JP2002283319A - Case for manufacturing mold for cast-molding slurry - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a case for manufacturing a mold for cast-molding a slurry at a low cost while improving durability of the case for cast molding the slurry and suppressing a shrinkage, a deformation and a warpage. SOLUTION: The case for manufacturing the mold for cast molding the slurry comprises a front surface resin layer, a back reinforcing material for supporting and reinforcing the resin layer, and a reinforcing frame for supporting and reinforcing the back reinforcing material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a case for producing a ceramic casting mold, and more particularly to a case for producing a ceramic molding die in which two or more split molds are combined to form a slurry casting space.

[0002]

2. Description of the Related Art Conventionally, as a material for a working case for producing a slip casting mold, there is a case made of gypsum, resin alone, metal or the like.

[0003]

However, in the case of the conventional gypsum case, the case can be easily formed in a short time.
There were the following disadvantages. 1) When casting a slurry for forming a porous body to form a slurry casting mold having continuous pores in a gypsum case,
Due to the capillary suction force of the gypsum itself, moisture in the slurry for forming a porous body was absorbed in the process of hardening the slurry for forming a porous body, and the hardened porous body was partially closed pores. For this reason, it was necessary to apply evenly a water-repellent material such as wax or vaseline to the surface until the water absorption of the gypsum completely disappeared. 2) Further, since the strength of gypsum is low, the gypsum case was damaged when the gypsum case was separated from the cured porous body after the porous body forming slurry was cured, and the gypsum case could not be used repeatedly. In addition, in the case of the method of filling the gypsum surface with a resin, there is no need to apply a water-repellent material, and although the durability is slightly improved, the surface may be turned over, cracked or chipped after several uses. It was not suitable for product numbers with high production volume.

[0004] When a case is made of resin alone,
1) The shrinkage due to the exothermic reaction of the resin, the deformation after curing, and the warpage are large, so that a critical dimensional change has occurred as a case. In addition, since the shape of the porous body directly reflects the deformation and warpage of the case, when two or more split molds are combined, a gap is generated at the mating surface between the molds, and mud causes leakage. Further, it may affect the thickness of the molded body. 2) Since the unit price of the resin is higher than that of the gypsum, the case cost may be enormous.

[0005] Although a metal case is durable, the weight of the case is significantly increased, and an enormous amount of money may be required for a mold for manufacturing the case. Further, when the shape of the molded body is corrected, it is difficult to correct the case.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to cast a slurry for forming a porous body and suppress shrinkage, deformation, and warpage when the slurry is hardened. It is an object of the present invention to provide an inexpensive and durable case for producing a slip casting mold.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problem, a working case for a slurry casting mold of the present invention comprises a surface resin layer and a back reinforcing material for supporting and reinforcing the surface resin layer. Features. The surface of the working case of the slip casting mold is made of a resin layer to improve durability, and by providing a back reinforcing material for supporting and reinforcing this resin layer, shrinkage, deformation and warpage of the surface resin layer are suppressed. It is possible to do.

Further, another working case for a slurry casting mold of the present invention comprises a surface resin layer, a back reinforcing member for supporting and reinforcing the surface resin layer, and a reinforcing frame body for supporting and reinforcing the back reinforcing member. And characterized by the following. By making the surface of the working case of the slip casting mold production mold a resin layer,
By providing a back reinforcing material for improving durability and supporting and reinforcing this resin layer, it is possible to suppress shrinkage, deformation and warpage of the surface resin layer. Further, by providing a reinforcing frame that supports and reinforces the back reinforcing layer, the strength of the back reinforcing material can be complemented, and it is possible to reliably suppress shrinkage, deformation, and warpage of the surface resin layer.

In a preferred embodiment of the present invention, the surface resin layer comprises a main component constituting material comprising at least an epoxy compound and an inorganic filler, and at least a polyamideamine or a polyamine, an acid anhydride, an imidazole derivative or a polythiol compound. A first mixture of one of the hardeners selected from the group consisting of a hardener and an inorganic filler, wherein the raw material is one or more inorganic fillers and has a weight relative to the total amount of the main material. 20 by ratio
硬化 60% by weight, and one or more inorganic fillers in the above-mentioned curing agent constituent raw material are contained so that the weight ratio to the total amount of the curing agent constituent raw material is 30３０60% by weight. The viscosity of the first mixture is 40,000 to 300,000 mP at room temperature.
In order to obtain a · s, the viscosity of the main constituent material is 3000
The viscosity of the hardener constituent raw material is preferably in the range of 50,000 to 200,000 mPa · s, and the inorganic filler in the main constituent raw material is in a weight ratio to the total amount of the main constituent raw material in order to keep the viscosity within the above range. 20 ~
60% by weight, and the amount of the inorganic filler in the raw material constituting the curing agent is 3% by weight based on the total amount of the raw material constituting the curing agent.
By containing 0 to 60% by weight, the viscosity of the first mixture can be controlled within the above-mentioned appropriate range. Metal powder (especially iron powder, aluminum powder,
A slurry for forming a porous continuous porous body made of resin constituting a slurry casting mold using a slurry casting mold manufacturing case having a surface resin layer formed by mixing a copper powder). At the time of casting, the following reaction occurred and had an adverse effect on the porous body.

[0010] The case of a porous body forming slurry exhibits alkalinity, 2Al + 2MOH → The 2MAlO ₂ + H _{2 ↑} alkali melts emanated hydrogen, aluminate (MAl
O ₂ and M ₃ AlO ₂ (M is a monovalent metal) are formed. When the slurry for forming a porous body is acidic, the iron powder generates and dissolves hydrogen by the acid. Copper powder is also dissolved by the acid.

As described above, the slurry for forming the porous body reacts with the metal powder (especially iron powder, aluminum powder, copper powder, etc.) in the surface resin layer of the case to generate salts such as aluminate and hydrogen. Generates gas. Due to the generation of hydrogen gas, the surface of the porous body after hardening is roughened, which has been a factor of lowering the strength. This foaming phenomenon due to hydrogen gas occurs until a film is formed on the case surface. Therefore, until a film is formed on the case surface, the slurry for forming a porous body is applied,
It was necessary to perform casting and react with the metal part on the case surface. Alternatively, in order to form a film on the surface of the case, it is necessary to apply a curable material such as a resin or a film forming agent. As described above, when an epoxy compound containing iron powder, aluminum powder, or the like is used as the surface resin layer of the case,
A useless process of forming a film on the surface has occurred. Further, even if a film is formed, it is necessary to form the film again by polishing the case surface.

In the slip casting, since the surface of the porous body has a direct influence on the surface state of the product, the surface state of the case is good. In addition, it reacts with the slurry for forming the porous body and adversely affects the porous body. Is an absolute requirement. Further, when the surface resin layer of the case is made of resin alone (without inorganic filler), shrinkage, deformation, and warpage increase, though the reaction does not adversely affect the porous body.

As described above, by adding an inorganic filler to an epoxy compound and a curing agent, shrinkage, deformation, and warpage can be suppressed, and at the same time, adverse effects on a porous body can be avoided. Among the inorganic fillers, some of them react with the slurry for forming a porous material as described below, but do not exert any adverse effect. For example, when aluminum oxide is used instead of aluminum powder, aluminate and water are generated.
If slurry porous formation is _{acidic; Al 2 O 3 + 3H 2} O → Al 2 (SO 4) 3 + 3H 2 When O porous body forming slurry is _{alkaline; Al 2 O 3 + 2MOH →} 2MAlO 2 + H 2 O oxide Aluminum also reacts depending on the state of the slurry for forming a porous body, but produces water instead of hydrogen as a by-product, so that there is no adverse effect on the porous body.

In a preferred embodiment of the present invention, the first mixture has a blending ratio of 1% by weight of the raw material constituting the curing agent to 0.5 to 2% by weight of the raw material constituting the main agent. By setting the mixing ratio of the main component constituting material to 1/2 to 2 times the curing agent constituting material, an appropriate cured product can be obtained without causing poor curing.

[0015] In a preferred aspect of the present invention, the thickness of the surface tree layer is 0.1 to 30 mm.
By setting the thickness to 0.1 to 30 mm, shrinkage, deformation, and warpage can be further suppressed.

In a preferred embodiment of the present invention, the viscosity of the first mixture is from 40,000 to 30,000 at room temperature.
0 mPa · s. The viscosity of the first mixture is 4
In the case of 0000 mPa · s or less, the thickness of the surface resin layer becomes uneven when the first mixture is applied to the vertical surface shape portion or the like depending on the shape of the case. In addition, 300,000 mP
In the case of more than a · s, it is difficult to apply to a complicated shape portion, and workability is remarkably deteriorated. Viscosity of the first mixture 40,000
It becomes possible to apply the film uniformly at a work pressure of up to 300,000 mPa · s.

In a preferred embodiment of the present invention, the first mixture contains an alcoholic organic solvent. In the case where the surface of the case has a complicated shape, a pin may be involved in the application of the surface resin, or the resin may not be applied uniformly and evenly. For this reason, in a complicated shape portion where the surface resin coating operation is difficult, it is possible to improve the workability by adding an alcohol-based organic solvent to the first mixture and lowering the viscosity of the first mixture.

In a preferred aspect of the present invention, the back reinforcing material is formed from a second mixture of an epoxy compound, a curing agent, and an inorganic filler. When inexpensive concrete is used as a back reinforcing material for supporting and reinforcing the surface resin layer of the case, the case becomes considerably heavy in weight, and the case is gently cured, so that the case is warped or deformed. An epoxy compound is preferable in consideration of the adhesiveness to the surface resin layer. Mixing an inorganic filler with the epoxy compound is effective in reducing costs and improving strength.

In a preferred embodiment of the present invention, the second mixture is a mixture of an epoxy compound and a curing agent 3 to 20.
The mixing ratio of the inorganic filler is 80 to 97% by weight with respect to the weight%. When the amount of the inorganic filler is 97% by weight or more, the strength of the back reinforcing material is significantly reduced. When the content is less than 80% by weight, shrinkage, deformation,
Warpage increases. By setting the blending ratio of the inorganic filler in the back reinforcing material to 80 to 97, it is possible to reduce the material cost of the back reinforcing material, improve the strength, and suppress the shrinkage and deformation.

In a preferred aspect of the present invention, glass fibers and / or carbon fibers are provided as a reinforcing material at a boundary between the back reinforcing material and the surface resin layer. By interposing glass fiber and / or carbon fiber as a reinforcing material at a boundary surface between the back reinforcing material and the surface resin layer, the surface strength of the case is increased,
Repeated durability of casting and demolding of the slurry for forming a porous body is improved.

In a preferred aspect of the present invention, an elastic resin material is provided on a part of the surface of the working case for producing the slip casting mold. By partially using an elastic resin material such as a urethane resin or a synthetic rubber, it is possible to easily remove a complicated-shaped portion that is difficult to remove.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, bisphenol A type, bisphenol AD type and bisphenol F are used as main constituent materials for forming a surface resin layer of a case.
An epoxy compound containing a compound having an epoxy group such as allyl glycidyl ether, phenyl glycidyl ether, epichlorohydrin, styrene oxide, butyl glycidyl ether as a reactive diluent for diglycidyl ether represented by a type, and a filler for the epoxy compound As calcium carbonate, silicon oxide, kaolin clay,
A mixture (main component constituting material) obtained by adding and mixing 20 to 60% by weight of an inorganic filler typified by talc, mica, or the like, whose viscosity is adjusted to 30,000 to 300,000 mPa · s is suitably used.

[0023] The curing agent constituent raw material is selected from polyamidoamine, polyamine, polysulfide, acid anhydride, imidazole derivative, and polythiol compound. A mixture (hardening agent constituent material) of 30-60% by weight of an inorganic filler typified by calcium carbonate, silicon oxide, kaolin clay, talc, mica, etc.
Those prepared to have a viscosity of 00 to 200,000 mPa · s are preferably used.

The raw material constituting the main agent is weighed at a ratio of 1% by weight to the raw material constituting the curing agent with respect to 0.5 to 2% by weight, and mixed and stirred. At this time, the viscosity of the mixture is 40,000 to 3,000.
It is preferable to be within the range of 00 mPa · s.

As the back reinforcing material, bisphenol A
Type, bisphenol AD type, diglycidyl ether represented by bisphenol F type as reactive diluents allyl glycidyl ether, phenyl glycidyl ether,
An epoxy compound containing a compound having an epoxy group such as epichlorohydrin, styrene oxide, butyl glycidyl ether, and a polyamideamine, a polyamine, a polysulfide, an acid anhydride, an imidazole derivative, and a polythiol-based curing agent with respect to the epoxy compound. % By weight, and a mixture obtained by adding 80 to 95% by weight of silica powder, glass powder, calcium carbonate, etc. of about 1 to 4 mm as an inorganic filler to the mixture is preferably used.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, as one embodiment of the preparation of raw materials for forming a working case for a slurry casting mold according to the present invention, FIG. 3 shows the preparation of a main component constituting raw material for forming a surface resin layer, and FIG. FIG. 5 shows the contents of the raw material for forming the surface resin layer, and FIG. 5 shows the contents of the raw material for forming the back reinforcing material.

Next, an embodiment of a method of manufacturing a working case for a slurry casting mold using the raw materials shown in FIGS. FIG. 1 is a sectional view of a working case for producing a slip casting mold. A is a case made of a slurry casting mold, 1 is a surface resin layer, 2 is a back reinforcing material, and 3 is a metal reinforcing frame. A metal reinforcing frame represented by iron or aluminum is set on a matrix for forming a working case for a slip casting mold. The raw materials constituting the main ingredient shown in FIG. 3 are weighed and mixed in advance, and stored in a highly airtight closed container. Similarly, the curing agent constituent materials shown in FIG. 4 are weighed and mixed, and stored in a highly airtight closed container. Store each container in a cool, dark place. When storing for a long time, the air in the closed container should be N ₂
Replace with an inert gas such as At the time of molding the working case of the slurry casting mold, 1 part by weight of the hardener constituting material and 1 part by weight of the hardening agent constituting material in the closed container are weighed, and after mixing and stirring, the slurry is mixed. It is applied to the inner surface of a matrix and a reinforcing frame for molding a casting mold working case by about 2 to 5 mm. After curing, the same surface is applied again, and the back reinforcing material 2 shown in Table 5 is prepared in a semi-cured state. . After the back reinforcing material is hardened, the casting mold and the working case for the slip casting mold are turned over, and the casting mold is removed from the casting mold to obtain the working case for the casting mold.

Next, a description will be given of a state in which a slurry for forming a porous body is cast using the slurry casting mold manufacturing case A of FIG. 1 to form a continuous porous body constituting the slurry casting mold. First, as shown in FIG. 2, the lid case 4 is set in the working case A for producing a slip casting mold. Next, the slurry 6 for forming a porous body is poured into the space 7 formed by the lid case 4 and the surface resin layer 1. Slurry for forming porous body 6
After the hardening, the lid case 4 is removed, and the hardened porous body is removed from the working case A of the slurry casting mold.

On a portion of the cured porous body having a complicated shape portion where removal from the mold is difficult, urethane resin previously molded is adhered to the surface resin layer 1 of the working case A of the slurry casting mold forming mold. This is because the porous body that expands and contracts during the curing process of the slurry for forming a porous body may stick to the case when the mold is released, making it difficult to remove the porous body. By using such an elastic material, the cured porous body can be easily released from the mold. Further, the casting of the slurry 6 for forming a porous body and the demolding of the cured porous body are repeated so that the surface resin layer 1 of the working case A of the working case A is particularly required in a place where strength is required.
When forming the surface resin layer 1 at the boundary with the back reinforcing layer 2 or in the process of laminating and forming the surface resin layer 1
By interposing the glass fiber therein, the strength of the surface resin layer 1 can be improved.

Next, by applying the above-described manufacturing method, the deformation amount of the working case made of the slip casting mold manufactured using various surface resin layers and back reinforcing materials was measured. The measurement of the deformation amount was performed in the following manner. 1) Dimensions of rod-shaped test piece for measuring deformation amount Thickness of case surface resin layer = 5 mm, thickness of back reinforcing material = 95 mm External dimensions: 100 mm long × 100 mm wide × 900 m long
m 2) Method of measuring deformation amount FIG. 7 is an explanatory diagram of a method of measuring the deformation amount. The rod-shaped specimen is placed on two fulcrums with the case surface resin layer facing upward, and the amount of deformation of the rod-shaped specimen is measured over time. The distance between the two fulcrums is 840 mm, and the amount of deformation is measured at three points: the center of the top surface of the rod-shaped specimen and 225 mm from the center. Was measured.

FIG. 6 shows the results of measuring the amount of deformation of the working cases of the various types of slip casting molds measured in the manner described above. From FIG. 6, the deformation of the working case of the slip casting mold is based on whether or not there is an inorganic filler in the surface resin layer, the ratio of the resin component and the inorganic filler in the back reinforcing material, the particle size of the inorganic filler, and the curing agent. It can be seen that the type is affected. The deformation amount of the slip casting mold production case made from the raw materials having the contents described in FIGS. 3, 4, and 5 was about 0.1 mm, which was very good.

[0032]

According to the present invention, the case surface layer is made of an epoxy resin in which a main component constituting material in which an inorganic filler is mixed with an epoxy compound and a curing agent constituting material in which a curing agent and an inorganic filler are mixed, and a back portion is formed. Lays a mixture of an epoxy compound and a curing agent mixed with an inorganic filler on top of the case surface layer, and sets a metal reinforcing frame to improve the durability and shrinkage of the sludge casting mold production case. It is possible to provide an operation case for producing a slip casting mold at low cost while suppressing deformation and warpage.

[Brief description of the drawings]

FIG. 1 is a sectional view of a working case for producing a slurry casting mold according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing a state in which a slurry for forming a porous body is cast using the operation case for producing a slurry casting mold of FIG. 1;

FIG. 3 is a diagram showing the contents of a raw material constituting a surface resin layer.

FIG. 4 is a diagram showing the contents of a raw material constituting a hardening agent for forming a surface resin layer.

FIG. 5 is a table showing the preparation contents of the raw material constituting the back reinforcing material.

FIG. 6 shows the results of measuring the amount of deformation of working cases made of various types of slip casting molds.

FIG. 7 is an explanatory diagram of a method for measuring the amount of deformation.

[Explanation of symbols]

 A: Slurry cast mold working case 1 ... Surface resin layer 2 ... Back reinforcement 3 ... Metal reinforcement frame 4 ... Lid case 5 ... Porous material forming slurry injection port 6 ... Porous material forming slurry 7 … Casting space

Claims (11)

[Claims] 1. A working case for a slip casting mold, comprising: a surface resin layer; and a back reinforcing material for supporting and reinforcing the surface resin layer. 2. A method for producing a slip casting mold, comprising: a surface resin layer; a back reinforcing material for supporting and reinforcing the surface resin layer; and a reinforcing frame body for supporting and reinforcing the back reinforcing material. Case. 3. The surface resin layer comprises a main component constituting material comprising at least an epoxy compound and an inorganic filler, and at least one selected from polyamidoamine or polyamine, acid anhydride, imidazole derivative and polythiol compound. The main mixture is formed from a first mixture of a curing agent constituent material comprising two curing agents and an inorganic filler, and at least one kind of inorganic filler in the main constituent material is 20 to 60 in weight ratio to the total amount of the main constituent material. 3. The composition according to claim 1, wherein at least one kind of inorganic filler is contained in the hardener constituent material, and a weight ratio to the total amount of the hardener constituent material is 30 to 60% by weight. The operation case for producing a slip casting mold according to 1. 4. A method according to claim 1, wherein the first mixture comprises 0.5 to 0.5
4. The working case for a slip casting mold according to claim 3, wherein a mixing ratio of 1% by weight of the raw material constituting the curing agent is 2% by weight. 5. The surface resin layer has a thickness of 0.1 to 30.
5. The working case for producing a slip casting mold according to claim 1, wherein the diameter is mm. 6. The viscosity of the first mixture is 4 at room temperature.
The case for producing a slip casting mold according to claim 3 or 4, wherein the working case is 3,000 to 300,000 mPa · s. 7. The operation case for producing a slip casting mold according to claim 3, wherein the first mixture contains an alcohol-based organic solvent. 8. The back reinforcing material is an epoxy compound,
The working case for producing a slip casting mold according to any one of claims 1 to 7, wherein the case is formed from a second mixture of a curing agent and an inorganic filler. 9. The second mixture comprises 3-20% by weight of a mixture of an epoxy compound and a curing agent, and 80-80% of an inorganic filler.
9. The composition according to claim 8, wherein the mixing ratio is 97% by weight.
The operation case for producing a slip casting mold according to 1. 10. A glass fiber and / or carbon fiber as a reinforcing material at a boundary between the back reinforcing material and the surface resin layer.
0. A case for producing a slip casting mold according to any one of the above items 0. 11. The working case for producing a slip casting mold according to claim 1, wherein an elastic resin material is disposed on a part of the surface of the working case for producing the casting mold for slurry.