In the wet method, it is sufficient to simply flow the wet composition into a water-permeable dish-shaped mold, so a large pressure is not required, and the distribution of the powder is relatively uniform. However, when draining water using a water-permeable dish-shaped mold, fine particles distributed in the wet composition are removed from the water-permeable dish-shaped water passages (gaps formed between molecules of gypsum). This causes clogging, which impairs drainage properties and takes a long time to manufacture.At the same time, the molded product obtained has a high moisture content as the number of molding increases, and when demolding, sometimes has the disadvantage of being muscular. If an attempt is made to pressurize the wet composition in order to improve such drainage, the water-permeable dish-shaped mold made of gypsum will chip or crack, making it impossible to achieve this.

In order to solve such problems, the present inventors used a sponge-like body made of rubber, synthetic resin, etc. in place of the water-permeable dish-shaped plaster mold used in the wet method, and placed the wet composition in the mold. By pressure-casting (slurry-like raw material composition) and draining water by vacuum suction from the surrounding area, a uniform powder molded body can be obtained in a short time, and when this is fired, it becomes extremely good. It has been discovered that ceramic plates can be obtained. If this is further improved, an excellent -N effect can be obtained.

The present invention was made in view of these circumstances, and it is possible to more efficiently manufacture V8 porcelain plates with uniform powder distribution and no cracks or cracks without increasing the size of the equipment. Its purpose is to provide a method for manufacturing ceramic plates and a mold for use therein.

[Means for solving problems]

In order to achieve the above object, the present invention prepares an upper mold and a lower mold, at least one of which is formed of a porous elastic body with continuous pores, and combines the two molds to close the mold. A slurry-like raw material composition is pressure cast into the molding part of at least one of a mold and a lower mold, and the raw material composition is suction-dehydrated through the continuous pores of the porous elastic body with continuous pores, and the obtained molding is performed. The first gist is a method for manufacturing a ceramic plate in which a product is demolded and turned into a ceramic plate through a firing process, and as a mold for manufacturing the above-mentioned ceramic plate, a molding part is formed on at least one mold surface. an upper mold and a lower mold, and a raw material casting means for pressure-casting a slurry-like raw material composition into the molding section when the molds are combined and closed; One of the lower molds is made of a porous elastic body with continuous pores, and the other is made of a sealing body, and the mold made of the porous elastic body with continuous pores is left with the mold surface. The second gist is a device that is hermetically housed in a mold while maintaining a void, and is provided with a suction means for vacuum suctioning the void in the mold.

That is, in the present invention, one or both of the upper mold and the lower mold are formed of a porous elastic body with continuous pores. When both the upper mold and the lower mold are not made of a porous elastic body with continuous pores, the remaining one is made of a sealing body. In particular, when one mold is made of a sealing body as described above, the structure of the device is simpler than when both the upper mold and the lower mold are made of a porous elastic material with open pores. This makes it possible to efficiently perform vacuum suction, etc. As a result, ceramic plates with uniform powder distribution and no cracks or cracks can be manufactured more efficiently.

The ceramic plate according to the present invention is produced by pressure-casting a wet composition into the molding part of the mold using the above-mentioned special upper mold and lower mold, with both molds brought together and the mold closed, followed by suction dehydration. The molded product is obtained by draining water and firing the obtained molded product. In this case, a molding part is formed on one or both of the mold surfaces of the upper mold and the lower mold, and the wet composition is pressure-molded in the molding part when the molds are brought together.

As the porous elastic body with continuous pores, a sponge-like body made of rubber or synthetic resin is used.

In this case, the sponge-like body must have continuous pores, and the effects of the present invention cannot be achieved if the sponge-like body has closed pores. That is, the continuous pores of the sponge-like body serve as water passages during suction dehydration, and the wet composition is drained through these water passages. in this case,
The pore size of the continuous pores has a great influence on drainage performance,
It is preferable that the pore diameter is set to be approximately the same as the voids between gypsum molecules in a water-permeable dish-shaped mold made of gypsum.

A mold made of such a porous elastic material with open pores is usually sealed in a mold with the mold surface left open, and the voids in the mold are vacuum-suctioned. Through the continuous pores, the wet composition pressure-cast into the molding part is suction-dehydrated.

As described above, in the mold used in the present invention, either or both of the upper mold and the lower mold are formed of a porous elastic body with continuous pores. When one side is formed of a porous elastic body with continuous pores, the other side is formed of a sealing body. In this case, the shape of the seal body does not matter, such as a plate-like body or a table-like body. When the wet composition in the molding section is sucked and dehydrated through the continuous pores of one of the molds made of the porous elastic body with continuous pores, this seal body is designed to (contact surface) so that the suction force during suction dehydration can sufficiently act on the wet composition. Therefore, if it maintains sealing properties,
It may be made of any material, and may be made of an elastic body such as dense rubber or synthetic resin;
It may be made of a rigid body such as metal.

The molding part such as the molding recess for pressure casting the slurry-like raw material composition may be formed in a mold made of the porous elastic body with continuous pores, or in a mold made of the sealing body. may be formed. Further, instead of forming it on either the upper mold or the lower mold, it may be formed on both so that the molded parts of both molds coincide with each other when the mold is closed. Furthermore, instead of providing only one molding section, a plurality of molding sections are provided on the mold surface and communicated with each other via a slurry supply path, so that a plurality of molded objects can be formed in one molding operation. may be obtained.

The wet composition (slurry-like raw material composition) to be pressure cast into the molding part as described above may include the above-mentioned clay raw material, felsic powder raw material made of silica powder, feldspar, etc.
A material obtained by kneading a conventionally known ceramic raw material such as talc by a conventionally known method and adjusting the moisture content as appropriate is used. In this case, the wet composition has a moisture content of 20 to 25
It is preferable to adjust the amount to % by weight (hereinafter abbreviated as "%"). In addition, the pressure during the pressure casting is 5 to 3
0kg/an! It is preferable to set it to . That is, by setting the moisture content and the pressure of pressure casting as described above, good water removal properties can be achieved in combination with the effect of suction dewatering.

In addition, since the wet composition is cast into the molded part under pressure, it is necessary to keep the upper mold and the lower mold together in a closed state during this casting. Pressure casting of the wet composition into the molding part of the closed mold is generally carried out by using a nozzle or the like to pressure cast the wet composition into the molding part.

As described above, in the present invention, a wet composition is pressure cast, and at that time, the pressure of pressure casting is applied to the porous elastic body with continuous pores. However, if the elastic body is deformed by this pressure and the bottom surface of the molding recess or the surface of the elastic body is deformed too much, it becomes impossible to obtain a ceramic plate of a predetermined shape. Therefore, as a porous elastic body with continuous pores, the pressure is 30 kg/co! It is preferable to set the strength to such a degree that the mold surface of the bottom elastic body of the molding recess will sink only at a rate of 0.1 or less from the initial state.

According to the present invention, one or both of the molds used are made of a porous elastic body with continuous pores. In particular, when one mold is formed of the porous elastic body with continuous pores and the other mold is formed of a sealing body, there is no need to provide a water absorption and dehydration mechanism in the sealing body, and the structure of the entire molding die is improved. It gets easier. In addition, since it is sufficient to apply suction dehydration force only to the porous elastic body with continuous pores, the suction force required during suction dehydration can also be reduced, resulting in a further improvement in manufacturing efficiency. It becomes like this.

Next, FIG. 1 shows an example of a mold in which either the upper mold or the lower mold is formed of a porous elastic body with continuous pores, and the other mold is formed of a sealing body.

FIG. 1 shows an example in which the upper mold 1 is composed of a sealing body 2 made of rubber, and the lower mold 3 is composed of a porous elastic body 4 with continuous pores made of rubber sponge. The lower mold 3 has a square plate shape, and a molding recess 5 is formed in the mold surface. Reference numeral 6 denotes a box-shaped formwork with an open top that accommodates the lower mold 3 with its mold surface (contact surface with the seal body 2) remaining, and between the bottom surface of the lower mold 3 and the bottom surface of the mold frame 6. The crosspiece 8 is placed so that a certain gap 7 is maintained between the
is installed. Numeral 9 is a bolt for tightening and assembling the formwork 6, and 10 is a vacuum suction pipe for vacuum suctioning the inside of the gap 7. A molding recess 5 is formed in the mold surface of the lower mold 3, and a pipe 13 extends into the slurry flow path 11 of the molding recess 5 from a wet composition tank 12 with the seal body 2 inserted therein. . Reference numeral 14 denotes a gasket disposed between the upper mold 1 consisting of the sealing body 2 and the mold frame 6 of the lower mold 3, which acts to seal the insides of both molds 1 and 3.

In this mold, in the mold closed state as shown in the figure, a wet composition 15 is pressure-casted from a wet composition tank 12 through a pipe 13 into a molding recess 5 of a lower mold 3, and then a vacuum suction pipe The wet composition 15 cast into the molding recess 5 through the continuous pores of the porous elastic body 4 is suctioned and dehydrated. This mold can perform suction dehydration from the bottom side of the lower mold 3, so when manufacturing large ceramic plates using a large amount of wet composition, molding can be carried out in a short time, and suction dehydration can be carried out throughout the entire body. This can be done evenly to form a uniform molded product. At that time, since the upper mold l is the sealing body 2 and the target to be vacuum-suctioned is only the lower mold 3,
There is no need to increase the degree of vacuum suction required for suction dehydration, and efficient suction dehydration can be performed. After suction dehydration in this way, upper mold 1
The mold is opened by sliding it laterally, and the molded article is taken out. Then, by drying and firing this using a conventionally known method, a ceramic plate can be manufactured.

In addition, when performing suction dehydration as described above, even if it is performed at a considerable degree of vacuum, the suction force is appropriately relaxed through the continuous pores in the porous elastic body 4 with continuous pores, and the suction force in the molding recess 5 is Added to wet composition 15. Therefore, the suction force during suction dehydration does not adversely affect the molding of the wet composition.

In particular, when producing ceramic plates by the method of the present invention, it is extremely effective for producing large ceramic plates with three-dimensional patterns formed on their surfaces. That is, according to the above method, since the molding is performed using a wet composition, the distribution of the powder becomes uniform, and since it is performed by pressure casting, it can be performed quickly. Furthermore, since suction dehydration is performed, it is possible to quickly remove water, and therefore it is possible to adequately handle large ceramic plates using a large amount of wet composition. Furthermore, since wet molding is used, by forming a concavo-convex pattern for three-dimensional pattern transfer on the bottom of the molding recess, it is possible to easily and precisely transfer and form a three-dimensional pattern on the surface of the large ceramic plate. Become.

In the above explanation, the lower mold 3 is made of a porous elastic body 4 with continuous pores, but as shown in FIG. 2, the upper mold 1 is made of a porous elastic body 4 with continuous pores, The lower mold 3 may be configured with the seal body 2. Further, as shown in FIG. 3, the lower mold 3 is composed of a porous elastic body 4 with continuous pores, the upper mold 1 is composed of a sealing body 2, and both molds 1.3 have molding recesses 5, 5' may be provided so that the molding recesses 5' and 5' meet when the mold is closed to form one molding recess 18 as a whole. In addition, as shown in Fig. 4, the lower mold 3
is composed of a porous elastic body 4 with continuous pores, and is placed in a formwork 16 having a hollow interior. Small holes 17 are formed on the inner surface of the formwork 16, and this hollow part is vacuumed. By suctioning, the entire outer peripheral surface of the porous elastic body 4 with continuous pores may be dehydrated by suction. Furthermore, in FIG. 1, the upper mold 1 is made of a porous elastic body 4 with continuous pores, similar to the lower mold 3, instead of having a seal body structure, and has a structure in which a gap 7 is formed by a crosspiece 8, and both upper and lower molds 1 It is also possible to carry out absorption and dehydration from .3 onwards. Also, Fig. 3.

Regarding the molds shown in FIG. 4, each upper mold 1 may have the same structure as each lower mold 3, and water may be suctioned and dehydrated from both the upper and lower molds 1.3.

〔Effect of the invention〕

As described above, the present invention uses a porous elastic body with continuous pores having a molded part in place of the water-permeable dish-shaped mold made of plaster in the conventional wet method, and uses this to form one or both of the upper mold and the lower mold. forming a molding part on at least one of the mold surfaces of both molds, and pressure casting a wet composition into the molding part,
Next, the continuous pores of the porous elastic body with open pores are used to perform suction dehydration to produce a molded product, so that it is possible to achieve a uniform powder distribution in the wet method and shorten the draining time. As a result, the strength is large and it cracks.

It is possible to efficiently produce ceramic plates without cracks. This is extremely effective for large ceramic plates that have uneven patterns on their surfaces.

Next, the present invention will be explained in detail based on examples.

[Example 1] First, a mold as shown in FIG. 1 was prepared as a mold. Next, 40 parts by weight of clay raw material (hereinafter abbreviated as "parts") and 55 parts of felsic powder raw material.

A ceramic raw material composition 15 consisting of 5 parts of talc and having a water content of about 20% was poured from the tank 12 into the molding recess 5 of the lower mold 3 at a pressure of 20 kg/-. Next, vacuum suction is performed to remove 50% of the above composition 15.
After draining for a minute, the obtained molded body was demolded. After drying this molded body at 300 to 500°C for 1 to 3 hours, it was fired in a firing furnace at a temperature of 1000°C or higher. In this case, the drying and firing were carried out by pre-drying and pre-heating so as not to cause cracks in the compact, followed by main drying and heating. The tiles thus obtained are 300 x 300
It had a large size of x 10 ml, was beautiful with a three-dimensional pattern formed on its surface, had no cracks or cracks, and was extremely strong.

[Example 2] A mold shown in FIG. 4 was used in place of the mold shown in FIG. 1. The rest was the same as in Example 1.

The mold shown in FIG. 4 has an inner container 17a provided inside the lower mold 3, a large number of small holes 17 in the inner container 17a, and a porous elastic body 4 accommodated in the inner container 17a. Inner container 1
Vacuum suction is performed from the gap 16' between the porous elastic body 4 and the porous elastic body 4, and vacuum suction can be performed from the entire side and bottom surface of the porous elastic body 4. therefore,
In Example 2, the draining time was shortened compared to Example 1.

In the above example, a large tile with an uneven pattern formed on the surface is manufactured, but the above example also manufactures a small (about 10 dragon squares) flat tile that has been used conventionally. It can be manufactured by the same method as above, and the same effects as above can be obtained in that case as well.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of one embodiment of the mold used in the present invention, Fig. 2 is a sectional view of another embodiment, Fig. 3 is a sectional view of yet another embodiment, and Fig. 4 is a sectional view of another embodiment. FIG. 3 is an example cross-sectional view.

Claims (6)

[Claims] (1) Prepare an upper mold and a lower mold, at least one of which is formed of a porous elastic material with continuous pores, and mold at least one of the upper mold and the lower mold with the molds closed together. A slurry-like raw material composition is pressure cast into the chamber,
A ceramic plate characterized in that the raw material composition is suction-dehydrated through the continuous pores of the porous elastic body with continuous pores, and the obtained molded product is demolded and made into a ceramic plate through a firing process. Manufacturing method. (2) The method for manufacturing a ceramic plate according to claim 1, wherein the molding part is a molding recess, and a concave-convex pattern for transferring the concave-convex pattern is formed on the bottom surface of the concave part. (3) The method for manufacturing a ceramic plate according to claim 1 or 2, wherein the porous elastic body with continuous pores is composed of a sponge-like body made of rubber or synthetic resin. (4) The moisture content of the slurry-like raw material composition is 20 to 25
A method for manufacturing a ceramic plate according to any one of claims 1 to 3, wherein the content is set to % by weight. (5) Pressure casting of slurry-like raw material composition
A method for manufacturing a ceramic plate according to any one of claims 1 to 4, which is carried out at a pressure of kg/cm^2. (6) An upper mold and a lower mold each having a molding part formed on at least one mold surface, and a slurry-like raw material composition being pressure-injected into the molding part when the molds are closed together. A raw material casting means for molding is provided, one of the upper mold and the lower mold is composed of a porous elastic body with continuous pores, and the other is composed of a sealing body, and the porous elastic body with continuous pores is A forming mold characterized in that the constructed mold is hermetically housed in a mold while maintaining a void with the mold surface remaining, and is provided with suction means for vacuum suctioning the void in the mold.