JP2534966B2 - Ceramic plate manufacturing method and molding die used for the same - Google Patents

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 plate such as a tile and a mold used for the method.

[0002]

2. Description of the Related Art There are a dry method and a wet method as a method for manufacturing a ceramic plate such as a tile. The dry method is a method in which a dry powder composition made by appropriately combining raw materials such as feldspar (feldspar, silica stone) and talc, dolomite, lime, etc., which consist of clayey raw materials and fine particles, It is a method of producing a ceramic plate such as a tile by charging the composition into a mold, pressing the composition with an upper mold composed of a flat mold, and removing the molded product from the lower mold and firing.

The wet method is the same as that used in the dry method, and a suitable combination of a feldspar raw material consisting of a clay-like raw material and fine particles and a raw material such as talc, dolomite, lime, etc. A wet composition (slurry raw material composition), which is placed in a water-permeable dish-shaped mold made of gypsum, water in the wet composition is drained through the mold, and the wet composition is placed in the mold. A molded body composed of the solid content of is formed. Next, there is a method of manufacturing a ceramic plate such as a tile by adsorbing the molded body using a suction cup or the like, removing the mold from the mold, drying it, and then placing it in a baking furnace and baking it.

[0004]

The dry method among the above-mentioned two kinds of manufacturing methods requires a large pressure (350 kg / cm ² ) to press-mold the dry powder composition to form a molded body. Therefore, when making a large product, for example, 30 x 30 cm, pressurization of 315 t is required, and 600 x 600
When it is cm, pressurization of 1260t 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., which causes cracks and cracks in the molded product, resulting in defective products. It has the drawback that

The wet method does not require a large pressure because it is sufficient to simply flow the wet composition into the water-permeable dish, and the powder distribution is relatively uniform. However, when water is drained using a water-permeable dish, fine particles distributed in the wet composition are water-permeable dish-shaped channels (voids formed between gypsum molecules). Clogged in to cause clogging, the drainability deteriorates and it takes a long time to manufacture, and at the same time, the resulting molded body has a high water content as the number of molding times increases, and at the time of demolding, In some cases, it has the drawback of collapse. If an attempt is made to pressurize the wet composition in order to improve the drainage property, the water-permeable dish-shaped mold made of gypsum is chipped or cracked, which is impossible.

The present invention has been made in view of the above circumstances, and efficiently manufactures a ceramic plate having a uniform powder distribution and free of cracks, cracks, etc., without increasing the size of the apparatus. It is an object of the present invention to provide a method for producing a ceramic plate and a molding die used therefor.

[0007]

In order to achieve the above-mentioned object, the present invention has a molding recess, and when it receives a pressure casting pressure of 30 kg / cm ² , the bottom surface of the molding recess is The upper mold body corresponding to the lower mold body provided with a porous elastic body with continuous pores having a strength that sinks only at a rate of 0.1 mm or less from the initial state, and the upper mold body corresponding to the lower mold body is covered to cover the molding concave portion. Then, the slurry-shaped raw material composition is pressure-cast into the molding concave portion, and the raw material composition is sucked and dehydrated through the continuous pores of the continuous pored porous elastic body, and the obtained molded product is demolded The first gist is the manufacturing method of a ceramic plate, which is characterized by forming a ceramic plate through a firing process, and a lower mold body having a U-shaped cross section and a U-shaped opening having a U-shaped body. -Shaped upper mold body that is detachably mounted on the lower mold body in a state of being aligned with the circular opening. First and second porosity elastic bodies with continuous pores housed in the upper mold body and the lower mold body with a gap provided between the upper mold body and the lower mold body, respectively, and the second continuous pore body A molding recess formed in the surface of the porous elastic body, a raw material casting means for pressurizing a slurry-shaped raw material composition into the molding recess when the upper die main body is mounted, and both mold bodies. a suction means for vacuum suction and mold body voids between successive pores with a porous elastic body in the intensity of the continuous pores with a porous elastic body of the lower die body, 30kg / cm ²
The second gist is a molding die in which the bottom surface of the molding concave portion is set to sink at a rate of 0.1 mm or less from the initial state when receiving the pressure casting pressure.

That is, when the present inventors use a sponge-like body made of rubber, synthetic resin or the like instead of the plaster-made water-permeable dish-shaped molding die used in the wet method, the wet composition is formed in the die. After flowing down the (slurry raw material composition), a series of studies were carried out based on the idea that the material can be drained by applying pressure. As a result, it was found that a sufficient drainage improving effect cannot be obtained by simply casting the wet composition by casting and pressurizing it. Therefore, as a result of further research, it was found that not only the wet composition was simply flowed down into the molding concave portion of the porous elastic body with continuous pores such as the sponge but also pressure casting, and draining was performed by pressurization. If vacuum suction is performed instead, the water draining property will be extremely good, and a molded product with a uniform powder distribution will be obtained in a short time. At that time, the strength of the continuous porous porous elastic body It was found that a molded body having no change in shape can be obtained by setting the value to a predetermined value, and the present invention was reached.

In the ceramic plate according to the present invention, the wet composition is pressure-molded into the molding cavity of the porous elastic body with continuous pores of the lower mold body, and then suction dehydration is performed to drain the resulting molded body. It is obtained by firing.

As the porous elastic body with continuous pores, a spongy body made of rubber or synthetic resin is used. In this case, the sponge-like body needs to have continuous pores, and the one having independent pores cannot achieve the effect of the present invention. That is, the continuous pores of the sponge-like body serve as water passages during suction dehydration, and the wet composition is drained through the water passages. In this case, the pore size of the continuous pores has a great influence on the drainage property, and the pore size is preferably set to be approximately the same as the voids between the gypsum molecules in the water-permeable dish-shaped mold made of gypsum. .

The wet composition (slurry raw material composition) to be pressure-cast into the molding concave portion of the porous elastic body with continuous pores includes the above-mentioned clayey raw material, silica powder,
A material obtained by kneading a felsic feldspar powder raw material such as feldspar or the like and a conventionally known ceramic raw material such as talc by a conventionally known method and appropriately adjusting the water content thereof is used. In this case, the wet composition is preferably adjusted to have a water content of 20 to 25% by weight (hereinafter abbreviated as “%”).
Further, the pressure during the pressure casting is preferably set to 5 to 30 kg / cm ² . That is, by setting the water content and the pressure of pressure casting as described above,
This is because, in combination with the effect of suction dewatering, good drainage properties will be exhibited.

As described above, according to the present invention, the wet composition is pressure-cast, and the pressure of the pressure casting is applied to the porous elastic body with continuous pores. However, if the bottom surface of the molding recess of the elastic body is deformed too much by this pressure, a ceramic plate having a predetermined shape cannot be obtained. Therefore, the porosity elastic body with continuous pores is set to such strength that the bottom surface of the molding recess will sink only 0.1 mm or less from the initial state when a pressure of about 30 kg / cm ^{2 is} applied. Required to do.

As described above, since the casting of the wet composition is performed by applying pressure as described above, the cast wet composition overflows in the state where the molding recess is opened. Therefore, the upper mold body is overlaid on the porous elastic body with continuous pores of the lower mold body, the molding recess is covered, and the wet composition is placed in the molding recess using a nozzle or the like. Is pressure-cast. In this case, the upper die body is provided with the same porous elastic body with continuous pores as the lower die body, and this porous elastic body is overlaid on the molding die recessed porous elastic body of the lower die body. It is preferable to do so. In this case, in the subsequent step, when performing suction dehydration, it becomes possible to perform dehydration not only from the bottom surface side of the molding concave portion but also from the upper side thereof, and the draining time can be shortened.

FIG. 1 shows an example of a mold which can be sucked and dehydrated from both the bottom side and the upper side of the molding recess. In the figure, reference numeral 1 is a lower mold body having a U-shaped cross section, which is constructed by arranging a side plate 3 around a bottom plate 2 and tightening it with bolts 4. Reference numeral 5 denotes a porous sponge made of rubber sponge housed in the lower mold body 1, which is lifted from a crosspiece 7 so that its bottom surface maintains a constant space 6 with the bottom surface of the lower mold body 1. It is in a state. Reference numeral 8 denotes a molding concave portion formed on the surface of the porous elastic body 5 with continuous pores, the bottom surface of which is a convex-concave pattern surface for transferring a three-dimensional pattern.
Reference numeral 10 denotes an upper mold body having the same structure as that of the lower mold body 1 and, like the lower mold body 1, accommodates the porous elastic body 5 with continuous pores in a state in which a space 6 is maintained between the porous elastic body 5 and the bottom surface. There is. 11
Is a wet composition tank, and the wet composition 13 is pressure-cast into the molding recess 8 through a pipe 12. Reference numeral 14 is a vacuum suction pipe, which absorbs the void 6 in the lower mold body 1 and the upper mold body 10 in a vacuum,
The wet composition 13 cast into the molding recess 8 through the continuous pores of the porous elastic body 5 with continuous pores is sucked and dehydrated from both the bottom surface side and the upper side. Reference numeral 15 denotes a packing, which is attached to the upper end surface of the side plate 3 of the lower mold body 1 and, when the mold is closed, press-contacts with the lower end surface of the side plate 3 of the upper mold body 10 to seal the insides of both mold bodies 1 and 10. To work.

In this mold, when the mold is closed as shown in the figure, the wet composition 13 is pressed into the molding recess 8 while keeping both mold bodies 1 and 10 under pressure as indicated by arrow A. After the molding, the pressure is released, the upper mold body 10 is slid laterally to open the mold, and the molded body is taken out. As described above, this mold can be sucked and dehydrated from both the bottom surface side and the top surface side of the molding recess 8, so that the molding can be shortened when manufacturing a large-sized ceramic plate using a large amount of the wet composition 13. This has the effect that it can be carried out for a period of time, and that the suction dehydration can be carried out uniformly over the whole to form a homogeneous molded body.

In the above-mentioned forming die, the upper mold body 10 is also equipped with the porous elastic body 5 having continuous pores.
It is not always necessary to mount the above-mentioned porous elastic body 5 having continuous pores on 0, but a rubber plate or the like may be mounted to cover the molding recess 8.

In the present invention, the suction and dehydration of the wet composition pressure-cast into the molding recess is carried out through the continuous pores of the porous elastic body, which is usually the same as the molding die of the above drawings. Then, vacuum suction is performed from the outer peripheral surface of the porous elastic body 5 with continuous pores to perform suction dehydration. Even if the suction dehydration in this case is performed at a considerable degree of vacuum, the suction force is appropriately relaxed through the continuous pores in the porous elastic body with continuous pores 5 to the wet composition 13 in the molding recess 8. Added. Therefore, the suction force in the suction dehydration does not adversely affect the molding of the wet composition 13.

In particular, when a ceramic plate is manufactured by the method of the present invention, it is extremely effective for manufacturing a large ceramic plate having a three-dimensional pattern formed on the surface. That is, according to the above-mentioned method, since the wet composition is used for molding, the distribution of the powder becomes uniform, and it can be carried out rapidly by pressure casting. In addition, since it is sucked and dehydrated, it is possible to drain water quickly, and thus it is possible to sufficiently cope with a large-sized ceramic plate using a large amount of wet composition. Moreover, because it is performed by wet molding,
By forming the uneven pattern for transferring the three-dimensional pattern on the bottom surface of the molding recess, it becomes possible to easily and precisely transfer and form the three-dimensional pattern on the surface of the large ceramic plate.

The molded product obtained as described above can be released from the mold by suction with a suction cup or the like. Then, the demolded molded body is subjected to conventionally known drying and firing treatments corresponding to the physical properties of the raw material composition.

The ceramic plate thus obtained has a uniform powder distribution, is free from cracks and cracks, has extremely high strength, and has a dense surface.

[0021]

As described above, according to the present invention, instead of the water-permeable plaster-made plaster mold of the conventional wet method, a porous elastic body with continuous pores having a molding concave portion is used. Since a slurry-like raw material composition for tile production is cast under pressure and then suction-dewatered to produce a molded product, it is possible to realize a uniform powder distribution in the wet method and also to shorten the draining time. It is possible to efficiently manufacture a ceramic plate that has high strength and is free from cracks and cracks. In particular, according to the present invention, a large-sized ceramic plate having an uneven pattern on the surface can be manufactured very efficiently, and further, it can be manufactured without inviting an increase in the size of the apparatus such as the dry method, and a very practical effect. large. Moreover, the use of the mold according to the present invention, in addition to the above-mentioned characteristics, further has the effect that a large-sized ceramic sheet having a uniform structure and having a shape as designed can be manufactured with good efficiency. Will be obtained.

Next, examples will be described in detail.

[0023]

EXAMPLES First, a molding die as shown in FIG. 1 was prepared as a molding die. Next, a ceramic raw material composition consisting of 40 parts by weight of the clay-based raw material, 55 parts by weight of the feldspar-based powder raw material, and 5 parts by weight of talc, the water content of which was set to about 20%, was obtained from the tank 11. It was poured into the molding recess 8 of the lower mold body 1 at a pressure of 20 kg / cm ² . Next, vacuum suction was performed to drain the above composition 13 for 5 minutes, and the obtained molded body was demolded. And this molded body is 300 ~
After drying at 500 ° C for 1 to 3 hours, 1000
It was put in a firing furnace at a temperature of ℃ or more and fired. In this case, the drying and firing were carried out by predrying and preheating so that cracks did not occur in the molded body, and subsequently performing main drying and main heating. The tile thus obtained has a large size of 300 × 300 × 10 mm, is a beautiful one with a three-dimensional pattern formed on the surface, and is extremely free from cracks and cracks. The strength was also great.

Although the forming die shown in FIG. 1 is used in the above embodiment, the forming die shown in FIG. 2 may be used instead. The molding die shown in FIG. 2 is provided with inner containers 1a and 10a inside the lower mold body 1 and the upper mold body 10, and a large number of small holes 1b and 10b are provided in the inner containers 1a and 10a. , 10a in which the porous elastic body 5 is housed, and vacuum suction is performed from the gap 6 between the inner containers 1a, 10a and the mold bodies 1, 10.
Since it is possible to perform vacuum suction from the entire side surface and bottom surface, it is possible to significantly reduce the draining time.

In the above embodiment, a large tile having an uneven pattern formed on the surface is manufactured, but a small (about 10 mm square) flat plate tile which has been conventionally used is also manufactured as described above. It can be manufactured by the same method as the embodiment, and in that case, the same effect as described above can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an example of a molding die used in the present invention.

FIG. 2 is a cross-sectional view of another example.

[Explanation of symbols]

 1 Lower Mold Main Body 2 Bottom Plate 3 Side Plate 5 Porous Elastic Body with Continuous Porosity 6 Void 7 Bar 8 Molding Recess 10 Upper Mold Main Body 11 Wet Composition Tank 13 Wet Composition 14 Vacuum Suction Pipe

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yoshihiro Yokoyama 741-44, Higashiokamoto, Kawachi-cho, Kawachi-gun, Tochigi Prefecture (56) References JP-A-63-45002 (JP, A)

Claims (6)

(57) [Claims] [Claim 1] have a molded recess, pressurization of 30kg / cm ²
When receiving the casting pressure, the bottom surface of the molding
From the state, the upper mold body corresponding to this is superposed on the lower mold body provided with the porous elastic body with continuous pores having the strength that sinks only at a rate of 0.1 mm or less, and the molding recess is covered in that state. The slurry-shaped raw material composition is pressure-cast into the molding concave portion, and the raw material composition is suction-dehydrated through the continuous pores of the continuous pored porous elastic body, and the obtained molded product is demolded. A method for manufacturing a ceramic plate, which is characterized by making a ceramic plate through a firing process. 2. The method for manufacturing a ceramic plate according to claim 1, wherein an uneven pattern for transferring the uneven pattern is formed on the bottom surface of the molding recess. 3. The method for producing a ceramic plate according to claim 1, wherein the porous elastic body with continuous pores is composed of a sponge-like body made of rubber or synthetic resin. 4. The water content of the slurry-like raw material composition is 2
The method for producing a ceramic plate according to any one of claims 1 to 3, wherein the content is set to 0 to 25% by weight. 5. The pressure casting of the raw material composition in the form of a slurry,
Claim 1 performed at a pressure of 5 to 30 kg / cm ² .
Item 8. A method for producing a ceramic plate according to any one of Items 4 to 4. 6. A lower die body having a U-shaped cross section, and a U-shaped cross-section detachably mounted on the lower die body with the U-shaped opening aligned with the U-shaped opening of the lower die body. A letter-shaped upper mold body, and first and second porous elastic bodies with continuous pores housed in the upper mold body and the lower mold body with a space provided between the mold body and the bottom surface of the mold body, respectively. A molding concave formed in the surface of the second porous elastic body with continuous pores, and a raw material pouring in which a slurry-like raw material composition is pressure-cast into the molding concave when the upper mold body is mounted. A mold means and a suction means for vacuum-sucking the gap between the mold body and the porous elastic body with continuous pores in both of the mold bodies, and the lower mold body with continuous pores.
Strength of the porous elastic body of 30kg / cm ² pressurized insufflation Pressure
When received, the bottom surface of the molding recess is 0.1 from the initial state.
Mold that is set so that it sinks only at a rate of mm or less .