JPH08208770A - Water-soluble graft polymer and preparation and application thereof - Google Patents

Abstract

PURPOSE: To prepare a water-soluble graft polymer which, when incorporated into a surfactant, can provide a detergent compsn. possessing excellent detergency by grafting a plurality of predetermined compds. onto a polyether compd. to impart particular properties. CONSTITUTION: 25 to 40wt.%, based on a polyether compd., monomer component comprising pref. 50 to 80mol.% (meth)acrylic acid and pref. 20 to 50mol.% ethylenically unsatd. dicarboxylic acid monomer (e.g. maleic acid) is grafted onto a polyether compd. having a number-average mol.wt. of 250 to 1900, with not less than 80mol.% ethylene oxide being pref. present as the constituent unit, to bring a Ca ion trapping capacity to 40 to 130mg CaCO3 /g and the gelation resistance to not more than 1.5.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a polyether containing ethylene oxide as a main component, an ethylenically unsaturated monomer containing (meth) acrylic acid as a main component, and an ethylenically unsaturated dicarboxylic acid type such as maleic acid. Monomer is grafted, and calcium ion trapping ability is 40 ~ 130mgCaC
The present invention relates to a water-soluble graft polymer having O ₃ / g and a gelation resistance of 1.5 or less.

The present invention also relates to a method for producing a water-soluble graft polymer.

Further, the present invention relates to a detergent composition containing a specific water-soluble graft polymer and a surfactant.

[0004]

2. Description of the Related Art Attempts to graft-polymerize (meth) acrylic acid on a polyether compound have been made up to now in various fields of application such as polyurethane. For example, JP-A-5
In Japanese Patent Publication No. 5-71710, 3 to 15 w is added to the total charged amount.
A polymer obtained by graft-polymerizing t% acrylic acid on a polyoxyalkylene compound and a method for producing the same are disclosed.
However, in this case, when the obtained graft polymer is used as a dispersant such as a detergent builder or an inorganic pigment, a fiber treatment agent, etc., the amount of carboxylic acid is small and the calcium ion-capturing ability is too low, which is satisfactory. It does not give good performance, or a very large amount of addition is necessary for good performance.

Further, in JP-A-59-62614, at least 20 wt% based on the graft polymer is added to a polyglycol ether having at least one hydrophobic group.
In the graft polymer obtained by graft-polymerizing the hydrophilic ethylenically unsaturated monomer and the method for producing the same, a method using a solvent of water or toluene, or a method in which the reaction temperature is 90 ° C. or lower without a solvent is disclosed. There is. The graft efficiency of the graft polymer obtained by this method is low, there are many ungrafted polymers, and the gelation resistance is poor, so this graft polymer was used as a dispersant for detergent builders and inorganic pigments. In this case, satisfactory performance is not obtained, and when used as a builder for a liquid detergent, there is a problem that the polymer is separated.

Further, JP-A-3-177406 also discloses a similar graft polymer obtained by polymerization in an aqueous solvent. However, the disclosed polymerization method of graft polymerization in an aqueous solvent has poor grafting efficiency, and many of the obtained polymers are polycarboxylic acids which have not been grafted, and thus have poor gelation resistance and are used in the above applications. When doing so, there is a problem that the desired performance cannot be obtained.

As described above, according to the prior art, an ungrafted polymer having an optimum calcium ion-capturing ability in a specific range and a good gelation resistance, a large detergency improving effect and a high grafting efficiency. It was not possible to easily prepare a graft polymer having a small amount of styrene.

[0008]

DISCLOSURE OF THE INVENTION The present invention provides a polyether containing a monoethylenically unsaturated monomer mainly composed of (meth) acrylic acid and an ethylenically unsaturated dicarboxylic acid monomer in a high content. It is a water-soluble graft polymer that is highly grafted and has a high graft ratio, and shows very good performance when used as a detergent builder or scale inhibitor by exhibiting a specific range of calcium ion trapping ability and a specific range of gelation resistance. It is an object of the present invention to provide a united body and a manufacturing method thereof. Another object of the present invention is to provide a detergent composition having a greatly improved detergency by containing the water-soluble graft polymer.

[0009]

[Means for Solving the Problems] The present inventors have used the above-mentioned problems as detergent builder and scale inhibitor by improving the above-mentioned problems and exhibiting a specific range of calcium ion-trapping ability and a specific range of gelation resistance. In this case, as a result of intensive studies on a water-soluble graft polymer exhibiting extremely good performance and a method for producing the same, the present invention has been completed.

That is, according to the present invention, a polyether compound is grafted with (meth) acrylic acid and an ethylenically unsaturated dicarboxylic acid type monomer, and has a calcium ion-trapping ability of 40 to 130 mg CaCO ₃ / g and gelation resistance. A water-soluble graft polymer having a property of 1.5 or less.

In addition, the present invention uses 80% ethylene oxide.
Number average molecular weight of 250 having mol% or more as a constituent unit
In the polyether compound (A) of 1900 or less, (meth) acrylic acid (b1) 50 to 80 mol% and ethylenically unsaturated dicarboxylic acid monomer (b2) 20 to 50 mo
The present invention relates to a method for producing a water-soluble graft polymer, which comprises graft-polymerizing 1% of a monomer component (B) with respect to a polyether compound (A) in an amount of 25-40 wt%.

The present invention further relates to a detergent composition containing a specific water-soluble graft polymer and a surfactant.

The polyether compound (A) used in the present invention has a number average molecular weight of 250 or more and 1900 or less having ethylene oxide as a constituent unit of 80 mol% or more, and ethylene oxide and other alkylene oxides are mixed with water or water. It is obtained by polymerizing by a known method using alcohol as a starting point. Examples of the alcohol for obtaining the polyether include primary alcohols having 1 to 22 carbon atoms such as methanol, ethanol, n-propanol, and n-butanol; secondary alcohols having 3 to 18 carbon atoms; and 3 such as t-butanol. Grade alcohol;
Examples include diols such as ethylene glycol, diethylene glycol, propanediol, butanediol, and propylene glycol; triols such as glycerin and trimethylolpropane; polyols such as sorbitol. Other alkylene oxides copolymerizable with ethylene oxide are not particularly limited, but propylene oxide and butylene oxide are preferable. Further, other alkylene oxide copolymerizable with ethylene oxide must be less than 20 mol% as a whole.
When it is 20 mol% or more, the graft ratio of the obtained graft polymer is lowered. Further, as the polyether compound (A), the hydroxyl groups at all or some of the terminals of the polyether obtained as described above have 2 carbon atoms.
Also, those obtained by esterification with a dicarboxylic acid such as fatty acid No. 22 to 22, succinic acid, succinic acid anhydride, maleic acid, maleic acid anhydride, and adipic acid can be mentioned.

The molecular weight of these polyethers is 2
50 or more and 1900 or less, preferably 300 or more 1
It is 500 or less, more preferably 400 or more and 1300 or less. When the molecular weight is less than 250, the graft ratio is lowered and the gelation property is deteriorated. On the other hand, when the molecular weight exceeds 1900, there is a problem that the gelation resistance is deteriorated and the calcium ion capturing ability is significantly reduced.

The gel resistance of the graft polymer of the present invention is
It is 1.5 or less. If the gel resistance exceeds 1.5,
Due to the effect of calcium ions in water, the graft polymer
It tends to be insoluble, and the performance when used as a detergent builder, scale inhibitor, etc. is greatly reduced. Gel resistance is 1.
0 or less is preferable, 0.5 or less is more preferable, and 0.3
The range of 0.1 or more is most preferable.

The calcium ion-capturing ability of the graft polymer of the present invention is 40 to 130, which is a numerical value in which the amount of calcium ions captured per 1 g of the polymer is represented by mg in terms of calcium carbonate. When it is less than 40, the performance when used as a detergent builder, a fiber treatment agent, etc. is significantly reduced. If it exceeds 130, gel resistance is deteriorated, which is not preferable. The calcium ion-capturing ability is 60 to 120,
80-115 are the most preferable.

The graft polymer of the present invention comprises, for example, a polyether compound (A) and (meth) acrylic acid (b1) 50.
Use of the monomer component (B) consisting of ˜80 mol% and the ethylenically unsaturated dicarboxylic acid type monomer (b2) 20 to 50 mol% in an amount of 25 to 40 wt% with respect to 100 wt% of the polyether compound (A). It is obtained by graft polymerization in an amount.

Among the monomer components (B), acrylic acid is used as the component (b1), and the polyether compound (A) 100w
It is more preferable to perform graft polymerization in an amount of 25 to 30 wt% with respect to t%. If it is less than 25 wt%, the density of the carboxylic acid of the obtained graft polymer is low, and various performances such as calcium ion trapping ability and dispersing ability are not satisfied.

Examples of the ethylenically unsaturated dicarboxylic acid type monomer (b2) include maleic acid; fumaric acid; maleic anhydride; alkyl esters of maleic acid such as dimethyl maleate and diethyl maleate; dimethyl fumarate. Examples thereof include alkyl fumaric acid esters such as diethyl fumarate, and one or more of them can be used. Among these, maleic acid, fumaric acid, and maleic anhydride are preferable from the viewpoint of increasing the carboxylic acid density of the graft polymer and enhancing the calcium ion capturing ability and the dispersing ability.

The (meth) acrylic acid (b1) and the ethylenically unsaturated dicarboxylic acid type monomer (b2) are added to at least one selected from the group consisting of maleic acid, fumaric acid and maleic anhydride.
If one is used, half or more of (b2) is mixed in advance with the polyether compound (A), and then the remaining monomer component (B)
And it is particularly preferable to add a polymerization initiator and perform graft polymerization. By this method, the introduction rate of maleic acid, fumaric acid, and maleic anhydride into the graft polymer can be significantly improved.

The copolymerization ratio of the (meth) acrylic acid (b1) and the ethylenically unsaturated dicarboxylic acid type monomer (b2) is
(B1) is 50-80 mol%, (b2) is 20-50mo
1%. The copolymerization ratio is such that (b1) is 60 to 75 mol.
%, And the monomer (b2) is preferably 25 to 40 mol% for the purpose of improving gelation resistance and optimizing calcium ion-capturing ability.

If the content of (meth) acrylic acid is less than 50 mol%, the dispersibility of the resulting graft polymer will not be satisfactory and the amount of residual monomer will increase, which is not preferable. When the content of (meth) acrylic acid is 80 mol% or more, gelation resistance is deteriorated, which is not preferable.

Graft polymerization is carried out in the presence of a polymerization initiator.
It is carried out substantially without solvent. As the polymerization initiator, a known radical initiator can be used,
Organic peroxides are particularly preferred.

Examples of organic peroxides include ketone peroxides such as methyl ethyl ketone peroxide and cyclohexanone peroxide; t-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, p-menthane hydroperoxide, and 2 , 5-dimethylhexane-2,5-dihydroperoxide, 1,1,3,3
-Hydroperoxides such as tetramethylbutyl hydroperoxide; di-t-butyl peroxide, t-butylcumyl peroxide, dicumyl peroxide, α, α'-bis (t-butylperoxy) p
-Dialkyl peroxides such as diisopropylbenzene, α, α'-bis (t-butylperoxy) p-diisopropylhexyne; t-butylperoxyacetate, t-butylperoxylaurate, t-butylperoxybenzoate , Di-t-butylperoxyisophthalate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, peroxyesters such as t-butylperoxyisopropyl carbonate; n-butyl-4,4 Examples include peroxyketals such as -bis (t-butylperoxy) valeate and 2,2-bis (t-butylperoxy) butane; diacyl peroxides such as dibenzoyl peroxide.

The amount of the polymerization initiator is not particularly limited, but is preferably 0.1 to the monoethylenically unsaturated monomer.
15% by weight, more preferably 0.5 to 10% by weight is used. If it is less or more than this, the grafting efficiency of the monomer to the polyether is lowered. Further, the polymerization initiator can be added to the polyether in advance,
It can also be added at the same time as the monoethylenically unsaturated monomer.

The graft polymerization is preferably carried out substantially without solvent. When water or an organic solvent such as alcohol or toluene is used, the efficiency of grafting the monomer to the polyether is lowered. When a solvent is used for adding an initiator and a monomer, the amount thereof is preferably as small as possible, preferably 5 wt% or less based on the total amount, or the solvent is preferably distilled off immediately after the addition.

The polymerization temperature is 120 ° C. or higher, preferably 13
It is performed at 0 ° C or higher and 160 ° C or lower. If it is lower than 120 ° C, the efficiency of grafting the monomer to the polyether is lowered. Further, at a temperature higher than 160 ° C, thermal decomposition of the polyether and the graft polymer may occur.

During the graft polymerization, it is preferable that the polyether compound (A) is initially charged in a part or the whole amount. When maleic acid, fumaric acid or maleic anhydride is used as the monomer (b2), it is preferable to initially charge half or more of the amount of the monomer (b2) used together with the polyether compound (A). . Then, the remaining monomer and the initiator are separately added after heating the polyether at 120 ° C. or higher. At this time, when a part of the polyether compound (A) is initially charged, the remaining polyether compound (A) may be mixed with an initiator or a monomer and added dropwise.

The obtained polymer can be used as a dispersant or scale inhibitor by dissolving it in a solvent such as water or alcohol as it is, or by adding a base. Examples of the base include monovalent metal salts such as sodium salts and potassium salts, divalent metal salts such as calcium salts, trivalent metal salts such as aluminum salts, ammonium salts, organic amine salts such as monoethanolamine and triethanolamine. Can be mentioned. In that case, water is preferable as the solvent.

Since the water-soluble graft copolymer of the present invention has good gel resistance and optimum calcium ion trapping ability, it exhibits very good detergency when incorporated as a detergent composition. The content of the water-soluble graft copolymer in the detergent composition of the present invention is preferably in the range of 0.1 to 15% by weight for good detergency, more preferably 0.3 to 10% by weight, and more preferably 0.5. ~ 5 wt% is most preferred. The detergent composition containing the water-soluble graft copolymer of the present invention can also be used by incorporating a surfactant and, if necessary, an enzyme.

As the surface active agent, anionic surface active agents, nonionic surface active agents, amphoteric surface active agents and cationic surface active agents can be preferably used.

Examples of anionic surfactants include alkylbenzene sulfonates, alkyl or alkenyl ether sulfates, alkyl or alkenyl sulfates,
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 alkyl or alkenyl phosphate esters or salts thereof.

Examples of nonionic surfactants include polyoxyalkylene alkyl or alkenyl ethers, polyoxyethylene alkylphenyl ethers, higher fatty acid alkanolamides or their alkylene oxide adducts, sucrose fatty acid esters, alkylglycoxides, and fatty acid glycerin mono. Examples thereof include esters and alkylamine oxides.

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

The amount of these surfactants blended is 5 to 70.
It is preferable to blend the composition in an amount of 20% by weight, more preferably 20 to 60% by weight. However, when a nonionic surfactant is blended, 50% by weight or more of the nonionic surfactant,
The amount is preferably 60% by weight or more, and most preferably 70% by weight or more for the purpose of improving the detergency and simplifying the weighing operation when used as an industrial detergent.

As the enzyme to be incorporated in the detergent composition containing the water-soluble graft polymer of the present invention, protease, lipase, cellulase and the like can be used. In particular, protease, alkaline lipase, alkaline cellulase and the like, which have high activity in the alkaline washing solution, are preferable. The blending amount of the enzyme is preferably 0.01 to 5% by weight. If the amount is out of this range, the balance with the surfactant is lost and the detergency cannot be improved.

In the detergent composition containing the water-soluble graft polymer of the present invention, if necessary, a known alkali builder,
Ingredients commonly used in detergent compositions such as chelate builders, anti-redeposition agents, fluorescent agents, bleaching agents and fragrances may be added.
Moreover, you may mix | blend a zeolite. As the alkali builder, silicate, carbonate, sulfate and the like can be used. As the chelate builder, diglycolic acid, oxycarboxylic acid salt, EDTA (ethylenediaminetetraacetic acid), DTPA (diethylenetriaminehexaacetic acid) or the like can be used.

The water-soluble graft polymer of the present invention exhibits good performance as a dispersant for inorganic or organic substances which are poorly soluble in water. For example, it exhibits good performance as a dispersant for inorganic pigments such as heavy or light calcium carbonate and clay used for paper coating, and a dispersant for water slurry such as cement and coal. In addition, cooling water system, boiler water system, seawater desalination equipment, pulp digester, water treatment agent for scale prevention of calcium carbonate, silica, zinc, etc. in black liquor concentrator, dyeing aid and antistatic aid for fiber, etc. It can also be used as a fiber treatment agent.

Further, the water-soluble graft polymer of the present invention can be used as a water absorbent resin by crosslinking with a crosslinking agent. Since the water-soluble graft polymer obtained by the production method of the present invention has a high graft ratio, the water-absorbent resin obtained by cross-linking with a cross-linking agent has a small amount of soluble components, and since the main chain contains a polyether, it has salt resistance. A highly water-absorbent resin can be obtained. The crosslinking is carried out by a known method and is not particularly limited, but it is preferably carried out by reacting the carboxylic acid of the graft polymer with the crosslinking agent.

[0040]

【Example】

Example 1 A glass reactor equipped with a thermometer, a stirrer, a nitrogen inlet tube, and a reflux condenser was charged with 200 parts by weight of polyethylene glycol having an average molecular weight of 1000 and 22 parts by weight of maleic acid, and heated under a nitrogen stream. It was made to melt | dissolve, and it heated up to 145 degreeC under stirring. Next, the temperature is set to 145 to 147.
While maintaining the temperature at 50 ° C., 50 parts by weight of acrylic acid and 2.5 parts by weight of di-t-butylperoxide were separately added dropwise continuously over 1 hour, and then stirring was continued for 20 minutes. After cooling, added aqueous sodium hydroxide solution (10% solution) in a completely neutralized amount of acrylic acid and maleic acid, and heated at reflux temperature for 1 hour with stirring to obtain an aqueous sodium salt solution of graft polymer 1. .

(Measurement of Calcium Ion-Capturing Ability) To the calcium carbonate aqueous solution prepared under the following conditions, the sodium salt aqueous solution of the graft polymer 1 was added and stirred under the following conditions. The calcium ion concentration of the polymer was measured by an Orion calcium electrode (93-20) using an Orion ion analyzer (EA920), and the amount of calcium ions captured by the polymer was calculated as the number of mg in terms of calcium carbonate from the concentration difference before and after stirring. And the value was defined as the calcium ion-capturing ability of this polymer. The results are shown in Table 1.

Calcium ion trapping ability measuring conditions : Container: 100 cc beaker liquid: Ca ²⁺ 1.0 × 10 ⁻³ mol / L aqueous solution 50 cc Polymer: 10 mg (solid content conversion, graft polymer 1
Sodium salt) Temperature: 25 ° C. Stirring time: 10 minutes (using a stirrer) (Measurement of gelation resistance) CaC prepared under the following conditions
l ₂ , the sodium nitrate aqueous solution of the graft polymer 1 was added to the zinc nitrate test solution under the following conditions to cause gelation, and then the absorbance of the test solution was measured.
The gelation resistance of this polymer was used. The smaller the value, the higher the gelation resistance and the better the graft polymer.

Conditions for measuring gelation resistance : 1. Zinc nitrate hexahydrate 10 g, calcium chloride dihydrate 10
g, 10 g of a sodium salt aqueous solution of a graft polymer having a concentration of 25% by weight, and 10 g of ion-exchanged water were added to give a total of 40 g.
A test solution of g was prepared.

2. The test solution was sealed and allowed to stand in a constant temperature bath at 80 ° C for 30 minutes, and then UV wavelength of 380n was measured with a Shimadzu spectrophotometric cell.
Absorbance was measured at m.

3. The obtained numerical value was defined as gelation resistance. That is, the smaller this value, the better the gelation resistance. The results are shown in Table 1.

(Example 2) In a reactor similar to that of Example 1,
Charge 400 parts by weight of monomethoxypolyethylene glycol having an average molecular weight of 1000 and 22 parts by weight of maleic acid,
It was heated and melted under a nitrogen stream, and the temperature was raised to 130 ° C. under stirring. Next, while maintaining the temperature at 130 to 132 ° C., 53 parts by weight of acrylic acid and 5 parts by weight of di-t-butylperoxide were separately and continuously added dropwise over 1 hour, and then stirring was continued for 80 minutes. After cooling, an aqueous solution of sodium hydroxide (10% solution) in the completely neutralized amount of acrylic acid and maleic acid was added, and the mixture was heated at reflux temperature for 1 hour with stirring to obtain an aqueous sodium salt solution of graft polymer 2. . The same analysis as in Example 1 was performed, and the results are shown in Table 1.

(Example 3) In a reactor similar to that of Example 1,
200 parts by weight of polyethylene glycol having an average molecular weight of 500 and 20 parts by weight of maleic acid were charged, heated under a nitrogen stream to melt, and heated to 145 ° C. under stirring. Next, while maintaining the temperature at 146 to 147 ° C., 20 parts by weight of acrylic acid and 5 parts by weight of di-t-butylperoxide were separately added dropwise continuously over 1 hour, and then stirring was continued for 1 hour. After cooling, an aqueous solution of sodium hydroxide (10% solution) in a completely neutralized amount of acrylic acid added dropwise was added,
The mixture was heated at reflux temperature for 1 hour with stirring to obtain a sodium salt aqueous solution of the graft polymer 3. The same analysis as in Example 1 was performed, and the results are shown in Table 1.

(Example 4) In a reactor similar to that of Example 1,
200 parts by weight of polyethylene glycol having an average molecular weight of 500 and 20 parts by weight of maleic acid were charged, heated and melted under a nitrogen stream, and heated to 150 ° C. under stirring. Next, while maintaining the temperature at 150 to 152 ° C., 30 parts by weight of methacrylic acid and 3 parts by weight of di-t-butylperoxide were separately and continuously added dropwise over 1 hour, and then 3
Stirring was continued for 0 minutes. After cooling, a sodium hydroxide aqueous solution (10% solution) in a completely neutralized amount of methacrylic acid was added dropwise, and the mixture was heated at reflux temperature with stirring for 1 hour to obtain an aqueous sodium salt solution of the graft polymer 4. The same analysis as in Example 1 was performed, and the results are shown in Table 1.

(Example 5) In a reactor similar to that of Example 1,
100 parts by weight of monomethoxypolyethylene glycol having an average molecular weight of 700 and 15 parts by weight of maleic acid were charged, heated and melt-mixed under a nitrogen stream, and heated to 145 ° C. under stirring. Next, while maintaining the temperature at 145 to 147 ° C., 15 parts by weight of acrylic acid and 3 parts by weight of di-t-butylperoxide were separately added dropwise over 1 hour, and then stirring was continued for 1 hour.

After cooling, aqueous sodium hydroxide solution (10%
(Solution) was added with stirring to an amount of about 11 and heated at reflux temperature for 1 hour to obtain an aqueous sodium salt solution of the graft polymer 5. The same analysis as in Example 1 was performed, and the results are shown in Table 1.

Comparative Example 1 An aqueous sodium salt solution of Comparative Graft Polymer 1 was prepared in the same manner as in Example 1, except that the amount of acrylic acid used was 100 parts by weight instead of 50 parts by weight. Got The same analysis as in Example 1 was performed, and the results are shown in Table 2.

Comparative Example 2 An aqueous sodium salt solution of Comparative Graft Polymer 2 was obtained in the same manner as in Example 1 except that the amount of acrylic acid used was 3 parts by weight. The same analysis as in Example 1 was performed, and the results are shown in Table 2.

Comparative Example 3 An aqueous sodium salt solution of Comparative Graft Polymer 3 was obtained in the same manner as in Example 2 except that maleic acid was not used. The same analysis as in Example 1 was performed, and the results are shown in Table 2.

Comparative Example 4 A comparative graft polymer was prepared in the same manner as in Example 1 except that polyethylene glycol having an average molecular weight of 3000 was used in place of 200 parts by weight of polyethylene glycol having an average molecular weight of 1000. An aqueous sodium salt solution of No. 4 was obtained. The same analysis as in Example 1 was performed, and the results are shown in Table 2.

(Example 6) Graft polymer (1)-
In order to evaluate the performance of the detergent composition of (5), the following detergency test was conducted, and the results are shown in Table 6.

(Test method) 1. An artificial dirt solution was prepared by dispersing the artificial dirt of the components shown in Table 3 in carbon tetrachloride, and a white cotton cloth was passed through the artificial dirt solution, dried, and cut to obtain 10 cm × 1
A 0 cm soiled cloth was made.

2. The detergent composition shown in Table 4 was used to wash the contaminated cloth under the washing conditions shown in Table 5, the contaminated cloth was dried, and then the reflectance was measured.

3. The cleaning rate was calculated from the following formula.

Washing rate = (reflectance after washing−reflectance before washing) / (reflectance of white cloth−reflectance before washing) × 100 (Comparative Example 5) Comparative graft polymers (1) to (4) Was evaluated in the same manner as in Example 6 and the results are shown in Table 7.

Example 7 Graft polymer (1)-
In order to evaluate the performance of the detergent composition of (5), the following detergency test was conducted, and the results are shown in Table 11.

(Test method) 1. The artificial dirt of the components shown in Table 8 was dispersed in carbon tetrachloride to prepare an artificial dirt solution, and a white cotton cloth was passed through the artificial dirt solution, dried, and cut to obtain 10 cm × 1
A 0 cm soiled cloth was made.

2. Using the detergent composition shown in Table 9, the contaminated cloth was washed under the washing conditions shown in Table 10, the contaminated cloth was dried, and then the reflectance was measured.

3. The cleaning rate was calculated from the following formula.

Washing rate = (reflectance after washing−reflectance before washing) / (reflectance of white cloth−reflectance before washing) × 100 (Comparative Example 6) Comparative graft polymers (1) to (4) Was evaluated in the same manner as in Example 7, and the results are shown in Table 12.

[0065]

[Table 1]

[0066]

[Table 2]

[0067]

[Table 3]

[0068]

[Table 4]

[0069]

[Table 5]

[0070]

[Table 6]

[0071]

[Table 7]

[0072]

[Table 8]

[0073]

[Table 9]

[0074]

[Table 10]

[0075]

[Table 11]

[0076]

[Table 12]

Claims (6)

[Claims] 1. A (poly) ether compound is grafted with (meth) acrylic acid and an ethylenically unsaturated dicarboxylic acid type monomer, and has a calcium ion trapping ability of 40 to 130.
A water-soluble graft polymer having mgCaCO ₃ / g and a gelation resistance of 1.5 or less. 2. A number average molecular weight of 250 or more and 1900 having ethylene oxide as a constituent unit of 80 mol% or more.
To the following polyether compound (A), a monomer component (B) consisting of 50 to 80 mol% of (meth) acrylic acid (b1) and 20 to 50 mol% of an ethylenically unsaturated dicarboxylic acid type monomer (b2) is added. A method for producing a water-soluble graft polymer, which comprises graft-polymerizing the polyether compound (A) in an amount of 25-40 wt%. 3. At least one selected from the group consisting of maleic acid, fumaric acid and maleic anhydride as the monomer component (b2).
One monomer is used, and more than half of the amount of the monomer component (b2) used is mixed in advance with the polyether compound, and then the rest of the monomer component (B) and the polymerization initiator are added. The method for producing a water-soluble graft polymer according to claim 1, wherein the graft polymerization is carried out at a temperature of 120 ° C. or higher without using a solvent. 4. The water-soluble graft polymer according to claim 1,
And a detergent composition comprising a surfactant. 5. The water-soluble graft polymer according to claim 1, in an amount of 0.1 to 15% by weight, and a nonionic surfactant 50.
A detergent composition containing at least wt%. 6. The detergent composition according to claim 5, wherein the nonionic surfactant is an alkoxylate of a linear secondary alcohol.