Copolymers, compositions and additives for cleaning agents

Abstract

A copolymer having: a structural unit (A) represented by equation (1) below and / or a structural unit (A) represented by equation (7) below. 02), and structural unit (B) represented by the following formula (2) and / or structural unit (C) represented by the following formula (3). [In the formula, R] 1 represents a hydrogen atom or -C(=O)-X, R 2 represents a hydrogen atom or a methyl group, X represents a substituted aryl group or a substituted alkyl group having 1 to 4 carbon atoms, and R represents a substituted alkyl group. 3 indicates an alkyl group with 1 to 4 carbon atoms, m indicates an integer from 0 to 30, and R 4 represents an alkyl group with 1 to 4 carbon atoms, and n represents an integer from 0 to 30.

Description

Copolymer, composition and cleaning agent additive The present disclosure relates to a copolymer, a composition and an additive for a cleaning agent. Conventionally, detergents used for clothing and the like have been formulated with detergent additives such as zeolite, carboxymethyl cellulose, polyethylene glycol, and (meth)acrylic acid polymers for the purpose of improving the cleaning effect of the detergents. For example, Patent Document 1 proposes a (meth)acrylic acid copolymer comprising structural units derived from a monoethylenically unsaturated carboxylic acid, an alkyl (meth)acrylate, and an alkoxylated (meth)acrylate monomer as a laundry detergent formulation. [Prior Art Document] [Patent Document] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-3551 [Problems to be Solved by the Invention] However, conventional detergent additives such as the (meth)acrylic acid polymer described in Patent Document 1 have room for improvement in terms of cleaning of oil stains and the like. Therefore, an object of the present disclosure is to provide a copolymer having excellent cleaning performance for oil stains when used as a detergent additive, for example, and a composition and detergent additive containing the copolymer. [Means for Solving the Problem] The present disclosure provides the following copolymers described in [1] to [8], the composition described in [9], the detergent additive described in

[10] , the use described in

[11] , and the cleaning method described in

[12] . [1] A copolymer having: a structural unit (A) represented by the following formula (1) and / or a structural unit (A) represented by the following formula (7) 02 ), and a structural unit (B) represented by the following formula (2) and / or a structural unit (C) represented by the following formula (3). [Chemistry 1] [In formula (1), R 1 Represents a hydrogen atom or -C(=O)-X, R 2 represents a hydrogen atom or a methyl group; X represents an optionally substituted aryl group or an optionally substituted alkyl group having 1 to 4 carbon atoms] [Chemistry 2] [In formula (7), R 2 represents a hydrogen atom or a methyl group] [Chemistry 3] [In formula (2), R 3 represents an alkyl group having 1 to 4 carbon atoms, and m represents an integer of 0 to 30] [Chemical 4] [In formula (3), R 4represents an alkyl group having 1 to 4 carbon atoms, and n represents an integer of 0 to 30] [2] The copolymer described in [1], comprising a structural unit (A), a structural unit (B) and a structural unit (C). [3] A copolymer comprising: a structural unit (A) represented by the following formula (5) 0 ), and the structural unit (B) represented by the formula (2) and / or the structural unit (C) represented by the formula (3). [Chemistry 5] [In formula (5), R 2 represents a hydrogen atom or a methyl group, R 9 [4] The copolymer as described in [3], wherein the structural unit (A 0 ) includes a structural unit represented by the following formula (6) (A 01 ) and / or a structural unit represented by the following formula (7) (A 02 ). [Chemistry 6] [In formula (6), R 1 Represents a hydrogen atom or -C(=O)-X, R 2 represents a hydrogen atom or a methyl group; X represents an optionally substituted aryl group or an optionally substituted alkyl group having 1 to 4 carbon atoms] [Chemistry 7] [In formula (7), R 2 represents a hydrogen atom or a methyl group] [5] The copolymer as described in [1] or [2], wherein the content of the structural unit (A) in the copolymer is 5% by mass or more and 98% by mass or less, the content of the structural unit (B) in the copolymer is 1% by mass or more and 50% by mass or less, and the content of the structural unit (C) in the copolymer is 1% by mass or more and 60% by mass or less. [6] The copolymer as described in [1], [2] or [4], wherein R 1 is at least one selected from a hydrogen atom and -C(=O)-X wherein X is an o-hydroxyphenyl group. [7] The copolymer according to any one of [1] to [6], wherein m is 0 and R 3 [8] The copolymer according to any one of [1] to [7], wherein n is 0 and R 4 is ethyl, or n is 5 to 30 and R 4 is a methyl group. [9] The copolymer according to any one of [1] to [8], wherein the content of the structural unit (structural unit (X)) formed using 2-vinyl-2-oxazoline and / or 2-isopropenyl-2-oxazoline as a monomer in the copolymer is 0% by mass or more and 49% by mass or less.

[10] A composition comprising the copolymer according to any one of [1] to [9] and water.

[11] A detergent additive comprising the copolymer according to any one of [1] to [9] or the composition according to [9].

[12] A use of the copolymer according to any one of [1] to [9] as a detergent additive.

[13] A washing method using the copolymer according to any one of [1] to [9]. [Effects of the Invention] The present disclosure can provide a copolymer having excellent cleaning performance for oil stains when used as a detergent additive, a composition containing the copolymer, and a detergent additive. Hereinafter, the embodiments of the present disclosure will be described in detail. However, the present disclosure is not limited to the following embodiments. In the following description, "(meth)acrylic acid" is used as a term that includes both methacrylic acid and acrylic acid. In addition, when a numerical range is expressed as X to Y, it means greater than X and less than Y. For example, "5 nm to 100 nm" means greater than 5 nm and less than 100 nm. In this specification, unless otherwise specified, the exemplified materials or components may be used alone or in combination of two or more. [Copolymer] A copolymer according to one embodiment of the present disclosure comprises: a structural unit (A) and / or a structural unit (A 02 ), and structural unit (B) and / or structural unit (C). According to the copolymer, when used as an additive for cleaning agents, the cleaning performance of oil stains is excellent. Furthermore, each structural unit in the copolymer may be a single type or a combination of two or more. For example, in the copolymer, as structural unit (A), only R 1 This type of structural unit is a hydrogen atom and may also have R 1 The structural unit of hydrogen atom and R 1 These two are the structural units of -C(=O)-X. Another embodiment of the present disclosure includes a copolymer having a structural unit (A), a structural unit (B), and a structural unit (C). When used as a detergent additive, the copolymer has excellent oil-washing performance. Furthermore, each structural unit in the copolymer may be a single type or a combination of two or more types. For example, in the copolymer, as structural unit (A), only R 1 This type of structural unit is a hydrogen atom and may also have R 1 The structural unit of hydrogen atom and R 1 These two are the structural units of -C(=O)-X. Another embodiment of the copolymer disclosed herein has: structural units (A 0 ), and structural units (B) and / or structural units (C). When used as a detergent additive, the copolymer exhibits excellent cleaning performance against oily stains. Furthermore, each structural unit in the copolymer may be a single type or a combination of two or more. Hereinafter, each structural unit will be described. <Structural unit (A), structural unit (A 02 )> The structural unit (A) is a structural unit represented by the following formula (1), and the structural unit (A 02 ) is a structural unit represented by the following formula (7). [Chemistry 8] [Chemistry 9] In formula (1), R 1 represents a hydrogen atom or -C(=O)-X. X represents an optionally substituted aryl group or an optionally substituted alkyl group having 1 to 4 carbon atoms. The optionally substituted aryl group and the optionally substituted alkyl group having 1 to 4 carbon atoms may have one or more substituents. Examples of such substituents include hydroxyl, alkoxy, acyl, alkoxycarbonyl, and carbamoyl. R 1 Preferably, it is at least one selected from a hydrogen atom and -C(=O)-X, wherein X is an aryl group which may be substituted with a hydroxy group. More preferably, it is at least one selected from a hydrogen atom and -C(=O)-X, wherein X is an o-hydroxyphenyl group. Still more preferably, it is only a hydrogen atom, or -C(=O)-X, wherein a hydrogen atom and X are o-hydroxyphenyl groups. Yu R 1In the case of -C(═O)-X where X is a hydrogen atom and o-hydroxyphenyl, the ratio is preferably 99 parts by mass:1 part by mass to 30 parts by mass:70 parts by mass, more preferably 95 parts by mass:5 parts by mass to 40 parts by mass:60 parts by mass, and even more preferably 90 parts by mass:10 parts by mass to 50 parts by mass:50 parts by mass. In formula (1) and / or formula (7), R 2 represents a hydrogen atom or a methyl group, preferably a methyl group. Structural unit (A) and / or structural unit (A 02 ) can be formed, for example, by further opening the oxazoline ring of a structural unit formed using 2-vinyl-2-oxazoline or 2-isopropenyl-2-oxazoline as a monomer. If 2-vinyl-2-oxazoline is used as a monomer, R 2 The structural unit (A) and / or the structural unit (A 02 ), if 2-isopropenyl-2-oxazoline is used as a monomer, R 2 The structural unit (A) and / or the structural unit (A 02 Furthermore, during the ring-opening of the oxazoline ring, a portion of the oxazoline ring may not be opened, and structural units formed by using 2-vinyl-2-oxazoline and / or 2-isopropenyl-2-oxazoline as monomers may remain in the copolymer. Structural unit (A) and structural unit (A) in the copolymer 02 ) and the total content of structural units formed using 2-vinyl-2-oxazoline and / or 2-isopropenyl-2-oxazoline as monomers are preferably 100:0 to 20:80, more preferably 100:0 to 30:70, further preferably 100:0 to 40:60, further preferably 100:0 to 50:50, and particularly preferably 100:0 to 70:30, in terms of molar ratio. The ratio of the content of the structural unit (A) in the copolymer to the total content of the structural units formed using 2-vinyl-2-oxazoline and / or 2-isopropenyl-2-oxazoline as monomers (hereinafter also referred to as structural units (X)) is preferably 100:0 to 20:80, more preferably 100:0 to 30:70, further preferably 100:0 to 40:60, further preferably 100:0 to 50:50, and particularly preferably 100:0 to 70:30, in terms of molar ratio. The ring opening of the oxazoline ring can be carried out, for example, by hydrolysis under commonly used acidic conditions. 1 The structural unit (A) represented by the formula (1) and / or the structural unit (A 02 In this case, the ring-opening rate of the oxazoline ring can be adjusted by sampling the reaction solution midway and performing the reaction while confirming the ring-opening rate of the oxazoline ring. If a carboxylic acid is coexisted during the ring-opening of the oxazoline ring, a group derived from the carboxylic acid can be used as R 1 For example, if benzoic acid is used as the carboxylic acid, -C(=O)-X where X is a phenyl group can be introduced as R 1 If salicylic acid is used as the carboxylic acid, -C(=O)-X where X is o-hydroxyphenyl can be introduced as R 1 . Structural unit (A) and structural unit (A) in the copolymer 02 ) is preferably at least 5 mass % and at most 98 mass %, more preferably at least 10 mass % and at most 98 mass %, more preferably at least 15 mass % and at most 98 mass %, more preferably at least 25 mass % and at most 98 mass %, further preferably at least 30 mass % and at most 96 mass %, further preferably at least 40 mass % and at most 90 mass %. The content of the structural unit (A) in the copolymer is preferably 5% by mass or more and 98% by mass or less, more preferably 10% by mass or more and 98% by mass or less, even more preferably 15% by mass or more and 98% by mass or less, even more preferably 25% by mass or more and 98% by mass or less, further preferably 30% by mass or more and 96% by mass or less, and particularly preferably 40% by mass or more and 90% by mass or less. Structural units in the copolymer (A 02 ) may be 0 mass %, preferably 1 mass % or more and 98 mass % or less, more preferably 3 mass % or more and 98 mass % or less, further preferably 5 mass % or more and 96 mass % or less, and particularly preferably 10 mass % or more and 90 mass % or less. The content of the structural unit formed using 2-vinyl-2-oxazoline and / or 2-isopropenyl-2-oxazoline as a monomer (structural unit (X)) in the copolymer can be 0 mass %, preferably 0 mass % to 49 mass %, more preferably 0 mass % to 48 mass %, and even more preferably 0 mass % to 45 mass %. <Structural unit(A 0 ), structural unit (A 01 )> Structural unit(A 0 ) is a structural unit represented by the following formula (5). [Chemical 10] In formula (5), R 2 represents a hydrogen atom or a methyl group, R 9 It represents a group having a structure formed by ring-opening an oxazoline ring by reacting water and / or a carboxylic acid as a raw material compound. As R 9 , which can be exemplified by -C(=O)-NHCH 2CH 2OR 1 、-C(=O)-OCH 2CH 2NR 1 (R 1 ) etc. 1 Compared with R in formula (1) 1 same). Furthermore, the “structural unit having a structure formed by ring-opening an oxazoline ring by allowing water and / or carboxylic acid to act as a raw material compound” only needs to have a structure formed by ring-opening an oxazoline ring by allowing water and / or carboxylic acid to act as a raw material compound, and is not actually limited to a structure formed by ring-opening an oxazoline ring by allowing water and / or carboxylic acid to act as a raw material compound. The structural unit represented by formula (5) (A 0 ) For example, it can be a structural unit formed by further opening the oxazoline ring of a structural unit formed using 2-vinyl-2-oxazoline or 2-isopropenyl-2-oxazoline as a monomer. The oxazoline ring can be opened by hydrolysis under commonly used acidic conditions. This is equivalent to the case where the oxazoline ring is opened by allowing water to act as a raw material compound. On the other hand, if a carboxylic acid is coexisted during the ring opening of the oxazoline ring, a group derived from the carboxylic acid can be introduced. This is equivalent to the case where the oxazoline ring is opened by allowing water and a carboxylic acid to act as raw material compounds. Structural units in the copolymer (A 0 ) content, and the ratio of the total content of structural units formed using 2-vinyl-2-oxazoline and / or 2-isopropenyl-2-oxazoline as monomers is preferably 100:0 to 20:80, more preferably 100:0 to 30:70, further preferably 100:0 to 40:60, further preferably 100:0 to 50:50, and particularly preferably 100:0 to 70:30, in terms of molar ratio. As a structural unit (A 0 ), preferably, the structural unit (A 02 ) and the following structural units (A 01 ). Structural units in the copolymer (A 0 ) is more preferably from 10 mass % to 98 mass %, more preferably from 15 mass % to 98 mass %, more preferably from 25 mass % to 98 mass %, further preferably from 30 mass % to 96 mass %, further preferably from 40 mass % to 90 mass %. Structural unit (A 01 ) is a structural unit represented by the following formula (6). [Chemical 11] R in formula (6) 1 and R 2 The embodiment and preferred embodiment are the same as those of formula (1). Structural units in the copolymer (A 01 ) and structural units (A 02 ) and the total content of structural units formed using 2-vinyl-2-oxazoline and / or 2-isopropenyl-2-oxazoline as monomers are preferably 100:0 to 20:80, more preferably 100:0 to 30:70, further preferably 100:0 to 40:60, further preferably 100:0 to 50:50, and particularly preferably 100:0 to 70:30, in terms of molar ratio. Structural units in the copolymer (A 01) is preferably at least 5 mass % and at most 98 mass %, more preferably at least 10 mass % and at most 98 mass %, more preferably at least 15 mass % and at most 98 mass %, even more preferably at least 25 mass % and at most 98 mass %, further preferably at least 30 mass % and at most 96 mass %, particularly preferably at least 40 mass % and at most 90 mass %. <Structural unit (B)> Structural unit (B) is a structural unit represented by the following formula (2). In formula (2), R 3 represents an alkyl group having 1 to 4 carbon atoms. 3 Preferred is an alkyl group having 1 to 2 carbon atoms, and more preferred is a methyl group. In formula (2), m represents an integer of 0 to 30. Preferably, m is 0. In formula (2), when m is 0, R 3 Methyl is preferred. When m is 1 to 30, especially 5 to 30, R 3 Preferred is a methyl group or an ethyl group, and more preferred is a methyl group. The structural unit (B) in which m is 0 can be formed, for example, by using alkyl methacrylate as a monomer. For example, if methyl methacrylate is used as a monomer, R 3 The structural unit (B) is a methyl group. The structural unit (B) in which m is 1 to 30 can be formed by using, for example, methoxy (poly) glycol methacrylate, ethoxy (poly) glycol methacrylate, propoxy (poly) glycol methacrylate, or butoxy (poly) glycol methacrylate as monomers. For example, if methoxy polyethylene glycol methacrylate (average molar number of polyethylene glycol moieties (ethylene oxide (EO) added molar number): 9) is used as a monomer, a structural unit (B) in which m is 9 and R 3 The structural unit (B) is a methyl group. Specific examples of methoxy polyethylene glycol methacrylate include NK ester M-90G (EO addition molar number: 9), NK ester M-130G (EO addition molar number: 13), and NK ester AM-230G (EO addition molar number: 23) manufactured by Shin-Nakamura Chemical Industry Co., Ltd. The content of the structural unit (B) in the copolymer may be 0 mass % or may be 0 mass % to 95 mass %, preferably 1 mass % to 50 mass %, more preferably 2 mass % to 40 mass %, and further preferably 5 mass % to 30 mass %. <Structural unit (C)> Structural unit (C) is a structural unit represented by the following formula (3). In formula (3), R 4 represents an alkyl group having 1 to 4 carbon atoms. 4 An alkyl group having 1 to 3 carbon atoms is preferred, and an alkyl group having 1 to 2 carbon atoms is more preferred. In formula (3), n represents an integer from 0 to 30. In formula (3), when n is 0, R 4 When n is 1 to 30, especially 5 to 30, R 4 Preferred is a methyl group or an ethyl group, and more preferred is a methyl group. The structural unit (C) in which n is 0 can be formed, for example, by using an alkyl acrylate as a monomer. For example, if ethyl acrylate is used as a monomer, a structural unit (C) in which n is 0 and R 4 The structural unit is an ethyl group (C). The structural unit (C) in which n is 1 to 30 can be formed by using, for example, methoxy (poly) glycol acrylate, ethoxy (poly) glycol acrylate, propoxy (poly) glycol acrylate, or butoxy (poly) glycol acrylate as monomers. For example, if methoxy polyethylene glycol acrylate (average molar number of polyethylene glycol moieties (ethylene oxide (EO) added molar number): 9) is used as a monomer, a structural unit (C) in which n is 9 and R 4 The structural unit is a methyl group (C). Specific examples of methoxy polyethylene glycol acrylate include NK ester AM-90G (EO addition molar number: 9), NK ester AM-130G (EO addition molar number: 13), and NK ester AM-230G (EO addition molar number: 23) manufactured by Shin-Nakamura Chemical Industry Co., Ltd. The content of the structural unit (C) in the copolymer may be 0% by mass, or may be from 0% by mass to 85% by mass, preferably from 1% by mass to 60% by mass, more preferably from 1% by mass to 50% by mass, further preferably from 2% by mass to 40% by mass, and particularly preferably from 5% by mass to 30% by mass. The total content of the structural units (B) and (C) in the copolymer is preferably from 2 mass % to 85 mass %, more preferably from 3 mass % to 80 mass %, further preferably from 4 mass % to 70 mass %, particularly preferably from 10 mass % to 60 mass %. The copolymer preferably contains, as the structural unit (B) and / or the structural unit (C), a structural unit formed by using an alkyl (meth)acrylate as a monomer (i.e., one or more selected from the structural unit in which m is 0 in the formula (2) and the structural unit in which n is 0 in the formula (3)), and more preferably contains the structural unit in such a manner that the total content of the structural unit is 1% by mass or more and 85% by mass. <Other structural units> The copolymer may also have other structural units other than the above structural units. Examples of other structural units include structural units derived from monomers such as benzyl (meth)acrylate, chloromethyl (meth)acrylate, 2-chloroethyl (meth)acrylate, styrene, vinyltoluene, α-methylstyrene, acrylonitrile, methyl vinyl ketone, ethylene, propylene, and vinyl acetate, and structural units represented by the following formula (4). [Chemical 14] In formula (4), R 5 represents a hydrogen atom or a methyl group, R 6 Indicates direct bond, -CH 2- or CH 2CH 2-, R 7 represents an alkylene group having 2 to 20 carbon atoms, R 8 represents an alkyl group having 1 to 4 carbon atoms, and s represents an integer of 1 to 300. In formula (4), preferably R 7 50 mol% to 100 mol% of the alkylene groups represented are ethylene groups (-CH 2CH 2-). The copolymer may also contain structural units (A) formed by hydrolyzing structural unit (X), structural units (A 01 ), structural unit (A 02 ), structural units other than the structural unit (B) and the structural unit (C) (hereinafter also referred to as structural unit (Y)) as other structural units. The content of other structural units in the copolymer is preferably 20% by mass or less, more preferably 10% by mass or less, and further preferably 0% by mass. The weight average molecular weight (Mw) of the copolymer of the present embodiment is not particularly limited, but is usually preferably 1,000 to 1,000,000, more preferably 3,000 to 500,000, and still more preferably 5,000 to 100,000. The weight average molecular weight (Mw) of the copolymer can be determined by conversion to polyethylene glycol using gel permeation chromatography (GPC). (Method for Producing Copolymers) The copolymers according to one embodiment of the present disclosure can be produced using conventionally known methods. For example, they can be produced by solution polymerization of monomer components corresponding to the structural units in an aqueous solvent, followed by any necessary post-treatment such as hydrolysis. The aqueous solvent referred to in this specification refers to a solvent having a water content of 50% by mass or greater. The aqueous solvent may be water or a mixed solvent of an organic solvent and water that is compatible with water. Examples of the organic solvent that is compatible with water include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, t-butyl alcohol, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, diethylene glycol, acetone, and methyl ethyl ketone. The monomer components may be mixed with the aqueous solvent in batches or slowly by dropwise addition, etc. The amount of the monomer components per 100 parts by mass of the aqueous solvent is, for example, 5 to 1000 parts by mass, or 10 to 500 parts by mass. Furthermore, when polymerizing the monomer components, a polymerization initiator can be used. Examples of polymerization initiators include azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2-amidinopropane) dihydrochloride, 4,4'-azobis(4-cyanovaleric acid), 2,2'-azobis(2-methylpropionamidine); persulfates such as ammonium persulfate, sodium persulfate, and potassium persulfate; peroxides such as hydrogen peroxide, benzoyl peroxide, p-chlorobenzoyl peroxide, lauryl peroxide, and ammonium peroxide. These polymerization initiators can be used alone or in combination of two or more. The amount of the polymerization initiator varies depending on the type of the polymerization initiator and cannot be determined in general terms. Therefore, it is preferably adjusted to an amount appropriate for the type of the polymerization initiator. The method for adding the polymerization initiator is not particularly limited. Examples of the method for adding the polymerization initiator include batch loading, split loading, and continuous dripping. In addition, in order to advance the end of the polymerization reaction of the monomer component, a portion of the polymerization initiator may be added before or after the end of the operation of adding the monomer component in the reaction system. Furthermore, in order to promote the decomposition of the polymerization initiator, a suitable amount of a decomposing agent for the polymerization initiator, such as a reducing agent such as sodium bisulfite or a transition metal salt such as ferrous sulfate, may be added to the reaction system. Additionally, additives such as chain transfer agents, for example, compounds having a thiol group such as t-dodecyl mercaptan, pH buffers, and chelating agents may be added to the reaction system as needed. The amount of additive varies depending on the type of additive and cannot be determined in general. Therefore, it is preferably adjusted to an amount appropriate for the type of additive. The environment for polymerizing the monomer components is not particularly limited, but an inert gas such as nitrogen gas or argon gas is preferred from the viewpoint of improving the efficiency of the polymerization initiator. The polymerization temperature of the monomer components is not particularly limited, but is usually preferably 20° C. to 150° C., more preferably 50° C. to 95° C. The polymerization temperature may be constant during the polymerization of the monomer components, or may be changed during the polymerization reaction. The polymerization time of the monomer components is not particularly limited and may be appropriately set depending on the progress of the polymerization reaction of the monomer components, and is generally about 1 to 24 hours. The copolymer obtained in the above manner is subjected to ring-opening of the oxazoline ring, thereby obtaining the copolymer. The copolymer can also be produced by other methods. Specifically, for example, the copolymer disclosed herein can be produced by ring-opening the oxazoline ring of 2-vinyl-2-oxazoline or 2-isopropenyl-2-oxazoline, followed by polymerization. Water and / or a compound having a carboxyl group (carboxylic acid) can be used as a starting compound for the ring-opening of the oxazoline ring. The compound having a carboxyl group is a carboxylic acid having an optionally substituted aryl group or an optionally substituted alkyl group having 1 to 4 carbon atoms. Examples of substituents in the optionally substituted aryl group and the optionally substituted alkyl group having 1 to 4 carbon atoms include hydroxyl, alkoxy, acyl, alkoxycarbonyl, and carbamoyl groups. As the compound having a carboxyl group, a monocarboxylic acid having only one carboxyl group in one molecule is preferred because gelation may occur during the reaction. Among the raw material compounds, from the viewpoint of improving reactivity, water, which can be used as a reaction solvent in a large excess amount, and a carboxylic acid having an optionally substituted aryl group are preferred. Water and a carboxylic acid having an aryl group substituted with a hydroxyl group are preferred. Water and a carboxylic acid having a 2-hydroxybenzoyl group in which a hydroxyl group and a carboxyl group are adjacent are more preferred. Water alone, or water and a carboxylic acid having a 2-hydroxybenzoyl group are further preferred. The reaction medium, temperature, and time for the ring-opening of the oxazoline ring are not particularly limited, and the conditions for the copolymer can also be used. In order to promote the ring-opening reaction of the oxazoline ring, a catalyst such as an acid may also be used. (Composition Containing Copolymer and Water) A composition according to one embodiment of the present disclosure contains the above-mentioned copolymer and water. The content of the copolymer in the composition is preferably 0.01% by mass to 95% by mass, more preferably 1% by mass to 90% by mass, and even more preferably 5% by mass to 30% by mass, based on the total amount of the composition. The water content in the composition is preferably 5 mass % or more and 99.99 mass % or less, more preferably 10 mass % or more and 99 mass % or less, and still more preferably 50 mass % or more and 95 mass % or less, based on the total amount of the composition. The composition may also contain other additives. Examples of other additives include surfactants such as anionic surfactants, nonionic surfactants, cationic surfactants, and amphoteric surfactants, anti-reattachment agents such as sodium carboxymethyl cellulose for preventing the redeposition of pollutants, scale inhibitors such as benzotriazole or ethylene-thiourea, soil release agents, color migration inhibitors, softeners, alkaline substances such as carbonates, bicarbonates, and silicates, tripolyphosphates, pyrophosphates, sodium sulfate, nitrilotriacetate, ethylenediaminetetraacetate, citrates, copolymer salts of (meth)acrylic acid, acrylic acid-maleic acid copolymers, fumarates, fragrances, solubilizers, fluorescent agents, colorants, foaming agents, foam stabilizers, polishing agents, bactericides, bleaching agents, bleaching aids, proteases, lipases, cellulases, starches, Enzymes such as enzymes, dyes, solvents, chelating agents, pH adjusters, hydrophilic water-soluble resins such as polyvinyl alcohol and polyvinyl alcohol / polyethylene glycol, which are highly hydrophilic polymers with ionic properties such as hydroxyl, carboxyl, and amine groups; acrylic resins, polyester resins, epoxy resins, urethane resins, pigments, dispersants, desiccants, antioxidants, defoamers, dehydrating agents, leveling agents, anti-settling agents, drip inhibitors, algaecides, mildew inhibitors, preservatives, UV absorbers, and light stabilizers. Examples of salts used in these other additives include alkali metals such as sodium and potassium, and alkaline agents such as sodium hydroxide, ammonium, and amines. One or more of these can be used. When other additives are included, their content is preferably 0.01% by mass or more and 5% by mass or less, and more preferably 0.01% by mass or more and 1% by mass or less, based on the total amount of the composition. The pH value of the composition can be set to, for example, 1 or more and 6 or less, preferably 2 or more and 5 or less. Since the composition contains the copolymer, it can be suitably used as an additive for cleaning agents. For example, the composition can be suitably used as an additive in powder detergents for clothing, liquid detergents for clothing, detergents for hard surfaces such as glass, metal, tableware, kitchens, toilets, cars, and industrial machinery, detergents for tires or wood, and detergents for plastic films or plastic containers. (Cleaning Agent Additive) A cleaning agent additive according to one embodiment of the present disclosure includes the above-mentioned copolymer or the above-mentioned composition. Since the detergent additive contains the copolymer or the composition, it has excellent cleaning performance for oil stains. (Use of Copolymer as a Cleaning Agent Additive) The copolymer of one embodiment of the present disclosure can be used as a cleaning agent additive. Preferably, the copolymer of one embodiment of the present disclosure can be used as the cleaning agent additive. Preferred embodiments of the copolymer are as described above. (Cleaning Method Using Copolymer) A cleaning method according to one embodiment of the present disclosure is characterized by using the above-described copolymer. The cleaning method according to one embodiment of the present disclosure can preferably be used for cleaning, for example, clothing; hard surfaces such as glass and metal, tableware, kitchenware, toilets, automobiles, and industrial machinery; tires, wood; and plastic films and containers. [Examples] The present disclosure is described in more detail below with reference to Examples, but the present disclosure is not limited to these Examples. Furthermore, unless otherwise specified, "parts" means "parts by mass" and "%" means "% by mass." [Production Example 1] A flask equipped with a stirrer, a reflux cooler, a nitrogen inlet tube, and a thermometer was charged with 578 parts of ion-exchanged water and 262 parts of isopropyl alcohol, and heated to 80°C while slowly flowing nitrogen gas. A previously prepared monomer mixture containing 105 parts of methyl methacrylate, 210 parts of 2-isopropenyl-2-oxazoline, and 105 parts of methoxypolyethylene glycol acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., EO addition molar number 9 mol, trade name: NK ester AM-90G), and a polymerization initiator solution containing 21 parts of 2,2'-azobis(2-methylpropionamidine) dihydrochloride (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd., product number: V-50) as a polymerization initiator and 189 parts of ion-exchanged water were added dropwise from a dropping funnel over 2 hours to the flask. During the polymerization reaction, nitrogen gas was continuously circulated into the flask to maintain the temperature at 80°C ± 1°C. After the addition was completed, the contents of the flask were maintained at the same temperature for 5 hours and then cooled to obtain an oxazoline-containing polymer with a solids content (non-volatile content) of 30.4%. [Production Example 2] A flask equipped with a stirrer, reflux cooler, nitrogen inlet tube, thermometer, and dropping funnel was charged with 179 parts of deionized water and 1 part of V-50 (a polymerization initiator: 2,2'-azobis(2-methylpropionamidine) dihydrochloride, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.). The mixture was heated to 60°C while slowly flowing nitrogen gas. A previously prepared monomer mixture containing 1 part of ethyl acrylate, 1 part of methyl methacrylate, and 18 parts of 2-isopropenyl-2-oxazoline was added dropwise from the dropping funnel over 1 hour. During the reaction, nitrogen gas was continuously flowed, and the temperature in the flask was maintained at 60°C ± 1°C. After the addition was completed, the temperature was maintained at the same level for 9 hours, followed by cooling. This yielded an aqueous solution of an oxazoline-containing polymer having a non-volatile content of 10.5% and a pH of 7.4. [Manufacturing Example 3] In Manufacturing Example 1, except that the amount of 2-isopropenyl-2-oxazoline used was changed from 210 parts to 105 parts, and the amount of methoxypolyethylene glycol acrylate [manufactured by Shin-Nakamura Chemical Co., Ltd., EO addition molar number 9 mol, trade name: NK ester AM-90G] used was changed from 105 parts to 210 parts, an oxazoline group-containing polymer having a solid content (non-volatile content) of 30.4% was obtained in the same manner as in Manufacturing Example 1. [Example 1] After adding 30.4 parts of the solution of the oxazoline-containing polymer obtained in Preparation Example 1 to a reaction vessel, 156.4 parts of water and 13.0 parts of a 1 mol% hydrochloric acid aqueous solution were added dropwise while stirring and mixed. Next, the mixture was heated in an oil bath until the internal temperature reached 90°C, and then stirred for 5 hours to carry out a ring-opening reaction of the oxazoline-containing polymer. The mixture was then dried at 25°C under 0.01 MPa for 5 hours in a vacuum dryer to obtain a polymer (1). The obtained polymer (1) was dissolved in 189.8 parts of water to obtain an aqueous solution containing the polymer (1) with a non-volatile content of 5%. The pH value of the aqueous solution was 4.0. The polymer (1) was subjected to 1 H-NMR ( 1 H-Nuclear Magnetic Resonance, 1 H-NMR) determination and colloid titration, the results, R 1 The structural unit (A) which is a hydrogen atom is 21 mass %, and the structural unit (A 02 ) is 6 mass %, the structural unit (X) is 25 mass %, the structural unit (B) is 24 mass %, and the structural unit (C) is 24 mass %. [Example 2] After adding 29.0 parts by mass of the solution of the oxazoline-containing polymer obtained in Preparation Example 1 to a reaction vessel, 157.6 parts of water, 0.55 parts of salicylic acid and 13.0 parts of a 1 mol% hydrochloric acid aqueous solution were added dropwise while stirring and mixed. Next, heating was performed in an oil bath until the internal temperature reached 60°C, followed by stirring for 4 hours, and further heating was performed in an oil bath until the internal temperature reached 90°C, followed by stirring for 1 hour to carry out a ring-opening reaction of the oxazoline-containing polymer. The polymer (2) was then dried at 25°C under 0.01 MPa for 5 hours in a vacuum dryer to obtain a polymer (2). The obtained polymer (2) was dissolved in 189.8 parts of water to obtain an aqueous solution containing the polymer (2). The pH value of the aqueous solution was 3.2. The polymer (2) was subjected to 1 H-NMR measurement and colloid titration revealed peaks originating from aromatic rings, indicating that the reaction rate of the raw material salicylic acid was 98%, thus confirming that R 1 The structural unit (A) which is a hydrogen atom is 34% by mass, and R 1 The content of the structural unit (A) which is a 2-hydroxybenzyl group is 15% by mass, and the content of the structural unit (A) 02 ) is 8% by mass, the structural unit (B) is 22% by mass, and the structural unit (C) is 21% by mass. [Example 3] After adding 83.0 parts of the aqueous solution of the oxazoline group-containing polymer obtained in Preparation Example 2 to a reaction vessel, 105.0 parts of water and 12.0 parts of a 1 mol% hydrochloric acid aqueous solution were added dropwise while stirring and mixed. Next, the mixture was heated in an oil bath until the internal temperature reached 90°C, and then stirred for 5 hours to carry out a ring-opening reaction of the oxazoline group-containing polymer, thereby obtaining an aqueous solution containing a polymer (3) with a non-volatile content of 5%. The pH value of the aqueous solution was 4.3. The polymer (3) was subjected to 1 H-NMR measurement and colloid titration confirmed that R 1 The structural unit (A) which is a hydrogen atom is 47 mass %, and the structural unit (A 02 ) is 13% by mass, structural unit (X) is 31% by mass, structural unit (B) is 4% by mass, and structural unit (C) is 5% by mass. [Example 4] After adding 66.0 parts of the aqueous solution of the oxazoline group-containing polymer obtained in Preparation Example 2 to a reaction container, 119.6 parts of water, 2.35 parts of salicylic acid and 12.0 parts of a 1 mol% hydrochloric acid aqueous solution were added dropwise while stirring and mixed. Next, the mixture was heated in an oil bath until the internal temperature reached 60°C, and then stirred for 4 hours. The mixture was further heated in an oil bath until the internal temperature reached 90°C, and then stirred for 1 hour to carry out a ring-opening reaction of the oxazoline group-containing polymer, thereby obtaining an aqueous solution containing polymer (4) with a non-volatile content of 5%. The pH value of the aqueous solution was 3.9. The polymer (4) was subjected to 1 H-NMR measurement and colloid titration revealed peaks originating from aromatic rings, indicating that the reaction rate of the raw material salicylic acid was 98%, thus confirming that R 1 The structural unit (A) which is a hydrogen atom is 25 mass %, R 1 The content of the structural unit (A) which is a 2-hydroxybenzyl group is 58% by mass, and the content of the structural unit (A) is 58% by mass. 02 ) is 11% by mass, structural unit (B) is 3% by mass, and structural unit (C) is 3% by mass. [Example 5] In Example 1, except that 30.4 parts of the solution of the oxazoline group-containing polymer obtained in Preparation Example 3 were used instead of 30.4 parts of the solution of the oxazoline group-containing polymer obtained in Preparation Example 1, an aqueous solution containing 5% of the polymer (5) was obtained in the same manner as in Example 1. The pH value of the aqueous solution was 4.0. The polymer (5) was subjected to 1 H-NMR measurement and colloid titration showed that R 1 The structural unit (A) which is a hydrogen atom is 11 mass % of the structural unit (A 02 ) is 3 mass %, the structural unit (X) is 13 mass %, the structural unit (B) is 24 mass %, and the structural unit (C) is 49 mass %. <Weight-Average Molecular Weight Measurement Conditions (GPC)> Apparatus: HLC8320, manufactured by Tosoh Corporation Column: TSKgelα-M, TSKgelα-2500, manufactured by Tosoh Corporation Column temperature: 40°C Flow rate: 0.8 ml / min Calibration curve: Polyethylene glycol (used with GL Sciences products with Mw = 194, 410, 615, 1020, 1450, 3860, 8160, 16100, 21160, 49930, 67600, 96100, 205500, 542500, and 942000) Eluent: 200 mM sodium nitrate + 500 mM acetic acid aqueous solution / acetonitrile = 50:50 vol% <Determination of Reaction Rate of the Raw Material Compound> The reaction rate of the raw material compound (salicylic acid) was determined by measuring the amount of unreacted raw material compound in the resulting aqueous reaction solution under the following liquid chromatography (LC) measurement conditions. Measurement apparatus: Prominence UFLC manufactured by Shimadzu Corporation; Column: CAPCELL PAK ADME manufactured by Shiseido Co., Ltd.; Temperature: 40.0°C; Eluent: 10 mmol / L aqueous phosphoric acid solution / acetonitrile = 50 / 50 (volume ratio); Flow rate: 1.0 ml / min; Detector: Ultraviolet (UV) (detection wavelength: 254 nm) <NMR measurement> To confirm the synthesis of the polymer, the following measuring equipment and measuring conditions were used: 1H-NMR measurement. Specifically, 50 mg of the polymer, previously vacuum-dried at 0.01 MPa and 25°C for 5 hours, was placed in a 5 mm diameter NMR tube and dissolved in heavy water. The adjusted solution was measured under the following conditions. Measurement apparatus: Varian VNMRS 600 MHz Scan number: 16 Measurement temperature: 20°C <Colloid Titration> To confirm polymer synthesis, the amine content was quantified using the following method. 0.7 g of the polymer was added to a 100 ml beaker and dissolved in 70 g of pure water. Toluidine blue was then added as an indicator to prepare a measurement sample. The sample was then subjected to colloid titration using a 1 / 400 N potassium polyvinyl sulfate solution to quantify the amine content. <Determination of Carbon Black Dispersibility> The carbon black dispersibility of the polymers obtained in Examples 1 to 4 was determined by the following method. The results are shown in Table 1. Carbon black serves as a model for oily dirt, which is difficult to clean, and the carbon black dispersibility is an indicator of the ability to clean oily dirt. To determine the carbon black dispersibility, a buffer solution and a 0.1% aqueous solution of the polymer were first prepared. The buffer solution was prepared by adding pure water to 6.76 g of glycine, 5.26 g of sodium chloride, and 0.50 g of 48% sodium hydroxide to adjust the total amount to 60.0 g. 0.123 g of calcium chloride dihydrate and 0.056 g of magnesium chloride hexahydrate were then added, followed by pure water to adjust the total amount to 1000.0 g. The 0.1% aqueous solution of the polymer was prepared by diluting the polymers obtained in Examples 1 to 4 with an appropriate amount of water to adjust the solid content concentration to 0.1% by mass. Next, the solutions and carbon black powder were added to a 30 ml test tube in the prescribed order and amounts. The prescribed order and amounts were as follows: first, 0.03 g of carbon black powder, second, 27.0 g of buffer solution, and finally, 3.0 g of a 0.1% aqueous polymer solution. After adding the solutions and carbon black powder in this order, the test tube was capped and gently inverted up and down 60 times to stir the contents. The tube was then allowed to stand at room temperature for 4 hours. After 4 hours, the supernatant was immediately placed in a 1 cm quartz cell and its absorbance at a UV wavelength of 380 nm was measured using a spectrophotometer (UV-1800, manufactured by Shimadzu Corporation). A higher absorbance indicates well-dispersed carbon black powder. A comparative example was also used in which no 0.1% aqueous polymer solution was used. <Foamability and Foam Durability Evaluation Test> To a 15 mL sample tube (2.4 cm diameter × 5 cm height), a 50 ppm aqueous solution (0.8 mL) of the polymers obtained in Examples 1 to 4, or pure water (0.8 mL) as a comparative example, and a 312.5 ppm aqueous solution (3.2 mL) of linear alkylbenzene sulfonate (LAS) were added to prepare evaluation samples. The evaluation samples were manually shaken (30 times) for 10 seconds to create foam. Neopelex G-25 (manufactured by Kao Corporation) was used as LAS. The foam height immediately after shaking and after standing for 30 minutes were used as the foamability and foam durability, respectively, and were evaluated according to the following criteria. The results are shown in Table 1. A higher foam height immediately after shaking indicates better foaming performance. A higher foam height after standing for 30 minutes indicates better foam durability. ○: 2 cm or more and 3 cm or less △: 1 cm or more and less than 2 cm ×: 0 cm or more and less than 1 cm [Table 1] <Detergent Test> Detergent tests were conducted on the copolymers obtained in Examples 1 and 3 (polymers (1) and (3)) by the following method. The detergent test was conducted in the same manner except that no copolymer was added, and a blank was prepared for comparison. (i) 200 g of the buffer solution prepared in the carbon black dispersibility measurement was diluted to 400 g to obtain a diluted buffer solution. (ii) 0.1 g of a copolymer having a non-volatile content of 5% was diluted to 50 g using the diluted buffer solution in (i) to obtain a copolymer solution. (iii) Two pieces of cloth (0.38 g) were placed in 50 g of the copolymer solution in (ii), stirred with a stirrer for 30 minutes, and air-dried for one day to obtain treated cloth. (iv) 61.5 g of olive oil, 38 g of oleic acid, and 0.5 g of oil red were mixed to prepare a grease-contaminated liquid. 15 μL of the grease-contaminated liquid was added dropwise to the treated cloth in (iii) and allowed to stand at 40°C for 1 hour to obtain contaminated cloth. (v) Measure Emulgen 10 (Kao Corporation) into a beaker and add ion-exchanged water to 100 g to prepare a 10% surfactant solution. (vi) Place a stirrer in a 100 mL beaker, mix 50 g of the diluted buffer solution from (i) and 0.085 g of the surfactant solution from (v), and add a stain from (iv) whose Z value has been previously measured using a colorimetric analyzer (SE6000, Nippon Denshoku Industries). Stir for 10 minutes. Discard the water in the beaker and rinse once with the diluted buffer solution from (i) for 3 minutes. Then, dehydrate the cloth and air-dry it for 1 day. After air-drying, measure the Z value of the washed cloth again using a colorimetric analyzer. Calculate the wash rate using the following formula: Wash rate (Δ) = Zw - Zs. Zs represents the Z value of the cloth before washing, and Zw represents the Z value of the cloth after washing. The results of the copolymer's cleaning power test are as follows. The larger the cleaning rate, the higher the cleaning power (the cleaning effect on soiled cloth). Polymer (1): Cleaning rate (Δ) = 1.40 Polymer (3): Cleaning rate (Δ) = 1.58 Blank: Cleaning rate (Δ) = 0.27 none

Claims

1. A copolymer having: a structural unit (A) represented by formula (1) below; a structural unit (A02) represented by formula (7) below; and a structural unit (B) represented by formula (2) below and / or a structural unit (C) represented by formula (3) below, [in formula (1), R1 represents a hydrogen atom or -C(=O)-X, R2 represents a hydrogen atom or methyl; X represents a substituted aryl or a substituted alkyl group having 1 to 4 carbon atoms] [in formula (7), R2 represents a hydrogen atom or methyl] [in formula (2), R3 represents an alkyl group having 1 to 4 carbon atoms, m represents an integer from 0 to 30] [in formula (3), R4 represents an alkyl group having 1 to 4 carbon atoms, n represents an integer from 0 to 30].

2. The copolymer as described in claim 1, having structural unit (A), structural unit (A02), structural unit (B) and structural unit (C).

3. The copolymer as described in claim 1 or 2, wherein, The content of structural unit (A) in the copolymer is 5% by mass or more and 98% by mass or less; the content of structural unit (B) in the copolymer is 1% by mass or more and 50% by mass or less; and the content of structural unit (C) in the copolymer is 1% by mass or more and 60% by mass or less.

4. The copolymer as described in claim 1 or 2, wherein, R1 is selected from at least one of hydrogen atom and -C(=O)-X, where X is an ortho-hydroxyphenyl group.

5. The copolymer as described in claim 1 or 2, wherein, m is 0 and R3 is a methyl group.

6. The copolymer as described in claim 1 or 2, wherein, n is 0 and R4 is ethyl, or n is 5 to 30 and R4 is methyl.

7. The copolymer as described in claim 1 or 2, wherein, The content of structural unit (A02) in the copolymer is more than 1% by mass and less than 98% by mass.

8. A composition comprising a copolymer as described in any one of claims 1 to 7 and water.

9. An additive for cleaning agents, comprising a copolymer as described in any one of claims 1 to 7, or a composition as described in claim 8.