WO2006112492A2

WO2006112492A2 - Additives for high-concentration anionic surfactants

Info

Publication number: WO2006112492A2
Application number: PCT/JP2006/308259
Authority: WO
Inventors: Kazuhiro Iitaka; Takeshi Tomifuji; Tomokatsu Kusumi; Yoshinori Mitsuda; Jun Kono
Original assignee: Kao Corporation
Priority date: 2005-04-14
Filing date: 2006-04-13
Publication date: 2006-10-26
Also published as: KR101290387B1; KR20070121736A; WO2006112492A3; CN101160383B; CN101160383A

Abstract

Additives for high-concentration anionic surfactants including at least one nitrogen-containing compound selected from amidoalcohol compounds, amidoamine compounds, betaine-type compounds, and imidazoline-type compounds, and anionic surfactant compositions containing the additive for high-concentration anionic surfactants.

Description

ADDITIVES FOR HIGH-CONCENTRATIONANIONIC SURFACTANTS

FIELD OF THE INVENTION

The present invention relates to additives for high-concentration anionic surfactants and anionic surfactant compositions containing the additive.

BACKGROUND OF THE INVENTION

Alkyl ether sulfates obtainable by the sulfation of alkylene oxide adducts (oxyalkylene alkyl ether) of higher alcohols are less irritant to human skins, and therefore, widely used as liquid detergents such as shampoos, medicines and anionic surfactants for cosmetics.

Generally, alkyl ether sulfates are produced in the form of pasty compositions or liquid compositions each containing water. In view of handling ability, efficiency of production apparatus, shipping costs and flowability, it is preferred to make the concentration of effective ingredients in the compositions as high as possible. The flowability of alkyl ether sulfate compositions varies depending upon the chemical structure of the starting higher alcohol, the number of oxyalkylene repeating units, the amount of oxyalkylene alkyl ether remaining non-reacted and the contents of by produced alkylene ether glycol and inorganic salts. Therefore, the flowability is quite different from composition to composition even when the concentration of effective ingredients is the same. For example, it has been known that the flowability is lowered in some cases to a degree which makes it difficult to draw the alkyl ether sulfate composition out of a drum container. Therefore, it would be industrially extremely advantageous if the flowability of compositions containing the alkyl ether sulfate in higher concentrations can be made higher without reducing the concentration of the alkyl ether sulfate, because the production efficiency is improved and the shipping costs can be reduced. To improve the flowability of alkyl ether sulfate compositions, there has been proposed, for example, (l) a composition containing an alkyl ether sulfate and a salt of alkylene ether glycol sulfate serving as a viscosity modifier, which is produced from a polyalkylene ether glycol (for example, JP 56-36596A), and (2) a low viscosity surfactant which is produced by adding a polyethylene glycol having an average molecular weight of 300 to 6000 to an oxyalkylene alkyl ether sulfate in a proportion of 0.1 to 25% by mass of the sulfate during or after the neutralization of the sulfate (for example, JP 50-116383A).

Although the composition 1 and the low viscosity surfactant 2 improve the flowability to some extent, the improvement is still insufficient. Therefore, there has been a demand for developing an alkyl ether sulfate composition exhibiting higher flowability and a flowability improver which is capable of providing such an alkyl ether sulfate composition.

SUMMARY OF THE INVENTION The present invention provides novel additives useful as the flowability improver for high-concentration anionic surfactants such as alkyl sulfate compositions and alkyl ether sulfate compositions and also provides high- concentration anionic surfactant compositions containing such additives. The inventors have found that nitrogen-containing compounds, particularly, an amidoalcohol compound, an amidoamine compound, a betaine- type compound, and an imidazoline -type compound exhibit excellent effects in improving the flowability of alkyl sulfate compositions and alkyl ether sulfate compositions.

Thus, the present invention provides^ (l) an additive for high-concentration anionic surfactants containing a nitrogen-containing compound, wherein the nitrogen-containing compound is at least one compound selected from: amidoalcohol compounds represented by the following Formula l:

wherein R¹ is a straight- or branched-chain, unsubstituted or hydroxy substituted alkyl group or alkenyl group each having from 5 to 23 carbon atoms, R² is hydrogen atom or a straight- or branched-chain alkyl group having from 1 to 3 carbon atoms, and R³ is a straight- or branched-chain alkylene group having from 1 to 6 carbon atoms or a straight- or branched- chain alkenylene group having from 2 to 6 carbon atoms?" amidoamine compounds represented by the following Formula 2-

wherein R⁴ is a straight- or branched-chain alkyl group or alkenyl group each having from 7 to 19 carbon atoms, R⁵ is -CH₂COOM, -CH₂CH₂COOM or -CH₂CH(OH)CH₂SOaM wherein M is hydrogen atom, an alkali metal, an alkaline earth metal, ammonium or an alkanol amine, R⁶ and R⁷ are each independently a straight- or branched-chain alkylene group having from 2 to 6 carbon atoms! amidoamine compounds represented by the following Formula 3:

wherein R⁸ is a straight- or branched-chain alkyl group or alkenyl group each having from 7 to 19 carbon atoms, R⁹ is -CH₂COOM, -CH₂CH₂COOM or -CH₂CH(OH)CH₂SO₃M wherein M is hydrogen atom, an alkali metal, an alkaline earth metal, ammonium or an alkanol amine, R¹⁰ is hydrogen atom, -CH₂COOM, -CH₂CH₂COOM or -CH₂CH(OH)CH₂SO₃M wherein M is the same as defined above, R¹¹ is hydrogen atom or a straight- or branched-chain alkyl group or hydroxyalkyl group each having from 1 to 6 carbon atoms, and R¹² is a straight- or branched-chain alkylene group having from 2 to 6 carbon atoms; betaine-type compounds represented by the following Formula 4^:

wherein R¹³ is a straight- or branched-chain alkyl group or alkenyl group each having from 8 to 18 carbon atoms or R¹⁴CONH(CH2)_a- wherein R¹⁴CO is an acyl group having from 8 to 18 carbon atoms and a subscript a is an integer from 2 to 4, and X^~ is -CH₂CH(OH)CH₂SO₃ ^" or -CH₂COO-; and imidazoline-type compounds represented by the following Formula 5^:

wherein R¹⁶ is a straight- or branched-chain alkyl group or alkenyl group each having from 8 to 18 carbon atoms, and further provides

(2) an anionic surfactant composition containing the additive for high- concentration anionic surfactants mentioned above, a compound represented by the following Formula 6:

RO(AO)₁₁₁SO₃M¹ (6) wherein R is a straight- or branched-chain alkyl group or alkenyl group each having from 9 to 24 carbon atoms, A is an alkylene group having from 2 to 4 carbon atoms, M¹ is hydrogen atom, an alkali metal or NH₄, and a subscript m is an average number from O to 4, and water.

DETAILED DESCRIPTION OF THE INVENTION

The additive for high-concentration anionic surfactants of the present invention includes at least one nitrogen-containing compound. To effectively improve the flowability of alkyl sulfate (AS) compositions and alkyl ether sulfate (ES) compositions, the amidoalcohol compounds, the amidoamine compounds, the betaine-type compounds, and the imidazoline -type compounds described below are suitable as the nitrogen-containing compound.

The amidoalcohol compounds include the compounds represented by the following Formula 1-

In Formula 1, R¹ is a straight- or branched-chain alkyl group or alkenyl group each having from 5 to 23 carbon atoms, preferably from 7 to 19 carbon atoms, which may have a hydroxyl group. Examples of the acyl group represented by R¹CO- include acyl groups derived from octanoic acid, decanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid, octadecanoic acid, docosanoic acid, linoleic acid, 2-ethylhexanoic acid, 2-octylundecanoic acid, isostearic acid, oleic acid, coconut fatty acids, palm fatty acids, palm kernel fatty acids, tallow fatty acids, etc., with acyl groups derived from octanoic acid, decanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid, octadecanoic acid, oleic acid, coconut fatty acid, palm fatty acid, palm kernel fatty acid, and tallow fatty acids being particularly preferred. The amidoalcohol compound may be a single compound or a mixture of compounds each represented by Formula 1. It is preferred that 50% by mass or more of the acyl groups in the amidoalcohol compound is derived from a fatty acid having from 12 to 14 carbon atoms, and more preferred that 40% by mass or more but less than 100% by mass of the acyl groups is derived from a fatty acid having 12 carbon atoms.

R² of Formula 1 is hydrogen atom or a straight- or branched-chain alkyl group having from 1 to 3 carbon atoms, preferably methyl group or ethyl group, and more preferably methyl group. R³ is a straight- or branched-chain alkylene group having from 1 to 6 carbon atoms or a straight- or branched- chain alkenylene group having from 2 to 6 carbon atoms, and preferably a straight- or branched-chain alkylene group having from 2 or 3 carbon atoms.

Examples of the amidoalcohol compounds of Formula 1 include N- ethanol-N-methyloctanamide, N-ethanol-N-methyldecanamide, N-ethanol-N- methyldodecanamide, N-ethanol-N-methyltetradecanamide, N-ethanol-N- methylhexadecanamide, N-ethanol-N-methyloctadecanamide, N-ethanol-N- methyl coconut fatty acid amide, N-ethanol-N-methyl palm kernel fatty acid amide, N-isopropanol-N-ethyldodecanamide, N-ethyl-N-isopropanololeamide, and N-ethyl-N-isopropanolisostearamide.

The amidoalcohol compound of Formula 1 is obtainable by any known method without specific limitation, for example, by purifying the reaction product by steam distillation after the dehydration reaction of a fatty acid and an alkanol amine, the reaction of a fatty acid halide and an alkanol amine, or the ester-amide exchange reaction of a fat or an ester of fatty acid with a lower alcohol with an alkanol amine in the presence of an alkali catalyst. The amidoalcohol compound obtainable by the above methods may contain slight amounts of alkanol amine, fatty acid, inorganic salt, glycerol, etc. in some cases. However, the amounts of these compounds are such that the performance of the additive for high-concentration anionic surfactants is not adversely affected.

The amidoamine compounds include the compounds represented by the following Formula %

In Formula 2, R⁴ is a straight- or branched-chain alkjd group or alkeiryl group each having from 7 to 19 carbon atoms, preferably an alkyl group having from 11 to 15 carbon atoms. The acyl group represented by R⁴CO- is preferably lauroyl group, myristoyl group, palmitoyl group, or cocoyl group. . R5 is -CH₂COOM, -CH2CH2COOM or -CH₂CH(OH)CH₂SO₃M. M is hydrogen atom, an alkali metal such as sodium and potassium, an alkaline earth metal such as calcium and magnesium, ammonium or an alkanolamine such as triethanolamine, with the alkali metal and alkanolamine being particularly preferred.

The amidoamine compound may be a single compound or a mixture of compounds each represented by Formula 2. It is preferred that 50% by mass or more of the acyl groups in the amidoamine compound is derived from a fatty acid having from 12 to 14 carbon atoms, and more preferred that 40% by mass or more but less than 100% by mass of the acyl groups is derived from a fatty acid having 12 carbon atoms.

R⁶ and R⁷ are each independently a straight- or branched-chain alkylene group having from 2 to 6 carbon atoms, preferably ethylene group.

Examples of the compounds represented by Formula 2 include N- lauroyl-N'-carboxymethyl-N'-(2-hydroxyethyl)ethylenediamine, N-lauroyl-N'- carboxyethyl-N'-(2-hydroxyethyl)ethyleiiediamine, N-myristoyl-N'- carboxymethyl-N'-(2-hydroxyethyl)ethylenediamine, N-myristoyl-N'- carboxyethyl-N'-(2-hydroxyethyl)ethylenediamine, N-cocoyl-N'-carboxymethyl- N'-(2-hydroxyethyl)ethylenediamine, N-cocoyl-N'-carboxyethyl-N'-(2- hydroxyethyl)ethylenedianiine, N-palmitoyl-N'-carboxymethyl-N'-(2- hydroxye thy 1) ethylene diamine , N-p almitoyl- N' - carboxy ethyl - N' - (2 ^■ hydroxyethyDethylenediamine, and salts of the preceding compounds. Other types of amidoamine compounds include the compounds represented by the following Formula 3-

In Formula 3, R⁸ is a straight- or branched-chain alkyl group or alkenyl group each having from 7 to 19 carbon atoms, preferably an alkyl group having from 11 to 15 carbon atoms. The acyl group represented by R⁸CO- is preferably lauroyl group, myristoyl group, palmitoyl group, or cocoyl group.

The amidoamine compound may be a single compound or a mixture of compounds each represented by Formula 3. It is preferred that 50% by mass or more of the acyl groups in the amidoamine compound is derived from a fatty acid having from 12 to 14 carbon atoms, and more preferred that 40% by mass or more but less than 100% by mass of the acyl groups is derived from a fatty acid having 12 carbon atoms.

R9 is -CH₂COOM, -CH₂CH₂COOM or -CH₂CH(OH)CH₂SO₃M, and R¹⁰ is hydrogen atom, -CH₂COOM, -CH₂CH₂COOM or -CH₂CH(OH)CH₂SO₃M. M is hydrogen atom, an alkali metal such as sodium and potassium, an alkaline earth metal such as calcium and, magnesium, ammonium or an alkanolamine such as ethanolamine, with the alkali metal and alkanolamine being particularly preferred. R¹¹ is a straight- or branched chain alkyl group or hydroxyalkyl group each having from 1 to 6 carbon atoms, and R¹² is a straight- or branched-chain alkylene group having from 2 to 6 carbon atoms, preferably ethylene group.

Examples of the compounds of Formula 3 include N-lauroyl-N-(2- hydroxyethyl)-N'-carboxymethylethylenediamine, N-lauroyl-N-(2- hydroxyethyl)-N',N'-bis(carboxymethyl)ethylenediamine, N-lauroyl-N-(2- hydroxyethyl)-N',N'-bis(carboxyethyl)ethylenediamine, N-myristoyl-N-(2- hydroxyethyl)-N'-carboxymethylethylenediamine, N-myristoyl-N-(2- hydroxyethyl)"N',N'-bis(carboxymethyl)ethylenediamine, N-myristoyl-N-(2- hydroxyethyl)-N',N'-bis(carboxyethyl)ethylenediamine, N-cocoyl-N-(2- hydroxyethyl)-N'-carboxymethylethylenediamine, N-cocoyl-N-(2-hydroxyethyl)- N',N'-bis(carboxymethyl)ethylenediamine, N-cocoyl-N-(2-hydroxyethyl)-N',N'- bis(carhoxyeth3d)ethylenediamine, N-palmitoyl-N-(2-hydroxyethyl)-N'- carboxymethylethylenediamine, N-palmitoyl-N-(2-hydroxyethyl)-N',N'- bis(carboxymethyl)ethylenediamine, N-palmitpyl-N-(2-hydroxyethyl)-N',N'- bis(carboxyethyl)ethylenediamine, and slats of the preceding compounds. The amidoamine compounds of Formulae 2 and 3 are obtainable, for example, by reacting one mole of imidazoline derivative with 1 to 2 mol of monochloroacetic acid, acrylic acid, etc.

The betaine-type compounds include the compounds represented by the following Formula 4-

In Formula 4, R¹³ is a straight- or branched-chain alkyl group or alkenyl group each having from 8 to 18, preferably from 10 to 14 carbon atoms, or R^l4CONH(CH₂)_a- wherein R¹⁴CO is an acyl group having from 8 to 18, preferably from 10 to 14 carbon atoms and the subscribe a is an integer from 2 to 4, preferably 3. Alternatively, R¹³ and R¹⁴CO may be respectively a mixed alkyl group or alkenyl group or a mixed acyl group which are derived from animal natural oils such as tallow oil and lard oil, vegetable natural oils such as soybean oil, coconut oil and palm kernel oil, synthetic oils or mixtures thereof, with a mixed alkyl group or a mixed acyl group derived from coconut oil or palm kernel oil being particularly preferred.

The betaine-type compound may be a single compound or a mixture of compounds each represented by Formula 4. It is preferred that 50% by mass or more of the acyl groups in the betaine-type compound is derived from a fatty acid having from 12 to 14 carbon atoms, and more preferred that 40% by mass or more but less than 100% by mass of the acyl groups is derived from a fatty acid having 12 carbon atoms.

X- is -CH₂CH(OH)CH₂SO₃ ^" or -CH₂COO-.

The betaine-type compound of Formula 4 is preferably a hydroxy sulfobetaine in which R¹³ is an alkyl group or alkenyl group each having from 8 to 18 carbon atoms and X^" is -CH₂CH(OH)CH₂SOs-, or an amidopropyl carboxybetaine in which R¹³ is R¹⁴CONHCSHG- wherein R¹⁴CO is the same as defined above and X^~ is -CH2COO^".

Specific examples of the betaine-type compounds of Formula 4 include lauryldimethylhydroxy sulfobetaine of Formula 4Λ-

lauroylaminopropyldimethyl carboxybetaine of Formula 4-2:

cocoamidopropyldimethyl carboxybetaine of Formula 4-3:

(R¹ CO: derived from coconut fatty acid)

The imidazoline -type compounds include the compounds represented by the following Formula 5:

In Formula 5, R¹⁶ is a straight- or branched-chain alkyl group or alkenyl group each having from 8 to 18, preferably from 10 to 14 carbon atoms, or a mixed alkyl group or alkenyl group derived from animal natural oils such as tallow oil and lard oil, vegetable natural oils such as soybean oil, coconut oil and palm kernel oil, synthetic oils or mixtures thereof.

The additive for high-concentration anionic surfactants of the invention contains at least one nitrogen -containing compound selected from the compounds of Formulae 1 to 5. If contains two or more, the nitrogen- containing compounds may be mixed in any ratio, because the mixing ratio affects nothing on the performance of the additive for high-concentration anionic surfactants. The term "high-concentration" referred to herein means that the anionic surfactant is contained in a great quantity, preferably 40% by mass or more, more preferably 50% by mass or more in a mixture containing water. Although not specifically limited, the upper limit of the content of anionic surfactant is preferably 90% by mass, and more preferably 75% by mass based on the mixture containing water.

The anionic surfactant composition of the invention contains the additive for high-concentration anionic surfactants including at least one nitrogen-containing compound represented by Formulae 1 to 5, at least one compound such as alkyl sulfate (AS) and alkyl ether sulfate (ES) represented by the following Formula 6:

and water.

In Formula 6, R is a straight- or branched-chain alkyl group or alkenyl group each having from 9 to 24, preferably from 12 to 20 carbon atoms. If the carbon number of R is within the range of from 9 to 24, the resultant compound of Formula 6 is well-balanced in the surface activity and the solubility in water. The alkyl group and alkenyl group may be either straight- or branched-chain, and examples thereof include decyl group, dodecyl group, tetradecyl group, hexadecyl group, octadecyl group, icosyl group, docosyl group, and oleyl group, each including isomers.

A is an alkylene group having from 2 to 4 carbon atoms, which may be either a straight- or branched-chain. Examples thereof include ethylene group, propylene group, 1-methyltrimethylene group, trimethylene group, and tetraniethylene group, with ethylene group or propylene group being preferred and ethylene group being more preferred. M¹ is hydrogen atom, an alkali metal or NH₄. The alkali metal may include sodium, potassium and lithium, with sodium or potassium being preferred and sodium being more preferred.

The subscript m is an average number from 0 to 4, preferably from 0.1 to 2, more preferably from 0.5 to 1.5.

The content of the additive for high-concentration anionic surfactants in the anionic surfactant composition is preferably from 0.1 to 50 parts by mass, more preferably from 1 to 30 parts by mass, and still more preferably from 2 to 20 parts by mass, each based on 100 parts by mass of the compound of Formula 6, although varies depending upon the kinds of the compound of

Formula 6 and additive for high-concentration anionic surfactants. By adding the additive for high-concentration anionic surfactants of the invention to the compound of Formula 6 in such a proportion, the resultant composition exhibits a good flowability and handling ability even when contains the compound of Formula 6 at high concentrations. The content of water is preferably from 10 to 60 parts by mass, more preferably from 20 to 50 parts by mass, and still more preferably from 25 to 40 parts by mass, each base on 100 parts by mass of the compound of Formula 6.

The anionic surfactant composition of the invention essentially contains three components : the anionic surfactant represented by Formula 6 as the major component, the nitrogen-containing compound represented by Formulae 1 to 5, and water. Since a good flowability is attained without needing another flowability aid such as inorganic salt, the composition of the invention is utilized as an intermediate product for detergents, etc., for example, as an anionic surfactant premix.

As noted above, the advantage of the composition lies in the excellent flowability which enhances the handling ability thereof. Therefore, the composition is suitably used as a premix applicable to raw materials for shampoo, liquid body soap, etc. Generally, an inorganic salt is added to a surfactant composition as a viscosity modifier in some cases. However, the addition of the inorganic salt necessitates an additional operation of re -controlling the viscosity of final products such as shampoo. In contrast, the anionic surfactant composition of the invention is a premix containing, as the basic effective ingredients, the anionic surfactant (compound of Formula 6) and the auxiliary surfactant (nitrogen-containing compound of Formulae 1 to 5), and the inorganic salt is not necessarily required to be contained in the premix. Therefore, the operation of re -controlling the viscosity of final products such as shampoo or others can be omitted. To stabilize the anionic surfactant premix of the invention, the pH thereof is preferably around neutrality, more preferably from 5 to 8, and still more preferably from 5.5 to 7.5. To regulate the pH within the above range, it is recommended to add a pH buffer such as phosphoric acid, citric acid, poly basic acids or any other acids to the premix. The anionic surfactant composition of the invention is obtainable by a known method and adequately used for manufacturing liquid detergent compositions. The liquid detergent compositions may contain, if necessaiy, adjuvant such as colorants, fragrances, solubilizers and builders. To regulate the cleaning power and lathering, other types of anionic surfactants, cationic surfactants, amphoteric surfactants and nonionic surfactants may be added. The liquid detergent compositions are used, for example, as shampoo, body shampoo, kitchen detergent and liquid soap. SYNTHETIC EXAMPLE 1 (Addition of alkylene oxide)

Into a C 12/14 higher alcohol placed in a pressure reactor, ethylene oxide was introduced in the presence of a catalyst in a manner ordinarily employed in the art, to obtain an ethylene oxide adduct of the higher alcohol (higher alcohol ethoxylate). The obtained ethylene oxide adduct was then sulfated in the manner described below. SYNTHETIC EXAMPLE 2 (Sulfation) Using a thin film continuous sulfation apparatus, a C12/14 higher alcohol ethoxylate (average addition of ethylene oxide: 1.0 mol) was sulfated with SO3 gas by a known method. The sulfated product was poured into a 26% by mass aqueous solution of sodium hydroxide for neutralization, to obtain an aqueous solution of anionic surfactant (water content: 28% by mass). EXAMPLES 1-7

Into the aqueous solution of anionic surfactant prepared in Synthetic Example, each additive shown in Table 1 was added. After optionally diluting with water or concentrating using a rotary evaporator if needed, the resultant mixture was cooled and subjected to defoaming treatment under reduced pressure, to obtain each anionic surfactant composition.

The flowability of each anionic surfactant composition was evaluated as follows. Into a cylindrical glass tube with an inner diameter of 10 mm that stood vertically, 15 mL of the sample composition was introduced. After sealing the upper end, the sample composition was left to stand at each temperature shown in Table 1 for a sufficient period of time. Thereafter, the upper end was opened to allow the sample composition to flow down, to measure the time taken until the lower end of the sample composition moved down by 10 cm as the index of the flowability.

The results are shown in Table 1 together with the content of the additive and the concentration of the anionic surfactant. COMPARATIVE EXAMPLES 1-4

The aqueous solution of anionic surfactant prepared in Synthetic Example was subjected to defoaming treatment under reduced pressure without adding the additive. Thereafter, the aqueous solution of anionic surfactant was evaluated for the flowability in the same manner as above.

The results are shown in Table 1 together with the concentration of the anionic surfactant. Table 1

Additive Anionic Surfactant

, . , content of effective ingredient concentration*

Examples

1 A-I 2 71

2 A-2 2 70-

3 A-3 2 69

4 A-4 2 72

5 A-5 2 71

6 A-I 10 65

7 A-I 10 65

Comparative Examples

1 — — 70

2 — — 70

3 — — 62

4 — — 62

*^'■ Concentration of sodium salt of higher alcohol ethoxylate sulfate

Table 1 (contd.)

Flowability Temperature for (s) leaving to stand pH** (⁰C)

Examples

1 200 20 6.7

2 134 20 6.7

3 116 20 6.7

4 323 20 6.7

5 161 20 6.7

6 296 20 6.7

7 327 10 6.7

Comparative Examples

1 not flow down 20 6.7

2 not flow down 10 6.7

3 not flow down 20 6.7

4 not flow down 10 6.7

**^'■ pH of a 10% aqueous solution of sodium salt of higher alcohol ethoxylate sulfate A-I: "Aminon C-IlS" manufactured by Kao Corporation

RCO- : derived from coconut fatty acid A-2: "Amphitol 55AB" manufactured by Kao Corporation

R CO— : derived from coconut fatty acid 5 A- 3: "Amphitol 20HD" manufactured by Kao Corporation

A-4: "Ainisol CME" manufactured by Kawaken Fine Chemicals Co., Ltd.

R CO— '■ derived from coconut fatty acid

A-5: "Amphitol 20YB" manufactured by Kao Corporation

-J_^Q R C^~: derived from coconut fatty acid

As described above, the additive for high-concentration anionic surfactants containing the nitrogen-containing compound of the invention is useful as the flowability improver for alkyl sulfate and/or alkyl ether sulfate compositions. Using the additive for high -concentration anionic surfactants,

15 anionic surfactant compositions exhibiting a good flowability can be obtained even when containing the alkyl sulfate and/or the alkyl ether sulfate at higher concentrations .

Claims

1. An additive for high-concentration anionic surfactants comprising a nitrogen-containing compound, wherein the nitrogen-containing compound is at least one compound selected from: amidoalcohol compounds represented by the following Formula l:

wherein R¹ is a straight- or branched-chain, unsubstituted or hydroxy- substituted alkyl group or alkenyl group each having from 5 to 23 carbon atoms, R² is hydrogen atom or a straight- or branched-chain alkyl group having from 1 to 3 carbon atoms, and R³ is a straight- or branched-chain alkylene group having from 1 to 6 carbon atoms or a straight- or branched- chain alkenylene group having from 2 to 6 carbon atoms,^' amidoamine compounds represented by the following Formula 2^'-

wherein R⁴ is a straight- or branched-chain alkyl group or alkenyl group each having from 7 to 19 carbon atoms, R⁵ is -CH₂COOM, -CH₂CH₂COOM or -CH₂CH(OH)CH₂SOSM wherein M is hydrogen atom, an alkali metal, an alkaline earth metal, ammonium or an alkanol amine, R⁶ and R⁷ are each independently a straight- or branched-chain alkylene group having from 2 to 6 carbon atoms; amidoamine compounds represented by the following Formula 3^

wherein R⁸ is a straight- or hranched-chain alkyl group or alkenyl group each having from 7 to 19 carbon atoms, R⁹ is -CH₂COOM, -CH₂CH₂COOM or -CH₂CH(OH)CH₂SOSM wherein M is hydrogen atom, an alkali metal, an alkaline earth metal, ammonium or an alkanol amine, R¹⁰ is hydrogen atom, -CH₂COOM, -CH₂CH₂COOM or -CH₂CH(OH)CH₂SO₃M wherein M is the same as defined above, R¹¹ is hydrogen atom or a straight- or branched-chain alkyl group or hydroxyalkyl group each having from 1 to 6 carbon atoms, and R¹² is a straight- or branched-chain alkylene group having from 2 to 6 carbon atoms; betaine-type compounds represented by the following Formula 4'-

wherein R¹³ is a straight- or branched-chain alkyl group or alkenyl group each having from 8 to 18 carbon atoms or R¹⁴CONH(CH₂)_a- wherein R¹⁴CO is an acyl group having from 8 to 18 carbon atoms and a subscript a is an integer from 2 to 4, and X^" is -CH₂CH(OH)CH₂SO₃ ^" or -CH₂COO^"; and imidazoline-type compounds represented by the following Formula 5^

wherein R¹⁶ is a straight- or branched-chain alkyl group or alkenyl group each having from 8 to 18 carbon atoms.

2. An anionic surfactant composition comprising the additive for high- concentration anionic surfactants as defined in claim 1, at least one compound represented by the following Formula 6:

RO(AO)_1nSO₃Mⁱ (6) wherein R is a straight- or branched-chain alkyl group or alkenyl group each having from 9 to 24 carbon atoms, A is an alkylene group having from 2 to 4 carbon atoms, M¹ is hydrogen atom, an alkali metal or NH4, and a subscript m is an average number from 0 to 4, and water.

3. The anionic surfactant composition according to claim 2, which comprises 100 parts by mass of the compound of Formula 6, from 0.1 to 50 parts by mass of the additive for high-concentration anionic surfactants, and from 10 to 60 parts by mass of water.

4. An anionic surfactant premix comprising at least one compound represented by Formula 6 as defined in claim 1 as a main ingredient and further comprising at least one nitrogen-containing compound represented by any of Formulae 1 to 5 as defined in claim 1 and water.

5. Use of a nitrogen-containing compound for enhancing fluidity of high- concentration anionic surfactants, wherein the nitrogen-containing compound is at least one compound selected from: amidoalcohol compounds represented by the following Formula l:

wherein R¹ is a straight- or branched-chain, unsubstituted or hydroxy- substituted alkyl group or alkenyl group each having from 5 to 23 carbon atoms, R² is hydrogen atom or a straight- or branched-chain alkyl group having from 1 to 3 carbon atoms, and R³ is a straight- or branched-chain alkylene group having from 1 to 6 carbon atoms or a straight- or branched- chain alkenylene group having from 2 to 6 carbon atoms; amidoamine compounds represented by the following Formula %

wherein R⁴ is a straight- or branched-chain alkyl group or alkenyl group each having from 7 to 19 carbon atoms, R⁵ is -CH₂COOM, -CH₂CH₂COOM or -CH₂CH(OH)CH₂SOSM wherein M is hydrogen atom, an alkali metal, an alkaline earth metal, ammonium or an alkanol amine, R⁶ and R⁷ are each independently a straight- or branched-chain alkylene group having from 2 to 6 carbon atoms; amidoamine compounds represented by the following Formula 3^:

wherein R⁸ is a straight- or branched-chain alkyl group or alkenyl group each having from 7 to 19 carbon atoms, R⁹ is -CH₂COOM, -CH₂CH₂COOM or -CH₂CH(OH)CH₂SOSM wherein M is hydrogen atom, an alkali metal, an alkaline earth metal, ammonium or an alkanol amine, R¹⁰ is hydrogen atom, -CH₂COOM, -CH₂CH₂COOM or -CH₂CH(OH)CH₂SO₃M wherein M is the same as defined above, R¹¹ is hydrogen atom or a straight- or branched-chain alkyl group or hydroxyalkyl group each having from 1 to 6 carbon atoms, and R¹² is a straight- or branched-chain alkylene group having from 2 to 6 carbon atoms; betaine-type compounds represented by the following Formula 4'-

wherein R¹³ is a straight- or branched-chain alkyl group or alkenyl group each having from 8 to 18 carbon atoms or R¹⁴CONH(CH₂)_a- wherein R¹⁴CO is an acyl group having from 8 to 18 carbon atoms and a subscript a is an integer from 2 to 4, and X^" is -CH₂CH(OH)CH₂SO₃- or -CH₂COO-; and imidazoline-type compounds represented by the following Formula 5'-