Binder composition for casting moldes

Abstract

The present invention is a binder composition for molding molds, which contains furfuryl alcohol, a furan resin, water and a phosphate salt, and satisfies the following conditions (1)-(4). Condition (1): the content of furfuryl alcohol in the binder composition for molding molds is more than 0% by mass and 30% by mass or less; condition (2): the content of the furan resin in the binder composition for molding molds is from 20% by mass to 60% by mass (inclusive); condition (3): the content of water in the binder composition for molding molds is from 5% by mass to 30% by mass (inclusive); condition (4): The phosphate salt contains an amine phosphate salt. According to the present invention, it is possible to provide a binder composition for molding, which contains a furan resin in which phosphoric acid is used as an acid catalyst during production, and which is capable of suppressing thickening during storage of the binder composition for molding having a low furfuryl alcohol content, and suppressing precipitation of an insoluble phosphate salt.

Description

Technical Field

[0001] The present invention relates to a binder composition for casting mold making. Background Art

[0002] Generally speaking, the acid curing casting mold is manufactured in the following manner, that is, the casting mold molding binder composition and the casting mold molding curing agent composition are supplied to the mixer by the supply device through the pipe, and after mixing with the refractory particles, the obtained mixed sand is filled into the original mold such as the wooden mold, and the acid curing resin is cured and manufactured. The acid curing resin uses furan resin or phenol resin, etc., and the furan resin uses furan methanol-urea-formaldehyde resin, furan methanol-formaldehyde resin, furan methanol-phenol-formaldehyde resin, other known modified furan resins, etc. This method for manufacturing a casting mold can realize a high degree of freedom molding operation, and in addition, the thermal properties of the casting mold are excellent, so high-quality castings can be manufactured, and therefore, it is widely used when casting castings such as casting machinery parts, construction machinery parts, or automotive parts.

[0003] One of the important conditions for mold manufacturing is to improve the working environment during mold manufacturing (during resin curing). In particular, it is desirable to reduce furanol and formaldehyde volatilized during mold manufacturing to reduce furanol in the binder composition for mold making.

[0004] For example, Japanese Patent Publication No. 2014-501175 discloses that the release of furanol and formaldehyde during kneading and molding can be reduced by using a binder composition containing a small amount of monomeric furanol.

[0005] On the other hand, the binder composition for mold making containing furan resin is used in a wide range of climates from cold regions to warm regions. However, under high temperature environments in summer in warm regions (e.g., above 35°C), there is a problem of storage stability, namely, viscosity increase. If viscosity increase occurs, the handling property during mold making will change. Therefore, from the perspective of quality management of the mold, it is sometimes necessary to change the settings of equipment such as infusion pumps, which is more complicated. In particular, the binder composition for mold making with reduced furan carbinol content, such as that disclosed in Japanese Patent Table No. 2014-501175, has a larger viscosity increase during storage than the binder composition for mold making containing a large amount of furan carbinol. It is believed that the reason is that the cost of reducing furan carbinol is that a large amount of oligomer components such as urea-modified furan resins are contained in the binder composition, and thus a condensation reaction is carried out during storage, and the molecular weight becomes larger, so a means of suppressing viscosity increase is required.

[0006] For example, Japanese Patent Application Laid-Open No. 2012-135778 discloses that by adding a metal hydroxide to a binder composition for mold making, the viscosity increase of the binder composition can be suppressed.

[0007] In addition, urea-modified furan resin, furan carbinol-formaldehyde condensate, and the like, which are the main components of the furan resin, are obtained by reacting furan carbinol with urea or formaldehyde in the presence of an acid catalyst.

[0008] For example, Japanese Patent Application Laid-Open No. 2011-147999 discloses that, in addition to sulfonic acids such as p-toluenesulfonic acid and xylenesulfonic acid, and organic carboxylic acids such as glutaric acid and succinic acid, inorganic acids such as hydrochloric acid and phosphoric acid may be used as the acid catalyst. Summary of the invention

[0009] The present invention is a binder composition for casting molds, which contains furan carbinol, furan resin, water and phosphate and satisfies the following conditions (1) to (4).

[0010] Condition (1): The content of furanol in the above-mentioned binder composition for casting mold making is more than 0 mass % and is 30 mass % or less;

[0011] Condition (2): The content of the furan resin in the binder composition for casting mold making is 20% by mass or more and 60% by mass or less;

[0012] Condition (3): The water content in the above-mentioned binder composition for casting mold making is 5 mass % or more and 30 mass % or less;

[0013] Condition (4): The phosphate salt comprises amine phosphate.

[0014] The present invention also provides a casting mold molding composition comprising the above-mentioned casting mold molding binder composition and a curing agent composition containing a curing agent for curing the casting mold molding binder composition.

[0015] The present invention also provides a composition for a foundry mold, comprising refractory particles, the above-mentioned binder composition for foundry mold making, and a curing agent composition containing a curing agent for curing the binder composition for foundry mold making.

[0016] In addition, the present invention is a method for manufacturing a casting mold, which includes: a mixing step, in which refractory particles, the above-mentioned casting mold molding binder composition, and a curing agent composition containing a curing agent that cures the casting mold molding binder composition are mixed to obtain a casting mold composition; and a curing step, in which the above-mentioned casting mold composition is filled into a mold frame and the casting mold composition is cured. DETAILED DESCRIPTION

[0017] It has been found that when a furan resin is contained and phosphoric acid is used as an acid catalyst during production, and a metal oxide is contained in the binder composition for mold making in order to suppress the viscosity increase of the binder composition for mold making having a low furan carbinol content, there is a concern that the metal oxide forms an insoluble salt with phosphoric acid and precipitates, causing failures in the supply device and piping during mold manufacturing.

[0018] The present invention provides a furan resin containing phosphoric acid as an acid catalyst during production, a binder composition for mold making which can suppress the viscosity increase of a binder composition for mold making having a low furan carbinol content during storage and suppress the precipitation of insoluble phosphate, a mold making composition, a mold composition and a method for producing a mold.

[0019] The present invention is a binder composition for casting molds, which contains furan carbinol, furan resin, water and phosphate and satisfies the following conditions (1) to (4).

[0020] Condition (1): The content of furanol in the above-mentioned binder composition for casting mold making is more than 0 mass % and is 30 mass % or less;

[0021] Condition (2): The content of the furan resin in the binder composition for casting mold making is 20% by mass or more and 60% by mass or less;

[0022] Condition (3): The water content in the above-mentioned binder composition for casting mold making is 5 mass % or more and 30 mass % or less;

[0023] Condition (4): The phosphate salt comprises amine phosphate.

[0024] The present invention also provides a casting mold molding composition comprising the above-mentioned casting mold molding binder composition and a curing agent composition containing a curing agent for curing the casting mold molding binder composition.

[0025] The present invention also provides a composition for a foundry mold, comprising refractory particles, the above-mentioned binder composition for foundry mold making, and a curing agent composition containing a curing agent for curing the binder composition for foundry mold making.

[0026] In addition, the present invention is a method for manufacturing a casting mold, which includes: a mixing step, in which refractory particles, the above-mentioned casting mold molding binder composition, and a curing agent composition containing a curing agent that cures the casting mold molding binder composition are mixed to obtain a casting mold composition; and a curing step, in which the above-mentioned casting mold composition is filled into a mold frame and the casting mold composition is cured.

[0027] According to the present invention, there can be provided a furan resin containing phosphoric acid as an acid catalyst during production, a binder composition for mold making that can suppress the viscosity increase during storage of a binder composition for mold making having a low content of furan carbinol and suppress the precipitation of insoluble phosphate, a composition for mold making, a composition for mold making, and a method for producing a mold.

[0028] Hereinafter, one embodiment of the present invention will be described.

[0029] <Binder composition for casting mold>

[0030] The binder composition for casting mold making of the present embodiment (hereinafter, also simply referred to as a binder composition) contains furanol, furan resin, water, and phosphate, and satisfies the following conditions (1) to (4).

[0031] Condition (1): The content of furanol in the above-mentioned binder composition for casting mold making is more than 0 mass % and is 30 mass % or less;

[0032] Condition (2): The content of the furan resin in the binder composition for casting mold making is 20% by mass or more and 60% by mass or less;

[0033] Condition (3): The water content in the above-mentioned binder composition for casting mold making is 5 mass % or more and 30 mass % or less;

[0034] Condition (4): The phosphate salt comprises amine phosphate.

[0035] According to the binder composition of this embodiment, the thickening can be suppressed and the precipitation of insoluble phosphate can be suppressed. The reason why the above-mentioned binder composition exerts such an effect is not yet clear, but it is considered as follows: by using an alkylamine as an alkali component when neutralizing phosphoric acid, the condensation of the furan resin is suppressed, and the generated phosphate increases the solubility in the furan resin through the alkyl chain of the alkylamine, thereby becoming soluble.

[0036] [Furanol]

[0037] Regarding the content of furan methanol in the above-mentioned binder composition, from the perspective of improving the working environment, it is 30% by mass or less, preferably 25% by mass or less, more preferably 20% by mass or less, and further preferably 15% by mass or less. Regarding the content of furan methanol in the above-mentioned binder composition, from the perspective of improving the strength of the mold, it is preferably more than 0% by mass, more preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 15% by mass or more. It should be noted that the content of furan methanol in the above-mentioned binder composition can be measured using the method described in the examples.

[0038] [Furan resin]

[0039] The furan resin is obtained by polymerizing a monomer composition containing furan carbinol using phosphoric acid as an acid catalyst, and can be used without particular limitation as long as it can be used as a binder for mold making. With regard to the furan resin, from the viewpoint of reducing the content of furan carbinol in the binder composition for mold making and improving the strength of the mold, it is preferred to contain one or more selected from the following substances: a condensate of furan carbinol and urea, a condensate of furan carbinol and melamine, a condensate of furan carbinol and ethylene urea, a condensate of furan carbinol and urea and aldehydes (urea-modified furan resin), a condensate of furan carbinol and melamine and aldehydes, a condensate of furan carbinol and ethylene urea and aldehydes, a condensate of furan carbinol, a condensate of furan carbinol and aldehydes, and a condensate of furan carbinol and phenols and aldehydes; and a co-condensate of two or more selected from them. More preferably, the polyol contains at least one selected from the group consisting of urea-modified furan resins, furan carbinol condensates, and condensates of furan carbinol and aldehydes; and co-condensates of two or more selected from these.

[0040] As the aldehydes, formaldehyde, acetaldehyde, glyoxal, furfural, terephthalaldehyde, hydroxymethylfurfural, etc. can be mentioned, and one or more of these can be used appropriately. From the viewpoint of improving mold strength, formaldehyde is preferably used, and from the viewpoint of reducing the amount of formaldehyde generated during molding, furfural, terephthalaldehyde, and hydroxymethylfurfural are preferably used.

[0041] Examples of the phenols include phenol, cresol, resorcinol, bisphenol A, bisphenol C, bisphenol E, and bisphenol F, and one or more of these may be used.

[0042] The furan resin can be produced by a known method. For example, when the furan resin is a urea-modified furan resin, the urea-modified furan resin can be obtained by reacting 100 parts by mass of furan alcohol with 0.6 to 30 parts by mass of urea and 0.4 to 50 parts by mass of paraformaldehyde using phosphoric acid as an acid catalyst.

[0043] The furan resins selected from the group consisting of:

[0044] At least one selected from the group consisting of the above-mentioned urea-modified furan resin, furan methanol condensate, and furan methanol and aldehyde condensate; and

[0045] A co-condensate of two or more selected from these

[0046] The total content of one or more of the above is preferably 90% by mass or more, more preferably 95% by mass or more, further preferably 98% by mass or more, further preferably substantially 100% by mass, and further preferably 100% by mass, in terms of reducing the content of furan carbinol in the binder composition for mold making and greatly improving the strength of the mold. It should be noted that in this specification, the so-called "substantially" refers to an amount that optionally contains impurities.

[0047] Regarding the content of the above-mentioned furan resin in the above-mentioned binder composition, from the perspective of increasing the crosslinking density of the resin and increasing the mold strength, it is preferably 20% by mass or more, more preferably 30% by mass or more, and further preferably 40% by mass or more. Regarding the content of the above-mentioned furan resin in the above-mentioned binder composition, from the perspective of maintaining good mixing properties with refractory aggregates and suppressing the decrease in mold strength, it is preferably 60% by mass or less, more preferably 50% by mass or less, and further preferably 40% by mass or less. It should be noted that the content of the above-mentioned furan resin in the above-mentioned binder composition can be measured using the method described in the examples.

[0048] [water]

[0049] About the content of the water in the above-mentioned binder composition, with respect to the viewpoint of improving mold strength, it is below 30 mass %, preferably below 25 mass %. About the content of the water in the above-mentioned binder composition, with respect to the viewpoint of regulating the viscosity of the above-mentioned binder composition, it is preferably above 5 mass %, more preferably above 8 mass %, further preferably above 10 mass %. It should be noted that the content of the water in the above-mentioned binder composition can be measured using the method described in the embodiment.

[0050] [Phosphate]

[0051] The phosphate in the binder composition is a product obtained by neutralizing phosphoric acid used as an acid catalyst when manufacturing the furan resin. The phosphate includes amine phosphate. The amine constituting the amine phosphate preferably includes one or more selected from alkylamines, alkanolamines, arylamines and arylalkylamines from the viewpoint of suppressing the generation of precipitates.

[0052] Examples of the alkylamine include ethylamine, diethylamine, triethylamine, butylamine, dibutylamine, tributylamine, octylamine, dioctylamine, trioctylamine, dodecylamine, didodecylamine, tridodecylamine, stearylamine, and distearylamine.

[0053] Examples of the alkanolamine include monoethanolamine, monoisopropanolamine, diethanolamine, diisopropanolamine, di-2-hydroxybutylamine, N-methylethanolamine, N-ethylethanolamine, triethanolamine, and triisopropanolamine.

[0054] Examples of the arylamine include aniline, and examples of the aralkylamine include benzylamine and dibenzylamine.

[0055] The phosphate may include a metal amine phosphate. The metal element constituting the metal amine phosphate preferably includes one or more selected from alkali metal elements such as sodium and potassium and alkaline earth metal elements such as magnesium and calcium.

[0056] The content of the alkali component constituting the phosphate in the binder composition by neutralization is preferably 1 mol or more, more preferably 2.5 mol or more, and further preferably 3 mol or more, relative to 1 mol of phosphoric acid, from the viewpoint of suppressing the increase in viscosity during storage. The content of the alkali component constituting the phosphate in the binder composition is preferably 3.5 mol or less, more preferably 3 mol or less, relative to 1 mol of phosphoric acid, from the viewpoint of suppressing the decrease in the curing speed during the curing of the mold.

[0057] The content of the amine in the alkaline component constituting the phosphate is preferably 0.5 mol or more, and more preferably 1 mol or more, relative to 1 mol of phosphoric acid, from the viewpoint of suppressing the generation of precipitates.

[0058] The content of the metal element in the alkaline component constituting the phosphate is preferably 0.5 mol or less, and more preferably 0.3 mol or less, relative to 1 mol of phosphoric acid, from the viewpoint of suppressing the generation of precipitates.

[0059] Regarding the content of the above-mentioned phosphate in the above-mentioned binder composition, from the viewpoint of shortening the manufacturing time of the binder composition, it is preferably converted into phosphoric acid to be 0.1% by mass or more, more preferably 0.3% by mass or more, and further preferably 0.5% by mass or more. Regarding the content of the above-mentioned phosphate in the above-mentioned binder composition, from the viewpoint of reducing the viscosity of the binder composition, it is preferably converted into phosphoric acid to be 2% by mass or less, more preferably 1% by mass or less, and further preferably 0.5% by mass or less.

[0060] In addition, the average molecular weight of the phosphate calculated from the amount of phosphoric acid added and the type and amount of the alkali added is preferably 150 or more, more preferably 200 or more, from the viewpoint of suppressing the viscosity increase during storage. The average molecular weight of the phosphate is preferably 2000 or less, more preferably 1500 or less, from the viewpoint of suppressing the decrease in mold strength.

[0061] Regarding the content of the above-mentioned phosphate in the above-mentioned binder composition relative to the solid content other than water and solvent, from the viewpoint of shortening the manufacturing time of the binder composition, it is preferably converted into phosphoric acid to be 0.4% by mass or more, and more preferably 0.6% by mass or more. Regarding the content of the above-mentioned phosphate in the above-mentioned binder composition, from the viewpoint of reducing the viscosity of the binder composition, it is preferably converted into phosphoric acid to be 2.5% by mass or less, more preferably 1.3% by mass or less, and further preferably 0.7% by mass or less.

[0062] [other]

[0063] [Bis(hydroxymethyl)furan]

[0064] The binder composition preferably contains bishydroxymethylfuran from the viewpoint of reducing the furanol content and improving the mold strength, and from the viewpoint of lowering the viscosity.

[0065] The bishydroxymethylfuran preferably contains one or more selected from 2,5-bishydroxymethylfuran and 3,4-bishydroxymethylfuran, and more preferably contains 2,5-bishydroxymethylfuran.

[0066] About the content of bishydroxymethylfuran in the above-mentioned binder composition, from the viewpoint of reducing furan methanol content and improving mold strength and the viewpoint of low viscosity, preferably 5 mass % or more, more preferably 10 mass % or more, more preferably 12 mass % or more, and more preferably 15 mass % or more. About the content of bishydroxymethylfuran in the above-mentioned binder composition, from the viewpoint of improving storage stability, preferably 35 mass % or less, more preferably 30 mass % or less, more preferably 25 mass % or less, and more preferably 20 mass % or less. It should be noted that the content of bishydroxymethylfuran can be measured by the method described in the embodiment.

[0067] [Curing accelerator]

[0068] From the viewpoint of improving the strength of the mold, the binder composition may contain a curing accelerator. As the curing accelerator, from the viewpoint of improving the strength of the mold, it is preferred that the curing accelerator is one or more selected from urea and urea derivatives, phenol derivatives, aromatic dialdehydes, and tannins.

[0069] The urea and urea derivatives mentioned above refer to urea and urea derivatives that have not undergone condensation reaction with formaldehyde, furanol, etc., and may be urea and urea derivatives remaining as unreacted components or urea and urea derivatives added separately.

[0070] As urea and urea derivatives in the above-mentioned binder composition, for example, there can be mentioned: urea; alkylene ureas such as ethylene urea, propylene urea, butylene urea, and hydantoin; alkyl ureas such as methyl urea, 1,1-dimethyl urea, and 1,3-dimethyl urea; cyclohexyl ureas such as cyclohexyl urea and 1,3-dicyclohexyl urea; aryl ureas such as phenyl urea, 1,1-diphenyl urea, and 1,3-diphenyl urea; hydroxyalkyl ureas such as 2-hydroxyethyl urea having an alkyl group with a carbon number of 2 or more; azodicarbonamide, etc. These compounds can be used alone or in combination of two or more. From the viewpoint of increasing the curing speed, increasing the mold strength, and reducing the amount of formaldehyde generated, urea and ethylene urea are preferred, and from the viewpoint of economic efficiency, urea is more preferred.

[0071] When the binder composition contains urea and urea derivatives, the content thereof is preferably 0.5% by mass or more, more preferably 1% by mass or more, and further preferably 1.5% by mass or more, from the viewpoint of improving the strength of the mold, reducing the formaldehyde concentration in the binder composition and the amount of formaldehyde released from the mold during casting. The content of the urea in the binder composition is preferably 8% by mass or less, more preferably 7% by mass or less, and further preferably 6% by mass or less, from the viewpoint of improving the strength of the mold and the storage stability of the binder composition.

[0072] Examples of the phenol derivatives include resorcinol, cresol, hydroquinone, phloroglucinol, methylene bisphenol, etc. When the binder composition contains the phenol derivatives, the content thereof is preferably 1 to 25% by mass, more preferably 2 to 15% by mass, and further preferably 3 to 10% by mass from the viewpoint of improving mold strength.

[0073] As the above-mentioned aromatic dialdehyde, there can be mentioned: terephthalaldehyde, o-phthalaldehyde and isophthalaldehyde, and their derivatives. Their derivatives refer to compounds having substituents such as alkyl groups on the aromatic ring of an aromatic compound having two formyl groups as a basic skeleton. When the above-mentioned binder composition contains an aromatic dialdehyde, its content is preferably 0.1 to 15% by mass, more preferably 0.5 to 10% by mass, and further preferably 1 to 5% by mass from the viewpoint of fully dissolving the aromatic dialdehyde in the furan resin and suppressing the odor of the aromatic dialdehyde itself.

[0074] As the above-mentioned tannins, condensed tannins or hydrolyzed tannins can be cited. As examples of these condensed tannins or hydrolyzed tannins, tannins having a pyrogallol skeleton and a resorcinol skeleton can be cited. In addition, bark extracts containing these tannins, extracts obtained from natural materials such as plant leaves, fruits, seeds, and galls parasitic on plants can be added. In the case where tannins are contained in the above-mentioned binder composition, the content thereof is preferably 0.2 to 10% by mass, more preferably 1.0 to 7% by mass, and further preferably 1.9 to 5% by mass from the viewpoint of increasing the curing speed and the viewpoint of increasing the mold strength.

[0075] The above-mentioned binder composition may also contain additives such as silane coupling agents. For example, if the above-mentioned binder composition contains a silane coupling agent, the final strength of the obtained casting mold can be further improved, so it is preferred. As a silane coupling agent, aminosilanes such as N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropylmethyldimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropyltriethoxysilane, urea silane, mercaptosilane, thioether silane, methacryloxysilane, acryloxysilane, etc. can be used. Preferably, it contains one or more selected from aminosilane, epoxysilane and ureidosilane, and more preferably contains one or more selected from aminosilane and epoxysilane. The aminosilane preferably contains N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane. The epoxysilane preferably contains 3-glycidyloxypropylmethyldimethoxysilane.

[0076] When the above-mentioned adhesive composition contains a silane coupling agent, its content is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and further preferably 0.2% by mass or more from the viewpoint of improving mold strength. The content of the silane coupling agent in the above-mentioned adhesive composition is preferably 5% by mass or less, more preferably 3% by mass or less, further preferably 1% by mass or less, and further preferably 0.5% by mass or less from the same viewpoint.

[0077] The binder composition for mold making of the present embodiment is suitable for mold making of self-hardening molds. Here, the self-hardening mold refers to a mold in which, when the binder composition and the curing agent are mixed in the sand, a polymerization reaction is carried out over time, and the mold is cured. The temperature of the sand used at this time is in the range of -20°C to 50°C, preferably 0°C to 40°C. For sand at this temperature, a curing agent suitable for the amount is selected and added to the sand, so that the mold can be suitably cured.

[0078] <Molding composition>

[0079] The casting mold composition of the present embodiment contains the above-mentioned binder composition and a curing agent composition containing a curing agent for curing the casting mold composition. The casting mold composition of the present embodiment has the same effects as the above-mentioned binder composition.

[0080] [Curing agent composition]

[0081] As long as the curing agent composition contains a curing agent that cures the binder composition, it can be used without particular limitation. As the curing agent, an acid curing agent can be exemplified, and one or more of the curing agents known in the past such as sulfonic acid compounds such as xylenesulfonic acid (especially m-xylenesulfonic acid), toluenesulfonic acid (especially p-toluenesulfonic acid), methanesulfonic acid, phosphoric acid, acidic phosphate esters, and sulfuric acid can be used. With regard to these compounds, from the viewpoint of operability, aqueous solutions are preferably used. Furthermore, the curing agent composition can contain one or more solvents and carboxylic acids selected from alcohols, ether alcohols, and esters.

[0082] The content of the above-mentioned solvent in the above-mentioned curing agent composition can be appropriately adjusted according to the temperature of the working environment and the temperature of the refractory particles to obtain the desired reaction speed and mold strength. Generally speaking, from the perspective of dissolving the curing agent composition, it is preferably 5% by mass or more, more preferably 10% by mass or more, and more preferably 20% by mass or more. Regarding the content of the above-mentioned solvent in the above-mentioned curing agent composition, from the perspective of improving mold strength, it is preferably 90% by mass or less, more preferably 80% by mass or less, and more preferably 70% by mass or less.

[0083] The content of the curing agent in the curing agent composition is preferably 10% by mass or more, more preferably 20% by mass or more, and further preferably 30% by mass or more, from the viewpoint of improving the strength of the mold. The content of the curing agent in the curing agent composition is preferably 95% by mass or less, more preferably 90% by mass or less, and further preferably 80% by mass or less, from the viewpoint of dissolving the curing agent composition.

[0084] Regarding the mass ratio of the above-mentioned adhesive composition to the above-mentioned curing agent, from the viewpoint of increasing the curing speed and improving the mold strength, the above-mentioned curing agent is preferably 10 to 60 parts by mass, more preferably 10 to 40 parts by mass, and further preferably 10 to 30 parts by mass relative to 100 parts by mass of the above-mentioned adhesive composition.

[0085] [Mold composition]

[0086] The casting composition of this embodiment contains refractory particles, the above-mentioned binder composition, and the above-mentioned curing agent composition. The casting composition of this embodiment has the same effects as the above-mentioned binder composition.

[0087] [Refractory particles]

[0088] As the refractory particles, one or more of the refractory particles known in the past such as silica sand, chrome sand, zircon sand, olivine sand, alumina sand, mullite sand, synthetic mullite sand can be used, and in addition, the refractory particles used can be recovered or regenerated, etc. Among these, silica sand is preferably included.

[0089] In the above-mentioned casting mold composition, the mass ratio of the above-mentioned refractory particles, the above-mentioned binder composition, and the above-mentioned curing agent can be appropriately set. From the viewpoint of increasing the curing speed and improving the casting mold strength, relative to 100 parts by mass of the above-mentioned refractory particles, the above-mentioned binder composition is preferably 0.5 to 1.5 parts by mass, and the above-mentioned curing agent is preferably in the range of 0.07 to 1 part by mass.

[0090] <Method for manufacturing casting mold>

[0091] The method for manufacturing a mold of the present embodiment includes: a mixing step of mixing refractory particles, the binder composition and the curing agent composition to obtain a mold composition; and a curing step of filling the mold composition in a mold frame and curing the mold composition. The method for manufacturing a mold has the same effect as the binder composition.

[0092] In the above-mentioned mixing process, the order of adding and mixing the above-mentioned binder composition, the above-mentioned curing agent composition and the refractory particles is not particularly limited. After the above-mentioned binder composition and the above-mentioned curing agent composition are mixed to manufacture the composition for mold making, the composition for mold making and the refractory particles are mixed. The above-mentioned binder composition, the above-mentioned curing agent composition and the refractory particles can also be added and mixed respectively. From the perspective of storage stability and the productivity of the mold, the above-mentioned binder composition, the above-mentioned curing agent composition and the refractory particles are preferably mixed to obtain the composition for mold. In addition, from the perspective of improving the strength of the mold, it is preferred to add the curing agent composition to the refractory particles and mix, then add the binder composition and mix. In addition, when using more than two curing agent compositions, each curing agent composition can be added after mixing, or each curing agent composition can be added respectively.

[0093] In the mixing step, as a method for mixing the raw materials, a known general method can be used, and examples thereof include a method of adding and kneading the raw materials using a batch mixer, and a method of supplying and kneading the raw materials to a continuous mixer.

[0094] In the method for manufacturing a casting mold according to the present embodiment, the casting mold can be manufactured by utilizing the conventional casting mold manufacturing process as it is, except for the mixing step.

[0095] <Manufacturing method of casting>

[0096] The method for manufacturing a casting of the present embodiment includes: a mold manufacturing step, which manufactures a mold by the above-mentioned method for manufacturing a mold; and a casting step, which uses the mold obtained in the above-mentioned mold manufacturing step to cast metal. The above-mentioned casting step optionally includes: a casting step, which injects molten metal into the above-mentioned mold; and a cooling step, which cools the above-mentioned molten metal injected into the above-mentioned mold after the above-mentioned casting step. In addition, the method for manufacturing a casting of the present embodiment optionally includes: a mold removal step, which removes the above-mentioned mold to take out the casting after the above-mentioned cooling step. In the above-mentioned mold removal step, as a method for removing the above-mentioned mold, for example, a method of disassembling the above-mentioned mold can be cited. Regarding the manufacture of the casting of the present embodiment, the casting can be manufactured using a conventional casting manufacturing process.

[0097] Regarding the above-mentioned embodiment, this specification further discloses the following composition, production method, etc.

[0098] <1>

[0099] A binder composition for casting molds, comprising furan carbinol, furan resin, water and phosphate, and satisfying the following conditions (1) to (4).

[0100] Condition (1): The content of furanol in the above-mentioned binder composition for casting mold making is more than 0 mass % and is 30 mass % or less;

[0101] Condition (2): The content of the furan resin in the binder composition for casting mold making is 20% by mass or more and 60% by mass or less;

[0102] Condition (3): The water content in the above-mentioned binder composition for casting mold making is 5 mass % or more and 30 mass % or less;

[0103] Condition (4): The phosphate salt comprises amine phosphate.

[0104] <2>

[0105] The binder composition for casting mold making as described in the above <1>, wherein the content of furanol in the binder composition for casting mold making is preferably 25% by mass or less, and more preferably 5% by mass or more.

[0106] <3>

[0107] A binder composition for casting mold making as described in <1> or <2> above, wherein the furan resin preferably contains one or more selected from the following substances: a condensation product of furan methanol and urea, a condensation product of furan methanol and melamine, a condensation product of furan methanol and ethylene urea, a condensation product of furan methanol and urea and aldehydes (urea-modified furan resin), a condensation product of furan methanol and melamine and aldehydes, a condensation product of furan methanol and ethylene urea and aldehydes, a condensation product of furan methanol, a condensation product of furan methanol and aldehydes, and a condensation product of furan methanol and phenols and aldehydes; and a co-condensation product of two or more selected from them.

[0108] <4>

[0109] The binder composition for casting mold making as described in <3>, wherein the total content of one or more selected from the above furan resins is preferably 90% by mass or more:

[0110] One or more selected from the group consisting of the above-mentioned urea-modified furan resins, furan methanol condensates, and condensates of furan methanol and aldehydes; and co-condensates of two or more selected from these.

[0111] <5>

[0112] The binder composition for casting mold making as described in any one of <1> to <4>, wherein the content of the furan resin in the binder composition for casting mold making is preferably 20% by mass or more and preferably 60% by mass or less.

[0113] <6>

[0114] The binder composition for casting mold making as described in any one of <1> to <5>, wherein the content of water in the binder composition for casting mold making is 30% by mass or less, preferably 5% by mass or more.

[0115] <7>

[0116] A binder composition for casting mold making as described in any one of <1> to <6>, wherein the phosphate in the binder composition for casting mold making comprises amine phosphate, and the amine constituting the amine phosphate preferably comprises one or more selected from alkylamines, alkanolamines, arylamines and arylalkylamines.

[0117] <8>

[0118] The binder composition for casting mold making as described in <7>, wherein the above-mentioned alkylamine preferably contains one or more selected from ethylamine, diethylamine, triethylamine, butylamine, dibutylamine, tributylamine, octylamine, dioctylamine, trioctylamine, dodecylamine, didodecylamine, tridodecylamine, stearylamine and distearylamine.

[0119] <9>

[0120] The binder composition for casting mold making as described in <7> or <8>, wherein the alkanolamine preferably includes one or more selected from monoethanolamine, monoisopropanolamine, diethanolamine, diisopropanolamine, di-2-hydroxybutylamine, N-methylethanolamine, N-ethylethanolamine, triethanolamine and triisopropanolamine.

[0121] <10>

[0122] In the binder composition for casting mold making as described in any one of <7> to <9>, the arylamine preferably contains aniline.

[0123] <11>

[0124] In the binder composition for casting mold making as described in any one of <7> to <10>, the aralkylamine preferably includes one or more selected from benzylamine and dibenzylamine.

[0125] <12>

[0126] In the binder composition for casting mold making as described in any one of <1> to <11>, the phosphate preferably comprises a metal amine phosphate.

[0127] <13>

[0128] In the binder composition for casting mold making as described in <12>, the metal element constituting the metal amine phosphate preferably includes one or more selected from alkali metal elements such as sodium and potassium and alkaline earth metal elements such as magnesium and calcium.

[0129] <14>

[0130] The binder composition for casting mold making as described in any one of <1> to <13>, wherein the content of the alkali component constituting the phosphate by neutralization in the binder composition for casting mold making is preferably 1 mol or more and preferably 3.5 mol or less relative to 1 mol of phosphoric acid.

[0131] <15>

[0132] The binder composition for casting mold making as described in any one of <1> to <14>, wherein the content of the amine in the alkaline component constituting the phosphate is preferably 0.5 mol or more per mol of phosphoric acid.

[0133] <16>

[0134] The binder composition for casting mold making as described in any one of <1> to <15>, wherein the content of the metal element in the alkali component constituting the phosphate is preferably 0.5 mol or less per mol of phosphoric acid.

[0135] <17>

[0136] The binder composition for casting mold making as described in any one of <1> to <16>, wherein the content of the phosphate in the binder composition for casting mold making is preferably 0.1 mass % or more and preferably 2 mass % or less in terms of phosphoric acid.

[0137] <18>

[0138] The binder composition for casting mold making as described in any one of <1> to <17>, wherein the average molecular weight of the phosphate calculated from the amount of phosphoric acid added and the type and amount of the alkali added is preferably 150 or more and preferably 2000 or less.

[0139] <19>

[0140] The binder composition for casting mold making as described in any one of <1> to <18>, wherein the content of the phosphate in the binder composition for casting mold making is preferably 0.4 mass % or more and preferably 2.5 mass % or less relative to the solid content excluding water and the solvent, calculated as phosphoric acid.

[0141] <20>

[0142] The binder composition for casting mold making as described in any one of <1> to <19>, wherein the binder composition for casting mold making preferably contains bishydroxymethylfuran.

[0143] <21>

[0144] The binder composition for casting mold making as described in <20>, wherein the bishydroxymethylfuran preferably contains one or more selected from 2,5-bishydroxymethylfuran and 3,4-bishydroxymethylfuran.

[0145] <22>

[0146] The binder composition for casting mold making as described in <20> or <21>, wherein the content of bishydroxymethylfuran in the binder composition for casting mold making is preferably 5 mass % or more and preferably 35 mass % or less.

[0147] <23>

[0148] The binder composition for casting mold making as described in any one of <1> to <22>, wherein the binder composition for casting mold making preferably contains a silane coupling agent.

[0149] <24>

[0150] The binder composition for casting mold making as described in <23>, wherein the silane coupling agent preferably includes one or more selected from aminosilane, epoxysilane, ureidosilane, mercaptosilane, sulfide silane, methacryloxysilane and acryloxysilane.

[0151] <25>

[0152] An adhesive composition for casting mold making as described in <23> or <24>, wherein the above-mentioned aminosilane preferably contains one or more selected from N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropyltriethoxysilane and 3-aminopropyltrimethoxysilane.

[0153] <26>

[0154] The binder composition for casting mold making as described in any one of <23> to <25>, wherein the epoxysilane preferably includes one or more selected from 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropylmethyldimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane and 3-glycidyloxypropyltriethoxysilane.

[0155] <27>

[0156] The binder composition for casting mold making as described in any one of <23> to <26>, wherein the content of the silane coupling agent in the binder composition for casting mold making is preferably 0.01 mass % or more and preferably 5 mass % or less.

[0157] <28>

[0158] A casting mold molding composition comprising the casting mold molding binder composition as described in any one of <1> to <27> and a curing agent composition containing a curing agent for curing the casting mold molding binder composition.

[0159] <29>

[0160] A casting mold composition comprising refractory particles, the casting mold binder composition as described in any one of <1> to <27>, and a curing agent composition.

[0161] <30>

[0162] A method for manufacturing a casting mold, comprising: a mixing step of mixing refractory particles, a binder composition for casting mold making as described in any one of <1> to <27>, and the above-mentioned curing agent composition to obtain a casting mold composition; and a curing step of filling the above-mentioned casting mold composition into a mold frame and curing the casting mold composition.

[0163] <31>

[0164] A method for producing a casting, comprising: a mold producing step of producing a mold by the method for producing a mold as described in <30>; and a casting step of casting a metal using the mold obtained in the mold producing step.

[0165] <32>

[0166] The method for producing a casting as described in <31>, wherein the casting step includes: a casting step of pouring molten metal into the casting mold; and a cooling step of cooling the molten metal poured into the casting mold after the casting step.

[0167] <33>

[0168] The method for producing a casting as described in <32> includes: a mold removing step of removing the mold to take out the casting after the cooling step.

[0169] <34>

[0170] A casting mold produced by the method for producing a casting mold as described in <30>.

[0171] <35>

[0172] Use of the composition according to any one of <1> to <27> as a binder composition for casting mold making.

[0173] [Example]

[0174] <Measurement methods of physical properties>

[0175] [Water content]

[0176] The measurement was performed using an automatic water content meter (manufactured by Hiranuma Sangyo Co., Ltd., AQV-2200A) in accordance with the Karl Fischer method specified in JIS K 0068.

[0177] [Content of furanol and bis(hydroxymethylfuran)]

[0178] The measurement was performed by gas chromatography analysis under the following conditions using a gas chromatograph (GC-2014S manufactured by Shimadzu Corporation).

[0179] ・Measurement sample dilution solvent: Methanol

[0180] ・Standard curve: Using 1,6-hexanediol as the internal standard, prepare the standard curves of furanol and bis(hydroxymethylfuran).

[0181] ・Column: PEG-20M Chromosorb WAW DMCS 60 / 80mesh (manufactured by GL Sciences Co., Ltd.)

[0182] ・Column temperature: 80~200℃(8℃ / min)

[0183] ・Injection temperature: 210℃

[0184] ・Detector temperature: 250℃ Carrier gas: 50 mL / min (He)

[0185] [Viscosity]

[0186] The viscosity was measured using an E-type viscometer (RE-80R, manufactured by Toki Sangyo Co., Ltd.) at 25° C. and a rotation speed of 100 rpm using a standard rotor (cone angle 1°34′, cone radius: 24 mm).

[0187] <Method for producing adhesive composition>

[0188] [Example 1]

[0189] Into a three-necked flask equipped with a stirrer, a condenser and a thermometer, 555.50 g of furan methanol, 4.13 g of triethylamine, 5.88 g of an 85% by mass phosphoric acid aqueous solution and 157.10 g of 92% by mass paraformaldehyde were added while stirring. The triethylamine was 0.8 moles per 1 mole of phosphoric acid. The reaction was carried out at 100°C until the furan methanol monomer became 33% by mass. Thereafter, 38.12 g of urea was added and reacted at 105°C for 1 hour. Thereafter, it was cooled to 70°C with air, 18.66 g of urea was added, and the reaction was carried out at 70°C for 20 minutes to obtain a reaction product containing urea-modified furan resin. The obtained reaction product was analyzed, and the result was that furan methanol was 19.2% by mass, 2,5-bishydroxymethylfuran was 20.5% by mass, and water was 9.73% by mass. In addition, the amount of furan resin (urea-modified furan resin) is the remaining amount after deducting furan methanol, 2,5-bishydroxymethyl furan, water and the calculated amount of phosphate from the obtained reaction product. Based on the analysis results, the amount of furan methanol and water is calculated so that the content of furan methanol in the adhesive composition is 19% by mass, the content of furan resin (urea-modified furan resin) is 35.45% by weight, and the content of water is 24% by mass. In addition, the amount of triethylamine in an amount of 3 moles relative to 1 mole of phosphoric acid in the adhesive composition is calculated. 40.00 g of furan methanol, 164.26 g of water, 11.36 g of triethylamine and 5.00 g of silane coupling agent (KBM-602 manufactured by Shin-Etsu Chemical Co., Ltd.) are added to the obtained reaction product and mixed to obtain the adhesive composition of Example 1.

[0190] [Examples 2 to 10, Comparative Examples 1 to 2]

[0191] The same method as in Example 1 was used, except that the amount of the alkali species was changed so as to obtain the amount of the phosphoric acid neutralized salt using the alkali components shown in Table 1, to obtain the binder compositions of Examples 2 to 11 and Comparative Examples 1 to 2, respectively. In Table 1, FFA refers to furanol, and BHMF refers to 2,5-bis(hydroxymethyl)furan.

[0192] [Example 11]

[0193] 531.78 g of furan methanol, 3.71 g of triethylamine, 165.17 g of 92% by mass of paraformaldehyde and 160.96 g of urea were added to a three-necked flask equipped with a stirrer, a condenser and a thermometer, and reacted for 90 minutes at normal pressure and 110°C. Thereafter, 5.27 g of 85% phosphoric acid was added, and the reaction was further reacted at 90°C for 240 minutes to obtain a reaction product. The obtained reaction product was analyzed, and as a result, furan methanol was 21.5% by mass, BHMF was 0% by mass, and water was 14.5% by mass. In addition, the amount of furan resin (urea-modified furan resin) was calculated in the same manner as in Example 1. Based on the analysis results, the amount of furan methanol and water was calculated so that the content of furan methanol in the binder composition was 19% by mass and the content of water was 24.0% by mass. In addition, the amount of triethylamine in an amount of 3 moles relative to 1 mole of phosphoric acid in the binder composition was calculated. To the obtained reaction product, 114.30 g of water, 10.17 g of triethylamine, and 5.00 g of a silane coupling agent (KBM-602 manufactured by Shin-Etsu Chemical Co., Ltd.) were added and mixed to obtain an adhesive composition of Example 11.

[0194] [Evaluation of storage stability]

[0195] 50 g of the binder composition for mold making was put into a 50 mL spiral bottle (manufactured by AS ONE Co., Ltd.) and sealed, and stored in a constant temperature room at 50 ° C. The viscosity at a time point after 30 days was measured using the above-mentioned viscosity determination method. It should be noted that in the evaluation of storage stability in Table 1, the viscosity of the "0 day" refers to the viscosity of the binder composition for mold making on the day when the binder composition for mold making was manufactured, and "30 days later" refers to the viscosity of the binder composition for mold making at a time point after 30 days. According to the viscosity of "0 day" and the viscosity of "30 days later", the rate of change of viscosity is calculated by the following formula, and the rate of change is used as an evaluation of storage stability. This evaluation is sometimes also accelerated at a temperature higher than the usual storage temperature. As long as the viscosity change rate is less than 50%, it is considered that there is no problem.

[0196] Change rate (%) = (viscosity after 30 days - viscosity on day 0) / viscosity on day 0 × 100

[0197] [Evaluation of the Presence of Precipitates]

[0198] 30 g of the binder composition for casting molds was placed in a 50 mL screw-top bottle (manufactured by AS ONE Co., Ltd.), sealed, and left to stand for 1 day. Thereafter, the presence or absence of precipitates deposited on the bottom of the screw-top bottle was visually confirmed.

[0199] [Table 1]

[0200]

Claims

1. A binder composition for casting molds, comprising furan carbinol, furan resin, water and phosphate, and satisfying the following conditions (1) to (4): Condition (1): The content of furanol in the binder composition for casting mold making is more than 0% by mass and is 30% by mass or less; Condition (2): The content of the furan resin in the binder composition for casting mold making is 20 mass % or more and 60 mass % or less; Condition (3): The water content in the binder composition for casting mold making is 5 mass % or more and 30 mass % or less; Condition (4): The phosphate comprises amine phosphate.

2. The binder composition for casting mold making according to claim 1, wherein The amine constituting the amine phosphate salt includes one or more selected from the group consisting of alkylamines, alkanolamines, arylamines, and arylalkylamines.

3. The binder composition for casting mold making according to claim 1 or 2, wherein The content of the phosphate in the binder composition for casting mold making is 0.1 mass % or more and 2 mass % or less in terms of phosphoric acid.

4. The binder composition for casting mold making according to any one of claims 1 to 3, wherein The furan resin contains one or more selected from the following substances: One or more selected from the group consisting of urea-modified furan resins, furan methanol condensates, and condensates of furan methanol and aldehydes; and co-condensates of two or more selected from these.

5. The binder composition for casting mold making according to any one of claims 1 to 4, wherein The content of the alkali component constituting the phosphate in the binder composition for casting mold making is 1 mol or more and 3.5 mol or less relative to 1 mol of phosphoric acid. 6 . A casting mold molding composition comprising the casting mold molding binder composition according to claim 1 and a curing agent composition containing a curing agent for curing the casting mold molding binder composition. 7 . A composition for a foundry mold, comprising refractory particles, the binder composition for foundry mold making according to claim 1 , and a curing agent composition containing a curing agent for curing the binder composition for foundry mold making.

8. A method for manufacturing a casting mold, comprising: a mixing step of mixing refractory particles, the binder composition for casting mold making according to any one of claims 1 to 5, and a curing agent composition containing a curing agent for curing the binder composition for casting mold making to obtain a casting mold composition; and The step of curing is to fill the mold composition in a mold frame and cure the mold composition.

9. A method for manufacturing a casting, comprising: a casting mold manufacturing step of manufacturing the casting mold by the casting mold manufacturing method according to claim 8; and A casting step is to cast metal using the casting mold obtained in the casting mold manufacturing step.

10. A casting mold produced by the method for producing a casting mold according to claim 8.

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