JP7102639B1 - Binder composition for mold molding - Google Patents

Abstract

The present invention contains furfuryl alcohol (Component A), bishydroxymethylfuran (Component B), resin (Component C) and water (Component D), and molds that satisfy the following conditions (1) to (5): It is a binder composition for Condition (1): The content of Component A in the binder composition for mold making is 30.0% by mass or less Condition (2): The content of Component D in the binder composition for mold making The amount is 25.0% by mass or less Condition (3): The content of the component B is 39.0% by mass or more with respect to the total content of the component B and the component C in the binder composition for mold making 95.0% by mass or less Condition (4): The nitrogen content in component C is 2.7% by mass or more and 22.0% by mass or less Condition (5): The component in the binder composition for mold making When the content of B is y and the nitrogen content of the component C is x, 2.97x + 15.2 ≤ y that satisfies the following formula (1) (1) According to the present invention, mold strength in a low temperature environment It is possible to provide a binder composition with a low content of monomeric furfuryl alcohol that can greatly improve the

Description

The present invention relates to a binder composition for molding.

In general, an acid-curable mold comprises a binder composition for molding containing an acid-curable resin and a curing agent composition containing sulfonic acid, sulfuric acid, phosphoric acid, etc. in fire-resistant particles such as silica sand. After adding and kneading these, the obtained kneaded sand is filled in a prototype such as a wooden mold, and the acid-curable resin is cured to produce the product. Furan resin, phenol resin, etc. are used as the acid curable resin, and furfuryl alcohol / urea / formaldehyde resin, furfuryl alcohol / formaldehyde resin, furfuryl alcohol / phenol / formaldehyde resin, etc. are used as the furan resin. A known modified furan resin or the like is used. Such a mold manufacturing method enables molding work with a high degree of freedom, and since high-quality castings can be manufactured due to the excellent thermal properties of the mold, machine parts, construction machine parts, automobile parts, etc. Widely used in casting castings.

One of the important conditions in manufacturing a mold is to improve the working environment during mold manufacturing (during resin curing), and in particular, to reduce the amount of furfuryl alcohol that volatilizes during mold manufacturing, furan resin. It is desired to reduce the monomeric furfuryl alcohol inside.

For example, Japanese Patent Application Laid-Open No. 2014-501175 states that the release of furfuryl alcohol and formaldehyde during kneading and molding can be reduced by using a binder composition having a low content of monomeric furfuryl alcohol. Is disclosed.

Further, in Japanese Patent Application Laid-Open No. 56-61420, a mold molding in which a high proportion of furfuryl alcohol skeleton is introduced into the resin structure and the content of monomeric furfuryl alcohol is low by sufficiently carrying out the reaction. A method for producing a phenol-furfuryl alcohol-formaldehyde resin for use is disclosed.

Further, in Japanese Patent Application Laid-Open No. 2013-151019, the same pot life can be obtained by using a binder composition containing 5-hydroxymethylfurfural or 2,5-bishydroxymethylfuran as an alternative to furfuryl alcohol. It is disclosed that by shortening the die-cutting time, the mold productivity can be improved, and the curing speed and the mold strength can be improved.

The present invention contains furfuryl alcohol (component A), bishydroxymethylfuran (component B), resin (component C) and water (component D).
A binder composition for molding that satisfies the following conditions (1) to (5).
Condition (1): The content of the component A in the mold-molding binder composition is 30.0% by mass or less Condition (2): The content of the component D in the mold-molding binder composition Condition (3): The content of the component B is 39.0% by mass or more with respect to the total content of the component B and the component C in the binder composition for molding. 95.0% by mass or less Condition (4): Nitrogen content in the component C is 2.7% by mass or more and 22.0% by mass or less Condition (5): The component in the mold-molding binder composition When the content of B is y and the nitrogen content of the component C is x, the following formula (1) is satisfied. 2.97x + 15.2 ≦ y (1)

Further, the present invention is a mold molding composition containing the mold molding binder composition and a curing agent composition containing a curing agent for curing the mold molding binder composition. ..

Further, the present invention is for a mold, which comprises refractory particles, the binder composition for molding, and a curing agent composition containing a curing agent for curing the binder composition for molding. It is a composition.

Further, in the present invention, the fire-resistant particles, the binder composition for molding, and the curing agent composition containing a curing agent for curing the binder composition for molding are mixed and used for a mold. A method for producing a mold, which comprises a mixing step of obtaining a composition and a curing step of packing the mold composition in a mold and curing the mold composition.

Detailed description of the invention

The conventionally proposed binder composition having a low content of monomeric furfuryl alcohol has insufficient template strength, especially the template strength in a low temperature (for example, 5 ° C or lower) environment, and is improved. There was room.

INDUSTRIAL APPLICABILITY The present invention can significantly improve the mold strength in a low temperature environment, and has a low content of monomeric furfuryl alcohol, a mold-molding binder composition, a mold-molding composition, and a mold composition. A method for manufacturing a product and a mold is provided.

The present invention contains furfuryl alcohol (component A), bishydroxymethylfuran (component B), resin (component C) and water (component D).
A binder composition for molding that satisfies the following conditions (1) to (5).
Condition (1): The content of the component A in the mold-molding binder composition is 30.0% by mass or less Condition (2): The content of the component D in the mold-molding binder composition Condition (3): The content of the component B is 39.0% by mass or more with respect to the total content of the component B and the component C in the binder composition for molding. 95.0% by mass or less Condition (4): Nitrogen content in the component C is 2.7% by mass or more and 22.0% by mass or less Condition (5): The component in the mold-molding binder composition When the content of B is y and the nitrogen content of the component C is x, the following formula (1) is satisfied. 2.97x + 15.2 ≦ y (1)

Further, the present invention is a mold molding composition containing the mold molding binder composition and a curing agent composition containing a curing agent for curing the mold molding binder composition. ..

Further, the present invention is for a mold, which comprises refractory particles, the binder composition for molding, and a curing agent composition containing a curing agent for curing the binder composition for molding. It is a composition.

Further, in the present invention, the fire-resistant particles, the binder composition for molding, and the curing agent composition containing a curing agent for curing the binder composition for molding are mixed and used for a mold. A method for producing a mold, which comprises a mixing step of obtaining a composition and a curing step of packing the mold composition in a mold and curing the mold composition.

According to the present invention, a mold-molding binder composition, a mold-molding composition, and a mold, which can significantly improve the mold strength in a low-temperature environment and have a low content of monomeric furfuryl alcohol. A method for producing a composition for mold and a mold can be provided.

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

<Caking agent composition for molding>
The binder composition for molding of the present embodiment (hereinafter, also simply referred to as a binder composition) includes furfuryl alcohol (component A), bishydroxymethylfuran (component B), resin (component C), and water. It contains (component D) and satisfies the following conditions (1) to (5).
Condition (1): The content of the component A in the mold-molding binder composition is 30.0% by mass or less Condition (2): The content of the component D in the mold-molding binder composition Condition (3): The content of the component B is 39.0% by mass or more with respect to the total content of the component B and the component C in the binder composition for molding. 95.0% by mass or less Condition (4): Nitrogen content in the component C is 2.7% by mass or more and 22.0% by mass or less Condition (5): The component in the mold-molding binder composition When the content of B is y and the nitrogen content of the component C is x, the following formula (1) is satisfied. 2.97x + 15.2 ≦ y (1)

According to the binder composition, it is possible to provide a binder composition having a low content of monomeric furfuryl alcohol, which can significantly improve the template strength in a low temperature environment. The reason why the binder composition exerts such an effect is not clear, but it is considered as follows.

Bishydroxymethylfuran (component B) is superior in reactivity with furfuryl alcohol (component A) as compared with the resin (component C), and reduces the viscosity of the binder composition. When the content of bishydroxymethylfuran (component B) is increased, the reactivity is improved, the viscosity of the binder composition is also reduced, and the kneadability with the refractory particles is also improved, so that the mold strength is improved. On the other hand, since bishydroxymethylfuran (component B) has a high melting point, the storage stability deteriorates as the content increases (condition (3)). Further, when the nitrogen content in the resin is increased, the crosslinking reaction proceeds and the mold strength is improved. On the other hand, when the nitrogen content in the resin increases, the viscosity of the binder composition increases, the kneadability with the refractory particles deteriorates, and the strength decreases (condition (4)). Therefore, as the nitrogen content in the resin increases, the content of bishydroxymethylfuran (component B) is increased with respect to the total content of bishydroxymethylfuran (component B) and the resin (component C) to lower the viscosity. Therefore, it is considered that the mold strength can be improved (condition (5)).

[Furfuryl alcohol (ingredient A)]
The content of the component A in the binder composition is 30.0% by mass or less, preferably 25.0% by mass or less, more preferably 20.0% by mass or less, from the viewpoint of improving the working environment. It is preferable, and 15.0% by mass or less is more preferable. The content of the component A in the binder composition is preferably more than 0% by mass, more preferably 5.0% by mass or more, still more preferably 10.0% by mass or more, from the viewpoint of improving the template strength. 15.0% by mass or more is more preferable, and 20.0% by mass or more is even more preferable. The content of component A can be measured by the method described in Examples.

[Bishydroxymethylfuran (Component B)]
The component B contains 2,5-bishydroxymethylfuran and / or 3,4-bis from the viewpoint of significantly improving the template strength in a low temperature environment while reducing the content of monomeric furfuryl alcohol. Hydroxymethylfuran is preferred, and 2,5-bishydroxymethylfuran is more preferred.

The content of the component B in the binder composition is 18.0% by mass or more from the viewpoint of significantly improving the mold strength in a low temperature environment while reducing the content of the monomeric furfuryl alcohol. Is preferable, 20.0% by mass or more is more preferable, 21.0% by mass or more is further preferable, 22.0% by mass or more is further preferable, 39.0% by mass or more is further preferable, and 51.0% by mass is 51.0% by mass. The above is even more preferable, and 63.0% by mass or more is even more preferable. The content of the component B in the binder composition is preferably 70.0% by mass or less, more preferably 68.0% by mass or less, and 65.0% by mass or less from the viewpoint of improving storage stability. Is even more preferable, and 63.0% by mass or less is even more preferable. The content of component B can be measured by the method described in Examples.

[Resin (component C)]
The component C can be used without particular limitation as long as it is a resin used as a binder for molding. An acid-curable resin can be exemplified as a resin used as a binder for molding, and examples of the acid-curable resin include furan resin, a condensate of melamine and aldehydes, a condensate of urea and aldehydes, and ethylene urea. One or more selected from the group consisting of condensates of aldehydes can be exemplified. The component C preferably contains a furan resin from the viewpoint of significantly improving the mold strength in a low temperature environment while reducing the content of the monomeric furfuryl alcohol. The component C does not contain furfuryl alcohol.

The furan resin is obtained by polymerizing a monomer composition containing furfuryl alcohol, and can be used without particular limitation as long as it can be used as a binder for molding. The furan resin is a condensate of furfuryl alcohol and urea and a condensate of furfuryl alcohol and melamine from the viewpoint of significantly improving the template strength in a low temperature environment while reducing the content of monomeric furfuryl alcohol. , Condensate of furfuryl alcohol and ethylene urea, condensate of furfuryl alcohol and urea and aldehydes (urea-modified furan resin), condensate of furfuryl alcohol and melamine and aldehydes, furfuryl alcohol and ethylene urea and aldehydes One or more selected from the group consisting of a condensate of flufuryl alcohol, a condensate of flufuryl alcohol and aldehydes, and a condensate of flufuryl alcohol, phenols and aldehydes, and 2 selected from the above group. It is preferable to contain at least one selected from the group consisting of a cocondensate of more than one species, and one selected from the group consisting of a urea-modified furan resin, a furfuryl alcohol condensate and a condensate of furfuryl alcohol and aldehydes. It is more preferable to contain the above, and one or more selected from the group consisting of two or more types of cocondensates selected from the above group.

Examples of the aldehydes include formaldehyde, acetaldehyde, glyoxal, furfural, terephthalaldehyde, hydroxymethylfurfural and the like, and one or more of these can be appropriately used. From the viewpoint of improving the mold strength, it is preferable to use formaldehyde, and from the viewpoint of reducing the amount of formaldehyde generated during molding, it is preferable to use furfural, terephthalaldehyde, or hydroxymethylfurfural.

Examples of the phenols include phenol, cresol, resorcin, bisphenol A, bisphenol C, bisphenol E, bisphenol F and the like, and one or more of these can be used.

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 has 0.6 to 30.0 parts by mass of urea and 0.4 to 50.0 parts of paraformaldehyde with respect to 100.0 parts by mass of furfuryl alcohol. It can be obtained by reacting by mass.

From one or more selected from the group consisting of the urea-modified furan resin, furfuryl alcohol condensate, and a condensate of furfuryl alcohol and aldehydes in the furan resin, and two or more cocondensates selected from the group. The total content of one or more selected from the group is preferably 90% by mass or more from the viewpoint of significantly improving the mold strength in a low temperature environment while reducing the content of monomeric furfuryl alcohol. 95% by mass or more is more preferable, 98% by mass or more is further preferable, substantially 100% by mass is further preferable, and 100% by mass is further preferable. In addition, in this specification, "substantially" means that the amount of an impurity may be contained.

The content of the furan resin in the component C is preferably 80% by mass or more, preferably 90% by mass, from the viewpoint of significantly improving the mold strength in a low temperature environment while reducing the content of the monomeric furfuryl alcohol. The above is more preferable, 95% by mass or more is further preferable, 98% by mass or more is further preferable, substantially 100% by mass is further preferable, and 100% by mass is further preferable.

The nitrogen content in the component C (in the present specification, the nitrogen content means the content of nitrogen atoms) improves the cross-linking density of the resin and significantly improves the template strength in a low temperature environment. From the viewpoint, it is 2.7% by mass or more, preferably 2.8% by mass or more, more preferably 3.7% by mass or more, and further preferably 4.6% by mass or more. The nitrogen content in the component C is 22.0% by mass or less, and 21.0% by mass or less, from the viewpoint of maintaining good kneading property with the fire-resistant aggregate and suppressing a decrease in mold strength. It is preferable, 17.0% by mass or less is more preferable, and 13.9% by mass or less is further preferable. The nitrogen content in component C can be measured by the method described in Examples.

The content of the component C in the binder composition is preferably 5.0% by mass or more from the viewpoint of improving the crosslink density of the resin and significantly improving the mold strength in a low temperature environment. 0% by mass or more is more preferable, and 7.0% by mass or more is further preferable. The content of the component C in the binder composition is preferably 45.0% by mass or less, preferably 45.0% by mass or less, from the viewpoint of maintaining good kneading property with the refractory aggregate and suppressing a decrease in mold strength. It is more preferably 0.0% by mass or less, and further preferably 42.0% by mass or less.

The nitrogen content in the binder composition is preferably 0.1% by mass or more, preferably 0.2% by mass, from the viewpoint of improving the crosslink density of the resin and significantly improving the mold strength in a low temperature environment. The above is more preferable. The nitrogen content in the binder composition is preferably 3.5% by mass or less, preferably 3.2% by mass, from the viewpoint of maintaining good kneading property with the refractory aggregate and suppressing a decrease in mold strength. % Or less is more preferable, and 3.0% by mass or less is further preferable. The nitrogen content in the binder composition can be measured by the method described in Examples.

The content of the component B with respect to the total content of the component B and the component C in the binder composition is a viewpoint of improving the crosslink density of the resin and significantly improving the mold strength in a low temperature environment. Therefore, it is 39.0% by mass or more, preferably 51.0% by mass or more, and more preferably 63.0% by mass or more. The content of the component B with respect to the total content of the component B and the component C in the binder composition is 95.0% by mass or less, 92.0% by mass, from the viewpoint of improving storage stability. It is preferably 90.0% by mass or less, more preferably 90.0% by mass or less, and further preferably 78.0% by mass or less.

The binder composition reduces the content of monomeric furfuryl alcohol when the content of the component B in the binder composition is y and the nitrogen content of the component C is x. However, the above formula (1) is satisfied from the viewpoint of significantly improving the mold strength in a low temperature environment.

The binder composition preferably contains the component B in the binder composition from the viewpoint of significantly improving the template strength in a low temperature environment while reducing the content of the monomeric furfuryl alcohol. The content of the component B is 39.0 to 95.0% by mass, and the nitrogen content in the component C is 2.7 to 22.0% by mass with respect to the total content of the component C. , The above formula (1) is satisfied.

The binder composition preferably contains the component B in the binder composition from the viewpoint of significantly improving the template strength in a low temperature environment while reducing the content of the monomeric furfuryl alcohol. The content of the component B is 51.0 to 95.0% by mass, and the nitrogen content in the component C is 2.7 to 22.0% by mass with respect to the total content of the component C. , The above formula (1) is satisfied.

The binder composition is more preferably the component B in the binder composition from the viewpoint of significantly improving the template strength in a low temperature environment while reducing the content of the monomeric furfuryl alcohol. The content of the component B is 63.0 to 95.0% by mass, and the nitrogen content in the component C is 2.7 to 22.0% by mass with respect to the total content of the component C. Moreover, the above formula (1) is satisfied.

The binder composition is more preferably the component B in the binder composition from the viewpoint of significantly improving the template strength in a low temperature environment while reducing the content of the monomeric furfuryl alcohol. The content of the component B is 63.0 to 95.0% by mass, and the nitrogen content in the component C is 3.7 to 17.0% by mass with respect to the total content of the component C. Moreover, the above formula (1) is satisfied.

The binder composition is more preferably the component in the binder composition from the viewpoint of significantly improving the template strength in a low temperature environment while reducing the content of the monomeric furfuryl alcohol. The content of the component B is 63.0 to 95.0% by mass with respect to the total content of B and the component C, and the nitrogen content in the component C is 4.6 to 13.9% by mass. And, the following formula (2) is satisfied.
1.32x + 57.4 ≤ y (2)

From the viewpoint of improving storage stability, the binder composition preferably has the content of the component B relative to the total content of the component B and the component C in the binder composition 63. The nitrogen content in the component C is 4.6 to 13.9% by mass, and the formula (2) is satisfied.

[Water (component D)]
The content of the component D in the binder composition is 25.0% by mass or less, preferably 20.0% by mass or less, from the viewpoint of improving the mold strength. The content of the component D in the binder composition is preferably 5.0% by mass or more, more preferably 8.0% by mass or more, from the viewpoint of adjusting the viscosity of the binder composition. 0% by mass or more is more preferable. The content of component D can be measured by the method described in Examples.

[Hardening accelerator]
The binder composition may contain a curing accelerator from the viewpoint of improving the mold strength. As the curing accelerator, one or more selected from the group consisting of phenol derivatives, aromatic dialdehydes, and tannins is preferable from the viewpoint of improving the template strength.

Examples of the phenol derivative include resorcin, cresol, hydroquinone, phloroglucinol, methylenebisphenol and the like. The content of the phenol derivative in the binder composition is preferably 1 to 25% by mass, more preferably 2 to 15% by mass, and 3 to 10% from the viewpoint of improving the template strength. It is more preferably by mass%.

Examples of the aromatic dialdehyde include terephthalaldehyde, phthalaldehyde, isophthalaldehyde and the like, and derivatives thereof and the like. The derivatives thereof mean a compound having a substituent such as an alkyl group in the aromatic ring of an aromatic compound having two formyl groups as a basic skeleton. The content of the aromatic dialdehyde in the binder composition is preferably 0.1 from the viewpoint of sufficiently dissolving the aromatic dialdehyde in the furan resin and suppressing the odor of the aromatic dialdehyde itself. It is ~ 15% by mass, more preferably 0.5 to 10% by mass, still more preferably 1 to 5% by mass.

Examples of the tannins include condensed tannins and hydrolyzable tannins. Examples of these condensed tannins and hydrolyzable tannins include tannins having a pyrogallol skeleton and a resorcin skeleton. In addition, bark extracts containing these tannins and extracts from natural products such as plant-derived leaves, fruits, seeds, and gall parasitized by plants may be added. The content of tannins in the binder composition is preferably 0.2 to 10% by mass, more preferably 1.0 to 7% by mass, from the viewpoint of improving the curing rate and the mold strength. %, More preferably 1.9 to 5% by mass.

The viscosity of the binder composition at 25 ° C. is preferably 70 mPa · s or less, and more preferably 50 mPa · s or less, from the viewpoint of workability during the production of the mold composition and the mold production. The viscosity of the binder composition at 25 ° C. can be measured by the method described in Examples.

The binder composition may further contain an additive such as a silane coupling agent. For example, it is preferable that the binder composition contains a silane coupling agent because the final strength of the obtained mold can be further improved. Examples of the silane coupling agent include N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, and N-β- (aminoethyl)-. Aminosilanes such as γ-aminopropyltriethoxysilane and 3-aminopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, Epoxysilanes such as 3-glycidoxypropylmethyldiethoxysilane and 3-glycidoxypropyltriethoxysilane, ureidosilanes, mercaptosilanes, sulfidesilanes, methacryoxysilanes, acryloxysilanes and the like are used. Preferred are aminosilanes, epoxysilanes and ureidosilanes. More preferably, aminosilane and epoxysilane. Among the aminosilanes, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane is preferable. Among the epoxy silanes, 3-glycidoxypropylmethyldimethoxysilane is preferable.

The content of the silane coupling agent in the binder composition is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, from the viewpoint of improving the mold strength. From the same viewpoint, the content of the silane coupling agent in the binder composition is preferably 5% by mass or less, more preferably 3% by mass or less, further preferably 1% by mass or less, and 0.5% by mass. The following is more preferable.

The binder composition for mold molding of the present embodiment is suitably used for molding a self-hardening mold. Here, the self-hardening mold is a mold in which when the binder composition and the curing agent are mixed with sand, the polymerization reaction proceeds with the passage of time and the mold is cured. The temperature of the sand used at that time is in the range of −20 ° C. to 50 ° C., preferably 0 ° C. to 40 ° C. For sand at such a temperature, the mold can be appropriately cured by selecting an appropriate amount of a curing agent and adding it to the sand.

<Composition for molding>
The mold-molding composition of the present embodiment contains the binder composition and a curing agent composition containing a curing agent that cures the mold-molding binder composition. The molding composition of the present embodiment has the same effect as the binder composition.

[Curing agent composition]
The curing agent composition can be used without particular limitation as long as it contains a curing agent that cures the binder composition. Examples of the curing agent include acid-based curing agents, which include sulfonic acid-based compounds such as xylene sulfonic acid (particularly m-xylene sulfonic acid), toluene sulfonic acid (particularly p-toluene sulfonic acid), and methane sulfonic acid, and phosphorus. One or more conventionally known substances such as an acid, a phosphoric acid compound such as an acidic phosphoric acid ester, and sulfuric acid can be used. These compounds are preferably aqueous solutions from the viewpoint of handleability. Further, the curing agent composition may contain one or more solvents selected from the group consisting of alcohols, ether alcohols and esters, and carboxylic acids.

The content of the solvent in the curing agent composition is appropriately adjusted in order to obtain a desired reaction rate and mold strength depending on the temperature of the working environment and the temperature of the fire-resistant particles, but in general, it is generally used. From the viewpoint of dissolving the curing agent composition, 5% by mass or more is preferable, 10% by mass or more is more preferable, and 20% by mass or more is further preferable. The content of the solvent in the curing agent composition is preferably 90% by mass or less, more preferably 80% by mass or less, still more preferably 70% by mass or less, from the viewpoint of improving the mold strength.

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, still more preferably 30% by mass or more, from the viewpoint of improving the mold strength. 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, still more preferably 80% by mass or less, from the viewpoint of dissolving the curing agent composition.

The mass ratio of the binder composition to the curing agent is 10 to 60 parts by mass of the curing agent with respect to 100 parts by mass of the binder composition from the viewpoint of improving the curing rate and improving the mold strength. Is preferable, 10 to 40 parts by mass is more preferable, and 10 to 30 parts by mass is further preferable.

[Mold composition]
The mold composition of the present embodiment contains refractory particles, the binder composition, and the curing agent composition. The mold composition of the present embodiment has the same effect as the binder composition of the present embodiment.

[Refractory particles]
As the refractory particles, one or more conventionally known ones such as silica sand, chromate sand, zircon sand, olivine sand, alumina sand, mullite sand, and synthetic mullite sand can be used, and used fire resistance. Collected particles and regenerated particles can also be used. Among these, it is preferable to contain silica sand.

In the mold composition, the mass ratio of the fire-resistant particles, the binder composition, and the curing agent can be appropriately set, but from the viewpoint of improving the curing rate and the mold strength, the fire-resistant particles It is preferable that the binder composition is in the range of 0.5 to 1.5 parts by mass and the curing agent is in the range of 0.07 to 1 part by mass with respect to 100 parts by mass.

<Molding method>
The method for producing a mold of the present embodiment is a mixing step of mixing the fire-resistant particles, the binder composition, and the curing agent composition to obtain a mold composition, and the mold composition. It comprises a curing step of packing in a mold and curing the mold composition. The method for producing the mold has the same effect as that of the binder composition.

In the mixing step, the order in which the binder composition, the curing agent composition, and the refractory particles are added and mixed is not particularly limited, and the binder composition and the curing agent composition are mixed. After producing the molding composition, the molding composition and the refractory particles may be mixed, and the binder composition, the curing agent composition, and the refractory particles are added and mixed, respectively. However, from the viewpoint of storage stability and mold productivity, it is preferable to mix the binder composition, the curing agent composition, and the refractory particles to obtain a mold composition. Further, from the viewpoint of improving the mold strength, it is preferable to add the curing agent composition to the refractory particles and mix them, and then add and mix the binder composition. When two or more kinds of curing agent compositions are used, each curing agent composition may be mixed and then added, or each curing agent composition may be added separately.

As a method of mixing each raw material in the mixing step, a known general method can be used, for example, a method of adding each raw material by a batch mixer and kneading, or a method of supplying each raw material to a continuous mixer and kneading. There is a way to do it.

In the mold manufacturing method of the present embodiment, the mold can be manufactured by using the conventional mold manufacturing process as it is except for the mixing step.

With respect to the embodiments described above, the present invention further discloses the following compositions, production methods, or uses.
<1> Contains furfuryl alcohol (component A), bishydroxymethylfuran (component B), resin (component C) and water (component D).
A binder composition for molding that satisfies the following conditions (1) to (5).
Condition (1): The content of the component A in the mold-molding binder composition is 30.0% by mass or less Condition (2): The content of the component D in the mold-molding binder composition Condition (3): The content of the component B is 39.0% by mass or more with respect to the total content of the component B and the component C in the binder composition for molding. 95.0% by mass or less Condition (4): Nitrogen content in the component C is 2.7% by mass or more and 22.0% by mass or less Condition (5): The component in the mold-molding binder composition When the content of B is y and the nitrogen content of the component C is x, the following formula (1) is satisfied. 2.97x + 15.2 ≦ y (1)
<2> Contains furfuryl alcohol (component A), bishydroxymethylfuran (component B), resin (component C) and water (component D).
The binder composition for molding according to <1>, which satisfies the following conditions (1) to (5).
Condition (1): The content of the component A in the mold-molding binder composition is 5.0% by mass or more and 30.0% by mass or less Condition (2): In the mold-molding binder composition. Condition (3): The content of the component D is 5.0% by mass or more and 25.0% by mass or less. Condition (4): Content of component B is 39.0% by mass or more and 95.0% by mass or less (4): Condition (5): The content of nitrogen in the component C is 2.7% by mass or more and 22.0% by mass or less. When the content of the component B in the binder composition for molding is y and the nitrogen content of the component C is x, the following formula (1) is satisfied. 2.97x + 15.2 ≦ y (1)
<3> The binder composition for molding according to <1> or <2>, wherein the content of the component A is 10.0% by mass or more and 30.0% by mass or less.
<4> The binder composition for molding according to any one of <1> to <3>, wherein the content of the component A is 15.0% by mass or more and 30.0% by mass or less.
<5> The binder composition for molding according to any one of <1> to <4>, wherein the content of the component D is 8.0% by mass or more and 25.0% by mass or less.
<6> The binder composition for molding according to any one of <1> to <5>, wherein the content of the component D is 10.0% by mass or more and 20.0% by mass or less.
<7> The binder composition for molding according to any one of <1> to <6>, which satisfies the following conditions (3) to (5).
Condition (3): The condition that the content of the component B is 51.0% by mass or more and 95.0% by mass or less with respect to the total content of the component B and the component C in the binder composition for molding ( 4): Nitrogen content in the component C is 2.7% by mass or more and 22.0% by mass or less Condition (5): The content of the component B in the binder composition for molding is y, the above. When the nitrogen content of the component C is x, the following formula (1) is satisfied. 2.97x + 15.2≤y (1)
<8> The binder composition for molding according to any one of <1> to <7>, which satisfies the following conditions (3) to (5).
Condition (3): The condition that the content of the component B is 63.0% by mass or more and 95.0% by mass or less with respect to the total content of the component B and the component C in the binder composition for molding ( 4): Nitrogen content in the component C is 2.7% by mass or more and 22.0% by mass or less Condition (5): The content of the component B in the binder composition for molding is y, the above. When the nitrogen content of the component C is x, the following formula (1) is satisfied. 2.97x + 15.2≤y (1)
<9> The mold molding according to any one of <1> to <8>, wherein the component C contains a furan resin and the content of the furan resin in the component C is 80% by mass or more. Cinder composition for.
<10> The mold molding according to any one of <1> to <9>, wherein the component C contains a furan resin and the content of the furan resin in the component C is 90% by mass or more. Cinder composition for.
<11> The mold molding according to any one of <1> to <10>, wherein the component C contains a furan resin and the content of the furan resin in the component C is 95% by mass or more. Cinder composition for.
<12> The mold molding according to any one of <1> to <11>, wherein the component C contains a furan resin and the content of the furan resin in the component C is 98% by mass or more. Cinder composition for.
<13> The invention according to any one of <1> to <12>, wherein the component C contains a furan resin, and the content of the furan resin in the component C is substantially 100% by mass. A binder composition for molding.
<14> The furan resin is one or more selected from the group consisting of a urea-modified furan resin, a furfuryl alcohol condensate, and a condensate of furfuryl alcohol and aldehydes, and two or more cocondensations selected from the group. The binder composition for molding according to any one of <9> to <13>, which contains at least one selected from the group consisting of substances.
<15> One or more selected from the group consisting of the urea-modified furan resin, furfuryl alcohol condensate, and furfuryl alcohol and aldehydes condensate in the furan resin, and two or more selected from the group. The binder composition for molding according to <14>, wherein the total content of one or more selected from the group consisting of condensates is 90% by mass or more.
<16> One or more selected from the group consisting of the urea-modified furan resin, furfuryl alcohol condensate, and furfuryl alcohol and aldehydes condensate in the furan resin, and two or more selected from the group. The binder composition for molding according to <14> or <15>, wherein the total content of one or more selected from the group consisting of condensates is 95% by mass or more.
<17> One or more selected from the group consisting of the urea-modified furan resin, furfuryl alcohol condensate, and a condensate of furfuryl alcohol and aldehydes in the furan resin, and two or more selected from the group. The binder composition for molding according to any one of <14> to <16>, wherein the total content of one or more selected from the group consisting of condensates is 98% by mass or more.
<18> One or more selected from the group consisting of the urea-modified furan resin, furfuryl alcohol condensate, and a condensate of furfuryl alcohol and aldehydes in the furan resin, and two or more selected from the group. The binder composition for molding according to any one of <14> to <17>, wherein the total content of one or more selected from the group consisting of condensates is substantially 100% by mass.
<19> The curing agent composition for molding according to any one of <1> to <18>, and a curing agent composition containing a curing agent for curing the mold forming binder composition. A composition for molding, which comprises.
<20> Curing containing refractory particles, the mold-molding binder composition according to any one of <1> to <18>, and a curing agent for curing the mold-molding binder composition. A composition for a mold containing an agent composition.
<21> In <20>, the binder composition is 0.5 to 1.5 parts by mass and the curing agent is 0.07 to 1 part by mass with respect to 100 parts by mass of the refractory particles. The described mold composition.
<22> Curing containing fire-resistant particles, the mold-molding binder composition according to any one of <1> to <18>, and a curing agent for curing the mold-molding binder composition. A method for producing a mold, which comprises a mixing step of mixing the agent composition and the mold composition to obtain a mold composition, and a curing step of packing the mold composition in a mold and curing the mold composition.

Hereinafter, examples and the like that specifically show the present invention will be described.

<Measurement method of physical properties>
[Water content]
Measurement was performed based on the Karl Fischer method shown in JIS K 0068 using an automatic moisture measuring device (AQV-2200A manufactured by Hiranuma Sangyo Co., Ltd.).

[Contents of furfuryl alcohol and bishydroxymethylfuran]
The measurement was carried out by gas chromatography analysis under the following conditions using gas chromatography (manufactured by Shimadzu Corporation, GC-2014S).
-Calibration curve: Prepared using furfuryl alcohol and bishydroxymethylfuran.
-Internal standard solution: 1,6-hexanediol-Column: PEG-20M Chromosorb WAW DMCS 60/80 mesh (manufactured by GL Sciences)
-Column temperature: 80 to 200 ° C (8 ° C / min)
・ Injection temperature: 210 ℃
-Detector temperature: 250 ° C. Carrier gas: 50 mL / min (He)

[Nitrogen content]
The measurement was performed based on the Kjeldahl method shown in JIS K 6451-2.

〔viscosity〕
Using an E-type viscometer (RE-80R, manufactured by Toki Sangyo Co., Ltd.), the viscosity was measured at a rotation speed of 100 rpm using a standard rotor (cone angle 1 ° 34'cone radius: 24 mm) at 25 ° C. ..

<Resin manufacturing method>
[Urea-modified furan resin]
609 g of furfuryl alcohol, 0.7 g of 25 mass% sodium hydroxide aqueous solution, 188 g of 92 mass% paraformaldehyde, and 140 g of urea were put into a three-necked flask and reacted at 100 ° C. under normal pressure for 45 minutes. Then, 1.4 g of glutaric acid was added, and the mixture was further reacted at 100 ° C. for 45 minutes. Then, 52 g of urea was added, and the reaction was carried out at 70 ° C. for 30 minutes. After the reaction, the pH was adjusted to 10 with a 25 mass% sodium hydroxide aqueous solution. The obtained composition was distilled under reduced pressure using a rotary evaporator at 110 ° C. and an internal pressure of 5 mmHg to remove water and some furfuryl alcohol. The composition of the obtained reaction product was 71.9% by mass of a urea-modified furan resin and 28.1% by mass of furfuryl alcohol. The nitrogen content of the obtained reaction product was 14.5% by mass, and the nitrogen content of the urea-modified furan resin was 20.2% by mass.

[Furfuryl alcohol condensate]
492 g of furfuryl alcohol and 8 g of glutaric acid were put into a three-necked flask and reacted at 100 ° C. under normal pressure for 5 hours. Then, the pH was adjusted to 10 with a 25 mass% sodium hydroxide aqueous solution. The obtained composition was distilled under reduced pressure using a rotary evaporator at 110 ° C. and an internal pressure of 5 mmHg to remove water and some furfuryl alcohol. The composition of the obtained reaction product was 79.0% by mass of the furfuryl alcohol condensate and 21.0% by mass of the furfuryl alcohol.

[2,5-Bishydroxymethylfuran (BHMF)]
615 g of furfuryl alcohol, 205 g of 92 mass% paraformaldehyde, and 41 g of glutaric acid were put into a three-necked flask and reacted at 100 ° C. under normal pressure for 3 hours. Then, the pH was adjusted to 10 with a 48% aqueous sodium hydroxide solution. The obtained composition was distilled under reduced pressure at 110 ° C. and an internal pressure of 5 mmHg using a rotary evaporator to remove furfuryl alcohol and water. The obtained residue was completely dissolved in chloroform warmed to 40 ° C. and then cooled at 5 ° C. to obtain BHMF crystals. After that, the same operation was repeated twice. The purity of the obtained crystals was 100% by mass.

<Production example of binder composition>
[Manufacturing Example 1]
The resin a was obtained by the procedure described in paragraph 0055 of Japanese Patent Application Laid-Open No. 2013-151019 <Production of Condensate 1>. The unreacted furfuryl alcohol and water content of the resin a were measured, and based on the measurement results, the content of furfuryl alcohol was 50% by mass using the resin a, furfuryl alcohol, water, and a silane coupling agent. %, The content of water was 10% by mass, and the content of the silane coupling agent was 0.15% by mass, and the binder composition according to Production Example 1 was obtained.

[Manufacturing Example 2]
Using the resin a, furfuryl alcohol, water, and a silane coupling agent, the content of furfuryl alcohol is 50% by mass, the content of water is 20% by mass, and the content of the silane coupling agent is 0.15. The content was adjusted to be% by mass, and the binder composition according to Production Example 2 was obtained.

[Manufacturing Example 3]
587 g of furfuryl alcohol, 1.0 g of a 25 mass% sodium hydroxide aqueous solution, 159 g of 92 mass% paraformaldehyde, and 29 g of glutaric acid were put into a three-necked flask and reacted at 125 ° C. under normal pressure for 3 hours. After that, the mixture was cooled to 90 ° C., charged with 35 g of urea, then heated to 105 ° C. and reacted at the same temperature for 2 hours. After the reaction, the mixture was cooled to 75 ° C., 7 g of urea was added, and the mixture was reacted at the same temperature for 20 minutes to obtain a resin b. The furfuryl alcohol in the resin b was 20.0% by mass, the BHMF was 29.5% by mass, the water was 6.8% by mass, and the nitrogen content was 2.4% by mass. 1.5 g of a silane coupling agent, 36 g of furfuryl alcohol, and 145 g of water were added to the resin b and mixed to obtain a binder composition according to Production Example 3. The content of furfuryl alcohol in the binder composition according to Production Example 3 is 20.0% by mass, the content of BHMF is 24.1% by mass, the content of furan resin is 32.9% by mass, and the content of water is contained. The amount was 20.0% by mass, and the nitrogen content in the furan resin was 6.0% by mass.

[Manufacturing Example 4]
588 g of furfuryl alcohol, 1.0 g of a 25 mass% sodium hydroxide aqueous solution, 159 g of 92 mass% paraformaldehyde, and 29 g of benzoic acid were put into a three-necked flask and reacted at 125 ° C. under normal pressure for 2 hours. After that, the mixture was cooled to 90 ° C., 10 g of 92 mass% paraformaldehyde and 50 g of urea were added, the temperature was raised to 105 ° C., and the reaction was carried out at the same temperature for 2 hours. After the reaction, the mixture was cooled to 75 ° C., 11 g of urea was added, and the mixture was reacted at the same temperature for 20 minutes to obtain a resin c. The furfuryl alcohol in the resin c was 22.0% by mass, the BHMF was 26.4% by mass, the water was 7.4% by mass, and the nitrogen content was 3.3% by mass. 1.5 g of a silane coupling agent, 13 g of furfuryl alcohol, and 138 g of water were added to the resin c and mixed to obtain a binder composition according to Production Example 4. The content of furfuryl alcohol in the binder composition according to Production Example 4 is 20.0% by mass, the content of BHMF is 22.4% by mass, the content of furan resin is 34.6% by mass, and the content of water is contained. The amount was 20.0% by mass, and the nitrogen content in the furan resin was 8.1% by mass.

[Manufacturing Example 5]
359 g of the resin c, 121 g of furfuryl alcohol, 173 g of water, 345 g of BHMF, and 1.5 g of a silane coupling agent were added to a three-necked flask and stirred at 40 ° C. for 30 minutes to obtain a binder composition according to Production Example 5. .. The content of furfuryl alcohol in the binder composition according to Production Example 5 is 20.0% by mass, the content of BHMF is 44.0% by mass, the content of furan resin is 14.7% by mass, and the content of water is contained. The amount was 20.0% by mass, and the nitrogen content in the furan resin was 8.1% by mass.

[Manufacturing Example 6]
569 g of flufuryl alcohol, 0.9 g of 25 mass% sodium hydroxide aqueous solution, 154 g of 92 mass% paraformaldehyde, and 28 g of glutaric acid were put into a three-necked flask and reacted at 125 ° C. under normal pressure for 3 hours. After that, the mixture was cooled to 90 ° C., charged with 58 g of ethylene urea, heated to 105 ° C., and reacted at the same temperature for 3 hours. After the reaction, the mixture was cooled to 75 ° C., 8 g of urea was added, and the mixture was reacted at the same temperature for 20 minutes to obtain a resin d. The furfuryl alcohol in the resin d was 20.6% by mass, the BHMF was 28.0% by mass, the water was 6.5% by mass, and the nitrogen content was 2.8% by mass. 1.5 g of a silane coupling agent, 31 g of furfuryl alcohol, and 147 g of water were added to the resin d and mixed to obtain a binder composition according to Production Example 6. The content of furfuryl alcohol in the binder composition according to Production Example 6 is 20.0% by mass, the content of BHMF is 23.0% by mass, the content of furan resin is 34.1% by mass, and the content of water is contained. The amount was 20.0% by mass, and the nitrogen content in the furan resin was 6.7% by mass.

[Manufacturing Example 7]
587 g of furfuryl alcohol, 1.0 g of a 25 mass% sodium hydroxide aqueous solution, 195 g of 92 mass% paraformaldehyde, and 29 g of glutaric acid were placed in a three-necked flask and reacted at 125 ° C. under normal pressure for 2 hours. After that, the mixture was cooled to 90 ° C., charged with 28 g of melamine, heated to 105 ° C., and reacted at the same temperature for 2 hours. After the reaction, the mixture was cooled to 75 ° C., 8 g of urea was added, and the mixture was reacted at the same temperature for 20 minutes to obtain a resin e. The furfuryl alcohol in the resin e was 19.3% by mass, the BHMF was 27.5% by mass, the water was 7.3% by mass, and the nitrogen content was 2.8% by mass. 1.5 g of a silane coupling agent, 43 g of furfuryl alcohol, and 141 g of water were added to the resin e and mixed to obtain a binder composition according to Production Example 7. The content of furfuryl alcohol in the binder composition according to Production Example 7 is 20.0% by mass, the content of BHMF is 22.4% by mass, the content of furan resin is 34.6% by mass, and the content of water is contained. The amount was 20.0% by mass, and the nitrogen content in the furan resin was 6.6% by mass.

[Manufacturing Example 8]
The binder composition according to Production Example 6 was produced by the following procedure based on the production method of KH-Y described in Special Table 2014-501175. 197 g of furfuryl alcohol, 196 g of 92 mass% paraformaldehyde, and 4.7 g of benzoic acid were put into a three-necked flask, and the mixture was reacted at 110 ° C. under normal pressure for 1 hour. Further, 394 g of furfuryl alcohol and 9.4 g of benzoic acid were added to this reaction product, the temperature was raised to 135 ° C., and the mixture was refluxed for 5 hours. The temperature after completion of the reaction was 125 ° C. Then, 60 g of urea was added and cooled to 60 ° C. over about 40 minutes to obtain a resin f. The furfuryl alcohol in the resin f was 23.2% by mass, the BHMF was 14.8% by mass, the water was 7.3% by mass, and the nitrogen content was 3.3% by mass. 1.5 g of a silane coupling agent and 137 g of water were added to the resin f and mixed to obtain a binder composition according to Production Example 8. The content of furfuryl alcohol in the binder composition according to Production Example 8 is 20.0% by mass, the content of BHMF is 12.7% by mass, the content of furan resin is 45.7% by mass, and the content of water is contained. The amount was 20.0% by mass, and the nitrogen content in the furan resin was 6.1% by mass.

<Examples 1 to 21 and Comparative Examples 1 to 9>
[Manufacturing of binder composition for mold molding]
Using the urea-modified furan resin, furfuryl alcohol / formaldehyde resin, BHMF, furfuryl alcohol, water and silane coupling agent obtained in the above production example, mixing was performed at 40 ° C. for 30 minutes, and Example 1 To 16, the binder composition for mold molding of Comparative Examples 1 to 8 was obtained. As the molding binder compositions of Examples 17 to 21, Comparative Examples 9 and Reference Examples 1 and 2, the compositions of Production Examples 1 to 8 shown above were used, respectively.

[Manufacturing of mold composition]
Under the conditions of 5 ° C. and 55% RH, the curing agent composition was added to 100 parts by mass of the furan regenerated silica sand, and then 0.8 parts by mass of the binder composition for molding shown in Table 1 was added. , These were mixed to obtain a mold composition. As the curing agent composition, a xylene sulfonic acid / sulfuric acid-based curing agent (Kaoritener US-3, Kaoritener C-21: Kao Quaker Co., Ltd.) was used. The amount of the curing agent composition added is 0.32 parts by mass with respect to 100 parts by mass of the regenerated silica sand of furan, and the compressive strength of the test piece described later is 0.20 to 0.35 MPa / 30 minutes. The ratio of US-3 and Kaoritener C-21 was adjusted. When the addition amount was 0.32 parts by mass and did not meet the above compressive strength, only Kao Lightener US-3 was used, and the addition amount was increased so as to satisfy the above compressive strength.

[Evaluation of mold compressive strength]
Immediately after kneading, the mold composition is filled in a cylindrical test piece frame having a diameter of 50 mm and a height of 50 mm, and after 30 minutes, the die is removed and the compressive strength (MPa) is determined by the method described in JIS Z 2604-1976. Was measured, and this strength was defined as "compressive strength after 30 minutes". It was confirmed that the amount of the curing agent was appropriate, using "compressive strength after 30 minutes" as a guideline for the curing rate. Separately, the mold composition is similarly filled in the test piece frame, and the die is punched after 2 hours, and 24 hours after the filling, the compressive strength (MPa) is determined by the method described in JIS Z 2604-1976. Was measured and used as "compressive strength after 24 hours". The higher the value, the higher the mold strength. The evaluation results are shown in Tables 1 and 2.

Claims (5)

The furfuryl alcohol (component A), bishydroxymethylfuran (component B), resin (component C) and water (component D) are contained, the component C contains a furan resin, and the furan resin in the component C is contained. A binder composition for molding, wherein the content of the binder is 80% by mass or more.
A mold-molding binder composition in which the mold-molding binder composition satisfies the following conditions (1) to (5).
Condition (1): The content of the component A in the mold-molding binder composition is 30.0% by mass or less Condition (2): The content of the component D in the mold-molding binder composition Condition (3): The content of the component B is 39.0% by mass or more with respect to the total content of the component B and the component C in the binder composition for molding. 95.0% by mass or less Condition (4): Nitrogen content in the component C is 2.7% by mass or more and 22.0% by mass or less Condition (5): The component in the mold-molding binder composition When the content of B is y and the nitrogen content of the component C is x, the following formula (1) is satisfied. 2.97x + 15.2 ≦ y (1) The furan resin is a urea-modified furan resin, a condensate of furfuryl alcohol and urea, a condensate of furfuryl alcohol and melamine, a condensate of furfuryl alcohol and ethylene urea, a condensate of furfuryl alcohol and melamine and aldehydes, And one or more selected from the group consisting of condensates of furfuryl alcohol, ethylene urea and aldehydes, and one or more selected from the group consisting of two or more cocondensates selected from the above group. Item 2. The binder composition for molding according to Item 1 . A composition for molding, which comprises the binder composition for molding according to claim 1 or 2 , and a curing agent composition containing a curing agent for curing the binder composition for molding. A mold containing refractory particles, the binder composition for molding according to claim 1 or 2 , and a curing agent composition containing a curing agent for curing the binder composition for molding. Composition for. The fire-resistant particles, the binder composition for molding according to claim 1 or 2 , and the curing agent composition containing a curing agent for curing the binder composition for molding are mixed and molded. A method for producing a mold, which comprises a mixing step of obtaining a composition for use and a curing step of packing the composition for a mold into a mold and curing the composition for a mold.