JP2934391B2 - Maleic acid / (meth) acrylic acid copolymer and use thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a maleic acid / (meth) acrylic acid copolymer having a specific range of molecular weight cutoff and copolymer composition. The present invention also relates to a detergent composition containing a maleic acid / (meth) acrylic acid copolymer having a specific range of molecular weight cutoff and copolymer composition, an inorganic pigment dispersant, and a fiber treating agent.

[0002]

2. Description of the Related Art It has been known that a maleic acid / (meth) acrylic acid-based copolymer having many carboxyl groups exhibits excellent chelating and dispersing effects. It is used in a wide range of applications, such as flocculants, scale inhibitors, chelating agents, fiber treatment agents, and detergents.

[0003] Although the polymerizability of maleic acid is generally low, it is necessary to obtain a maleic acid / (meth) acrylic acid copolymer having a large number of carboxyl groups in the molecule, which is suitably used for the above-mentioned applications. If the proportion of the maleic acid component charged during the polymerization is increased, the following problems occur.

(1) The polymerization time is further increased due to poor polymerizability.

(2) If the ratio of the charged maleic acid component is high, a large amount of hydrogen peroxide (polymerization initiator) must be used.

(3) When a large amount of hydrogen peroxide is used, a large amount of hydrogen peroxide remains after polymerization.

(4) A large amount of unreacted maleic acid remains even though a large amount of hydrogen peroxide (polymerization initiator) is used.

(5) The resulting maleic acid / (meth) acrylic acid-based copolymer has a large amount of maleic acid and hydrogen peroxide remaining thereon, so that the chelating action and the dispersing action are not sufficiently satisfactory. It is not suitable for the above uses.

For example, Japanese Patent Publication No. 3-2167 discloses an example in which a maleic acid / (meth) acrylic acid copolymer is used as a pigment dispersant, but there is no illustration of a detergent composition. Here, the maleic acid / (meth) acrylic acid-based copolymer is prepared by putting a maleic acid component in a reaction vessel, and simultaneously starting and terminating the dropping of acrylic acid and a hydrogen peroxide solution. , Maleic acid / (meth) acrylic acid at a pH of 3.5 to 5.0. However, according to this method, the obtained maleic acid / (meth) acrylic acid copolymer has a wide molecular weight distribution, a low maleic acid copolymerization ratio in the molecular weight cut off of the high molecular weight portion, and a decrease in the reaction solution at the end of the reaction. A large amount of residual maleic acid remains despite the use of a large amount of hydrogen peroxide during polymerization, and a large amount of hydrogen peroxide also remains.

Japanese Patent Application Laid-Open No. 62-218407 discloses an example in which a maleic acid / acrylic acid copolymer is used as a dispersant and a detergent composition. It cannot be said that the detergent composition disclosed in this publication has improved detergency as compared with a general detergent composition, and does not have a desired balance of properties desired as a detergent. Here, the maleic acid-based copolymer is prepared by putting a maleic acid component in a reaction vessel, and simultaneously starting and ending the dropping of acrylic acid and a hydrogen peroxide solution. The pH
It is obtained by polymerization while maintaining at about 4 to about 6. The maleic acid / acrylic acid-based copolymer obtained in the same manner as described above has a wide molecular weight distribution, a low maleic acid copolymerization ratio in the molecular weight cutoff of the high molecular weight portion, and residual maleic acid in the reaction solution at the end of the reaction. Even though a large amount of hydrogen peroxide is used during polymerization, a large amount of hydrogen peroxide remains, and a large amount of hydrogen peroxide also remains.

Furthermore, Japanese Patent Publication No. 3-14046 discloses that a copolymer of ethylenically unsaturated mono- and dicarboxylic acids is used as a skin-forming inhibitor in detergents and cleaners. There is no example. In the same manner as described above, the ethylenically unsaturated mono- and dicarboxylic acid copolymer is charged with the ethylenically unsaturated dicarboxylic acid component in a reaction vessel, and the ethylenically unsaturated monocarboxylic acid component and hydrogen peroxide are added dropwise. Are started at the same time and ended at the same time. However, in the polymer obtained by this reaction, a large number of carboxyl groups having a high maleic acid content could not be uniformly introduced into the polymer, and only a polymer having a wide molecular weight distribution could be obtained.

[0012] The maleic acid-based copolymer obtained by the conventional reaction did not exhibit sufficient performance even when used in various applications, particularly in detergent compositions. In particular, the maleic acid-based copolymer obtained by the conventional reaction has a wide molecular weight distribution, and it is difficult to optimally control the ratio of maleic acid / acrylic acid in each molecular weight component. When an acrylic acid-based copolymer is used as a detergent composition, the chelating action and the dispersing action are insufficient, and the detergent performance is reduced.

[0013]

SUMMARY OF THE INVENTION The inventors of the present invention have studied what kind of molecular weight distribution and copolymer composition of a maleic acid / (meth) acrylic acid copolymer is important, When the maleic acid / (meth) acrylic acid copolymer has a specific ratio of molecular weight cut-off and a specific copolymerization ratio for each molecular weight cut-off, the calcium ion trapping ability and the clay dispersing ability are greatly enhanced. It has been found that when used as a detergent composition, the detergency can be greatly improved, and the performance as an inorganic pigment dispersant and a fiber treatment agent can be drastically enhanced. Thus, the present invention has been completed.
Accordingly, an object of the present invention is to obtain a maleic acid / (meth) acrylic acid-based copolymer having a specific molecular weight distribution and a specific copolymer composition, and which is very useful for various uses.

[0014]

The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that the molecular weight distribution of the maleic acid / (meth) acrylic acid-based copolymer, the ratio of the fractional molecular weights, The copolymerization ratio of the molecular weight cutoff, and maleic acid /
The present invention has been completed by focusing on the calcium ion trapping ability, calcium ion stability constant, clay dispersing ability, clay adsorbing ability, and gelling property of the (meth) acrylic acid-based copolymer.

That is, according to the present invention, the molecular weight cut off using a gel permeation chromatogram is as follows:
An object of the present invention is to provide a maleic acid / (meth) acrylic acid copolymer which satisfies the conditions of (7) to (7).

(1) Less than 20% of a component having a molecular weight of 30,000 or more and a maleic acid / (meth) acrylic acid molar ratio of 5
0/50 to 10/90 (2) 1 to 30% of components having a molecular weight of 20,000 or more and less than 30,000,
And the molar ratio of maleic acid / (meth) acrylic acid is 50 /
50 to 10/90 (3) 5 to 40% of components having a molecular weight of 10,000 or more and less than 20,000,
And the molar ratio of maleic acid / (meth) acrylic acid is 50 /
50 to 10/90 (4) 15 to 6 components having a molecular weight of 5,000 or more and less than 10,000
0% and the molar ratio of maleic acid / (meth) acrylic acid is 50/50 to 10/90. (5) 10 or more components having a molecular weight of 2,500 or more and less than 5,000
６０60%, and the molar ratio of maleic acid / (meth) acrylic acid is 60 / 40-20 / 80.
４０40%, and the molar ratio of maleic acid / (meth) acrylic acid is 90 / 10-30 / 70 (7) The molar ratio of maleic acid / (meth) acrylic acid is 1-30%, and the component having a molecular weight of 1000 or less is 1%. Is 90/10
The present invention also provides a detergent composition, an inorganic pigment dispersant, and a fiber treating agent containing the maleic acid / (meth) acrylic acid-based copolymer described above.

When the maleic acid / (meth) acrylic acid-based copolymer of the present invention satisfies the following conditions (1 ') to (7'), the viewpoint of calcium ion stability constant and clay adsorption ability is considered. More most preferred.

(1 ') Less than 10% of a component having a molecular weight of 30,000 or more and a maleic acid / (meth) acrylic acid molar ratio of 5
0/50 to 20/80 (2 ') 5 to 15% of a component having a molecular weight of 20,000 or more and less than 30,000, and a molar ratio of maleic acid / (meth) acrylic acid of 50/5.
0-20 / 80 (3 ') 15-40% of components having a molecular weight of 10,000 or more and less than 20,000,
And the molar ratio of maleic acid / (meth) acrylic acid is 50 /
50 to 20/80 (4 ') 15 to 40 components having a molecular weight of 5,000 or more and less than 10,000
%, And the molar ratio of maleic acid / (meth) acrylic acid is 5
0/50 to 20/80 (5 ') A component having a molecular weight of 2,500 or more and less than 5,000
30%, and the molar ratio of maleic acid / (meth) acrylic acid is 60/40 to 20/80 (6 ′).
20%, and the molar ratio of maleic acid / (meth) acrylic acid is 90/10 to 30/70 (7 ′) The component having a molecular weight of 1000 or less is less than 20%, and the molar ratio of maleic acid / (meth) acrylic acid is less than 20%. 90/10
30/70 The maleic acid / (meth) acrylic acid-based copolymer of the present invention is a copolymer obtained by a copolymerization reaction containing maleic acid (salt) and (meth) acrylic acid as monomer components. .

The maleic acid / (meth) acrylic acid-based copolymer of the present invention is not specified by a synthesis method, but is not particularly specified. The copolymer described below obtained by copolymerization in a medium using hydrogen peroxide as a water-soluble polymerization initiator is preferable.

The concentration of maleic acid (salt) at the start of polymerization should be 35% by weight or more for the purpose of improving the polymerizability and controlling the molecular weight distribution of the maleic acid / (meth) acrylic acid copolymer. Is preferred. In order to further achieve the above object, the concentration of maleic acid (salt) at the start of polymerization is more preferably at least 45% by weight, further preferably at least 60% by weight.

The method of charging (meth) acrylic acid (salt) is as follows.
It is preferable that 90% by weight or more of the used amount is charged into the reaction vessel 30 to 500 minutes after the start of the reaction. The remaining less than 10% by weight may be charged into the reaction vessel before the polymerization. If 10% by weight or more of the (meth) acrylic acid (salt) body is added before the reaction, the molecular weight distribution of the obtained maleic acid / (meth) acrylic acid-based copolymer is widened, and the block polymerized nonuniform Since it is a polymer, the clay dispersing ability may decrease.

When (meth) acrylic acid (salt) is introduced in a short time, the molecular weight distribution of the resulting maleic acid / (meth) acrylic acid copolymer becomes narrow, which is preferable for the purpose of controlling the copolymerization ratio. . The charging time of the (meth) acrylic acid (salt) is more preferably 30 to 180 minutes, and the charging time of hydrogen peroxide described later is more preferably 20 to 170 minutes. However, if the charging time of the (meth) acrylic acid (salt) is less than 30 minutes, the amount of maleic acid remaining after the polymerization is increased, or a large amount of reaction heat is released in a short time, making it difficult to remove the heat. Could be

In obtaining the maleic acid / (meth) acrylic acid copolymer of the present invention, it is preferable to use hydrogen peroxide as one of the water-soluble polymerization initiators. The amount of hydrogen peroxide to be used is preferably from the viewpoint of controlling the molecular weight distribution and the copolymerization ratio of the maleic acid / (meth) acrylic acid-based copolymer in which 3 to 20% by weight based on maleic acid (salt) is obtained. If the amount of hydrogen oxide used is less than 3% by weight, the amount of residual maleic acid increases, the molecular weight of the resulting polymer becomes too high, and the clay dispersibility decreases, which is not preferable. From the viewpoint of improving clay dispersibility, it is more preferable to use hydrogen peroxide exceeding 4% by weight. On the other hand, when the use amount of hydrogen peroxide exceeds 20% by weight, it becomes difficult to control the copolymerization ratio and the amount of residual hydrogen peroxide at the end of the polymerization becomes large, causing a problem in safety. Also, if a step of removing the residual hydrogen peroxide is provided, the number of manufacturing steps increases, and the productivity decreases.

Examples of the water-soluble polymerizable initiator which can be used in combination with hydrogen peroxide include persulfates such as ammonium persulfate, sodium persulfate and potassium persulfate; 2,2'-azobis (2-amidinopropane) hydrochloride Azo compounds such as 4,4′-azobis-4-cyanovaleric acid, azobisisobutyronitrile, and 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile); benzoyl peroxide, peroxide Lauroyl, peracetic acid, persuccinic acid, di-tertiary
And organic peroxides such as tert-butyl peroxide, tertiary butyl hydroperoxide, cumene hydroperoxide and the like. As a water-soluble polymerizable initiator which can be used in combination with hydrogen peroxide, one or two selected from these groups
Mixtures of more than one species can be used.

Further, when the supply of hydrogen peroxide is completed 10 to 300 minutes earlier than the completion of the supply of (meth) acrylic acid (salt), the molecular weight distribution of the maleic acid / (meth) acrylic acid (salt) copolymer is optimized. Can be controlled. Under these copolymerization conditions, a specific ratio of the molecular weight fraction can be obtained, and the copolymerization ratio of each molecular weight fraction can be optimally controlled. Also, depending on these copolymerization conditions, the amount of residual maleic acid after completion of the polymerization is 3% by weight or less based on the total amount of the reaction solution, and more preferably 0.3% by weight from the viewpoint of chelating power and dispersing power.
It is better to do the following. When the amount of residual maleic acid exceeds 3% by weight, there is a possibility that a problem such as precipitation of maleic acid crystals may occur in cold winter regions.

As the pH at the time of the polymerization reaction, any pH can be selected, but the pH during the polymerization may be adjusted. Examples of the basic compound for neutralization used for pH adjustment during polymerization include hydroxides and carbonates of alkali metals such as sodium, potassium and lithium; ammonia; monomethylamine;
Alkylamines such as diethylamine, trimethylamine, monoethylamine, dimethylamine and triethylamine; monoethanolamine, diethanolamine,
Triethanolamine, isopropanolamine, second
Alkanolamines such as grade butanolamine; and pyridine. 1 selected from these groups
Species or a mixture of two or more can be used.

The weight average molecular weight of the maleic acid / (meth) acrylic acid copolymer contained in the detergent composition of the present invention is as follows:
It is preferably from 1,000 to 100,000. From the viewpoint of improving the calcium ion stability constant and clay adsorption ability, 2,000 to 50,000 is more preferable,
3,000-30,000 is more preferable, and 5,000
0 to 15,000 is most preferred.

The stability constant of the calcium ion of the maleic acid / (meth) acrylic acid copolymer contained in the detergent composition of the present invention indicates how strongly the calcium ion in water is chelated. Shows that the ability to peel mud stains from fibers is high by peeling off calcium ions present in the fibers. The calcium ion stability constant of the maleic acid / (meth) acrylic acid-based copolymer contained in the detergent composition of the present invention is a numerical value obtained by substituting the numerical value obtained under the following measurement conditions into the following equation 1. (Log
K). (1) Calcium ion solutions of each concentration of 0.002 mol / L, 0.003 mol / L, 0.004 mol / L were prepared (using CaCl ₂ ), and
Pour 50g into 0cc beaker.

(2) 50 mg (in terms of solid content) of the maleic acid copolymer is charged.

(3) Adjust the pH to 10.

(4) 0.15 g of NaCl is added as a calcium ion electrode stabilizer. (5) Measure the free calcium ion concentration using a calcium ion electrode.

Free calcium ion concentration: [Ca] Immobilized calcium ion concentration: [CaS] Number of free chelate sites: [S] Number of chelate sites: [S0] Stability constant: Log K ] [S] / [CaS] = 1 / K [S] =
[S0]-[CaS]. Therefore, [Ca] /
[CaS] = 1 / [S0] · [Ca] + 1 / [S0] · K
Becomes

Therefore, [Ca] / [CaS] is set on the vertical axis, and
[Ca] is plotted on the horizontal axis, and from the slope and intercept, [S
0], K, and Log K were calculated.

The stability constant of the maleic acid / acrylic acid copolymer of the present invention is 4.0 or more, and is 4.2 to 7.0.
Is more preferable from the viewpoint of mud dirt cleaning ability. 4.5-6.
5 is most preferable for the purpose of improving the detergency. If the stability constant is too high, there is no adverse effect on the ability to clean mud stains, but when combined with an enzyme, metal ions in the enzyme may be removed to lower the cleaning power of the enzyme.

The clay-adsorbing ability of the maleic acid / acrylic acid copolymer contained in the detergent composition of the present invention is defined as a numerical value calculated from the value measured by the following measuring method.

Clay adsorption capacity Measurement conditions : Container: 100 cc graduated cylinder Polymer solution: 0.5% (in terms of solid content) 1 cc of aqueous polymer solution + 100 g of tap water (Himeji-shi water) Clay: Amazon clay 1.0 g Stirring time: 10 minutes (Using a magnetic stirrer) Standing time: 18 hours Measurement method: The uppermost 10 cc of the measuring cylinder was sampled, the supernatant was filtered, and the measurement was performed using gel permeation chromatography.

The same measurement was carried out under the above-mentioned measured values and under the condition that clay was not used, and the amount of clay particles adsorbed (clay adsorption ability) was calculated according to the following equation.

Clay adsorption capacity = [area of polymer peak when clay is charged] / [area of polymer peak in system without clay] × 100 (%) By adsorbing maleic acid / (meth) acrylic acid copolymer,
Mud particles have the effect of removing negatively charged and sticky dirt. However, if it is excessively adsorbed, the mud dirt is re-adhered and the cleaning power is reduced. Therefore, those showing the clay adsorption ability in the optimum range as shown below are most suitable for cleaning mud dirt.

40% or more and 60% or less: Clay adsorption ability is most suitable.

30% or more and 70% or less: Clay adsorption ability is very suitable.

20% or more and 90% or less: Clay adsorption ability is suitable.

90% to 95%: 10% to 20% Clay adsorption ability is inappropriate.

95% to 100%: 0 to 10% Clay adsorption ability is extremely inappropriate.

The ability of the maleic acid / (meth) acrylic acid-based copolymer of the present invention to capture calcium ions is defined as the number of mg of calcium ions captured by 1 g of the polymer converted to calcium carbonate. Calcium ion scavenging ability
It is preferably at least 300 mg CaCO ₃ / g (calculated in terms of calcium carbonate captured by 1 g of a maleic acid / acrylic acid copolymer), more preferably 350 mg CaCO ₃ / g.
It is more preferably 380 mg CaCO ₃ / g or more. The higher the calcium ion scavenging ability, the higher the ability as a detergent builder.

The clay dispersing ability of the maleic acid / (meth) acrylic acid copolymer contained in the detergent composition of the present invention is defined by the measured absorbance under the following conditions.

Clay dispersing ability measurement conditions : Container: 100 cc graduated cylinder Polymer solution: 0.5 cc (in terms of solid content) 1 cc of aqueous polymer solution + 100 g of tap water (Himeji-shi water) Clay: Amazon clay 1.0 g Stirring time: 10 minutes (Using magnetic stirrer) Standing time: 18 hours Measurement method: Sample the top 10 cc of the measuring cylinder, measure the absorbance (ABS) at UV 380 nm using a 1 cm cell, and use the value as the clay dispersing ability. .

The clay dispersing ability is an index for judging the effect of removing and dispersing mud stains and the like during washing, and has been revealed to be a very important performance.
In order to obtain such an effect, the clay dispersing ability must be 1.2.
It is necessary to be above. Furthermore, in order to prevent deposition of mud dirt, 1.4 or more is more preferable. Clay dispersibility is the degree of dispersion of clay in the presence of polymer,
It is a numerical value evaluated by the turbidity of the supernatant liquid when the dispersed clay suspension is allowed to stand for a certain period of time. The larger the numerical value, the higher the dispersing ability.

1.4 or more: Very good clay dispersing ability.

1.2 or more to less than 1.4: Good clay dispersing ability.

0.5 or more to less than 1.2: Poor clay dispersing ability.

Less than 0.5 ... Clay dispersing ability is very poor.

The gelling property of the maleic acid / (meth) acrylic acid copolymer contained in the detergent composition of the present invention is defined by the measured absorbance under the following conditions.

Gelability measurement conditions : Container: 500 cc tall beaker Polymer: Test solution 40 ppm (in terms of solid content) Test solution: CaCl ₂ 400 ppm solution 400 g Temperature: 50 ° C. pH: 8 Standing time: 1 hour Measurement method : The solution was stirred for 5 minutes using a stirrer, sampled, and UV3 was filtered using a 50 mm cell.
The absorbance at 80 nm (ABS) is measured.

In general, it has been found that a polymer having a high gelling property is easily insolubilized in a washing liquid, and particularly when high hardness water is used, the detergency is significantly reduced. In order to stably maintain the high-performance detergency of the maleic acid / (meth) acrylic acid-based copolymer contained in the detergent composition, the gelling property is preferably low, and the gelling property is preferably 0.2. It is preferable to set the following.

The gelling property is a numerical value for evaluating the ease of precipitation of a polymer in the presence of calcium ions. The degree of cloudiness when the polymer is heated in the presence of calcium ions is measured by UV absorbance. It is. The larger this number, the greater the turbidity of the polymer solution and the greater the amount of the polymer precipitated in the presence of calcium ions.

Incidentally, calcium ions are present in a large amount in tap water, and a problem of gelation always occurs at the time of precipitation. The index of the gelling property is shown below. The smaller the value below, the higher the performance as a detergent builder.

0.1 or less: Very difficult to gel.

More than 0.1 to 0.2 or less: It is difficult to gel.

More than 0.2 to 0.4 or less: easy to gel.

Exceeding 0.4: Very easy to gel.

The detergent composition containing the maleic acid / (meth) acrylic acid-based copolymer of the present invention can be used in combination with a surfactant and, if necessary, an enzyme.

As the surfactant, an anionic surfactant, a nonionic surfactant, an amphoteric surfactant and a cationic surfactant can be preferably used.

Examples of the anionic surfactant include alkyl benzene sulfonate, alkyl or alkenyl ether sulfate, alkyl or alkenyl sulfate,
α-olefin sulfonate, α-sulfo fatty acid or ester salt, alkane sulfonate, saturated or unsaturated fatty acid salt, alkyl or alkenyl ether carboxylate, amino acid type surfactant, N-acyl amino acid type surfactant, Examples thereof include an alkyl or alkenyl phosphate or a salt thereof.

Examples of the nonionic surfactant include polyoxyalkylene alkyl or alkenyl ether, polyoxyethylene alkyl phenyl ether, higher fatty acid alkanolamide or an alkylene oxide adduct thereof, sucrose fatty acid ester, alkyl glycooxide, and fatty acid glycerin monoester. Examples thereof include esters and alkylamine oxides.

Examples of the amphoteric surfactant include carboxy type or sulfobetaine type amphoteric surfactants, and examples of the cationic surfactant include quaternary ammonium salts.

The content of these surfactants is from 5 to 70
% By weight, and more preferably 20 to 60% by weight.

As the enzyme to be added to the detergent composition containing the maleic acid / (meth) acrylic acid copolymer of the present invention, protease, lipase, cellulase and the like can be used. Particularly, protease, alkaline lipase, alkaline cellulase and the like having high activity in an alkaline washing solution are preferable. The amount of the enzyme is 0.01 to 5% by weight.
Is preferred. If the ratio is out of this range, the balance with the surfactant is lost, and the cleaning power cannot be improved.

The detergent composition containing the maleic acid / (meth) acrylic acid copolymer of the present invention may contain, if necessary, a known alkali builder, chelate builder, anti-redeposition agent, fluorescent agent, bleaching agent, Components commonly used in detergent compositions such as fragrances may be blended. Further, zeolite may be blended. Silicates, carbonates, sulfates and the like can be used as the alkali builder. Chelate builders include diglycolic acid, oxycarboxylate, EDTA
(Ethylenediaminetetraacetic acid), DTPA (diethylenetriaminehexaacetic acid), citric acid and the like can be used as needed.

The maleic acid (salt) used for obtaining the maleic acid / (meth) acrylic acid copolymer of the present invention is:
Any type of maleic acid, maleic acid mono-alkali metal salt and maleic acid dialkali metal salt may be introduced into the reaction vessel, or one or a mixture of two or more of these may be used. The maleic acid may be a product obtained by hydrolyzing maleic anhydride in a reaction vessel, and the mono-alkali metal salt of maleic acid and the dialkali metal salt of maleic acid may be obtained by treating maleic acid and / or maleic anhydride in a reaction vessel.
It may be obtained by reacting with an alkali metal hydroxide.

The fiber treating agent of the present invention comprises the maleic acid copolymer of the present invention and at least one selected from the group consisting of a dye, a peroxide and a surfactant. It can be used in scouring, dyeing, bleaching and soaping processes. Dyes, peroxides and surfactants include those commonly used in fiber treatments. Maleic acid-based copolymer, dye,
The ratio with at least one selected from the group consisting of a peroxide and a surfactant may be, for example, 1 part by weight of a maleic acid-based copolymer in order to improve the whiteness of the fiber, uneven color, and the degree of dyeing. To at least one selected from the group consisting of dyes, peroxides and surfactants
-100 parts by weight. The fibers for which the fiber treating agent of the present invention can be used are not particularly limited. Examples thereof include cellulosic fibers such as cotton and hemp; chemical fibers such as nylon and polyester; animal fibers such as wool and silk; and semi-synthetic materials such as human silk. Fibers and their fabrics and blends.

When the fiber treating agent of the present invention is applied to the scouring step, it is preferable to blend the maleic acid-based copolymer of the present invention, an alkali agent and a surfactant. When applied to the bleaching step, it is preferable to blend the maleic acid-based copolymer of the present invention, a peroxide, and a silicate-based agent such as sodium silicate as a decomposition inhibitor of an alkaline bleaching agent.

[0072]

The maleic acid / (meth) acrylic acid-based copolymer of the present invention has a specific ratio between the molecular weight cut-off of a specific ratio and the copolymerization ratio of each molecular weight-fractionated component. It has very good physical properties in all of ion trapping ability, clay dispersing ability, clay particle adsorbing ability and gelling ability. When used as a detergent composition, these properties are important properties for enhancing the detergency, and include dispersing action of mud dirt, action of preventing re-adhesion, and prevention of gelation by surfactant calcium ions. This greatly improves the cleaning power. Also inorganic pigment dispersant,
It is also an important basic physical property as a fiber treatment agent.

The maleic acid / (meth) acrylic acid copolymer of the present invention is obtained by copolymerizing maleic acid (salt) and (meth) acrylic acid (salt) in an aqueous medium. Is less than 2% by weight based on the total amount of the reaction solution, and the amount of residual maleic acid is 3% by weight based on the total amount of the reaction solution.
If the product is obtained by isolating from the following copolymerization reaction solution, the concentration of hydrogen peroxide and the amount of residual maleic acid in the maleic acid / (meth) acrylic acid-based copolymer obtained after the isolation Will be lower. Furthermore, the amount of hydrogen peroxide in the reaction solution can be reduced as much as possible at the end of the polymerization by terminating hydrogen peroxide earlier than (meth) acrylic acid (salt). In addition, a polymer having a narrow molecular weight distribution is obtained, and the gelling property is reduced. If the introduction of the (meth) acrylic acid (salt) -based monomer is performed in such a short time that the reaction does not run away, the reaction efficiency of the entire polymerization reaction can be increased. In addition, by allowing the polyvalent metal ion to be present in the polymerization reaction system, maleic acid remaining in the reaction solution can be sufficiently suppressed at the time of completion of the polymerization, and the reaction efficiency is increased.

By introducing the (meth) acrylic acid (salt) monomer in such a short time that the reaction does not run away, the molecular weight distribution of the resulting maleic acid / (meth) acrylic acid copolymer is reduced. Narrower, clay dispersing power becomes higher,
Gelling properties also decrease. When the pH at the start of the polymerization is set to 2 or less, and the pH is increased with the progress of the polymerization and the degree of neutralization during the polymerization is maintained at less than 20%, the obtained maleic acid / The molecular weight distribution of the (meth) acrylic acid-based copolymer is narrowed, the clay dispersibility is increased, and the gelling property is also reduced.

The maleic acid-based copolymer obtained by the production method of the present invention has excellent performance as described above, and has a small amount of residual initiator and residual monomer. Agent, water treatment agent and fiber treatment agent.

[0076]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples. Note that “%” and “parts” indicate “% by weight” and “parts by weight”, respectively.

(Production Example 1) 196 parts of maleic anhydride (232 parts as maleic acid), 110.7 parts of deionized water, water in a 1-liter four-necked flask equipped with a thermometer, a stirrer and a reflux condenser 48% aqueous solution of sodium oxide 3
After charging 33.3 parts (concentration of the initial solid content of 50%), the aqueous solution was heated to the boiling temperature under normal pressure while stirring. Next, 75.5 parts of 35% hydrogen peroxide solution (8.26% by weight of maleic acid (salt) (A)) was continuously added dropwise with stirring over 90 minutes from the start of polymerization, and 80% acrylic acid was added. 270.38 parts of an aqueous solution (maleic acid / acrylic acid = 4/6 molar ratio) were continuously added dropwise over 140 minutes to complete the polymerization reaction. (Monomer concentration at the start of polymerization: 50
%) The ratio of the molecular weight cut-off, the weight average molecular weight and the amount of residual maleic acid of the obtained copolymer (1) were measured using gel permeation chromatography, and the results are shown in Table 3. The column is Asahi Kasei Asahi Pack GFA
-7 MF was used, and a 0.5% phosphoric acid aqueous solution was used as an eluent. As a molecular weight standard sample, a sodium polyacrylate standard sample (manufactured by Sou Kagaku Co., Ltd.) was used.

The maleic acid / methacrylic acid ratio of each of the molecular weight cutoffs of the maleic acid / (meth) acrylic acid-based copolymer of the present invention was determined by the following measurement conditions: Quantification was performed by

Separation conditions for each molecular weight cut-off (using dialysis membrane) (1) Maleic acid / (meth) acrylic acid type copolymer
Adjust the wt% aqueous solution. (2) Prepare a dialysis membrane (Spectra / Pore 6 (MWCO: 1000), Ieda Trading), and (1)
Of 50 g of the above solution.

(3) Take 800 g of pure water into a 1 L beaker, and put the dialysis membrane containing the solution prepared in (2) into it. Pure water in beaker is 3hr, 12hr, 24h
Replace with 800 g of fresh water for each of r, 48 hr and 72 hr.

(4) Separation was performed under the conditions described below, and the sample was concentrated and dried, and then the ratio of maleic acid / (meth) acrylic acid was measured using proton NMR.

The results are shown in Table 2.

The sample solution is a dialysis membrane internal solution having a molecular weight of 30,000 or more and 96 hours.

A dialysis membrane external solution after a molecular weight of 20,000 or more and less than 30,000 for 96 hours is used as a sample.

The dialysis membrane external solution after a molecular weight of 10,000 or more and less than 20,000 for 72 hours is used as a sample.

The dialysis membrane external solution after 48 hours of a molecular weight of 5,000 or more and less than 10,000 is used as a sample.

The dialysis membrane external solution after a molecular weight of 2500 or more and less than 5000 for 24 hours is used as a sample.

The sample solution is a dialysis membrane external solution after a lapse of 12 hours from a molecular weight of more than 1,000 and less than 2500.

The molecular weight is 1000 or less. The dialysis membrane external solution after 3 hours has passed is used as a sample.

The stability constant of calcium ion of the maleic acid copolymer contained in the detergent composition of the present invention is defined as a numerical value obtained by substituting a numerical value obtained under the following measurement conditions into the following equation 1. Is performed. (1) Calcium ion solutions of each concentration of 0.002 mol / L, 0.003 mol / L and 0.004 mol / L were prepared (using CaCl 2)
Pour 50g into 0cc beaker.

(2) 50 mg (in terms of solid content) of the maleic acid copolymer is charged.

(3) Adjust the pH to 10.

(4) 0.15 g of NaCl is added as a calcium ion electrode stabilizer.

(5) Using a calcium ion electrode, the concentration of free calcium ions is measured.

Free calcium ion concentration: [Ca] Immobilized calcium ion concentration: [CaS] Free chelate sites: [S] Number of chelate sites: [S0] Stability constant: Log K, [Ca] [S] /
[CaS] = 1 / K [S] = [S0]-[CaS]. Therefore, [Ca] / [CaS] = 1 / S0 · [C
a] + 1 / [S0] · K.

Therefore, [Ca] / [CaS] is set on the vertical axis, and
[Ca] is plotted on the horizontal axis, and [S] is calculated from the slope and the intercept.
0], K, and Log K were calculated.

The clay adsorption capacity of the maleic acid-based copolymer contained in the detergent composition of the present invention is defined as a numerical value calculated from the value measured by the following measurement method.

Clay adsorption capacity Measurement conditions : Container: 100 cc graduated cylinder Polymer solution: 0.5% (in terms of solid content) 1 cc of aqueous polymer solution + 100 g of tap water (Himeji city water) Clay: Amazon clay 1.0 g Stirring time: 10 minutes (Using a magnetic stirrer) Standing time: 18 hours Measurement method: The uppermost 10 cc of the measuring cylinder was sampled, the supernatant was filtered, and the measurement was performed using the gel permeation chromatography described above.

The same measurement was carried out under the above-mentioned measured values and under the above-mentioned conditions without clay, and the amount of adsorption (clay adsorption ability) on clay particles was calculated according to the following equation.

Amount of clay adsorption capacity = [area of polymer peak when clay is charged] / [area of polymer peak in system without clay] × 100 (%) 40% or more and 60% or less: Clay adsorption ability is most suitable ing.

30% or more and 70% or less: Clay adsorption ability is very suitable.

20% or more and 90% or less: Clay adsorption ability is suitable.

90% to 95%: 10% to 20% Clay adsorption ability is inappropriate.

95% to 100%: 0 to 10% Clay adsorption ability is extremely inappropriate.

The polymer was added to the aqueous solution of calcium carbonate prepared under the following conditions and stirred under the following conditions, and the calcium ion concentration in the aqueous solution of calcium carbonate before and after the stirring was measured using an ion analyzer (Elo, manufactured by Orion).
A920) using Orion calcium electrode (93-
20), and from the concentration difference before and after stirring, the amount of calcium ions captured by the polymer is calculated in terms of calcium carbonate.
g of the polymer, and that value was taken as the calcium ion trapping ability of this polymer.

Conditions for measuring calcium ion trapping ability : Container: 100 cc beaker Liquid: Ca ²⁺ 1.0 × 10 ⁻³ mol / l aqueous solution 50 cc Polymer: 10 mg (in terms of solid content) Temperature: 25 ° C. Stirring time: 10 minutes (stirrer) Use) Clay is added to the polymer solution prepared under the following conditions,
With the absorbance measured after stirring and standing,
The clay dispersing power of this polymer was used. The higher the number,
It means that clay dispersibility is high.

Clay dispersing ability measurement conditions : Container: 100 cc graduated cylinder Polymer solution: 0.5% (in terms of solid content) 1 cc of aqueous polymer solution + 100 g of tap water (Himeji city water) Clay: Amazon clay 1.0 g Stirring time: 10 minutes (Using magnetic stirrer) Standing time: 18 hours Measurement method: Absorbance (ABS) at UV 380 nm was measured using a 1 cm cell by sampling the top 10 cc of the measuring cylinder, and the numerical value was used as the clay dispersing ability. .

A polymer was added to a CaCl ₂ test solution prepared under the following conditions and gelled under the following conditions, and the absorbance of the test solution was measured.
The gelability of this polymer was determined. The larger the value, the higher the gelling property.

Gelability measurement conditions : Container: 500 cc tall beaker Polymer: Test solution 40 ppm (in terms of solid content) Test solution: CaCl ₂ 400 ppm solution 400 g Temperature: 50 ° C. pH: 8 Standing time: 1 hour Measurement method : The solution was stirred for 5 minutes using a stirrer, sampled, and UV3 was filtered using a 50 mm cell.
The absorbance at 80 nm (ABS) was measured.

The results are shown in Table 3.

(Production Example 2) Except that 13.3 parts (1 g / 1 mol of charged monomer) of a 15% aqueous sodium persulfate solution was continuously dropped from 90 minutes to 140 minutes after the initiation of polymerization, a production example was carried out. Polymerization was carried out in exactly the same manner as in Example 1, and analysis was carried out in the same manner as in Production Example 1. The results are shown in Tables 2 and 3. (Monomer concentration at the start of polymerization: 50%) (Production Examples 3 to 5) Except for using the monomers described in Table 1 in the amounts described in Table 1 in place of the 80% aqueous acrylic acid solution, exactly the same as in Production Example 1 was used. Polymerization was carried out, and analysis was carried out in the same manner as in Production Example 1. The results are shown in Tables 2 and 3. (Monomer concentration at the start of polymerization: 50%) (Production Examples 6 to 8) 13.3 parts of a 15% aqueous sodium persulfate solution was used from 90 minutes after the start of polymerization by using an aqueous 80% acrylic acid solution in an amount shown in Table 4. Polymerization was carried out in exactly the same manner as in Production Example 1 except that the solution was continuously dropped over a period of minutes, and analyzed in the same manner as in Production Example 1. The results are shown in Tables 2 and 3. (Monomer concentration 50% at the start of polymerization) (Production Example 9)
And polymerization was conducted in the same manner as in Production Example 1, except that 0.08 part of ferrous ammonium sulfate hexahydrate was charged. It was shown to. (Monomer concentration at initiation of polymerization: 68.7%) (Comparative Production Examples 1 and 2 (Influence of hydrogen peroxide amount)) Production Example 1
The polymerization was carried out in exactly the same manner as in Production Example 1 except that the amount of the 35% hydrogen peroxide used in Table 3 was continuously dropped over 140 minutes from the start of the polymerization. The analysis was performed similarly. The results are shown in Tables 5 and 6. (Monomer concentration at the start of polymerization: 50%) (Comparative Production Example 3) In Production Example 1, the amount of the 60% aqueous solution of acrylic acid was changed to 7,760 parts, and 500 parts of deionized water was simultaneously used.
0 parts and 887.7 parts of a 15% aqueous sodium persulfate solution (2
g / prepared monomer) was polymerized in exactly the same manner as in Production Example 1 except that it was continuously dropped over 150 minutes, and the analysis was carried out as in Production Example 1. Tables 5 and 6 show the results.
It was shown to. (Monomer concentration at the start of polymerization: 50%) (Comparative Production Example 4) Production Example 1 was the same as Production Example 1 except that the amount of the 60% aqueous acrylic acid solution was changed as shown in Table 4.
The polymerization was carried out in exactly the same manner as described above, and the analysis was carried out in the same manner as in Production Example 1. The results are shown in Tables 5 and 6. (50% monomer concentration at the start of polymerization)

[0112]

[Table 1]

[0113]

[Table 2]

[0114]

[Table 3]

[0115]

[Table 4]

[0116]

[Table 5]

[0117]

[Table 6]

(Examples 1 to 9) Maleic acid type / (meth)
In order to evaluate the performance of the acrylic acid-based copolymer as a detergent composition, the following detergency test was performed.

The artificial soil shown in Table 7 was dispersed in carbon tetrachloride, and a cotton white cloth was passed through an artificial soil liquid, dried and cut to prepare a 10 cm × 10 cm soiled cloth.

[0120]

[Table 7]

The detergent compositions shown in Table 8 were blended and washed under the conditions shown in Table 9. After washing and drying the cloth, the reflectance was measured.

[0122]

[Table 8]

[0123]

[Table 9]

The cleaning rate was determined from the reflectance according to the following equation, and the cleaning performance was evaluated. The results are shown in Table 10.

Cleaning rate = (reflectance after cleaning−reflectance before cleaning) / (reflectance of white cloth−reflectance before cleaning) × 100 (Comparative Examples 1 to 4) Comparative maleic acid / (meth) acrylic acid The cleaning rate was measured by the method described in Examples 1 to 25 using the system copolymers (1) to (4). The results are shown in Table 11.

[0126]

[Table 10]

[0127]

[Table 11]

(Examples 10 to 18) (Evaluation as fiber treatment agent) Maleic acid / (meth) acrylic acid copolymers (1) to
In order to evaluate the performance as a fiber treatment agent of (9), a fiber bleaching test shown below was performed.

Using a maleic acid copolymer at 2 g / L as a fiber treatment agent, a scoured cotton sheet knit was bleached under the following conditions. Table 12 shows the results.

(Bleaching conditions) Hardness of used water 35. DH bath ratio 1:25 Temperature 85 ° C Time 30 minutes Chemical used Hydrogen peroxide 10 g / L Sodium hydroxide 2 g / L No. 3 sodium silicate 5 g / L ( (Evaluation) The texture of the treated cloth was determined by a sensory test.

The whiteness was measured using a 3M color computer model SM-3 manufactured by Suga Test Instruments Co., Ltd., and the whiteness equation of Lab system W = 100 − [(100−L) ² + a ² + b ² ] ^1/2, where L = measured lightness a = measured chromaticity index b = measured chromaticity index Whiteness (W) was determined and evaluated.

The sewing performance was evaluated by the number of broken ground yarns when four cloths were piled up and 30 cm of empty sewing was performed with a lockstitch sewing machine using a needle # 11S.

(Comparative Examples 5 to 8) Bleaching tests of fibers were carried out using the comparative maleic acid / (meth) acrylic acid copolymers (1) to (4) according to the methods described in Examples 10 to 18. went. Table 13 shows the results.

[0134]

[Table 12]

[0135]

[Table 13]

(Examples 19 to 27) (Evaluation as Inorganic Pigment Dispersant) Maleic acid / (meth) acrylic acid copolymers (1) to
In order to evaluate the performance of (9) as an inorganic pigment dispersant,
The following tests were performed.

Capacity 1L (Material SUS 304, inner diameter 90
In a beaker 160 mm in height and 160 mm in height, a calcite-based cubic light calcium carbonate (primary particle diameter 0.15 μm) filter press dewatered cake (solid content 65.3%) 40
0 parts, and as a dispersant, 3.26 parts of a 40% aqueous solution of a maleic acid-based copolymer (0.5% of a water-soluble polymer based on the weight of calcium carbonate) and water for adjusting the solid content concentration Add 6.9 parts and dissolver stirring blade (50mm
(φ) and kneaded at low speed for 3 minutes. Thereafter, the mixture was dispersed at 3000 rpm for 10 minutes to obtain an aqueous dispersion having a solid content of 64%.
The viscosities of the resulting aqueous dispersion immediately after dispersion and after standing at room temperature for one week were measured at 25 ° C. using a B-type viscometer to test the stability over time. Table 14 shows the measurement results.

(Comparative Examples 9 to 12) Comparative maleic acid / (meth) acrylic acid copolymers (1) to (4) were used to prepare aqueous dispersions according to the methods described in Examples 19 to 27. A daily stability test was performed. Table 15 shows the measurement results.

[0139]

[Table 14]

[0140]

[Table 15]

[0141]

The detergent composition containing the maleic acid / (meth) acrylic acid-based copolymer of the present invention has a specific molecular weight cut-off ratio and a specific copolymerization ratio for each molecular weight cut-off. It is possible to provide a detergent composition, an inorganic pigment dispersant, and a fiber treating agent having high calcium ion trapping ability, good clay dispersing ability, and a balance of properties with low gelling properties. In particular, conventional detergent compositions containing maleic acid-based copolymers having high gelling properties, inorganic pigment dispersants, and fiber treatment agents tend to be insolubilized in the water used, so their performance deteriorates especially when high-hardness water is used. Is remarkable. In order to overcome these problems and maintain stable high performance,
A maleic acid-based copolymer with low gelling property is required,
This is achieved for the first time by the maleic acid / (meth) acrylic acid-based copolymer of the present invention.

The maleic acid / (meth) acrylic acid-based polymer of the present invention can be suitably used especially as a detergent for clothing. In addition, a trace amount of metal in the cleaning solution, for example, iron ions, zinc ions, etc., to prevent yellowing of the fiber, the specific calcium ion trapping ability obtained in the present invention, a maleic acid-based copolymer having gelling properties Very effective.
The reason that such a high-performance maleic acid / (meth) acrylic acid-based polymer copolymer was found was that a polymerization method using a large amount of hydrogen peroxide as a polymerization initiator was adopted in the first half.

Although it is not clear why a high-performance maleic acid / (meth) acrylic acid copolymer was obtained by this polymerization method, maleic acid could be uniformly introduced into the high molecular weight portion of the polymer. It is presumed that the amount of the low molecular weight polymer could be reduced and a polymer having a narrow molecular weight distribution was obtained.

Continuation of the front page (56) References JP-A-52-4510 (JP, A) JP-A-57-168906 (JP, A) JP-A-60-212412 (JP, A) JP-A-61-126104 (JP, A) JP-A-3-124711 (JP, A) JP-A-7-291169 (JP, A) JP-A-7-316999 (JP, A) JP-A 8-41109 (JP, A) International publication 95 / 33815 (WO, A1) WO 96/18714 (WO, A1) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08F 220/00-220/70 C08F 20/00-20/70 B01F 17/00-17/56 C08F 222/00-222/40 C08F 22/00-22/40 C11D 3/00-3/60 D06M 15/00-15/715

Claims (4)

(57) [Claims] 1. A maleic acid / (meth) acrylic acid-based copolymer, wherein the molecular weight cut off using a gel permeation chromatogram satisfies the following conditions (1) to (7): . (1) Less than 20% of a component having a molecular weight of 30,000 or more and a maleic acid / (meth) acrylic acid molar ratio of 50/50 to 1
0/90 (2) 1 to 30% of components having a molecular weight of 20,000 or more and less than 30,000,
And the molar ratio of maleic acid / (meth) acrylic acid is 50 /
50 to 10/90 (3) 5 to 40% of components having a molecular weight of 10,000 or more and less than 20,000,
And the molar ratio of maleic acid / (meth) acrylic acid is 50 /
50 to 10/90 (4) 15 to 6 components having a molecular weight of 5,000 or more and less than 10,000
0% and the molar ratio of maleic acid / (meth) acrylic acid is 50/50 to 10/90. (5) 10 or more components having a molecular weight of 2,500 or more and less than 5,000
６０60%, and the molar ratio of maleic acid / (meth) acrylic acid is 60 / 40-20 / 80.
４０40%, and the molar ratio of maleic acid / (meth) acrylic acid is 90 / 10-30 / 70 (7) The molar ratio of maleic acid / (meth) acrylic acid is 1-30%, and the component having a molecular weight of 1000 or less is 1%. Is 90/10
~ 30/70 2. A detergent composition comprising the copolymer according to claim 1 or 2. 3. An inorganic pigment dispersant comprising the copolymer according to claim 1 or 2. 4. A fiber treating agent comprising the copolymer according to claim 1 or 2.