Microplastic fiber reducing agent for fibers

Abstract

To obtain a new agent for reducing microplastic fibers for fibers, capable of reducing the amount of the microplastic fibers generated when fibers or fiber products containing synthetic fibers are washed, etc., and to provide a method for reducing the microplastic fibers.SOLUTION: A cationic polymer (component (a)) having a specific structural unit; The fiber or fiber product containing the synthetic fiber is treated by using the microplastic fiber reducing agent for the fiber.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a microplastic fiber reducing agent for textiles and a method for reducing microplastic fibers for textiles. [Background technology]

[0002] In recent years, there has been growing concern about the impact of plastics on the marine environment, including the risk that tiny plastic particles, such as microplastic beads, may end up in the ocean and become ingested by sea turtles, seabirds, and fish (and ultimately humans). Microplastic pollution also includes microfibers (less than 5mm in length) from synthetic clothing. These synthetic microfibers are shed during textile cleaning (washing, scouring, etc.) and are released into the ocean, coasts, rivers, lakes, etc., and some of them are thought to end up in the soil.

[0003] It is known to use cellulose derivatives as care compounds that can reduce the pilling and fuzzing of clothing. For example, Patent Document 1 discloses a clothing care composition containing (a) a specific nonionic surfactant, (b) a polysaccharide polymer, and (c) a surfactant other than component (a). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-100723 Summary of the Invention [Problem to be solved by the invention]

[0005] However, it has been found that simply reducing friction at the contact points between fibers is not sufficient to suppress the generation of microplastic fibers that are generated from fibers, for example, when the fibers are washed with water. The present invention provides a novel microplastic fiber-reducing agent for fibers that reduces the amount of microplastic fibers generated from fibers, for example, when the fibers are washed with water, a fiber treatment composition containing the microplastic fiber-reducing agent for fibers, and a method for reducing microplastic fibers. Microplastic fibers in the present invention refer to fibrous microplastics, with fiber lengths generally ranging from 0.1 μm to less than 5 mm. Microplastic fibers are known to be contained in wastewater from washing textile products containing synthetic fibers, and are thought to be formed by the shedding of some of the synthetic fibers from such textile products. Microplastic fibers refer to synthetic fiber waste and laundry waste. The method for reducing microplastic fibers in the present invention means a method for reducing the generation and emission of microplastic fibers from fibers and textile products. In the present invention, "fiber" refers to a fiber containing one or more types of synthetic fibers, and may also contain one or more types of non-synthetic fibers. The fiber in the present invention may be in the form of a thread or a test piece having a predetermined size. Furthermore, products manufactured using the fiber are referred to as textile products. The "fiber" targeted by the microplastic fiber-reducing agent for fibers and the microplastic fiber reduction method of the present invention includes both the fiber and the textile product manufactured using the fiber. In the present invention, treating fibers refers to exerting a physical and / or chemical effect on fibers via the microplastic fiber-reducing agent for fibers of the present invention or a fiber treatment composition containing the microplastic fiber-reducing agent described below. The treatment referred to here includes, for example, a washing process that actually removes dirt and impurities from fibers during the washing process. However, the present invention is not limited to washing and may include any physical and / or chemical action on fibers that enables the removal of dirt and impurities from fibers during the manufacturing process of fibers themselves or the recycling process of textile products. Specifically, the treatment in the present invention is preferably at least one of a washing process or a fiber scouring process. For example, the washing process includes at least one of a washing process (also referred to as a cleaning process), a rinsing process, a treatment process using a laundry aid such as a fabric softener, or a spin-drying process. Fiber scouring is the removal of impurities adhering to fibers before dyeing, for example, using a surfactant or the like. The washing process in the present invention may be performed using a machine such as a washing machine, or by hand washing. [Means for solving the problem]

[0006] The present invention relates to a microplastic fiber reducing agent for textiles, which comprises a cationic polymer (hereinafter also referred to as component (a)) and an anionic surfactant (hereinafter also referred to as component (b)).

[0007] The present invention also relates to a method for reducing microplastic fibers, which comprises a step of contacting fibers with a microplastic reducing agent for fibers comprising component (a) and component (b), or a microplastic reducing agent composition for fibers containing the microplastic reducing agent for fibers. [Effects of the Invention]

[0008] According to the present invention, there are provided a novel microplastic fiber reducing agent for fibers that reduces the amount of microplastic fibers generated from fibers, for example, during cleaning, a fiber treatment composition containing the microplastic fiber reducing agent for fibers, and a method for reducing microplastic fibers. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, microplastic fibers will also be referred to as "MPF." Unless otherwise specified, the reason why each preferred embodiment is preferred is "from the perspective of further reducing microplastic fibers (MPF) generated from the fibers." The same reason will also be described as "from the perspective of improving MPF reduction ability."

[0010] <MPF reducing agent for textiles> The MPF reducing agent for fibers of the present invention contains component (a) and component (b). The MPF reducing agent for fibers of the present invention may consist essentially of component (a) and component (b).

[0011] The MPF reducer for fibers of the present invention may be an MPF ​​reducer for textile products. The MPF reducer for fibers of the present invention may also be an MPF ​​reducer for synthetic fibers, or even an MPF ​​reducer for synthetic textile products.

[0012] Furthermore, the MPF reducer for fibers of the present invention may be an MPF ​​generation reducer for fibers that reduces the amount of MPF generated from fibers, for example, when synthetic fibers are washed.

[0013] <Cationic polymer> In the present invention, a cationic polymer refers to a polymer having a positive charge density, i.e., a polymer in which the sum of the cationic charge density of the polymer and the anionic charge density of the polymer is a positive value. Here, the cationic charge density (meq / g) of a polymer is expressed in eq units by multiplying the total number of moles of cationic groups and substituents that can become cations by adding protons in water contained in 1 mol of the polymer by the positive charge valence when each cationic group and substituent becomes a cationic group, and dividing this value by the mass (kg) of 1 mol of the polymer. Furthermore, the anionic charge density (meq / g) of a polymer is expressed in eq units by multiplying the total number of moles of anionic groups and substituents that can become anions by removing protons in water contained in 1 mol of the polymer by the negative charge valence when each anionic group and substituent becomes an anionic group, and dividing this value by the mass (kg) of 1 mol of the polymer (a negative value). In the present invention, both the cationic charge density of a polymer and the anionic charge density of a polymer are calculated values. From the viewpoint of improving the MPF reduction ability, the cationic group is preferably one or more selected from (primary to quaternary) ammonio groups (hereinafter sometimes referred to as ammonio groups) and amino groups (-NH2 groups). The amino groups are converted into cationic ammonio groups (-NH2 groups) by adding a proton in water depending on the pH. + In the present invention, cationic groups are included in the cationic groups. That is, when calculating the cationic charge density, 1 mol of amino groups is calculated as +1 eq. In the following explanation, for convenience, cationic groups include both ammonio groups and amino groups, and are explained as ammonio groups.

[0014] The weight average molecular weight of the cationic polymer of the present invention is preferably 100,000 or more, more preferably 1,000,000 or more, even more preferably 3,000,000 or more, and still more preferably 5,000,000 or more, from the viewpoint of improving the MPF reduction ability, and is preferably 50,000,000 or less, more preferably 30,000,000 or less, even more preferably 20,000,000 or less, and still more preferably 10,000,000 or less, from the viewpoint of improving the fluidity of the treatment liquid described below.

[0015] The weight average molecular weight of the cationic polymer is calculated in terms of polyethylene glycol by GPC (gel permeation chromatography) under the following measurement conditions. Column: TSKgel α-M Eluent: 50mmol / L LiBr, 1% CH3COOH, ethanol / water = 3 / 7 ·Temperature: 40℃ ·Flow rate: 0.6mL / min

[0016] The charge density of the cationic polymer of the present invention is preferably +0.1 meq / g or more, more preferably +0.3 meq / g or more, even more preferably +0.5 meq / g or more, and still more preferably +0.8 meq / g or more, from the viewpoint of improving the MPF reduction ability, and is preferably less than +20 meq / g, more preferably less than +15 meq / g, even more preferably +10 meq / g or less, and still more preferably +3.5 meq / g or less, from the viewpoint of improving the adsorption to fibers.

[0017] The cationic polymer in the present invention is a polymer represented by the following general formula (1) from the viewpoint of improving the MPF reduction ability: [ka] (In the formula, R 1 represents a hydrogen atom or a methyl group. 2 , R 3 and R 4 each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; X represents -O- or -NH-; m represents an integer of 1 to 4; Z - indicates the counter anion.) It is preferable that the compound contains an ammonio group represented by the following formula:

[0018] Z -is a counter anion of the ammonio group in general formula (1), and is not particularly limited. From the viewpoint of improving MPF reduction ability, examples include one or more anions selected from alkyl sulfate ions having 1 to 3 carbon atoms, (1 / 2) sulfate ions, (1 / 3) phosphate ions, fatty acid ions having 1 to 3 carbon atoms, and halide ions. Among these, from the same viewpoint, one or more anions selected from alkyl sulfate ions and halide ions having 1 to 3 carbon atoms are preferred. Examples of alkyl sulfate ions having 1 to 3 carbon atoms include one or more anions selected from methyl sulfate ions and ethyl sulfate ions. Examples of halide ions include one or more anions selected from fluoride ions, chloride ions, bromide ions, and iodide ions. From the same viewpoint, the anion is preferably one or more anions selected from methyl sulfate ions, ethyl sulfate ions, chloride ions, and bromide ions, more preferably one or more anions selected from methyl sulfate ions, ethyl sulfate ions, and chloride ions. The counter anion of the ammonio group in general formula (1) may be of one type alone or of two or more types.

[0019] R in general formula (1) 1 From the viewpoint of improving the MPF reduction ability, R in general formula (1) is preferably a methyl group. 2 ~R 4 From the same viewpoint, each of X in general formula (1) is independently a hydrogen atom, preferably a methyl group or an ethyl group. From the same viewpoint, X in general formula (1) is preferably -O-. From the same viewpoint, m in general formula (1) is preferably 2 or 3, more preferably 2.

[0020] The cationic polymer in the present invention is, for example, a polymer represented by the following general formula (1a): [ka] (In the formula, R 1 , R 2 , R 3 , R 4 , X, m and Z - (These are the same as above.) It can be obtained by polymerizing a monomer represented by the following formula (also called olefin (1a)):

[0021] The cationic polymer of the present invention may be copolymerized with other monomers having a double bond (also referred to as other olefins) as appropriate. The other olefins are not limited, but from the viewpoint of improving the MPF reduction ability, it is preferable to use a monomer represented by the following general formula (2a): [ka] (In the formula, R 5 represents a hydrogen atom or a methyl group. 6 and R 7 each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. A monomer represented by the general formula (2) (also called olefin (2a)) is copolymerized to form a copolymer represented by the general formula (2) [ka] (In the formula, R 5 , R 6 and R 7 (These are the same as above.) By introducing a constitutional unit represented by general formula (3) [ka] (In the formula, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , X, m and Z - p1 and q1 represent the content of structural units derived from olefin (1a) and olefin (2a), respectively, and 0 <p1<1かつ0<q1<1かつp1+q1≦1である。) A structural unit represented by the following formula may be introduced.

[0022] R in general formulas (2a), (2) and (3) 5is preferably a hydrogen atom from the viewpoint of improving the MPF reduction ability.

[0023] R in general formulas (2a), (2) and (3) 6 and R 7 Examples of the hydrocarbon group include a linear alkyl group, a branched alkyl group, and a cyclic alkyl group. From the viewpoint of improving the MPF reduction ability, a linear alkyl group is preferred, and specific examples thereof include a methyl group, an ethyl group, an isopropyl group, and a butyl group. From the same viewpoint, a group selected from a methyl group and an ethyl group is preferred.

[0024] The copolymerization of the olefin (1a) and the olefin (2a) may be carried out under ordinary copolymerization conditions, for example, alternating copolymerization, block copolymerization, or random copolymerization.

[0025] From the viewpoint of improving the MPF reduction ability, p1 in general formula (3) is preferably 0.05 or more, more preferably 0.1 or more, and even more preferably 0.15 or more, and from the viewpoint of economic efficiency, it is preferably 0.8 or less, more preferably 0.6 or less, and even more preferably 0.4 or less. Furthermore, from the viewpoint of improving the MPF reduction ability, q1 in general formula (3) is preferably 0.2 or more, more preferably 0.4 or more, and even more preferably 0.6 or more, and from the same viewpoint, it is preferably 0.9 or less, more preferably 0.8 or less, and even more preferably 0.7 or less.

[0026] Further, an olefin (1a) and an olefin of the following general formula (4a) are copolymerized to obtain a copolymer of the following general formula (4): [ka] (In the formula, R 8 represents a hydrogen atom or a methyl group. 9 represents a hydrogen ion, an alkali metal ion or (1 / 2) alkaline earth metal ion, an ammonium ion, or an alkylammonium ion having an alkyl group having 1 to 4 carbon atoms. A monomer represented by the general formula (4) (also called olefin (4a)) is copolymerized to form a copolymer represented by the general formula (4) [ka] (In the formula, R 8 and R 9 (These are the same as above.) By introducing a constitutional unit represented by the general formula (5) [ka] (In the formula, R 1 , R 2 , R 3 , R 4 , R 8 , R 9 , X, m and Z - p2 and r2 represent the content of structural units derived from olefin (1a) and olefin (4a), respectively, and 0 <p2<1かつ0<r2<1かつp2+r2≦1である。) It is preferable that the copolymer contains a structural unit represented by the following formula:

[0027] R in general formulas (4a), (4) and (5) 8 is preferably a hydrogen atom from the viewpoint of improving the MPF reduction ability, and from the same viewpoint, R 9 is preferably a sodium ion.

[0028] From the viewpoint of improving the MPF reduction ability, p2 in general formula (5) is preferably 0.05 or more, more preferably 0.1 or more, and even more preferably 0.15 or more, and from the viewpoint of economic efficiency, it is preferably 0.8 or less, more preferably 0.6 or less, and even more preferably 0.4 or less. Furthermore, from the viewpoint of improving the MPF reduction ability, r2 in general formula (5) is preferably 0.2 or more, more preferably 0.4 or more, and even more preferably 0.6 or more, and from the same viewpoint, it is preferably 0.9 or less, more preferably 0.8 or less, and even more preferably 0.7 or less.

[0029] The copolymerization of the olefin (1a) and the olefin (4a) may be carried out under ordinary copolymerization conditions, and may be, for example, any of alternating copolymerization, block copolymerization, random copolymerization, and the like.

[0030] Furthermore, from the viewpoint of improving the MPF reduction ability, the cationic polymer in the present invention is a polymer having the general formula (6) obtained by mixing and copolymerizing (1a), (2a), and (4a) [ka] (In the formula, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , X, m and Z - p3, q3, and r3 represent the content of structural units derived from olefin (1a), olefin (2a), and olefin (4a), respectively, and 0 <p3<1かつ0<q3<1かつ0<r3<1かつp3+q3+r3≦1である。) The cationic polymer may be represented by the formula:

[0031] In general formula (6), p3 is preferably 0.05 or more, more preferably 0.1 or more, and even more preferably 0.15 or more from the viewpoint of improving MPF reduction ability, and is preferably 0.8 or less, more preferably 0.6 or less, and even more preferably 0.4 or less from the viewpoint of economy. Also, q3 is preferably 0.05 or more, more preferably 0.1 or more, and even more preferably 0.15 or more from the same viewpoint, and is preferably 0.5 or less, more preferably 0.4 or less, and even more preferably 0.3 or less from the same viewpoint. Also, r3 is preferably 0.1 or more, more preferably 0.15 or more, and even more preferably 0.2 or more from the same viewpoint, and is preferably 0.6 or less, more preferably 0.5 or less, and even more preferably 0.4 or less from the same viewpoint.

[0032] In addition, in the cationic polymers represented by the general formulas (5) and (6), a part of the constitutional units derived from the olefin (4a) is replaced with a part of the constitutional units derived from the olefin (4a) represented by the general formula (7), from the viewpoint of improving the MPF reduction ability. [ka] (In the formula, X 1 and X 2 each independently represents -O- or -NH-; m1 represents an integer of 1 or more and 4 or less; s1 represents a number of 1 or more and 30 or less; R 8 This shows the same content as above.) It may also contain a structure in which the hydroxyl group is replaced by a crosslinking structural unit represented by the following formula:

[0033] The crosslinking structural unit represented by general formula (7) is a crosslinking structural unit represented by general formula (7a) together with olefin (1a) (and olefin (4a)) when obtaining a cationic polymer having a structure represented by general formula (5) or (6). [ka] (In the formula, R 8 , X 1 , X 2 , m1 and s1 each have the same meaning as above.) or by copolymerizing diolefin (7a) together with olefin (1a) and olefin (2a) (and olefin (4a)).

[0034] The crosslinking structural unit represented by general formula (7) can be prepared by reacting a polymer having a structure represented by general formula (5) or (6) with a polymer having a structure represented by general formula (8) [ka] (In the formula, X 1 , X 2 , m1, and s1 each have the same meaning as above.) The crosslinking agent can be used to introduce the compound.

[0035] The crosslinking structural unit represented by general formula (7) is preferably introduced into a cationic polymer having a structure represented by (5) or (6) by copolymerizing diolefin (7a) together with olefin (1a) (and olefin (4a)) or by copolymerizing diolefin (8a) together with olefin (1a) and olefin (2a) (and (4a)), in view of high crosslinking efficiency.

[0036] The crosslinked structure of the cationic polymer may be a crosslinked structure obtained by copolymerizing a diolefin such as isoprene, norbornadiene, or divinylbenzene in addition to the diolefin (7a).

[0037] When the cationic polymers represented by general formulas (5) and (6) contain a crosslinked structure represented by general formula (7), the content of the crosslinked structure represented by general formula (8) in the cationic polymer (hereinafter sometimes referred to as r4) is greater than 0 and less than or equal to r2 and less than or equal to r3, respectively.

[0038] X in general formula (8) 1 In the case of -NH-, the R of the structural unit derived from olefin (4a) 9 By replacing X with a hydrogen atom, crosslinking can be achieved by dehydration condensation to form an acid amide bond. 1 In the case of -O-, R of the structural unit derived from olefin (4a) 9 By changing X to a hydrogen atom, cross-linking by an ester bond can be achieved by dehydration condensation. 1 is preferably —O—.

[0039] X in general formulas (7) and (8) 2 is preferably -O- from the viewpoint of improving the MPF reducing ability. From the same viewpoint, m1 is preferably 2 or 3, and more preferably 2. From the viewpoint of improving the MPF reducing ability, s1 is preferably 1 or more, more preferably 3 or more, and even more preferably 10 or more, and from the same viewpoint, is preferably 30 or less, more preferably 25 or less, and even more preferably 20 or less.

[0040] The content of the crosslinking structural unit represented by general formula (7) in the cationic polymer is the mole ratio of the number of crosslinking structural units represented by general formula (7) to the number of all structural units in the cationic polymer, and ([number of moles of crosslinking structural units] / [total number of moles of all structural units]) × 100 (%) is, from the viewpoint of improving the MPF reduction ability, preferably 0.00001% or more, more preferably 0.0001% or more, even more preferably 0.005% or more, and even more preferably 0.003% or more, and from the same viewpoint, is preferably 0.04% or less, more preferably 0.02% or less, even more preferably 0.01% or less, and even more preferably 0.004% or less.

[0041] The ratio of r4 to r2 ([r4 / r2] × 100(%)) and the ratio of r4 to r3 ([r4 / r3] × 100(%)) are each referred to as the crosslinking rate of the structural unit derived from olefin (4a). From the viewpoint of improving the MPF reduction ability, this crosslinking rate is preferably 80% or more, more preferably 85% or more, and even more preferably 90% or more, and from the same viewpoint, it is preferably 100% or less, more preferably 97% or less, and even more preferably 95% or less.

[0042] In addition, the cationic polymer represented by the general formula (5) or (6) may be a polymer in which a part of the structural units derived from the olefin (1a) is replaced with a structural unit derived from the olefin (1b) [ka] (In the formula, R 1 , R 2 , R 3 , X and m are the same as those defined above.) When the structural unit derived from the olefin (1b) is replaced with a structural unit derived from the olefin (4a), the structural unit derived from the olefin (1b) undergoes dehydration condensation with the structural unit derived from the olefin (4a) to form an amide bond and crosslink the structural unit, and a compound represented by the general formula (9) [ka] (In the formula, R 1 , R8 , X 1 , R 2 and m have the same meanings as above.) The crosslinked structural unit may also be represented by the following formula:

[0043] The content of the crosslinking structural unit represented by general formula (9) in the cationic polymer (hereinafter, sometimes referred to as p4) is greater than 0 and less than the aforementioned p2 and p3, respectively.

[0044] The content of the crosslinking structural unit represented by general formula (9) in the cationic polymer is the mole ratio of the number of crosslinking structural units represented by general formula (9) to the number of all structural units in the cationic polymer, and ([number of moles of crosslinking structural units] / [total number of moles of all structural units]) × 100 (%) is, from the viewpoint of improving the MPF reduction ability, preferably 0.00001% or more, more preferably 0.0001% or more, even more preferably 0.0005% or more, still more preferably 0.003% or more, and from the same viewpoint, preferably 0.04% or less, more preferably 0.02% or less, even more preferably 0.01% or less, still more preferably 0.004% or less.

[0045] From the viewpoint of improving the MPF reduction ability, the crosslinking rate of the structural units derived from olefin (1a), expressed as [p4 / p2] × 100(%) or [p4 / p3] × 100(%), is preferably 80% or more, more preferably 85% or more, even more preferably 90% or more, and is preferably 100% or less, more preferably 97% or less, even more preferably 95% or less.

[0046] In addition to the structural units represented by general formula (1), (3), (5), (6), (8), or (9), the cationic polymer of the present invention may contain structural units derived from (meth)acrylic acid, alkyl esters of (meth)acrylic acid having 1 to 4 carbon atoms, 2-hydroxyethyl esters of (meth)acrylic acid, (meth)acrylic acid amide, styrene, vinyl sulfonic acid (salts), vinylbenzene sulfonic acid (salts), (meth)acrylic acid ester alkyl sulfonic acid (salts), (meth)acrylamide alkyl sulfonic acid (salts), etc. From the viewpoint of improving the MPF reduction ability, the content of structural units other than those represented by general formula (1), (3), (5), (6), (8), or (9) in the cationic polymer is preferably 10% or less, more preferably 5% or less, and even more preferably 0%.

[0047] The cationic polymer may be either a polymer consisting of a structural unit represented by general formula (1), (3), (5), (6), (8) or (9), or a polymer containing a structural unit such as the above-mentioned (meth)acrylic acid in addition to these structural units. However, from the viewpoint of improving the MPF reduction ability, the cationic polymer is preferably a polymer consisting of a structural unit represented by general formula (3) or (5) as a structural unit.

[0048] <Anionic surfactants> The MPF reducer of the present invention can further improve the MPF reduction ability of component (a) by using component (b), an anionic surfactant, in combination with component (a), a cationic polymer. Generally, anionic surfactants have the effect of, for example, detaching contaminants such as organic matter adhering to fibers from the fibers and discharging them into water. However, the present invention is characterized in that, when used in combination with component (a), it can suppress the generation of MPF from synthetic fibers and the discharge of MPF into water in fibers, including synthetic fibers. While the mechanism of action is not necessarily limited, it is believed that the adhesion of a complex composed of components (a) and (b) to fibers, including synthetic fibers, suppresses the discharge of MPF from synthetic fibers. In this regard, an anionic surfactant is selected as the compound because it has a hydrophobic portion that can form a complex with component (a) to suppress MPF from synthetic fibers, and an anionic group that easily interacts with the cationic charge of component (a).

[0049] From the viewpoint of further improving the MPF reduction ability of component (a), component (b) is preferably one or more anionic surfactants selected from alkylarylsulfonic acid surfactants, sulfate ester surfactants, alkanesulfonic acid surfactants, olefinsulfonic acid surfactants, alkyl sulfosuccinate ester surfactants, and sulfofatty acid ester surfactants.

[0050] Examples of alkylarylsulfonic acid surfactants include alkylbenzenesulfonates. Specifically, from the viewpoint of further improving the MPF reduction ability of component (a), alkylbenzenesulfonates having an alkyl group preferably having 6 or more carbon atoms, more preferably 8 or more carbon atoms, and from the same viewpoint, preferably 18 or less, more preferably 15 or less carbon atoms. The carbon atom of the alkyl group bonded to the carbon atom of the benzene ring of the alkylbenzenesulfonate may be a secondary carbon atom.

[0051] Examples of sulfate ester surfactants include anionic surfactants having a hydrocarbon group having from 8 to 20 carbon atoms and a sulfate ester group. From the viewpoint of further improving the MPF reduction ability of component (a), the hydrocarbon group preferably has 8 or more carbon atoms, more preferably 10 or more, and even more preferably 12 or more carbon atoms, and from the same viewpoint, preferably 20 or less, more preferably 18 or less, even more preferably 14 or less, and even more preferably 12 or less. The hydrocarbon group is preferably an alkyl group. Examples of sulfate surfactants include alkyl sulfates and polyoxyalkylene alkyl ether sulfates.

[0052] As the alkyl sulfate ester salt, from the viewpoint of further improving the MPF reducing ability of component (a), the number of carbon atoms is preferably 8 or more, more preferably 10 or more, and from the same viewpoint, alkyl groups having preferably 20 or less, more preferably 18 or less, even more preferably 14 or less, and even more preferably 12 or less, and further alkyl groups having straight-chain or branched chains are suitable.

[0053] The polyoxyalkylene alkyl ether sulfate salt is preferably a polyoxyalkylene alkyl ether sulfate salt having an alkyl group having preferably 20 or less, more preferably 18 or less, even more preferably 14 or less, and even more preferably 12 or less carbon atoms, from the viewpoint of further improving the MPF reduction ability of component (a), and further having a linear or branched alkyl group, and the average number of added moles of oxyalkylene groups having from 2 to 3 carbon atoms is preferably 0.5 or more, more preferably 0.7 or more, even more preferably 1.0 or more, and further from the viewpoint of further improving the MPF reduction ability, is preferably 10 or less, more preferably 8 or less, and even more preferably 7 or less. The oxyalkylene group is preferably an oxyalkylene group having from 2 to 4 carbon atoms, and more preferably an oxyalkylene group having from 2 to 3 carbon atoms. Specific examples of the oxyalkylene group having from 2 to 4 carbon atoms include an oxyethylene group, an oxypropylene group, and an oxybutylene group. From the viewpoint of further improving the MPF reduction ability, the oxyalkylene group is preferably at least one selected from an oxyethylene group and an oxypropylene group. The polyoxyalkylene group may be a polyoxyalkylene group consisting of a single type of oxyalkylene group or a polyoxyalkylene group consisting of multiple types of oxyalkylene groups. As a polyoxyethylene group consisting of multiple types of oxyethylene groups, a polyoxyalkylene group containing an oxyethylene group and an oxypropylene group is preferred from the viewpoint of further improving the MPF reduction ability. In the present invention, "containing an oxyethylene group and an oxypropylene group" means that the polyoxyethylene group is obtained by adding an oxyethylene group and an oxypropylene group to a raw material alkyl alcohol. From the viewpoint of further improving the MPF reduction ability, the ratio of the average number of moles of oxyethylene groups added (m1) to the average number of moles of oxypropylene groups added (m2), m1 / m2, is preferably 0.1 or more, more preferably 0.2, from the viewpoint of further improving the MPF reduction ability, and from the same viewpoint, is preferably 10 or less, more preferably 8 or less. When oxyethylene groups and oxypropylene groups are contained, the respective groups may be added randomly or in blocks, and from the viewpoint of further improving the MPF reduction ability, it is preferably added in blocks.

[0054] From the viewpoint of further improving the MPF reducing ability of component (a), the alkane sulfonate surfactant may be an alkane sulfonate having an alkane moiety with preferably 8 or more carbon atoms, more preferably 10 or more carbon atoms, and even more preferably 14 or more carbon atoms, and from the same viewpoint, preferably 20 or less carbon atoms, more preferably 18 or less carbon atoms. From the viewpoint of further improving the MPF reducing ability, secondary alkane sulfonates are preferred.

[0055] Examples of olefin sulfonic acid surfactants include α-olefin sulfonates and internal olefin sulfonates. From the viewpoint of further improving the MPF reduction ability of component (a), the α-olefin sulfonates have an olefin moiety with preferably 8 or more carbon atoms, more preferably 10 or more, and even more preferably 14 or more carbon atoms, and from the same viewpoint, preferably 22 or less, more preferably 20 or less, even more preferably 18 or less, and still more preferably 16 or less carbon atoms. Furthermore, the internal olefin sulfonates have an olefin moiety with preferably 8 or more carbon atoms, more preferably 12 or more, and even more preferably 16 or more carbon atoms, and from the same viewpoint, preferably 24 or less, more preferably 20 or less, and even more preferably 18 or less carbon atoms. From the viewpoint of further improving the MPF reduction ability of component (a), internal olefin sulfonates with a carbon number of 16 are preferred.

[0056] From the viewpoint of further improving the MPF reducing ability of component (a), the sulfosuccinate alkyl ester surfactant is a monoester and / or diester, preferably a diester, of sulfosuccinic acid with a fatty alcohol having a carbon number of preferably 5 or more, more preferably 6 or more, even more preferably 7 or more, and still more preferably 8 or more, and from the same viewpoint, preferably 18 or less, more preferably 14 or less, and even more preferably 10 or less. Also, from the viewpoint of further improving the MPF reducing ability of component (a), a branched alcohol is suitable as the fatty alcohol.

[0057] Examples of sulfofatty acid ester surfactants include α-sulfofatty acid salts in which the fatty acid moiety has 10 to 18 carbon atoms, and α-sulfofatty acid lower alkyl ester salts in which the fatty acid moiety has 10 to 18 carbon atoms and the ester moiety has 1 to 5 carbon atoms.

[0058] Examples of salts of component (b) include alkali metal salts such as sodium salts and potassium salts, alkaline earth metal salts such as magnesium salts, ammonium salts, and organic amine salts such as monoethanolamine salts, diethanolamine salts, and triethanolamine salts.

[0059] The MPF reducer of the present invention may be prepared by mixing the above-described components (a) and (b), but is not limited to this embodiment. An embodiment in which the components (a) and (b) are separately blended and contained in a fiber treatment composition (described below), and the components (a) and (b) coexist in the fiber product treatment composition, is also referred to as an MPF ​​reducer. The MPF reducer of the present invention may also be an MPF ​​reducer having MPF reduction ability. Having MPF reduction ability means that the MPF release rate is less than 100% in the examples of the present application. A higher MPF reduction ability means that the MPF release rate is lower. The preferred MPF release rate is preferably 90% or less, more preferably 80% or less, even more preferably 70% or less, even more preferably 60% or less, even more preferably 50% or less, even more preferably 40% or less, and even more preferably 30% or less, with lower values ​​being even more preferred.

[0060] Furthermore, the mass ratio of the content of component (a) to the content of component (b) in the MPF reducer for fibers of the present invention, [(a) / (b)], is preferably 0.01 or more, more preferably 0.05 or more, and even more preferably 0.1 or more, from the viewpoint of improving the MPF reduction ability, and from the same viewpoint, is preferably 5 or less, more preferably 2 or less, and even more preferably 0.5 or less.

[0061] <Fiber treatment composition> The fiber treatment composition of the present invention contains the above-mentioned fiber MPF reducer. The fiber treatment composition of the present invention may be for reducing MPF.

[0062] From the viewpoint of ease of handling, the fiber treatment composition of the present invention preferably contains a solvent, and particularly preferably water. The water is preferably water that does not contain impurities and is appropriately purified. The water may be well water or industrial water, and from the viewpoint of improving the MPF reduction ability, tap water, purified water, or ion-exchanged water is preferred. Water can be the balance other than the MPF reducer for fibers consisting of component (a) and component (b), and the optional components described below. The fiber treatment composition of the present invention contains water in an amount of preferably 10% by mass or more, more preferably 20% by mass or more, and even more preferably 30% by mass or more, from the viewpoint of stability of a composition containing the MPF reducer for fibers of the present invention and optional components described below, and from the same viewpoint, preferably 90% by mass or less, more preferably 85% by mass or less, and even more preferably 80% by mass or less.

[0063] When the fiber treatment composition of the present invention contains a solvent, preferably water, the content of the fiber MPF reducer in the fiber treatment composition is, from the viewpoint of improving MPF reduction ability, preferably 0.00001% by mass or more, more preferably 0.00003% by mass or more, even more preferably 0.00005% by mass or more, still more preferably 0.001% by mass or more, still more preferably 0.01% by mass or more, still more preferably 0.1% by mass or more, and still more preferably 0.5% by mass or more, and from the viewpoint of appropriate fluidity of the fiber treatment composition, preferably 90% by mass or less, more preferably 80% by mass or less, even more preferably 60% by mass or less, still more preferably 50% by mass or less, still more preferably 40% by mass or less, still more preferably 30% by mass or less, more preferably 10% by mass or less, and still more preferably 5% by mass or less.

[0064] When the fiber treatment composition of the present invention is a fiber treatment composition (1) to be mixed with a solvent, preferably water, to be diluted, and then contacted with fibers for use, the content of the fiber MPF reducer in the fiber treatment composition (1) is, from the viewpoint of improving the MPF reduction ability, preferably 1% by mass or more, more preferably 5% by mass or more, even more preferably 10% by mass or more, and still more preferably 15% by mass or more, and, from the viewpoint of appropriate fluidity of the fiber treatment composition, preferably 90% by mass or less, more preferably 80% by mass or less, even more preferably 60% by mass or less, still more preferably 50% by mass or less, still more preferably 40% by mass or less, still more preferably 30% by mass or less, and still more preferably 20% by mass or less.

[0065] When the fiber treatment composition of the present invention is a fiber treatment composition (2) that contains a solvent, preferably water, and is to be used by contacting fibers as is, the content of the fiber MPF reducer in the fiber treatment composition (2) is, from the viewpoint of improving the MPF reduction ability, preferably at least 0.00001% by mass, more preferably at least 0.00003% by mass, even more preferably at least 0.00005% by mass, still more preferably at least 0.001% by mass, still more preferably at least 0.01% by mass, still more preferably at least 0.1% by mass, and still more preferably at least 0.5% by mass; and, from the viewpoint of ensuring uniform contact with fibers, preferably at most 20% by mass, more preferably at most 10% by mass, even more preferably at most 5% by mass, still more preferably at most 3% by mass, still more preferably at most 1% by mass, still more preferably at most 0.1% by mass, still more preferably at most 0.07% by mass, still more preferably at most 0.05% by mass, and still more preferably at most 0.02% by mass. The fiber treatment composition (2) may be a fiber treatment composition obtained by diluting the above-mentioned fiber treatment composition (1) with water.

[0066] When the fiber treatment composition of the present invention contains water, the pH of the fiber treatment composition at 25°C, measured by the method described below, is preferably 4 or more, more preferably 5 or more, from the viewpoint of improving the MPF reduction ability, and from the same viewpoint, is preferably 12 or less, more preferably 11 or less. [pH measurement method] A pH measurement composite electrode (HORIBA glass ground sleeve type) is connected to a pH meter (HORIBA pH / ion meter F-23) and powered on. A saturated potassium chloride aqueous solution (3.33 mol / L) is used as the pH electrode internal solution. Next, a pH 4.01 standard solution (phthalate standard solution), a pH 6.86 standard solution (neutral phosphate standard solution), and a pH 9.18 standard solution (borate standard solution) are each filled into 100 mL beakers and immersed in a thermostatic bath at 25°C for 30 minutes. The pH measurement electrode is immersed in the thermostatically adjusted pH 6.86 standard solution for 3 minutes, followed by the pH 9.18 standard solution and the pH 4.01 standard solution for 3 minutes each, for calibration. The sample to be measured (the fiber treatment composition of the present invention when it contains water) is then adjusted to 25°C, and the pH meter electrode is immersed in the sample. The pH is measured after 1 minute.

[0067] The viscosity of the fiber treatment composition of the present invention at 25°C is preferably 15 mPa·s or less, more preferably 10 mPa·s or less, and even more preferably 5 mPa·s or less, from the viewpoint of good sprayability using a container equipped with a sprayer, and from the same viewpoint, is preferably 1.0 mPa·s or more, more preferably 1.5 mPa·s or more, and even more preferably 2.0 mPa·s or more. The viscosity of the fiber treatment composition was measured by attaching a No. 1 rotor to a B-type viscometer (model BM) manufactured by Tokyo Keiki Inc., filling the fiber treatment composition into a 200 mL tall glass beaker, adjusting the temperature to 25±0.3°C in a water bath, setting the rotor rotation speed to 60 rpm, and measuring the indicated value 60 seconds after the start of the measurement. The viscosity of the fiber treatment composition can be adjusted by adjusting the content of the fiber MPF reducer.

[0068] <Additional Optional Ingredients> The fiber treatment composition of the present invention may further contain, as optional components, components known to be used in detergents, fabric softeners, etc., such as the following components (1) to (12), within a range that does not affect the effects of the present invention.

[0069] (1) pH adjuster An acidic or alkaline agent may be contained as a pH adjuster. The acid agent may be one or more selected from organic acids and inorganic acids. From the viewpoint of low residue on fibers, the organic acid may be one or more selected from citric acid, malic acid, acetic acid, succinic acid, tartaric acid, fumaric acid, lactic acid, propionic acid, oxalic acid, glutaric acid, adipic acid, gallic acid, mellitic acid, cinnamic acid, salicylic acid, phthalic acid, benzoic acid, pyruvic acid, oxaloacetic acid, and aconitic acid. The inorganic acid may be one or more selected from hydrochloric acid, phosphoric acid, sulfuric acid, boric acid, and carbonic acid. Examples of alkaline agents include inorganic alkaline agents such as alkali metal hydroxides and alkali metal carbonates, and alkanolamines in which one to three of the groups bonded to the nitrogen atom are alkanol groups having from 2 to 4 carbon atoms, and the remaining groups are alkyl groups having from 1 to 4 carbon atoms or hydrogen atoms. Of these, the alkanol group is preferably a hydroxyalkyl group, and more preferably a hydroxyethyl group. Other than the alkanol group, a hydrogen atom or a methyl group is preferred, with a hydrogen atom being particularly preferred. Examples of alkanolamines include alkanolamines such as 2-aminoethanol, N-methylethanolamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, diethanolamine, N-methyldiethanolamine, and triethanolamine.

[0070] (2) Chelating agents Specific examples of chelating agents include aminopolyacetic acids such as ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, and hydroxyethyliminodiacetic acid, or salts thereof; organic acids such as citric acid, lactic acid, tartaric acid, and malic acid, or salts thereof; 1-hydroxyethylidene-1,1-diphosphonic acid, diethylenetriaminepenta(methylenephosphonic acid), and alkali metal or lower amine salts thereof.

[0071] (3) Anti-redeposition agents and / or polymeric dispersants From the viewpoint of low residue on fibers, examples of the anti-redeposition agent and / or polymer-based dispersant include polyacrylic acid, polymaleic acid, carboxymethyl cellulose, and the like.

[0072] (4) Bleach From the viewpoint of low residue on fibers, examples of bleaching agents include hydrogen peroxide, sodium percarbonate, and sodium perborate.

[0073] (5) Bleach activator Examples of bleach activators include tetraacetylethylenediamine and bleach activators represented by formulas (I-2) to (I-7) of JP-A-6-316700.

[0074] (6) Enzymes From the viewpoint of low residue on fibers, the enzyme may be one or more enzymes selected from amylase, sucrase, maltase, lactase, pullulanase, fructofuranosidase, cellulase, protease, and lipase.

[0075] (7) Fluorescent dyes Examples of the fluorescent dye include fluorescent dyes commercially available under the trade names of Tinopal CBS (trade name, manufactured by Ciba Specialty Chemicals) and Whitex SA (trade name, manufactured by Sumitomo Chemical Co., Ltd.).

[0076] (8) Antioxidants Antioxidants include known antioxidant compounds such as 3,5-bis(1,1-dimethylethyl)-4-hydroxy-benzenepropanoic acid, methyl ester (commercially available under the trade name RALOX® 35 from Raschig USA, Arlington, Texas, United States), butylhydroxytoluene (common name: BHT), butylhydroxyanisole (common name: BHA), distyrenated cresol, ascorbic acid (common name: vitamin C), tocopherol (common name: vitamin E), coffee bean extract (chlorogenic acid), and green tea extract (catechin), or known inorganic salts such as sodium sulfite and sodium bisulfite.

[0077] (9) Antifoaming agents such as pigments, antibacterial preservatives, UV inhibitors, and silicones

[0078] (10) Organic solvents containing hydroxyl groups As the organic solvent having a hydroxyl group, one or more compounds selected from the following components (10-1) to (10-6) are used.

[0079] Component (10-1): A monohydric alcohol having an aliphatic hydrocarbon group with 2 to 6 carbon atoms Examples of the component (10-1) include monohydric alcohols selected from ethanol, 1-propanol, 2-propanol, and 1-butanol.

[0080] (10-2) Component: Dihydric to hexahydric alcohol having 2 to 6 carbon atoms Examples of the component (10-2) include dihydric or trihydric alcohols selected from ethylene glycol, propylene glycol, butylene glycol, 2-methyl-2,4-pentanediol, 1,5-pentanediol, 1,6-hexanediol, and glycerin. 2-Methyl-2,4-pentanediol is also known as hexylene glycol.

[0081] Component (10-3): Polyalkylene glycol containing alkylene glycol units having 2 to 4 carbon atoms Examples of the component (10-3) include polyalkylene glycols selected from diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, polyethylene glycols having a weight-average molecular weight of 400 to 4,000, and polypropylene glycols having a weight-average molecular weight of 400 to 4,000.

[0082] Component (10-4): a monoalkyl ether of (mono- or poly) alkylene glycol having an alkylene glycol unit having from 2 to 4 carbon atoms and an alkyl group having from 1 to 4 carbon atoms Examples of the component (10-4) include compounds selected from diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, diethylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, diethylene glycol monobutyl ether, 1-methoxy-2-propanol, and 1-ethoxy-2-propanol.

[0083] Component (10-5): Alkyl glyceryl ether having an alkyl group with 1 to 8 carbon atoms Examples of the component (10-5) include alkyl glyceryl ethers selected from 1-methyl glyceryl ether, 2-methyl glyceryl ether, 1,3-dimethyl glyceryl ether, 1-ethyl glyceryl ether, 1,3-diethyl glyceryl ether, triethyl glyceryl ether, 1-pentyl glyceryl ether, 2-pentyl glyceryl ether, 1-octyl glyceryl ether, and 2-ethylhexyl glyceryl ether.

[0084] (10-6) Component: Aromatic alkyl ether of (mono- or poly-) alkylene glycol having an alkylene glycol unit having 2 or 3 carbon atoms Examples of the component (10-6) include compounds selected from 2-phenoxyethanol, diethylene glycol monophenyl ether, triethylene glycol monophenyl ether, polyethylene glycol monophenyl ether having an average molecular weight of about 480, 2-benzyloxyethanol, and diethylene glycol monobenzyl ether.

[0085] In the above components (10-4) and (10-6), the term "(mono- or poly)alkylene glycol" refers to a monoalkylene glycol or a polyalkylene glycol. Furthermore, "polyalkylene glycol" refers to a glycol containing 2 to 9 alkylene glycol units.

[0086] (11) Hydrotropes The hydrotropic agent is an organic compound having an anionic group, and examples thereof include alkylbenzenecarboxylic acids or alkylbenzenesulfonic acids or salts thereof containing one or two alkyl groups selected from methyl, ethyl, and propyl and one sulfonic or carboxylic acid group, as well as benzoic acid or its salts. More specifically, examples include paratoluenesulfonic acid, cumenesulfonic acid, metaxylenesulfonic acid, and benzoic acid, and the salts are preferably alkali metal salts.

[0087] (12)Fragrance The perfume has a masking effect and in some cases may be a base material that itself has deodorizing properties. As the fragrance, for example, the fragrances described in "Fundamentals of Fragrance and Fragrance Blending, edited by Nakajima Mototaka, published by Sangyo Tosho Co., Ltd., 4th printing, April 20, 2005" and the fragrances described in JP-A-10-507793 can be used. In addition, the fragrance technology described in JP-A-2014-213072 can be used, and silicate ester fragrances and microcapsule fragrances can also be used.

[0088] <Fiber> The fibers to be treated with the MPF reducing agent for fibers and the fiber treatment composition of the present invention are fibers containing one or more synthetic fibers, and may also contain one or more non-synthetic fibers. The fibers in the present invention may be in the form of threads or test pieces having a predetermined size.

[0089] Examples of synthetic fibers include polyamide fibers (e.g., nylon), polyester fibers (e.g., polyester), polyacrylonitrile fibers (e.g., acrylic), polyvinyl alcohol fibers (e.g., vinylon), polyvinyl chloride fibers (e.g., polyvinyl chloride), polyvinylidene chloride fibers (e.g., vinylidene), polyolefin fibers (e.g., polyethylene, polypropylene), polyurethane fibers (e.g., polyurethane), polyvinyl chloride / polyvinyl alcohol copolymer fibers (e.g., polycrelal), polyalkylene paraoxybenzoate fibers (e.g., benzoate), and polyfluoroethylene fibers (e.g., polytetrafluoroethylene). Other examples include semi-synthetic fibers made by chemically extracting, dissolving, and spinning naturally occurring components, such as protein-based fibers (e.g., milk protein casein fiber, Promix), and cellulose-based fibers (e.g., rayon, Polynosic, cupra, acetate).

[0090] <Textile products> The MPF reducing agent for fibers and the fiber treatment composition of the present invention can also be used to treat textile products. As described above, the textile product in the present invention refers to a product manufactured using fibers. Specifically, it refers to fabrics such as woven fabrics, knitted fabrics, and nonwoven fabrics manufactured using fibers containing one or more synthetic fibers, and products obtained using the same, such as undershirts, T-shirts, dress shirts, blouses, slacks, hats, handkerchiefs, towels, knitwear, socks, underwear, tights, and masks. From the viewpoint of improving the MPF reduction ability, the content of synthetic fibers in the textile product is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 20% by mass or more, still more preferably 30% by mass or more, still more preferably 50% by mass or more, and 100% by mass or less. The content of synthetic fibers in the textile product is even more preferably substantially 100% by mass.

[0091] The MPF reducing agent for fibers of the present invention can be used by being formulated in a detergent composition, a softening agent composition, a treatment agent composition or a spray treatment agent composition. Further, the composition for fiber treatment of the present invention can be used together with those compositions. Further, the MPF reducing agent for fibers of the present invention is used as an active ingredient for reducing the amount of MPF. The present invention can be used as a composition for fiber treatment containing a cationic polymer ((a) component), an anionic surfactant ((b) component), and the above optional components.

[0092] <MPF Reduction Method> The present invention provides an MPF reduction method of bringing a fiber into contact with an MPF reducing agent for fibers composed of a cationic polymer ((a) component) and an anionic surfactant ((b) component), or a composition for fiber treatment containing the MPF reducing agent for fibers.

[0093] In the MPF reduction method of the present invention, for the (a) component, (b) component, and the above optional components, the above-mentioned preferred embodiments described in the composition for fiber treatment of the present invention can be applied. And the ratio of the content of each component is the same as the preferred embodiment described in the composition for fiber treatment of the present invention. Further, examples of the fiber include synthetic fibers contained in the fibers and fiber products described in the MPF reducing agent for fibers and the composition for fiber treatment.

[0094] In the MPF reduction method of the present invention, from the viewpoint of improving the MPF reduction ability, preferably, the fiber is treated with a composition for fiber treatment containing the MPF reducing agent for fibers and water (hereinafter, sometimes referred to as a treatment liquid. The treatment liquid can also be read as the above composition for fiber treatment (2).) to bring the fiber into contact with the MPF reducing agent for fibers. In the MPF reduction method of the present invention, examples of the method of bringing the MPF reducing agent for fibers of the present invention into contact with the fiber include a method of spraying the treatment liquid onto the fiber, a method of applying the treatment liquid to the fiber, and a method of immersing the fiber in the treatment liquid.

[0095] The content of the anionic surfactant as component (b) in the composition used for treatment, for example, the treatment liquid or the textile product treatment composition (2), is preferably 10 ppm or more, more preferably 50 ppm or more, and even more preferably 100 ppm or more, from the viewpoint of improving the MPF reduction ability, and from the same viewpoint, is preferably 1,000 ppm or less, more preferably 700 ppm or less, and even more preferably 500 ppm or less.

[0096] The MPF reduction method of the present invention may be, for example, a method for reducing the amount of MPF generated from synthetic fibers when the fibers are washed. The method of spraying the treatment liquid onto fibers is preferably a method in which the treatment liquid of the present invention is filled into a sprayer-equipped container and sprayed onto fibers to bring the treatment liquid into contact with the fibers. When applying the treatment liquid to fibers, the treatment liquid may be applied directly to the fibers, or may be brought into contact with the fibers by carrying the treatment liquid on an applicator such as a cloth or brush and applying it to the fibers.

[0097] The treatment solution is preferably prepared by diluting the MPF reducer for fibers or the fiber treatment composition of the present invention with water. The specific dilution ratio of the fiber treatment composition of the present invention is preferably 500 times or more, more preferably 800 times or more, from the viewpoint of improving the MPF reduction ability and from the viewpoint of the blend stability of the MPF reducer for fibers or the fiber treatment composition, and from the same viewpoint, is preferably 5,000 times or less, more preferably 3,000 times or less.

[0098] The pH of the treatment solution at 25° C. is preferably 4 or higher, more preferably 5 or higher, from the viewpoint of improving the MPF reduction ability, and from the same viewpoint, is preferably 12 or lower, more preferably 11 or lower. The pH of the treatment liquid at 25° C. can be measured by the same method as the method for measuring the pH of the blended liquid of the present invention. In this case, the blended liquid of the MPF reducer for fibers or the fiber treatment composition is read as the treatment liquid containing the MPF reducer for fibers or the fiber treatment composition, and the pH of the treatment liquid is measured.

[0099] The hardness of the water used in preparing the treatment solution is, from the viewpoint of improving the MPF reduction ability, preferably 2°dH or more, more preferably 3.5°dH or more, even more preferably 5°dH or more, and even more preferably 7°dH or more on the German hardness scale, and from the same viewpoint, preferably 20°dH or less, more preferably 18°dH or less, and even more preferably 15°dH or less.

[0100] Here, German hardness (°dH) in this specification refers to the concentration of calcium and magnesium in water, expressed as a CaCO3 equivalent concentration of 1 mg / L (ppm) = approximately 0.056°dH (1°dH = 17.8 ppm). The calcium and magnesium concentrations for this German hardness are determined by chelate titration using disodium ethylenediaminetetraacetic acid. The specific method for measuring German water hardness in this specification is described below.

[0101] <Method for measuring water hardness in Germany> 〔reagent〕 0.01 mol / L EDTA·2Na solution: 0.01 mol / L aqueous solution of disodium ethylenediaminetetraacetate (titration solution, 0.01 M EDTA-2Na, manufactured by SIGMA-ALDRICH) ·Universal BT indicator (product name: Universal BT, manufactured by Dojindo Kagaku Kenkyusho Co., Ltd.) Ammonia buffer solution for hardness measurement (67.5 g of ammonium chloride dissolved in 570 mL of 28 w / v% ammonia water, and then made up to 1000 mL with ion-exchanged water) [Measurement of hardness] (1) Use a volumetric pipette to collect 20 mL of sample water into a conical beaker. (2) Add 2 mL of ammonia buffer solution for hardness measurement. (3) Add 0.5 mL of Universal BT indicator. After addition, confirm that the solution is reddish purple. (4) While shaking the conical beaker well, add 0.01 mol / L EDTA·2Na solution dropwise from the buret until the sample water turns blue, which is the end point of the titration. (5) The total hardness is calculated using the following formula. Hardness (°dH)=T×0.01×F×56.0774×100 / A T:0.01mol / L Titration amount of EDTA・2Na solution (mL) A: Sample volume (20 mL, volume of sample water) F: Factor of 0.01 mol / L EDTA·2Na solution

[0102] Furthermore, from the viewpoint of improving the MPF reduction ability, the temperature of the treatment liquid when treating the fibers is preferably 5°C or higher, more preferably 10°C or higher, and even more preferably 20°C or higher, and from the same viewpoint, it is preferably 60°C or lower, more preferably 50°C or lower, and even more preferably 40°C or lower.

[0103] In the MPF reduction method for fibers of the present invention, the liquor ratio, which is the ratio of the mass (kg) of the fiber to the amount (L) of the treatment solution, i.e., [amount (L) of treatment solution / mass (kg) of fiber] (hereinafter, this ratio may be referred to as the liquor ratio), is preferably 3 or more, more preferably 10 or more, and even more preferably 12 or more, from the viewpoint of improving the MPF reduction ability, and from the same viewpoint, is preferably 30 or less, more preferably 20 or less, and even more preferably 18 or less.

[0104] In the MPF reduction method of the present invention, the time for treating the fibers is preferably 1 minute or more, more preferably 2 minutes or more, and even more preferably 3 minutes or more, from the viewpoint of improving the MPF reduction ability, and from the same viewpoint, is preferably 5 hours or less, more preferably 3 hours or less, even more preferably 1 hour or less, and even more preferably 30 minutes or less.

[0105] The MPF reduction method of the present invention is also suitable for rotary treatment methods. Rotary treatment methods refer to treatment methods in which fibers or textile products that are not fixed to a rotating device rotate around a rotation axis together with a treatment solution. Rotary treatment methods can be carried out using rotary washing machines. Specific examples of rotary washing machines include top-loading washing machines, two-layer washing machines, drum washing machines, pulsator washing machines or agitator washing machines, small washing machines, and automatic loading washing machines. These rotary washing machines can be commercially available for home or industrial use.

[0106] In the MPF reduction method of the present invention, it is preferable to bring fibers into contact with an MPF ​​reducer composition for fibers containing a cationic polymer (component (a)) and an anionic surfactant (component (b)) or a treatment liquid containing the composition. Furthermore, the MPF reduction method of the present invention may be a method of reducing MPF in which component (a) and component (b) are brought into contact with fibers. [Example]

[0107] <Cationic polymer> The following cationic polymers were used as component (a). Cationic polymers (a-1) to (a-7) are copolymers consisting of structural units of the following general formula (10). The x1, y1, and z1 at the bottom right of the square brackets in each cationic polymer indicate the content ratio (mol parts) of each structural unit. The d of the crosslinked sites is approximately 14, and this value indicates the average number of moles of ethyleneoxy groups in the crosslinked sites. [ka]

[0108] Table 1 shows the values ​​of x1, y1, and z1, the weight average molecular weight (Mw), and the charge density of each cationic polymer. [Table 1]

[0109] Cationic polymers (a-8) to (a-16) are copolymers consisting of structural units of the following general formula (11): x2, y2, and z2 at the bottom right of the square brackets in each cationic polymer indicate the content (parts by mole) of each structural unit. [ka]

[0110] Table 2 shows the values ​​of x2, y2, and z2, the weight average molecular weight (Mw), and the charge density of each cationic polymer. [Table 2]

[0111] The charge density of each cationic polymer was calculated by the method described in

[0013] . The weight average molecular weight of each polymer was calculated in terms of polyethylene glycol by GPC described in

[0017] .

[0112] [Method for producing cationic polymer (a-5)] A method for producing a cationic polymer (a-5) for a representative copolymer will be described below. In a 1 L beaker, 43.03 g of ion-exchanged water, 8.62 g (7.76 g of active ingredient) of MOEDES (dimethylaminoethyl methacrylate quaternized with diethyl sulfate, 90% active ingredient by mass, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 22.24 g of DMAAm (N,N-dimethylacrylamide, manufactured by KJ Chemicals Co., Ltd.), and 0.147 g of V-50 (polymerization initiator, 2,2'-azobis(2-amidinopropane) dihydrochloride, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) were mixed and used as monomer aqueous solution A. In a 5 L glass container, 255.14 g of cyclohexane and 100% ethanol as a dispersant were added. TM 0.30 g of Sugar Ester S-770 (manufactured by Mitsubishi Chemical Corporation) was added and dissolved uniformly over 1 hour at 60° C. After dissolution, the solution was cooled to 30° C. to give dispersant solution B. The monomer aqueous solution A was added to the dispersant solution B, which was then placed in a homomixer (ROBOMICS, manufactured by Tokushu Kika Kogyo Co., Ltd.) and stirred at 9000 rpm for 4 minutes to obtain a monomer dispersion with an average particle size of 5 μm. The entire amount was placed in a 500 mL four-neck flask equipped with a stirrer, thermometer, and condenser. After purging with nitrogen, the pressure was reduced to 47.5 Pa and polymerization was carried out at 52°C for 40 minutes. After further aging at 70°C under atmospheric pressure for 1 hour, a dehydration tube equipped with a condenser was attached, and 41 mL of water was removed from the system over approximately 3 hours. As dehydration progressed, the temperature in the tank rose from 78°C to 81°C.

[0113] [Production method of (a-1)] (a-1) was obtained in the same manner as in the method for producing the cationic polymer (a-5), except that 0.0064 g of polyethylene glycol dimethacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) was further mixed into the aqueous monomer solution A.

[0114] [Method for producing polymer (a-6)] (a-6) was obtained in the same manner as in (a-1) above, except that in the production method of the cationic polymer (a-5), 0.018 g of polyethylene glycol dimethacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) was further mixed into the aqueous monomer solution A.

[0115] <Anionic surfactants> The following anionic surfactants were used as component (b). (b-1): Sodium internal olefin sulfonate having 16 carbon atoms (b-2): Polyoxyalkylene lauryl ether sulfate monoethanolamine salt (a sulfate salt in which an average of 2 moles of oxypropylene groups are added to lauryl alcohol, followed by an average of 2 moles of oxyethylene groups). (b-3): Sodium alkylbenzene sulfonate (the alkyl moiety composition is C10 / C11 / C12 / C13 = 11 / 29 / 34 / 26 (mass ratio)) (b-4): Sodium internal olefin sulfonate having 18 carbon atoms (b-5): Sodium polyoxypropylene alkyl ether sulfate (alkyl group: octyl group / decyl group / dodecyl group = 5 / 5 / 90 (mass ratio), average added mol number of oxypropylene group: 0.6 mol) (b-6): Sodium polyoxyethylene alkyl ether sulfate (alkyl group: lauryl group / myristyl group = 70 / 30 (mass ratio), average added mol number of oxyethylene group: 2 mol) (b-7): Sodium dodecyl sulfate (b-8): Sodium bis(2-propylheptyl) sulfosuccinate

[0116] <Evaluation method for MPF reduction ability> Next, the evaluation method for MPF reduction ability will be described. Using component (a), component (b), and tap water (Wakayama City water, 25 °C), the fiber treatment compositions described in Tables 3 to 5 were prepared. Into a standard bottle (PS-NO.11 manufactured by AS ONE Corporation), 25 mL of the fiber treatment composition was put in total, and two 6 cm × 6 cm polyester cloths (cut from MITSUWA TIGER semi-fitted round neck SS underwear) were placed therein. Then, the standard bottle was capped, and the standard bottle was placed horizontally in a small constant temperature shaking incubator (manufactured by TAITEC Corporation, model number: BR-23FP), and rotated and shaken at 25 °C and 150 rpm for 10 min, which was used as the washing step. Subsequently, only the cloth was taken out and transferred to a standard bottle containing 25 mL of Wakayama City water, and the same shaking operation was performed for 3 minutes as the rinsing step. After each step, only the cloth was removed from the standard bottle, and the remaining washing solution was collected and the MPF discharge amount was quantified by the following MPF counting method. The bath ratio was 25. Also, when changing the bath ratio in the examples, the amount of the fiber treatment composition was changed to adjust the bath ratio. The immersion treatment in Tables 3 to 5 corresponds to the rotary treatment method.

[0117] <Quantification of MPF discharge amount by MPF counting method> (Preparation of measurement sample) The entire amount of wash water obtained in the washing and rinsing processes was poured into a petri dish (As One Corporation Ascept Petri dish (electron beam sterilized), diameter 90 mm, height 20 mm) with the lid removed. The walls of the standard bottle were then rinsed with a small amount of tap water, and the rinse water was then added to the petri dish. Visible coarse fibers and impurities that were clearly not MPFs were manually removed using tweezers. The mixture was then lightly stirred with a dropper or similar to ensure uniformity and prevent overlapping of MPFs. The mixture was then left to stand for approximately 1 minute until the MPFs sank to the bottom of the petri dish, and used as a measurement sample. (scan) The measurement sample was scanned using a home scanner (Seiko Epson Corporation GT-X830). Scanning conditions: "Professional mode", image type: 48-bit color, resolution: 600 dpi, unsharp mask effect: "strong" (Counting by image processing) The image file created in (Scan) was read into Image J, and the number of MPFs was counted after the following image processing steps. Evaluation was performed without adding a polymer, and the calculated MPF emission rate was set to 100%, and the percentage (%) of MPF emission rate for each MPF reducer composition was calculated and used as the MPF emission rate (%). The smaller the MPF emission rate, the higher the MPF reduction ability of the MPF reducer. The following image processing steps were performed automatically by a computer based on pre-stored settings. 1.Image>Type>8Bit 2.Process>Subtract Background...>Roolingball radius:50pixels(Check Light background) 3. Select the area you want to analyze inside the dish in a circular shape and set the threshold to 245 in Image > Adjust > Threshold. 4. Analyze > Analyze Particles, set the size to "3-Infenity" and output the summary. 5.Get the count value of the output Summary The results are shown in Tables 3 to 5.

[0118] Table 3

[0119] Table 4

[0120] Table 5

Claims

1. A microplastic fiber reducing agent for textiles, comprising component (a) and component (b). Component (a): A cationic polymer containing a structural unit represented by the following general formula (1), and optionally one or more structural units selected from a structural unit represented by the following general formula (2) and a structural unit represented by the following general formula (4): 【Chemistry 1】 (In the formula, R １ represents a hydrogen atom or a methyl group. ２ , R ３ and R ４ each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; X represents -O- or -NH-; m represents an integer of 1 to 4; Z － indicates the counter anion.) 【Chemistry 2】 (In the formula, R ５ represents a hydrogen atom or a methyl group. ６ and R ７ each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. 【Transformation 3】 (In the formula, R ８ represents a hydrogen atom or a methyl group. ９ represents a hydrogen ion, an alkali metal ion, a (1 / 2) alkaline earth metal ion, an ammonium ion, or an alkylammonium ion having an alkyl group having 1 to 4 carbon atoms. (b) Anionic surfactants.

2. The microplastic fiber reducing agent for fibers according to claim 1, wherein the cationic polymer contains a crosslinked structural unit represented by general formula (7). 【Chemistry 4】 (In the formula, R ８ indicates the same content as above. １ and X ２ represents —O— or —NH—. m1 represents an integer of 1 or more and 4 or less. s1 represents a number of 1 or more and 30 or less.

3. The microplastic fiber reducing agent for fibers according to claim 2, wherein the content of the number of crosslinking structural units of general formula (7) in the cationic polymer relative to the total number of structural units in the cationic polymer, ([number of moles of crosslinking structural units] / [number of moles of all structural units]) x 100 (%), is 0.05% or less.

4. The microplastic fiber reducing agent for fibers according to claim 1, wherein the weight average molecular weight of the cationic polymer is 1,000,000 or more.

5. The microplastic fiber reducing agent for fibers according to claim 1, wherein the charge density of the cationic polymer is +0.1 meq / g or more and less than +20 meq / g.

6. The microplastic fiber reducing agent for fibers according to claim 1, wherein component (b) is one or more anionic surfactants selected from alkylarylsulfonic acid surfactants, sulfate ester surfactants, alkanesulfonic acid surfactants, olefinsulfonic acid surfactants, sulfosuccinic acid alkyl ester surfactants, and sulfofatty acid ester surfactants.

7. The microplastic fiber reducing agent for fibers described in claim 1, wherein the mass ratio of the content of component (a) to the content of component (b), [(a) / (b)], is 0.01 or more and 5 or less.

8. A fiber treatment composition containing the microplastic fiber reducing agent for fibers according to claim 1.

9. A method for reducing microplastic fibers, comprising contacting fibers with the microplastic fiber reducing agent for fibers described in claim 1 or a fiber treatment composition containing the microplastic fiber reducing agent for fibers described in claim 8.

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