Liquid detergent composition

Abstract

To provide a liquid detergent composition capable of reducing the use amount of a solubilizing agent not contributing to detergency.SOLUTION: A liquid detergent composition comprising a (poly) alkylene glycol-containing compound and a nonionic surfactant, wherein the (poly) alkylene glycol-containing compound comprises a hydrophobic structural moiety (A), a (poly) alkylene glycol moiety (B), and a carboxylic acid (salt) And a group-containing structural moiety (C), wherein a content ratio of the nonionic surfactant is 0.01 to 20% by mass based on 100% by mass of the composition.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a liquid detergent composition, and more particularly to a liquid detergent composition useful as a liquid detergent for hard surfaces. [Background technology]

[0002] Polyalkylene glycol-based polymers are used in a variety of industrial fields and are also useful in applications such as detergents. For example, Patent Document 1 discloses a cleaning composition containing a polyalkylene glycol-based graft polymer, wherein the polyalkylene glycol-based graft polymer is obtained by polymerizing a polyalkylene glycol-based compound represented by a predetermined formula and a monomer material containing at least one carboxyl group-containing monomer in a polymerization mixture, and the polymerization mixture contains 60% by mass to 95% by mass of the polyalkylene glycol-based compound and 5% by mass to 40% by mass of the at least one carboxyl group-containing monomer, based on the total mass of the polyalkylene glycol-based compound and the monomer material in the polymerization mixture.

[0003] Furthermore, Patent Document 2 discloses a hydrophilic graft polymer obtained by graft polymerizing a monomer component containing an unsaturated monocarboxylic acid onto a polyalkylene oxide, in which the molar ratio of side chain portions derived from the unsaturated monocarboxylic acid exceeds 90 mol% with respect to all side chains, and the amount of remaining unsaturated monocarboxylic acid is less than 200 ppm by mass with respect to the total mass of the hydrophilic graft polymer.

[0004] A spray washer is a cleaning machine that sprays cleaning liquid or the like to remove dirt. The flow of liquid sprayed from the washer generates a certain physical force, which can effectively remove dirt from the object. The cleaning liquid used in the spray cleaner must contain a low-foaming surfactant to prevent a decrease in cleaning power due to foam entrapment. Furthermore, low-foaming cleaners are required for the Clean in Place (CIP) method, which cleans equipment without disassembling it, and for ultrasonic cleaning of metal parts, from the viewpoint of machine operation and rinsing performance. Nonionic surfactants are an example of low-foaming surfactants, but when a nonionic surfactant is used, a large amount of a solubilizer is required in order to enhance compatibility in the composition. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 2014-501819 [Patent Document 2] International Publication No. 2008 / 020556 Summary of the Invention [Problem to be solved by the invention]

[0006] As mentioned above, liquid detergent compositions containing nonionic surfactants require a large amount of solubilizer, but since solubilizers are components that do not usually contribute to cleaning properties, there is a need to reduce the amount of solubilizer that does not contribute to cleaning properties.

[0007] The present invention has been made in view of the above-mentioned current situation, and aims to provide a liquid detergent composition that can reduce the amount of solubilizing agent used, which does not contribute to cleaning properties. [Means for solving the problem]

[0008] The present inventors have conducted extensive research into liquid detergent compositions containing nonionic surfactants and have found that the use of a (poly)alkylene glycol-containing compound having a hydrophobic structural moiety (A), a (poly)alkylene glycol moiety (B), and a carboxylic acid (salt) group-containing structural moiety (C) improves the compatibility of the nonionic surfactant in the composition and enables a reduction in the amount of solubilizer used. This has led to the realization that the above-mentioned problems can be successfully solved, and has led to the present invention.

[0009] The present invention encompasses the following liquid detergent compositions and the like. [1] A liquid detergent composition comprising a (poly)alkylene glycol-containing compound and a nonionic surfactant, wherein the (poly)alkylene glycol-containing compound has a hydrophobic structural moiety (A), a (poly)alkylene glycol moiety (B), and a carboxylic acid (salt) group-containing structural moiety (C), and the content of the nonionic surfactant is 0.01 to 20% by mass relative to 100% by mass of the composition. [2] The liquid detergent composition according to the above [1], wherein the content of the (poly)alkylene glycol-containing compound is 0.01 to 20% by mass relative to 100% by mass of the composition. [3] The liquid detergent composition according to the above [1] or [2], wherein the proportion of the carboxylic acid (salt) group-containing structural moiety (C) in the (poly)alkylene glycol-containing compound is 1 to 50 mass % relative to 100 mass % of the compound. [4] The liquid detergent composition according to any one of [1] to [3] above, wherein the (poly)alkylene glycol-containing compound has a main chain having a hydrophobic structural portion (A) and a (poly)alkylene glycol portion (B), and a side chain formed by graft polymerization of a monomer component containing an unsaturated carboxylic acid monomer onto the main chain. [5] The (poly)alkylene glycol-containing compound is represented by the following formula (1): R 1 -O-(R 2 O) n -R 3 (1) (In the formula, R 1 represents a hydrophobic group.2 O are the same or different and represent an oxyalkylene group having 2 to 18 carbon atoms. n represents the average number of moles of oxyalkylene groups added and is a number from 1 to 500. R 3 represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms. The liquid detergent composition according to any one of [1] to [4] above, wherein the polymer is obtained by graft polymerization of a compound represented by the formula: [6] R in the formula (1) 1 The liquid detergent composition according to [5] above, wherein the hydrophobic group is an organic group having 4 or more carbon atoms. [7] R in the formula (1) 1 The liquid detergent composition according to the above [5] or [6], wherein the hydrophobic group is an alkyl group having 4 or more carbon atoms or an aromatic group having 6 or more carbon atoms. [8] The liquid detergent composition according to any one of the above [1] to [7], further comprising a compound that exhibits neutral to basic properties in an aqueous solution. [9] The liquid detergent composition according to [8] above, wherein the content of the compound that is neutral to basic in an aqueous solution is 1 to 30 mass % relative to 100 mass % of the composition. [Effects of the Invention]

[0010] The liquid detergent composition of the present invention has the above-mentioned configuration and can reduce the amount of solubilizer used, which does not contribute to cleaning properties, so it can be suitably used as a detergent for automatic dishwashers, etc. DETAILED DESCRIPTION OF THE INVENTION

[0011] Preferred embodiments of the present invention will be specifically described below, but the present invention is not limited to the following description and can be appropriately modified and applied within the scope of the present invention. Note that combinations of two or more of the individual preferred embodiments of the present invention described below also fall within the scope of preferred embodiments of the present invention.

[0012] [Liquid detergent composition] The liquid detergent composition of the present invention (hereinafter also referred to simply as the composition) contains a (poly)alkylene glycol-containing compound having a hydrophobic structural portion (A), a (poly)alkylene glycol portion (B), and a carboxylic acid (salt) group-containing structural portion (C). The (poly)alkylene glycol-containing compound enhances the compatibility of the nonionic surfactant in the composition and also contributes to the dispersibility of proteinaceous soils and the like, thereby improving the detergency of the composition.

[0013] The content of the (poly)alkylene glycol-containing compound in the liquid detergent composition is not particularly limited, but is preferably 0.01 to 20% by mass, more preferably 1 to 10% by mass, and even more preferably 3 to 10% by mass, relative to 100% by mass of the composition.

[0014] The liquid detergent composition contains a nonionic surfactant, and the content of the nonionic surfactant in the composition is 0.01 to 20% by mass, relative to 100% by mass of the composition. This more sufficiently suppresses excessive foaming during cleaning, and can sufficiently prevent foam trapping in machines such as spray cleaners. The content of the nonionic surfactant in detergents for spray cleaners is preferably 0.01 to 15% by mass, more preferably 0.01 to 10% by mass, and even more preferably 0.1 to 3% by mass. The content of the nonionic surfactant in detergents for machines other than spray cleaners is preferably 0.01 to 15% by mass, more preferably 0.1 to 10% by mass. The blending ratio of the nonionic surfactant to the (poly)alkylene glycol-containing compound in the liquid detergent composition is not particularly limited, but is preferably 1 / 100 to 10 / 1, more preferably 1 / 50 to 5 / 1, and even more preferably 1 / 10 to 1 / 1.

[0015] The liquid detergent composition preferably contains a compound that exhibits neutral to basic properties in an aqueous solution. This improves the detergency against acidic soiling, such as oily soiling and proteinaceous soiling. By including the (poly)alkylene glycol-containing compound in the composition of the present invention, the compatibility of the nonionic surfactant can be sufficiently enhanced even when the salt concentration of the composition is high. The content of the compound that exhibits neutral to basic properties in the aqueous solution in the composition is not particularly limited, but is preferably 1 to 30% by mass relative to 100% by mass of the composition. If the content is 1% by mass or more, the cleaning properties are further improved, and from an economical standpoint, it is preferably 30% by mass or less. More preferably, it is 5 to 20% by mass.

[0016] The liquid detergent composition may contain a solubilizing agent. The content of the solubilizing agent in the composition is not particularly limited, but is preferably 0.01 to 20% by mass, more preferably 0.01 to 10% by mass, relative to 100% by mass of the composition. A configuration in which the content of the solubilizing agent is 0% by mass is also a preferred embodiment of the present invention.

[0017] The liquid detergent composition may contain other components in addition to the (poly)alkylene glycol-containing compound, nonionic surfactant, compound exhibiting neutral to basic properties in aqueous solution, and solubilizer. The content of the other components in the composition is not particularly limited, but is preferably 0.01 to 60% by mass, more preferably 5 to 50% by mass, based on 100% by mass of the composition. A configuration in which the content of the other components is 0% by mass is also a preferred embodiment of the present invention.

[0018] The liquid detergent composition preferably has a pH of 6 to 14, more preferably 7 to 14, and even more preferably 10 to 14. The pH of the composition can be measured with a pH meter.

[0019] The essential and optional components contained in the liquid detergent composition of the present invention will be further described below.

[0020] <(Poly)alkylene glycol-containing compound> The (poly)alkylene glycol-containing compound (hereinafter also referred to as PAG compound) contained in the liquid detergent composition is a compound having a hydrophobic structural portion (A), a (poly)alkylene glycol portion (B), and a carboxylic acid (salt) group-containing structural portion (C). The hydrophobic structural portion (A) and the (poly)alkylene glycol portion (B) impart compatibility with nonionic surfactants, while the carboxylic acid (salt) group-containing structural portion (C) imparts dispersibility to dirt. Therefore, the PAG compound can reduce the amount of solubilizer used in the composition and still exhibit excellent cleaning performance. Furthermore, the PAG compound exhibits excellent chelating ability to calcium ions, and therefore has excellent anti-scale performance. The PAG compound may have at least one of the structural moiety (A), the structural moiety (B), and the structural moiety (C) in one molecule, and may have a plurality of these moieties.

[0021] The PAG compound may have at least one structural moiety (A), one structural moiety (B), and one structural moiety (C) in any manner. The PAG compound may be, for example, a copolymer of monomer components including a hydrophobic monomer, an unsaturated (poly)alkylene glycol monomer, and an unsaturated carboxylic acid monomer, as described below, and optionally other monomers such as a cationic monomer, or a graft polymer obtained by graft polymerizing a monomer component including an unsaturated carboxylic acid monomer onto a (poly)alkylene glycol having a hydrophobic group at its terminal. The PAG compound is preferably the graft polymer.

[0022] The proportion of the hydrophobic structural moiety (A) in the PAG compound is not particularly limited, but is preferably 1 to 40% by mass relative to 100% by mass of the compound. This further improves compatibility with nonionic surfactants. The proportion of the structural moiety (A) is more preferably 1 to 10% by mass, and even more preferably 1 to 6% by mass. When the PAG compound has a plurality of the structural moieties (A) in one molecule, the above ratio is the total ratio of the structural moieties (A).

[0023] The proportion of the (poly)alkylene glycol moiety (B) in the PAG compound is not particularly limited, but is preferably 1 to 80% by mass relative to 100% by mass of the compound. This further improves compatibility with nonionic surfactants. The proportion of the (poly)alkylene glycol moiety (B) is more preferably 50 to 70% by mass. When the PAG compound has a plurality of the moieties (B) in one molecule, the above ratio is the total ratio of the moieties (B).

[0024] The proportion of the carboxylic acid (salt) group-containing structural moiety (C) in the PAG compound is not particularly limited, but is preferably 1 to 50% by mass relative to 100% by mass of the compound. This further improves the dispersibility of dirt. The proportion of the structural moiety (C) is more preferably 20 to 40% by mass. When the PAG compound has a plurality of the structural moieties (C) in one molecule, the above ratio is the total ratio of the structural moieties (C).

[0025] The PAG compound may have a structure other than the structural moiety (A), the structural moiety (B), and the structural moiety (C), and the proportion thereof is not particularly limited, but is preferably 0 to 50% by mass, more preferably 0 to 10% by mass, relative to 100% by mass of the compound.

[0026] The number average molecular weight of the PAG compound is not particularly limited, but is preferably 1,000 to 1,000,000. The number average molecular weight is more preferably 1,500 to 500,000, and even more preferably 2,000 to 100,000. The number average molecular weight of the PAG compound can be measured by GPC.

[0027] (Hydrophobic structural portion (A)) The hydrophobic structural portion (A) in the PAG compound is preferably a structure derived from a hydrophobic organic compound or a structure derived from a hydrophobic polymerizable unsaturated monomer. The structural moiety (A) derived from an organic compound exhibiting hydrophobicity means a structure obtained by abstracting one or more hydrogen atoms from the organic compound. In the present invention, the term "structural unit derived from a monomer" refers to a structural unit having the same structure as a structural unit formed by polymerization of a monomer. Note that the structural unit having the same structure as a structural unit formed by polymerization of a monomer is not limited to only a structural unit formed by actual polymerization of a monomer, but may also be a structural unit formed by another method as long as it has the same structure as a structural unit formed by polymerization of a monomer.

[0028] The hydrophobic organic compound preferably has an insoluble content of 9.5 g or more when 10 g is dissolved in 100 g of water at 25°C. The organic compound is preferably a hydrocarbon compound having 4 to 50 carbon atoms which may have a heteroatom. The hydrocarbon compound preferably has 5 to 30 carbon atoms, more preferably 6 to 21 carbon atoms, even more preferably 6 to 18 carbon atoms, and particularly preferably 6 to 14 carbon atoms.

[0029] Examples of the hydrocarbon compound include acyclic hydrocarbon compounds, cyclic saturated hydrocarbon compounds, aromatic compounds, etc. As long as the hydrophobic structural moiety in the PAG compound exhibits hydrophobicity, the hydrocarbon compound may contain heteroatoms such as nitrogen atoms, sulfur atoms, oxygen atoms, phosphorus atoms, and halogen atoms, and may also contain substituents such as hydroxyl groups, alkoxy groups, carboxyl groups, acyl groups, sulfonic acid groups, amino groups, and phosphate groups.

[0030] The hydrophobic structural portion (A) in the PAG compound is preferably a structure derived from at least one compound selected from the group consisting of acyclic hydrocarbon compounds having 4 to 50 carbon atoms which may have a heteroatom, cyclic saturated hydrocarbon compounds having 4 to 50 carbon atoms which may have a heteroatom, and aromatic compounds having 6 to 50 carbon atoms which may have a heteroatom.

[0031] Examples of the acyclic hydrocarbon compound include alkanes, alkenes, alkynes, and the like having 4 to 50 carbon atoms. Examples of alkanes having 4 to 50 carbon atoms include linear or branched alkanes such as butane, pentane, hexane, heptane, octane, nonane, decane, undecane, dodecane, tridecane, tetradecane, pentadecane, hexadecane, heptadecane, octadecane, nonadecane, icosane, henicosane, tetracosane, triacontane, tetracontane, and pentacontane.

[0032] Examples of alkenes having 4 to 50 carbon atoms include straight-chain or branched-chain alkenes such as butene, pentene, hexene, heptene, octene, nonene, decene, undecene, dodecene, tridecene, tetradecene, pentadecene, hexadecene, heptadecene, octadecene, nonadecene, icosene, henicosene, tetracosene, triacontene, tetracontene, and pentacontene.

[0033] Examples of alkynes having 4 to 50 carbon atoms include linear or branched alkynes such as butyne, pentyne, hexyne, heptyne, octyne, nonyne, decyne, undecyne, dodecyne, tridecyne, tetradecyne, pentadecyne, hexadecyne, heptadecyne, octadecyne, nonadecyne, icosine, heneicosine, tetracosine, triacontyne, tetracontyne, and pentacontyne.

[0034] Examples of the cyclic saturated hydrocarbon compound having 4 to 50 carbon atoms include cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, and the like, as well as compounds having one or more alkyl groups, alkenyl groups, or the like in these compounds.

[0035] Examples of aromatic compounds having 6 to 50 carbon atoms include benzene, naphthalene, anthracene, phenanthrene, biphenyl, terphenyl, toluene, o-xylene, m-xylene, p-xylene, ot-butyltoluene, mt-butyltoluene, pt-butyltoluene, 1-ethyl-4-methylbenzene, 1-ethyl-3-methylbenzene, 1-isopropyl-4-methylbenzene, 1-t-butyl-4-methylbenzene, mesitylene, pseudocumene, durene, methylnaphthalene, dimethylnaphthalene, 1,2,3,4-tetrahydronaphthalene, methylanthracene, 4,4'-dimethylbiphenyl, ethylbenzene, propylbenzene, butylbenzene, 1,4-diethylbenzene, styrene, distyrenated phenyl, quaterphenyl, quinquephenyl, sexiphenyl, septiphenyl, octiphenyl, and the like, as well as compounds having one or more alkyl groups, alkenyl groups, or the like on an aromatic ring.

[0036] The hydrophobic polymerizable unsaturated monomer (hereinafter also referred to as hydrophobic monomer) is not particularly limited, but is preferably a monomer having an ethylenically unsaturated group and a hydrocarbon group having 1 to 30 carbon atoms. The hydrocarbon group preferably has 2 to 22 carbon atoms, more preferably 3 to 16 carbon atoms, and even more preferably 4 to 8 carbon atoms. Examples of hydrophobic monomers include esters of unsaturated carboxylic acids such as (meth)acrylic acid and alcohols having 2 to 30 carbon atoms which may have a substituent; aromatic vinyl monomers such as styrene; olefin monomers having 5 to 20 carbon atoms such as pentene and hexene; esters of unsaturated alcohols such as vinyl acetate and carboxylic acids having 2 to 8 carbon atoms; alkyl vinyl ethers having an alkyl group having 1 to 20 carbon atoms such as methyl vinyl ether, ethyl vinyl ether, and propyl vinyl ether; and cyclic vinyl monomers such as N-vinylpyrrolidone.

[0037] The substituent that the alcohol may have may be any substituent other than a hydroxyl group, an oxyalkylene group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, a secondary or tertiary amino group, or a salt thereof, and examples thereof include a halogen atom. The alcohol preferably has 2 to 22 carbon atoms, more preferably 3 to 16 carbon atoms, and even more preferably 4 to 8 carbon atoms. Preferred examples of the alcohol having 2 to 30 carbon atoms include alkyl alcohols having 2 to 30 carbon atoms and aromatic alcohols having 6 to 30 carbon atoms.

[0038] Examples of the alkyl alcohol having 2 to 30 carbon atoms include ethanol, propanol, butanol, pentyl alcohol, hexyl alcohol, heptyl alcohol, octyl alcohol, nonyl alcohol, decyl alcohol, undecyl alcohol, dodecyl alcohol (lauryl alcohol), tridecyl alcohol, tetradecyl alcohol, pentadecyl alcohol, hexadecyl alcohol, heptadecyl alcohol, octadecyl alcohol, nonadecyl alcohol, and icosyl alcohol.

[0039] The aromatic alcohol having 6 to 30 carbon atoms is preferably phenol, benzyl alcohol, methylphenyl alcohol (o-cresol, m-cresol, p-cresol), creosol, ethylphenyl alcohol, propylphenyl alcohol, butylphenyl alcohol, butylmethylphenyl alcohol, dimethylphenyl alcohol, diethylphenyl alcohol, dibutylphenyl alcohol, hydroxybiphenyl, 4-hydroxymethylbiphenyl, 3-hydroxymethylbiphenyl, 4-hydroxyethylbiphenyl, 3-hydroxyethylbiphenyl, naphthol, 1-hydroxymethylnaphthalene, 1-hydroxyethylnaphthalene, 2-hydroxymethylnaphthalene, 2 ... Hydroxyethyl-naphthalene and the like.

[0040] The hydrophobic monomer is preferably an alkyl (meth)acrylate or an aromatic (meth)acrylate.

[0041] Examples of the alkyl (meth)acrylate include ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, sec-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, stearyl (meth)acrylate, and icosyl (meth)acrylate. Among these, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, sec-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and n-octyl (meth)acrylate are preferred, and ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, sec-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate are more preferred.

[0042] Examples of the aromatic (meth)acrylate include phenyl (meth)acrylate, benzyl (meth)acrylate, 2-ethylphenyl (meth)acrylate, propylphenyl (meth)acrylate, butylphenyl (meth)acrylate, pentylphenyl (meth)acrylate, hexylphenyl (meth)acrylate, and butylmethylphenyl. (meth)acrylate, dimethylphenyl (meth)acrylate, diethylphenyl (meth)acrylate, dibutylphenyl (meth)acrylate, 2-phenylethyl (meth)acrylate, 4-methylphenyl (meth)acrylate, 4-methylbenzyl (meth)acrylate, 1-methoxy-4-methylphenyl (meth)acrylate, 2-(2-methylphenyl)ethyl (meth)acrylate, 2-(3-methylphenyl)ethyl (meth)acrylate, 2-(4-methylphenyl)ethyl (meth)acrylate, 2-(4-propylphenyl)ethyl (meth)acrylate, biphenylmethyl (meth)acrylate, biphenylethyl (meth)acrylate, naphthyl (meth)acrylate, naphthylmethyl (meth)acrylate, naphthylethyl (meth)acrylate, etc. Among these, phenyl (meth)acrylate and benzyl (meth)acrylate are preferred.

[0043] <(Poly)alkylene glycol moiety (B)> The PAG compound has a (poly)alkylene glycol moiety (B), and the alkylene groups constituting the moiety (B) may be the same or different and preferably have 2 to 20 carbon atoms. The alkylene groups preferably have 2 to 20 carbon atoms, and may be the same or different. This means that when a plurality of alkylene groups are present in the (poly)alkylene glycol, the alkylene groups may all have the same or different carbon atoms.

[0044] The (poly)alkylene glycol moiety (B) in the PAG compound is represented by the following formula (2): -(R 2 O) n - (2) (In the formula, R 2 are the same or different and represent an alkylene group having 2 to 18 carbon atoms. n represents a number from 1 to 500. R 2 are the same or different and represent alkylene groups having 2 to 18 carbon atoms, and n R 2This means that all of the alkylene groups may be the same or different. R 2 The oxyalkylene group represented by O is an alkylene oxide adduct, and examples of such alkylene oxides include alkylene oxides having 2 to 8 carbon atoms such as ethylene oxide, propylene oxide, butylene oxide, isobutylene oxide, 1-butene oxide, 2-butene oxide, and styrene oxide. More preferred are alkylene oxides having 2 to 4 carbon atoms such as ethylene oxide, propylene oxide, and butylene oxide, and even more preferred are ethylene oxide and propylene oxide. Furthermore, when the polyalkylene glycol is an adduct of any two or more alkylene oxides selected from ethylene oxide, propylene oxide, butylene oxide, styrene oxide, etc., it may be in any form of random addition, block addition, alternating addition, etc. In order to ensure a balance between hydrophilicity and hydrophobicity, it is preferable that the oxyalkylene groups in the (poly)alkylene glycol contain oxyethylene groups as an essential component, more preferably 50 mol % or more of oxyethylene groups, and even more preferably 90 mol % or more of oxyethylene groups.

[0045] In the above formula (2), n is the average number of moles of oxyalkylene groups added, and represents a number of 1 to 500. n is preferably 2 to 300, more preferably 3 to 100, even more preferably 4 to 80, still more preferably 5 to 60, particularly preferably 6 to 50, even more preferably 7 to 45, still more preferably 8 to 40, and most preferably 10 to 30.

[0046] The (poly)alkylene glycol moiety (B) may be a moiety derived from an unsaturated (poly)alkylene glycol monomer. Specific examples of the unsaturated (poly)alkylene glycol monomer include polyalkylene glycol (meth)acrylates such as polyethylene glycol (meth)acrylate, and alkoxypolyalkylene glycol (meth)acrylates obtained by hydrophobically modifying the terminals of these with hydrocarbon groups having 1 to 30 carbon atoms; compounds obtained by adding 1 to 500 moles of alkylene oxide to unsaturated alcohols having 2 to 8 carbon atoms such as vinyl alcohol, allyl alcohol, methallyl alcohol, 3-methyl-3-buten-1-ol, 3-methyl-2-buten-1-ol, 2-methyl-3-buten-1-ol, 2-methyl-2-buten-1-ol, and 3-allyloxy-1,2-propanediol, and compounds obtained by hydrophobically modifying the terminals of these with hydrocarbon groups having 1 to 30 carbon atoms. A preferred form of the (poly)alkylene glycol in the unsaturated (poly)alkylene glycol monomer is the structure represented by the above formula (2).

[0047] (Carboxylic acid (salt) group-containing structural portion (C)) The carboxylic acid (salt) group-containing structural moiety (C) is not particularly limited as long as it is a structural moiety having a carboxylic acid (salt) group, but is preferably a structure derived from an unsaturated carboxylic acid monomer.

[0048] The unsaturated carboxylic acid monomer is preferably an unsaturated monocarboxylic acid monomer or an unsaturated dicarboxylic acid monomer. The unsaturated monocarboxylic acid monomer may be any monomer having one unsaturated group and one group capable of forming a carbanion in the molecule. Examples of the unsaturated monocarboxylic acid monomer include (meth)acrylic acid, crotonic acid, tiglic acid, 3-methylcrotonic acid, 2-methyl-2-pentenoic acid, α-hydroxyacrylic acid, α-hydroxymethylacrylic acid, and the like; and monovalent metal salts, divalent metal salts, ammonium salts, and organic amine salts thereof are preferred. The unsaturated dicarboxylic acid monomer may be any monomer having one unsaturated group and two groups capable of forming a carbanion in the molecule, and preferred examples include maleic acid, itaconic acid, mesaconic acid, citraconic acid, fumaric acid, etc., and their monovalent metal salts, divalent metal salts, ammonium salts, and organic amine salts, anhydrides, or half esters. As the unsaturated carboxylic acid monomer, one or more of these can be used. The unsaturated carboxylic acid monomer is preferably an unsaturated monocarboxylic acid monomer, more preferably (meth)acrylic acid or a salt thereof.

[0049] (graft polymer) The PAG compound in the liquid detergent composition of the present invention is preferably a graft polymer having a main chain having a hydrophobic structural portion (A) and a (poly)alkylene glycol portion (B), and a side chain formed by graft polymerization of a monomer component containing an unsaturated carboxylic acid monomer onto the main chain. More preferred is a graft polymer obtained by graft polymerizing a monomer component containing an unsaturated carboxylic acid monomer onto a (poly)alkylene glycol having a hydrophobic group at its terminal. The graft polymer preferably has a main chain consisting of a hydrophobic structural portion (A) and a (poly)alkylene glycol portion (B) represented by the above formula (2), and a side chain formed by graft polymerization of a monomer component containing an unsaturated carboxylic acid monomer.

[0050] The graft polymer is more preferably a polymer represented by the following formula (1): R 1 -O-(R 2 O) n -R 3 (1) (In the formula, R 1 represents a hydrophobic group. 2 O are the same or different and represent an oxyalkylene group having 2 to 18 carbon atoms. n represents the average number of moles of oxyalkylene groups added and is a number from 1 to 500. R 3represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms. The polymer is obtained by graft polymerizing a monomer component containing an unsaturated carboxylic acid monomer onto a compound represented by the formula:

[0051] R in the above formula (1) 2 Preferred embodiments of O and n are as described above in formula (2). Above R 1 is a hydrophobic group, and is preferably a group derived from the above-mentioned organic compound exhibiting hydrophobicity. 1 Specifically, the alkyl group is a hydrocarbon group which may have a hetero atom. Examples of the hydrocarbon group include aromatic groups such as alkyl groups having 4 to 50 carbon atoms, alkenyl groups having 4 to 50 carbon atoms, alkynyl groups having 4 to 50 carbon atoms, aryl groups having 6 to 50 carbon atoms, and aralkyl groups having 6 to 50 carbon atoms. The hydrocarbon group preferably has 5 to 30 carbon atoms, more preferably 6 to 21 carbon atoms, even more preferably 6 to 18 carbon atoms, and particularly preferably 6 to 14 carbon atoms.

[0052] Examples of the alkyl group include an n-butyl group, an n-pentyl group (amyl group), an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, an n-dodecyl group, an n-tridecyl group, an n-tetradecyl group, an n-pentadecyl group, an n-hexadecyl group, an n-heptadecyl group, an n-octadecyl group, an n-nonadecyl group, an n-icosyl group, an i-propyl group, a sec-butyl group, an i-butyl group, a t-butyl group, a 1-methylbutyl group, a 1-ethylpropyl group, a 2-methylbutyl group, an i-amyl group, a neopentyl group, a 1,2-dimethylpropyl group, a 1,1-dimethylpropyl group, a t-amyl group, a 1,3-dimethylbutyl group, a 3,3-dimethylbutyl group, and a 2-ethylbutyl group. aliphatic alkyl groups such as a 2-ethyl-2-methylpropyl group, a 1-methylheptyl group, a 2-ethylhexyl group, a 1,5-dimethylhexyl group, a t-octyl group, a branched nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, a stearyl group, and an icosyl group; and alicyclic alkyl groups such as a cyclopropyl group, a cyclopropylmethyl group, a cyclobutyl group, a cyclobutylmethyl group, a cyclopentyl group, a cyclohexyl group, a cyclohexylmethyl group, a cycloheptyl group, a cyclooctyl group, a cyclohexylpropyl group, a cyclododecyl group, a norbornyl group (C7), an adamantyl group (C10), and a cyclopentylethyl group.

[0053] Examples of the alkenyl group include 1-butenyl, 2-butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, dodecenyl, octadecenyl, and icosenyl groups. Examples of the alkynyl group include 2-propynyl, butynyl, pentynyl, hexynyl, heptynyl, octynyl, nonynyl, decynyl, dodecynyl, octadecynyl, and icosynyl groups.

[0054] Examples of the aryl group include a phenyl group, an o-, m- or p-tolyl group, a 2,3- or 2,4-xylyl group, a mesityl group, a naphthyl group, an anthryl group, a phenanthryl group, and a biphenylyl group. Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, and a benzhydryl group.

[0055] Above R 1 is preferably an alkyl group having 4 or more carbon atoms, or an aromatic group having 6 or more carbon atoms, more preferably an aryl group, and even more preferably a phenyl group.

[0056] R in the above formula (1) 3 is a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms. Specific examples of the hydrocarbon group include alkyl groups, alkenyl groups, alkynyl groups, aryl groups, and aralkyl groups. Specific examples of hydrocarbon groups having 4 to 30 carbon atoms are as described above, and examples of hydrocarbon groups having 1 to 3 carbon atoms include methyl groups, ethyl groups, propyl groups, isopropyl groups, vinyl groups, allyl groups, ethynyl groups, 1-propynyl groups, and 2-propynyl groups. The hydrocarbon group preferably has 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, even more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 4 carbon atoms. Above R 3 is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom or a methyl group.

[0057] The compound represented by the above formula (1) is preferably phenoxypolyethylene glycol, phenoxyethylpolyethylene glycol, naphthoxypolyethylene glycol, butoxypolyethylene glycol, hexyloxypolyethylene glycol, octyloxypolyethylene glycol, or stearyloxypolyethylene glycol, more preferably phenoxypolyethylene glycol.

[0058] The number average molecular weight of the compound represented by the formula (1) is preferably 100 to 100,000, more preferably 200 to 50,000, even more preferably 300 to 10,000, and particularly preferably 500 to 5,000. The number average molecular weight can be measured by GPC.

[0059] The monomer component to be graft polymerized onto the (poly)alkylene glycol having a hydrophobic group at its terminal includes an unsaturated carboxylic acid monomer. Specific examples and preferred embodiments of the unsaturated carboxylic acid monomer are as described above. The above-mentioned monomer component may contain other monomers in addition to the unsaturated carboxylic acid monomer. The other monomer components are not particularly limited, and examples thereof include: monomers having a sulfonic acid group such as 2-acrylamido-2-methylpropanesulfonic acid, (meth)allyl sulfonic acid, vinyl sulfonic acid, 2-hydroxy-3-allyloxy-1-propanesulfonic acid, and 2-hydroxy-3-butenesulfonic acid; monomers having a phosphonic acid group such as vinylphosphonic acid and (meth)allylphosphonic acid; hydrophilic monomers such as monomers having a hydroxyl group, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and α-hydroxymethylethyl (meth)acrylate; methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, and cyclohexyl (meth)acrylate; alkyl (meth)acrylates obtained by esterification of (meth)acrylic acid such as vinyl acrylate with alcohols having 1 to 18 carbon atoms; amide group-containing monomers such as (meth)acrylamide, dimethylacrylamide, and isopropylacrylamide; vinyl esters such as vinyl acetate; alkenes such as ethylene and propylene; aromatic vinyl monomers such as styrene and styrene sulfonic acid; maleimide derivatives such as maleimide, phenylmaleimide, and cyclohexylmaleimide; nitrile group-containing vinyl monomers such as (meth)acrylonitrile; aldehyde group-containing vinyl monomers such as (meth)acrolein; alkyl vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, and butyl vinyl ether; other functional group-containing monomers such as vinyl chloride, vinylidene chloride, allyl alcohol, and vinylpyrrolidone; and cationic monomers.

[0060] The cationic monomer is not particularly limited as long as it has a cationic group and an ethylenically unsaturated hydrocarbon group (unsaturated group). Examples of the cationic monomer include N,N-dialkylamino group-containing (meth)acrylates such as N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, and N,N-diethylaminopropyl (meth)acrylate, as well as their neutralization products with acids such as hydrochloric acid and acetic acid; N,N-dimethylaminoethyl (meth)acrylate; N,N-dialkylamino group-containing (meth)acrylamides such as acrylamide, N,N-diethylaminoethyl (meth)acrylamide, N,N-dimethylaminopropyl (meth)acrylamide, and N,N-diethylaminopropyl (meth)acrylamide, and their neutralization products with acids such as hydrochloric acid and acetic acid; monoalkylamino group-containing (meth)acrylates such as monomethylaminoethyl (meth)acrylate, monoethylaminoethyl (meth)acrylate, monomethylaminopropyl (meth)acrylate, monoethylaminopropyl (meth)acrylate, and 2-(tert-butylamino)ethyl (meth)acrylate, and their neutralization products with acids such as hydrochloric acid and acetic acid; monoalkylamino group-containing (meth)acrylamides such as monomethylaminoethyl (meth)acrylamide, monoethylaminoethyl (meth)acrylamide, monomethylaminopropyl (meth)acrylamide, and monoethylaminopropyl (meth)acrylamide, and their neutralization products with acids such as hydrochloric acid and acetic acid; (meth)acrylamides such as 2-aminoethyl (meth)acrylate, ) Esters of acrylic acid and alkanolamines and their neutralization products with acids such as hydrochloric acid and acetic acid; N,N-diallylmethylamine and its neutralization products with acids such as hydrochloric acid and acetic acid; allylamine and its neutralization products with acids such as hydrochloric acid and acetic acid; addition reaction products of unsaturated monomers having a cyclic ether-containing group having 2 to 8 carbon atoms, such as 1-allyloxy-3-dibutylamino-2-ol and 1-allyloxy-3-diethanolamino-2-ol, with amine compounds having 1 to 24 carbon atoms, and their neutralization products with acids such as hydrochloric acid and acetic acid.

[0061] The amine compound having 1 to 24 carbon atoms is not particularly limited as long as it has an amino group and can react with the cyclic ether structure of an unsaturated monomer having a cyclic ether-containing group having 2 to 8 carbon atoms. The number of carbon atoms in the amine compound having 1 to 24 carbon atoms is preferably 1 to 20, and more preferably 1 to 16. Examples of the amine compound having 1 to 24 carbon atoms include primary amines and secondary amines, such as (di)alkylamines having 1 to 24 carbon atoms, (di)alkanolamines having 1 to 24 carbon atoms, and alkylalkanolamines having 1 to 24 carbon atoms.

[0062] As the cationic monomer, preferred are N,N-dialkylamino group-containing (meth)acrylates and their neutralization products with acids such as hydrochloric acid, and monomers obtained by adding a quaternizing agent to these; N,N-dialkylamino group-containing (meth)acrylamides and their neutralization products with acids such as hydrochloric acid, and monomers obtained by adding a quaternizing agent to these; and among these, N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylamide and their neutralization products with acids such as hydrochloric acid, and monomers obtained by adding a quaternizing agent to these are more preferred. The quaternizing agent is not particularly limited, but examples thereof include common alkylating agents such as alkyl halides such as methyl chloride, ethyl chloride, methyl bromide, and methyl iodide; and alkyl sulfates such as dimethyl sulfate, diethyl sulfate, and di-n-propyl sulfate.

[0063] Although the graft amount of the monomer component in the graft polymer is not particularly limited, the mass ratio of the (poly)alkylene glycol moiety (B) represented by the formula (2) to the monomer-derived portion is preferably 50:50 to 90:10, more preferably 55:45 to 85:15, and even more preferably 60:40 to 80:20.

[0064] In the graft polymer, the proportion of structural units derived from unsaturated carboxylic acid monomers in the side chains formed by the monomer components is preferably 90 mol % or more, more preferably 92 mol % or more, even more preferably 95 mol % or more, particularly preferably 98 mol % or more, and most preferably 100 mol % relative to 100 mol % of all side chains.

[0065] In the graft polymer, the proportion of structural units derived from monomers other than the unsaturated carboxylic acid monomer in the side chains formed by the monomer components is preferably 10 mol % or less, more preferably 8 mol % or less, even more preferably 5 mol % or less, particularly preferably 2 mol % or less, and most preferably 0 mol % relative to 100 mol % of all side chains.

[0066] The number-average molecular weight of the graft polymer is not particularly limited, but is preferably 1,000 to 1,000,000, more preferably 1,500 to 500,000, and even more preferably 2,000 to 100,000. If the number-average molecular weight is 1,000,000 or less, the viscosity falls within a suitable range, resulting in excellent handleability. Furthermore, if the number-average molecular weight is 1,000 or more, even better dispersibility is exhibited. The number average molecular weight can be measured by GPC.

[0067] (Method for producing graft polymer) The method for producing the graft polymer is not particularly limited, and the graft polymer can be produced by a commonly used method by graft polymerizing a monomer component containing an unsaturated carboxylic acid monomer onto a (poly)alkylene glycol having a hydrophobic group at its terminal.

[0068] The method for producing the (poly)alkylene glycol having a hydrophobic group at the terminal is not particularly limited, and the (poly)alkylene glycol can be obtained by reacting an alkylene oxide with a compound having a hydrophobic group with which the alkylene oxide can react, but a commercially available product may also be used. The compound having a hydrophobic group with which alkylene oxide can react is not particularly limited, but examples thereof include alcohols having a hydrophobic group.

[0069] Examples of the alcohol having a hydrophobic group include the above-mentioned aromatic alcohols and alkyl alcohols, among which aromatic alcohols are preferred.

[0070] When carrying out the graft polymerization, the amounts of the (poly)alkylene glycol having a hydrophobic group at its terminal, which serves as the main chain, and the monomer components which serve as the side chains may be determined so as to achieve the composition ratio described for the graft polymer.

[0071] When the graft polymerization is carried out, it is preferable to use a polymerization initiator. The polymerization initiator is not particularly limited, and examples thereof include the radical polymerization initiators described in Patent Document 2. Preferred are di-tert-butyl peroxide, tert-butyl hydroperoxide, octanoyl peroxide, lauroyl peroxide, benzoyl peroxide, cumene hydroperoxide, etc., and more preferred is di-tert-butyl peroxide.

[0072] The amount of the radical polymerization initiator used is not particularly limited, but is preferably 0.1 to 15% by mass, more preferably 0.5 to 10% by mass, and even more preferably 1 to 7% by mass, relative to 100% by mass of the monomer components used in the graft polymerization.

[0073] During the graft polymerization, in addition to the radical polymerization initiator described above, a decomposition catalyst for the radical polymerization initiator or a reducing compound may be added to the reaction system. The reducing compound is preferably ascorbic acid or the like.

[0074] The polymerization of the graft polymer is preferably carried out in a non-aqueous system. It is also preferable to minimize the inclusion of solvents other than water, such as alcohols (e.g., isobutyl alcohol, n-butyl alcohol, tert-butyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, and propylene glycol) and toluenes. Specifically, the solvent content is preferably 5% by mass or less, more preferably 3% by mass or less, even more preferably 1% by mass or less, and most preferably 0% by mass, based on the total amount of the reaction system.

[0075] The temperature during graft polymerization is preferably 50°C or higher, more preferably 70°C or higher, and even more preferably 120 to 150°C.

[0076] The polymerization time is not particularly limited, but is preferably 60 to 420 minutes, more preferably 90 to 390 minutes, and even more preferably 120 to 360 minutes. In the present invention, the time when the unsaturated carboxylic acid monomer and the initiator come into contact with each other in the polymerization apparatus is defined as 0 minutes (polymerization initiation time).

[0077] The pressure in the reaction system may be normal pressure (atmospheric pressure), reduced pressure, or increased pressure, but from the viewpoint of the molecular weight of the resulting polymer, it is preferable to carry out the reaction at normal pressure or under increased pressure in a sealed reaction system. Furthermore, from the viewpoint of equipment such as a pressurizing device, a decompressor, a pressure-resistant reaction vessel, and piping, it is preferable to carry out the reaction at normal pressure (atmospheric pressure). The atmosphere in the reaction system may be an air atmosphere, but is preferably an inert atmosphere. For example, it is preferable to replace the atmosphere in the system with an inert gas such as nitrogen before the start of polymerization.

[0078] During graft polymerization, it is preferable to start polymerization by charging a part or all of the polyalkylene oxide that will form the main chain of the graft polymer into the reaction system. Of the monomer components, it is preferable to add the unsaturated carboxylic acid monomer dropwise after charging the polyalkylene oxide. For example, the entire amount of polyalkylene oxide is charged into the reaction system, the reaction system is heated to a predetermined temperature, and then the unsaturated carboxylic acid monomer and, if necessary, a radical polymerization initiator are separately added dropwise to allow the graft polymerization reaction to proceed. This type of reaction is preferable because it allows for easy adjustment of the molecular weight of the resulting graft polymer. The graft polymerization may be carried out in a batch, semi-batch, or continuous manner.

[0079] In the graft polymerization, after the dropwise addition is completed, stirring may be continued while maintaining the polymerization temperature, if necessary, for the purpose of reducing the amount of residual monomers. The stirring time is preferably 30 to 360 minutes, more preferably 60 to 180 minutes, and even more preferably 60 to 120 minutes.

[0080] The reaction product graft polymerized as described above may be subjected to a post-treatment in which a peroxide and / or an azo compound is added to the hydrophilic graft polymer in order to further reduce the amount of residual monomer. The peroxides and azo compounds are not particularly limited, and examples thereof include the peroxides and azo compounds described in Patent Document 2. The compound used in the post-treatment is preferably a peroxide. When a peroxide is used, it is preferable that the peroxide is different from the polymerization initiator used during polymerization. When a peroxide is used in the post-treatment, it is preferable to use a decomposition accelerator that can accelerate the decomposition of the peroxide together with the peroxide. Examples of the decomposition accelerator include reducing agents such as amines, ascorbic acid, and iron, and alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, and one or more of these can be used.

[0081] The temperature during the post-treatment is preferably 100°C or lower, more preferably 80°C or lower, and even more preferably 60°C or lower. The post-treatment is preferably performed at room temperature (20 to 25°C) or higher. It may be performed under reflux. The post-treatment time varies depending on the reaction temperature and the type of additive used, but is preferably 10 minutes or longer, more preferably 30 minutes or longer, and even more preferably 60 to 120 minutes.

[0082] The amount of peroxide and / or azo compound used in the post-treatment is preferably 0.01 to 10% by mass, more preferably 0.05 to 5% by mass, and even more preferably 0.1 to 2% by mass, relative to the graft polymer. Within this range, the effect of reducing residual unsaturated carboxylic acid can be sufficiently achieved. Furthermore, when a reducing agent is used in combination with the peroxide, the amount used is preferably 0.01 to 10% by mass, more preferably 0.05 to 5% by mass, and even more preferably 0.1 to 2% by mass, relative to the hydrophilic graft polymer.

[0083] <Nonionic surfactant> The nonionic surfactant is not particularly limited as long as it has a hydrophobic group and a hydrophilic group that does not dissociate into ions. Examples of the nonionic surfactant include surfactants represented by the following formulae (3-1) to (3-7): HO-(CH2CH2O) k -(R 4 O) l -(CH2CH2O) m -H (3-1) HO-(R 5 O) o -(CH2CH2O) p -(R 6 O) q -H (3-2) R 7 -O-(R 8 O) r -H (3-3) R 9 -COO-(R 10 O) s -R 11 (3-4)

[0084] [ka]

[0085] (In the formula, R 4 O, R 5 O, R 6 O, R 12 O may be the same or different and represent an oxyalkylene group having 3 to 18 carbon atoms. k, l, m, o, p, and q may be the same or different and represent an integer of 1 to 100. R 7 , R 9 , R 13 are the same or different and represent a hydrocarbon group having 6 to 24 carbon atoms. 11 represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. 8 O, R 10 O, R 14 O are the same or different and represent an oxyalkylene group having 2 to 18 carbon atoms. r and s are the same or different and represent an integer of 1 to 50. t1 to t8 and u1 to u8 are the same or different and represent an integer of 1 to 100. x and y are the same or different and represent an integer of 1 to 100. Above R 8 O, R 10 O, R 14 When O has two or more types of oxyalkylene groups, that is, when O is an alkylene oxide adduct of two or more types, the addition may be in any form such as random addition, block addition, or alternating addition.

[0086] Above R 4 O, R 5 O, R 6 O, R 12 Specific examples of O include oxyalkylene groups having a carbon number of 3 to 18. Among these, an oxypropylene group and an oxybutylene group are preferred, and an oxypropylene group is more preferred.

[0087] The above k+m is preferably 1-30, and more preferably 5-20. The above l is preferably 5-50, and more preferably 15-40. The above o+q is preferably 5-60, and more preferably 5-40. The above p is preferably 1-30, and more preferably 1-20.

[0088] Above R 7 , R 9 , R 13 The hydrocarbon group in is not particularly limited, and examples thereof include an alkyl group, an alkenyl group, an aryl group, and an aralkyl group. The alkyl group and the alkenyl group may be linear or branched. Specific examples of the alkyl group, the alkenyl group, the aryl group, and the aralkyl group are as described above. R 13 The hydrocarbon group in the formula (I) is preferably an alkyl group having 6 to 22 carbon atoms.

[0089] Above R 7 , R 9 , R 13 The hydrocarbon group in has 6 to 24 carbon atoms, preferably 6 to 22 carbon atoms, more preferably 6 to 20 carbon atoms, and even more preferably 6 to 18 carbon atoms.

[0090] Above R 8 O, R 10 O, R 14 Specific examples and preferred forms of O include oxyalkylene groups having a carbon number of 3 to 18. Of these, an oxypropylene group and an oxybutylene group are preferred, and an oxypropylene group is more preferred.

[0091] The above r and s are preferably 1-100, more preferably 1-50, and even more preferably 3-30.

[0092] The above t1+t2+t3+t4 is preferably 5-400, and more preferably 15-200. The above u1+u2+u3+u4 is preferably 4-200, and more preferably 5-40. The above t5+t6+t7+t8 is preferably 5-400, and more preferably 15-200. The above u5+u6+u7+u8 is preferably 4-200, and more preferably 5-40.

[0093] The nonionic surfactants represented by the above formulas (3-1) and (3-2) are preferably polyethylene glycol-polypropylene glycol block copolymers, etc. The total number of moles of EO and PO added in the copolymer is more preferably 6 to 100, and even more preferably 20 to 60.

[0094] The nonionic surfactants represented by the above formulas (3-3) and (3-4) are preferably compounds in which 1 to 100 moles of ethylene oxide (EO) and / or propylene oxide (PO) are added to an alkyl alcohol having 6 to 24 carbon atoms. The total number of moles of EO and PO added in the above compounds is more preferably 1 to 50, even more preferably 2 to 40, and particularly preferably 3 to 30. The alkyl alcohol may be linear or branched, and the alkyl alcohol in the form of a primary or secondary alcohol is one of the preferred embodiments of the present invention.

[0095] The nonionic surfactants represented by the above formulas (3-5) and (3-6) are preferably compounds in which 10 to 800 moles of ethylene oxide (EO) and / or propylene oxide (PO) are added to ethylenediamine (polyoxyethylene and polyoxypropylene block polymers of ethylenediamine). The total number of moles of EO and PO added in the above compounds is more preferably 10 to 500, and even more preferably 20 to 300.

[0096] The nonionic surfactant represented by the formula (3-7) is preferably a compound (polyoxyalkylene alkylamine) in which 1 to 200 moles of ethylene oxide (EO) and / or propylene oxide (PO) are added to an amine having a hydrocarbon group with 6 to 24 carbon atoms. The total number of moles of EO and PO added in the compound is more preferably 2 to 100, and even more preferably 2 to 50.

[0097] The nonionic surfactant is preferably a compound represented by the above formula (3-1) or (3-2), more preferably a compound represented by the above formula (3-1).

[0098] <Compounds that exhibit neutral to basic properties in aqueous solution> The compound that exhibits a neutral to basic property in an aqueous solution is not particularly limited as long as it is a compound that has a pH of 6 or higher when made into a 10% by mass aqueous solution (25°C), and examples thereof include hydroxides, carbonates, hydrogencarbonates, oxides, silicates, polycarboxylic acids, and aminocarboxylic acids of alkali metals such as sodium and potassium; hydroxides and carbonates of alkaline earth metals such as barium, magnesium, calcium, and strontium; hydroxides of transition metals such as lanthanum and cerium; and alkanolamines. The above compounds that are neutral to basic in aqueous solution preferably have a pH of 6.5 to 14, more preferably 7 to 13.5, even more preferably 7.5 to 13, and particularly preferably 8 to 12.5, when prepared as a 10% by mass aqueous solution (25°C). The pH of the aqueous solution can be measured with a pH meter. Of the above compounds, preferred are compounds that exhibit basicity in aqueous solution, more preferred are alkali metal hydroxides, carbonates and citrates, and even more preferred are sodium hydroxide, potassium hydroxide, sodium carbonate and potassium carbonate.

[0099] <Solubilizer> The solubilizing agent is not particularly limited as long as it is a compound that has the function of dissolving an agent that does not hydrate when mixed with other components and is low-foaming, but preferred examples include aromatic sulfonic acids or salts thereof such as p-toluenesulfonic acid, xylenesulfonic acid, cumenesulfonic acid, substituted or unsubstituted naphthalenesulfonic acid, or salts thereof, ethanol, propylene glycol, butyl diglycol, alkyldimethylamine oxides having 6 to 10 carbon atoms, and alkylglucosides having 6 to 10 carbon atoms. Among these, preferred are p-toluenesulfonic acid, xylenesulfonic acid, cumenesulfonic acid, substituted or unsubstituted naphthalenesulfonic acid, or salts thereof.

[0100] <Other ingredients> Examples of the other components include solvents, chelating agents, stabilizers, enzymes, antifoaming agents, dyes, fragrances, and preservatives.

[0101] [Application] The liquid detergent composition of the present invention contains a nonionic surfactant, but has excellent cleaning power while reducing the amount of solubilizer used, so it can be suitably used in objects and situations where low foaming is required. In one embodiment, the liquid detergent composition can be suitably used in a cleaning machine that sprays a cleaning liquid or the like to remove dirt from a target. The liquid detergent composition may be used in a spray cleaner or in a device other than a spray cleaner.

[0102] The cleaning target of the liquid detergent composition of the present invention is not particularly limited, and examples thereof include hard surfaces such as ceramics, metals, and resins. Specific examples of hard surfaces that can be cleaned include tableware, cooking utensils, the interior of a washing machine, toilets, bathtubs, windows, mirrors, transport vehicles, floors, piping, manufacturing equipment, electronic equipment components, and separation membranes. More preferred cleaning targets are tableware, cooking utensils, and the interior of a washing machine. The liquid detergent composition of the present invention can also be used in the CMP process in semiconductor manufacturing.

[0103] The spray type washer is not particularly limited, but is preferably a device that automatically washes the above-mentioned objects to be washed, and more preferably an automatic dishwasher. [Example]

[0104] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "parts" means "parts by weight" and "%" means "% by mass."

[0105] [Synthesis of PAG compounds] <Synthesis Example 1> A 2-L stainless steel reactor equipped with a thermometer, stirrer, nitrogen inlet tube, and reflux condenser was charged with 465 parts of phenoxypolyethylene glycol (average molecular weight 974, 20 moles of ethylene oxide added) melted at 60°C or higher. The mixture was heated to 120°C under a nitrogen stream and stirring. Next, while maintaining the temperature at 125-131°C, 7.8 parts of di-tert-butyl peroxide (Kayaku Butyl D, manufactured by Kayaku Akzo Co., Ltd.) was added dropwise over 195 minutes. 20 minutes after the start of the di-tert-butyl peroxide addition, 181 parts of acrylic acid (100 mol% molar ratio of the monomer) was added dropwise over 225 minutes, followed by 70 minutes of stirring. The mixture was then cooled to 60°C, diluted with 267 parts of water, and treated at 60°C for 1 hour with 42 parts of 2% aqueous hydrogen peroxide and 42 parts of 2% aqueous L-ascorbic acid. 18 parts of this graft polymer aqueous solution were mixed with 3 parts of a 48% aqueous sodium hydroxide solution and 80 parts of water to obtain an aqueous polymer (1) solution with a solid content of 12%.

[0106] [Preparation of Liquid Detergent Composition] Example 1 87.9 parts of the aqueous solution of polymer (1), 1.1 parts of Pronon 202B (NOF Corporation), and 11 parts of a 48% aqueous solution of sodium hydroxide were placed in a beaker and mixed with stirring to obtain a detergent composition (1).

[0107] <Example 2> 27.3 parts of the polymer (1) aqueous solution, 56 parts of ion-exchanged water, 5.0 parts of Pronon 202B (NOF Corporation), 5.0 parts of citric acid, and 6.7 parts of 48% sodium hydroxide aqueous solution as a pH adjuster were placed in a beaker and stirred to obtain a detergent composition (2). Example 3 83.8 parts of the aqueous solution of polymer (1), 0.8 parts of ion-exchanged water, 10.4 parts of a 48% aqueous sodium hydroxide solution, and 5.0 parts of sodium carbonate were placed in a beaker and mixed with stirring until homogeneous, to obtain a detergent composition (3).

[0108] <Comparative Example 1> 1.1 parts of Pronon 202B (NOF Corporation), 87.9 parts of ion-exchanged water, and 11 parts of 48% aqueous sodium hydroxide solution were placed in a beaker and mixed with stirring to obtain a comparative detergent composition (1).

[0109] <Comparative Example 2> A beaker was charged with 11 parts of trisodium 2-methylnitrilotriacetate (Tokyo Chemical Industry Co., Ltd.), 1.1 parts of Pronon 202B (NOF Corporation), 76.9 parts of ion-exchanged water, and 11 parts of 48% aqueous sodium hydroxide solution, and the mixture was stirred to obtain a comparative detergent composition (2).

[0110] <Comparative Example 3> 24.4 parts of an aqueous solution of sodium polyacrylate (YS-100, Nippon Shokubai Co., Ltd., polymer purity: 45%), 1.1 parts of Pronon 202B (NOF Corporation), 63.5 parts of ion-exchanged water, and 11 parts of a 48% aqueous solution of sodium hydroxide were placed in a beaker and stirred to obtain a comparative detergent composition (3).

[0111] <Comparative Example 4> A beaker was charged with 5.0 parts of Pronon 202B (NOF Corporation), 83.3 parts of ion-exchanged water, 5.0 parts of citric acid, and 6.7 parts of 48% aqueous sodium hydroxide solution as a pH adjuster, and the mixture was stirred to obtain a comparative detergent composition (4). <Comparative Example 5> A beaker was charged with 5.0 parts of Pronon 202B (NOF Corporation), 71.1 parts of ion-exchanged water, 10.0 parts of citric acid, and 13.9 parts of 48% aqueous sodium hydroxide solution as a pH adjuster, and the mixture was stirred to obtain a comparative detergent composition (5). <Comparative Example 6> 84.6 parts of ion-exchanged water, 10.4 parts of a 48% aqueous sodium hydroxide solution, and 5.0 parts of sodium carbonate were placed in a beaker and mixed with stirring until uniform, to obtain a comparative detergent composition (6).

[0112] <Comparative Example 7> 10.0 parts of trisodium 2-methylnitrilotriacetate, 74.6 parts of ion-exchanged water, 10.4 parts of 48% aqueous sodium hydroxide solution, and 5.0 parts of sodium carbonate were placed in a beaker and mixed with stirring until homogeneous, to obtain a comparative detergent composition (7).

[0113] <Comparative Example 8> 10.0 parts of sodium p-toluenesulfonate (hereinafter referred to as p-TSS), 74.6 parts of ion-exchanged water, 10.4 parts of 48% aqueous sodium hydroxide solution, and 5.0 parts of sodium carbonate were placed in a beaker and mixed with stirring until homogeneous, to obtain a comparative detergent composition (8).

[0114] [Evaluation of physical properties of liquid detergent compositions] The compatibility of the detergent composition (1) prepared in Example 1 and the comparative detergent compositions (1) to (3) prepared in Comparative Examples 1 to 3 was evaluated as follows. Compatibility test (1) The compatibility of each detergent composition at room temperature was visually evaluated according to the following evaluation criteria. The results are shown in Table 1. 〇: Uniform and transparent with no precipitation or cloudiness ×: Precipitation or cloudiness

[0115] [Table 1] 1) Pronon 202B (NOF Corporation)

[0116] The above detergent compositions (1) to (2) and comparative detergent compositions (1) to (5) reach or exceed the cloud point at 40°C, where the nonionic surfactant becomes insoluble and forms a heterogeneous solution. Therefore, the amount of solubilizer required to maintain a homogeneous, transparent solution at 40°C was investigated using the following method. Compatibility test (2) 91 g of each detergent composition was adjusted to 40°C, p-TSS was added as a solubilizer, and the mixture was stirred. The amount of p-TSS added when the mixture became uniform and transparent was compared. The results are shown in Tables 2 and 3. p-TSS is a component that does not contribute to the cleaning performance of liquid detergents, so the smaller the amount added, the better.

[0117] [Table 2] [Table 3] 1) Pronon 202B (NOF Corporation)

[0118] The detergent composition (3) and the comparative detergent compositions (6) to (8) were subjected to a scale prevention test and / or a redeposition prevention test by the following method. ·Scale prevention test 40 μL of each of the detergent composition (3) and comparative detergent compositions (6) to (8) was placed in a glass vial and diluted 1000 times with hard water (Ca:Mg = 3:1 molar ratio) adjusted to 200 mg CaCO3 / L. This was left to stand at 60°C for 24 hours, and the aqueous solution was removed from the vial and the amount of scale deposited on the container wall was visually evaluated according to the following criteria. The results are shown in Table 4. 〇: No scale has been deposited on the inner wall of the glass container, and it remains clear and clean. ×: Scale is deposited on the inner wall of the glass container, and it has turned white.

[0119] [Table 4]

[0120] Anti-recontamination test 50 g of uniformly mixed beaten egg was added to 450 g of water heated to 100°C and heated for 1 minute. The mixture was then mixed in a mixer (Iwatani, Fresh Mill IFM-FR10-R) until no precipitate remained, yielding a 10% soil solution. 10 g of this mixture was placed in a beaker, to which 90 g of tap water and 100 μL of the above-mentioned detergent composition (3) or comparative detergent composition (6) or (8) were added. The mixture was heated and stirred at 60°C for 30 minutes to obtain a soil-containing cleaning solution. A glass plate (Matsunami Glass Industry Co., Ltd., S1112) was immersed in the solution for 20 seconds, rinsed with tap water for 5 seconds, and air-dried, repeating this cycle three times. The plate was then immersed in 0.05% amido black acetic acid solution for protein staining for 1 minute, rinsed with tap water for 5 seconds, and air-dried. Both sides of the recontaminated plate were thoroughly wiped with a cotton swab, and the swab was washed with 3.5 g of 1 mmol / L aqueous sodium hydroxide to extract the amido black. The absorbance at 620 nm was measured using a spectrophotometer (Shimadzu, UV-1800) to quantify the amount of amido black. The results are shown in Table 5. It should be noted that since amido black adsorbs to proteins that have redeposited on the glass plate, the smaller the amount of amido black, the better the glass plate's ability to prevent redeposition.

[0121] [Table 5]

Claims

1. A liquid detergent composition comprising a (poly)alkylene glycol-containing compound and a nonionic surfactant, The (poly)alkylene glycol-containing compound has a hydrophobic structural portion (A), a (poly)alkylene glycol portion (B), and a carboxylic acid (salt) group-containing structural portion (C), The liquid detergent composition contains the nonionic surfactant in an amount of 0.01 to 20% by mass relative to 100% by mass of the composition.

2. 2. The liquid detergent composition according to claim 1, wherein the content of the (poly)alkylene glycol-containing compound is 0.01 to 20% by mass relative to 100% by mass of the composition.

3. 2. The liquid detergent composition according to claim 1, wherein the proportion of the carboxylic acid (salt) group-containing structural moiety (C) in the (poly)alkylene glycol-containing compound is 1 to 50 mass % relative to 100 mass % of the compound.

4. The liquid detergent composition according to claim 1, wherein the (poly)alkylene glycol-containing compound has a main chain having a hydrophobic structural portion (A) and a (poly)alkylene glycol portion (B), and a side chain formed by graft polymerization of a monomer component containing an unsaturated carboxylic acid monomer onto the main chain.

5. The (poly)alkylene glycol-containing compound is represented by the following formula (1): R １ -O-(R ２ O) ｎ -R ３ (1) (In the formula, R １ represents a hydrophobic group. ２ O may be the same or different and represent an oxyalkylene group having 2 to 18 carbon atoms. n represents the average number of moles of oxyalkylene groups added and is a number from 1 to 500. R ３ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms.) and a monomer component containing an unsaturated carboxylic acid monomer.

6. R in the formula (1) １ 6. The liquid detergent composition according to claim 5, wherein the hydrophobic group is an organic group having 4 or more carbon atoms.

7. R in the formula (1) １ 6. The liquid detergent composition according to claim 5, wherein the hydrophobic group is an alkyl group having 4 or more carbon atoms or an aromatic group having 6 or more carbon atoms.

8. The liquid detergent composition according to claim 1, further comprising a compound that exhibits neutral to basic properties in an aqueous solution.

9. The liquid detergent composition according to claim 8, wherein the content of the compound that is neutral to basic in an aqueous solution is 1 to 30% by mass relative to 100% by mass of the composition.

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