JP2014084423A - Thermosetting furan resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermosetting furan resin composition which becomes a cured product that prevents dimensional change and has a high strength after having been cured.SOLUTION: A thermosetting furan resin composition contains: a furan-based resin (A); a curing catalyst (B); an additive (C) which is one or more compound selected from a group consisting of sodium chloride, lithium chloride, sodium bromide and lithium bromide; and a filler (D) in which the pH of a dispersion liquid obtained when the filler has been dispersed in water is 9 or less.

Description

  The present invention relates to a thermosetting furan resin composition, and more particularly to a thermosetting furan resin composition that becomes a cured product having high strength when cured.

  Resins composed of co-condensates of furfuryl alcohol and formaldehyde (so-called furan resins) are excellent in heat resistance, solvent resistance, chemical resistance, etc. It is used as a matrix resin in various industrial fields.

  For example, in Patent Document 1, a furan resin composition is prepared by mixing a furan resin with a curing catalyst such as an organic acid such as toluenesulfonic acid or xylenesulfonic acid, and the desired furanic resin composition is thermally cured. The cured product is obtained.

  However, the conventional furan resin composition has a problem in that the moisture generated by the condensation reaction at the time of synthesis and the moisture generated by the curing reaction are dissipated at the time of curing. .

  As an attempt to solve the above problem, for example, Patent Document 2 discloses a technique for producing a furan resin composition after once removing the water generated by the condensation reaction after the synthesis of the furan resin is completed. ing. According to the technique disclosed in Patent Document 2, the amount of moisture diffused at the time of curing decreases, so that the dimensional change at the time of curing can be reduced.

Japanese Patent Laid-Open No. 06-322103 Japanese National Patent Publication No. 08-506374

  However, in the method disclosed in Patent Document 2, the effect of reducing the dimensional change is not yet sufficient, and further improvement has been demanded. Further, it has been required to further increase the strength of the cured product when the thermosetting furan resin composition is cured.

  This invention is made | formed in view of the said present condition, The objective is to provide the thermosetting furan resin composition used as the hardened | cured material which is hard to change a dimension and is high intensity | strength when it hardens | cures. is there.

  The inventors of the present invention have made extensive studies on the additive for reducing the dimensional change, and by adding an additive such as lithium chloride to the furan resin composition, the furan resin composition in the curing reaction It has become clear that the diffusion of moisture is suppressed, thereby reducing the dimensional change.

  In addition, the present inventors sought a filler that can improve the strength of the cured product while being cured while maintaining the effect of reducing the dimensional change due to the above additives, and when the filler was dispersed in water. The present invention shown below was completed by obtaining the knowledge that the liquidity of the resin is related to the improvement of the strength of the cured product and examining the types of suitable fillers based on the knowledge.

The thermosetting furan resin composition of the present invention is one or more selected from the group consisting of a furan resin (A), a curing catalyst (B), sodium chloride, lithium chloride, sodium bromide, and lithium bromide. And an additive (C), which is a compound of the above, and a filler (D) having a pH of 9 or less when the filler is dispersed in water.
The filler preferably contains a kaolin type mineral, and the kaolin type mineral preferably contains kaolinite.
The kaolin-type mineral is preferably a surface-treated surface treatment agent, and the surface treatment agent is more preferably an aminosilane-based surface treatment agent.
The filler preferably has a median diameter of 1.4 μm to 4.8 μm.
The present invention is also a cured product obtained by curing the thermosetting furan resin composition.
Furthermore, this invention is also a furan resin laminated body containing the said furan resin hardened | cured material and a reinforced fiber.

  The thermosetting furan resin composition of the present invention exhibits an excellent effect of being hard to change in size when cured and having high strength of the cured product.

It is the image which observed the cross section of the hardened | cured material which hardened the thermosetting furan resin composition of Example 2 2000 times using the electron microscope. It is the image which observed the cross section of the hardened | cured material which hardened the thermosetting furan resin composition of the comparative example 1 2000 times using the electron microscope.

<Thermosetting furan resin composition>
The thermosetting furan resin composition of the present invention is one or more selected from the group consisting of a furan resin (A), a curing catalyst (B), sodium chloride, lithium chloride, sodium bromide, and lithium bromide. And an additive (C), which is a compound of the above, and a filler (D) whose pH of the dispersion when the filler is dispersed in water is 9 or less. The components (A) to (D) will be described below.

<Furan resin (A)>
In the present invention, the furan resin (A) is preferably a furan resin or a modified furan resin. Furan resin is a polymer starting from furfural or furfuryl alcohol. Such polymers are furfuryl alcohol type, furfuryl alcohol / furfural cocondensation type, furfuryl alcohol / aldehyde cocondensation type, furfural / ketone cocondensation type, furfural / phenol cocondensation type, furfuryl alcohol / urea cocondensation type. And furfuryl alcohol / phenol co-condensation type. From the viewpoint of being able to supply industrially stably, it is preferably a furfuryl alcohol type or a furfuryl alcohol / formaldehyde co-condensation type.

  Examples of the modified furan resin include epoxy modification, phenol modification, aldehyde modification, urea modification, and melamine modification.

  The moisture content of the furan resin (A) is not particularly limited, but is preferably 10% or less, more preferably 9% or less, from the viewpoint of reducing the dimensional change.

<Curing catalyst (B)>
The curing catalyst (B) is not particularly limited as long as it can cure the furan resin (A), and examples thereof include an acid curing catalyst, a thermal reaction type latent acid curing catalyst, and a mixture thereof. Examples of the acid curing catalyst include organic acids such as organic sulfonic acids and organic carboxylic acids, inorganic acids such as hydrochloric acid and sulfuric acid, and aqueous solutions containing one or more of these. When an organic acid aqueous solution or an inorganic acid aqueous solution is used as the curing catalyst (B), the concentration of the aqueous solution is preferably as high as possible, and more preferably in the vicinity of the saturated aqueous solution. This is because the moisture contained in the thermosetting furan resin composition can be reduced.

  Examples of the organic sulfonic acid include p-toluenesulfonic acid, benzenesulfonic acid, xylenesulfonic acid, methanesulfonic acid and the like. Examples of the organic carboxylic acid include malonic acid, succinic acid, maleic acid, oxalic acid, acetic acid, lactic acid, malic acid, tartaric acid, benzoic acid, citric acid and the like.

  The heat-reactive latent acid curing catalyst is preferably one that hardly reacts with the components contained in the furan-based resin (A) at room temperature and reacts rapidly by heating during curing to generate an acid. From the viewpoint of stability at normal temperature and a high reaction rate at the time of heating, the curing catalyst (B) contains either an inorganic ammonium salt, a primary amine salt, a secondary amine salt, or a tertiary amine salt. More preferably, it contains ammonium chloride, ammonium sulfate, ammonium nitrate, methylamine hydrochloride, dimethylamine hydrochloride, ethylamine hydrochloride, or diethylamine hydrochloride. By including a heat-reactive latent acid curing catalyst as the curing catalyst (B), both shortening of the curing time and extension of the pot life can be achieved.

  The addition amount of the curing catalyst (B) is not particularly limited, but from the viewpoint of curing the furan resin (A) uniformly and ensuring the pot life, 0.5% with respect to 100 parts by weight of the furan resin (A). -10 parts by weight is preferable, and 1-8 parts by weight is more preferable.

<Additive (C)>
The additive (C) is one or more compounds selected from sodium chloride, lithium chloride, sodium bromide, and lithium bromide, and the types and ratios thereof are the types of the furan resin (A) and the curing catalyst (B). And is selected according to the water content. Considering that the dimensional change can be reduced and that the solubility in the furan-based resin (A) is high at room temperature, the additive (C) preferably contains lithium chloride, and may consist only of lithium chloride. More preferred.

  The addition amount of the additive (C) is not particularly limited, but from the viewpoint of reducing the dimensional change and ensuring a viscosity that is easy to handle when mixed with the furan resin (A), the furan resin (A) 100. 0.2-10 weight part is preferable with respect to a weight part, 0.5-5 weight part is more preferable, More preferably, it is 1-3 weight part.

<Filler (D)>
The thermosetting furan resin composition of the present invention is characterized by containing a filler (D) having a pH of 9 or less when dispersed in water. The filler (D) exhibiting such liquidity is uniformly dispersed in the furan resin (A), can significantly improve the strength after curing, and can reduce the dimensional change of the additive (C). Combined with the effect, the reduction in dimensional change is extremely excellent.

  Here, “the pH of the dispersion when dispersed in water is 9 or less” means that the pH of the dispersion when dispersing 0.5 g of filler in 100 g of water is 9 or less. means. In the filler (D), the pH of the dispersion when 0.5 g of the filler is dispersed in 100 g of water is preferably 3 or more and 8 or less, more preferably 4 or more and 7 or less.

  The filler (D) showing the liquidity of the above dispersion can be used without particular limitation as long as the pH of the dispersion is 9 or less, and can be used as a rock-forming mineral, pegmatite mineral, contact mineral, skarn mineral. , Ore minerals, wax stone minerals, clay minerals, kaolin type minerals and the like. Of these, kaolin-type minerals are preferably included. Since kaolin-type minerals exhibit high water absorption, kaolin-type minerals absorb moisture in the furan-based resin (A) and make it difficult for moisture to be released to the outside. Can do. Moreover, since kaolin-type mineral itself has high hardness, the intensity | strength of the hardened | cured material can be raised by including a kaolin-type mineral.

  In consideration of dispersibility in the furan resin (A), the filler (D) preferably has a median diameter of 1.4 μm or more and 4.8 μm or less, more preferably 1.4 μm or more and 2.0 μm. The median diameter is as follows. As the median diameter of the filler (D), a volume-based 50% diameter (D50) value when the filler is analyzed by a laser diffraction method is adopted.

Kaolinite, nacrite, dickite, halloysite, antigolite, monoclinic chrysotile stone, orthorhombic chrysotile stone, parachrysolite stone, lizard stone, amesite, kellyite, velcherin, greenerite, nuporeite It is preferable that kaolinite is included. Here, the form of kaolinite may be any form such as hydrous kaolin, calcined kaolin, dry kaolin, etc., and its chemical composition is represented by Al ₂ Si ₂ O ₅ (OH) ₄ . Since such kaolinite is highly compatible with the furan resin (A), it is uniformly dispersed (A) in the furan resin and no voids are formed at the interface with the furan resin (A). The change can be reduced.

  The addition amount of the filler (D) varies depending on the viscosity of the furan resin (A). However, if the amount is too small, the effect of improving the strength characteristics cannot be obtained. Therefore, the amount is preferably 10 to 200 parts by weight, more preferably 15 to 100 parts by weight, and still more preferably 20 to 80 parts by weight with respect to 100 parts by weight of the furan resin (A).

  The kaolin-type mineral is preferably a surface-treated surface treatment agent. By being surface-treated with the surface treatment agent, compatibility with the furan resin is improved and chemical bonding with the furan resin (A) is possible, so adhesion at the interface with the furan resin (A). The power can be further improved.

  The surface treatment agent is not particularly limited as long as it can react or bond with the furan resin (A), but is preferably an organosilane surface treatment agent. Examples of the organic silane surface treatment agent include amino silane surface treatment agents, epoxy silane surface treatment agents, vinyl silane surface treatment agents, acrylic silane surface treatment agents, mercapto silane surface treatment agents, alkyl silane surface treatment agents, Examples include halogenosilane-based surface treatment agents and azolesilane-based surface treatment agents. Among these, from the viewpoint of reactivity with the furan resin (A), it is preferable to use an aminosilane-based surface treatment agent, an epoxysilane-based surface treatment agent, or an acrylsilane-based surface treatment agent, and more preferably an aminosilane-based surface treatment agent. A surface treatment agent is used.

<Other additives>
In order to improve the strength characteristics of the cured product when the thermosetting furan resin composition is cured, an inorganic filler may be added in addition to the filler (D). The inorganic filler is not particularly limited as long as the elastic modulus is high and high filling is possible, but an inorganic filler is preferable from the viewpoint of preventing curing inhibition, and specifically, glass powder, silica, talc, mica. Aluminum hydroxide is preferable, and silica or aluminum hydroxide is more preferable in view of cost.

  The addition amount of the inorganic filler varies depending on the viscosity of the furan resin (A), but from the viewpoint of improvement in strength characteristics and impregnation into the base material due to thickening, relative to 100 parts by weight of the furan resin (A). The amount is preferably 200 parts by weight or less, more preferably 150 parts by weight or less, and still more preferably 100 parts by weight or less.

  From the viewpoint of adjusting the viscosity and reactivity of the thermosetting furan resin composition, a reactive diluent may be added to the furan resin (A). The reactive diluent is not particularly limited as long as it has low viscosity, is compatible with the furan resin component, and can be cured together with the curing of the thermosetting furan resin composition, but has high compatibility with the furan resin. From this viewpoint, it is preferable to add water, furfuryl alcohol, furfural, or a mixture thereof, and water is more preferable.

  The addition amount of the reactive diluent is preferably 100 parts by weight or less, more preferably 90 parts by weight or less, and still more preferably from 100 parts by weight of the furan resin from the viewpoint of impregnation into the base material. 80 parts by weight or less, preferably 0.1 parts by weight or more, and more preferably 0.5 parts by weight or more. Further, from the viewpoint of preventing sagging during molding, the amount is preferably 1 part by weight or more, and more preferably 5 parts by weight or more.

<Thermosetting furan resin composition>
The thermosetting furan resin composition of the present invention has a viscosity at 25 ° C. of 50 to 10,000 mPa · s, 100 to 5000 mPa · s, and 200 to 5000 mPa · s in consideration of the ease of handling. In particular, it is preferably 2900 mPa · s or more, more preferably 3000 mPa · s or more, and further preferably 3100 mPa · s or more. Further, from the viewpoint of impregnation into the base material, the viscosity at 25 ° C. is 4000 mPa · s or less, more preferably 3700 mPa · s or less, and further preferably 3500 mPa · s or less.

<Method for producing thermosetting furan resin composition>
The method for producing the thermosetting furan resin composition of the present invention comprises one or more additives selected from the group consisting of sodium chloride, lithium chloride, sodium bromide, and lithium bromide (A). C), a step of adding the filler (D) to the furan resin (A), and a step of adding the curing catalyst (B) to the furan resin (A). The order of these steps is not particularly limited, but it is preferable to add the curing catalyst (B) last.

  In the step of adding the additive (C), the additive (C) may be added as a powder, or may be added as a solution or a dispersion. From the viewpoint of facilitating dispersion in the furan resin (A), the additive (C) is preferably added as a solution. Examples of the solvent include water, methanol, ethanol, a mixed solution thereof, and the like. Among these, water is preferably used as a solvent from the viewpoint of uniformly adding sodium chloride, lithium chloride, sodium bromide, and lithium bromide.

  The concentration of the additive (C) in the solution or dispersion is not particularly limited because it is adjusted by the type of the additive (C), the solvent, the addition temperature, the target dimensional accuracy, and the like. When added as an aqueous solution, if the concentration of the aqueous solution is low, the amount of moisture increases and the dimensional change increases. The concentration of the aqueous solution is such that the amount of water added to the composition as an aqueous solution is 10 parts by weight or less (for example, 0.5 to 10 parts by weight) with respect to 100 parts by weight of the furan resin (A). preferable. The concentration of the aqueous solution can be, for example, 10 to 25% by weight in the case of sodium chloride and 30 to 45% by weight in the case of lithium chloride.

  In the step of adding the filler (D), the filler (D) is added to the furan resin (A) and mixed by stirring.

  In the step of adding the curing catalyst (B), the curing catalyst (B) is added to the furan resin (A) and mixed by stirring or the like.

<Hardened furan resin>
The furan resin cured product of the present invention can be obtained by heat curing the thermosetting furan resin composition. Although the curing conditions are not particularly limited, it is generally preferable to cure at 70 to 130 ° C., for example, for 5 to 20 hours. The cured furan resin of the present invention has a flexural modulus measured in accordance with JIS K7171 of 1800 MPa or more, more preferably 2000 MPa or more, and further preferably 2500 MPa or more. The bending strength of the cured product is preferably 24.5 MPa or more, more preferably 26 MPa or more. Further, after curing for 100 hours in a constant temperature bath at 25 ° C. and a humidity of 50%, the dimensional retention rate is 99% or more and the weight retention rate is 97.5% or more.

<Flanc resin laminate>
The furan resin laminate of the present invention contains the cured furan resin and reinforcing fibers. The furan resin laminate of the present invention can be produced by impregnating the above-mentioned thermosetting furan resin composition into reinforcing fibers and heat-curing. The impregnation method is not particularly limited, and examples thereof include a method of impregnating a reinforcing fiber with a thermosetting furan resin composition with an impregnation roll. The impregnation amount of the thermosetting furan resin composition is not particularly limited.

  Examples of the reinforcing fiber include a nonwoven fabric, a chopped strand mat, and a roving cloth.

  As the material of the nonwoven fabric, for example, a high-strength and high-elasticity material such as polyester, high-density polyethylene (HDPE), polypropylene, etc. Among them, a resin is preferable, and a continuous filament or staple fiber that is flexible and porous is used. Felts, mats, spunbonds, webs and the like provided can also be used.

  As a chopped strand mat, for example, strands such as glass fibers are cut into a certain length and dispersed in a mat shape, and then a thermoadhesive agent such as a thermoplastic resin is uniformly applied and thermally melted. Those which are bonded to form a mat are preferred.

  As the roving cloth, glass fiber, carbon fiber, aramid fiber, inorganic fiber, organic fiber, whisker and the like are preferable. Among them, glass fiber is preferable from the balance of strength and price of the furan resin laminate to be obtained. The reinforcing fiber preferably has a fiber diameter in the range of 3 to 25 μm, and more preferably has a fiber diameter of 5 to 20 μm from the viewpoint of strength and price.

<Method for producing furan resin laminate>
In the method for producing a furan resin laminate according to the present invention, a fibrous base material is impregnated and cured with the thermosetting furan resin composition. As the fibrous base material, those similar to those exemplified as the reinforcing fiber can be used.

  The curing method of the thermosetting furan resin composition impregnated in the fibrous base material is not particularly limited. For example, the fibrous base material impregnated with the thermosetting furan resin composition is placed in a mold, A method in which hot air is blown into the mold or the mold itself is heated to cure, and a fibrous base material impregnated with the thermosetting furan resin composition is directly blown with hot air or sandwiched between hot plates to be cured by heating. Methods and the like. Although the temperature at the time of heat-hardening the thermosetting furan resin composition of the said invention is not specifically limited, Generally 70-130 degreeC is preferable, for example.

  In the manufacturing method of the furan resin laminated body of this invention, a laminated body with small dimensional shrinkage after hardening can be simply given by using the above thermosetting furan resin compositions with a small dimensional change. Therefore, according to the present invention, a furan resin laminate having good quality can be produced at a low cost, and can be particularly suitably used for applications such as FRP.

  Hereinafter, the thermosetting furan resin composition of the present invention will be described based on examples. In addition, this invention is not limited only to these Examples.

Example 1
As furan resin (A), a co-condensate of furfuryl alcohol and formaldehyde (viscosity 2700 mPa · s, water content 7.4% by weight) was prepared. 5 parts by weight of lithium chloride as an additive (C) was added to 100 parts by weight of this furan resin, and the mixture was stirred at 1000 rpm for 5 minutes using a homodisper. After stirring, to the 100 parts by weight of the furan resin, the filler shown in the column “Filler” in Example 1 in Table 1 is added in the amount shown in the “Parts” column in the table, and the homogen is added. After stirring for 5 minutes at 1000 rpm using a disper, add 4.0 parts by weight of a paratoluenesulfonic acid 50% aqueous solution as the curing catalyst (B) in the amount shown in the column of “curing catalyst” in Table 1, and use a homodisper. The thermosetting furan resin composition of Example 1 was obtained by stirring for 5 minutes at 1000 rpm.

(Example 2 and Comparative Examples 1 to 3)
Example 2 and Comparative Example 1 were the same as Example 1 except that the amount of the curing catalyst (B) and the type and number of parts of the filler differed from Example 1 as shown in Table 1 below. The thermosetting furan resin composition of ~ 3 was obtained. In Example 2, a filler obtained by surface-treating calcined kaolin with an aminosilane surface treatment agent was used.

* 1 Firing kaolin Satinton W (Made by Hayashi Kasei)
* 2 Surface-treated calcined kaolin Translink 445 (manufactured by Hayashi Kasei Co., Ltd.)
* 3 Aluminum hydroxide particles Heidilite H32 (Showa Denko)
* 4 Aluminum hydroxide particles BW103STA (manufactured by Nippon Light Metal Co., Ltd.)
* 5 Fly ash finalash (manufactured by Yoden Business)
“PH” in Table 1 is a value obtained by measuring a dispersion obtained by dispersing 0.5 g of the filler (D) in 100 g of water with a pH meter (product name: handy type pH meter, manufactured by HORIBA Co., Ltd.). is there.
“Median diameter” in Table 1 is the volume-based 50% diameter (D50) when the filler is analyzed by laser diffraction using a laser diffraction particle size distribution analyzer (SALD-7000, manufactured by Shimadzu Corporation). Value.

(Evaluation of thermosetting furan resin composition)
The thermosetting furan resin composition (5500 g / m ² ) obtained in each example and each comparative example was uniformly impregnated into a polyester nonwoven fabric substrate (thickness 5 mm, basis weight 1000 g / m ² ) with an impregnation roll. Then, the furan resin laminated body was obtained by leaving still in the metal mold | die of an internal dimension 240mmx240mmx5mm, and making it harden | cure at 90 degreeC for 200 hours. The bending elastic modulus, bending strength, dimensional retention rate, and weight retention rate were evaluated for each furan resin laminate. The evaluation results are shown in Table 2 below. “Viscosity” in Table 2 means the viscosity of the thermosetting furan resin composition of each Example and each Comparative Example.

In Table 2, “flexural modulus” and “bending strength” are values obtained by measuring the molded furan resin laminate in accordance with JIS K7171 “Plastics—Determination of bending characteristics”.
In Table 2, “Dimension retention” is based on the following formula after measuring the dimension of the molded furan resin laminate after cutting into 100 mm × 100 mm, curing in a constant temperature room (humidity 50%) at 25 ° C. for 100 hours. This is the calculated value.
Dimension retention (%) = dimension after 100 hours (mm) / dimension after cutting (mm) × 100
In Table 2, “weight retention” is based on the following formula after measuring the weight of the molded furan resin laminate after cutting into 100 mm × 100 mm and curing in a constant temperature room (humidity 50%) at 25 ° C. for 100 hours. This is the calculated value.
Weight retention (%) = weight after 100 hours (g) / weight after cutting (g) × 100

  1 is an observation image when a cross section of a cured product obtained by curing the thermosetting furan resin composition of Example 2 is observed with a laser microscope, and FIG. 2 is a thermosetting furan resin composition of Comparative Example 1. It is the image which observed the cross section of the hardened | cured material which hardened | cured the thing with the laser microscope. The gray part of the observation image shown in FIG.1 and FIG.2 is a filler (kaolinite or aluminum hydroxide), and the surrounding black part is furan resin.

  As shown in FIG. 1, the filler (kaolinite) having a pH of 9 or less in the dispersion is uniformly and densely dispersed in the furan resin, whereas as shown in FIG. In addition, in the filler (aluminum hydroxide) whose pH of the dispersion exceeds 9, voids are formed at the interface between the furan resin and the filler. This is considered to be a cause of lowering the flexural modulus of the cured product after the voids are cured. In FIG. 1, the furan resin and the filler are in close contact with each other without forming the void.

(Discussion)
The hardened | cured material produced with the thermosetting furan resin composition of Examples 1-2 was a value whose bending elastic modulus and bending strength are remarkably high with respect to that of Comparative Examples 1-3. In addition, since any of Examples 1-2 and Comparative Examples 1-3 contained lithium chloride as an additive, little dimensional change was seen. From these results, by adding an additive (C) made of lithium chloride and a filler (D) having a pH of 9 or less when dispersed in water to the thermosetting furan resin composition. Thus, it became clear that a thermosetting furan resin composition having a small dimensional change and a cured product having a high strength was obtained, and the effects of the present invention were shown.

  The thermosetting furan resin composition of the present invention is effectively used for a matrix resin of a laminate such as FRP.

Claims (8)

  A furan resin (A), a curing catalyst (B), an additive (C) that is one or more compounds selected from the group consisting of sodium chloride, lithium chloride, sodium bromide, and lithium bromide, and filling A thermosetting furan resin composition comprising: a filler (D) having a dispersion having a pH of 9 or less when the material is dispersed in water.   The thermosetting furan resin composition according to claim 1, wherein the filler contains a kaolin-type mineral.   The thermosetting furan resin composition according to claim 2, wherein the kaolin-type mineral contains kaolinite.   The thermosetting furan resin composition according to claim 2, wherein the kaolin-type mineral has a surface-treated surface treatment agent.   The thermosetting furan resin composition according to claim 4, wherein the surface treatment agent is an aminosilane-based surface treatment agent.   The thermosetting furan resin composition according to any one of claims 1 to 5, wherein the filler has a median diameter of 1.4 µm to 4.8 µm.   The furan resin hardened | cured material obtained by thermosetting the thermosetting furan resin composition as described in any one of Claims 1-6.   A furan resin laminate comprising the furan resin cured product according to claim 7 and reinforcing fibers.