JPH11105025A - Base molding mold and production of base using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a base molding mold that provides a good base release properties, which can perform continuous molding and which can produce a molded article having highly accurate shape and dimensions. SOLUTION: This base molding mold is obtained by thermosetting a press molded piece obtained by mixing together 56 parts by weight of alumina powder having a grain size of #240, 30 parts by weight of calcium carbonate which is treated with silicone for surface water repellency, 0.5 parts by weight of glass-fiber chips (length and diameter of each fiber are 3 mm and 9 μm, respectively) from a bundle of 200 fibers, 7 parts by weight of phenole resin, 7 parts by weight of hardening agent and 7 parts by weight of silicone powder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for manufacturing ceramics, and more particularly, to a mold for forming a base (molding clay having plasticity), and a base using the mold. And a method for molding the same. Ceramics can be manufactured by drying and firing the molded body obtained by the molding method. The mold includes various molds such as a trowel mold and a mold for high-pressure casting, and also includes a mold having air permeability.

[0002]

2. Description of the Related Art Conventionally, as a mold for molding a base or a method of forming a base using such a mold, for example, Japanese Patent Publication No. Hei 3-19041, Japanese Patent Publication No. Hei 7-319
No. 56, Japanese Patent Laid-Open No. 54-16518, Japanese Patent Publication No. 5
JP-A-6-14451, JP-A-58-65609, JP-A-60-89303, JP-A-61-15
There is a technique described in JP-A-2738, JP-A-61-154808, or JP-A-61-277409.

[0003]

Conventionally, in a rotary iron-roll rolling method, a metal material is used as a trowel material, gypsum is used as a receiving mold (a receiving mold in wheel casting), and the iron material is heated. By forming a film of water vapor between the iron and the forming clay (base) during the forming (during the rotary molding), it is possible to prevent the adhesion between the kneaded clay and the iron to be contact-rolled at the time of forming and to prevent the adhesion between the kneaded clay and the iron material. A heating iron method has been used in which molding is performed while keeping the contact of the coating smooth. In this heating iron method, the surface temperature of the iron material is usually 95
C. to 105.degree. C. is appropriate, and if it is lower than this, the clay adheres to the iron, and if it is higher than this, cracks occur on the back surface of the molded product. For this reason, it is necessary to maintain the above-mentioned temperature at a constant temperature, and the operation of constantly maintaining the temperature at a constant temperature requires skill, which is a molding method that is difficult to control.

Further, when the iron is kept in a heated state, heat is transmitted to the mounting member (for example, lever or rod) of the iron, and the position between the mold and the iron is affected by the thermal expansion caused by heating of each mounting member. This causes an error in the rotation axis between the mold and the iron due to the displacement. As a result, there has been a problem that a change in the thickness of the molded product is inevitable and the accuracy of the shape of the molded product is deteriorated.

[0005] As a prior art for solving this problem, Japanese Patent Publication No. 3-19041 discloses a method of roto-rotational rolling and molding of pottery crockery and a rotary molding iron.
Japanese Patent Publication No. 3-19041 discloses a method for manufacturing a gas permeable resin iron.
To form a thin gas film between the kneaded clay and the iron while performing rotary rolling molding. However, when these iron molds are used, there is a problem that the mold separation from the metal base is poor due to the sticking of the iron mold and the green body, which hinders practical use because it cannot be continuously molded. Was.

[0006] Further, a method of using a gypsum mold as a molding die used for cast molding of ceramics is generally used. In molding using a gypsum mold, when clay is contained in the molding base, Na ions in the clay and Ca ions in the gypsum mold perform ion exchange to aggregate the base particles. Since the molded product is easily released from the mold, there is no problem that the mold release from the substrate is poor as described above. However, once the molding is completed, the molding gypsum mold needs to be dried. Drying may be done by natural drying,
Usually, forced drying using hot air at a relatively low temperature lower than the decomposition temperature of gypsum is performed. Since such a drying step is required, it is not possible to continuously mold with a single mold. Therefore, when a large number of ceramics are manufactured at the same time, a large number of gypsum molds are required. Therefore, there is a problem that it is difficult to mass-produce (especially, it is difficult to rapidly produce a large amount of porcelain), and it takes time and cost to manufacture a gypsum mold. The same applies to bowl molding.

[0007] A mold having an air-permeable porous structure obtained by heating and solidifying a mixture of a synthetic resin and an inorganic compound powder does not require the above-mentioned drying step as in the case of using a plaster mold, and the workability of the mold is reduced. It is very excellent in terms of abrasion resistance, heat resistance, water resistance, etc., and is particularly suitable as a gas-permeable mold (for example, a trowel mold or a molding mold) because the pore diameter inside the mold is easily controlled. As a prior art relating to such a mold having an air-permeable porous structure obtained by heating and solidifying a mixture of a synthetic resin and an inorganic compound powder and a molding method using the mold, Japanese Patent Application Laid-Open No. Sho 54-16518 is disclosed. No. 56-14451, a method for forming an inorganic material disclosed in JP-A-58-65609, and a ceramic disclosed in JP-A-60-89303. High pressure cast molding method for material
No. 738, a plastic vacuum forming mold, a method of water-based wet forming of a ceramic disclosed in Japanese Patent Application Laid-Open No. 61-154808, a method of molding and demolding ceramics disclosed in Japanese Patent Application Laid-Open No. 61-277409, and an apparatus therefor are known. ing.

However, even when molding is performed using these molds, there is a problem that the mold is separated from the base due to sticking between the mold and the base, and various measures have been taken. The problem of poor mold separation has not been sufficiently solved. Therefore, it was not possible to continuously mold using the same mold. For example, JP-A-61
JP-A-154808 describes that a releasing action is smoothly performed on an oil film on the surface of a mold by covering the surface of particles constituting the mold with non-water-impregnated oil. Tokiko 56-14
No. 451 discloses that a slightly water-soluble divalent cation inorganic compound powder for aggregating base particles into a molded product mold composition has a weight ratio of 5%.
It has been proposed that the releasing action is smoothly performed by containing the content of about 15%. However, even with these known methods, there was a problem that the releasability between the substrate and the used mold was still insufficient.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and to provide a mold for forming a base which has good mold separation from the base. It is another object of the present invention to provide a base forming mold that can be continuously formed, and a base forming mold that can obtain a formed body having high shape and dimensional accuracy. Next, it is an object of the present invention to provide a method of forming a base, which has good mold release from the base. It is another object of the present invention to provide a green body forming method which can easily perform molding without requiring temperature control in a narrow temperature range during molding.

[0010]

Means for Solving the Problems The present inventors diligently provide means for making the molding surface of a molding die hydrophobic, since if the molding die is hydrophilic, the mold is not easily separated from the substrate due to sticking to the substrate. As a result of the study, it was found that water-repellent powder particles having at least a surface exhibiting water repellency (for example, at least one of silicone resin powder particles and water-repellent calcium carbonate powder particles)
Seed) as at least a part of the filler, wherein the water-repellent powder is such that a hydrophilic molding surface (eg, a phenolic resin molding surface) is sufficiently hydrophobic for mold release. The substrate was molded using a substrate molding die that exposed body particles to the molding surface (particularly, a substrate or a mold that supplies gas to the interface between the substrate to be molded and the molding surface of the mold). However, it has been found that this mold for forming a base has a good mold release from the base or the formed body during forming and can be continuously formed, and has completed the present invention.

According to a first aspect of the present invention, there is provided a resin mold containing water-repellent powder particles having at least a surface exhibiting water repellency as at least a part of a filler, and having a molding surface sufficient for mold release. The above object can be achieved by a base molding die in which the water-repellent powder particles are exposed to the molding surface to such an extent that the particles become hydrophobic. This base forming die can be in the following mode.

The resin mold may be a trowel or a mold for supplying gas to an interface between a base to be molded or a molded body and a molding surface of the mold. A phenol resin may be contained as the resin type resin. The water-repellent powder particles may be at least one of silicone powder particles and inorganic powder particles whose surface has been subjected to a water-repellent treatment. The water-repellent inorganic powder particles can be water-repellent calcium carbonate powder particles.

[0013] One or more of corundum, silica sand, zincon and zirconia may be contained as a main component of the filler. Inorganic fibers can be included as part of the filler. The weight ratio A / B of the weight A of the resin type resin to the weight B of the water-repellent powder particles is preferably 3
/ 10 to 5/10 are good. The weight ratio A / C of the weight A of the resin-type resin to the weight C of the main component of the filler is described.
Is preferably 2/10 to 4/10.

According to a second aspect of the present invention, the above object can be achieved by a green body forming method including a forming step of forming a green body using the green body forming mold of the present invention.

In the present invention, the description of the numerical range is as follows:
It shall include not only the end values but also any arbitrary intermediate values contained therein.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION

[Base Mold] The base mold of the present invention is a resin mold containing water-repellent powder particles having at least a surface exhibiting water repellency as at least a part of the filler. Further, in the base molding die of the present invention, the water-repellent powder particles are exposed to the molding surface to such an extent that the molding surface becomes sufficiently hydrophobic for mold release. The water-repellent powder particles do not need to be uniformly dispersed in the base molding die, but are distributed more on the molding surface of the mold or in the vicinity thereof to such an extent that the effects of the present invention can be achieved. Can be reduced. However, the water-repellent powder particles are spread over the entire surface of the substrate forming mold at the same concentration (density) as that at or near the molding surface of the mold capable of achieving the effects of the present invention so that it can be easily manufactured. It can be uniformly dispersed.

When the water-repellent powder particles are uniformly dispersed in the base molding die, the weight ratio A / B of the weight A of the resin of the resin mold to the weight B of the water-repellent powder particles is preferably 3
/ 10-10 / 5/10 (more preferably 3.5 / 10-4.
5/10). Further, only the molding surface of the mold or its vicinity can be made the same as the weight ratio A / B.

The resin mold is preferably a trowel mold or a mold for supplying gas to the interface between the substrate or the molded body and the molding surface of the mold. That is, the resin mold can be provided with a gas supply hole so that gas can be supplied to an interface between the base to be molded or the molded body and the molding surface of the mold. As such a resin mold, for example, a porous resin mold (for example, a hole that is opened in a molding surface and supplies gas (preferably, a plurality of fine pores, for example, having a pore diameter of 5 to 15).
Porous resin molds having pores of about μm) and non-porous resin molds having holes formed on the molding surface to supply gas.

The mold for forming a base of the present invention can be a mold for various uses, for example, a mold for various uses such as a iron mold and a high-pressure casting mold.

[Water-repellent powder particles] The water-repellent powder particles may be those having at least a part or all of the surface exhibiting water repellency. The inside of the water-repellent powder particles does not need to exhibit water repellency, but a material exhibiting water repellency can be used. Such water-repellent powder particles can be used as part or all of the filler (preferably 20 to 60% by weight, more preferably 30 to 40% by weight of the total weight of the filler).

The water-repellent powder particles are preferably at least one of inorganic powder particles and silicone powder particles whose surfaces have been subjected to a water-repellent treatment. When the inorganic powder particles and the silicone powder particles whose surfaces are water repellent are used in combination, the weight ratio R1 / R2 of the weight R1 of the inorganic powder particles whose surface is water repellent and the weight R2 of the silicone powder particles is preferably Is 10-100
(More preferably 30 to 50).

<Inorganic Powder Particles with Water-Repellent Surface> The inorganic powder particles with a water-repellent surface are preferably calcium carbonate powder particles with a water-repellent treatment. The average particle diameter of the inorganic powder particles whose surfaces are water-repellent is preferably 0.8 to 7
μm (more preferably 1.5 to 5.0 μm).

The water-repellent inorganic powder particles such as calcium carbonate are inorganic powder particles whose surface is partially or entirely coated with a water-repellent agent (including a water- and oil-repellent agent) such as silicone.
As the water repellent (including the water repellent and oil repellent), preferably, silicone oil, fatty acid, resin acid, sulfonic acid type water repellent, polyacrylic acid type water repellent, or the like can be used.

The water-repellent inorganic powder particles such as calcium carbonate are preferably produced by the following production method. For example, white sugar limestone is wet-pulverized, classified, subjected to a surface treatment (coating treatment) with a water repellent, dehydrated, dried, and finished.

As the inorganic powder particles such as calcium carbonate subjected to the water-repellent treatment, commercially available products can be used. For example,
Maruo Calcium Co., Ltd. Snow Light SSS, Maruo Calcium Co., Ltd. Esmic, Maruo Calcium Co., Ltd.
MC coats P10 to P23 can be used.

<Silicone Powder Particles> Silicone powder particles are obtained by converting silicone resin into powder particles. The average particle diameter of the silicone powder particles is preferably 10 to 2
50 μm.

As the silicone resin, preferably, a silicone rubber elastic material obtained by pulverizing a silicone resin can be used. A commercially available product can be used as the silicone resin. For example, “Trefoil E850” manufactured by Dow Corning Toray Silicone Co., Ltd. can be used.

[Filler other than Water Repellent Powder Particles] <Powder Particles> As the filler other than the water repellent powder particles, various inorganic powder particles or organic powder particles can be used. As the filler other than the water-repellent powder particles, one or more of corundum, silica sand, zincon, and zirconia are preferably used, and more preferably, one or more of these are used as the main component of the filler (filling). Preferably 8 of the total weight of the material
0 to 40% by weight, more preferably 70 to 60% by weight).

<Inorganic Fiber> As a filler other than the water-repellent powder particles, a fibrous filler such as an inorganic fiber (including a glass fiber) can be contained. At least one of the fillers of the inorganic fibers is used as a part of the filler other than the water-repellent powder particles (preferably 0.1% of the total weight of the filler).
2 to 10% by weight, more preferably 0.5 to 2% by weight).

The filler of inorganic fibers (especially glass fibers) can improve the strength of the mold. That is, by adding a filler of inorganic fibers (especially glass fibers),
Since the modulus of elasticity can be made high, the mold for green body formation has high strength. In particular, when high pressure is required during molding (for example, iron molding) such as a bowl or the like, inorganic fibers (particularly glass fibers) can be added as a filler to reinforce the strength of the mold. .

The filler of the inorganic fiber can be used together with at least one of various kinds of inorganic powder particles and organic powder particles. The length of the fiber is preferably 3 to 12 μm
(More preferably 3 μm). The fiber diameter is preferably 5 to 24 μm (more preferably 8 to 15 μm).

Examples of the glass fibers include glass fibers made of glass such as borosilicate glass, glass containing high silica, aluminosilicate glass, and alkali-free glass.

[Resin-type resin] As the resin-type resin,
Preferably, a hydrophilic resin can be used. As for the degree of hydrophilicity, a resin having the same level of hydrophilicity as the phenol resin can be used. It is preferable to use a phenol resin as a part or all (preferably at least 80% by weight, more preferably 90% by weight, and most preferably 100% by weight) of the resin type resin. it can.

[Method of Manufacturing Base Mold] The base mold according to the present invention is, for example, a method in which a mixture obtained by uniformly mixing a resin, a filler and a curing agent for the resin is filled in a molding die. And pressurized. In the case of thermosetting resin,
It can be manufactured by heating and curing the molded body obtained by pressing. The content of each component in the mixture, molding conditions for obtaining a molded article (press pressure, etc.), and heat curing conditions for the molded article in the case of a thermosetting resin (heating rate, holding temperature, holding time at the holding temperature) , Cooling rate, etc.)
Can be appropriately set according to the type of resin used.

The preferred conditions when using a thermosetting phenol resin as the resin are as follows. The pressing pressure for obtaining a molded body is preferably 500 × 10 ^{4 to} 3
000 × 10 ⁴ Pa (more preferably 800 × 10 ⁴ to 1
500 × 10 ⁴ Pa). The heating rate of the molded article under the heat-curing conditions is preferably 15 to 30 ° C / hour (more preferably 20 to 25 ° C / hour), the holding temperature is preferably 180 to 200 ° C, and the holding time at the holding temperature is Preferably, it is 1 to 3 hours, and the temperature lowering rate is preferably 10 to 40 ° C / hour (more preferably 20 to 30 ° C).
/ Hour).

The molded article obtained by molding (in the case of a thermosetting resin, a molded article after thermosetting) can be used as a mold as it is, and further, through a processing step of processing into an arbitrary shape, becomes a mold. Can be used.

[Base forming method] The base forming method of the present invention includes a forming step of forming a base using the base forming mold of the present invention. When forming the base, various water repellents or water / oil repellents can be applied to the molding surface of the mold for forming a base of the present invention. The various water repellents or water repellents are preferably solvents (preferably organic solvents such as alcohols).
Can be applied to the substrate forming mold of the present invention in a state of being dissolved in
(At 200 ° C. for about 30 minutes to 2 hours).

[Molded Body] The shaped body obtained by the green body forming method of the present invention can have any shape and size according to the shape of the green body forming die of the present invention. For example, plates, bowls,
It can be an elliptical dish, cup, etc.

[Manufacturing method of ceramics] Ceramics can be obtained by a manufacturing method including a firing step of firing a molded article formed by using the green body forming mold of the present invention. In this method of manufacturing a ceramic, a drying step of drying a molded article formed using the green body forming mold of the present invention can be provided before the firing step. The conditions for drying and firing the green body can be appropriately set according to the type of the green body.

[0040]

【Example】

[Example 1] <filler (filler, hereinafter the same) as the main material corundum (Al ₂ O ₃₎ (alpha-alumina) with鏝型, and high-pressure casting molds> inorganic filler (particle size # 240 A mixture of 56 parts by weight of alumina, 30 parts by weight of calcium carbonate subjected to water repellency treatment on a silicone surface having an average particle diameter of 7 μm, 7 parts by weight of a synthetic resin (thermosetting phenol resin), and 7 parts by weight of a curing agent for the resin. The mixture was adjusted to obtain an adjusted material. 9 kg of this adjusted material is used for pressing 21 c in diameter.
m after filling into a dish-shaped mold with a pressure of 120 kg / c
Press molding was performed at m ² (1176.8 × 10 ⁴ Pa) to obtain a phenol resin molded product. Next, the phenolic resin molded article was heat-cured according to a heat-curing schedule of a heating rate of 25 ° C./hour, a holding temperature and a holding time at 180 ° C. for 1.5 hours, and a cooling speed of 25 ° C./hour.
The heat-cured phenolic resin molded article has air permeability.

Heat-cured phenolic resin molded product (iron type)
Was processed into a dish shape with a diameter of 21 cm to produce a permeable iron mold of synthetic resin. Using this air-permeable synthetic resin iron mold,
Inorganic material (35% clay, 23% feldspar, 20% silica, water 2
2%, where% indicates wt%) and the air supply pressure.
It was rotomolded at 5 kgf / cm ² (34.3 × 10 ⁴ Pa). At the time of iron molding (at the time of molding using the iron mold), phenomena such as sticking between the iron mold and the material (material to be molded) were not observed, and continuous molding of 10,000 times or more was possible. After molding the obtained iron molded product (the molded product obtained using the iron mold), 6
After drying at 0 ° C. for 1 hour and calcining, no defect was observed.

Further, the heat-cured phenolic resin molded article was finished into a dish shape having a diameter of 21 cm to produce a high-pressure casting mold made of a breathable synthetic resin. Using this casting mold, a casting inorganic material (clay 27%, feldspar 23%, silica stone 20%, water 30%, where% represents% by weight) is applied at a pressure of 40 kg / cm ² (1176.8 × 10 ^4). P
a), when high-pressure casting was performed under high-pressure molding conditions with a holding time of 2.0 minutes, molding was possible without any phenomenon such as sticking between the molding die and the material after high-pressure molding. The resulting high-pressure cast product was dried at a temperature of 80 ° C. for 1 hour and fired after molding, but no defects were found.

[Example 2] <Iron type using corundum (Al ₂ O ₃ ) as main material of filler> Inorganic filler (alumina having a particle size of # 240
6 parts by weight, 30 parts by weight of a surface-repellent calcium carbonate having an average particle diameter of 7 μm), 7 parts by weight of a synthetic resin (thermosetting phenol resin), and a curing agent 7 of the resin
Parts by weight and 7 parts by weight of silicone powder (Trefle E850 manufactured by Dow Corning Toray Silicone Co., Ltd.) were further mixed and adjusted to obtain an adjusted material.

After 9 kg of the adjusted material thus obtained was filled in a press dish-shaped (diameter: 21 cm) mold, the pressure was reduced to 1 kg.
Press molding was performed at 20 kg / cm ² . Next, the phenolic resin molded body obtained by press molding was thermally cured according to the same thermal curing schedule as in Example 1. Heat-cured phenolic resin molded article (trowel type) having air permeability of 21 cm in diameter
The shape of the dish was finished to produce a porcelain synthetic resin iron mold. Using this iron mold, when performing the rotary molding under the same conditions as in Example 1, no phenomenon such as sticking between the iron mold and the material was observed at the time of iron molding, and continuous molding of 10,000 times or more was possible. The mold releasability was better than that of Example 1. The obtained iron-molded article was dried at 60 ° C. for 1 hour and fired after molding, but no defects were found.

Example 3 <Iron type using corundum (Al ₂ O ₃ ) as main material of filler> Inorganic filler (alumina 56 having a particle size of # 240)
100 parts by weight of a filler composition composed of 30 parts by weight of a calcium carbonate having an average particle diameter of 7 μm and a silicone surface having water repellency were added to 200 bundles of glass fiber chips (each glass fiber was 3 mm in length and 3 mm in diameter. Is mixed with 0.5 parts by weight of a resin), 7 parts by weight of a synthetic resin (thermosetting phenol resin), 7 parts by weight of a curing agent for the resin, and 7 parts by weight of silicone powder (Trefil E850). The mixture was adjusted by mixing to obtain an adjusted material. After filling 3 kg of the obtained adjusted material into a bowl-shaped mold having a diameter of 8 cm for pressing, a pressure of 120 kg / cm ² (117
Press molding was performed at 6.8 × 10 ⁴ Pa). Next, the phenolic resin molded article was thermally cured according to the same thermal curing schedule as in Example 1.

A heat-cured phenolic resin molded article (iron type) having air permeability is finished into a bowl shape having a diameter of 8 cm,
A permeable synthetic resin trowel mold was produced. When this iron mold was used for rotomolding under the same conditions as in Example 1, no phenomenon such as sticking between the iron mold and the molding material was observed at the time of iron molding, and continuous molding of 10,000 times or more was possible. . Example 1
Than was better. Further, a pressure several times higher than the pressure applied during the rotary molding was applied to the resin mold, but no damage to the resin mold was observed. Then, after molding the iron molded product,
For 1 hour and calcined, but no defects were observed.

Example 4 <Iron type using corundum (Al ₂ O ₃ ) as a filler material> Inorganic filler (alumina 5 having a particle size of # 240)
6 parts by weight, 30 parts by weight of a surface-repellent calcium carbonate having a silicone particle having an average particle diameter of 7 μm), 7 parts by weight of a synthetic resin (thermosetting phenolic resin), 7 parts by weight of a curing agent of the resin, and silicone powder ( Trefill E850) 7
The parts by weight were mixed and adjusted to obtain an adjusted material. 9 kg of this adjusted material is dished for press (diameter 21 cm)
After filling on a mold, a pressure of 120 kg / cm ² (11
76.8 × 10 ⁴ Pa). Next, the phenolic resin molded article was thermally cured according to the same thermal curing schedule as in Example 1.

The heat-cured phenolic resin molded article (trowel type) having air permeability was finished into a dish shape having a diameter of 21 cm to prepare a gas-permeable synthetic resin iron mold. An ethanol solution containing 10% of a silicone water repellent is applied on the surface (including the molding surface) of the formed phenolic resin molded product (iron type),
It was kept at 150 ° C. for 1 hour and dried. Using the surface-treated iron mold, press iron molding was performed under the same conditions as in Example 1, and no phenomenon such as sticking between the iron mold and the pressed material was observed during iron molding, and the continuous operation was performed 10,000 times or more. Molding was possible. The mold release was better than Examples 2 and 3. The trowel molded product was dried at 60 ° C. for 1 hour and fired after molding, but no defects were found.

[0049] [Comparative Example 1] <鏝型with corundum (Al ₂ O ₃₎ as a main material of the filler, the high-pressure casting mold> inorganic filler (particle size # 2
40 parts by weight of alumina, 30 parts by weight of calcium carbonate having an average particle diameter of 7 μm), 7 parts by weight of a synthetic resin (thermosetting phenol resin), and 7 parts by weight of a curing agent of the resin. A conditioned material was obtained. 9 kg of the obtained adjusted material is dished for pressing (diameter 21 cm).
After filling on a mold, a pressure of 120 kg / cm ² (11
76.8 × 10 ⁴ Pa). Next, 2
The phenolic resin molded article was heat-cured according to a heat-curing schedule of 5 ° C./hour, a holding temperature and a holding time of 180 ° C. for 1.5 hours, and a cooling speed of 25 ° C./hour.

A heat-cured phenolic resin molded article (trowel type) having air permeability was finished into a dish shape having a diameter of 21 cm to produce a gas-permeable synthetic resin iron mold. Using this mortar type,
Inorganic material (35% clay, 23% feldspar, 20% silica, water 2
2%, where% indicates weight%), was subjected to roto-molding under the iron-forming conditions of an air supply pressure of 3.5 kgf / cm ² (34.3 × 10 ⁴ Pa). And continuous molding was difficult.

The heat-cured phenolic resin molded article was finished into a dish shape having a diameter of 21 cm to produce a high-pressure mold for air-permeable synthetic resin. Using this mold, inorganic materials (clay 27%, feldspar 23%, silica stone 20%,
Water 30%, where% indicates weight%), pressure 40 kg
/ Cm ² (392.3 × 10 ⁴ Pa) and a holding time of 2.0 minutes were subjected to high pressure casting under the iron molding conditions. However, at the time of molding, the iron mold and the press material were stuck and molding was difficult. .

[Comparative Example 2] A silicone water repellent 1 was formed on the surface of the phenolic resin molded article (mold) prepared in Comparative Example 1.
A 0% -containing ethanol solution was applied and dried at 150 ° C. for 1 hour. Using the surface-treated iron mold,
Rotary molding was performed under the same conditions as in Comparative Example 1. However, at the time of molding, sticking between the iron mold and the material to be molded was observed, making continuous molding difficult.

Comparative Example 3 An industrial oil was applied on the surface of the phenolic resin molded product (iron type) produced in Comparative Example 1 for the purpose of water repellency, and was left at room temperature for 48 hours and dried. Using the surface-treated iron mold, wheel casting was performed under the same conditions as in Comparative Example 1, but the iron mold and the material to be molded were stuck during molding, and molding was difficult.

[0054]

According to a first aspect of the present invention, there is provided a mold for forming a base material, wherein at least a surface of the mold contains water-repellent powder particles exhibiting water repellency as at least a part of a filler, and a molding surface is released. Since the water-repellent powder particles are exposed to the molding surface to such an extent that they become sufficiently hydrophobic, the following basic effects can be obtained.

(1) The mold release from the substrate or the molded body during molding is good, and molding can be performed continuously. Therefore, in particular, a molding method using a mold (for example, a trowel mold or a mold) that supplies gas to the interface between the substrate to be molded or the molded body and the molding surface of the mold can be put to practical use. (2) There is no need to provide a drying step for drying, and since the molding can be performed continuously from this point, a large amount of molded articles can be obtained quickly. In addition, since it is not necessary to prepare a large number of molds even when mass-producing the molded body, a large number of molded bodies can be produced without spending the cost and time for producing an extra mold. (3) It is possible to obtain a molded body having high shape and dimensional accuracy.

Since the base forming molds according to the second to seventh aspects further include the above-described respective structures in addition to the above-described structures, the above-described basic effects are remarkable.

The green body forming method of the eighth aspect includes a forming step of forming a green body using the green body forming die of the present invention.
Molding can be easily performed without requiring temperature control to a narrow temperature range during molding, and the mold can be obtained with good mold release from the substrate or the molded body during molding. In addition, a large amount of molded articles can be obtained quickly. Furthermore, since it is not necessary to prepare a large number of molds even in the case of mass production of molded articles, a large number of molded articles can be obtained without spending the cost and time for manufacturing extra molds. In addition, it is possible to obtain a molded body having high shape and dimensional accuracy.

A large amount of ceramics can be rapidly manufactured by the method for manufacturing ceramics including a firing step of firing a molded body formed using the green body forming mold of the present invention. In addition, even when mass-producing porcelain, it is not necessary to prepare a large number of molds, so that a large amount of porcelain can be manufactured without spending cost and time for manufacturing extra molds. Further, it is possible to manufacture ceramics with high accuracy in shape and dimensions.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toshiro Matsui 3-36 Noritake Shinmachi, Nishi-ku, Nagoya City, Aichi Prefecture Inside Noritake Company Limited (72) Inventor Takafumi Mitsuishi 3-1-1 Noritake Shinmachi, Nishi-ku, Nagoya City, Aichi Prefecture No. 36 Noritake Company Limited

Claims (8)

[Claims] 1. A resin mold containing at least a surface of water-repellent powder particles exhibiting water repellency as at least a part of a filler, wherein the water repellency is such that a molding surface is sufficiently hydrophobic for mold release. A base molding die, wherein powder particles are exposed on a molding surface. 2. The base molding according to claim 1, wherein the resin mold is a base or a molding die for supplying a gas to a substrate to be molded or an interface between a molding and a molding surface of the mold. Type. 3. The base molding die according to claim 1, wherein a phenol resin is contained as the resin of the resin mold. 4. The water-repellent powder particles according to claim 1, wherein the water-repellent powder particles are at least one of silicone powder particles and inorganic powder particles having a water-repellent surface. The mold for forming a base described in the above. 5. The mold according to claim 1, wherein the water-repellent inorganic powder particles are water-repellent calcium carbonate powder particles. 6. The green body forming die according to claim 1, wherein one or more of corundum, silica sand, zincon, and zirconia are contained as a main component of the filler. 7. The mold for forming a green body according to claim 1, further comprising an inorganic fiber as a part of the filler. 8. A green body forming method comprising a forming step of forming a green body using the green body forming die according to any one of claims 1 to 7.