JP2010138243A - Sulfonic acid group-containing copolymer, its manufacturing method, and its application - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polymer composition having further improved re-contamination prevention ability than conventional when it is used for use of a detergent, and its manufacturing method. <P>SOLUTION: The copolymer is a sulfonic acid group-containing copolymer obtained by polymerizing a monomer component containing a sulfonic acid group-containing monomer and a carboxyl group-containing monomer having one carboxyl group in the molecule in the presence of hydrogen peroxide. A composition of the structure (S) derived from the sulfonic acid group-containing monomer in the copolymer is <5 and ≤60 mass% (in terms of an acid type), a composition of the structure (C) derived from the carboxyl group-containing monomer is ≥40 and <95 mass% (in terms of an acid type), and the total of the compositions of the structure (S) and the structure (C) is 85-100 mass% (in terms of an acid type). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a sulfonic acid group-containing copolymer and a method for producing the same.

Conventionally, it is known that acrylic acid-based polymers having many carboxyl groups, maleic acid / acrylic acid-based copolymers, etc. have a calcium ion scavenging action, a clay dispersing action, etc. It is used in a wide range of applications such as inorganic pigment dispersants, flocculants, scale inhibitors, chelating agents, fiber treating agents and the like.

Various methods for producing the acrylic acid polymer have been disclosed, for example, Patent Document 1, Patent Document 2, and the like.
Patent Document 3 discloses that a copolymer obtained by essentially polymerizing a maleic acid monomer, an acrylic acid monomer, and a sulfonic acid group-containing monomer has good calcium ion scavenging ability, It is disclosed to exhibit clay dispersibility and gelation resistance in hardness water. Patent Document 3 discloses that the polymer is produced using a polymerization initiator made of hydrogen peroxide or the like.

Patent Document 4 discloses a copolymer of acrylic acid and sodium 3-allyloxy-2-hydroxy-1-propanesulfonate, which uses a sulfite as a chain transfer agent, and has good resistance to resistance. It is disclosed that it exhibits gel properties.
Here, with the recent increase in consumers' awareness of environmental issues, the performance required of detergent builders is changing. In other words, consumers like to save water by using the remaining hot water from the bath for washing, or prefer detergents with a small amount of use (compact detergent composition) by reducing the amount of detergent components to be drained. It has become.
The use of the remaining hot water causes a problem that the laundry must be washed under conditions where there are many dirt components and hardness components. In order to cope with the above problems, there is a demand for an agent having a higher anti-recontamination ability than before, which suppresses reattachment of soil components to fibers during washing.

JP-A-62-270605 JP-A-5-239114 JP 2000-355615 A JP 2002-3536 A

Thus, although various polymers have been reported in the past, there is a need for the development of a detergent builder that is further adapted to the current consumer needs described above.
Therefore, an object of the present invention is to provide a polymer having a detergency and a recontamination preventing ability which are further improved as compared with the conventional polymer when used in a detergent application, and a method for producing the same.

The present inventors have intensively studied to solve the above problems. As a result, the present inventors are a copolymer having a structure derived from a sulfonic acid group-containing monomer and a structure derived from a carboxyl group-containing monomer at a predetermined ratio, in the presence of hydrogen peroxide. It has been found that the copolymer polymerized in (1) has a high detergency and remarkably improved ability to prevent recontamination, thereby completing the present invention.
The copolymer according to the present invention is a sulfonic acid group-containing copolymer obtained by polymerizing a monomer component containing a sulfonic acid group-containing monomer and a carboxyl group-containing monomer in the presence of hydrogen peroxide. In addition, the composition of the structure (S) derived from the sulfonic acid group-containing monomer with respect to 100 mass% of the mass derived from all monomers of the copolymer is more than 5 and less than 60 mass% (acid type conversion) ) And
The composition of the structure derived from the carboxyl group-containing monomer (C) with respect to 100% by mass of the structure derived from all monomers of the copolymer is 40% by mass or more and less than 95% by mass (acid type conversion),
Sum of the composition of the structure (S) derived from the sulfonic acid group-containing monomer and the composition of the structure (C) derived from the carboxyl group-containing monomer with respect to 100% by mass of the structure derived from all monomers of the copolymer. Is 85% by mass or more and 100% by mass or less (in terms of acid type),
The carboxyl group-containing monomer is a monomer having one carboxyl group in the molecule.
A sulfonic acid group-containing copolymer.

  According to another aspect of the present invention, there is provided a method for producing the above sulfonic acid group-containing copolymer, wherein a monomer component containing a sulfonic acid group-containing monomer and a carboxyl group-containing monomer is mixed with hydrogen peroxide. There is provided a method for producing a sulfonic acid group-containing copolymer, characterized by polymerizing in the presence.

According to another aspect of the present invention, a sulfonic acid group-containing copolymer obtained by polymerizing a monomer component containing a sulfonic acid group-containing monomer and a carboxyl group-containing monomer in the presence of hydrogen peroxide. Because
The composition of the structure (S1) derived from the sulfonic acid group-containing monomer represented by the following general formula (s-1) with respect to 100% by mass of the structure derived from all monomers of the copolymer exceeds 5. 60 mass% or less (acid type conversion),
The composition of the structure derived from the carboxyl group-containing monomer (C) with respect to 100% by mass of the structure derived from all monomers of the copolymer is 40% by mass or more and less than 95% by mass (acid type conversion),
The composition of the structure (S1) derived from the sulfonic acid group-containing monomer represented by the following general formula (s-1) with respect to 100% by mass of the structure derived from all monomers of the copolymer and the carboxyl group-containing monomer The total composition of the structure derived from the monomer (C) is 85% by mass or more and 100% by mass or less (in terms of acid type),
The carboxyl group-containing monomer is a monomer having one carboxyl group in the molecule.
A sulfonic acid group-containing copolymer is provided.

In General Formula (s-1), R ₁ represents a single bond, CH ₂ , or CH ₂ CH ₂ structure, R ₂ represents a hydrogen atom or a methyl group, and X and Y represent a hydroxyl group or It represents SO ₃ M group, in SO ₃ M group, M represents hydrogen atom, Li, Na, and K, however, X, is either Y, represents a SO ₃ M group.

When the copolymer of the present invention (also referred to as the polymer of the present invention) is used as a detergent builder, the detergency is improved because the copolymer of the present invention has an excellent anti-recontamination ability. Therefore, it can be preferably used as a detergent additive. Further, due to the fact that the copolymer of the present invention has a sulfonic acid group, the detergency is synergistically improved by the interaction with the surfactant via the polyvalent ions.

Hereinafter, the present invention will be described in detail.
The copolymer of the present invention is derived from a structure derived from a specific sulfonic acid group-containing monomer (also referred to as a monomer having the structure of the general formula (s-1)) and a carboxyl group-containing monomer. It is a copolymer having a structure.
[Sulfonic acid group-containing unsaturated monomer]
The sulfonic acid group-containing monomer in the present invention is not particularly limited as long as it has a carbon-carbon double bond and a sulfonic acid group and / or a salt of a sulfonic acid group, and specifically, sulfoethyl (meth). Acrylate, 2-acrylamido-2-methylpropanesulfonic acid, styrenesulfonic acid, (meth) allylsulfonic acid, isoprenesulfonic acid, 3-allyloxy-2-hydroxy-1-propanesulfonic acid, vinylsulfonic acid, and salts thereof Etc. Here, examples of the salt include alkali metal salts, alkaline earth metal salts, ammonium salts, and quaternary amine salts, but alkali metal salts such as sodium salts and potassium salts are preferable.
However, since the resulting polymer has good stability, the sulfonic acid group-containing monomer includes styrene sulfonic acid, (meth) allyl sulfonic acid, isoprene sulfonic acid, 3-allyloxy-2-hydroxy-1 -Propanesulfonic acid, vinylsulfonic acid, and salts thereof are preferred.
In addition, since the resulting polymer has excellent detergent properties such as the ability to prevent recontamination, the sulfonic acid group-containing monomer includes 3-allyloxy-2-hydroxy-1-propanesulfonic acid, 3-allyloxy-2-hydroxy -1-Propanesulfonate is preferred.
A preferable sulfonic acid group-containing monomer in the present invention includes a sulfonic acid group-containing monomer having a structure represented by the following general formula (s-1).

In General Formula (s-1), R ₁ represents a single bond, CH ₂ , or CH ₂ CH ₂ structure, R ₂ represents a hydrogen atom or a methyl group, and X and Y represent a hydroxyl group or It represents SO ₃ M group, in SO ₃ M group, M represents hydrogen atom, Li, Na, and K, however, X, is either Y, represents a SO ₃ M group.
Here, in the present specification, the case where R ₁ is a single bond means that, for example, when it is represented as C—R ₁ —O, it becomes C—O.

When the copolymer has a structure derived from the monomer, the ability to prevent recontamination is improved. R ₁ is more preferably CH ₂ because the ability to prevent re-contamination of the copolymer tends to be further improved.

The composition of the structure derived from the sulfonic acid group-containing monomer with respect to 100% by mass of the structure derived from the total monomer of the copolymer is 5 to 60% by mass (acid type conversion), more preferably 10 to 55. It is mass% (acid type conversion), More preferably, it is 15-50 mass% (acid type conversion).
In the present invention, “acid type conversion” means the mass of the monomer with respect to all monomer components in the sulfonic acid group-containing monomer, carboxyl group-containing monomer, and other acid group-containing monomers. When calculating a ratio (composition ratio), it means calculating as a corresponding acid type monomer. The same applies when calculating the mass ratio of the copolymer derived from the monomer to the structure derived from all monomers. For example, when calculating the mass ratio of sodium acrylate to all monomer components, this means calculating the mass as the corresponding acid acrylic acid, and the structure derived from sodium acrylate is derived from all monomers. When calculating a mass ratio, it means mass calculating as a structure derived from acrylic acid which is a corresponding acid type structure. Similarly, structural units having an amine base-containing monomer and an amine salt structure similarly have a corresponding amine (amino group) -containing monomer and amine structure (amino group structure) when calculating the mass ratio. The mass is calculated as

  The copolymer of the present invention is characterized by having a structure (S) derived from a sulfonic acid group-containing monomer as an essential component. The structure (S) derived from the sulfonic acid group-containing monomer preferably has a structure (S1) derived from the sulfonic acid group-containing monomer represented by the general formula (s-1). In the present invention, the structure (S) derived from the sulfonic acid group-containing monomer is a structure in which the sulfonic acid group-containing monomer is copolymerized by radical polymerization. For example, when the sulfonic acid group-containing monomer is a sulfonic acid group-containing monomer represented by the general formula (s-1), the structure (S) derived from the sulfonic acid group-containing monomer is represented by the following general formula: It is represented by the formula (S1).

In General Formula (S1), R ₁ represents a single bond, CH ₂ , or CH ₂ CH ₂ structure, R ₂ represents a hydrogen atom or a methyl group, and X and Y represent a hydroxyl group or SO _3. M represents a group, and in the SO ₃ M group, M represents a hydrogen atom, Li, Na, K, provided that either X or Y represents a SO ₃ M group.
[Carboxyl group-containing monomer]
The carboxyl group-containing monomer of the present invention (carboxyl group-containing monomer in the present invention) is a monomer having one carboxyl group or a carboxyl group salt in the molecule.
The carboxyl group-containing monomer of the present invention is a monomer having a carboxyl group (or a salt of a carboxyl group) and a carbon-carbon double bond. Preferably, the carboxyl group-containing monomer of the present invention is a monomer having a carboxyl group (or a salt of a carboxyl group) and one carbon-carbon double bond (also referred to as monoethylenically unsaturated monocarboxylic acid). ). Examples of such a carboxyl group-containing monomer include (meth) acrylic acid, crotonic acid, and salts thereof. Among these, from the viewpoint that the copolymer having high polymerizability has a high ability to prevent recontamination, the carboxyl group-containing monomer is more preferably (meth) acrylic acid or (meth) acrylate. . These carboxyl group-containing monomers may be used alone or in combination of two or more.
In terms of structure, the carboxyl group-containing monomer corresponding to the sulfonic acid group-containing monomer of the present invention is calculated as a sulfonic acid group-containing monomer when calculating the mass ratio.

  The composition of the structure derived from a carboxyl group-containing monomer (C) with respect to 100% by mass of the structure derived from all monomers of the copolymer of the present invention is 40 to 95% by mass (acid type conversion), and more. Preferably it is 45-90 mass% (acid type conversion), More preferably, it is 50-85 mass% (acid type conversion).

The copolymer of the present invention is characterized by having a structure derived from a carboxyl group-containing monomer as an essential component. In the present invention, the structure derived from the carboxyl group-containing monomer (C) is a structure in which the carboxyl group-containing monomer is copolymerized by radical polymerization. For example, when the carboxyl group-containing monomer is acrylic acid, A structure represented by —CH ₂ —CH (COOH) —.
[Other monomers]
In addition to the sulfonic acid group-containing unsaturated monomer and the carboxyl group-containing monomer, other monomers copolymerizable with any of the monomers may be included. Other monomers are not particularly limited, but examples include acid group-containing monomers (excluding monomers corresponding to sulfonic acid group-containing unsaturated monomers and carboxyl group-containing monomers of the present invention). Examples of the acid group-containing monomer include maleic acid, fumaric acid, itaconic acid, dicarboxylic acid monomers such as 2-methyleneglutaric acid, vinylphosphonic acid, and (meth) allylphosphonic acid. Examples thereof include monomers having a phosphonic acid group. In addition, monomers obtained by adding 1 to 300 moles of alkylene oxide to unsaturated alcohols such as allyl alcohol, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, and polyalkylenes such as alkoxyalkylene glycol esters of (meth) acrylic acid Glycol chain-containing monomer: 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) Hydroxyl group-containing alkyl (meth) acrylates such as acrylate and α-hydroxymethylethyl (meth) acrylate; methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, (meth) acrylic Alkyl (meth) acrylates obtained by esterification of (meth) acrylic acid such as cyclohexyl acid, lauryl (meth) acrylate and alcohols having 1 to 18 carbon atoms; dimethylaminoethyl (meth) acrylate or a quaternized product thereof Amino group-containing acrylates such as; Amide group-containing monomers such as (meth) acrylamide, dimethylacrylamide and isopropylacrylamide; Vinyl esters such as vinyl acetate; Alkenes such as ethylene and propylene; Aromatic vinyls such as styrene Monomers; maleimide derivatives such as maleimide, phenylmaleimide, cyclohexylmaleimide; nitrile group-containing vinyl monomers such as (meth) acrylonitrile ;; aldehyde group-containing vinyl monomers such as (meth) acrolein; Methyl vinyl ether, Alkyl vinyl ethers such as ethyl vinyl ether and butyl vinyl ether; vinyl chloride, vinylidene chloride, allyl alcohol: other functional group-containing monomers such as vinyl pyrrolidone; and the like. Also about these other monomers, only 1 type may be used independently and 2 or more types may be used together.

  The composition of the structure (E) derived from another monomer with respect to 100% by mass of the structure derived from all monomers of the copolymer of the present invention is preferably 0 to 15% by mass. More preferably, it is 0-10 mass%, More preferably, it is 0-5 mass%. The structure (E) is an optional component, and may have the structure (E) or not at all depending on the application.

In the present invention, the structure derived from another monomer is a structure in which another monomer is copolymerized by radical polymerization. For example, when the other monomer is methyl acrylate, —CH ₂ —CH (COOCH ₃₎ - refers to a structure represented by.
In addition, sulfonic acid group-containing occupying the whole of the sulfonic acid group-containing monomer, carboxyl group-containing monomer and other monomers (also referred to as “total amount of monomer components” or “total monomer composition”) Although the ratio of the monomer is not particularly limited, the ratio of the sulfonic acid group-containing unsaturated monomer with respect to the total amount of the monomer component is preferably more than 5 from the viewpoint of sufficiently exerting the effects of the present invention. 60% by mass or less, more preferably more than 10 and 55% by mass or less, still more preferably more than 15 and 50% by mass or less.
The ratio of the carboxyl group-containing monomer in the total amount of the monomer component is not particularly limited, but from the viewpoint of sufficiently exerting the effects of the present invention, the carboxyl group-containing monomer with respect to the total amount of the monomer component. The ratio is preferably 40% by mass or more and less than 95% by mass, more preferably 45% by mass or more and less than 90% by mass, and still more preferably 50% by mass or more and less than 85% by mass.
The total of the proportion of the sulfonic acid group-containing unsaturated monomer and the proportion of the carboxyl group-containing monomer in the total amount of the monomer components is not particularly limited, but from the viewpoint of sufficiently exerting the effects of the present invention. Preferably, it is 85 mass% or more and 100 mass% or less, More preferably, it is 90 mass% or more and 100 mass% or less, More preferably, it is 95 mass% or more and 100 mass% or less.
The proportion of other monomers in the total amount of the monomer components is not particularly limited, but is preferably 0 to 15% by mass and more preferably 0 to 10% from the viewpoint of sufficiently exerting the effects of the present invention. It is mass%, More preferably, it is 0-5 mass%.

[Sulfonic acid group-containing copolymer]
As described above, the sulfonic acid group-containing copolymer of the present invention essentially includes a structure derived from the above-described sulfonic acid group-containing copolymer and a structure derived from a carboxyl group-containing monomer.
The sulfonic acid group-containing copolymer of the present invention is preferably obtained by copolymerizing a monomer component containing a sulfonic acid group-containing monomer and a carboxyl group-containing monomer.

  The weight average molecular weight of the sulfonic acid group-containing copolymer of the present invention is not particularly limited because it can be appropriately set in consideration of the desired performance as a detergent builder, etc., but the sulfonic acid group-containing copolymer of the present invention Specifically, the weight average molecular weight is preferably 500 to 200000, more preferably 1000 to 100,000, still more preferably 1500 to 50000, particularly preferably 2000 to 30000, and still more preferably. It is 3000-20000, Most preferably, it is 3500-15000. When the value of the weight average molecular weight is too large, the viscosity becomes high and handling may be complicated. On the other hand, if the value of the weight average molecular weight is too small, the ability to prevent recontamination is lowered, and there is a possibility that sufficient performance as a detergent builder may not be exhibited. In addition, the value measured by the method as described in the Example mentioned later shall be employ | adopted as a value of the weight average molecular weight of the sulfonic acid group containing copolymer of this invention.

  The number average molecular weight of the sulfonic acid group-containing copolymer of the present invention is not particularly limited because it can be appropriately set in consideration of desired performance as a detergent builder and the like. However, the sulfonic acid group-containing copolymer of the present invention is not particularly limited. Specifically, the number average molecular weight of the polymer is preferably 300 to 100,000, more preferably 500 to 50,000, still more preferably 800 to 25,000, particularly preferably 1000 to 15000, and even more preferably. Is 1500 to 10000, and most preferably 1800 to 8000. When the value of the number average molecular weight is too large, the viscosity becomes high and handling may be complicated. On the other hand, if the value of the number average molecular weight is too small, the ability to prevent recontamination is lowered, and there is a possibility that sufficient performance as a detergent builder may not be exhibited. In addition, the value measured by the method as described in the Example mentioned later shall be employ | adopted as a value of the number average molecular weight of the sulfonic acid group containing copolymer of this invention.

  The sulfonic acid group-containing copolymer of the present invention is preferably obtained by the method described in the section of [Method for producing sulfonic acid group-containing copolymer] described later.

  Composition of structure (S) derived from sulfonic acid group-containing monomer and composition of structure (C) derived from carboxyl group-containing monomer with respect to 100% by mass of the structure derived from all monomers of the copolymer of the present invention These are as described above, but the composition of the structure (S) derived from the sulfonic acid group-containing monomer and the carboxyl group-containing single monomer with respect to 100% by mass of the structure derived from all monomers of the copolymer of the present invention. The total composition of the structure derived from the monomer (C) is 85% by mass to 100% by mass, more preferably 90% by mass to 100% by mass, and still more preferably 85% by mass to 100% by mass. It is. By being the said range, the recontamination prevention ability of the copolymer of this invention improves.

[Method for producing sulfonic acid group-containing copolymer]
The method for producing a sulfonic acid group-containing copolymer of the present invention is characterized in that a monomer component containing a sulfonic acid group-containing monomer and a carboxyl group-containing monomer is copolymerized in the presence of hydrogen peroxide. However, unless otherwise specified, a known polymerization method or a modified method of a known method can be used.

  In the production method of the present invention, hydrogen peroxide acts as a polymerization initiator and / or a chain transfer agent. Therefore, the copolymer of the present invention usually has a hydroxyl group at one or both of the polymerization terminals.

  In the production method of the present invention, hydrogen peroxide is essential as an initiator system, and preferably one or more persulfates are used in combination. In some cases, a chain transfer agent or a polyvalent metal ion may be used (wherein the polyvalent metal ion serves as an initiator decomposition accelerator), and both of these may be used simultaneously. This will be specifically described below.

<Radical polymerization initiator>
Specific examples of the persulfate include sodium persulfate, potassium persulfate, and ammonium persulfate. Sodium persulfate is preferred.
Other known polymerization initiators can be used instead of or in addition to the persulfate, for example, dimethyl 2,2′-azobis (2-methylpropionate), 2,2 '-Azobis (2-amidinopropane) hydrochloride, 4,4'-azobis-4-cyanoparerenic acid, azobisisobutyronitrile, 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile) Suitable are azo compounds such as benzoyl peroxide, lauroyl peroxide, peracetic acid, di-t-butyl peroxide, cumene hydroperoxide and the like. Other known polymerization initiators can also be used alone or in combination of two or more.
The amount of hydrogen peroxide added is preferably 1.0 to 10.0 g, more preferably 2.0 to 8.0 g, with respect to 1 mol of the monomer. When the added amount of hydrogen peroxide is less than 2.0 g, the polymerization average molecular weight of the resulting sulfonic acid group-containing copolymer tends to increase. On the other hand, when the added amount exceeds 10.0 g, the effect of hydrogen peroxide cannot be obtained as the added amount increases, and the remaining hydrogen peroxide amount increases.

  The amount of the persulfate added is preferably 1.0 to 5.0 g and more preferably 2.0 to 4.0 g with respect to 1 mol of the monomer. If the amount of persulfate added is too small, the molecular weight of the resulting sulfonic acid group-containing copolymer tends to increase. On the other hand, if the addition amount is too large, the effect of persulfate cannot be obtained as the addition amount increases, and further, the purity of the resulting sulfonic acid group-containing copolymer is adversely affected.

  The addition ratio of hydrogen peroxide and persulfate is preferably 0.1 to 5.0 persulfate when the weight of hydrogen peroxide is 1 by weight. More preferably, it is -2.0. When the weight ratio of persulfate is less than 0.1, the weight average molecular weight of the resulting sulfonic acid group-containing copolymer tends to increase. On the other hand, if the weight ratio of persulfate exceeds 5.0, the persulfate is wasted in the polymerization reaction system in a state where the effect of lowering the molecular weight due to the addition of persulfate cannot be obtained as much as the addition. It will be.

  Further, as a method for adding hydrogen peroxide, it is preferable that the amount dripped substantially continuously with respect to the total amount used is 85% by weight or more, particularly preferably 90% by weight or more of the required predetermined amount. Most preferably, the entire amount is dropped. Hydrogen peroxide is dripped continuously, but the dripping speed may be changed.

  When the sulfonic acid group-containing monomer is a sulfonic acid group-containing monomer represented by the general formula (s-1), it is represented by hydrogen peroxide and the general formula (s-1). The ratio used for the polymerization of the sulfonic acid group-containing monomer is 5 to 50 g, preferably 10 to 40 g, of hydrogen peroxide per 1 mol of the sulfonic acid group-containing monomer. If the polymerization is carried out within this range, the clay dispersibility and the anti-recontamination ability of the resulting copolymer tend to be improved. Moreover, if it superposes | polymerizes in this range, it exists in the tendency which can suppress that the molecular weight of the copolymer obtained even if superposed | polymerized at high concentration becomes too large.

The dropping of hydrogen peroxide is delayed after the start of dropping of the carboxyl group-containing monomer (carboxyl group-containing monomer having one carboxyl group in the molecule) under the conditions of the polymerization temperature and pH at the time of polymerization described later. It is preferable to start. Preferably, hydrogen peroxide is dropped after 1 minute or more has passed since the start of dropping of the carboxyl group-containing monomer, more preferably after 3 minutes or more, more preferably after 5 minutes or more, and most preferably after 10 minutes or more. Is to start. By delaying the dropping start time of hydrogen peroxide, it is possible to smooth the initial polymerization start and narrow the molecular weight distribution.
The time for delaying the hydrogen peroxide dropping start time is preferably within 60 minutes, more preferably within 30 minutes after the start of dropping of the carboxyl group-containing monomer.
It is possible to start adding hydrogen peroxide at the same time as dropping the carboxyl group-containing monomer, and to charge hydrogen peroxide in advance before dropping the carboxyl group-containing monomer. Is preferably 10% or less of the required predetermined amount, more preferably 7% or less, still more preferably 5% or less, and particularly preferably 3% or less.
If hydrogen peroxide exceeding 10% of the required predetermined amount is added by the dropping start time of the carboxyl group-containing monomer, for example, when the persulfate is used in combination, the ratio of the concentration of hydrogen peroxide to the persulfate is large. The polymerization may be stopped. On the other hand, if it starts later than 60 minutes from the dropping start time of the carboxyl group-containing monomer, the chain transfer reaction due to hydrogen peroxide does not occur and the molecular weight at the initial stage of polymerization becomes high.

  The hydrogen peroxide dropping end time is preferably completed simultaneously with the monomer dropping end time under the conditions of the polymerization temperature and pH at the time of polymerization described later, and is 10 minutes or more earlier than the monomer dropping end time. It is more preferable to end, and it is particularly preferable to end 30 minutes or more early. In addition, even if it complete | finishes later than the dripping completion time of a monomer, it does not have a bad influence in a polymerization system especially. However, since the added hydrogen peroxide is not completely decomposed by the end of the polymerization, the effect as hydrogen peroxide is not obtained and is wasted, and a large amount of hydrogen peroxide may remain. This is not preferable because it may adversely affect the thermal stability of the obtained copolymer.

  In addition, the persulfate addition method is not particularly limited in view of its decomposability and the like, but the amount dripped substantially continuously with respect to the total use amount is 50% by weight or more of the required predetermined amount. It is particularly preferable that the content is 80% by weight or more, and it is most preferable to add the whole amount dropwise. The persulfate is dripped continuously, but the dripping speed may be changed.

  Although there is no particular limitation on the dropping time, under the conditions of the polymerization temperature and pH at the time of polymerization described below, in the initiator having relatively quick decomposition, such as persulfates such as ammonium persulfate, potassium persulfate, and sodium persulfate. It is preferable to drop until the monomer dropping end time, more preferably within 30 minutes after the monomer dropping ends, and particularly within 5 to 20 minutes after the monomer dropping. preferable. Thereby, the effect which can reduce the residual amount of the monomer in a copolymer remarkably can be found. It should be noted that, even if the addition of these initiators is completed before the completion of the monomer addition, it does not particularly adversely affect the polymerization, and is set according to the residual amount of monomer in the obtained copolymer. It is good.

  For these initiators that are relatively quick to decompose, the preferred range is described only for the dropping end time, but the dropping start time is not limited at all and may be set as appropriate. For example, in some cases, the dropping of the initiator may be started before the start of dropping of the monomer, or in the case of a combined system in particular, the dropping of one initiator is started and a certain time has elapsed. Then, or after completion, another initiator may be dropped. Any of these may be set as appropriate according to the decomposition rate of the initiator and the reactivity of the monomer.

  The concentration of the radical polymerization initiator at the time of addition is not particularly limited, but is preferably 5 to 60% by weight, particularly preferably 10 to 50% by weight. If the concentration of the initiator is less than 5% by weight, the monomer concentration during polymerization will be very low as a result, so that the monomer polymerizability can be very poor. The remaining amount of the body becomes very large. Further, the efficiency and productivity of transportation and the like are lowered, which is not preferable from the economical aspect. On the other hand, if it exceeds 60% by weight, there is a problem in terms of safety and ease of dripping.

<Chain transfer agent>
The method for producing the sulfonic acid group-containing copolymer of the present invention may be used in combination with hydrogen peroxide or the like as a molecular weight regulator of the polymer, as long as it does not adversely affect the polymerization. good. Specific examples of the chain transfer agent include mercaptoethanol, thioglycerol, thioglycolic acid, 2-mercaptopropion, 3-mercaptopropion, thiomalic acid, octyl thioglycolate, octyl 3-mercaptopropionate, 2- Thiol chain transfer agents such as mercaptoethanesulfonic acid, n-dodecyl mercaptan, octyl mercaptan, butylthioglycolate; halides such as carbon tetrachloride, methylene chloride, bromoform, bromotrichloroethane; Secondary alcohol; phosphorous acid, hypophosphorous acid, and salts thereof (sodium hypophosphite, potassium hypophosphite, etc.), sulfurous acid, hydrogen sulfite, dithionic acid, metabisulfite, and salts thereof ( Sodium bisulfite, potassium bisulfite , Sodium dithionite, potassium dithionite, sodium metabisulfite, metabisulfite potassium, etc.) and the like, and the like lower oxides and salts thereof. The chain transfer agent may be used alone or in the form of a mixture of two or more.

  Of the above chain transfer agents, sulfurous acid, bisulfite, dithionite, metabisulfite, and salts thereof (sodium bisulfite, potassium bisulfite, sodium dithionite, potassium dithionite, sodium metabisulfite) , Potassium metabisulfite, etc.), crystal precipitation may occur under cold conditions due to an increase in the amount of impurities in the sulfonic acid group-containing copolymer aqueous solution. Therefore, from these viewpoints, it is preferable to set their use to a minimum.

<Reaction accelerator>
In the method for producing a sulfonic acid group-containing copolymer of the present invention, a reaction accelerator may be added for the purpose of reducing the amount of an initiator used. Examples of the reaction accelerator include heavy metal ions. In the present invention, the heavy metal ion means a metal having a specific gravity of 4 g / cm ³ or more. As said metal ion, iron, cobalt, manganese, chromium, molybdenum, tungsten, copper, silver, gold, lead, platinum, iridium, osmium, palladium, rhodium, ruthenium etc. are preferable, for example. These heavy metals can be used alone or in combination of two or more. Among these, iron is more preferable. The ionic valence of the heavy metal ions is not particularly limited. For example, when iron is used as the heavy metal, the iron ions in the initiator may be Fe ²⁺ or Fe ³⁺ , and these may be combined. May be.
The heavy metal ions are not particularly limited as long as they are included in the form of ions. However, it is preferable to use a method using a solution in which a heavy metal compound is dissolved because the handleability is excellent. The heavy metal compound used in that case should just contain the heavy metal ion desired to contain in an initiator, and can be determined according to the initiator to be used. When iron is used as the heavy metal ion, the mole salt (Fe (NH ₄ ) ₂ (SO ₄ ) ₂ · 6H ₂ O), ferrous sulfate · 7 hydrate, ferrous chloride, ferric chloride, etc. It is preferable to use a heavy metal compound or the like. Moreover, when using manganese as a heavy metal ion, manganese chloride etc. can be used suitably. In the case of using these heavy metal compounds, since they are water-soluble compounds, they can be used in the form of an aqueous solution and have excellent handleability. The solvent of the solution obtained by dissolving the heavy metal compound is not limited to water, and does not hinder the polymerization reaction in the production of the hydrophobic group-containing copolymer of the present invention, and is a heavy metal compound. As long as it dissolves.

  The method for adding the heavy metal ions is not particularly limited, but it is preferably added before the completion of the dropwise addition of the monomer, and it is particularly preferable to initially charge the entire amount. Further, the amount used is preferably 100 ppm or less, more preferably 70 ppm or less, still more preferably 50 ppm or less, and particularly preferably 30 ppm or less with respect to the total amount of the reaction solution. If it exceeds 100 ppm, the added effect is no longer seen, and the resulting copolymer is highly colored, which may be unusable when used as a detergent composition.

  The content of the heavy metal ions is preferably 0.1 to 10 ppm with respect to the total mass of the polymerization reaction solution at the completion of the polymerization reaction. If the content of heavy metal ions is less than 0.1 ppm, the effect of heavy metal ions may not be sufficiently exhibited. On the other hand, when the content of heavy metal ions exceeds 10 ppm, the color tone of the resulting copolymer may be deteriorated. Moreover, when there is much content of heavy metal ion, when using the copolymer which is a product as a detergent builder, there exists a possibility of becoming a cause of coloring stain | pollution | contamination.

  The time when the polymerization reaction is completed means the time when the polymerization reaction is substantially completed in the polymerization reaction solution and a desired polymer is obtained. For example, when the polymer polymerized in the polymerization reaction solution is neutralized with an alkali component, the content of heavy metal ions is calculated based on the total mass of the polymerization reaction solution after neutralization. When two or more kinds of heavy metal ions are included, the total amount of heavy metal ions may be in the above range.

The combination of the chain transfer agent, the initiator and the reaction accelerator can be appropriately selected within the above range. Preferred examples include sodium bisulfite (SBS) / hydrogen peroxide (H ₂ O ₂ ), sodium bisulfite (SBS) / hydrogen peroxide (H ₂ O ₂ ) / Fe, sodium bisulfite (SBS) / persulfuric acid. Sodium (NaPS) / hydrogen peroxide (H ₂ O ₂ ), sodium persulfate (NaPS) / hydrogen peroxide (H ₂ O ₂ ), sodium persulfate (NaPS) / hydrogen peroxide (H ₂ O ₂ ) / Fe Etc.

  In the method for producing a sulfonic acid group-containing copolymer of the present invention, a polymerization catalyst decomposition catalyst or a reducing compound may be added to the reaction system in addition to the above-described compounds during polymerization. Examples of the decomposition catalyst for the polymerization initiator include metal halides such as lithium chloride and lithium bromide; metal oxides such as titanium oxide and silicon dioxide; hydrochloric acid, hydrobromic acid, perchloric acid, sulfuric acid, nitric acid and the like. Metal salts of inorganic acids; carboxylic acids such as formic acid, acetic acid, propionic acid, lactic acid, isolacic acid, benzoic acid, their esters and their metal salts; heterocyclic amines such as pyridine, indole, imidazole, carbazole and their derivatives Can be mentioned. These decomposition catalysts may be used alone or in combination of two or more.

  Examples of the reducing compound include organic metal compounds such as ferrocene; iron naphthenate, copper naphthenate, nickel naphthenate, cobalt naphthenate, manganese naphthenate, and the like, such as iron, copper, nickel, cobalt, and manganese. Inorganic compounds capable of generating metal ions; boron trifluoride ether adducts, potassium permanganate, perchloric acid and other inorganic compounds; sulfur dioxide, sulfite, sulfate, bisulfite, thiosulfate, sulfoxide, Sulfur-containing compounds such as benzenesulfinic acid and its substitutes, and homologues of cyclic sulfinic acid such as p-toluenesulfinic acid; octyl mercaptan, dodecyl mercaptan, mercaptoethanol, α-mercaptopropionic acid, thioglycolic acid, thiopropionic acid, α -Sodium thiopropionate sulfopropyl es Tercap, mercapto compounds such as α-thiopropionic acid sodium sulfoethyl ester; nitrogen-containing compounds such as hydrazine, β-hydroxyethyl hydrazine, hydroxylamine; formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde, isobutyraldehyde, isovaleraldehyde Aldehydes such as ascorbic acid and the like. These reducing compounds may also be used alone or in combination of two or more. A reducing compound such as a mercapto compound may be added as a chain transfer agent.

  The total amount of the chain transfer agent, initiator, and reaction accelerator used is the total monomer component 1 comprising a sulfonic acid group-containing monomer, a carboxyl group-containing monomer, and, if necessary, other monomers. It is preferable that it is 2-20g with respect to a mole. By setting it as such a range, the hydrophobic group containing copolymer of this invention can be produced efficiently, and the molecular weight distribution of a hydrophobic group containing copolymer can be made into a desired thing. More preferably, it is 4-18g, More preferably, it is 6-15g.

As a method for adding the polymerization initiator and the chain transfer agent to the reaction vessel, a continuous charging method such as dropping or divided charging can be applied. Further, the chain transfer agent may be introduced alone into the reaction vessel, or may be confused in advance with each monomer, solvent, etc. constituting the monomer component.

  In the above copolymerization method, monomer components, polymerization initiators, etc. can be added to the reaction vessel by charging all of the monomer components into the reaction vessel and adding the polymerization initiator into the reaction vessel. Method of performing polymerization: charging a part of the monomer component into the reaction vessel, and adding the polymerization initiator and the remaining monomer component continuously or stepwise (preferably continuously) into the reaction vessel. A method in which a polymerization solvent is charged in a reaction vessel and a total amount of monomer components and a polymerization initiator is added; a part of the monomer is charged in a reaction vessel, and a polymerization initiator is added. A method of carrying out copolymerization by adding the remaining monomer components into the reaction vessel (preferably continuously) is suitable. Among such methods, the molecular weight distribution of the obtained copolymer can be narrowed (sharpened), and the dispersibility when used as a detergent builder can be improved. It is preferable to carry out copolymerization by a method in which body components are successively dropped into a reaction vessel.

  The copolymerization method can be carried out by commonly used methods such as solution polymerization, bulk polymerization, suspension polymerization, and emulsion polymerization, and is not particularly limited, but solution polymerization is preferred. As described above, the solvent that can be used in this case is preferably a mixed solvent in which 50% by mass of water or water is based on the total solvent. When only water is used, it is preferable in that the solvent removal step can be omitted.

  The copolymerization method can be carried out either batchwise or continuously. In addition, a known solvent can be used as needed during copolymerization, and water; alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol; glycerin; polyethylene glycol; benzene, toluene, xylene Aromatic or aliphatic hydrocarbons such as cyclohexane and n-heptane; Esters such as ethyl acetate; Ketones such as acetone and methyl ethyl ketone; Amides such as dimethylformaldehyde; Ethers such as diethyl ether and dioxane It is. These may be used alone or in combination of two or more. Among these, from the viewpoint of the solubility of the monomer component and the resulting copolymer, one or more solvents selected from the group consisting of water and lower alcohols having 1 to 4 carbon atoms may be used. preferable.

<Degree of neutralization during polymerization>
The degree of neutralization during polymerization (ie during monomer dropping) is 99 mol% or less, preferably 50 to 95 mol%, based on the total amount of acid amounts of the carboxyl group-containing monomer and the sulfonic acid group-containing monomer. It is as follows. If the degree of neutralization is less than 50 mol%, hydrogen peroxide is not sufficiently decomposed and the weight average molecular weight tends to be high. Also, if it exceeds 99 mol%, strong alkaline and corrosive conditions are required, so that the production equipment may be corroded at high temperatures, and furthermore, hydrogen peroxide is decomposed by alkali, so that the addition amount may increase. There is also. The degree of neutralization after the completion of polymerization (that is, after completion of monomer dropping) is the sum of the acid amounts of the carboxyl group-containing monomer and the sulfonic acid group-containing monomer in order to promote the decomposition of the remaining hydrogen peroxide. Preferably it is 80 mol% or more with respect to quantity, More preferably, it is 90 mol% or more, More preferably, you may be 95 mol% or more.

  Examples of monomer neutralizers include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide; alkaline earth metal hydroxides such as calcium hydroxide and magnesium hydroxide: ammonia; monoethanolamine; And organic amines such as triethanolamine. These may be used alone or as a mixture of two or more. Preferred are alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, and particularly preferred is sodium hydroxide. Hereinafter, in the present invention, these are simply referred to as “neutralizing agents”.

  Neutralization may be performed in advance before supplying the monomer to the reactor, or the monomer and the neutralizing agent may be separately supplied to the reactor and neutralized in the reactor. good. Further, the degree of neutralization from the start of polymerization to the end of polymerization need not be constant as long as it is within the above range. Specifically, the degree of neutralization may be lowered in the first half of the polymerization, or The neutralization degree may be increased in the latter half of the polymerization.

  The concentration of the neutralizing agent at the time of addition is not particularly limited, but is preferably 10 to 70% by weight, particularly preferably 30 to 50% by weight. If the concentration of the neutralizing agent is less than 10% by weight, the monomer concentration during the polymerization will be very low as a result. The remaining amount of the body becomes very large. Moreover, the efficiency and productivity of transportation and the like are lowered, which is not preferable from the economical aspect. On the other hand, if it exceeds 70% by weight, it is not preferable in terms of safety and ease of dripping.

<Polymerization temperature>
The temperature at the time of polymerization is not particularly limited at the time of initial charging, and from the start of polymerization due to the start of dropping of the monomer or polymerization initiator to the end of polymerization (that is, all dropping of the monomer, polymerization initiator, etc. is completed). Up to 60.degree. C., more preferably 90.degree. C. or more, particularly near the boiling point of the polymerization solvent, and most preferably the boiling point of the polymerization solvent. When pH adjustment and concentration adjustment are performed after the completion of polymerization, it is not particularly limited and may be appropriately performed.
If the temperature at the time of polymerization is less than 60 ° C., the residual amount of the monomer in the resulting polymer tends to decrease and the recontamination preventing ability tends to decrease, such being undesirable. In addition, the polymerization at the boiling point is very preferable because the temperature control becomes very easy, and therefore the reproducibility of the polymerization is good, and the obtained polymer is very stable in quality. However, when there is large foaming, the boiling point or lower is preferable.
The temperature at the time of polymerization need not always be kept constant during the progress of the polymerization reaction. For example, the polymerization is started from room temperature, and the temperature is increased to a set temperature at an appropriate temperature increase time or temperature increase rate. Thereafter, the set temperature may be maintained, or the polymerization temperature may be varied (increased or decreased) over time during the course of the polymerization reaction, depending on the dropping method of the monomer component, initiator, and the like. Also good.

<Polymerization concentration>
It is preferable to set the solid content concentration at the end of dropping of all monomers to 30 or more and 50 or less. More preferably, it is 35 or more and 45 or less.
When polymerized at the above-mentioned concentration, the residual sulfonic acid group-containing monomer tends to be reduced. Moreover, the clay dispersibility and the recontamination prevention ability of the resulting copolymer tend to be improved.

<Polymerization time>
The polymerization time is not particularly limited, but is preferably 30 to 420 minutes, more preferably 45 to 390 minutes, still more preferably 60 to 360 minutes, and most preferably 90 to 300 minutes. In the present invention, “polymerization time” represents the time during which a monomer is added unless otherwise specified.
<Pressure during polymerization>
The pressure in the reaction system may be any of normal pressure (atmospheric pressure), reduced pressure, and increased pressure, but from the viewpoint of the molecular weight of the polymer obtained, the reaction system is sealed under normal pressure. However, it is preferably performed under pressure. Moreover, it is preferable to carry out under normal pressure (atmospheric pressure) in terms of equipment such as a pressurizing device, a decompressing device, a pressure-resistant reaction vessel, and piping. The atmosphere in the reaction system may be an air atmosphere, but is preferably an inert atmosphere. For example, the inside of the system is preferably replaced with an inert gas such as nitrogen before the start of polymerization.

[Sulfonic acid group-containing copolymer composition (polymer composition)]
The sulfonic acid group-containing copolymer of the present invention is essential in the polymer composition of the present invention. A solvent such as water may be included. In addition, unreacted sulfonic acid group-containing monomers, unreacted carboxyl group-containing monomers, unreacted polymerization raw materials such as unreacted polymerization initiators, and by-products such as polymerization initiator decomposition products are included. It can be done.
When the polymer composition of this invention contains hydrogen peroxide, since coloring of a polymer composition is suppressed, it is preferable. In terms of suppressing coloring, it is preferably 200 ppm or more, more preferably 500 ppm or more, and most preferably 1000 ppm or more with respect to the mass of the polymer composition immediately after production.
The content of the unreacted sulfonic acid group-containing unsaturated monomer present in the polymer composition of the present invention is preferably less than 3% by mass with respect to 100% by mass of the solid content of the polymer composition. More preferably, it is less than 2% by mass. The content of the unreacted carboxyl group-containing monomer present in the polymer composition is preferably 1000 ppm by mass or less, more preferably 100 masses with respect to 100 mass% of the solid content of the polymer composition. ppm or less, and most preferably 0 ppm by mass.
The polymer composition of the present invention is not particularly limited, but is preferably obtained without undergoing a purification step such as impurity removal from the viewpoint of production efficiency. Furthermore, after the polymerization step, the polymer composition of the present invention is obtained by diluting the obtained polymerization composition with a small amount of water for handling convenience (about 1 to 400% by mass with respect to the obtained mixture). Included in the composition.

Since the sulfonic acid group-containing copolymer composition of the present invention uses hydrogen peroxide as a chain transfer agent or the like, impurities are present in comparison with sulfonic acid group-containing copolymers using other chain transfer agents. It has the feature of few. Thereby, for example, compared to the polymer disclosed in Patent Document 4, precipitation of by-products under cold conditions is suppressed. Therefore, it can be preferably applied to various uses.
The polymer and polymer composition of the present invention can be used as a water treatment agent, fiber treatment agent, dispersant, detergent builder (or detergent composition) and the like. As a detergent builder, it can be used by adding to detergents for various uses such as clothing, tableware, residential, hair, body, toothpaste, and automobile.

<Water treatment agent>
The sulfonic acid group-containing copolymer or polymer composition of the present invention can be used as a water treatment agent. If necessary, the water treatment agent may contain a polymerized phosphate, phosphonate, anticorrosive, slime control agent, and chelating agent as other compounding agents.

  The water treatment agent is useful for scale prevention in a cooling water circulation system, a boiler water circulation system, a seawater desalination apparatus, a pulp digester, a black liquor concentration tank, and the like. Further, any appropriate water-soluble polymer may be included as long as it does not affect the performance and effects.

<Fiber treatment agent>
The sulfonic acid group-containing copolymer or polymer composition of the present invention can be used as a fiber treatment agent. The fiber treatment agent includes at least one selected from the group consisting of a dye, a peroxide and a surfactant, and the polymer composition of the present invention.

  The content of the sulfonic acid group-containing copolymer of the present invention in the fiber treatment agent is preferably 1 to 100% by weight, more preferably 5 to 100% by weight, based on the entire fiber treatment agent. Further, any appropriate water-soluble polymer may be included as long as the performance and effects are not affected.

  Below, the compounding example of the fiber processing agent which is closer to embodiment is shown. This fiber treatment agent can be used in the steps of refining, dyeing, bleaching and soaping in fiber treatment. Examples of dyeing agents, peroxides and surfactants include those usually used for fiber treatment agents.

  The blending ratio of the sulfonic acid group-containing copolymer of the present invention to at least one selected from the group consisting of a dye, a peroxide and a surfactant is, for example, the whiteness of the fiber, the color unevenness, the dyeing tempering degree. In order to improve the above, at least one selected from the group consisting of a dye, a peroxide and a surfactant is added to 1 part by weight of the polymer composition of the present invention in terms of pure amount of the fiber treatment agent. It is preferable to use a composition blended at a ratio of 0.1 to 100 parts by weight as a fiber treatment agent.

  Arbitrary appropriate fiber can be employ | adopted as a fiber which can use the said fiber processing agent. Examples thereof include cellulosic fibers such as cotton and hemp, chemical fibers such as nylon and polyester, animal fibers such as wool and silk, semi-synthetic fibers such as human silk, and woven fabrics and blended products thereof.

  When the fiber treatment agent is applied to the refining process, it is preferable to blend the polymer composition of the present invention with an alkali agent and a surfactant. In the case of applying to the bleaching step, it is preferable to blend the polymer composition of the present invention, a peroxide, and a silicic acid-based agent such as sodium silicate as a decomposition inhibitor for the alkaline bleaching agent.

<Inorganic pigment dispersant>
The sulfonic acid group-containing copolymer or polymer composition of the present invention can be used as an inorganic pigment dispersant. If necessary, the inorganic pigment dispersant may contain condensed phosphoric acid and its salt, phosphonic acid and its salt, and polyvinyl alcohol as other compounding agents.

  The content of the sulfonic acid group-containing copolymer of the present invention in the inorganic pigment dispersant is preferably 5 to 100% by weight with respect to the whole inorganic pigment dispersant. Further, any appropriate water-soluble polymer may be included as long as it does not affect the performance and effect.

  The inorganic pigment dispersant can exhibit good performance as a dispersant for heavy or light calcium carbonate or clay inorganic pigment used in paper coating. For example, by adding a small amount of an inorganic pigment dispersant to an inorganic pigment and dispersing it in water, high concentration calcium carbonate having low viscosity and high fluidity and good aging stability of their performance. High concentration inorganic pigment slurries such as slurries can be produced.

  When the inorganic pigment dispersant is used as a dispersant for an inorganic pigment, the amount of the inorganic pigment dispersant used is preferably 0.05 to 2.0 parts by weight with respect to 100 parts by weight of the inorganic pigment. When the amount of the inorganic pigment dispersant used is within the above range, a sufficient dispersion effect can be obtained, and an effect commensurate with the addition amount can be obtained, which can be economically advantageous.

<Detergent composition>
The sulfonic acid group-containing copolymer or polymer composition of the present invention can also be added to a detergent composition.
Although the polymer composition of the present invention includes the sulfonic acid group-containing copolymer described above, the content of the sulfonic acid group-containing copolymer in the detergent composition is not particularly limited. However, from the viewpoint of exhibiting excellent builder performance, the content of the sulfonic acid group-containing copolymer is preferably 0.1 to 15% by mass, more preferably based on the total amount of the detergent composition. Is 0.3-10 mass%, More preferably, it is 0.5-5 mass%.
Detergent compositions used in detergent applications usually include surfactants and additives used in detergents. Specific forms of these surfactants and additives are not particularly limited, and conventionally known knowledge can be appropriately referred to in the detergent field. The detergent composition may be a powder detergent composition or a liquid detergent composition.
The surfactant is one or more selected from the group consisting of an anionic surfactant, a nonionic surfactant, a cationic surfactant and an amphoteric surfactant. When two or more kinds are used in combination, the total amount of the anionic surfactant and the nonionic surfactant is preferably 50% by mass or more, more preferably 60% by mass with respect to the total amount of the surfactant. It is above, More preferably, it is 70 mass% or more, Most preferably, it is 80 mass% or more.
Examples of the anionic surfactant include alkylbenzene sulfonate, alkyl ether sulfate, alkenyl ether sulfate, alkyl sulfate, alkenyl sulfate, α-olefin sulfonate, α-sulfo fatty acid or ester salt, alkane sulfonate. , Saturated fatty acid salt, unsaturated fatty acid salt, alkyl ether carboxylate, alkenyl ether carboxylate, amino acid type surfactant, N-acyl amino acid type surfactant, alkyl phosphate ester or salt thereof, alkenyl phosphate ester or Its salts are preferred. An alkyl group such as a methyl group may be branched from the alkyl group or alkenyl group in these anionic surfactants.
Nonionic surfactants 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. Esters, alkylamine oxides and the like are preferred. An alkyl group such as a methyl group may be branched from the alkyl group or alkenyl group in these nonionic surfactants.
As the cationic surfactant, a quaternary ammonium salt or the like is suitable. As the amphoteric surfactant, a carboxyl type amphoteric surfactant, a sulfobetaine type amphoteric surfactant, and the like are suitable. The alkyl group and alkenyl group in these cationic surfactants and amphoteric surfactants may be branched from an alkyl group such as a methyl group.
The blending ratio of the surfactant is usually 10 to 60% by mass, preferably 15 to 50% by mass, more preferably 20 to 45% by mass, particularly preferably based on the total amount of the detergent composition. Is 25-40 mass%. If the surfactant content is too small, sufficient detergency may not be achieved, and if the surfactant content is too high, the economy may be reduced.
Additives include anti-redeposition agents to prevent redeposition of contaminants such as alkali builders, chelate builders, sodium carboxymethylcellulose, stain inhibitors such as benzotriazole and ethylene-thiourea, soil release agents, and color transfer. Inhibitors, softeners, alkaline substances for pH adjustment, fragrances, solubilizers, fluorescent agents, colorants, foaming agents, foam stabilizers, polishes, bactericides, bleaching agents, bleaching aids, enzymes, dyes A solvent or the like is preferable. In the case of a powder detergent composition, it is preferable to blend zeolite.
The detergent composition may include other detergent builders in addition to the polymer composition of the present invention. Other detergent builders are not particularly limited, but include, for example, alkali builders such as carbonates, hydrogen carbonates, silicates, tripolyphosphates, pyrophosphates, bow glass, nitrilotriacetate, ethylenediaminetetraacetate, citrate. Examples thereof include acid salts, (meth) acrylic acid copolymer salts, acrylic acid-maleic acid copolymers, chelate builders such as fumarate and zeolite, and carboxyl derivatives of polysaccharides such as carboxymethylcellulose. Examples of the counter salt used in the builder include alkali metals such as sodium and potassium, ammonium and amine.
The total blending ratio of the additive and other builder for detergent is usually preferably 0.1 to 50% by mass with respect to 100% by mass of the cleaning composition. More preferably, it is 0.2-40 mass%, More preferably, it is 0.3-35 mass%, Most preferably, it is 0.4-30 mass%, Most preferably, it is 0.5-20 mass% or less. It is. If the additive / other detergent builder content is less than 0.1% by mass, sufficient detergent performance may not be achieved, and if it exceeds 50% by mass, the economy may be reduced.
In addition, the concept of the above-mentioned detergent composition includes specific uses such as synthetic detergents for household detergents, textile industry and other industrial detergents, hard surface cleaners, and bleach detergents that enhance one of the components. Detergents that are only used are also included.
When the detergent composition is a liquid detergent composition, the amount of water contained in the liquid detergent composition is usually preferably 0.1 to 75% by mass, more preferably based on the total amount of the liquid detergent composition. Is 0.2 to 70% by mass, more preferably 0.5 to 65% by mass, even more preferably 0.7 to 60% by mass, particularly preferably 1 to 55% by mass, Preferably it is 1.5-50 mass%.
When the detergent composition is a liquid detergent composition, the detergent composition preferably has a kaolin turbidity of 200 mg / L or less, more preferably 150 mg / L or less, and even more preferably 120 mg / L or less. Especially preferably, it is 100 mg / L or less, Most preferably, it is 50 mg / L or less.
Further, the change (difference) in kaolin turbidity when the sulfonic acid group-containing copolymer or polymer composition of the present invention is added to the liquid detergent composition as a detergent builder is 500 mg / L or less. Preferably, it is 400 mg / L or less, more preferably 300 mg / L or less, particularly preferably 200 mg / L or less, and most preferably 100 mg / L or less. As the kaolin turbidity value, a value measured by the following method is adopted.

<Measurement method of kaolin turbidity>
A sample (liquid detergent) uniformly stirred in a 50 mm square cell having a thickness of 10 mm was removed and air bubbles were removed. Then, the NDU2000 (trade name, turbidimeter) manufactured by Nippon Denshoku Co., Ltd. was used at 25 ° C. Kaolin turbidity: mg / L) is measured.
Proteases, lipases, cellulases, and the like are suitable as enzymes that can be incorporated into the cleaning composition. Of these, proteases, alkaline lipases, and alkaline cellulases that are highly active in an alkaline cleaning solution are preferred.
The amount of the enzyme added is preferably 5% by mass or less with respect to 100% by mass of the cleaning composition. If it exceeds 5% by mass, improvement in detergency cannot be seen, and the economy may be reduced.
Even when the detergent composition is used in an area of hard water (for example, 100 mg / L or more) having a high concentration of calcium ions and magnesium ions, salt precipitation is small and has an excellent cleaning effect. This effect is particularly pronounced when the detergent composition contains an anionic surfactant such as LAS.

The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by mass” and “%” means “% by mass”.
Further, the weight average molecular weight of the sulfonic acid group-containing copolymer of the present invention, the ability to prevent recontamination, the amount of unreacted monomers, the solid content of the polymer composition and the aqueous polymer solution were measured according to the following methods. .

<Measurement conditions of weight average molecular weight (GPC)>
Apparatus: L-7000 series detector manufactured by Hitachi, Ltd. Detector: RI
Column: SHODEX Asahipak GF-310-HQ, GF-710-HQ, GF-1G 7B manufactured by Showa Denko KK
Column temperature: 40 ° C
Flow rate: 0.5 mL / min
Calibration curve: POLYACRYLIC ACID STANDARD made by Soka Science Co., Ltd.
Eluent: 0.1N sodium acetate / acetonitrile = 3/1 (mass ratio)
<Polymer composition, method for measuring solid content of copolymer aqueous solution>
In a nitrogen atmosphere, the polymer composition (polymer composition 1.0 g + water 3.0 g) was left to dry for 1 hour in an oven heated to 130 ° C. From the weight change before and after drying, the solid content (%) and the volatile component (%) were calculated.

<Measurement of content of carboxyl group-containing monomer, sulfonic acid group-containing monomer, etc. in polymer composition>
The monomer was measured using liquid chromatography under the conditions shown in Table 1 below.
Measuring device: L-7000 series detector manufactured by Hitachi, Ltd .: UV detector L-7400 manufactured by Hitachi, Ltd.
Column: SHODEX RSpak DE-413 manufactured by Showa Denko Co., Ltd.
Temperature: 40.0 ° C
Eluent: 0.1% phosphoric acid aqueous solution Flow rate: 1.0 ml / min
<Measurement method of recontamination prevention ability (precontamination prevention rate)>
(1) A polyester cloth obtained from Test fabric was cut into 5 cm × 5 cm to prepare a white cloth. The whiteness of the white cloth was measured by reflectance using a colorimetric color difference meter SE2000 type manufactured by Nippon Denshoku Industries Co., Ltd. in advance.
(2) Hard water was prepared by adding pure water to 4.41 g of calcium chloride dihydrate to 15 kg.
(3) Pure water was added to 4.0 g of sodium linear alkylbenzene sulfonate, 6.0 g of sodium carbonate, and 2.0 g of sodium sulfate to make 100.0 g to prepare an aqueous surfactant solution.
(4) A targot meter is set at 25 ° C., 1 L of hard water, 5 g of a surfactant aqueous solution, 1 g of a 2% polymer aqueous solution in terms of solid content, 0.15 g of zeolite, and 0.25 g of carbon black are put in a pot, and 100 rpm For 1 minute. Then, 10 white cloths were put and stirred at 100 rpm for 10 minutes.
(5) The white cloth was drained by hand, 1 L of tap water adjusted to 25 ° C. was placed in the pot, and stirred at 100 rpm for 2 minutes. This was done twice.
(6) A white cloth was applied and dried while stretching the wrinkle with an iron, and then the whiteness of the white cloth was measured again with the above colorimetric colorimeter with reflectance.
(7) The recontamination prevention rate was calculated from the above measurement results using the following formula.

<Example 1>
In a 1000 mL glass separable flask equipped with a reflux condenser and a stirrer (paddle blade), 68.0 g of pure water and a 40% aqueous solution of sodium 3-allyloxy-2-hydroxypropanesulfonate (hereinafter referred to as “40% It is also referred to as “HAPS”.) 244.1 g was charged, and the temperature was raised to the boiling point while stirring to obtain a polymerization reaction system. Next, 162.0 g of an 80% aqueous solution of acrylic acid (hereinafter also referred to as “80% AA”) and an aqueous solution of 48% sodium hydroxide (hereinafter referred to as “48%”) in the polymerization reaction system maintained at the boiling point under stirring. 103.1 g, 15% sodium persulfate aqueous solution (hereinafter also referred to as “15% NaPS”) 45.0 g, and 35% hydrogen peroxide (hereinafter referred to as “35% H ₂ O ₂ ”). Also referred to as 3) 32.1 g was dropped from separate nozzles. The dropping time of each solution is 180 minutes for 80% AA, 150 minutes for 48% NaOH after 30 minutes from the start of dropping 80% AA, 190 minutes for 15% NaPS, and 80 minutes for 35% H ₂ O _2. It was set to 135 minutes from 15 minutes after the start of dropping of% AA. Moreover, the dropping rate of each solution was made constant, and each solution was dropped continuously.
After completion of the dropwise addition of 80% AA, the reaction solution was kept at the boiling point (ripening) for 30 minutes to complete the polymerization. After completion of the polymerization, 9.4 g of 48% NaOH was gradually added dropwise while stirring and allowing the polymerization reaction liquid to cool, thereby neutralizing the polymerization reaction liquid.
Thus, an aqueous solution (sulfonic acid group-containing copolymer composition 1) of polymer 1 (sulfonic acid group-containing copolymer 1) having a solid content concentration of 44.8% and a weight average molecular weight of 17,000 was obtained.

<Example 2>
A 1000 mL glass separable flask equipped with a reflux condenser and a stirrer (paddle blade) was charged with 151.0 g of pure water and 244.1 g of 40% HAPS, and the temperature was raised to the boiling point while stirring. It was. Next, 162.0 g of 80% AA, 103.1 g of 48% NaOH, 45.0 g of 15% NaPS, and 32% of 35% H ₂ O ₂ were placed in the polymerization reaction system maintained at the boiling point under stirring. 0.1 g was dropped from separate nozzles. The dropping time of each solution is 180 minutes for 80% AA, 150 minutes for 48% NaOH after 30 minutes from the start of dropping 80% AA, 190 minutes for 15% NaPS, and 80 minutes for 35% H ₂ O _2. It was set to 135 minutes from 15 minutes after the start of dropping of% AA. Moreover, the dropping rate of each solution was made constant, and each solution was dropped continuously.
After completion of the dropwise addition of 80% AA, the reaction solution was kept at the boiling point (ripening) for 30 minutes to complete the polymerization. After completion of the polymerization, 9.4 g of 48% NaOH was gradually added dropwise while stirring and allowing the polymerization reaction liquid to cool, thereby neutralizing the polymerization reaction liquid.
Thus, an aqueous solution (sulfonic acid group-containing copolymer composition 2) of polymer 2 (sulfonic acid group-containing copolymer 2) having a solid content concentration of 40.2% and a weight average molecular weight of 12,000 was obtained.

<Example 3>
A 1000 mL glass separable flask equipped with a reflux condenser and a stirrer (paddle blade) was charged with 145.9 g of pure water and 191.5 g of 40% HAPS, and the temperature was raised to the boiling point while stirring to polymerize the reaction system. It was. Next, 180.0 g of 80% AA, 122.5 g of 48% NaOH, 47.1 g of 15% NaPS, and 33% of 35% H ₂ O ₂ were added to the polymerization reaction system maintained at the boiling point under stirring. .6 g, each dropped from a separate nozzle. The dropping time of each solution is 180 minutes for 80% AA, 160 minutes for 20% after the start of 80% AA dropping for 48% NaOH, 190 minutes for 15% NaPS, and 80 minutes for 35% H ₂ O _2. It was set to 135 minutes from 15 minutes after the start of dropping of% AA. Moreover, the dropping rate of each solution was made constant, and each solution was dropped continuously.
After completion of the dropwise addition of 80% AA, the reaction solution was kept at the boiling point (ripening) for 30 minutes to complete the polymerization. After completion of the polymerization, 9.8 g of 48% NaOH was gradually added dropwise while stirring and allowing the polymerization reaction liquid to cool, thereby neutralizing the polymerization reaction liquid.
Thus, an aqueous solution (sulfonic acid group-containing copolymer composition 3) of polymer 3 (sulfonic acid group-containing copolymer 3) having a solid content concentration of 41.0% and a weight average molecular weight of 13,000 was obtained.

<Example 4>
A glass separable flask with a capacity of 1000 mL equipped with a reflux condenser and a stirrer (paddle blade) was charged with 248.1 g of pure water and 244.1 g of 40% HAPS, and the temperature was raised to the boiling point while stirring to polymerize the reaction system. It was. Next, 162.0 g of 80% AA, 103.1 g of 48% NaOH, 45.0 g of 15% NaPS, and 19% of 35% H ₂ O ₂ were added to the polymerization reaction system maintained at the boiling point under stirring. .3 g, each dropped from a separate nozzle. The dropping time of each solution was 180 minutes for 80% AA, 150 minutes for 48% NaOH after 30 minutes from the start of dropping 80% AA, 190 minutes for 15% NaPS, and 150 minutes for 35% H ₂ O _2. Minutes. Moreover, the dropping rate of each solution was made constant, and each solution was dropped continuously.
After completion of the dropwise addition of 80% AA, the reaction solution was kept at the boiling point (ripening) for 30 minutes to complete the polymerization. Thus, an aqueous solution (sulfonic acid group-containing copolymer composition 4) of polymer 4 (sulfonic acid group-containing copolymer 4) having a solid content concentration of 36.4% and a weight average molecular weight of 11,000 was obtained.

<Example 5>
A 1000 mL glass separable flask equipped with a reflux condenser and a stirrer (paddle blade) was charged with 298.3 g of pure water and 191.5 g of 40% HAPS, and the temperature was raised to the boiling point while stirring. It was. Next, 180.0 g of 80% AA, 122.5 g of 48% NaOH, 47.1 g of 15% NaPS, and 20% of 35% H ₂ O ₂ were added to the polymerization reaction system maintained at the boiling point under stirring. .2 g, each dropped from separate nozzles. The dropping time of each solution is 180 minutes for 80% AA, 160 minutes for 20% after the start of 80% AA dropping for 48% NaOH, 190 minutes for 15% NaPS, and 150 minutes for 35% H ₂ O _2. Minutes. Moreover, the dropping rate of each solution was made constant, and each solution was dropped continuously.
After completion of the dropwise addition of 80% AA, the reaction solution was kept at the boiling point (ripening) for 30 minutes to complete the polymerization. After completion of the polymerization, 9.8 g of 48% NaOH was gradually added dropwise while stirring and allowing the polymerization reaction liquid to cool, thereby neutralizing the polymerization reaction liquid.
Thus, an aqueous solution (sulfonic acid group-containing copolymer composition 5) of polymer 5 (sulfonic acid group-containing copolymer 5) having a solid content concentration of 35.3% and a weight average molecular weight of 10,000 was obtained.

<Example 6>
In a 1000 mL glass separable flask equipped with a reflux condenser and a stirrer (paddle blade), 120.0 g of pure water, 9.4 g of maleic anhydride (hereinafter also referred to as “MA”), and 40% HAPS 191. 5 g was charged and the temperature was raised to the boiling point while stirring to obtain a polymerization reaction system. Next, 132.9 g of 80% AA, 118.1 g of 48% NaOH, 38.5 g of 15% NaPS, and 27% of 35% H ₂ O ₂ were added to the polymerization reaction system maintained at the boiling point under stirring. .5 g, each dropped from separate nozzles. The dropping time of each solution is 180 minutes for 80% AA, 160 minutes for 20% after the start of 80% AA dropping for 48% NaOH, 190 minutes for 15% NaPS, and 80 minutes for 35% H ₂ O _2. It was set to 135 minutes from 15 minutes after the start of dropping of% AA. Moreover, the dropping rate of each solution was made constant, and each solution was dropped continuously.
After completion of the dropwise addition of 80% AA, the reaction solution was kept at the boiling point (ripening) for 30 minutes to complete the polymerization. After completion of the polymerization, 6.9 g of 48% NaOH was gradually added dropwise while stirring and allowing the polymerization reaction liquid to cool, thereby neutralizing the polymerization reaction liquid.
Thus, an aqueous solution (sulfonic acid group-containing copolymer composition 6) of polymer 6 (sulfonic acid group-containing copolymer 6) having a solid content concentration of 41.3% and a weight average molecular weight of 11,000 was obtained.

<Comparative Example 1>
A 1000 mL glass separable flask equipped with a reflux condenser and a stirrer (paddle blade) was charged with 20.0 g of pure water and 0.014 g of Mole salt, and the temperature was raised to 90 ° C. while stirring to polymerize the reaction. It was a system. Next, 162.0 g of 80% AA, 244.1 g of 40% HAPS, 45.0 g of 15% NaPS, and 45.0 g of 35% SBS were placed in a polymerization reaction system maintained at 90 ° C. with stirring. Each was dropped from a separate nozzle. The dropping time of each solution was 180 minutes for 80% AA, 120 minutes for 40% HAPS, 190 minutes for 15% NaPS, and 175 minutes for 35% SBS. Moreover, the dropping rate of each solution was made constant, and each solution was dropped continuously.
After the completion of the dropwise addition of 80% AA, the reaction solution was kept at 90 ° C. (ripening) for 30 minutes to complete the polymerization. After completion of the polymerization, while stirring and allowing the polymerization reaction liquid to cool, 127.5 g of 48% NaOH was gradually added dropwise to neutralize the polymerization reaction liquid.
Thus, an aqueous solution of comparative polymer 1 having a solid content concentration of 45.5% and a weight average molecular weight of 11,000 was obtained.

<Comparative example 2>
A 1000 mL glass separable flask equipped with a reflux condenser and a stirrer (paddle blade) was charged with 31.0 g of pure water and 0.012 g of Mole salt, and the temperature was raised to 90 ° C. while stirring to polymerize the reaction. It was a system. Next, in a polymerization reaction system maintained at 90 ° C. with stirring, 162.0 g of 80% AA, 174.5 g of 40% HAPS, 42.4 g of 15% NaPS, and 30.3 g of 35% SBS. Each was dropped from a separate nozzle. The dropping time of each solution was 180 minutes for 80% AA, 150 minutes for 40% HAPS, 190 minutes for 15% NaPS, and 175 minutes for 35% SBS. Moreover, the dropping rate of each solution was made constant, and each solution was dropped continuously.
After the completion of the dropwise addition of 80% AA, the reaction solution was kept at 90 ° C. (ripening) for 30 minutes to complete the polymerization. After completion of the polymerization, while stirring and allowing the polymerization reaction liquid to cool, 127.5 g of 48% NaOH was gradually added dropwise to neutralize the polymerization reaction liquid.
Thus, an aqueous solution of comparative polymer 2 having a solid content concentration of 45.0% and a weight average molecular weight of 12,000 was obtained.

<Example 7>
The results of measuring the recontamination preventing ability of the sulfonic acid group-containing copolymers obtained in Examples 1 to 6 and Comparative Examples 1 and 2 are summarized in a table.

From the results shown in Table 1, it was demonstrated that the polymer of the present invention has an excellent ability to prevent recontamination as compared with conventional polymers.
Therefore, when the polymer of the present invention is used as a detergent builder, it is expected that recontamination of dirt can be effectively prevented even if washing is performed using the remaining bath water.

Claims (3)

A sulfonic acid group-containing copolymer obtained by polymerizing a monomer component containing a sulfonic acid group-containing monomer and a carboxyl group-containing monomer in the presence of hydrogen peroxide,
The composition of the structure (S) derived from the sulfonic acid group-containing monomer with respect to 100 mass% of the mass derived from all monomers of the copolymer is more than 5 and 60 mass% or less (acid type conversion). ,
The composition of the structure derived from the carboxyl group-containing monomer (C) with respect to 100% by mass of the structure derived from all monomers of the copolymer is 40% by mass or more and less than 95% by mass (acid type conversion),
Sum of the composition of the structure (S) derived from the sulfonic acid group-containing monomer and the composition of the structure (C) derived from the carboxyl group-containing monomer with respect to 100% by mass of the structure derived from all monomers of the copolymer. Is 85% by mass or more and 100% by mass or less (in terms of acid type),
The carboxyl group-containing monomer is a monomer having one carboxyl group in the molecule.
A sulfonic acid group-containing copolymer. A monomer component including a sulfonic acid group-containing monomer and a carboxyl group-containing monomer is polymerized in the presence of hydrogen peroxide,
2. A process for producing a sulfonic acid group-containing copolymer according to claim 1. A detergent composition comprising the sulfonic acid group-containing copolymer according to claim 1.