JP7502093B2 - Amino group-containing copolymer - Google Patents

Description

The present invention relates to an amino group-containing copolymer. More specifically, the present invention relates to an amino group-containing copolymer that is useful for detergent applications such as liquid detergents and powder detergents.

2. Description of the Related Art Detergents used for clothing have conventionally been blended with detergent builders (detergent assistants) such as zeolite, carboxymethyl cellulose, and polyethylene glycol in order to improve the cleaning effect of the detergent.
In addition to the various detergent builders mentioned above, in recent years, polymers have been blended as detergent builders in detergent compositions.
Regarding such polymers, for example, Patent Documents 1 to 5 disclose copolymers having structural units derived from a monomer having a tertiary or quaternary amino group and structural units derived from a polyalkylene glycol-containing monomer.
Furthermore, Patent Documents 6 and 7 disclose copolymers in which amino groups have been introduced by ring-opening addition of alkyleneimine to at least a portion of the carboxyl groups of a copolymer obtained by copolymerizing a monomer component essentially containing a specific unsaturated carboxylic acid monomer and/or a specific unsaturated alcohol monomer.

JP 2008-038078 A Japanese Patent No. 5224643 JP 2006-176641 A International Publication No. 2018/074334 JP 2003-40719 A Patent No. 3917857 Patent No. 3961845

In recent years, synthetic fibers such as polyester have become increasingly popular as materials for clothing and other items due to their excellent durability, quick drying, and wrinkle resistance. While polyester has the above-mentioned advantages, it has the disadvantage that it is a hydrophobic fiber and therefore has a strong adsorption power for sebum stains, making it more difficult to remove stains than cotton and other fibers. Furthermore, with the increase in dual-income households in recent years, laundry is often washed together, and laundry is left dirty for long periods of time, which is also a factor in the difficulty of removing stains. Under these circumstances, the various polymers used in conventional detergent applications do not have sufficient soil release properties that make it easier to remove stains, and there is room for improvement.

The present invention was made in consideration of the above-mentioned current situation, and aims to provide a polymer that has better soil release properties than conventional polymers.

The inventors conducted extensive research into polymers used in detergent applications and discovered that a copolymer having structural units derived from a monomer with an amino group of a specific structure and structural units derived from a specific hydrophobic monomer has better soil release properties than conventional polymers. They came to the realization that the above-mentioned problems could be successfully solved, and thus arrived at the present invention.

That is, the first invention is an amino group-containing copolymer having a structural unit (a) derived from a monomer (A) having an amino group and a structural unit (b) derived from a hydrophobic monomer (B), the monomer (A) having an amino group includes a monomer (A1) having a primary amino group, and the hydrophobic monomer (B) is an amino group-containing copolymer having a solubility parameter of a homopolymer of 13 or less.

The second invention is an amino group-containing copolymer having a structural unit (a) derived from a monomer (A) having an amino group and a structural unit (b) derived from a hydrophobic monomer (B), the monomer (A) having an amino group includes a monomer (A2) having two or more nitrogen atoms, and the hydrophobic monomer (B) has a solubility parameter of 13 or less as a homopolymer.

The monomer (A2) having two or more nitrogen atoms preferably has a secondary amino group and/or a tertiary amino group.

The monomer (A2) having two or more nitrogen atoms preferably has a structure in which some or all of the hydrogen atoms of the amino group are substituted with a group having an alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms.

The copolymer preferably further contains a structural unit (c) derived from a monomer (C) having at least one hydrophilic group selected from the group consisting of a hydroxyl group, an oxyalkylene group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, an amino group, and salts thereof.

The structural unit (a) preferably has a (poly)alkyleneimine structure.

The amino group-containing copolymer of the first invention is represented by the following formula (1-1);

(In the formula, R ¹ , R ² and R ³ are the same or different and represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. R ⁴ and R ⁵ are the same or different and represent a hydrogen atom, a (poly)alkyleneamino group which may have a substituent, or an alkyl group having 1 to 30 carbon atoms. However, when R ⁴ and R ⁵ are not both hydrogen atoms, at least one of R ⁴ and R ⁵ is a (poly)alkyleneamino group which may have a substituent and has a primary amino group. A ¹ are the same or different and represent an alkylene group having 2 to 18 carbon atoms. x1 is a number from 0 to 4. y1 is 0 or 1.)

The amino group-containing copolymer of the second aspect of the present invention is represented by the following formula (1-2):

(In the formula, R ¹ , R ² and R ³ are the same or different and represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. R ^4' and R ^5' are the same or different and represent a hydrogen atom, a (poly)alkyleneamino group which may have a substituent, or an alkyl group having 1 to 30 carbon atoms, with the proviso that at least one of R ^4' and R ^5' is a (poly)alkyleneamino group which may have a substituent. A ¹ are the same or different and represent an alkylene group having 2 to 18 carbon atoms. x1 is a number from 0 to 4. y1 is 0 or 1.)

The structural unit (c) is represented by the following formula (2);

(In the formula, R ⁶ , R ⁷ and R ⁸ are the same or different and represent a hydrogen atom, or at least one hydrophilic group selected from the group consisting of a hydroxyl group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, a secondary or tertiary amino group, and salts thereof, or an alkyl group having 1 to 3 carbon atoms which may have the hydrophilic group. Z represents a hydrogen atom, a methyl group, or a hydrocarbon group having 2 to 30 carbon atoms and having at least one hydrophilic group selected from the group consisting of a hydroxyl group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, an amino group, and salts thereof. A ² are the same or different and represent an alkylene group which may have at least one hydrophilic group selected from the group consisting of a hydroxyl group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, a secondary or tertiary amino group, and salts thereof. n represents the average number of moles of (AO) added and is a number from 0 to 200. x2 and w are the same or different and represent a number from 0 to 4. y2 and v are the same or different and represent 0 or 1.

The amino group-containing copolymer preferably has a ratio of structural unit (a) of 1 to 50% by mass relative to 100% by mass of all structural units.

The amino group-containing copolymer preferably has a ratio of structural unit (b) of 5 to 50% by mass relative to 100% by mass of all structural units.

The amino group-containing copolymer preferably has a ratio of structural unit (c) of 0 to 95% by mass relative to 100% by mass of all structural units.

The present invention is also a detergent additive containing the above amino group-containing copolymer.

The present invention also relates to a detergent composition containing the above-mentioned amino group-containing copolymer and a detergent additive other than the copolymer.

The amino group-containing copolymer of the present invention has the above-mentioned composition and has excellent soil release properties, so it can be suitably used in detergents for textile products such as polyester.

The present invention will be described in detail below. In this specification, when the term "the present invention" is used, it means matters common to the first and second inventions.
The preferred embodiments of the present invention will be described in detail below, but the present invention is not limited to the following description, and can be modified as appropriate within the scope of the present invention. In addition, a combination of two or more of the individual preferred embodiments of the present invention described below also falls within the preferred embodiments of the present invention.

The amino group-containing copolymer of the present invention has a structural unit (a) derived from a monomer (A) having an amino group and a structural unit (b) derived from a hydrophobic monomer (B) having a homopolymer solubility parameter of 13 or less.
By washing clothes such as polyester with a detergent containing the amino group-containing copolymer of the present invention, the hydrophobic group in the structural unit (b) is adsorbed to hydrophobic fibers such as polyester, and the amino group-containing copolymer can maintain the state of being adsorbed to the fiber even after washing. Since dirt adheres to such clothes from above the adsorbed amino group-containing copolymer, the dirt is sufficiently prevented from penetrating deep into the fiber, and the dirt is easily removed together with the amino group-containing copolymer by the action of the surfactant, which is considered to have excellent soil release properties. In addition, the first amino group-containing copolymer of the present invention has a primary amino group, and the second amino group-containing copolymer of the present invention has two or more nitrogen atoms in the monomer (A), which can improve the affinity with dirt, and this is also considered to make it easier to remove the dirt. Furthermore, the amino group-containing copolymer of the present invention interacts with the surfactant to act on the dirt attached to the cloth and lift the dirt. Since the dirt particles to which the polymer is attached have good dispersion stability, it can be prevented from adhering to the cloth again. Due to these actions, the amino group-containing copolymer of the present invention has excellent cleaning power. Furthermore, by repeatedly washing the amino group-containing copolymer of the present invention, the amino group-containing copolymer is fixed to the clothing, etc., thereby exhibiting excellent stain resistance and further exhibiting sufficient soil release properties.

The amino group-containing copolymer of the present invention preferably has a content of structural unit (a) of 1 to 50% by mass relative to 100% by mass of all structural units. This provides a more suitable range for the balance between hydrophilicity and hydrophobicity of the amino group-containing copolymer, resulting in better soil releasability. More preferably, it is 2 to 45% by mass, even more preferably 3 to 40% by mass, particularly preferably 4 to 35% by mass, and most preferably 5 to 30% by mass.

The amino group-containing copolymer of the first invention preferably has a content of structural unit (a1) of 1 to 50% by mass relative to 100% by mass of all structural units. This brings the balance between hydrophilicity and hydrophobicity of the amino group-containing copolymer into a more suitable range, resulting in better soil releasability. More preferably, it is 2 to 45% by mass, even more preferably 3 to 40% by mass, particularly preferably 4 to 35% by mass, and most preferably 5 to 30% by mass.

The amino group-containing copolymer of the second invention preferably has a content of structural unit (a2) of 1 to 50% by mass relative to 100% by mass of all structural units. This brings the balance between hydrophilicity and hydrophobicity of the amino group-containing copolymer into a more suitable range, resulting in better soil releasability. More preferably, it is 2 to 45% by mass, even more preferably 3 to 40% by mass, particularly preferably 4 to 35% by mass, and most preferably 5 to 30% by mass.

The amino group-containing copolymer of the first aspect of the present invention only needs to have the structural unit (a1), but may further have the structural unit (a2).
The amino group-containing copolymer of the second aspect of the present invention only needs to have the structural unit (a2), but may further have the structural unit (a1).
The structural unit (a2) in the amino group-containing copolymer of the first invention and the structural unit (a1) in the amino group-containing copolymer of the second invention are not particularly limited, but each is preferably 0 to 20% by mass, more preferably 0 to 10% by mass, still more preferably 0 to 5% by mass, and particularly preferably 0 to 1% by mass, based on 100% by mass of all structural units.

The amino group-containing copolymer of the present invention preferably has a content ratio of structural unit (b) of 5 to 50% by mass relative to 100% by mass of all structural units. This brings the balance between hydrophilicity and hydrophobicity of the amino group-containing copolymer into a more suitable range, resulting in better soil releasability. It is more preferably 10 to 45% by mass, even more preferably 15 to 40% by mass, and particularly preferably 20 to 35% by mass.

The amino group-containing copolymer of the present invention preferably contains structural unit (c), and the content ratio thereof is preferably 0 to 95 mass% relative to 100 mass% of all structural units. This brings the balance between hydrophilicity and hydrophobicity of the amino group-containing copolymer into a more suitable range, resulting in better soil releasability. It is more preferably 15 to 90 mass%, even more preferably 30 to 85 mass%, and particularly preferably 45 to 75 mass%.

The amino group-containing copolymer of the present invention may contain structural units (c1) derived from a (poly)alkylene glycol monomer (C1) as the hydrophilic group-containing monomer (C), and the content ratio thereof is preferably 0 to 95 mass% relative to 100 mass% of all structural units. This brings the balance between hydrophilicity and hydrophobicity of the amino group-containing copolymer into a more suitable range, resulting in better soil releasability. It is more preferably 15 to 90 mass%, even more preferably 30 to 85 mass%, and particularly preferably 45 to 75 mass%.

The amino group-containing copolymer of the present invention may contain structural units (c2) derived from unsaturated monocarboxylic acid (C2) as hydrophilic group-containing monomer (C), and the content ratio is preferably 0 to 50 mass% relative to 100 mass% of all structural units. This brings the balance between hydrophilicity and hydrophobicity of the amino group-containing copolymer into a more suitable range, resulting in better soil releasability. It is more preferably 0 to 40 mass%, even more preferably 0 to 30 mass%, and particularly preferably 0 to 15 mass%.

The amino group-containing copolymer of the present invention may contain a structural unit (c3) derived from a hydrophilic group-containing monomer (C3) other than a (poly)alkylene glycol monomer (C1) or an unsaturated monocarboxylic acid (C2) as the hydrophilic group-containing monomer (C), and the content ratio thereof is preferably 0 to 30 mass% relative to 100 mass% of all structural units. It is more preferably 0 to 25 mass%, even more preferably 0 to 20 mass%, and particularly preferably 0 to 15 mass%.

The amino group-containing copolymer of the present invention may have a structural unit (e) other than the above structural units (a), (b) and (c).
The proportion of the structural unit (e) in the copolymer is preferably 0 to 30% by mass relative to 100% by mass of all structural units.
It is more preferably 0 to 20% by mass, further preferably 0 to 10% by mass, and most preferably 0% by mass.

The amino group-containing copolymer of the present invention preferably has a weight average molecular weight of 3,000 to 300,000. This allows the amino group-containing copolymer of the present invention to have excellent compatibility with surfactants. The weight average molecular weight is preferably 5,000 to 250,000, more preferably 7,000 to 200,000, and even more preferably 10,000 to 100,000.
The weight average molecular weight can be measured by the method described in the Examples.

<Primary Amino Group-Containing Monomer (A1)>
In the first aspect of the present invention, the monomer (A) having an amino group includes a monomer (A1) having a primary amino group (hereinafter also referred to as a primary amino group-containing monomer (A1) or a monomer (A1). The primary amino group-containing monomer (A1) is not particularly limited as long as it has a primary amino group, but it is preferable that the primary amino group-containing monomer (A1) has a (poly)alkyleneimine structure.

The amino group-containing copolymer of the first invention preferably has a structural unit (a1) represented by the above formula (1-1). The monomer forming the structural unit (a1) represented by the above formula (1-1) is the following formula (3-1);

(In the formula, R ¹ , R ² and R ³ are the same or different and represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. R ⁴ and R ⁵ are the same or different and represent a hydrogen atom, a (poly)alkyleneamino group which may have a substituent, or an alkyl group having 1 to 30 carbon atoms. However, when R ⁴ and R ⁵ are not both hydrogen atoms, at least one of R ⁴ and R ⁵ is a (poly)alkyleneamino group which may have a substituent and has a primary amino group. A ¹ are the same or different and represent an alkylene group having 2 to 18 carbon atoms. x1 represents a number from 0 to 4. y1 represents 0 or 1.), but the structural unit (a) is not limited to those obtained from a monomer represented by formula (3-1).

The above R ¹ , R ² and R ³ are the same or different and each is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. The above alkyl group is preferably a methyl group, an ethyl group or a propyl group, and has 1 or 2 carbon atoms, more preferably a methyl group or an ethyl group, and further preferably a methyl group.
R ¹ , R ² and R ³ are the same or different and are preferably a hydrogen atom or a methyl group. More preferably, R ¹ and R ² are hydrogen atoms and R ³ is a hydrogen atom or a methyl group. Even more preferably, R ¹ and R ² are hydrogen atoms and R ³ is a methyl group.

The above ^R4 and ^R5 are the same or different and each represents a hydrogen atom, a (poly)alkyleneamino group which may have a substituent, or an alkyl group having 1 to 30 carbon atoms. When neither ^R4 nor ^R5 is a hydrogen atom, at least one of ^R4 and ^R5 is a (poly)alkyleneamino group which may have a substituent and has a primary amino group.

The number of repeats of the alkyleneamino groups in ^R4 and ^R5 is not particularly limited, but the total number of alkyleneamino groups in ^R4 and ^R5 is preferably 0 to 9. More preferably, it is 0 to 7, even more preferably 0 to 4, particularly preferably 1 to 2, and most preferably 1. In other words, an embodiment in which one of ^R4 and ^R5 is an alkyleneamino group and the other is a hydrogen atom is one of the preferred embodiments of the present invention.

The substituents that the (poly)alkyleneamino group may have are not particularly limited, but include hydrocarbon groups having 1 to 30 carbon atoms, hydroxyl groups, oxyalkylene groups, carboxyl groups, sulfonic acid groups, phosphoric acid groups, and salt groups thereof.

A ¹ is the same or different and represents an alkylene group having 2 to 18 carbon atoms. The number of carbon atoms is preferably 2 to 8, more preferably 2 to 4, even more preferably 2 to 3, and most preferably 2.
The preferred ranges of the carbon numbers of the alkylene groups in the alkyleneamino groups of ^R4 and ^R5 are also the same.

The above x1 represents a number from 0 to 4, and y1 represents 0 or 1.
x1 is preferably 0 to 3, more preferably 0 to 2, and further preferably 0 or 1.
As the combination of (x1, y1), (0,1), (1,0), and (2,0) are preferable, (0,1) and (2,0) are more preferable, and (0,1) is the most preferable.

Specific examples of the primary amino group-containing monomer (A1) include 2-aminoethyl (meth)acrylate, an alkyleneimine adduct of (meth)acrylic acid, (meth)allylamine, vinylamine, vinylaniline, etc. Among these, 2-aminoethyl (meth)acrylate and an alkyleneimine adduct of (meth)acrylic acid are preferred.
The average number of moles of the alkyleneimine adduct in the alkyleneimine adduct of (meth)acrylic acid is not particularly limited, but is preferably 1 to 10. It is more preferably 1 to 8, even more preferably 1 to 5, and particularly preferably 1 to 3.

<Amino Group-Containing Monomer (A2) Having Two or More Nitrogen Atoms>
In the second invention, the monomer (A) having an amino group includes a monomer (A2) having two or more nitrogen atoms (hereinafter also referred to as an amino group-containing monomer (A2) having two or more nitrogen atoms or monomer (A2). The monomer (A2) has an amino group and is not particularly limited as long as it has two or more nitrogen atoms, but it is preferable that the monomer (A2) has two or more amino groups.

The amino group contained in the monomer (A2) may be any of primary, secondary and tertiary amino groups, but the monomer (A2) preferably contains a secondary amino group and/or a tertiary amino group, which provides the second copolymer of the present invention with better soil releasability.
The monomer (A2) may have a primary amino group, and an embodiment having a secondary amino group and/or a tertiary amino group and a primary amino group is one of the preferred embodiments of the present invention.
The monomer (A2) may have only a secondary amino group and/or a tertiary amino group, and such an embodiment is also one of the preferred embodiments of the present invention.

The monomer (A2) may have a structure in which some or all of the hydrogen atoms of the amino group are substituted with a group having an alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms.
The alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and even more preferably 1 to 10 carbon atoms.
Specific examples of the alkyl group include a methyl group and specific examples of the alkyl group in R ¹² of the hydrophobic monomer (B) described below.
The aryl group preferably has 6 to 20 carbon atoms, more preferably 6 to 15 carbon atoms, and even more preferably 6 to 10 carbon atoms.
Specific examples of the aryl group include the specific examples of the aryl group in R ¹² of the hydrophobic monomer (B) described below.

The monomer (A2) preferably has a (poly)alkyleneimine structure.
The amino group-containing copolymer of the second aspect of the present invention preferably has the structural unit (a2) represented by the above formula (1-2).
Examples of the monomer that forms the structural unit (a2) represented by the above formula (1-2) include a monomer represented by the following formula (3-2):

(In the formula, R ¹ , R ² and R ³ are the same or different and represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. R ^4' and R ^5' are the same or different and represent a hydrogen atom, a (poly)alkyleneamino group which may have a substituent, or an alkyl group having 1 to 30 carbon atoms, with the proviso that at least one of R ^4' and R ^5' is a (poly)alkyleneamino group which may have a substituent. A ¹ are the same or different and represent an alkylene group having 2 to 18 carbon atoms. x1 is a number from 0 to 4. y1 is 0 or 1.), but the structural unit (a2) is not limited to those obtained from a monomer represented by formula (3-2).

R ¹ , R ² , R ³ , A ¹ , x1 and y1 in the above formula (3-2) are the same as those in the above formula (3-1).
R ^4' and R ^5' are the same or different and represent a hydrogen atom, a (poly)alkyleneamino group which may have a substituent, or an alkyl group having 1 to 30 carbon atoms. At least one of R ^4' and R ^5' is a (poly)alkyleneamino group which may have a substituent, and specific examples thereof are the same as R ⁴ and R ⁵ in formula (3-1).

The number of repeats of the alkyleneamino groups in R ^4' and R ^5' is preferably 1 to 9 in total, including the alkyleneamino groups in R ^4' and R ^5' . It is more preferably 1 to 7, even more preferably 1 to 4, particularly preferably 1 to 2, and most preferably 1. In other words, an embodiment in which one of R ^4' and R ^5' is an alkyleneamino group and the other is a hydrogen atom is one of the preferred embodiments of the present invention.

In the above monomer (A2), for example, when R ^4' is an alkyleneamino group having 1 or 2 repeating units, it can be represented by -A ¹ NR ^4'' ₂ or -A ¹ NR ^4'' -A ¹ NR ^4'' ₂ (wherein A ¹ is the same or different and represents an alkylene group having 2 to 18 carbon atoms, and ^{R 4''} is the same or different and represents a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, or an aryl group having 6 to 30 carbon atoms).
The preferred ranges and specific examples of the carbon numbers of the alkyl group and aryl group in R ^4″ are as described above.

<Hydrophobic Monomer (B)>
The hydrophobic monomer (B) has a solubility parameter of 13 or less in a homopolymer obtained by homopolymerization. Even if the solubility parameter is 13 or less, if the monomer has an amino group, it is classified as an amino group-containing monomer (A).
The solubility parameter is a value calculated by the method described in pp. 147-154 of "POLYMER ENGINEERING AND SCIENCE" (1974, Vol. 14, No. 2).
The method is outlined below. The solubility parameter (δ) (cal/cm ³ ) ^1/2 of a homopolymer is calculated by the following calculation method based on the evaporation energy (Δei) and molar volume (Δvi) of the structural units forming the polymer.
δ = (Δei/Δvi) ^1/2 (cal/cm ³ ) ^1/2

If the solubility parameter for the homopolymer obtained by polymerizing a hydrophobic monomer alone is 13 or less, the hydrophobicity of the copolymer of the present invention will be sufficient and the copolymer will have excellent adsorption properties to hydrophobic fibers. The solubility parameter is preferably 12 or less, more preferably 11 or less. The solubility parameter is usually 5 or more.

The hydrophobic monomer is not particularly limited as long as the solubility parameter of the homopolymer is 13 or less, but is preferably a monomer having an ethylenically unsaturated group and a hydrocarbon group having 1 to 30 carbon atoms. The number of carbon atoms in the hydrocarbon group is preferably 2 to 22, more preferably 3 to 16, and even more preferably 4 to 8.
Examples of the hydrophobic monomer include esters of unsaturated carboxylic acids such as (meth)acrylic acid and alcohols having 1 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.

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 group thereof, and examples thereof include halogen atoms.
The alcohol preferably has 2 to 22 carbon atoms, more preferably 3 to 16 carbon atoms, and further preferably 4 to 8 carbon atoms.
Preferable examples of the alcohol having 1 to 30 carbon atoms include alkyl alcohols having 1 to 30 carbon atoms and aryl alcohols having 6 to 30 carbon atoms.

The above-mentioned alkyl alcohols having 1 to 30 carbon atoms include methanol, 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.

Preferred examples of the aryl alcohol having 6 to 30 carbon atoms include 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-hydroxymethyl-naphthalene, 1-hydroxyethyl-naphthalene, 2-hydroxymethyl-naphthalene, 2-hydroxyethyl-naphthalene, etc.

The hydrophobic monomer (B) is preferably represented by the following formula (4);

(wherein R ⁹ , R ¹⁰ and R ¹¹ are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms; and ^{R 12} represents a hydrocarbon group having 1 to 30 carbon atoms).
That is, the amino group-containing copolymer of the present invention is represented by the following formula (5):

(wherein R ⁹ , R ¹⁰ , R ¹¹ and R ¹² are the same as in formula (4)).
In addition, when the amino group-containing copolymer of the present invention has a structural unit represented by the above formula (5), the structural unit may be obtained by polymerization using a compound represented by the above formula (4) or may be obtained by other methods.

The alkyl group in the above R ⁹ , R ¹⁰ and R ¹¹ is preferably a methyl group, an ethyl group or a propyl group, more preferably a methyl group or an ethyl group, and further preferably a methyl group.
R ⁹ , R ¹⁰ and R ¹¹ are the same or different and each is preferably a hydrogen atom or a methyl group, more preferably R ⁹ and R ¹⁰ are hydrogen atoms and R ¹¹ is a hydrogen atom or a methyl group.

The number of carbon atoms in the hydrocarbon group is preferably 1 to 22. More preferably, it is 2 to 16, even more preferably 2 to 12, particularly preferably 4 to 12, and most preferably 4 to 8.

The hydrocarbon group in R ¹² is not particularly limited, and examples thereof include chain hydrocarbon groups such as alkyl groups, alkenyl groups, and alkynyl groups, and cyclic hydrocarbon groups such as aryl groups, cycloalkyl groups, and cycloalkenyl groups. The hydrocarbon group may have a branch, and the number of carbon atoms in the hydrocarbon group when it has a branch means the total number of carbon atoms in the main chain and the branched chain.

The alkyl group for R ¹² preferably has 2 to 22 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms, and most preferably 4 to 8 carbon atoms.
The aryl group in R ¹² preferably has 6 to 12 carbon atoms, more preferably 6 to 10 carbon atoms, and particularly preferably 6 to 8 carbon atoms.

Examples of the alkyl group in R ¹² include an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a hexyl group, a heptyl group, a 2-ethylhexyl group, an octyl group, a nonyl group, a decyl group, a dodecyl group, a stearyl group, and an icosyl group.
Examples of the alkenyl group include an allyl group, a 1-butenyl group, a 2-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, a nonenyl group, a decenyl group, a dodecenyl group, an octadecenyl group, and an icosenyl group.
Examples of the alkynyl group include 1-propynyl, 2-propynyl, butynyl, pentynyl, hexynyl, heptynyl, octynyl, nonynyl, decynyl, dodecynyl, octadecynyl, and icosynyl groups.

Examples of the aryl group in R ¹² include a phenyl group, a benzyl group, a methylphenyl group, a 1-methoxy-4-methylphenyl group, an ethylphenyl group, a propylphenyl group, a butylphenyl group, a butylmethylphenyl group, a dimethylphenyl group, a diethylphenyl group, a dibutylphenyl group, a 2-(2-methylphenyl)ethyl group, a 2-(3-methylphenyl)ethyl group, a 2-(4-methylphenyl)ethyl group, a 2-(4-propylphenyl)ethyl group, a biphenyl group, a biphenylmethyl group, a biphenylethyl group, a naphthyl group, a naphthylmethyl group, and a naphthylethyl group.

Examples of the cycloalkyl group in R ¹² include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group.
Examples of the cycloalkenyl group include a cyclopropenyl group, a cyclobutenyl group, a cyclopentenyl group, and a cyclohexenyl group.

The hydrocarbon group for R ¹² is preferably an alkyl group or an aryl group, more preferably an aryl group.
The hydrophobic monomer (B) is preferably an alkyl(meth)acrylate or an aryl(meth)acrylate, more preferably an aryl(meth)acrylate.

Examples of the alkyl (meth)acrylates 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.

The above aryl (meth)acrylates include, for example, phenyl (meth)acrylate, benzyl (meth)acrylate, 2-ethylphenyl (meth)acrylate, propylphenyl (meth)acrylate, butylphenyl (meth)acrylate, pentylphenyl (meth)acrylate, hexylphenyl (meth)acrylate, butylmethylphenyl (meth)acrylate, dimethylphenyl (meth)acrylate, diethylphenyl (meth)acrylate, dibutylphenyl (meth)acrylate, 2-phenylethyl (meth)acrylate, 4-methylphenyl (meth)acrylate, tert-butylphenyl (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.

<Hydrophilic Group-Containing Monomer (C)>
The hydrophilic group-containing monomer (C) has at least one hydrophilic group selected from the group consisting of a hydroxyl group, an oxyalkylene group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, a secondary or tertiary amino group, and salts thereof, and is a monomer different from the monomer (A) having an amino group.
Examples of salts of the hydrophilic groups include monovalent metal salts such as alkali metals (eg, sodium, potassium, etc.); divalent metal salts such as alkaline earth metals (eg, magnesium, calcium, etc.); ammonium salts; and organic amine salts.
The hydrophilic group is preferably a hydroxyl group or an oxyalkylene group.
The hydrophilic group-containing monomer (C) may have a plurality of hydrophilic groups, which may be the same or different. For example, a form having two or more hydroxyl groups or a form having a hydroxyl group and an oxyalkylene group is one of the preferred embodiments of the present invention.

The hydrophilic group-containing monomer (C) is represented by the following formula (6);

(In the formula, R ⁶ , R ⁷ and R ⁸ are the same or different and represent a hydrogen atom, or at least one hydrophilic group selected from the group consisting of a hydroxyl group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, a secondary or tertiary amino group, and salts thereof, or an alkyl group having 1 to 3 carbon atoms which may have the hydrophilic group. Z represents a hydrogen atom, a methyl group, or a hydrocarbon group having 2 to 30 carbon atoms and having at least one hydrophilic group selected from the group consisting of a hydroxyl group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, an amino group, and salts thereof. A ² are the same or different and represent an alkylene group which may have at least one hydrophilic group selected from the group consisting of a hydroxyl group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, a secondary or tertiary amino group, and salts thereof. n represents the average number of moles of (AO) added and is a number from 0 to 200. x2 and w are the same or different and represent a number from 0 to 4. y2 and v are the same or different and represent 0 or 1.

Salts of the above hydrophilic groups include monovalent metal salts of alkali metals such as sodium and potassium; divalent metal salts of alkaline earth metals such as magnesium and calcium; ammonium salts; organic amine salts, etc.

The hydrophilic group is preferably a hydroxyl group or an oxyalkylene group.
The hydrophilic group-containing monomer (C) may have a plurality of hydrophilic groups, which may be the same or different. For example, a form having two or more hydroxyl groups or a form having a hydroxyl group and an oxyalkylene group is one of the preferred embodiments of the present invention.

The above R ⁶ , R ⁷ and R ⁸ are the same or different and each represents a hydrogen atom, or at least one hydrophilic group selected from the group consisting of a hydroxyl group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, an amino group and salt groups thereof, or an alkyl group having 1 to 3 carbon atoms which may have the hydrophilic group.
The alkyl group is preferably a methyl group, an ethyl group, or a propyl group, and is 1 or 2, more preferably a methyl group or an ethyl group, and further preferably a methyl group.
R ⁶ , R ⁷ and R ⁸ are the same or different and are preferably a hydrogen atom or a methyl group. More preferably, R ⁶ and R ⁷ are hydrogen atoms and R ⁸ is a hydrogen atom or a methyl group. Even more preferably, R ⁶ and R ⁷ are hydrogen atoms and R ⁸ is a methyl group.

The above Z represents a hydrogen atom, a methyl group, or a hydrocarbon group having 2 to 30 carbon atoms and having at least one hydrophilic group selected from the group consisting of a hydroxyl group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, a secondary or tertiary amino group, and salts thereof.
The above-mentioned hydrocarbon group is not particularly limited, and examples thereof include chain-like hydrocarbon groups such as alkyl groups, alkenyl groups, alkynyl groups, etc., and cyclic hydrocarbon groups such as aryl groups, cycloalkyl groups, cycloalkenyl groups, etc. The above-mentioned hydrocarbon group may have a branch, and when the hydrocarbon group has a branch, the number of carbon atoms means the total number of carbon atoms in the main chain and the branched chains.
Examples of the alkyl group include an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a hexyl group, a heptyl group, a 2-ethylhexyl group, an octyl group, a nonyl group, a decyl group, a dodecyl group, a stearyl group, and an icosyl group.
Examples of the alkenyl group include vinyl, allyl, 1-butenyl, 2-butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, dodecenyl, octadecenyl, and icosenyl groups.
Examples of the alkynyl group include ethynyl, 1-propynyl, 2-propynyl, butynyl, pentynyl, hexynyl, heptynyl, octynyl, nonynyl, decynyl, dodecynyl, octadecynyl, and icosynyl groups.

Examples of the aryl group include a phenyl group, a benzyl group, a methylphenyl group, a 1-methoxy-4-methylphenyl group, an ethylphenyl group, a propylphenyl group, a butylphenyl group, a butylmethylphenyl group, a dimethylphenyl group, a diethylphenyl group, a dibutylphenyl group, a biphenyl group, a biphenylmethyl group, a biphenylethyl group, a naphthyl group, a naphthylmethyl group, and a naphthylethyl group.

Examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group.
Examples of the cycloalkenyl group include a cyclopropenyl group, a cyclobutenyl group, a cyclopentenyl group, and a cyclohexenyl group.
The above-mentioned hydrocarbon group is preferably an alkyl group or an alkenyl group, and more preferably an alkyl group.

The number of carbon atoms in the hydrocarbon group is preferably 2 to 20, more preferably 2 to 15, even more preferably 2 to 10, and particularly preferably 2 to 5.

Preferably, Z is a hydrogen atom or a methyl group.

The above ^A2s are the same or different and represent alkylene groups which may have at least one hydrophilic group selected from the group consisting of a hydroxyl group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, a secondary or tertiary amino group, and salts thereof, which means that the n oxyalkylene groups of AO present in the polyalkylene glycol may all be the same or different.
The alkylene group represented by A preferably has 2 to 18 carbon atoms, and more preferably has 2 to 4 carbon atoms.

The oxyalkylene group represented by A ² O is, for example, a group formed by an addition reaction of an alkylene oxide and a group having a structure in which the above-mentioned hydrophilic group is added to the alkylene oxide, and examples of such alkylene oxide include ethylene oxide, propylene oxide, butylene oxide, isobutylene oxide, 1-butene oxide, 2-butene oxide, styrene oxide, and alkylene oxides having 2 to 18 carbon atoms. 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.
The oxyalkylene group represented by A ² O in the formulas (2) and (6) is not limited to the group formed by the addition reaction of an alkylene oxide.

When the polyalkylene glycol is an adduct of any two or more types of alkylene oxide selected from ethylene oxide, propylene oxide, butylene oxide, styrene oxide, etc., it may be in any form such as random addition, block addition, or alternating addition. In order to ensure a balance between hydrophilicity and hydrophobicity, it is preferable that the oxyalkylene group in the polyalkylene glycol has an oxyethylene group as an essential component, more preferably 50 mol % or more of oxyethylene groups, and even more preferably 90 mol % or more of oxyethylene groups.

The above n represents the average number of moles of (A ² O) added and is a number from 0 to 200. It is preferably from 1 to 180, more preferably from 2 to 150, more preferably from 10 to 100, even more preferably from 15 to 80, and particularly preferably from 20 to 50.
When Z is a methyl group, n is preferably 10 or more.
When n is 1, A ¹ is preferably an alkylene group having a hydroxyl group.

The above x2 represents a number from 0 to 4, and y2 represents 0 or 1.
x2 is preferably 0 to 3, more preferably 0 to 2, and further preferably 0 or 1.
As the combination of (x2, y2), (0,1), (1,0) and (2,0) are preferable, (0,1) and (2,0) are more preferable, and (0,1) is the most preferable.

The above v represents 0 or 1, and w represents a number from 0 to 4.
It is preferred that v is 0.
w is preferably 0 to 3, more preferably 0 to 2, further preferably 0 or 1, and most preferably 0.

Specific examples of the hydrophilic group-containing monomer (C) include polyalkylene glycol mono(meth)acrylates such as (poly)ethylene glycol mono(meth)acrylate and (poly)propylene glycol mono(meth)acrylate; alkoxy polyalkylene glycol mono(meth)acrylates such as methoxy(poly)ethylene glycol mono(meth)acrylate and methoxy(poly)propylene glycol mono(meth)acrylate; vinyl alcohol, (meth)allyl alcohol, 3-methyl-3-buten-1-ol (isoprenol), 3-methyl-2-buten-1-ol, 2-methyl-3-buten-2-ol, 2-methyl-2-buten-1-ol, 2-methyl-3-buten- Examples of suitable monomers include (poly)alkylene glycol monomers such as compounds in which 10 to 100 moles of alkylene oxide are added to any one of 1-ols; hydroxyl-containing (meth)acrylates such as glycerol mono(meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; unsaturated monocarboxylic acids such as (meth)acrylic acid, crotonic acid, α-allyloxyacrylic acid, and salts thereof; and unsaturated dicarboxylic acids such as maleic acid, itaconic acid, mesaconic acid, citraconic acid, fumaric acid, and salts thereof and anhydrides thereof. Among these, (poly)alkylene glycol monomers, hydroxyl-containing (meth)acrylates, and unsaturated monocarboxylic acids are preferred.

The amino group-containing copolymer of the present invention may have a structural unit (e) derived from a monomer (E) other than the amino group-containing monomer (A), the hydrophobic monomer (B), and the hydrophilic group-containing monomer (C).
The monomer (E) is not particularly limited as long as it does not have a hydroxyl group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, an amino group, or a salt group thereof, and the solubility parameter of the homopolymer is greater than 13, or does not have a hydroxyl group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, an amino group, or a salt group thereof. Examples of the monomer (E) include olefin monomers having 2 to 4 carbon atoms such as ethylene and propylene, vinyl halides such as vinyl chloride, methyl vinyl ether, ethyl vinyl ether, and acrylonitrile.

<Method of producing amino group-containing copolymer>
The production of the amino group-containing copolymer of the present invention is not particularly limited, but can be produced by polymerizing the monomer components, and specific examples and preferred examples of the monomer components and the preferred ratio of each monomer are as described above.
The method for producing the copolymer preferably includes a step of polymerizing a monomer component including an amino group-containing monomer (A) or a precursor thereof and a hydrophobic monomer (B) (hereinafter, also referred to as a "polymerization step"). Such a method for producing the copolymer also constitutes one aspect of the present invention.

In the above polymerization step, polymerization may be carried out using a precursor of the amino group-containing monomer (A), and after the polymerization step, an amine compound may be reacted to produce the polyamino group-containing monomer (A).
The precursor of the amino group-containing monomer (A) is not particularly limited as long as it can react with an amine compound, but it is preferable that it has an ethylenically unsaturated bond and a functional group reactive with an amine compound.Preferably, the functional group includes a carboxyl group, an epoxy group, a hydroxyl group, etc., and is preferably a carboxyl group.
The precursor of the amino group-containing monomer (A) is preferably the above-mentioned unsaturated monocarboxylic acid monomer, more preferably (meth)acrylic acid.

The method for initiating polymerization of the monomer components in the polymerization step is not particularly limited, and examples thereof include a method of adding a polymerization initiator, a method of irradiating with UV light, a method of applying heat, a method of irradiating with light in the presence of a photopolymerization initiator, and the like.
In the polymerization step, it is preferable to use a polymerization initiator.
Examples of the polymerization initiator include hydrogen peroxide; persulfates such as sodium persulfate, potassium persulfate, and ammonium persulfate; dimethyl 2,2'-azobis(2-methylpropionate), 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2-methylpropionamidine) dihydrochloride (2,2'-azobis-2-amidinopropane dihydrochloride), 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine]hydrate, 2,2'-azobis[2-(2-imidazolin-2-yl)propane], 2,2'-azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride, 2,2'-azobis(1-imidazolin-2-yl)propane azo compounds such as 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), dimethyl 2,2'-azobis(2-methylpropionate), and 2,2'-azobis(2-methylbutyronitrile); organic peroxides such as benzoyl peroxide, lauroyl peroxide, peracetic acid, di-t-butyl peroxide, and cumene hydroperoxide; and redox initiators that generate radicals by combining an oxidizing agent and a reducing agent, such as ascorbic acid and hydrogen peroxide, and persulfates and metal salts. Among these polymerization initiators, hydrogen peroxide, persulfates, and azo compounds are preferred, and persulfates are more preferred, since there is a tendency for the amount of residual monomers to decrease. These polymerization initiators may be used alone or in the form of a mixture of two or more kinds.

The amount of the polymerization initiator used is preferably 0.1 g or more and 10 g or less, more preferably 0.2 g or more and 8 g or less, even more preferably 0.25 g or more and 7 g or less, and most preferably 0.3 g or more and 5 g or less, per 100 g of monomer used (total amount of amino group-containing monomer (A), hydrophobic monomer (B), hydrophilic group-containing monomer (C) and other monomer (E)).

In the above polymerization step, a chain transfer agent may be used as a molecular weight regulator for the polymer, if necessary. Specific examples of chain transfer agents include mercaptocarboxylic acids such as thioglycolic acid (mercaptoacetic acid), 3-mercaptopropionic acid, 2-mercaptopropionic acid (thiolactic acid), 4-mercaptobutanoic acid, thiomalic acid, and salts thereof, mercaptoethanol, thioglycerol, 2-mercaptoethanesulfonic acid, and the like; halides such as carbon tetrachloride, methylene chloride, bromoform, and bromotrichloroethane; secondary alcohols such as isopropanol and glycerin; phosphorous acid, hypophosphorous acid, hypophosphites, and hydrates thereof; hydrogen sulfite (salt) and compounds capable of generating hydrogen sulfite (salt) (bisulfite (salt), pyrosulfite (salt), dithionous acid (salt), sulfurous acid (salt), and the like); and the like. Among these, compounds having a mercapto group such as mercaptocarboxylic acid are preferred, and more preferred are mercapto group-containing compounds having a carboxyl group (mercaptocarboxylic acid).

The amount of chain transfer agent used in the production of the copolymer of the present invention is preferably 0.5 mol% or more and 30 mol% or less, more preferably 0.7 mol% or more and 25 mol% or less, even more preferably 0.8 mol% or more and 20 mol% or less, and most preferably 1 mol% or more and 10 mol% or less, based on 100 mol% of the amount of monomer (total monomers) used.

In the above polymerization step, the polymerization temperature is preferably 40°C or higher, and preferably 150°C or lower. More preferably, it is 50°C or higher, and even more preferably, it is 55°C or higher. Also, it is more preferably 120°C or lower, and even more preferably, it is 110°C or lower.

In the above polymerization step, the method of feeding the monomer components into the reaction vessel is not particularly limited, and examples thereof include a method of feeding the entire amount into the reaction vessel all at once at the beginning, a method of feeding the entire amount into the reaction vessel in portions or continuously, a method of feeding a part of the monomer components into the reaction vessel at the beginning and feeding the remainder into the reaction vessel in portions or continuously, etc. When a radical polymerization initiator is used, it may be charged into the reaction vessel from the beginning, or may be added dropwise to the reaction vessel, or these may be combined depending on the purpose.
The copolymer obtained as described above can be used as it is as a detergent additive such as an additive for liquid detergents, but if necessary, it may be further neutralized with an alkaline substance before use. As the alkaline substance, inorganic salts such as hydroxides and carbonates of monovalent or divalent metals, ammonia, and organic amines are suitable. Furthermore, after the reaction is completed, the concentration can be adjusted if necessary.

The solvent used during polymerization is appropriately selected from those that can dissolve the monomers and initiators used and the polymer to be produced, and includes water; alcohols with 1 to 8 carbon atoms such as ethanol, 1-propanol, 2-propanol, 1-butanol, and phenoxyethanol; glycols such as propylene glycol, butylene glycol, and hexylene glycol; polyalkylene glycols such as diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, and tetrapropylene glycol; diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, and diethylene glycol. Examples of suitable organic solvents include alkyl ethers such as cholesteryl monobutyl ether; sulfoxides such as sulfone, diethyl sulfone, and bis(2-hydroxyethyl) sulfone (e.g., dimethyl sulfoxide); cyclic ethers (e.g., tetrahydrofuran and tetrahydropyran); nitriles (e.g., acetonitrile, propionitrile, butyronitrile, acrylonitrile, and methacrylonitrile); carbonates (e.g., ethylene carbonate and propione carbonate); and ketones (e.g., acetone, diethyl ketone, acetophenone, methyl ethyl ketone, cyclohexanone, cyclopentanone, and diacetone alcohol). One or more of these may be used. Among these, water, ethanol, ethylene glycol, propylene glycol, diethylene glycol monobutyl ether, diethylene glycol monoethyl ether, and phenoxyethanol are preferred.

In the case where a precursor of the amino group-containing monomer (A) is used in the above polymerization step, an amino group can be introduced by reacting an amine compound with the polymerized reactant after the polymerization step.
An embodiment in which the above-mentioned production method includes a step of polymerizing a monomer component containing a precursor of the amino group-containing monomer (A) and a step of reacting the polymerization reactant obtained in the polymerization step with an amine compound is one of the preferred embodiments of the present invention.
The amine compound is not particularly limited as long as it can introduce an amino group into the polymerization reaction product, and examples thereof include alkyleneimines and compounds having an amino group and a functional group reactive with the precursor of the amino group-containing monomer (A). Among these, alkyleneimines are preferred, and ethyleneimines are more preferred.

The amount of the amine compound used in the step of reacting the amine compound is not particularly limited, but is preferably 50 to 1000 mol % relative to 100 mol % of the amount of the precursor of the amino group-containing monomer (A) used in the polymerization step. It is more preferably 50 to 500 mol %, and even more preferably 50 to 300 mol %.

In the second amino group-containing copolymer of the present invention, when the monomer (A2) has a structure in which some or all of the hydrogen atoms of the amino groups are substituted with a group having an alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms, the copolymer can be produced by reacting the polymerization reactant with an amine compound, and then substituting some or all of the hydrogen atoms of the amino groups of the resulting product with a compound having an alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms.

The compound having an alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms may be any compound having a functional group reactive with an amino group and the alkyl group or aryl group. Specific examples of the alkyl group or aryl group are as described above.
Examples of the functional group reactive with an amino group include a carboxyl group, a salt thereof, or a halide thereof, an epoxy group, and a halogeno group.
Specific examples of the compound having an alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms include lauric acid, butyl glycidyl ether, benzyl chloride, etc., with butyl glycidyl ether being preferred.

<Applications of amino group-containing copolymer>
The amino group-containing copolymer of the present invention is used for detergent applications and scale inhibitor applications.
Detergents include household detergents for clothing and dishes, detergents for the textile and other industrial industries, and hard surface cleaners, as well as detergents used for specific purposes only, such as bleaching detergents, which enhance the function of one of their ingredients.
That is, the present invention also relates to a detergent additive containing the above amino group-containing copolymer.
The present invention also relates to a method for using the amino group-containing copolymer as a detergent additive.
The present invention also relates to a detergent composition comprising the amino group-containing copolymer of the present invention and a detergent additive other than the copolymer.
The amino group-containing copolymer of the present invention has excellent compatibility with surfactants and can therefore be suitably used in liquid detergent applications. The detergent composition is preferably a liquid detergent composition.
The present invention further relates to a method for producing a detergent composition, the method including a step of adding the amino group-containing copolymer to a detergent additive other than the copolymer.
The detergent additives other than the amino group-containing copolymer of the present invention are not particularly limited as long as they are additives used in surfactants or ordinary detergents, and conventionally known knowledge in the detergent field can be appropriately referred to. Any appropriate additive can be used within a range that does not impair the effects of the present invention.
Another suitable application of the present invention is as a scale inhibitor, which is an agent used in water systems with scale buildup, such as cooling water systems, boiler water systems, water systems involved in membrane treatment, and water systems involved in reinjection wells in geothermal power plants.

Additives other than surfactants include, for example, anti-redeposition agents such as sodium carboxymethylcellulose to prevent redeposition of contaminants, stain inhibitors such as benzotriazole and ethylene-thiourea, soil release agents, color transfer inhibitors, fabric softeners, alkaline substances for adjusting pH, fragrances, solubilizers, fluorescent agents, colorants, foaming agents, foam stabilizers, polishing agents, bactericides, bleaching agents, bleaching aids, enzymes, dyes, solvents, etc. One or more of these can be used. In the case of powder detergent compositions, it is preferable to add zeolite.

The surfactant is preferably one or more selected from the group consisting of anionic surfactants, nonionic surfactants, cationic surfactants and amphoteric surfactants.

Preferred examples of the anionic surfactant include alkylbenzenesulfonates, alkyl ether sulfates, alkenyl ether sulfates, alkyl sulfates, alkenyl sulfates, α-olefinsulfonates, α-sulfofatty acids or ester salts, alkanesulfonates, saturated fatty acid salts, unsaturated fatty acid salts, alkyl ether carboxylates, alkenyl ether carboxylates, amino acid surfactants, N-acylamino acid surfactants, alkyl phosphates or salts thereof, and alkenyl phosphates or salts thereof. The alkyl and alkenyl groups in these anionic surfactants may be branched with an alkyl group such as a methyl group.

Preferable examples of the nonionic surfactant include polyoxyalkylene alkyl ethers, polyoxyalkylene alkenyl ethers, polyoxyethylene alkylphenyl ethers, higher fatty acid alkanolamides or their alkylene oxide adducts, sucrose fatty acid esters, alkyl glycoxides, fatty acid glycerin monoesters, and alkylamine oxides. The alkyl and alkenyl groups in these nonionic surfactants may be branched with alkyl groups such as methyl groups.

As the cationic surfactant, a quaternary ammonium salt or the like is preferable. As the amphoteric surfactant, a carboxyl-type amphoteric surfactant, a sulfobetaine-type amphoteric surfactant, or the like is preferable. The alkyl group and the alkenyl group in these cationic surfactants and amphoteric surfactants may be branched alkyl groups such as methyl groups.

The blending ratio of the surfactant is usually 10 to 80% by mass, preferably 15 to 75% by mass, more preferably 18 to 70% by mass, and particularly preferably 20 to 68% by mass, based on the total amount of the detergent composition. If the blending ratio of the surfactant is too low, there is a risk that the detergent composition will not be able to exhibit sufficient cleaning power, and if the blending ratio of the surfactant is too high, there is a risk that the cost-effectiveness will decrease.

Among the above surfactants, anionic surfactants and nonionic surfactants are preferred, and nonionic surfactants are particularly preferred. Nonionic surfactants are resistant to oily stains, so a liquid detergent composition containing the amino group-containing copolymer of the present invention and a nonionic surfactant will have superior cleaning power against oily stains. A liquid detergent composition containing the amino group-containing copolymer of the present invention and a nonionic surfactant is one of the preferred embodiments of the present invention.

The content of the nonionic surfactant is preferably 1 to 60% by mass, more preferably 3 to 60% by mass, and even more preferably 5 to 50% by mass, based on 100% by mass of the detergent composition.
The content of the nonionic surfactant is preferably 10 to 100% by mass, more preferably 15 to 90% by mass, and even more preferably 20 to 90% by mass, based on 100% by mass of the total amount of the surfactants.

The detergent composition preferably contains a hydrophilic solvent.
The hydrophilic solvent is not particularly limited, and any solvent normally used in liquid detergents can be used, including, for example, water; alcohols having 1 to 8 carbon atoms, such as ethanol, 1-propanol, 2-propanol, 1-butanol, and phenoxyethanol; glycols, such as propylene glycol, butylene glycol, and hexylene glycol; polyalkylene glycols, such as diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, and tetrapropylene glycol; diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, and diethylene glycol. Examples of the alkyl ether include alkyl ethers such as ethyl ether and butyl ether; sulfoxides such as sulfone, diethyl sulfone, and bis(2-hydroxyethyl) sulfone (dimethyl sulfoxide, etc.); cyclic ethers (tetrahydrofuran, tetrahydropyran, etc.); nitriles (acetonitrile, propionitrile, butyronitrile, acrylonitrile, methacrylonitrile, etc.); carbonates (ethylene carbonate, propione carbonate, etc.); ketones (acetone, diethyl ketone, acetophenone, methyl ethyl ketone, cyclohexanone, cyclopentanone, diacetone alcohol, etc.), and one or more of these can be used. Among these, ethanol, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, diethylene glycol monobutyl ether, diethylene glycol monoethyl ether, and phenoxyethanol are preferred.

The detergent composition preferably contains a hydrophilic solvent in a proportion of 0.1 to 30% by mass relative to 100% by mass of the liquid detergent composition. More preferably, it contains a hydrophilic solvent in a proportion of 1 to 27% by mass, and even more preferably, it contains a hydrophilic solvent in a proportion of 2 to 25% by mass.

The detergent composition may contain other detergent builders. Examples of other detergent builders include alkali builders such as carbonates, hydrogen carbonates, and silicates; chelate builders such as tripolyphosphates, pyrophosphates, Glauber's salt, nitrilotriacetates, ethylenediaminetetraacetates, citrates, (meth)acrylic acid copolymer salts, acrylic acid-maleic acid copolymers, fumarates, and zeolites; and carboxyl derivatives of polysaccharides such as carboxymethylcellulose. Countersalts used in the above other detergent builders include alkali metals such as sodium and potassium, and alkaline agents such as sodium hydroxide, ammonium, and amines.

When the detergent composition is a liquid detergent composition, the amount of water contained in the liquid detergent composition is usually, based on the total amount of the liquid detergent composition, preferably 0.1% by mass to 80% by mass, more preferably 2% by mass to 70% by mass, even more preferably 3% by mass to 60% by mass, even more preferably 5% by mass to 55% by mass, particularly preferably 5% by mass to 50% by mass, and most preferably 10% by mass to 50% by mass.

The detergent composition may contain an enzyme, such as, for example, a protease, a lipase, a cellulase, an amylase, etc.
The blending ratio of the above enzyme is usually preferably 5 mass % or less based on the total amount of the detergent composition.

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 mass" and "%" means "% by mass."

<Measurement of weight average molecular weight of copolymer>
The weight average molecular weight (Mw) of the copolymer was measured by GPC (gel permeation chromatography).
The measurement conditions and the apparatus are as follows:
Apparatus: Tosoh EcoSEC HLC-8320GPC
Detector: Differential refractometer (RI) Detector column: TSKgel α-M, α-2500 manufactured by Tosoh Corporation
Column temperature: 40°C
Flow rate: 0.4 mL / min
Injection volume: 20 μL (eluent preparation solution with sample concentration of 0.4 wt %)
Calibration curve: Polyethylene glycol manufactured by GL Sciences GPC software: EcoSEC-WS manufactured by Tosoh Corporation
Eluent: 0.5 M acetic acid + 0.2 M Na nitrate / acetonitrile = 50/50 (v/v)

Example 1
A glass separable flask equipped with a thermometer, a reflux condenser, and a stirrer was charged with 90 g of ethanol, and the temperature was raised to 70° C. under stirring. Next, under stirring, into the polymerization reaction system at a constant temperature of 70° C., 69.7 g of methoxypolyethylene glycol monomethacrylate (average number of moles of ethylene oxide added: 23, trade name "M-230G" manufactured by Shin-Nakamura Chemical Co., Ltd.), 14.1 g of methacrylic acid (hereinafter also referred to as MAA), and 22.4 g of ion-exchanged water were dropped from separate dropping nozzles. A monomer solution 1 consisting of 36 g of benzyl methacrylate (hereinafter also referred to as BnMA), and an aqueous initiator solution consisting of 13 g of a 5% ethanol solution of 2,2'-azobis(2,4-dimethylvaleronitrile) (trade name "V-65" manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) were each added dropwise. Concerning the dropping time, the dropping of the monomer solution and the aqueous initiator solution was started at the same time, and the monomer solution 1 was dropped for 120 minutes, the monomer solution 2 for 150 minutes, and the aqueous initiator solution for 180 minutes.
After the entire dropwise addition was completed, the reaction solution was kept at 70° C. for an additional 150 minutes to mature, thereby completing the polymerization, and thereby obtaining Precursor 1.
Ion-exchanged water was added to the solution containing Precursor 1, and the mixture was concentrated with a rotary evaporator to obtain an aqueous solution of Precursor 1. The solid content of Precursor 1 in the aqueous solution was 17.5%.
Into a separable glass flask equipped with a thermometer, a reflux condenser, and a stirrer, 111.4 g of the above-mentioned Precursor 1 aqueous solution, 38.6 g of ion-exchanged water, and 2.9 g of a 20% ethyleneimine (hereinafter also referred to as EI) aqueous solution were charged, and the temperature was raised to 70° C. with stirring and maintained for 120 minutes, thereby obtaining Copolymer 1.

Example 2
Into a separable glass flask equipped with a thermometer, a reflux condenser, and a stirrer, 111.4 g of the above-mentioned Precursor 1 aqueous solution, 38.6 g of ion-exchanged water, and 5.8 g of a 20% ethyleneimine (hereinafter also referred to as EI) aqueous solution were charged, and the temperature was raised to 70° C. with stirring and maintained for 120 minutes, thereby obtaining Copolymer 2.

Example 3
Into a separable glass flask equipped with a thermometer, a reflux condenser, and a stirrer, 111.4 g of the above-mentioned Precursor 1 aqueous solution, 38.6 g of ion-exchanged water, and 11.5 g of a 20% ethyleneimine (hereinafter also referred to as EI) aqueous solution were charged, and the temperature was raised to 70° C. with stirring and maintained for 120 minutes, thereby obtaining Copolymer 3.

Example 4
Into a separable glass flask equipped with a thermometer, a reflux condenser, and a stirrer, 111.4 g of the above-mentioned Precursor 1 aqueous solution, 38.6 g of ion-exchanged water, and 17.3 g of a 20% ethyleneimine (hereinafter also referred to as EI) aqueous solution were charged, and the temperature was raised to 70° C. with stirring and maintained for 120 minutes, thereby obtaining Copolymer 4.

Example 5
A separable glass flask equipped with a thermometer, a reflux condenser, and a stirrer was charged with 90 g of ethanol, and the temperature was raised to 70 ° C. under stirring. Next, under stirring, into the polymerization reaction system at a constant temperature of 70 ° C., methoxypolyethylene glycol monomethacrylate (average addition mole number of ethylene oxide 23, trade name "M-230G" manufactured by Shin-Nakamura Chemical Co., Ltd., hereinafter also referred to as PGM23E) 78 g, methacrylic acid (hereinafter also referred to as MAA.) 6 g, and ethanol 28 g of monomer solution 1; benzyl methacrylate (hereinafter also referred to as BnMA. Solubility parameter: 9.8) 36 g of monomer solution 2; 2,2'-azobis (2,4-dimethylvaleronitrile) (trade name "V-65" manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) 5% ethanol solution 17.1 g of an initiator aqueous solution were dropped from separate dropping nozzles. Concerning the dropping time, the dropping of the monomer solution and the aqueous initiator solution was started at the same time, and the monomer solution 1 was dropped for 120 minutes, the monomer solution 2 for 150 minutes, and the aqueous initiator solution for 180 minutes.
After the entire dropwise addition was completed, the reaction solution was kept at 70° C. for an additional 150 minutes to mature, thereby completing the polymerization, and thereby obtaining Precursor 2.
Ion-exchanged water was added to the solution containing precursor 2, and the solution was concentrated with a rotary evaporator to obtain a solution of precursor 2. The solid content of precursor 1 in the aqueous solution was 19.0%.
Into a separable glass flask equipped with a thermometer, a reflux condenser, and a stirrer, 157.4 g of the above-mentioned aqueous solution of Precursor 2, 72.6 g of ion-exchanged water, and 2.6 g of a 30% aqueous solution of ethyleneimine (hereinafter also referred to as EI) were charged, and the temperature was raised to 70° C. under stirring and maintained for 120 minutes, thereby obtaining Copolymer 5.

<Soil release evaluation>
The soil releasability of the copolymers 1 to 5 produced in Examples 1 to 5 and the above-mentioned precursors 1 and 2 as comparative copolymers 1 and 2 was evaluated by the following method.
<Fabric pretreatment method>
(1): Immersion conditions: Testfabiric's Style 730 (polyester fiber) was cut into 5 x 5 cm pieces. 300 g of an aqueous solution containing the copolymer obtained in the Examples and Comparative Examples adjusted to 50 ppm was prepared, and 5 g of the above-mentioned fabric was added while stirring with a magnetic stirrer, and stirred for 10 minutes. After 10 minutes, the fabric was dehydrated to three times its weight, and air-dried for one day.
(2): Washing conditions: Testfabiric's Style 730 (polyester fiber) was cut into 5 x 5 cm pieces. 300 g of an aqueous solution containing 250 ppm of Emulgen 108 (Kao Corporation) and 25 ppm of the copolymer obtained in the examples and comparative examples was prepared, and 5 g of the above fabric was added while stirring with a magnetic stirrer and stirred for 10 minutes. After 10 minutes, the fabric was rinsed, dehydrated, and air-dried for 1 day.

<Creating soiled cloth>
An oil-stained solution was prepared by mixing 61.5 g of olive oil, 37 g of oleic acid, 1 g of iron (III) oxide, and 0.5 g of oil red. 50 μL of this stained solution was dropped onto the polymer-treated cloth obtained by the above pretreatment method 1, and after leaving it for 1 hour, the excess oil was wiped off by sandwiching it between filter paper to prepare a stained cloth.

<Cleaning power evaluation>
(1)-1: Preparation of hardness mother liquor 8.39 g of calcium chloride dihydrate and 2.9 g of magnesium chloride hexahydrate were weighed into a beaker, and ion-exchanged water was added to bring the total weight to 1000 g.
(1)-2: Preparation of hard water 1.54 g of sodium hydrogen carbonate, 10 g of 0.1N hydrogen chloride, and 200 g of hardness mother liquor (1)-1 were placed in a beaker and diluted with ion-exchanged water to a total weight of 20,000 g.
(1)-3: Preparation of surfactant aqueous solution 13.85 g of Neopelex G-65 (Kao Corporation) and 3 g of Emulgen 108 (Kao Corporation) were weighed into a beaker, and ion-exchanged water was added to make up to 200 g to prepare a surfactant solution.
(2): Detergency test 16.67 g of the surfactant aqueous solution of (1)-3 and hard water of (1)-2 were mixed to prepare 4000 g of cleaning solution. The tergot meter was set to 25°C, and 500 g of cleaning solution was placed in a pot. Five stained cloths whose reflectance had been measured in advance with a color difference meter (SE-6000 manufactured by Nippon Denshoku Industries Co., Ltd.) and a cloth with a liquor ratio adjustment were placed in a pot totaling 16.67 g, and washed by stirring at 120 rpm for 10 minutes. The water in the pot was discarded, and the cloths were rinsed once, then dehydrated and air-dried for one day.
After air drying, the reflectance of the white cloth was measured again using a color difference meter, and the cleaning rate was calculated using the following formula. Based on the obtained cleaning rate, the cleaning power was evaluated according to the following criteria. The results are shown in Table 1.
: Cleaning rate of 90% or more, ◯: Cleaning rate of 60% or more but less than 90%, ×: Cleaning rate of less than 60%. In Table 1, MAA-EI100 indicates that 100 mol% of EI is added to 100 mol% of MAA. MAA-EI200 indicates that 200 mol% of EI is added to 100 mol% of MAA. MAA-EI300 indicates that 300 mol% of EI is added to 100 mol% of MAA.

Claims (7)

An amino group-containing copolymer,
The amino group-containing copolymer has the following formula (1-1):

(In the formula, R ¹ , R ² and R ³ are the same or different and represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. R ⁴ and R ⁵ are the same or different and represent a hydrogen atom, a (poly)alkyleneamino group which may have a substituent, or an alkyl group having 1 to 30 carbon atoms. However, when R ⁴ and R ⁵ are not both hydrogen atoms, at least one of R ⁴ and R ⁵ is a (poly)alkyleneamino group which may have a substituent and has a primary amino group. A ¹ is the same or different and represents an alkylene group having 2 to 18 carbon atoms, x1 is a number from 0 to 4, and y1 is 0 or 1. The copolymer has a structural unit (a1) represented by the formula (I), a structural unit (b) derived from a hydrophobic monomer (B), and a structural unit (c) derived from a hydrophilic group-containing monomer (C) having at least one hydrophilic group selected from the group consisting of a hydroxyl group, an oxyalkylene group, and a carboxyl group, a sulfonic acid group, a phosphoric acid group, a secondary or tertiary amino group, and salts thereof , and may have a structural unit (e) other than the structural units (a1), (b), and (c),
the contents of the structural units (a1), (b), (c) and (e) are 1 to 50 mass%, 5 to 50 mass%, 15 to 85 mass% and 0 to 10 mass%, respectively, relative to 100 mass% of all structural units;
The hydrophobic monomer (B) has a solubility parameter of a homopolymer of 13 or less and is represented by the following formula (4):

(wherein R ⁹ , R ¹⁰ and R ¹¹ are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms; and R ¹² represents a hydrocarbon group having 1 to 30 carbon atoms),
The hydrophilic group-containing monomer (C) contains a (poly)alkylene glycol monomer (C1), and the amino group-containing copolymer has a structural unit (c1) derived from the (poly)alkylene glycol monomer (C1), and the proportion of the structural unit (c1) is 15 to 85 mass% relative to 100 mass% of all structural units . An amino group-containing copolymer,
The amino group-containing copolymer has the following formula (1-2):

(In the formula, R ¹ , R ² and R ³ are the same or different and represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. R ^4' and R ^5' are the same or different and represent a hydrogen atom, a (poly)alkyleneamino group which may have a substituent, or an alkyl group having 1 to 30 carbon atoms, with the proviso that at least one of R ^4' and R ^5' is a (poly)alkyleneamino group which may have a substituent. A and ¹ are the same or different and represent an alkylene group having 2 to 18 carbon atoms. x1 represents a number from 0 to 4. y1 represents 0 or 1. The copolymer has a structural unit (a2) represented by the formula (I), a structural unit (b) derived from a hydrophobic monomer (B) , and a structural unit (c) derived from a hydrophilic group-containing monomer (C) having at least one hydrophilic group selected from the group consisting of a hydroxyl group, an oxyalkylene group, and a carboxyl group, a sulfonic acid group, a phosphoric acid group, a secondary or tertiary amino group, and salt groups thereof , and may have a structural unit (e) other than the structural units (a2), (b), and (c),
the contents of the structural units (a2), (b), (c) and (e) are 1 to 50 mass%, 5 to 50 mass%, 15 to 85 mass% and 0 to 10 mass%, respectively, relative to 100 mass% of all structural units;
The hydrophobic monomer (B) has a solubility parameter of a homopolymer of 13 or less and is represented by the following formula (4):

(wherein R ⁹ , R ¹⁰ and R ¹¹ are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms; and R ¹² represents a hydrocarbon group having 1 to 30 carbon atoms),
The hydrophilic group-containing monomer (C) contains a (poly)alkylene glycol monomer (C1), and the amino group-containing copolymer has a structural unit (c1) derived from the (poly)alkylene glycol monomer (C1), and the proportion of the structural unit (c1) is 15 to 85 mass% relative to 100 mass% of all structural units . The structural unit (a2) has a structure in which a part or all of the hydrogen atoms of the amino group contained in the structural unit ( a2 ) are substituted with a group having an alkyl group having 1 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms. The amino group-containing copolymer according to claim 1 , wherein the structural unit (a 1 ) has a (poly)alkyleneimine structure. 4. The amino group-containing copolymer according to claim 2, wherein the structural unit (a2) has a (poly)alkyleneimine structure. A detergent additive comprising the amino group-containing copolymer according to any one of claims 1 to 5 . 6. A detergent composition comprising the amino group-containing copolymer according to claim 1 and a detergent additive other than said copolymer.