WO2024176986A1 - Fiber sizing agent composition, fiber bundle, fiber product, and composite material - Google Patents

Abstract

The purpose of the present invention is to provide a fiber sizing agent composition having a pilling-inhibiting effect and excellent sizing performance.　The present invention is a fiber sizing agent composition containing a novolak epoxy resin (A1) and an aromatic nonionic surfactant (B1).

Description

Fiber sizing agent composition, fiber bundle, fiber product, and composite material

The present invention relates to a fiber bundling agent composition, a fiber bundle, a fiber product, and a composite material.

In recent years, composite materials made of matrix resins such as unsaturated polyester resin, phenolic resin, epoxy resin, and polypropylene resin and various fibers have been widely used in fields such as sports equipment, leisure goods, and aircraft. Fibers used in these composite materials include glass fiber, carbon fiber, ceramic fiber, metal fiber, mineral fiber, rock fiber, and slug fiber. A bundling agent is usually added to these fibers during the processing step to produce the composite material (see, for example, Patent Document 1).

International Publication No. 2013/146024

In a sizing process in which a sizing agent is applied to fibers to form a fiber bundle, it is required that a sizing liquid (sizing agent) penetrates between the fibers of the fiber bundle. However, with the sizing agent described in Patent Document 1, when the fiber bundle has a large number of fibers, the sizing liquid (sizing agent) does not penetrate sufficiently between the fibers, and therefore there is a problem that fuzzing of the fiber bundle cannot be sufficiently suppressed.
As a solution to this problem, a sizing agent containing a bisphenol-type epoxy resin was investigated. The result was a better fuzz suppression effect than the sizing agent described in Patent Document 1, but further improvement is required in terms of sizing ability.

The object of the present invention is to provide a fiber sizing agent composition that has a fuzz suppression effect and excellent sizing properties.

The present inventors conducted research aimed at achieving the above object and arrived at the present invention.
That is, the present invention is as follows.
[1] A fiber sizing agent composition comprising a novolac epoxy resin (A1) and an aromatic nonionic surfactant (B1).
[2] The fiber sizing agent composition according to [1], which contains 20 to 90% by weight of a novolac epoxy resin (A1) and 1 to 20% by weight of an aromatic nonionic surfactant (B1), based on the weight of the nonvolatile components contained in the fiber sizing agent composition.
[3] The fiber sizing agent composition according to [1] or [2], further comprising 5 to 70% by weight of a polyether-containing compound (C) based on the weight of the non-volatile components contained in the fiber sizing agent composition.
[4] The fiber sizing agent composition according to [3], wherein the polyether-containing compound (C) is a compound having an ester group obtained by reacting a diol (c2) with a dicarboxylic acid or an anhydride thereof (c1).
[5] The fiber sizing agent composition according to [4], wherein the dicarboxylic acid or anhydride thereof (c1) is an aromatic dicarboxylic acid or anhydride thereof.
[6] The fiber sizing agent composition according to [4] or [5], wherein the diol (c2) contains a diol (c21) having one or more polyoxyethylene groups consisting of two or more consecutive oxyethylene groups in one molecule, and the number of oxyethylene groups per polyoxyethylene group is 2 to 60.
[7] The fiber sizing agent composition according to any one of [1] to [6], wherein the epoxy group concentration in the nonvolatile components contained in the fiber sizing agent composition is 1.5 meq/g or more.
[8] A fiber bundle obtained by treating at least one type of fiber selected from the group consisting of carbon fibers, glass fibers, aramid fibers, ceramic fibers, metal fibers, mineral fibers, and slug fibers with the fiber sizing agent composition according to any one of [1] to [7].
[9] A textile product comprising the fiber bundle according to [8].
[10] A composite material comprising the fiber bundle according to [8] and a matrix resin.
[11] A composite material comprising the fiber product according to [9] and a matrix resin.

The present invention provides a fiber sizing agent composition that suppresses fuzzing and has excellent sizing properties.

FIG. 1 is a side view showing a schematic arrangement of an evaluation device and a carbon fiber bundle in the evaluation of fluff.

<Novolac-type epoxy resin (A1)>
Examples of the novolac type epoxy resin (A1) include bisphenol A novolac type epoxy resin, phenol novolac type epoxy resin, and cresol novolac type epoxy resin.
From the viewpoint of sizing ability, the novolac epoxy resin (A1) preferably has a viscosity of 5 Pa·s or more at 60°C (more preferably 10 Pa·s or more) or is a solid at 60°C.

As the novolac type epoxy resin (A1), a commercially available product may be used.
Commercially available bisphenol A novolac epoxy resins include "157S70" (solid at 60°C) manufactured by Mitsubishi Chemical Corporation.

Commercially available phenol novolac epoxy resins include "jER154" manufactured by Mitsubishi Chemical Corporation (viscosity at 60°C is 14 Pa·s), "EPICLON N-740" manufactured by DIC Corporation (viscosity at 60°C is 13 Pa·s), "EPICLON N-770" manufactured by DIC Corporation (solid at 60°C), "YDPN-638" manufactured by Nippon Steel Chemical & Material Co., Ltd. (viscosity at 60°C is 15 Pa·s), and "EPPN-201" manufactured by Nippon Kayaku Co., Ltd. (solid at 60°C).

Commercially available cresol novolac epoxy resins include "YDCN-700-7" (viscosity at 60°C is 30,000 Pa·s) manufactured by Nippon Steel Chemical & Material Co., Ltd., "EOCN-103S" (solid at 60°C) manufactured by Nippon Kayaku Co., Ltd., and "EOCN-104S" (solid at 60°C) manufactured by Nippon Kayaku Co., Ltd.

Of the novolac type epoxy resins (A1), from the viewpoint of bundling ability, phenol novolac type epoxy resins and cresol novolac type epoxy resins are preferred, and cresol novolac type epoxy resins are more preferred.
The novolac epoxy resin (A1) may be used alone or in combination of two or more kinds.

In this invention, "solid at 60°C" refers to an object that does not flow within 10 seconds after the container containing the object is tilted under a temperature condition of 60°C. The "tilted container" state refers to a state in which the container placed on a horizontal stand is tilted by 10° or more from before the container was tilted. "Before tilting" the container refers to a state in which the container was placed on a horizontal stand.

In the present invention, "viscosity at 60°C" refers to the viscosity measured at a strain of 1%, a frequency of 1 Hz, and a temperature of 60°C. The viscosity can be measured using a viscoelasticity measuring device (e.g., "MCR302" manufactured by Anton Paar Japan K.K.) with the measurement conditions set as follows:
Measurement mode: shear mode Plate: parallel plate (diameter 25 mm)
Distance between plates: 1 mm

The content of the novolac epoxy resin (A1) in the fiber sizing agent composition of the present invention is, from the viewpoint of sizing ability, preferably 20 to 90% by weight, and more preferably 30 to 85% by weight, based on the weight of the nonvolatile components contained in the fiber sizing agent composition.
In the present invention, the non-volatile component refers to the residue remaining after 1 g of a sample is placed in an uncovered glass petri dish and dried at 130° C. for 45 minutes in a circulating air dryer.

<Aromatic Nonionic Surfactant (B1)>
Examples of the aromatic nonionic surfactant (B1) include compounds obtained by adding alkylene oxide (AO) to a compound having an aromatic ring. Specific examples include compounds obtained by directly adding AO to alkyl (alkyl group having 1 to 18 carbon atoms) phenol, compounds obtained by directly adding AO to styrenated (1 to 10 mole) phenol, and compounds obtained by directly adding AO to styrenated (1 to 10 mole) cumylphenol. Examples of AO include those having 2 to 4 carbon atoms, such as EO (ethylene oxide), PO (1,2- or 1,3-propylene oxide), BO (1,2-, 1,3-, 2,3-, or 1,4-butylene oxide), and combinations of two or more of these.
The average number of moles of AO added is preferably 5 to 65. When a plurality of types of AO are contained, the average number of moles of AO added is the sum of the average number of moles of each AO added.

As the aromatic nonionic surfactant (B1), commercially available ones may be used. Examples of commercially available aromatic nonionic surfactants include Soprophor 796/P [manufactured by Solvay Nicca Co., Ltd.], Soprophor TSP/724 [manufactured by Solvay Nicca Co., Ltd.], and Soprophor TSP/461 [manufactured by Solvay Nicca Co., Ltd.] (all of which are PO and EO adducts of styrenated phenol).
The aromatic nonionic surfactant (B1) is preferably a compound obtained by directly adding AO to styrenated phenol (1 to 10 moles), and more preferably a PO and EO adduct of styrenated phenol. The aromatic nonionic surfactant (B1) may be used alone or in combination of two or more kinds.

From the viewpoint of the fuzz suppression effect, aromatic nonionic surfactants (B1) with an HLB (hydrophile-lipophile balance) value of 11 to 14 are preferred. The HLB value of aromatic nonionic surfactants (B1) is more preferably 11.5 to 13.7.

In the present invention, the HLB value is a value representing the balance between hydrophilicity and lipophilicity, and in the case of a single compound, it can be calculated from the following formula (1) (see, for example, "Synthesis and Application of Surfactants," p. 501, Maki Shoten, 1957; "Introduction to Surfactants," p. 212-213, Sanyo Chemical Industries, Ltd., 2007).
HLB value = 10 x (inorganic/organic) (1)
In formula (1), "inorganic/organic" represents the ratio between the inorganic value and the organic value of the compound, and this ratio can be calculated from the values given in the above-mentioned literature.
The organic value and inorganic value are calculated by setting the organic value to 20 per carbon atom, and using the values in the table on page 213 of the above-mentioned "Introduction to Surfactants" (the "numerical value" of the inorganic group, or the "inorganic value" of the organic and inorganic group).
_-CH3 group: organic value 20, inorganic value 0,
-CH ₂ - group: organic value 20, inorganic value 0,
= _CH2 group: organic value 20, inorganic value 1,
=CH- group: organic value 20, inorganic value 1,
Benzene ring: organic value 120, inorganic value 15,
-O- group: inorganic value 20,
-COO-: organic value 20, inorganic value 60,
-OH group: inorganic value 100,
-COOH group: organic value 20, inorganic value 150
Examples include:
In addition, in calculating the HLB value, the organic value and inorganic value shown below are used for the following components.
COO ⁻ M ⁺ : organic value 20, inorganic value 400 (Note that “M ⁺ ” is a counter ion of “COO ⁻ ” and represents a metal cation or an ammonium cation)
Si atom: organic value 0, inorganic value 0

The HLB value of the aromatic nonionic surfactant (B1) can be adjusted by adjusting the type and amount of the surfactant used. When the aromatic nonionic surfactant (B1) contains two or more surfactants, its HLB value can be calculated by weighted average. For example, when the aromatic nonionic surfactant (B1) contains M1 parts by weight of an aromatic nonionic surfactant (B11) having an HLB value of h1 and M2 parts by weight of an aromatic nonionic surfactant (B12) having an HLB value of h2, the HLB value of the aromatic nonionic surfactant (B1) can be calculated by the following formula.
HLB value of aromatic nonionic surfactant (B1)=(h1×M1+h2×M2)/(M1+M2)

The content of the aromatic nonionic surfactant (B1) in the fiber bundling composition of the present invention is preferably 1 to 20% by weight, and more preferably 5 to 15% by weight, based on the weight of the nonvolatile components contained in the fiber bundling composition, from the viewpoint of the fuzz suppression effect.

<Fiber sizing agent composition>
The fiber sizing agent composition of the present invention contains a novolac epoxy resin (A1) and an aromatic nonionic surfactant (B1).

According to the present invention, by containing a novolac epoxy resin (A1) having the above-mentioned characteristics and an aromatic nonionic surfactant (B1), it is possible to provide a fiber sizing agent composition that has excellent fuzz suppression and bundling properties. If the novolac epoxy resin (A1) is not contained, the bundling properties may be insufficient, and if the aromatic nonionic surfactant (B1) is not contained, the fuzz suppression effect may be insufficient.

The fiber bundling agent composition preferably contains 20 to 90% by weight of novolac epoxy resin (A1) and 1 to 20% by weight of aromatic nonionic surfactant (B1) based on the weight of the nonvolatile components contained in the fiber bundling agent composition, and more preferably contains 30 to 85% by weight of novolac epoxy resin (A1) and 5 to 15% by weight of aromatic nonionic surfactant (B1).

<Aliphatic Nonionic Surfactant (B2)>
The fiber sizing agent composition of the present invention may further contain an aliphatic nonionic surfactant (B2) as a component other than the novolac epoxy resin (A1) and the aromatic nonionic surfactant (B1). When the aliphatic nonionic surfactant (B2) is contained, the fuzzing suppression effect can be improved.

Examples of the aliphatic nonionic surfactant (B2) include AO adducts of aliphatic monoalcohols having 8 to 18 carbon atoms, AO adducts of higher fatty acids (having 12 to 24 carbon atoms), polyalkylene glycols (molecular weight 150 to Mw 6,000) obtained by adding AO (excluding EO) to glycols and reacting them with higher fatty acids, esters (molecular weight 250 to Mw 30,000) obtained by reacting higher fatty acids with polyhydric alcohols (polyhydric alcohols having dihydric or higher valences such as ethylene glycol, propylene glycol, glycerin, and sorbitan) and adding AO (excluding EO) to them, and polyhydric alcohol (carbon number 3 to 60) type nonionic surfactants (fatty acid (carbon number 3 to 60) esters of dihydric or higher polyhydric alcohols, etc.). The aliphatic nonionic surfactants (B2) may be used alone or in combination of two or more types.

As the aliphatic nonionic surfactant (B2), from the viewpoint of suppressing fluffing, an AO adduct of an aliphatic monoalcohol having 8 to 18 carbon atoms is preferred, and an aliphatic alkylene oxide adduct represented by the following general formula (2) (hereinafter also referred to as a "compound of general formula (2)") is more preferred.
R ¹ O(AO) _m H (2)
(In general formula (2), R ¹ is an aliphatic hydrocarbon group having 8 to 11 carbon atoms and having 3 or more methyl groups. AO is an alkyleneoxy group having 2 to 4 carbon atoms. m represents the average number of moles of AO added and is 1 to 10. The number of carbon atoms in R ¹ is preferably 9 or more from the viewpoint of further suppressing fuzzing of the fiber bundle.)

The aliphatic hydrocarbon group having 8 to 11 carbon atoms may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. Examples of the aliphatic hydrocarbon group having 8 to 11 carbon atoms include an aliphatic hydrocarbon group having three methyl groups, an aliphatic hydrocarbon group having four methyl groups, and an aliphatic hydrocarbon group having five or more methyl groups.
The "methyl group" in expressions such as the above "aliphatic hydrocarbon group having three methyl groups" refers to a _-CH3 contained in the aliphatic hydrocarbon group. For example, a 1-ethylbutyl group [ _CH3 ( _CH2 ) ₂ ( _CH3CH2 )CH-] has a total of two methyl groups because there is a _-CH3 at the end of both the ethyl group and _the butyl group.

The number of methyl groups in R ¹ in all the compounds of general formula (2) contained in the fiber sizing composition of the present invention is preferably 3.5 or more per molecule of the compound of general formula (2). When it is 3.5 or more, fluffing of fiber bundles can be further suppressed when the fiber sizing composition is used. In addition, the impregnation of the fiber sizing composition into the matrix resin can be improved. The number of methyl groups in R ¹ per molecule of the compound of general formula (2) is preferably 5 or less. The number of methyl groups in R ¹ per molecule of the compound of general formula (2) may be a decimal number.
The number of methyl groups in R ¹ can be calculated, for example, by carrying out ¹ H-NMR measurement and gas chromatography analysis of the raw material alcohol (R ¹ -OH) used in synthesizing the compound of general formula (2).
The method for producing the compound of formula (2) is not particularly limited, and the compound can be produced, for example, by the method described in the Production Examples of the present application. Commercially available products may also be used.

In general formula (2), (AO) is an alkyleneoxy group (oxyalkylene group) having 2 to 4 carbon atoms, specifically an ethyleneoxy group, a 1,2- or 1,3-propyleneoxy group, and a 1,2-, 1,3-, 2,3-, or 1,4-butyleneoxy group. Of these, an ethyleneoxy group is preferred. When a compound of general formula (2) has two or more (AO)s (m is 2 or more), the m (AO)s may be the same or different.

Specific examples of compounds of general formula (2) include EO adducts, PO adducts, BO adducts, random adducts of EO and PO, EO-PO block adducts, PO-EO block adducts, random adducts of EO and BO, EO-BO block adducts, and BO-EO block adducts of aliphatic alcohols having 8 to 11 carbon atoms. Of these, from the viewpoint of suppressing pilling, EO adducts of aliphatic alcohols having 8 to 11 carbon atoms are preferred, and EO adducts of decanol (having 3 or more methyl groups) are more preferred.

When the fiber bundling composition of the present invention contains an aliphatic nonionic surfactant (B2), the content is preferably 1 to 10% by weight or more, and more preferably 2 to 8% by weight or more, based on the weight of the nonvolatile components in the fiber bundling composition, from the viewpoint of fuzz suppression effect.

<Polyether-containing compound (C)>
The fiber sizing agent composition of the present invention may further contain a polyether-containing compound (C).

Examples of the polyether-containing compound (C) include compounds having one or more polyoxyalkylene groups in one molecule, and polyether-containing compounds having one or more polyoxyethylene groups in one molecule, with the number of oxyethylene groups (ethyleneoxy groups) per polyoxyethylene group being 2 to 60.

Examples of the polyether-containing compound (C) include ester compounds [such as compounds having an ester group obtained by reacting a diol (c2) with a dicarboxylic acid or its anhydride (c1)], urethane compounds [such as compounds obtained by reacting a polyol with a diisocyanate], and polyether diols. Among these, ester compounds are preferred.

As the ester compound, a compound having an ester group obtained by reacting a diol (c2) with a dicarboxylic acid or its anhydride (c1) is preferred. As the ester compound, the compounds described in JP-A-2022-169361 can be used.

Dicarboxylic acids or their anhydrides (c1) include aliphatic dicarboxylic acids (fumaric acid, etc.), aromatic dicarboxylic acids, and their anhydrides. Among these, aromatic dicarboxylic acids and their anhydrides are preferred. Dicarboxylic acids or their anhydrides (c1) may be used alone or in combination of two or more.

Examples of aromatic dicarboxylic acids include aromatic dicarboxylic acids having 8 to 14 carbon atoms (terephthalic acid, isophthalic acid, phthalic acid, phenylmalonic acid, phenylsuccinic acid, β-phenylglutaric acid, α-phenyladipic acid, β-phenyladipic acid, 2,2'- and 4,4'-biphenyldicarboxylic acid, naphthalenedicarboxylic acid, sodium 5-sulfoisophthalate, and potassium 5-sulfoisophthalate).
Among these, from the viewpoint of sizing ability, terephthalic acid, isophthalic acid and phthalic acid are more preferred.

The diol (c2) preferably contains a diol (c21) having one or more polyoxyethylene groups each consisting of two or more consecutive oxyethylene groups in one molecule, and the number of oxyethylene groups per polyoxyethylene group is 2 to 60.

Examples of the diol (c21) include polyethylene glycol (an example of a compound having one polyoxyethylene group) obtained by adding 1 to 59 moles of ethylene oxide (EO) to ethylene glycol, a compound obtained by adding 4 to 120 moles of EO to a compound having two hydroxyl groups (excluding ethylene glycol), and a compound obtained by adding 4 to 120 moles of EO to a primary amine (the above are examples of compounds having two polyoxyethylene groups in one molecule and having 2 to 60 oxyethylene groups per polyoxyethylene group).
Examples of the compound having two hydroxyl groups include aliphatic alkanediols, alicyclic diols, and aromatic ring-containing dihydric phenols. Among these, aromatic ring-containing dihydric phenols are preferred. Examples of aromatic ring-containing dihydric phenols include bisphenol A, bisphenol S, and hydroquinone.

The diol (c21) is preferably at least one diol selected from the group consisting of 4-120 mol EO adducts of aromatic ring-containing dihydric phenols, and more preferably 4-120 mol EO adducts of bisphenol A (the number of oxyethylene groups per polyoxyethylene group is 2-60).

The diol (c2) may contain, in addition to the diol (c21), another diol (c22). Examples of the other diol (c22) include an EO 2 mole adduct of an aromatic ring-containing dihydric phenol, ethylene glycol, and propylene glycol.
The weight of diol (c21) is preferably from 35 to 100% by weight, more preferably from 40 to 100% by weight, and even more preferably from 45 to 90% by weight, based on the weight of diol (c2).

An example of a method for producing an ester compound is to charge a dicarboxylic acid or its anhydride (c1) and a diol (c2) in a predetermined molar ratio, and distill off water while stirring at a reaction temperature of 100 to 250°C and a pressure of -0.1 to 1.2 MPa. In the method for producing an ester compound, it is preferable to add a catalyst in an amount of 0.05 to 0.5% by weight based on the weight of the ester compound. Examples of catalysts include paratoluenesulfonic acid, dibutyltin oxide, tetraisopropoxy titanate, and potassium oxalate titanate. From the viewpoints of reactivity and environmental impact, tetraisopropoxy titanate and potassium oxalate titanate are preferred, and potassium oxalate titanate is more preferred.

Examples of urethane compounds and polyether diols that can be used as the polyether-containing compound (C) include those described in JP 2022-169361 A.

The number average molecular weight of the polyether-containing compound (C) is preferably 1,000 to 10,000, and more preferably 1,000 to 9,000. The number average molecular weight is a value measured by gel permeation chromatography.

When the fiber sizing agent composition of the present invention contains a polyether-containing compound (C), the content thereof is preferably 5% by weight or more, and more preferably 10% by weight or more, based on the weight of the nonvolatile components in the fiber sizing agent composition, from the viewpoint of fiber opening. Also, from the viewpoint of sizing, the content of the polyether-containing compound (C) is preferably 70% by weight or less, and more preferably 50% by weight or less, based on the weight of the nonvolatile components in the fiber sizing agent composition. The content of the polyether-containing compound (C) is preferably 5 to 70% by weight, and more preferably 10 to 50% by weight, based on the weight of the nonvolatile components in the fiber sizing agent composition.

The fiber sizing agent composition of the present invention may further contain other components [resins (D) other than novolac epoxy resins (A1), surfactants (E) other than aromatic nonionic surfactants (B1) and aliphatic nonionic surfactants (B2), and additives (F), etc.] in addition to the above.

Examples of the resin (D) include epoxy resins other than the novolac type epoxy resin (A1), vinyl ester resins, and unsaturated polyester resins. As these resins, those described in JP 2022-169361 A can be used.

The surfactant (E) includes cationic surfactants, anionic surfactants and amphoteric surfactants.
Examples of the cationic surfactant include quaternary ammonium salt type [tetraalkyl (C1-30) ammonium salts (lauryl trimethyl ammonium chloride, didecyl dimethyl ammonium chloride, stearyl trimethyl ammonium bromide, etc.); polyoxyalkylene (C2-4) trialkyl (C1-30) ammonium salts (polyoxyethylene trimethyl ammonium chloride, etc.)] and amine salt type [inorganic acid salts or organic acid salts of aliphatic higher (C12-60) amines (lauryl amine, stearyl amine, etc.); and inorganic acid salts or organic acid salts such as EO adducts of aliphatic amines (C1-30)].

Anionic surfactants include carboxylic acids (saturated or unsaturated fatty acids having 8 to 22 carbon atoms) or their salts (sodium, potassium, ammonium, alkanolamine, etc.), higher alcohol (8 to 18 carbon atoms) sulfate ester salts, higher alkyl ether sulfate ester salts (sulfate ester salts of EO (1 to 10 moles) adducts of aliphatic alcohols having 8 to 18 carbon atoms, sulfate ester salts of AO adducts of alkylphenols, sulfate ester salts of AO adducts of arylalkylphenols, etc.), sulfonates (alkyl (1 to 20 carbon atoms) benzenesulfonates, alkyl (1 to 20 carbon atoms) naphthalenesulfonates, dialkyl sulfosuccinate (1 to 20 carbon atoms) esters, and α-olefin (12 to 18 carbon atoms) sulfonates, etc.), and phosphate ester salts (higher alcohol (8 to 60 carbon atoms) phosphate ester salts and higher alcohol (8 to 60 carbon atoms) EO adduct phosphate ester salts, etc.).

Examples of amphoteric surfactants include amino acid amphoteric surfactants (such as sodium propionate of higher alkylamine (carbon number 12-18)), betaine amphoteric surfactants (such as alkyl (carbon number 12-18) dimethyl betaine), sulfate ester salt type amphoteric surfactants (such as sodium sulfate of higher alkylamine (carbon number 8-18), sodium hydroxyethylimidazoline sulfate), sulfonate salt type amphoteric surfactants (such as pentadecylsulfotaurine, imidazoline sulfonic acid), and phosphate ester type amphoteric surfactants (phosphate ester amine salt of glycerin esterified with higher fatty acid (carbon number 8-22)).

As the surfactant (E), an anionic surfactant is preferred, and sulfate ester salts of AO adducts of alkylphenols, sulfate ester salts of AO adducts of arylalkylphenols, and mixtures thereof are more preferred.

The additive (F) may include a lubricant, a preservative, an antioxidant, and the like.
Examples of the smoothing agent include waxes (polyethylene, polypropylene, oxidized polyethylene, oxidized polypropylene, modified polyethylene, modified polypropylene, etc.), higher fatty acid alkyl (carbon number: 1 to 24) esters (methyl stearate, ethyl stearate, propyl stearate, butyl stearate, octyl stearate, stearyl stearate, etc.), higher fatty acids (myristic acid, palmitic acid, stearic acid, etc.), natural fats and oils (coconut oil, beef tallow, olive oil, rapeseed oil, etc.), and liquid paraffin.
Examples of preservatives include benzoic acids, salicylic acids, sorbic acids, quaternary ammonium salts, imidazoles, and the like.
Examples of the antioxidant include phenols (such as 2,6-di-t-butyl-p-cresol), thiodipropionates (such as dilauryl 3,3'-thiodipropionate), and phosphites (such as triphenyl phosphite).

The total content of components other than the novolac epoxy resin (A1), aromatic nonionic surfactant (B1), aliphatic nonionic surfactant (B2) and polyether-containing compound (C) is preferably 0 to 60% by weight, and more preferably 0 to 20% by weight, based on the weight of the nonvolatile components contained in the fiber sizing agent composition.

There are no particular limitations on the method for producing the fiber bundling agent composition of the present invention, but examples include a method in which novolac-type epoxy resin (A1), aromatic nonionic surfactant (B1), and, if necessary, aliphatic nonionic surfactant (B2), polyether-containing compound (C), resin (D), surfactant (E) and additive (F) are added to a mixing vessel, and the mixture is stirred at a temperature of preferably 20 to 150°C, more preferably 50 to 120°C until homogenous. There are no particular limitations on the order in which the components constituting the composition are added.

The epoxy group concentration of the non-volatile component in the fiber sizing agent composition of the present invention is preferably 1.5 meq/g or more. By having the epoxy group concentration of 1.5 meq/g or more, it is possible to provide a fiber sizing agent composition having excellent sizing properties. If the epoxy group concentration is less than 1.5 meq/g, the sizing properties may be insufficient. From the viewpoint of sizing properties, the epoxy group concentration is preferably 1.6 meq/g or more, more preferably 1.7 meq/g or more.
The epoxy group concentration can be adjusted by adjusting the type and amount of the novolac type epoxy resin (A1).
In the present invention, the epoxy group concentration can be determined from the epoxy equivalent measured by the method specified in JIS K 7236.

When the fiber sizing agent composition of the present invention contains a novolac epoxy resin (A1), an aromatic nonionic surfactant (B1), and a polyether-containing compound (C), the respective contents, based on the total weight of the novolac epoxy resin (A1), the aromatic nonionic surfactant (B1), and the polyether-containing compound (C), from an industrial viewpoint, are preferably 30 to 60% by weight of the novolac epoxy resin (A1), 5 to 15% by weight of the aromatic nonionic surfactant (B1), and 30 to 60% by weight of the polyether-containing compound (C), and more preferably 35 to 55% by weight of the novolac epoxy resin (A1), 5 to 15% by weight of the aromatic nonionic surfactant (B1), and 35 to 55% by weight of the polyether-containing compound (C).
Furthermore, when the fiber sizing agent composition contains a novolac epoxy resin (A1), an aromatic nonionic surfactant (B1), a polyether-containing compound (C), and an aliphatic nonionic surfactant (B2), the content of the aliphatic nonionic surfactant (B2) is preferably 3 to 10% by weight based on the total weight of the novolac epoxy resin (A1), the aromatic nonionic surfactant (B1), and the polyether-containing compound (C), from an industrial viewpoint.

The fiber sizing agent composition of the present invention can be used by dissolving or dispersing it in water and/or an organic solvent. Hereinafter, water and organic solvents are also referred to as "solvents".
By dissolving or dispersing the fiber sizing composition of the present invention in a solvent, it becomes easy to adjust the amount of the fiber sizing composition adhered to the fiber bundle to an appropriate amount.
The present invention also includes a solution or dispersion (fiber sizing agent solution/fiber sizing agent dispersion) obtained by dissolving or dispersing the fiber sizing agent composition of the present invention in a solvent.

Examples of the organic solvent include monohydric alcohols having 1 to 4 carbon atoms (methanol, ethanol, isopropanol, etc.), ketones having 3 to 6 carbon atoms (acetone, ethyl methyl ketone, methyl isobutyl ketone, etc.), glycols having 2 to 6 carbon atoms (ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, etc.), mono-lower alkyl ethers thereof (alkyl has 1 to 4 carbon atoms), dimethylformamide, aromatic hydrocarbons (toluene, xylene, etc.), alkyl acetates having 3 to 5 carbon atoms (methyl acetate, ethyl acetate, etc.), and the like.
The above-mentioned solvents may be used alone or in combination of two or more. Among the above-mentioned solvents, from the viewpoint of safety against fire, etc., preferred are water and mixed solvents of water and a water-miscible organic solvent (an organic solvent that can be uniformly mixed with water at a volume ratio of 1:1 at 25° C.), and more preferred is water.

Fibers to which the fiber sizing agent composition of the present invention can be applied include inorganic fibers (carbon fibers, glass fibers, ceramic fibers, metal fibers, mineral fibers, slug fibers, etc.) and organic fibers (aramid fibers, etc.). Of these, carbon fibers are preferred from the viewpoint of the strength of the molded body of the composite material using the fiber sizing agent composition and the fibers.

<Fiber bundle>
The fiber bundle of the present invention is a fiber bundle obtained by treating at least one type of fiber selected from the group consisting of carbon fibers, glass fibers, aramid fibers, ceramic fibers, metal fibers, mineral fibers, and slug fibers with the fiber sizing agent composition of the present invention.

The method for producing a fiber bundle of the present invention may include a method in which at least one type of fiber selected from the group consisting of carbon fibers, glass fibers, aramid fibers, ceramic fibers, metal fibers, mineral fibers, and slug fibers is treated with the fiber sizing agent composition or fiber sizing agent solution of the present invention to obtain a fiber bundle.
The fiber bundle of the present invention preferably has 3,000 to 50,000 fibers bundled together. The fiber sizing agent composition or fiber sizing agent solution of the present invention can sufficiently suppress fluffing even when the fiber bundle has a large number of fibers (20,000 or more).

Methods for treating the fibers include spraying and dipping.
The amount of the fiber sizing composition deposited on the fiber is preferably 0.05 to 5% by weight, more preferably 0.2 to 2.5% by weight, based on the weight of the fiber. When the amount of the fiber sizing composition deposited is within this range, the fiber sizing property is excellent.

<Textile products>
The textile product of the present invention includes the fiber bundle of the present invention. The textile product includes textile products obtained by processing the fiber bundle of the present invention, and includes woven fabrics, knitted fabrics, nonwoven fabrics (felt, mats, papers, etc.), chopped fibers, milled fibers, etc.

<Composite materials>
The composite material of the present invention contains the fiber bundle of the present invention and/or the fiber product of the present invention, and a matrix resin.

Examples of matrix resins include thermoplastic resins (polypropylene, polyamide, polyethylene terephthalate, polycarbonate, polyphenylene sulfide, etc.) and thermosetting resins (similar to the epoxy resins, unsaturated polyester resins, and vinyl ester resins that can be used as resin (D), as well as phenolic resins (such as those described in Patent No. 3723462)).

The composite material of the present invention may contain a catalyst, if necessary.
When the matrix resin is an epoxy resin that can be used as the resin (D), examples of the catalyst include known epoxy resin curing catalysts and curing accelerators (such as those described in JP-A-2005-213337), etc. When the matrix resin is an unsaturated polyester resin or vinyl ester resin, examples of the catalyst include peroxides (benzoyl peroxide, t-butyl perbenzoate, t-butyl cumyl peroxide, methyl ethyl ketone peroxide, 1,1-di(t-butylperoxy)butane, di(4-t-butylcyclohexyl)peroxydicarbonate, etc.) and azo compounds (azobisisovaleronitrile, etc.).

In the composite material of the present invention, the weight ratio of the matrix resin to the fiber bundles (matrix resin/fiber bundles) is preferably 10/90 to 90/10, more preferably 20/80 to 70/30, and particularly preferably 30/70 to 60/40, from the viewpoint of the strength of a molded product of the composite material, etc.
When the composite material contains a catalyst, the content of the catalyst is preferably 0.01 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, and particularly preferably 1 to 3 parts by weight, relative to 100 parts by weight of the matrix resin, from the viewpoint of the strength of a molded body of the composite material, etc.

The composite material of the present invention includes prepregs, molded articles, and the like.
The prepreg can be produced, for example, by impregnating a fiber bundle and/or a fiber product with a matrix resin that has been thermally melted (preferably at a melting temperature of 60 to 350° C.) or a matrix resin that has been diluted with a solvent (acetone, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, ethyl acetate, etc.). When a solvent is used, it is preferable to further remove the solvent by drying.

When the matrix resin is a thermoplastic resin, the prepreg can be molded by heating and then solidified at room temperature to form a molded article.
When the matrix resin is a thermosetting resin, the prepreg can be heated, molded, and cured to form a molded article.
These resins do not need to be completely cured, but are preferably cured to an extent that allows the molded product to maintain its shape. After molding, the resins may be further heated to be completely cured.
The method of heat molding is not particularly limited, and examples thereof include a filament winding molding method (a method in which a fiber is wound around a rotating mandrel under tension and then heat molded), a press molding method (a method in which prepreg sheets are laminated and then heat molded), an autoclave method (a method in which a prepreg sheet is pressed against a mold under pressure and then heat molded), and a method in which chopped fibers or milled fibers are mixed with a matrix resin and then injection molded.

The present invention will be further explained below with reference to examples, but the present invention is not limited to these. In the following, unless otherwise specified, "%" means "weight percent" and "parts" means "weight parts."

<Production Example 1: Production of bisphenol A EO 80 mol adduct (c21-3)>
In a pressure-resistant reaction vessel equipped with a stirrer, a heating/cooling device, and a dropping bomb, 228 parts (1 mol) of bisphenol A, 1000 parts of toluene, and 2 parts of potassium hydroxide were charged, and the pressure was set to -0.08 MPa. The temperature was raised to 130°C, and 3520 parts (80 mol) of EO were dropped over 6 hours while adjusting the pressure to 0.5 MPaG or less, and then the mixture was aged at 130°C for 3 hours. Next, after cooling to 100°C, 30 parts of an adsorption treatment agent "Kyoward 600" [manufactured by Kyowa Chemical Industry Co., Ltd.] were added, and the mixture was stirred and treated at 100°C for 1 hour, and the adsorption treatment agent was filtered to obtain an EO 80 mol adduct of bisphenol A (c21-3). The adduct (c21-3) is a diol having two polyoxyethylene groups, and the number of oxyethylene groups per polyoxyethylene group is 40.

<Production Example 2: Production of bisphenol A EO 40 mol adduct (c21-2)>
An EO 40 mol adduct (c21-2) of bisphenol A was obtained in the same manner as in Production Example 1, except that 1,000 parts of toluene was changed to 400 parts of toluene and 3,520 parts of EO was changed to 1,760 parts (40 parts by mole) in Production Example 1. The adduct (c21-2) is a diol having two polyoxyethylene groups, and the number of oxyethylene groups per polyoxyethylene group is 20.

<Production Example 3: Production of bisphenol A EO 120 mol adduct (c21-4)>
An adduct (c21-4) of bisphenol A with 120 moles of EO was obtained in the same manner as in Production Example 1, except that 1,000 parts of toluene was changed to 1,500 parts of toluene and 3,520 parts of EO was changed to 5,280 parts (120 parts by mole). The adduct (c21-4) is a diol having two polyoxyethylene groups, and the number of oxyethylene groups per polyoxyethylene group is 60.

<Production Example 4: Production of polyether-containing compound (C-1)>
1580 parts (5 mol parts) of bisphenol A EO 2-mol adduct (the number of oxyethylene groups per hydroxyl group is 1) "Newpol BPE-20" [manufactured by Sanyo Chemical Industries, Ltd.] (c22-1), 1590 parts (0.4 mol parts) of the adduct (c21-3) produced in Production Example 1, 996 parts (6 mol parts) of terephthalic acid (c1-1) and 3 parts of potassium oxalate titanate were reacted in a glass reaction vessel at 230°C under reduced pressure to 0.001 MPa while distilling off water, to obtain a polyether-containing compound (C-1) having a number average molecular weight (Mn) of 1850. This compound is a polyether-containing compound (ester compound) having an ester group.

<Production Examples 5 to 9: Production of Polyether-Containing Compounds (C-2) to (C-6)>
Each polyether-containing compound (C) was obtained in the same manner as in Production Example 4, except that the raw materials used (parts) in Table 1 were used. The results are shown in Table 1.

 

 

In Table 1, the raw materials used are as follows.
(c1-1): Terephthalic acid (c1-2): Fumaric acid (c21-1): EO 4 mole adduct of bisphenol A (number of oxyethylene groups per polyoxyethylene group is 2), trade name: "Newpol BPE-40", manufactured by Sanyo Chemical Industries, Ltd. (c21-2): EO 40 mole adduct of bisphenol A manufactured in Production Example 2 (c21-3): EO 80 mole adduct of bisphenol A manufactured in Production Example 1 (c21-4): EO 120 mole adduct of bisphenol A manufactured in Production Example 3 (c21-5): Polyethylene glycol (Mn: 2,000) (number of oxyethylene groups per polyoxyethylene group is 45)
(c22-1): 2-mol EO adduct of bisphenol A [one oxyethylene group per (poly)oxyethylene group, trade name: “Newpol BPE-20”, manufactured by Sanyo Chemical Industries, Ltd.]
(c22-2): ethylene glycol

<Production Example 10: Production of decanol-EO 6 mol adduct (B2-1)>
In a pressure-resistant reaction vessel equipped with a stirrer, a heating/cooling device, and a dropping bomb, 158 parts (1 mol) of "Decanol" [manufactured by KH Neochem Co., Ltd.] and 0.5 parts (0.009 mol) of potassium hydroxide were charged, and after nitrogen replacement, the vessel was sealed, heated to 70 ° C., and dehydrated under reduced pressure for 1 hour. The vessel was heated to 160 ° C., and 264 parts (6 mol) of EO were dropped over 5 hours while adjusting the pressure to 0.5 MPaG or less, and then aged at 160 ° C. for 2 hours. Next, after cooling to 70 ° C., 10 parts of the adsorption treatment agent "Kyoward 600" [manufactured by Kyowa Chemical Industry Co., Ltd.] were charged, and the mixture was stirred and treated at 70 ° C. for 1 hour, and the adsorption treatment agent was filtered to obtain a decanol-EO 6 mol adduct (B2-1).
The raw material compound used in this production example, decanol manufactured by KH Neochem Co., Ltd., was analyzed by ^1H -NMR and gas chromatography to confirm that it was an alcohol in which a hydroxyl group was bonded to a decyl group (an aliphatic hydrocarbon group having 10 carbon atoms), and that the number of methyl groups in ^R1 per molecule of the compound was 3.5.
Therefore, the decanol-EO 6-mol adduct (B2-1) obtained in this Production Example is a compound represented by the above general formula (2), in which R ¹ is a decyl group (the number of methyl groups in R ¹ per molecule of the compound is 3.5), (AO) is an ethyleneoxy group, and m is 6.

<Examples 1 to 10 and Comparative Examples 1 to 5>
Into a reaction vessel equipped with a stirrer, a heating/cooling device, a thermometer, and a dropping funnel, the types and amounts of materials shown in Table 2 [novolac type epoxy resin (A1) or bisphenol A type epoxy resin (A'), aromatic nonionic surfactant (B1), polyether-containing compound (C), and aliphatic nonionic surfactant (B2)] were charged, and the mixture was stirred for 5 minutes while heating to obtain a fiber sizing agent composition.
Next, water was dropped from a dropping funnel into the fiber sizing agent composition over 1 hour to prepare fiber sizing agent solutions (X1) to (X10), (X'1) to (X'3) and (X'5), which are dispersions of the fiber sizing agent composition with a solid content concentration of 40%. Here, the solid content refers to the residue after 1 g of the sample was heated and dried in a circulating air dryer at 130°C for 45 minutes in a glass petri dish without a lid. The sizing ability, fluffing and strength of the molded body of the carbon fiber bundles prepared using the fiber sizing agent solutions (X1) to (X10), (X'1) to (X'3) and (X'5) were evaluated by the following method. The results are shown in Table 2. Note that for Comparative Example 4, the composition was not dispersed and a fiber sizing agent solution was not obtained, so the sizing ability, fluffing and strength of the molded body could not be evaluated (Table 2 states that it was not measurable).

The materials used in the preparation of fiber sizing agent solutions in the Examples and Comparative Examples are as follows.
<Novolac-type epoxy resin (A1)>
(A1-1): Cresol novolac type epoxy resin [manufactured by Nippon Steel Chemical & Material Co., Ltd., "YDCN-700-7", viscosity at 60°C is 30,000 Pa·s, epoxy group concentration is 5.00 meq/g]
(A1-2): Phenol novolac type epoxy resin [manufactured by DIC Corporation, "EPICLON N-740", viscosity at 60°C is 13 Pa·s, epoxy group concentration is 5.49 meq/g]
<Bisphenol A Type Epoxy Resin (A')>
(A'-1): Bisphenol A type epoxy resin [manufactured by DIC Corporation, "EPICLON 1050", viscosity at 60°C is 4000 Pa·s, epoxy group concentration is 2.11 meq/g]
(A'-2): Bisphenol A type epoxy resin [manufactured by Mitsubishi Chemical Corporation, "jER828", viscosity at 60°C is 0.2 Pa·s, epoxy group concentration is 5.29 meq/g]

<Aromatic Nonionic Surfactant (B1)>
(B1-1): Propylene oxide/ethylene oxide adduct of styrenated phenol [trade name: "Soprophor 796/P", manufactured by Solvay Nicca Co., Ltd., HLB value: 13.7, 3 moles of styrene per mole of phenol]
(B1-2): Propylene oxide/ethylene oxide adduct of styrenated phenol [product name: "Soprophor TSP/724", manufactured by Solvay Nicca Co., Ltd., HLB value is 11.9]

<Polyether-containing compound (C)>
(C-1): Polyether-containing compound (ester compound) produced in Production Example 4
(C-2): Polyether-containing compound (ester compound) produced in Production Example 5
(C-3): Polyether-containing compound (ester compound) produced in Production Example 6
(C-4): Polyether-containing compound (ester compound) produced in Production Example 7
(C-5): Polyether-containing compound (ester compound) produced in Production Example 8
(C-6): Polyether-containing compound (ester compound) produced in Production Example 9

<Aliphatic Nonionic Surfactant (B2)>
(B2-1): EO 6 mole adduct of decanol produced in Production Example 10

[Measurement of Resin Viscosity at 60° C.]
The viscosity at 60° C. of the novolac type epoxy resin (A1) and the bisphenol A type epoxy resin (A′) was measured using a viscoelasticity measuring device (MCR302, manufactured by Anton Paar Japan KK) under the following conditions.
Measurement mode: Shear mode Conditions: Strain 1%, Frequency 1Hz
Plate: Parallel plate (diameter 25 mm)
Distance between plates: 1 mm

[Evaluation of emulsion stability]
For the fiber sizing agent solutions of the examples and comparative examples, the median diameter was measured using a laser diffraction/scattering type particle size distribution measuring device LA-950 manufactured by Horiba, Ltd., and evaluation was performed based on the following evaluation criteria. The results are shown in Table 2. The refractive index conditions were 1.470 (particles) and 1.333 (dispersion medium). A smaller median diameter is preferable.
<Evaluation criteria>
◯: Median diameter is 0.150 μm or less △: Median diameter is more than 0.150 μm to 0.200 μm or less ×: Median diameter is more than 0.200 μm or emulsification is not possible

[Evaluation of bundle property, fluffing and molded body strength]
<Production of carbon fiber bundles for evaluation tests>
Water was added to the fiber sizing agent solution obtained in each Example and Comparative Example (except Comparative Example 4) so that the solid content concentration was 1.5% to prepare a dispersion, and untreated carbon fibers (24,000 filaments) were immersed in the dispersion of the fiber sizing agent composition to impregnate the dispersion. The carbon fibers were then removed from the dispersion of the fiber sizing agent composition and dried with hot air at 180°C for 3 minutes to obtain a carbon fiber bundle. The carbon fiber bundle was prepared so that the amount of solids contained in the dispersion of the fiber sizing agent composition attached to the fibers (percentage based on the weight of the carbon fibers before immersion) was 1.5%. The carbon fiber bundle was subjected to an evaluation test for sizing ability and fluffing.

<Focusing evaluation test>
The bundle of test carbon fibers was evaluated for bundle property according to JIS L 1096:2010 8.21.1 A method (45° cantilever method). That is, the carbon fiber bundle obtained under the treatment conditions specified in the JIS was evaluated by the cantilever method. The larger the measured value (cm), the better the bundle property. The bundle property value measured by this evaluation method is preferably 20 cm or more, and particularly preferably 25 cm or more. If it is 19 cm or less, the bundle property improvement effect is insufficient.

<Fuzziness evaluation test>
(1) Description of the evaluation apparatus As shown in Fig. 1, five stainless steel rods (1A, 1B, 1C, 1D, 1E) with a smooth surface and a diameter of 10 mm, whose temperature was adjusted to 25°C, were arranged in parallel with each other so that the horizontal distance between adjacent stainless steel rods was 50 mm, and so that the carbon fiber bundles 4 passed in a zigzag manner while in contact with the stainless steel rods 1A, 1B, 1C, 1D, 1E. The horizontal direction is the direction indicated by the arrow X-X' in the figure, which is parallel to the horizontal plane HL.
The straight line connecting the centers of the stainless steel rods 1A, 1C, and 1E through which the carbon fiber bundle 4 passes for the first, third, and fifth time, and the straight line connecting the centers of the stainless steel rods 1B and 1D through which the carbon fiber bundle 4 passes for the second and fourth time, were arranged to be parallel to a horizontal plane. Also, before and after the passage of the second to fourth stainless steel rods 1B and 1D, the straight line which is the traveling direction of the carbon fiber bundle before the passage and the straight line which is the traveling direction of the carbon fiber bundle after the passage were arranged to form an angle of 120 degrees (for example, the angle formed by the straight line parallel to the traveling direction of the carbon fiber bundle passing between the first stainless steel rod 1A and the second stainless steel rod 1B and the straight line parallel to the traveling direction of the carbon fiber bundle passing between the second stainless steel rod 1B and the third stainless steel rod 1C was 120 degrees).
The unwinding roll 2 and the winding roll 3 were set to rotate in the directions of the arrows drawn near each roll.

(2) Measurement of fluff weight The fluff weight was measured using a test carbon fiber bundle according to the following procedure.
The carbon fiber bundle 4 was hung in a zigzag pattern between stainless steel rods 1A, 1B, 1C, 1D, and 1E, and after passing stainless steel rod 1E, in a region (region 5A 10 cm upstream from winding start point 3A of winding roll 3) immediately before being taken up by winding roll 3, the carbon fiber bundle 4 was sandwiched in the thickness direction of the fiber bundle (the vertical direction in the figure) between two 10 cm x 10 cm rectangular urethane foam sheets with a load of 1 kg. In this example, the carbon fiber bundle is transported from unwinding roll 2 to winding roll 3, so the "upstream side" means the upstream side in the transport direction, that is, the unwinding roll 2 side.
The unwinding tension from the unwinding roll 2 was 9.8 N (1 kgf), and the carbon fiber bundle 4 sandwiched between the urethane foam was wound around the winding roll 3 at a speed of 1 m/min for 5 minutes. During this time, the weight of the fluff adhering to the two sheets of urethane foam was measured, and evaluation was performed based on the following evaluation criteria. The smaller the amount of fluff, the more effectively the fluffing was suppressed.
<Evaluation criteria>
◎: The amount of fluff is 0.5 mg or less. ◯: The amount of fluff is more than 0.5 mg to 2 mg or less. ×: The amount of fluff is more than 2 mg.

<Evaluation test of molded body strength>
The above test carbon fiber bundles were used for evaluation according to the following procedure.
(1) Preparation of test piece The carbon fiber bundle was placed in a mold so that the volume fraction (Vf) of the carbon fiber was 60%, and a matrix resin (see below for composition) was poured in, followed by vacuum degassing while heating. After degassing, the bundle was set in a press machine and heated while applying pressure to harden the resin, producing a flat plate with a width of 6 mm and a thickness of 2.5 mm, which was then cut to a length of 18 mm to prepare a test piece.
(Composition of matrix resin placed in mold)
Bisphenol A type epoxy resin (Ep828, manufactured by Japan Epoxy Resins Co., Ltd.) 100 parts by weight Boron trifluoride monoethylamine (manufactured by Stella Chemifa Co., Ltd.) 3 parts by weight (molding conditions)
Degassing: under vacuum (-0.08 MPa or less), 70°C x 4 hours Molding: press pressure (4.9 MPa), 170°C x 1 hour After cure: 170°C x 2 hours (2) Measurement of molded body strength (CFRP strength) The ILSS (interlaminar shear strength) of the obtained test pieces (molded bodies) was measured in accordance with JIS K 7078. A higher measured value indicates a higher strength and a higher adhesion between the fiber and the matrix resin.
<Evaluation criteria>
◎: ILSS is 90 MPa or more ◯: ILSS is 80 MPa or more to less than 90 MPa ×: ILSS is less than 80 MPa

 

 

As shown in Table 2, it was found that the use of the fiber sizing agent compositions of the Examples could suppress fuzzing and provide significantly excellent sizing properties.
The fiber sizing agent solutions of the above examples and the fiber sizing agent compositions constituting them are within the scope of the present invention. Therefore, it is understood that the present invention can provide a fiber sizing agent that suppresses fuzzing and has excellent sizing properties.

1A, 1B, 1C, 1D, 1E Stainless steel rod 2 Unwinding roll 3 Winding roll 3A Winding start point 4 Carbon fiber bundle 5A Region HL 10 cm upstream from 3A Horizontal surface

Claims (11)

A fiber sizing agent composition comprising a novolac epoxy resin (A1) and an aromatic nonionic surfactant (B1). The fiber bundling agent composition according to claim 1, which contains 20 to 90% by weight of novolac-type epoxy resin (A1) and 1 to 20% by weight of aromatic nonionic surfactant (B1), based on the weight of the nonvolatile components contained in the fiber bundling agent composition. The fiber sizing agent composition according to claim 1 further contains 5 to 70% by weight of a polyether-containing compound (C) based on the weight of the non-volatile components contained in the fiber sizing agent composition. The fiber sizing agent composition according to claim 3, wherein the polyether-containing compound (C) is a compound having an ester group obtained by reacting a diol (c2) with a dicarboxylic acid or its anhydride (c1). The fiber sizing agent composition according to claim 4, wherein the dicarboxylic acid or its anhydride (c1) is an aromatic dicarboxylic acid or its anhydride. The fiber sizing agent composition according to claim 4, wherein the diol (c2) contains a diol (c21) having one or more polyoxyethylene groups each consisting of two or more consecutive oxyethylene groups in one molecule, and the number of oxyethylene groups per polyoxyethylene group is 2 to 60. The fiber bundling agent composition according to claim 1, wherein the epoxy group concentration in the non-volatile components contained in the fiber bundling agent composition is 1.5 meq/g or more. A fiber bundle obtained by treating at least one type of fiber selected from the group consisting of carbon fiber, glass fiber, aramid fiber, ceramic fiber, metal fiber, mineral fiber, and slug fiber with the fiber sizing agent composition according to any one of claims 1 to 7. A textile product comprising the fiber bundle according to claim 8. A composite material comprising the fiber bundle according to claim 8 and a matrix resin. A composite material comprising the fiber product according to claim 9 and a matrix resin.

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