KR20170089840A - Coating agent composition for evaporative pattern - Google Patents

Abstract

The present invention relates to a mold composition for a mold disappearance model containing refractory aggregates and uncured celluloses and a mold for casting molds having a mold film around the mold, And a step of forming a patterned film by attaching the mold to the casting mold. According to the present invention, it is possible to provide a mold-stopping composition for a disappearance model and a method for producing a mold that are highly safe and can further suppress residual defects.

Description

TECHNICAL FIELD The present invention relates to a COATING AGENT COMPOSITION FOR EVAPORATIVE PATTERN,

The present invention relates to a mold release composition for a fume model attached to the periphery of a fume model.

The disappearance model casting method is a casting method in which a synthetic resin foam model having the same shape as a product is replaced with a molten metal (hereinafter also referred to as " molten metal "), Delivery time, and so on. Therefore, it is a casting method which has been attracting attention recently. In this casting method, since the synthetic resin foam is pyrolyzed by the molten metal injected, a large amount of pyrolysis gas and residues are disadvantageous in that residual defects are generated in the casting. Particularly, when polystyrene is used as a synthetic resin foam, the casting surface is deteriorated by the carbonized component.

In the disappearing model casting method, the mold release agent for the disappearance model is a "residue defect" caused by pyrolysis of a synthetic resin foam model, and a "defective defect" in which the molten metal leaks into the mold (sand mold) .

A residue defect is a phenomenon in which, when the synthetic resin foam model is replaced with a molten metal, the pyrolysis gas is insufficiently discharged, the pyrolysis residue is caught in the upper part of the product. In order to prevent such " residue defects ", it is required that the pyrolysis gas of the synthetic resin foam model be efficiently discharged to the mold side. As for the " adhesion defect ", it is required to continue to be maintained as a strong film until solidification of the molten metal is completed.

Japanese Patent Laid-Open Publication No. 3-180244 discloses a nitrocellulose composition which is insoluble in water and soluble in a hydrophilic organic solvent. The composition of the present invention for the dissolution model is selected from a material which is white-precipitated and micro-dispersed in a water-hydrophilic organic solvent system, and nitrocellulose is micro-dispersed and micro-dispersed in a liquid to reduce residue defects. Japanese Patent Application Laid-Open No. 2001-1104 discloses a mold-forming composition containing an organic solid to reduce residual defects.

The mold-making composition for the dissolution model of the present invention contains refractory aggregate and uncured cellulosic.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view of a disappearance model used in the evaluation of the embodiment. Fig.

In the conventional composition for forming a mold for a disappearance model, prevention of residual defects is not sufficient and further improvement is required. In addition, nitrocellulose is used in the composition of a mold for a disappearance model related to Japanese Unexamined Patent Application Publication No. 3-180244, which poses a problem in safety.

The present invention provides a mold release composition for a destruction mold which has high safety and can further suppress residual defects.

The mold-making composition for the dissolution model of the present invention contains refractory aggregate and uncured cellulosic.

According to the present invention, it is possible to provide a mold-stopping composition for a disappearance model that is highly safe and can further suppress residual defects.

Hereinafter, an embodiment of the present invention will be described.

≪ Composition for mold for dissolving mold >

The mold release composition for a disappearance model (hereinafter simply referred to as "mold release composition") of the present embodiment contains refractory aggregate and uncured cellulosic. According to the composition of the present invention, the composition for a mold disappearance model has high safety and exhibits an effect of further suppressing residual defects. The reason for achieving such an effect is not clear, but is considered as follows.

In order to prevent residue defects, it is important that the pyrolysis gas of the synthetic resin foam model is efficiently discharged from the mold film until the casting is completed. In the mold release composition according to the present embodiment, since the refractory aggregate of the mold release composition contains unconditioned cellulose, the non-purified cellulose is present dispersed in the mold film. Since the unmodified cellulose is burned by the heat at the time of casting, the portion where the untreated cellulose is present becomes void. It is considered that this gap becomes a gas hole, and the pyrolysis gas of the synthetic resin foam can be efficiently discharged, so that the residue defects can be reduced.

Hereinafter, the components contained in the mold-stopping composition for a disappearance model of the present embodiment will be described.

[Fireproof aggregate]

The mold stopper composition according to the present embodiment contains refractory aggregate. As the refractory aggregate, refractory aggregates conventionally used for the purpose of casting can be used. Examples of the refractory aggregate include mica, obsidian, perlite, sandstone, quartzite, zircon, calcite, silica, alumina, mullite, shaft bauxite, diaspore, spinel, magnesia, olivine, talc, zircon , Kaolin, silymarinite, anthracite, kyanite, gibbsite, black stone, dickite, plaster stone, graphite and bauxite. The refractory aggregate may be used as one or more of the above-mentioned refractory aggregates.

The average particle size of the refractory aggregate is preferably 20 占 퐉 or more, more preferably 40 占 퐉 or more, and most preferably 50 占 퐉 or more, from the viewpoint of preventing residue defects. The average particle diameter of the refractory aggregate is preferably 400 占 퐉 or less, more preferably 200 占 퐉 or less, and even more preferably 150 占 퐉 or less, from the viewpoint of preventing the occurrence of an occurrence of an adhesion defect. The average particle size of the refractory aggregate is preferably 20 to 400 占 퐉, more preferably 40 to 200 占 퐉, and still more preferably 50 to 150 占 퐉. The average particle size of the refractory aggregate is measured by the method described in the embodiment.

The content of the refractory aggregate of the mold-forming composition of the present embodiment is preferably not less than 30% by mass, more preferably not less than 40% by mass from the viewpoint of prevention of coating film defects such as drying and cracking. The content of the refractory aggregate of the mold release composition of the present embodiment is preferably 80% by mass or less, and more preferably 70% by mass or less, from the viewpoint of coating workability. The content of the refractory aggregate in the mold-stopping composition of the present embodiment is preferably 30 to 80 mass%, more preferably 40 to 70 mass%.

[Unmodified Cellulose]

The non-purified cellulose is a cellulose in which the crystal structure of cellulose, which is a carbohydrate (polysaccharide) represented by the molecular formula (C ₆ H ₁₀ O ₅ ) n, is uncured.

In the present specification, the term "uncured cellulose" means cellulose having a crystallinity of 33% or less.

In the present specification, the crystallinity of cellulose is a cellulose I-form crystallinity calculated from the diffraction intensity value by the X-ray diffraction method by the Segal method and is defined by the following calculation formula (A).

Cellulose I-form crystallinity (%) = [(I _22.6 - I _18.5 ) / I _22.6 ] x 100 (A)

_Wherein I _22.6 represents the diffraction intensity of the lattice plane (002 plane) (diffraction angle 2? = 22.6 °) in the X-ray diffraction and I _18.5 represents the diffraction intensity of the amorphous portion (diffraction angle 2θ = 18.5 °) ]

As shown in the above formula (A), the cellulose I-form crystallinity has a diffraction angle of 22.6 deg. (Peak corresponding to the crystallinity 002 plane) and 18.5 deg. (Peak corresponding to the amorphous portion) of the X- ) ≪ / RTI > I _22.6 < I _18.5 (in short, calculated according to this definition becomes a negative value). On the other hand, the upper limit of the degree of crystallinity of the cellulose I type is 100%. The cellulose I type refers to a crystalline form of natural cellulose.

The degree of crystallinity is preferably 30% or less, more preferably 25% or less, and even more preferably 20% or less from the viewpoint of suppressing residual defects. The degree of crystallinity is preferably -30% or more, more preferably -20% or more, and even more preferably -10% or more from the viewpoint of the cost of the purification treatment. The crystallinity is preferably -30% to 30%, more preferably -20% to 25%, and even more preferably -10% to 20%.

The degree of crystallization of the cellulose in this case means the degree of crystallinity determined by the weighted average of the cellulose to be used, and the value is preferably within the above range.

In order for the gas to be generated after the cellulose dispersed in the graphite film disappears after combustion, it is necessary that the gas ball is present until the combustion is completed at the temperature of 250 to 400 캜, which is the temperature of the gas layer at the casting, until the casting is completed. Therefore, uncured cellulose which is decomposed at 250 to 400 DEG C and has a reduced residual rate and ashes after decomposition is preferable.

The shape of the uncured cellulosic is not particularly limited, and a fibrous or particulate form can be used, but a particulate form is preferable from the viewpoint of coating workability.

When the shape of the non-purified cellulose is particulate, the average particle diameter of the uncured cellulose is preferably 50 占 퐉 or more, more preferably 80 占 퐉 or more from the viewpoint of reduction of residue defects. The average particle diameter of the uncured cellulose is preferably 500 탆 or less, more preferably 200 탆 or less from the viewpoint of reducing the occurrence of the defect. The average particle diameter of the non-purified cellulose is preferably 50 to 500 占 퐉, more preferably 80 to 200 占 퐉. Further, in the present specification, the average particle diameter is measured by the method described in Examples.

When the shape of the uncured cellulose is fibrous, the fiber length of the uncured cellulose is preferably 50 占 퐉 or more, more preferably 80 占 퐉 or more, and even more preferably 120 占 퐉 or more from the viewpoint of reduction of residue defects. The fiber length of the uncured cellulose is preferably 600 탆 or less, more preferably 300 탆 or less, from the viewpoint of reducing the occurrence of the defect. The fiber length of the uncured cellulose is preferably 50 to 600 占 퐉, more preferably 80 to 300 占 퐉, and even more preferably 120 to 300 占 퐉.

When the shape of the non-purified cellulose is fibrous, the fiber diameter of the non-purified cellulose is preferably 10 占 퐉 or more, more preferably 20 占 퐉 or more from the viewpoint of reduction of residue defects. The fiber diameter of the non-purified cellulose is preferably 80 占 퐉 or less from the viewpoint of coating property into a synthetic resin foam model. The fiber diameter of the non-purified cellulose is preferably 10 to 80 mu m, more preferably 20 to 80 mu m.

The content of the untreated cellulose in the composition for forming a pattern according to the present embodiment is preferably not less than 1 part by mass from the viewpoint of reduction of residue defects, that is, from the viewpoint of ensuring a void to be a gas hole, More preferably at least 4 parts by mass, and still more preferably at least 4 parts by mass. The content of the untreated cellulose in the composition for forming a pattern according to the present embodiment is preferably 12 parts by mass or less, more preferably 10 parts by mass or less from the viewpoint of the removal defect (coating film strength at the time of heating) with respect to 100 parts by mass of the refractory aggregate More preferably 7 parts by mass or less. The content of the untreated cellulose in the composition for forming a pattern according to the present embodiment is preferably 1 to 12 parts by mass, more preferably 3 to 10 parts by mass, and even more preferably 4 to 7 parts by mass, per 100 parts by mass of the refractory aggregate .

The method for producing the uncured cellulose is not particularly limited and, for example, Japanese Unexamined Patent Application Publication Nos. 62-126999, 62-127000, 62-236801, 62-236801, Can be obtained by the methods described in publications such as JP-A 2003-64184, JP-A 2004-331918, JP 4160108, JP 4160109, and JP-A No. 2011-1547.

[Dispersing agent]

In the disappearing model casting method of the present embodiment, since the air gap after burning and disappearance of the uncured cellulose by the heat at the time of casting is used as a gas hole, voids serving as gas holes are hardly formed by using a dispersion medium for dissolving the uncured cellulose . Therefore, it is preferable that the dispersion medium does not dissolve the uncured cellulose.

As the dispersion medium, for example, alcohol or water can be used.

In the case of an alcohol type composition, from the viewpoint of drying property, lower alcohols such as methanol, ethanol and isopropyl alcohol are preferable, and ethanol is more preferable. In the case of an alcohol type composition, an aromatic solvent or a hydrocarbon solvent may be used as an auxiliary dispersion medium.

The amount of the dispersion medium in the alcohol type mold release agent composition can be appropriately changed depending on the kind of the dispersion medium to be used. For example, when the dispersion medium is a lower alcohol, the amount is preferably 20 parts by mass or more, and more preferably 70 parts by mass or more, based on 100 parts by mass of the refractory aggregate from the viewpoint of coating workability. The amount of the dispersion medium in the alcoholic graphitizing composition is preferably 120 parts by mass or less, more preferably 110 parts by mass or less, based on 100 parts by mass of the refractory aggregate, from the viewpoint of prevention of coating film defects such as drying and cracking, Do. The amount of the dispersion medium in the alcoholic graphitizing composition is preferably from 20 to 120 parts by mass, more preferably from 70 to 110 parts by mass, per 100 parts by mass of the refractory aggregate, from the viewpoint of forming a good coating film, .

In the case of the water-based composition, the amount of water in the water-based mold-making composition is preferably 20 parts by mass or more, more preferably 70 parts by mass or more based on 100 parts by mass of the refractory aggregate from the viewpoint of coating workability. In the case of a water based composition, the amount of water in the water based mold composition is preferably 150 parts by mass or less, more preferably 130 parts by mass or less, based on 100 parts by mass of the refractory aggregate from the viewpoint of drying property. In the case of a water-based composition, the amount of water in the water-based composition is preferably 20 to 150 parts by mass, more preferably 70 to 130 parts by mass, per 100 parts by mass of the refractory aggregate, from the viewpoint of coating workability and drying property.

[Point payment]

The composition for forming a pattern of the present embodiment may contain a commonly used binder. For example, water-soluble polymers such as sodium polyacrylate, starch, methyl cellulose, polyvinyl alcohol, sodium alginate, and gum arabic and various resin emulsions can be used as the binder. In addition, in the alcohol system, it is preferable to add various resins soluble or dispersible in alcohol in view of the strength of the coating film. The content of the binder is preferably 0.5 parts by mass or more, more preferably 30 parts by mass or less, based on 100 parts by mass of the refractory aggregate, from the viewpoints of film strength and economical efficiency. The content of the binder is preferably 0.5 to 30 parts by mass with respect to 100 parts by mass of the refractory aggregate from the viewpoints of film strength and economical efficiency.

[Small payment]

The mold-stopping composition of the present embodiment may contain a commonly used sintering agent. Examples of the sintering agent include bentonite such as sodium bentonite and calcium bentonite; clay such as clay clay; and ethyl silicate. Among them, bentonite is preferable in addition to its role as a binder, since it also fulfills its role as a sintering agent in a high temperature range. The addition amount of the sintering agent is preferably at least 0.5 part by mass, more preferably at least 1.0 part by mass, based on 100 parts by mass of the refractory aggregate, from the viewpoint of the coating film strength at high temperature. The addition amount of the sintering agent is preferably 30 parts by mass or less, more preferably 15 parts by mass or less, based on 100 parts by mass of the refractory aggregate, from the viewpoint of the film strength at high temperature. The addition amount of the sintering agent is preferably from 0.5 to 30 parts by mass, more preferably from 1.0 to 15 parts by mass, per 100 parts by mass of the refractory aggregate, from the viewpoint of the coating film strength at high temperature.

[Other components]

Examples of other components that can be blended in the composition of the present invention include a surfactant, a dispersant, and a thixotropic property-imparting agent.

The mold-forming composition of the present embodiment can be preferably used as a mold-stopping composition adhered to the periphery of a disappearing mold.

<Manufacturing Method of Casting Loss Model for Casting>

In the manufacturing method of the casting chamber for casting according to the present embodiment, a conventional manufacturing method for casting chamber for casting can be applied. A manufacturing method of a casting chamber mold for casting according to the present embodiment is a manufacturing method of a casting chamber mold for casting having a casting film around a casting mold, wherein the casting mold composition for a casting mold is attached to the periphery of the casting mold to form a casting film Process.

As the disappearance model to which the mold-stopping composition of the present embodiment is adhered, a model of a synthetic resin foam the same as usual can be used. As the synthetic resin foam, a foam such as polystyrene, methyl polymethacrylate, or a copolymer thereof is used. When the disintegration model to which the mold-stopping composition of the present embodiment is applied is foamed polystyrene, the effect of the mold-stopping composition of the present embodiment is further obtained. The method of forming the graphic film by adhering the composition of the present invention to the disappearance model may be any of conventionally known methods such as flow coating (dipping method), dipping (dipping method), brush application, spray coating and the like.

The casting chamber disappearance chamber model obtained by the manufacturing method of the casting chamber model of the present embodiment can be suitably used in the method of manufacturing the casting chamber by the dissolution chamber casting method.

<Manufacturing Method of Casting>

In the method of manufacturing a mold according to the dissolution chamber casting method of the present embodiment, a method of manufacturing a mold by a conventional dissolution chamber casting method can be applied. The method for producing a casting mold of the present embodiment is a method for producing a casting using a casting chamber for casting obtained by the manufacturing method of casting chamber for casting, And injecting the molten metal into the casting mold for casting embedded.

As the foundry sand used in the step of casting the casting mold for casting into the foundry sand, a shrine or regenerated yarn such as zircon yarn, chromite yarn, synthetic ceramics yarn or the like is used in addition to the silica yarn mainly composed of quartz. The molding sand can be used without adding a binder. In this case, the filling property is good. However, when a high-strength mold is required, it is preferable to add a conventionally known binder and harden it with a curing agent.

The method for producing a casting mold according to the present embodiment relating to the case where the binder is added is a method for producing a casting mold using a casting chamber for casting obtained by the manufacturing method of the casting chamber for casting, Adding a hardening agent for hardening to prepare a mixture; kneading the casting mold for the casting into the mixture; and injecting molten metal into the casting mold for casting embedded in the mixture.

As the binder, a commonly used binder may be used. As the binder, water-soluble polymers such as sodium polyacrylate, starch, methyl cellulose, polyvinyl alcohol, sodium alginate, and gum arabic, and various resin emulsions can be used in the aqueous system. In the alcohol system, it is preferable to add various resins soluble or dispersible in alcohol from the viewpoint of mold strength. The content of the binder is preferably at least 0.4 part by mass, more preferably at least 0.5 part by mass based on 100 parts by mass of the molding sand from the viewpoints of mold strength and economic efficiency. The content of the binder is preferably 1.2 parts by mass or less, more preferably 0.8 parts by mass or less, based on 100 parts by mass of the molding sand, from the viewpoints of mold strength and economical efficiency. The content of the binder is preferably from 0.4 to 1.2 parts by mass, more preferably from 0.5 to 0.8 parts by mass, per 100 parts by mass of the molding sand, from the viewpoints of mold strength and economical efficiency.

In the casting method of the present embodiment, the injection temperature differs depending on the metal used. In the cast iron system, the casting temperature is generally 1330 to 1410 deg. C, and in the case of aluminum system, the casting temperature is generally 700 to 750 deg. In the case of a steel system, it is generally 1450 to 1500 ° C. The defect model casting method of the present embodiment can reduce residual defects occurring in the cast iron system more particularly.

When a casting is produced by using the casting mold composition for a disappearance model, a casting having a small amount of residual defects and fewer defects is obtained and an excellent casting surface is obtained, so that a complicated structure and a beauty of the surface of the casting surface are required . Examples of concrete castings include automobile molds, machine tools, members used for hydraulic valves of construction machines, motors, engine frames, building members, and parts.

With regard to the above-described embodiments, the present invention further discloses the following composition, manufacturing method, or use.

&Lt; 1 &gt; A mold-making composition for a disappearance model containing refractory aggregate and uncured cellulosic.

<2> The average particle size of the refractory aggregate is preferably 20 μm or more, more preferably 40 μm or more, more preferably 50 μm or more, more preferably 400 μm or less, more preferably 200 μm or less, More preferably 20 to 400 占 퐉, more preferably 40 to 200 占 퐉, and still more preferably 50 to 150 占 퐉.

<3> The content of the refractory aggregate is preferably at least 30 mass%, more preferably at least 40 mass%, even more preferably at least 80 mass%, more preferably at most 70 mass%, even more preferably from 30 to 80 mass% , And more preferably from 40 to 70 mass%, based on the total amount of the composition.

The crystallinity of the uncapped cellulose is preferably 30% or less, more preferably 25% or less, still more preferably 20% or less, still more preferably -30% or more, still more preferably -20% , More preferably -10% or more, more preferably -30% to 30%, more preferably -20% to 25%, and even more preferably -10% to 20% &Lt; / RTI &gt;

<5> The mold composition for a destructible model according to any one of <1> to <4>, wherein the uncured celluloses are preferably fibrous and / or particulate in shape, and more preferably in granular form.

<6> The average particle diameter of the uncapped celluloses is preferably 50 μm or more, more preferably 80 μm or more, more preferably 500 μm or less, more preferably 200 μm or less, most preferably 50 to 500 μm, To 200 [mu] m is more preferable.

The fiber length of the uncapped cellulose is preferably 50 μm or more, more preferably 80 μm or more, more preferably 120 μm or more, more preferably 600 μm or less, still more preferably 300 μm or less, and most preferably 50 To 600 탆, more preferably 80 to 300 탆, and further preferably 120 to 300 탆.

<8> The fiber diameter of the uncapped cellulose is preferably 10 μm or more, more preferably 20 μm or more, more preferably 80 μm or less, more preferably 10 to 80 μm or more preferably 20 to 80 μm, 5 &gt; or &lt; 7 &gt;.

<9> The content of the uncured cellulose is preferably 1 part by mass or more, more preferably 3 parts by mass or more, further preferably 4 parts by mass or more, and most preferably 12 parts by mass or less based on 100 parts by mass of the refractory aggregate More preferably 1 to 12 parts by mass, still more preferably 3 to 10 parts by mass, still more preferably 4 to 7 parts by mass, still more preferably 10 parts by mass or less, still more preferably 7 parts by mass or less, 8] The composition for a mold disappearance model according to any one of [1] to [8].

<10> The composition for a mold disappearance model according to any one of <1> to <9>, further comprising a dispersing agent, wherein the dispersing agent does not dissolve the uncured cellulose.

<11> The mold composition according to <10>, wherein the dispersion medium is a lower alcohol, and more preferably ethanol.

The content of the dispersion medium is preferably 20 parts by mass or more, more preferably 70 parts by mass or more, more preferably 120 parts by mass or less, and most preferably 110 parts by mass or less, based on 100 parts by mass of the refractory aggregate. To 120 parts by mass is preferable, and 70 parts by mass to 110 parts by mass is more preferable.

&Lt; 13 &gt; The mold-detergent composition according to the above-mentioned &lt; 10 &gt;, wherein the dispersion medium is water.

The amount of the dispersion medium is preferably 20 parts by mass or more, more preferably 70 parts by mass or more, and further preferably 150 parts by mass or less, more preferably 130 parts by mass or less, and most preferably 20 to 150 parts by mass with respect to 100 parts by mass of the refractory aggregate. , More preferably 70 to 130 parts by mass is more preferable.

The content of the binder is preferably 0.5 part by mass or more, more preferably 30 parts by mass or less, more preferably 0.5 to 30 parts by mass, based on 100 parts by mass of the refractory aggregate. To &lt; 14 &gt;.

The addition amount of the sintering agent is preferably 0.5 parts by mass or more, more preferably 1.0 parts by mass or more, and preferably 30 parts by mass or less, more preferably 15 parts by mass or less, based on 100 parts by mass of the refractory aggregate, Or less, more preferably 0.5 to 30 parts by mass, and still more preferably 1.0 to 15 parts by mass, relative to 100 parts by mass of the resin composition.

&Lt; 17 &gt; The mold composition according to the above 16, wherein the sintering agent is calcium bentonite.

<18> A method for manufacturing a mold for casting having a mold film around a mold for destruction, comprising the step of attaching a mold composition for a mold disappearance model according to any one of <1> to <17> Wherein the method comprises the steps of:

<19> The method of manufacturing a disappearance chamber for casting according to <18>, wherein the disappearance model is foamed polystyrene.

<20> A method of manufacturing a casting using a casting chamber for casting obtained by the manufacturing method of casting chamber for casting according to <18> or <19>, the casting chamber comprising: A method for manufacturing a casting having a process of injecting molten metal into a casting mold for casting embedded in a molding sand.

<21> A method of producing a casting using a firing chamber for casting obtained by the manufacturing method of a casting chamber for casting according to any one of the above <18> or <19>, wherein a binder and a curing agent for curing the binder And a step of injecting molten metal into the casting chamber for casting embedded in the mixture. The method for casting a casting according to claim 1,

&Lt; 22 &gt; The use of a graphitizing composition for a disappearance model according to any one of &lt; 1 &gt; to &lt; 17 &gt;

Example

Best Mode for Carrying Out the Invention Hereinafter, embodiments and the like that specifically describe the present invention will be described.

<Evaluation method>

[Cellulose I-type crystallinity]

The cellulose I-form crystallinity was calculated on the basis of the above-mentioned calculation formula using the X-ray diffraction intensity of the sample measured under the following conditions using the trade name "Rigaku RINT 2500 VC X-RAY diffractometer", manufactured by Rigaku Corporation. The measurement sample was prepared by compressing pellets having an area of 320 mm 2 and a thickness of 1 mm.

· X-ray source: Cu / Kα-radiation

· Tube voltage: 40 ㎸ Tube current: 120 ㎃

· Measuring range: diffraction angle 2θ = 5 ~ 45 ° Scan speed: 10 ° / min

[TG decomposition starting temperature]

TG-8110 &quot; manufactured by Rigaku Corporation under the conditions of an alumina fan? 5 mm x 2.5 H, an air flow of 500 ml / min, and a heating rate of 5 占 폚 / min. The temperature at the time when the decrease of TG was started was set as the decomposition starting temperature.

[Average particle size]

The average particle size is an average particle size of 50% of volume cumulative as measured using a laser diffraction particle size distribution analyzer (LA-920 manufactured by Horiba Ltd.). The analysis conditions are as follows.

· Measurement method: Flow method

· Dispersion medium: ion-exchange water

· Dispersion method: stirring, internal ultrasonic 3 minutes

Sample concentration: 2 mg / 100 cc

[Evaluation method of residue defects]

Using the expanded polystyrene (expansion ratio of 50 times), the disappearance model 1 having the shape shown in Fig. 1 was produced. A casting mold for casting was made by attaching the moldable composition described below (dry film thickness: 1.4 mm) around the disappearance model. Then, 0.2 part by mass of an organic sulfonic acid curing agent (C-14, manufactured by Kao Quaker Co., Ltd.) was added to 100 parts by mass of Fremantle silica (No. 5) and kneaded. Thereafter, furan resin (EF- 0.5 parts by mass based on 100 parts by mass. The casting chamber for casting was embedded in the obtained kneading yarn, and the casting was carried out at a speed at which the molten metal did not overflow (cast iron: FC-250, injection temperature: 1400 ° C) And the castings were taken out. With respect to the obtained castings, the area (%) of residues generated on the two side surfaces of 400x100 on the side of the TP was measured by image analysis.

[Evaluation method of air permeability at 400 占 폚]

After completing the test piece, the moldings shown in the following Table 1 were heated in an oven capable of being maintained at 400 占 폚 占 10 占 폚 for 30 minutes and then cooled to room temperature to prepare a mold for casting a mold for disposing molds, (5) of the Test Method (March 1996). Air permeability test method &quot;. The air permeability after 6 minutes and after 60 minutes in the oven which can be maintained at 400 ° C ± 10 ° C was measured respectively, and after 6 minutes / 60 minutes, the air permeability was measured at 100 ° C Respectively. That is, it is an index showing the air permeability at the initial stage of heating, and the higher the value, the higher the air permeability at the initial stage of heating.

[Solid content 65% Viscosity]

To the graphant shown in Table 1, ion-exchanged water was added to adjust the solid content to 65%. Thereafter, the viscosity (mPa · s) after the 60-second hysteresis was measured under a condition of a shear rate of 10 s ^{-1 with} a rheometer (condition: parallel cone, 20 ° C., clearance 1 mm).

[1000 占 폚]

For the graphic form shown in Table 1, refer to "6. Test Method of Graphic Materials for Casting Loss Model Casting (March 1996)" issued by the Office of the Japanese Society of Foundry Engineering. Quot ;, and &quot; anti-perspiration measurement method &quot;. In addition, for the heat treatment at 1000 占 폚, scaled graphite having an average particle size of 60 占 퐉 was filled in a crucible of? 50 to make a non-oxidizing atmosphere, and a test piece was embedded therein. Thereafter, the sample was heated in a muffle furnace maintained at 1000 ° C ± 30 ° C for 1 hour, cooled to room temperature and measured. In addition to the heating process, &quot; 6. Quot; anti-perspiration measurement method &quot;.

&Lt; Preparation of uncured cellulose &gt;

("SG (E) -220" manufactured by Hoya Co., Ltd.) as a cellulose-containing raw material, sheet-form wood pulp ("HV-10" The obtained pulp was dried by a lathe dryer (manufactured by AdvanTech, vacuum calorimetric temperature dryer "DRV320DA") so that the dried pulp became 1.0% by mass. The pulp obtained in the drying treatment was placed in a batch-type vibrating mill ("MB-1" manufactured by Chuo Air Co., Ltd.) and the treatment time was adjusted to prepare a spherical sample having different degrees of crystallinity. The sample was sieved to obtain a non-purified cellulose having an average particle size shown in Table 1. In this connection, treatment was carried out for 10 minutes for 17% of crystallinity, 20 minutes for 4%, and 30 minutes for -15%. Regarding the particle size adjustment, sieving of 28 mesh (scale interval 589 mu m) was carried out to collect body part and minute particles. As for the granules, 300 .mu.m was sieved again with 100 mesh to collect the sieved fractions. 800 ㎛ collected 28 sieve body sieve.

&Lt; Preparation of composition for mold-

[Examples 1 to 9 and Comparative Examples 1 and 2]

100 parts by mass of the refractory aggregate (silica (60 mass%, average particle size 80 탆), obsidian (20 mass%, average particle size 93 탆), graphite (20 mass% , 3.0 parts by mass of a nonionic surfactant (Emergen 106 manufactured by Kao Corporation), 2.0 parts by mass of calcium bentonite, 2.0 parts by mass of polyvinyl alcohol, and 40 parts by mass of ion-exchanged water were mixed, A composition was prepared. The unit of the addition amount described in Table 1 is parts by mass. In addition, the concentration of the mold release agent was determined by the following operation.

[Determination method of concentration of graphite]

A foamed polystyrene model of 300 × 150 (mm) is set on the upper side of the elevation angle of 30 ° and 150 mm, and the flow coating is performed in one reciprocating motion. After drying at 50 DEG C for 1 hour, the coating is again carried out by the same operation and dried. The coatings were peeled off, four points were measured with a vernier caliper, and the amount was adjusted and the concentration was determined so that the average value thereof was in the range of 1.4 mm 0.1.

Claims (9)

A mold release composition for a waste disposal model containing refractory aggregate and uncured cellulosic. The method according to claim 1,
Wherein the crystallinity of the uncured cellulose is 30% or less. 3. The method according to claim 1 or 2,
Wherein the desiccated cellulose is in a particulate form. The method of claim 3,
Wherein the average particle size of the uncured cellulose is 50 to 500 占 퐉. 5. The method according to any one of claims 1 to 4,
Wherein the content of the uncured cellulose is 1 to 12 parts by mass with respect to 100 parts by mass of the refractory aggregate. 6. The method according to any one of claims 1 to 5,
Further comprising a dispersing agent, wherein the dispersing agent does not dissolve the uncured cellulose. A method for manufacturing a mold for casting having a mold film around a mold,
A method for manufacturing a disappearance mold for casting, comprising the step of forming a graphic film by adhering a graphite composition for a fade model according to any one of claims 1 to 6 to the periphery of the fade model. A method for producing a casting using the firing chamber for casting obtained by the manufacturing method of the casting chamber for casting according to claim 7,
A step of burying the casting mold for casting in a molding sand;
And injecting the molten metal into the casting mold for casting embedded in the casting mold. Use of the composition according to any one of claims 1 to 6 as a demolding agent for the disappearing model.

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