Fiber molding, fibrous binder, and applications thereof

Abstract

One problem to be addressed by the present invention is to provide a fiber molding having sufficient strength, and a composite material using the same. Another problem to be addressed by the present invention is to provide, with the use of carbon fibers, a fiber molding having sufficient strength, and a composite material using the same.　A fibrillated fibrous binder is used to fabricate a fiber molding processed into a nonwoven fabric or the like. One embodiment of the fiber molding comprises a main fiber material and a fibrous binder. The content ratio of the main fiber material and the fibrous binder is 1-20 parts by weight of the fibrous binder with respect to 100 parts by weight of the main fiber material. The fibrous binder has a crill ratio of 1.25 to 3.00.

Description

Fiber moldings, fibrous binders, and their applications

[0001] The present invention relates to a fibrous molded article, a fibrous binder used therein, and applications thereof.

[0002] Fiber reinforced plastics (FRP) are reinforced plastic materials that have a matrix of epoxy resin, phenolic resin, or the like, to which fiber materials such as glass fiber or carbon fiber are compounded to improve various functions. Carbon fiber, in particular, is a lightweight material that has excellent strength and elastic modulus, and carbon fiber reinforced plastics (CFRP) using carbon fiber are used in an extremely wide range of fields, such as automobile components, ship components, aircraft components, spacecraft components, drone components, civil engineering and construction materials, sporting goods, and components for electronic devices and electrical appliances such as personal computers.

[0003] Generally, FRP is produced by impregnating a sheet of fiber material with a resin component that serves as the matrix. While a wide range of technological developments have been made to improve the performance of FRP, one of the important factors in producing composite materials using such fiber materials is that the fiber molding itself must have sufficient strength before being impregnated with the matrix.

[0004] A typical example of a sheet-like fiber material used in FRP is nonwoven fabric. Various methods for producing nonwoven fabric from fiber materials have already been developed, not limited to the field of FRP. Furthermore, research and development has been conducted on the production of nonwoven fabrics intended for use in FRP.

[0005] For example, in a fiber-reinforced plastic molding that uses a thermoplastic resin as a binder for carbon fibers, if the thermoplastic resin melts at high temperatures such as during thermal melting, the fixation of the intertwining points between the carbon fibers is impaired, resulting in the collapse of the three-dimensional structure of the carbon fibers, making the carbon fibers more likely to be oriented in a specific direction, and reducing strength. To solve this problem, a method has been disclosed in which a papermaking sheet before resin impregnation is subjected to a papermaking process using a mixed dispersion of carbon fibers and water-swollen filtrated fibers (for example, Patent Document 1).

[0006] Furthermore, when inorganic fibers such as carbon fibers, glass fibers, and metal fibers are processed into nonwoven fabrics by a wet papermaking method, the inorganic fibers are hydrophobic and therefore have poor dispersibility in water, making it difficult to obtain an inorganic fiber sheet with good formation.To solve this problem, a technique using a dispersant containing a specific surfactant or resin has been disclosed (for example, Patent Document 2).

[0007] In recent years, there has been a global consensus calling for the promotion of sustainable development, and as the use of composite materials composed of fibers such as carbon fiber and a matrix material increases as described above, there is also a demand for the development of methods for their reuse.

[0008] International Publication No. 2014 / 021366 Japanese Patent Application Laid-Open No. 2017-57511

[0009] As mentioned above, one way to utilize the excellent properties of the fibers incorporated into FRP is to ensure that the strength of the fiber molding itself is excellent before it is impregnated with the matrix. However, when fiber components such as carbon fibers are separated from molded products such as CFRP for reuse, the recycled carbon fibers obtained by separation are significantly different from virgin fibers and often end up being fragmented and short fibers compared to virgin fibers. Even when attempts are made to reprocess recycled carbon fibers into fiber molding sheets, it has been difficult to process them into sheets in the first place, or even if they can be processed into sheets, it has been difficult to obtain the strength, durability, and other performance required for FRP materials.

[0010] Therefore, one approach to producing fiber molding sheets using recycled fibers is to increase the amount of binder. However, from the perspective of producing FRP with desired performance, it has been desired to minimize the amount of binder in order to make the most of the properties of the main fiber material. Furthermore, there has been a need for a binder suitable for producing moldings using various types of fiber materials, not just carbon fiber.

[0011] In view of the above circumstances, one of the problems to be solved is to provide a fiber molding having sufficient strength and a composite material using the same. Another problem to be solved is to provide a fiber molding having sufficient strength using recycled carbon fiber and a composite material using the same. Another problem to be solved is to provide a fiber molding having sufficient strength using various types of fiber materials and a composite material using the same.

[0012] As a result of extensive research, the present inventors have found that by using a fibrillated fibrous binder, a fiber molding having a predetermined strength suitable for the production of FRP, etc. The present disclosure is based on this finding.

[0013] The invention presented in this disclosure can be understood in multiple aspects and may include, for example, the following embodied aspects as means for solving problems. Note that in this disclosure, the invention presented in this disclosure is also simply referred to as "the present invention" either as a comprehensive concept or according to each individual aspect.

[0014] [1] A fiber molding comprising a main fiber material and a fibrous binder, wherein the content ratio of the main fiber material to the fibrous binder is 1 to 20 parts by weight per 100 parts by weight of the main fiber material, and the acrylic ratio of the fibrous binder is 1.25 to 3.00. [2] The fiber molding according to [1] above, wherein the average fiber length of the fibrous binder is 0.30 to 2.50 mm. [3] The fiber molding according to [1] or [2] above, wherein the main fiber material is one or more fibers selected from the group consisting of carbon fiber, glass fiber, metal fiber, natural fiber, cellulose-based fiber, recycled fiber, semi-synthetic fiber, and synthetic fiber. [4] The fiber molding according to [1] or [2] above, wherein the main fiber material is one or more fibers selected from the group consisting of carbon fiber, glass fiber, PET-based fiber, and aramid-based fiber. [5] The fiber molded product according to [1] or [2] above, wherein the main fiber material is carbon fiber. [6] The fiber molded product according to any one of [3] to [5] above, wherein the carbon fiber is virgin carbon fiber, recycled carbon fiber, or a mixture thereof. [7] The fiber molded product according to any one of [1] to [6] above, wherein the fibrous binder is fibrillated cellulose fiber. [8] The fiber molded product according to any one of [1] to [7] above, wherein the fineness ratio of the fibrous binder is 95% or less. [9] A fiber-reinforced resin molded product comprising the fiber molded product according to any one of [1] to [8] above and a resin component impregnated into the fiber molded product.

[10] A fibrous binder for a fiber molded product, wherein the fibrillated cellulose fiber has a Cryl ratio of 1.25 to 3.00, and the fineness ratio of the fibrillated cellulose fiber is 95% or less.

[0015] According to one or more aspects of the invention disclosed herein, a fiber molded article having sufficient strength can be provided. Furthermore, according to one or more aspects of the invention disclosed herein, a fiber molded article having sufficient strength can be provided using recycled carbon fiber. Furthermore, according to one or more aspects of the invention disclosed herein, a fiber molded article having sufficient strength can be provided using various types of fiber materials. Furthermore, according to one or more aspects of the invention disclosed herein, a variety of excellent composite materials can be provided using the above-described fiber molded article.

[0016] This disclosure has been filed as an international application under the Patent Cooperation Treaty, and the original language of the application is Japanese. It is intended that this disclosure will be translated into the languages ​​required by each designated and elected state upon entry into those states. In this disclosure, unless otherwise specified, Japanese nouns may be singular or plural, depending on the context or the full text of this disclosure. Furthermore, when translated into a language such as English that distinguishes between countable and uncountable nouns, and between singular and plural countable nouns, unless otherwise specified, the singular designation includes the plural, and the plural designation includes the singular, depending on the context or the full text of this disclosure.

[0017] Hereinafter, embodiments of the present invention will be described. In this disclosure, the term "one embodiment" with respect to the present invention refers to any one embodiment for describing the present invention in detail, unless otherwise specified, and does not deny or limit the existence of other or multiple embodiments. As will be described below, the present invention may include multiple embodiments within its scope. Furthermore, multiple embodiments may also be provided as modified forms, for example, by various combinations of the components (or technical features) shown in this disclosure. Furthermore, in this disclosure, when simply referring to an "embodiment," it includes one or multiple embodiments unless otherwise specified.

[0018] In this disclosure, unless otherwise specified, the expression "AA to BB" in relation to a numerical range means "AA or more and BB or less" (where "AA" and "BB" represent arbitrary numerical values). Furthermore, unless otherwise specified, the units of the lower and upper limits are the same as the units immediately following the latter (i.e., "BB" here). Furthermore, in this disclosure, the combination of the lower and upper limits of a numerical range can be arbitrarily selected from the group of lower or upper limit values ​​exemplified as preferred numerical values, etc. Furthermore, the expression "X and / or Y" means both X and Y, or either one of them.

[0019] 1. Fibrous Binder The fibrous binder of the present disclosure can be suitably used as a binder for binding together the main fiber material that constitutes the body of a fibrous molded article, which will be described in detail below.

[0020] A preferred example of the fibrous binder is fibrillated cellulose fiber. In this disclosure, "fibrillation" refers to the process of causing fibers to fluff or splinter by friction or beating. In other words, it can also be said that small fibers (i.e., fibrils) are fluffed from the fiber body by friction or beating. In this disclosure, "fibrillated cellulose fiber" refers to cellulose fiber that has been fibrillated and has small fibers (fibrils) fluffed on the surface.

[0021] Examples of cellulose fibers include natural cellulose fibers, chemically modified cellulose fibers, and regenerated cellulose fibers. Examples of natural cellulose fibers include wood pulp such as softwood pulp and hardwood pulp, and herbaceous pulp such as straw pulp, bamboo pulp, linter pulp, hemp pulp, and kenaf pulp. Examples of chemically modified cellulose fibers include oxidized, etherified, cationized, or esterified cellulose fibers. Examples of regenerated cellulose fibers include rayon, cupra, and lyocell.

[0022] That is, fibrillated cellulose can be obtained by subjecting cellulose fibers to treatment such as friction or beating using, for example, a single disc refiner (SDR), a double disc refiner (DDR), a beater, a mixer, a mill, a grinding device, etc. to loosen and fluff the surfaces of the fibers. Alternatively, a suspension or slurry of cellulose fibers may be prepared and then treated at high speed and high pressure using a homogenizer.

[0023] The fibrous binder preferably satisfies at least one of the following indices relating to properties and the like, or any two or more of these indices.

[0024] <Freeness> In the present disclosure, "freeness" is an index indicating the fibrillation of fibers, and is determined by measuring the amount of water removed when a test sample (for example, a fibrous binder in the present disclosure) is made into a slurry and the water is drained all at once through a specified filter. More specifically, the freeness value in the present disclosure can be determined by the measurement method used in the following examples, etc. The higher the freeness value, the easier the water is removed and the less fuzzing there is. Conversely, the lower the value, the more difficult the water is removed and the more fuzzing there is. Note that freeness is also referred to as beating degree or freeness.

[0025] The freeness of the fibrous binder, as measured according to the specific test methods implemented in the examples, etc., detailed below, may preferably be 0 to 100 ml. A freeness within this range contributes to the formation of a fibrous molded article with sufficient strength. From the viewpoint of further pursuing the strength of the fibrous molded article, the lower limit of the freeness of the fibrous binder is theoretically most preferably 0, and practically may be 5 ml or more. On the other hand, the upper limit of the freeness of the fibrous binder may more preferably be 50 ml or less, and even more preferably 40, 30, or 20 ml or less.

[0026] <Average Fiber Length of Fibrous Binder> The average fiber length of the fibrous binder may preferably be 0.30 to 2.50 mm. Having the average fiber length within this range contributes to the formation of a fibrous molded product with sufficient strength. In order to further enhance the strength of the fibrous molded product, more preferable lower and upper limits may be as follows. The lower limit of the average fiber length of the fibrous binder may more preferably be 0.35 mm or more, and even more preferably be 0.40, 0.45, or 0.50 mm or more. The upper limit of the average fiber length of the fibrous binder may more preferably be 2.00, 1.75, or 1.50 mm or less, and even more preferably be 1.25 mm or less.

[0027] <Average fiber diameter of fibrous binder> The average fiber diameter of the fibrous binder may preferably be 10.0 to 40.0 μm. Having an average fiber diameter within this range contributes to the formation of a fibrous molded article with sufficient strength. From the viewpoint of further pursuing the strength of the fibrous molded article, more preferable lower and upper limits are as follows. The lower limit of the average fiber diameter of the fibrous binder may more preferably be 15.0 μm or more, and even more preferably be 20.0 μm or more. The upper limit of the average fiber diameter of the fibrous binder may more preferably be 38.0 μm or less, and even more preferably be 35.0 μm or less.

[0028] <Cryl Ratio of Fibrous Binder> In this disclosure, the "cryl ratio" refers to the ratio of the reduction in the ultraviolet and infrared regions of the transmitted light when light is incident on a fibrous binder slurry. Fibrils, which have been formed by rubbing, beating, or other processes to separate the fiber walls from the fiber (body or trunk) and have a diameter approximately 1 / 100 of the fiber, scatter and absorb primarily ultraviolet light, regardless of whether they remain attached to the fiber or are floating separately. Therefore, the transmitted light in the ultraviolet region is reduced relative to the incident light, and the amount of reduction correlates with the total surface area of ​​the fibrils. On the other hand, non-fibril fibers primarily scatter and absorb infrared light, and therefore the transmitted light in the infrared region is reduced relative to the incident light, and the amount of reduction correlates with the total surface area of ​​the non-fibril fibers. Therefore, the cryl ratio serves as an indicator of the degree of fibrillation of a fibrous binder. The cryl ratio value in this disclosure can be determined by the measurement method used in the following examples, etc.

[0029] The acrylic ratio of the fibrous binder is preferably 1.25 to 3.00. Having the acrylic ratio within this range contributes to the formation of a fibrous molded article with sufficient strength. From the viewpoint of further pursuing the strength of the fibrous molded article, the lower limit of the acrylic ratio is more preferably 1.30 or more, and even more preferably 1.35 or more. The upper limit of the acrylic ratio is more preferably 2.80, 2.60, or 2.40 or less.

[0030] <Fineness Ratio (%) of Fibrous Binder> In the present disclosure, the fineness ratio is an index showing the proportion of fine fibers having a fiber length of less than 0.2 mm. The value of the fineness ratio in the present disclosure can be determined by the measurement method used in the following examples, etc. In the process of fibrillating the fibers, the fibers are excessively ground and finely divided to a fiber length of less than 0.2 mm, and it is considered that these fibers have a low contribution to the binding effect of the fibrous molded article.

[0031] The fineness ratio of the fibrous binder is preferably 10 to 95%. More specifically, it is as follows. The upper limit of the fineness ratio of the fibrous binder is preferably 95% or less. Having the fineness ratio within this range contributes to the formation of a fibrous molded body with sufficient strength. From the viewpoint of further pursuing the strength of the fibrous molded body, the upper limit of the fineness ratio of the fibrous binder is more preferably 90% or less, and even more preferably 85, 80, 75, or 70% or less. The lower limit of the fineness ratio of the fibrous binder may be set arbitrarily from the viewpoint of further pursuing the strength of the fibrous molded body, but is usually preferably 10, 20, 30, or 40% or more.

[0032] 2. Fiber Molded Product The fiber molded product of the present disclosure is a molded product containing a main fiber material and a fibrous binder as constituent materials. The shape of the molded product is not particularly limited, but preferred shapes include a sheet or plate. The fibrous binder described above of the present disclosure can be suitably used as the fibrous binder.

[0033] The main fiber material is the main material of the molded body. The content ratio of the main fiber material to the fiber binder is preferably 1 to 20 parts by weight of the fibrous binder per 100 parts by weight of the main fiber material.

[0034] In general, in FRP, which is obtained by impregnating a nonwoven fabric (fiber molding) as a base material with a resin component that serves as a base material (matrix) and then curing it, there has been a strong demand for the amount of binder component in the nonwoven fabric to be as small as possible. This is presumably because, from the perspective of making the most of the inherent properties of the main fiber material, binders have been considered an unnecessary component. However, it is difficult to produce a fiber molding such as a nonwoven fabric that has a reasonable strength using only the main fiber material without using any binder, and so until now, it has been unavoidable to use as little binder as possible when producing fiber moldings such as nonwoven fabrics.

[0035] In contrast, the fiber molding of the present disclosure uses the above-mentioned specific fibrous binder, which allows the fiber molding to have sufficient strength. Moreover, it has been found that such a fibrous molding has excellent strength and the like even when further processed into a form such as FRP.

[0036] As described above, the amount of fibrous binder per 100 parts by weight of the main fiber material can be any value between 1 and 20 parts by weight. More specifically, the amount of fibrous binder per 100 parts by weight of the main fiber material can be 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 part by weight. Expressed as a numerical range, the upper limit of the amount of fibrous binder per 100 parts by weight of the main fiber material is more preferably 18 parts by weight or less, and even more preferably 15, 13, or 10 parts by weight or less. On the other hand, the lower limit of the amount of fibrous binder per 100 parts by weight of the main fiber material is more preferably 2, 3, or 4 parts by weight or more.

[0037] The main fiber material and the fibrous binder can be mixed by adding the main fiber material and the fibrous binder to a liquid medium such as water and stirring the mixture. When mixing the main fiber material and the fibrous binder, other additives such as a dispersant and a thickener may also be added.

[0038] The use of a dispersant can impart hydrophilic properties to the hydrophobic main fiber material and reduce secondary aggregation by promoting repulsion between fibers. Examples of dispersants include polyoxyalkylene monophenyl ether, polyether-based urethane resin, and polyoxyethylene polyoxypropylene stearyl ether. The amount of dispersant added is preferably 1 to 20 parts by weight, more preferably 3 to 10 parts by weight, per 100 parts by weight of the main fiber material.

[0039] Furthermore, the use of a thickener can impart viscosity to the slurry and reduce secondary aggregation of the hydrophobic main fiber material. Examples of thickeners include polyethylene oxide and sodium polyacrylate. The amount of thickener to be added is preferably 1 to 50 parts by weight, more preferably 5 to 30 parts by weight, per 100 parts by weight of the main fiber material.

[0040] <Main Fiber Material> The main fiber material is not particularly limited as long as it can be formed into woven fabrics, knitted fabrics, nonwoven fabrics, etc. The main fiber material may be inorganic or organic. Examples of inorganic fibers include carbon fiber, glass fiber, and metal fiber. Examples of organic fibers include "natural fibers" such as cotton, hemp, and animal hair, "synthetic fibers" made from petroleum, wood-derived cellulose fibers, and "semi-synthetic fibers" or "regenerated fibers" made from natural materials through various processes. Examples of "synthetic fibers" include polyamide fibers, polyester fibers, polyurethane fibers, polyvinyl alcohol fibers, pitch fibers, polyacrylonitrile (PAN) fibers, phenolic fibers, polyphenylene sulfide fibers, polyvinyl chloride fibers, polypropylene fibers, polyethylene fibers, and polystyrene fibers. Examples of "regenerated fibers" obtained from natural materials include rayon, cupra, and lyocell.

[0041] Preferred examples of the main fiber material include carbon fiber, glass fiber, metal fiber, cellulose-based fiber, recycled fiber, semi-synthetic fiber, and synthetic fiber. More specifically, examples of inorganic fibers include carbon fiber, glass fiber, and metal fiber, while examples of organic fibers include cellulose-based fiber, pitch-based fiber, PAN-based fiber, phenol-based fiber, PET-based fiber, aramid-based fiber, and polyphenylene sulfide-based fiber. Among these, more preferred examples of the main fiber material include carbon fiber, glass fiber, PET-based fiber, and aramid-based fiber, and even more preferred examples of the main fiber material include carbon fiber. Examples of carbon fiber include rayon-based carbon fiber, pitch-based carbon fiber, PAN-based carbon fiber, and phenol-based carbon fiber, and activated carbon fiber may also be used. One type of main fiber material may be used alone, or two or more types may be used.

[0042] The carbon fiber may be a first-time carbon fiber, a recycled carbon fiber (recycled carbon fiber), or a mixture of these. In this disclosure, the term "first-time" (or unused) with respect to carbon fiber is used as the opposite term to the term "recycled" and refers not to a "recycled" (or recycled) fiber, but to a brand-new fiber that is used for the first time after production as fiber, such as a so-called virgin fiber. In this disclosure, "recycled" (or recycled) carbon fiber refers to a fiber recovered through a recycling process using in-process scraps generated during the production process and used CFRP products (products that were once used for some purpose as carbon fiber) that are discarded as waste materials as raw materials for recycling. Furthermore, in this disclosure, with regard to carbon fiber, "recycled carbon fiber" is also referred to as "recycled carbon fiber," "recovered carbon fiber," or, as is commonly called, "regenerated carbon fiber" (in English, it is also commonly called Recycled Carbon Fiber (abbreviation: rCF)).

[0043] <Average fiber length of main fiber material> The average fiber length of the main fiber material may be preferably 1 to 100 mm. Having the average fiber length within this range contributes to the formation of a fibrous molded product with sufficient strength. To further enhance the strength of the fibrous molded product, more preferable lower and upper limits may be as follows. The lower limit of the average fiber length of the main fiber material may more preferably be 2, 3, or 4, and even more preferably 5 mm or more. The upper limit of the average fiber length of the main fiber material may more preferably be 80, 60, 50, 40, or 30 mm or less, and even more preferably 20 mm or less.

[0044] <Average fiber diameter of main fiber material> The average fiber diameter of the main fiber material may preferably be 1.0 to 50.0 μm. Having an average fiber diameter within this range contributes to the formation of a fibrous molded product with sufficient strength. From the viewpoint of further pursuing the strength of the fibrous molded product, more preferable lower and upper limits are as follows. The lower limit of the average fiber diameter of the main fiber material may more preferably be 2.0, 3.0, 4.0, or 5.0 μm or more, and even more preferably be 6.0 μm or more. The upper limit of the average fiber diameter of the fibrous binder may more preferably be 40.0, 30.0, 20.0, or 15.0 μm or less, and even more preferably be 10.0 μm or less.

[0045] In one preferred embodiment of the present disclosure, recycled carbon fiber (rCF), which is carbon fiber separated and recovered from FRP or the like, can be suitably used. Such recycled carbon fiber is typically shorter than the original fiber length before being processed into FRP or the like, and has a rough surface, which tends to result in insufficient strength when processed into nonwoven fabrics. However, by using the fibrous binder of the present disclosure, nonwoven fabrics using such recycled carbon fiber as a fiber material can be made to have sufficient strength. In another preferred embodiment, recycled carbon fiber and virgin carbon fiber (unused carbon fiber) may be mixed to form the main fiber material.

[0046] The method for forming the fiber into a fibrous molded article such as a nonwoven fabric is not particularly limited, and a conventional method can be used. For example, in a method for manufacturing a nonwoven fabric, a fiber sheet can be obtained by a wet method using a main fiber material cut to an appropriate length as a raw material.

[0047] In addition to the fibrous binder and main fiber material described above, the molded article of the present disclosure may also use other binders and other materials. Examples of such materials include painters used in papermaking, such as starch, SBR, polyvinyl alcohol-based aqueous solutions, unsaturated polyester-based aqueous solutions, and acrylic-based aqueous solutions. Furthermore, polyvinyl alcohol-based fibrous binders and composite fibers such as core-sheath fibers, parallel fibers, and radially split fibers may also be used as moist heat-bonding types. Specific examples include combinations of polypropylene (core) and polyethylene (sheath), polypropylene (core) and ethylene vinyl alcohol (sheath), high-melting-point polyester (core) and low-melting-point polyester (sheath), and high-melting-point polyester (core) and polyethylene (sheath). Furthermore, fibers composed solely of polyethylene or polypropylene may also be used as fully fused types. Various fibrillated fibrous binders may also be used. A wide range of binders, both synthetic and natural, can be used. Such fibrillated fibrous binders may include, for example, acrylic fibers, polyethylene fibers, polypropylene fibers, polyacrylonitrile fibers, nylon fibers, aramid fibers, and the like.

[0048] A preferred embodiment of the fiber molded article of the present disclosure may be a sheet-shaped molded article. In the case of a sheet-shaped molded article, the basis weight thereof is preferably 20 to 200 g / m 2 By setting the lower limit of the basis weight to the above-mentioned preferable value or more, it is possible to prevent the sheet-form molded article from having a shortage of tensile strength. From the viewpoint of preventing the sheet-form molded article from having a shortage of tensile strength, the lower limit of the basis weight is more preferably 30 g / m 2 , more preferably 40 g / m 2 On the other hand, by setting the upper limit of the basis weight to the above-mentioned preferred value or less, it is possible to easily remove moisture and dry the sheet in the manufacturing process. From the viewpoint of ease of drying treatment, the upper limit of the basis weight is more preferably 190, 180, or 170 g / m2 , more preferably 160 or 150 g / m 2 It is possible.

[0049] The density of the fiber molding of the present disclosure is preferably 0.05 to 0.20 g / cm 3 By setting the lower limit of the density to the above-mentioned preferred value or more, it is possible to improve the composite balance with the resin when processing into FRP, etc. From the viewpoint of such composite balance with the resin, the lower limit of the density is more preferably 0.06 or 0.07 g / cm 3 or more, more preferably 0.08 or 0.09 g / cm 3 On the other hand, by setting the upper limit of the density to the above-mentioned preferred value or less, impregnation with resin can be more easily carried out when processing into FRP or the like. From the viewpoint of resin impregnation, the upper limit of the density is more preferably 0.19 or 0.18 g / cm 3 , more preferably 0.17 or 0.16 g / cm 3 It is possible.

[0050] The fiber molded article of the present disclosure can be adjusted to have a good tensile strength. The tensile strength of the fiber molded article of the present disclosure can be adjusted appropriately according to needs. There are several ways to adjust the tensile strength, and it can be adjusted, for example, by adjusting the amount of fibrous binder. When measured according to the specific test method (using a test piece 15 mm wide and 150 mm long) performed in the examples described in detail below, the tensile strength of the fiber molded article of the present disclosure can be adjusted to, for example, at least 0.06 or 0.07 kN / mm or more. Even higher tensile strengths can be adjusted, for example, to 0.10, 0.15, 0.19, 0.21, or 0.22 kN / mm or more, or even 0.23, 0.25, 0.30, or 0.40 kN / mm or more.

[0051] 3. Applications of Fiber Molded Products (3.1) The fiber molded products of the present disclosure can be used in a wide range of applications. For example, various FRPs can be obtained by impregnating a sheet-shaped fiber molded product of the present disclosure (also referred to as a fiber molded product sheet) with a resin matrix and curing the impregnated product. Examples of FRPs include glass fiber reinforced plastics, carbon fiber reinforced plastics, boron fiber reinforced plastics, and aramid fiber reinforced plastics.

[0052] (3.2) When activated carbon fiber is used as the main material of the fiber molding of the present disclosure, it can be used as an adsorbent for liquid and gas phases. The adsorbent may be suitable for applications such as water purification and chemical filters for semiconductor manufacturing clean rooms.

[0053] The present invention will be described in more detail below with reference to examples, but the technical scope (or technical reach) of the invention presented in this disclosure is not limited to the following examples. Furthermore, the following measurement methods, calculation methods, evaluation methods, and other methods can be used to determine numerical values ​​when the invention presented in this disclosure is specified using numerical values.

[0054] Example FB1 (fibrous binder) (1) Preparation of pulp slurry: 300 g of unbeaten LBKP (bleached hardwood pulp) (manufactured by Nippon Paper Industries Co., Ltd.) was disintegrated to obtain a 3.0% (W / V) slurry. (2) Fibrillation: The obtained pulp slurry was fibrillated by 11 passes through a single-disc refiner, followed by dilution with water to obtain a 0.5% (W / V) slurry with a freeness of 32 ml, an average fiber length of 0.78 mm, an average fiber diameter of 20.8 μm, a cryl ratio of 1.37, and a fineness ratio of 48.4%.

[0055] Example FB2 (fibrous binder) (1) Preparation of pulp slurry: 300 g of unbeaten NBKP (bleached softwood pulp) (manufactured by Nippon Paper Industries Co., Ltd.) was disintegrated to obtain a 3.0% (W / V) slurry. (2) Fibrillation: The obtained pulp slurry was fibrillated by circulating it through a single-disc refiner for four passes, and then diluted with water to obtain a 0.5% (W / V) slurry with a freeness of 15 ml, an average fiber length of 1.03 mm, an average fiber diameter of 28.8 μm, a cryl ratio of 1.63, and a fineness ratio of 49.9%.

[0056] Example FB3 (fibrous binder) (1) Preparation of pulp slurry A 3.0% (W / V) slurry was obtained in the same manner as in Example FB2 (1). (2) Fibrillation The obtained pulp slurry was fibrillated by circulating it through a single-disc refiner for 10 passes, and then diluted with water to obtain a 0.5% (W / V) slurry with a freeness of 0 ml, an average fiber length of 0.56 mm, an average fiber diameter of 25.6 μm, a cryl ratio of 2.14, and a fineness ratio of 59.3%.

[0057] <Comparative Example FB1 (fibrous binder)> (1) Preparation of chemically modified pulp 40 kg of unbeaten NBKP (manufactured by Nippon Paper Industries Co., Ltd.) was added to 4000 L of an aqueous solution containing 312 g of TEMPO (manufactured by Sigma-Aldrich) (0.05 mmol per 1 g of bone-dry cellulose) and 4112 g of sodium bromide (1.0 mmol per 1 g of bone-dry cellulose) and stirred. Then, an aqueous sodium hypochlorite solution was added so that the sodium hypochlorite concentration was 5.5 mmol / g, and the oxidation reaction was initiated at room temperature. To prevent a decrease in pH during the reaction, a 3 M aqueous sodium hydroxide solution was added successively to adjust the pH to 10. The reaction was terminated when the sodium hypochlorite was consumed and the pH in the system no longer changed. Hydrochloric acid was added to the reaction mixture to adjust the pH to 2, and the pulp was thoroughly washed with water by repeatedly dehydrating and diluting with water. The pulp was then dehydrated until the pulp solids concentration reached 20% by weight, yielding a chemically modified pulp with a carboxyl group content of 1.4 mmol / g.

[0058] (2) Fibrillation The resulting chemically modified pulp was dispersed in water, and sodium hydroxide was added and stirred to obtain a 1.1% (W / V) slurry at pH 7.7. 4,300 kg of the resulting slurry was fibrillated by 20 passes through a monoflow double-disc refiner at a circulation rate of 80%. The resulting slurry was then diluted with water to obtain a 0.5% (W / V) slurry with a freeness of 0 ml, an average fiber length of 0.29 mm, an average fiber diameter of 30.3 μm, a cryl ratio of 3.33, and a fineness ratio of 99.8%.

[0059] Comparative Example FB2 (fibrous binder) (1) Preparation of pulp slurry A 3.0% (W / V) slurry was prepared in the same manner as in Example FB1 (1). (2) Dilution The obtained pulp slurry was diluted with water to obtain a 0.5% (W / V) slurry with a freeness of 620 ml, an average fiber length of 0.94 mm, an average fiber diameter of 19.8 μm, a cryl ratio of 0.83, and a fine ratio of 30.7%.

[0060] Comparative Example FB3 (fibrous binder) (1) Preparation of pulp slurry A 3.0% (W / V) slurry was obtained in the same manner as in Example FB1 (1). (2) Fibrillation The obtained pulp slurry was fibrillated by circulating it through a single-disc refiner for five passes, and then diluted with water to obtain a 0.5% (W / V) slurry with a freeness of 78 ml, an average fiber length of 0.83 mm, an average fiber diameter of 20.2 μm, a cryl ratio of 1.22, and a fineness ratio of 42.6%.

[0061] Comparative Example FB4 (fibrous binder) (1) Preparation of pulp slurry A 3.0% (W / V) slurry was prepared in the same manner as in Example FB2 (1). (2) Dilution The obtained pulp slurry was diluted with water to obtain a 0.5% (W / V) slurry with a freeness of 650 ml, an average fiber length of 2.11 mm, an average fiber diameter of 28.0 μm, a cryl ratio of 0.98, and a fine ratio of 13.5%.

[0062] Comparative Example FB5 (fibrous binder) (1) Preparation of pulp slurry A 3.0% (W / V) slurry was obtained in the same manner as in Example FB2 (1). (2) Fibrillation The obtained pulp slurry was fibrillated by two passes through a single-disc refiner, and then diluted with water to obtain a 0.5% (W / V) slurry with a freeness of 362 ml, an average fiber length of 1.80 mm, an average fiber diameter of 27.6 μm, a cryl ratio of 1.20, and a fineness ratio of 25.7%.

[0063] Example S1 (Fiber Molded Product Sheet) Blend (1): Recycled carbon fiber 94% (W / W), fibrous binder 6% (W / W) At room temperature, using a commercial mixer with a power of 2800 W and a capacity of 3.9 L, 0.08 g of a dispersant (aqueous solution of polyether-based polyurethane resin, manufactured by Meisei Chemical Industry Co., Ltd., model number PULSET HA) and 140 g of a viscosity agent (a 0.1% (W / W) aqueous solution of polyethylene oxide, manufactured by Meisei Chemical Industry Co., Ltd., model number ALKOX SK) were added to 700 ml of water and stirred uniformly. After that, 1.33 g of recycled carbon fiber (manufactured by Carbon Fiber Recycle Kogyo Co., Ltd., Toray Industries, Inc. model number T800SC scraps were secondarily heated and passed through a 9 mm sieve, average fiber diameter 7 μm, average fiber length 10 mm, moisture content 1.4%) was added as the main fiber material, and 16.8 g of the fibrous binder of Example FB1 was added, and the mixture was stirred at a rotation speed of 15,000 rpm for 6 minutes to obtain a slurry. This slurry was hand-sheeted using a round (16 mm diameter) hand-sheet machine (manufactured by Tozai Seiki Co., Ltd.), and the sheet was subjected to a primary press (5 minutes) and a secondary press (2 minutes) using an AUTOMATIC SHEET PRESS (manufactured by Kumagaya Riki Kogyo Co., Ltd.) at a standard press pressure of 410±10 kPa in accordance with JIS P8222:2015. The sheet was then dried in a dryer at 50°C for 30 minutes to obtain a fiber sheet of Example S1(1).

[0064] Blend (2): Carbon fiber 94% (w / w), fibrous binder 6% (w / w) A fiber molded body sheet of Example S1(2) was obtained in the same manner as Blend (1), except that 1.33 g of carbon fiber (manufactured by Toray Industries, Inc., model number T700SC-12K-50C, average fiber diameter 7 μm, average fiber length 12 mm, moisture content 1.0%) was used as the main fiber material.

[0065] Blend (3): Glass fiber 94% (w / w), fibrous binder 6% (w / w) A fiber molded sheet of Example S1(3) was obtained in the same manner as Blend (1), except that 1.40 g of glass fiber (manufactured by PFG Fiber Glass Corporation, model number E225, average fiber diameter 7 μm, average fiber length 5 mm, moisture content 6.0%) was used as the main fiber material.

[0066] Blend (4): PET fiber 94% (w / w), fibrous binder 6% (w / w) A fiber molded sheet of Example S1(4) was obtained in the same manner as Blend (1), except that 1.40 g of PET fiber (manufactured by Teijin Limited, model number TA04N SD 0.6x5, average fiber diameter 7 μm, average fiber length 5 mm, moisture content 5.9%) was used as the main fiber material.

[0067] Blend (5): Aramid fiber 94% (w / w), fibrous binder 6% (w / w) A fiber molded sheet of Example S1(4) was obtained in the same manner as Blend (1), except that 1.43 g of aramid fiber (Kevlar (registered trademark) aramid fiber staple 1.7 dtex, average fiber diameter 15 μm, average fiber length 6 mm, moisture content 8.2%, manufactured by DuPont-Toray Co., Ltd.) was used as the main fiber material.

[0068] Blend (6): Recycled carbon fiber 97% (w / w), fibrous binder 3% (w / w) A fiber molding sheet of Example S1(5) was obtained in the same manner as Blend (1), except that the main fiber materials were 1.38 g of recycled carbon fiber from Blend (1) and 8.4 g of the fibrous binder from Example FB1.

[0069] <Example S2 (Fiber Molded Body Sheet)> Five types of fiber molded body sheets: Example S2(1), Example S2(2), Example S2(3), Example S2(4), Example S2(5), and Example S2(6) were obtained in the same manner as Examples S1(1) to S1(6), except that the fibrous binder of Example FB2 was used. Blend (1): 94% recycled carbon fiber (W / W), 6% fibrous binder (W / W) Blend (2): 94% carbon fiber (W / W), 6% fibrous binder (W / W) Blend (3): 94% glass fiber (W / W), 6% fibrous binder (W / W) Blend (4): 94% PET fiber (W / W), 6% fibrous binder (W / W) Blend (5): 94% aramid fiber (W / W), 6% fibrous binder (W / W) Blend (6): 97% recycled carbon fiber (W / W), 3% fibrous binder (W / W)

[0070] <Example S3 (Fiber Molded Body Sheet)> Five types of fiber molded body sheets: Example S3(1), Example S3(2), Example S3(3), Example S3(4), Example S3(5), and Example S3(6) were obtained in the same manner as Examples S1(1) to S1(6), except that the fibrous binder of Example FB3 was used. Blend (1): 94% recycled carbon fiber (W / W), 6% fibrous binder (W / W) Blend (2): 94% carbon fiber (W / W), 6% fibrous binder (W / W) Blend (3): 94% glass fiber (W / W), 6% fibrous binder (W / W) Blend (4): 94% PET fiber (W / W), 6% fibrous binder (W / W) Blend (5): 94% aramid fiber (W / W), 6% fibrous binder (W / W) Blend (6): 97% recycled carbon fiber (W / W), 3% fibrous binder (W / W)

[0071] <Comparative Example S1 (Fiber Molded Body Sheet)> Five types of fiber molded body sheets: Comparative Example S1(1), Comparative Example S1(2), Comparative Example S1(3), Comparative Example S1(4), Comparative Example S1(5), and Comparative Example S1(6) were obtained in the same manner as in Examples S1(1) to S1(6), except that the fibrous binder of Comparative Example FB1 was used. Blend (1): 94% recycled carbon fiber (W / W), 6% fibrous binder (W / W) Blend (2): 94% carbon fiber (W / W), 6% fibrous binder (W / W) Blend (3): 94% glass fiber (W / W), 6% fibrous binder (W / W) Blend (4): 94% PET fiber (W / W), 6% fibrous binder (W / W) Blend (5): 94% aramid fiber (W / W), 6% fibrous binder (W / W) Blend (6): 97% recycled carbon fiber (W / W), 3% fibrous binder (W / W)

[0072] <Comparative Example S2 (Fiber Molded Body Sheet)> Five types of fiber molded body sheets: Comparative Example S2(1), Comparative Example S2(2), Comparative Example S2(3), Comparative Example S2(4), Comparative Example S2(5), and Comparative Example S2(6) were obtained in the same manner as in Examples S1(1) to S1(6), except that the fibrous binder of Comparative Example FB2 was used. Blend (1): 94% recycled carbon fiber (W / W), 6% fibrous binder (W / W) Blend (2): 94% carbon fiber (W / W), 6% fibrous binder (W / W) Blend (3): 94% glass fiber (W / W), 6% fibrous binder (W / W) Blend (4): 94% PET fiber (W / W), 6% fibrous binder (W / W) Blend (5): 94% aramid fiber (W / W), 6% fibrous binder (W / W) Blend (6): 97% recycled carbon fiber (W / W), 3% fibrous binder (W / W)

[0073] <Comparative Example S3 (Fiber Molded Body Sheet)> Five types of fiber molded body sheets: Comparative Example S3(1), Comparative Example S3(2), Comparative Example S3(3), Comparative Example S3(4), Comparative Example S3(5), and Comparative Example S3(6) were obtained in the same manner as in Examples S1(1) to S1(6), except that the fibrous binder of Comparative Example FB3 was used. Blend (1): 94% recycled carbon fiber (W / W), 6% fibrous binder (W / W) Blend (2): 94% carbon fiber (W / W), 6% fibrous binder (W / W) Blend (3): 94% glass fiber (W / W), 6% fibrous binder (W / W) Blend (4): 94% PET fiber (W / W), 6% fibrous binder (W / W) Blend (5): 94% aramid fiber (W / W), 6% fibrous binder (W / W) Blend (6): 97% recycled carbon fiber (W / W), 3% fibrous binder (W / W)

[0074] <Comparative Example S4 (Fiber Molded Body Sheet)> Five types of fiber molded body sheets: Comparative Example S4(1), Comparative Example S4(2), Comparative Example S4(3), Comparative Example S4(4), Comparative Example S3(5), and Comparative Example S3(6) were obtained in the same manner as in Examples S1(1) to S1(6), except that the fibrous binder of Comparative Example FB4 was used. Blend (1): 94% recycled carbon fiber (W / W), 6% fibrous binder (W / W) Blend (2): 94% carbon fiber (W / W), 6% fibrous binder (W / W) Blend (3): 94% glass fiber (W / W), 6% fibrous binder (W / W) Blend (4): 94% PET fiber (W / W), 6% fibrous binder (W / W) Blend (5): 94% aramid fiber (W / W), 6% fibrous binder (W / W) Blend (6): 97% recycled carbon fiber (W / W), 3% fibrous binder (W / W)

[0075] <Comparative Example S5 (Fiber Molded Body Sheet)> Five types of fiber molded body sheets, Comparative Example S5(1), Comparative Example S5(2), Comparative Example S5(3), Comparative Example S5(4), Comparative Example S5(5), and Comparative Example S5(6), were obtained in the same manner as in Examples S1(1) to S1(6), except that the fibrous binder of Comparative Example FB5 was used. Blend (1): 94% recycled carbon fiber (W / W), 6% fibrous binder (W / W) Blend (2): 94% carbon fiber (W / W), 6% fibrous binder (W / W) Blend (3): 94% glass fiber (W / W), 6% fibrous binder (W / W) Blend (4): 94% PET fiber (W / W), 6% fibrous binder (W / W) Blend (5): 94% aramid fiber (W / W), 6% fibrous binder (W / W) Blend (6): 97% recycled carbon fiber (W / W), 3% fibrous binder (W / W)

[0076] The shapes, physical properties, and other properties of the fibrous binder, main fiber material, and fiber molded article, as well as various performance-related items, were measured and evaluated by the methods described below. Note that the values ​​and evaluations relating to the shapes, physical properties, and other properties, and performances shown in this disclosure can be determined by the following measurement and evaluation methods.

[0077] <Freeness of Fibrous Binder> The freeness of the fibrous binder was measured using a Canadian Standard Freeness Tester (manufactured by Tozai Seiki Co., Ltd.) The term "freeness" is also called "freeness" or "beating degree".

[0078] <Method for evaluating fiber properties> The average fiber length (mm), average fiber diameter (μm), Cryl ratio, and fine ratio (%) of the fibrous binder were measured as follows: The average fiber length (mm), average fiber diameter (μm), and moisture content (%) of the main fiber material were determined as follows.

[0079] <Average Fiber Length> (1) Fiber Length of Fibre Binder: Excluding fibers with a fiber length of less than 0.2 mm, fibers with a fiber length of 0.2 mm or more were diluted to 0.1 g of solids and 300 cc of slurry, and the fiber length was measured using an L&W Fiber Tester Plus Code 912 (manufactured by Lorentzen & Wettley). (2) Fiber Length of Main Fiber Material (Recycled Carbon Fiber): Considering the large variation in recycled carbon fiber, 20 fiber bundles were randomly selected, and each fiber bundle was measured using a vernier caliper, and the average value was calculated. (3) Fiber Length of Main Fiber Material (Other than Recycled Carbon Fiber): The average fiber length (or cut size) indicated by the supplier was used.

[0080] <Average fiber diameter> (1) Average fiber diameter of fibrous binder For fibers with a fiber length of 0.2 mm or more, excluding fibers with a fiber length of less than 0.2 mm, the fibrous binder was diluted to a solid content of 0.1 g and a slurry of 300 cc, and the diameter was measured using an L&W Fiber Tester Plus Code 912 (manufactured by Lorentzen & Wettley). (2) Average fiber diameter of main fiber material The fiber diameter of the main fiber material was determined by measuring 10 fibers randomly extracted from an image at 500x magnification using a Schottky field emission scanning electron microscope JSM-7900F (manufactured by JEOL Ltd.), and calculating the average value.

[0081] <Moisture Content of Main Fiber Material> The moisture content of the main fiber material was determined using a halogen moisture meter HB43 (manufactured by Mettler Toledo K.K.).

[0082] <Cryl Ratio> Ultraviolet or infrared light was irradiated onto a slurry of the fibrous binder, and the reduction in transmitted light from the incident light was determined for each ultraviolet or infrared light source. The reduction in ultraviolet light and the reduction in infrared light were used to calculate the cryl ratio based on the following formula 1. The test slurries were prepared by diluting the fibrous binder so that the solid content was 0.1 g and the slurry volume was 300 cc. An L&W Fiber Tester Plus Code 912 (Lorentzen & Wettley) was used as the measuring instrument.

[0083] <Formula 1> (CR) = (UVR) / (IRR) In formula 1, CR, UVR, and IRR are as follows: CR: Cryl ratio UVR: UV reduction amount IRR: Infrared reduction amount

[0084] <Fine Ratio> The ratio of fine fibers (fibers having a fiber length of less than 0.2 mm), that is, the fine ratio, was calculated using the following formula 2.

[0085] <Equation 2> (FR) = (FFL) / (WFL) × 100 (%) In equation 2, FR, FFL, and WFL are as follows: FR: fine ratio FFL: total length of fine fibers (fibers with a fiber length of less than 0.2 mm) WFL: total length of all fibers (fibers with a fiber length of less than 0.2 mm + fibers with a fiber length of 0.2 mm or more)

[0086] The FFL and WFL were measured using an L&W Fiber Tester Plus Code 912 (manufactured by Lorentzen & Wettley) after diluting the fibrous binder so that the solid content was 0.1 g and the slurry was 300 cc.

[0087] <Dimensions and Weight of Fiber Molded Product> The dimensions of the fiber molded product were measured using a ruler or the like as follows. The measurement samples of the fiber molded product were conditioned overnight in an atmosphere of 23°C and 50% RH. The weight of the fiber molded product after conditioning was measured using an electronic balance. The basis weight and density of the fiber molded product were calculated using the obtained measurements as follows.

[0088] <Thickness of Fiber Molded Article> The sheet thickness (unit: μm) of a sheet-like fiber molded article was measured using a thickness tester TM600 (manufactured by Kumagai Riki Kogyo Co., Ltd.) at a surface pressure of 100 kPa.

[0089] <Basis weight of fiber molded body> The basis weight (unit: g / m) of a sheet-shaped fiber molded body is calculated from its weight and area. 2 ) was sought.

[0090] <Density of fiber molded body> The density of the fiber molded body (unit: g / cm 3 ) is the basis weight of the fiber molding (unit: g / m 2The basis weight and sheet thickness of the fiber molding were calculated from the results of the measurements made by the above methods.

[0091] <Tensile strength of fiber molding> A sheet-like fiber molding was conditioned at 23°C and 50% humidity for 12 hours, and under this atmosphere, a test piece (width 15 mm, length 150 mm) was cut out, and the tensile strength (kN / m) was measured using an L&W Tensile Tester Code 066 (Lorentzen & Wettley).

[0092] The measurement results for the fibrous binder used as the binder are shown in Table 1-1. The measurement results for the sheet-shaped recycled carbon fiber molding of Blend (1) (94% recycled carbon fiber, 6% binder component) are shown in Table 1-2. The measurement results for the sheet-shaped carbon fiber molding of Blend (2) (94% carbon fiber, 6% binder component) are shown in Table 1-3. The measurement results for the sheet-shaped glass fiber molding of Blend (3) (94% glass fiber, 6% binder component) are shown in Table 1-4. The measurement results for the sheet-shaped PET fiber molding of Blend (4) (94% PET fiber, 6% binder component) are shown in Table 1-5. The measurement results for the sheet-shaped aramid fiber molding of Blend (5) (94% aramid fiber, 6% binder component) are shown in Table 1-6. The measurement results for the sheet-shaped recycled carbon fiber molding of Blend (6) (94% recycled carbon fiber, 6% binder component) are shown in Table 1-7.

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[0099]

Claims

1. A fiber molding comprising a main fiber material and a fibrous binder, the content ratio of the main fiber material to the fibrous binder being 1 to 20 parts by weight per 100 parts by weight of the main fiber material, and the acrylic ratio of the fibrous binder being 1.25 to 3.

00.

2. The fiber molding according to claim 1, wherein the average fiber length of the fibrous binder is 0.30 to 2.50 mm.

3. The fiber molding according to claim 1, wherein the main fiber material is one or more selected from the group consisting of carbon fiber, glass fiber, metal fiber, natural fiber, cellulose-based fiber, regenerated fiber, semi-synthetic fiber, and synthetic fiber.

4. The fiber molding according to claim 1, wherein the main fiber material is one or more fibers selected from the group consisting of carbon fiber, glass fiber, PET fiber, and aramid fiber.

5. The fiber molding according to claim 1, wherein the main fiber material is carbon fiber.

6. The fiber molding according to claim 5, wherein the carbon fibers are virgin carbon fibers, recycled carbon fibers, or a mixture thereof.

7. The fibrous molded article according to claim 1, wherein the fibrous binder is fibrillated cellulose fibers.

8. The fiber molding according to claim 1, wherein the fineness ratio of the fibrous binder is 95% or less.

9. A fiber-reinforced resin molding comprising the fiber molding according to any one of claims 1 to 8 and a resin component impregnated into the fiber molding.

10. A fibrous binder for a fibrous molded product, comprising fibrillated cellulose fibers, the fibrillated cellulose fibers having a cryl ratio of 1.25 to 3.00, and the fibrillated cellulose fibers having a fineness ratio of 95% or less.