JP2698601B2 - Method for producing amphoteric surfactant composition - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a method for producing an amide amino acid type activator composition, and more particularly to salts of N-acyl-N'-hydroxyethyl-N'-carboxymethylethylenediamine. ,
And / or N-acyl-N- (2-hydroxyethyl)
The present invention relates to a process for producing a high-concentration amphoteric surfactant composition having improved flowability, comprising a salt of -N ', N'-bis (carboxymethyl) ethylenediamine and a specific polar solvent. .

[Problems to be solved by conventional technology and invention]

In recent years, surfactants used for detergents and the like have been demanded to have excellent properties such as biodegradability, safety, and low irritation to eyes and skin, in addition to surface activity. One of the surfactants satisfying these requirements is an imidazoline surfactant. The imidazoline surfactants are characterized by extremely low irritation to the eyes and skin in addition to excellent foaming and detergency, and their use as a major component of low-irritant shampoos has recently been increasing.

The imidazoline-based surfactant is produced by a method in which alkylimidazoline is reacted with monochloroacetic acid or an alkali metal salt thereof to amphoteric. The imidazoline-based surfactant obtained by this reaction has long been considered to have an imidazoline skeleton. However, recent studies have revealed that imidazoline is ring-opened, for example, as shown in Formula (1) or Formula (2). It is clear that the structure is the same.

Such surfactants are still referred to as imidazoline-based surfactants today, but are referred to herein as "amide amino acid type surfactants" from this structure.

Generally, the compound represented by the structure of the above (1) or (2) is used alone or in an aqueous solution of a mixture.
The concentration of the activator, the pH, the salt produced as a by-product, and the alkyl composition of the fatty acid or methyl ester used as the raw material greatly affect the viscosity of the solution. Of these, the pH is adjusted to near neutrality and the alkyl composition generally uses a coconut composition or lauryl group. The amount of by-produced salt varies depending on the amount of monochloroacetic acid or a salt thereof used, but in general, in order to increase the yield, use monochloroacetic acid or a salt thereof in an equimolar amount or more with respect to the raw material amine, and As a result, 1 mol or more of salt is by-produced. Therefore, in general, it is unavoidable that the factors described above affect the viscosity.
The adjusting factor of the viscosity depends on the concentration of the activator, and therefore, the concentration of the base is usually lower than a certain concentration in order to maintain the handling during production, transportation or shampoo production. Yes, and generally from a practical point of view, the active agent concentration in the aqueous solution is 25-30% by weight. In particular, the amide amino acid type activator of the formula (1) tends to have a high viscosity, and it has been difficult to increase the concentration.

[Means for solving the problem]

In view of the above situation, the present inventors have made intensive studies on a method of increasing the concentration of an amide amino acid type surfactant, which is easy to handle, and has a constant and stable viscosity. It has been found that these objects can be achieved by adding a polar solvent of the formula (1), and the present invention has been completed.

That is, the present invention provides a method of reacting an alkylimidazoline or amidoamine with a monohalogenated acetic acid or a salt thereof to obtain a compound represented by the general formula (1) (In the formula (1), R represents an alkyl group, a hydroxyalkyl group, an alkenyl group, or an aralkyl group having 7 to 23 carbon atoms, and M represents an alkali metal atom, an ammonium group, or a cation residue of an alkanolamine.) The amide amino acid type activator represented and / or general formula (2) (In the formula (2), R and M are the same as in the formula (1)) In a method for producing an amphoteric surfactant composition containing an amide amino acid type surfactant represented by the following formula: Adding at least one polar solvent selected from the group consisting of 1,3-butanediol, 1,4-butanediol and propylene glycol to form the amide amino acid type activator
An object of the present invention is to provide a method for producing an amphoteric surfactant composition, comprising obtaining an amphoteric surfactant composition containing 20 to 50% by weight and 2 to 10% by weight of the polar solvent.

The amide amino acid type activator represented by the general formula (1) or (2) is obtained by reacting an alkyl imidazoline or an amidoamine with a monohalogenated acetic acid or a salt thereof according to a known method.

Alkyl imidazoline or amidoamine which is a raw material of the amide amino acid type activator according to the present invention is produced by a known method. For example, a fatty acid or a fatty acid ester is reacted with aminoethylethanolamine at a temperature of 90 to 170 ° C, and further reacted at a temperature of 230 ° C to obtain a condensation product represented by the general formula (3) (In the formula (3), R has the above-mentioned meaning) 2-alkyl-1- (2-hydroxyethyl) -2-imidazoline represented by the following formula is obtained, and further hydrolyzed with an aqueous alkali solution, or Methyl ester and aminoethylethanolamine in the presence of an alkali catalyst in the range of 50-120
By reacting at a temperature of ° C., the following amidoamine is obtained.

(Wherein, R has the above-mentioned meaning) As such a raw material amine, 1-hydroxyethyl-2
-Cocoyl imidazoline, 1-hydroxyethyl-2-
Undecyl imidazoline, 1-hydroxyethyl-2-
Heptadecyl imidazoline, N-lauroyl-N'-hydroxyethylethylenediamine, N-stearoyl-
N'-hydroxyethylethylenediamine and the like can be mentioned.

Examples of monohalogenated acetic acid include sodium or potassium monochloroacetate, sodium or potassium monobromoacetate, and the like.

The method of reacting these monohalogenated acetic acid or a salt thereof with an alkyl imidazoline or amidoamine will be specifically described. In the case of producing an amide amino acid type activator represented by the general formula (1), imidazoline is used as a raw material amine. If used, imidazoline in aqueous alkaline solution 80-
Ring opening is performed at 90 ° C. to give amidoamine. 1 mol of this raw material amidoamine and at least 1 mol, preferably 1 to 3 mol, of a previously prepared monohalogenated acetic acid or a salt thereof are charged and stirred at 50 to 100 ° C., preferably 60 to 80 ° C. with an aqueous solution. After the reaction, the alkali is added dropwise so that the pH of the reaction solution is kept in the range of 8 to 9, or after the raw material amidoamine is charged together with a monohalogenated acetic acid or a salt thereof and an alkali such as sodium carbonate, The reaction is carried out with stirring at 50 to 100 ° C, preferably 60 to 80 ° C. When the reaction temperature is 40 ° C. or lower, the raw material amidoamine is hardly dissolved, and the reaction rate of the raw material amidoamine to the amphoteric compound becomes slow.
On the other hand, if the temperature is higher than 100 ° C., the coloring and decomposition of the amphoteric surfactant become severe, which is not preferable. Examples of the alkali include sodium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate and the like.

When producing the activator represented by the general formula (2), imidazoline or the amidoamine 1 represented by the general formula (5) is used.
The reaction may be carried out by reacting a mole with an aqueous solution of monohalogenated acetic acid or a salt thereof 2 to 3 moles.

The composition of the present invention contains, in addition to 20 to 50% by weight of the amphoteric surfactant, one or more polar solvents selected from 1,3-butanediol, 1,4-butanediol, and propylene glycol. -10% by weight. The polar solvent may be added at the time of the reaction or after the reaction, but is preferably added at the time of the reaction.

In order to achieve viscosity reduction and concentration, it is necessary to specify the compounding ratio of the amide amino acid type surfactant and the polar solvent.

When the mixing ratio of the polar solvent used in the present invention deviates from the above range, for example, when less than 2% by weight,
It is difficult to increase the concentration of the effective component and to reduce the viscosity. If the mixing ratio is more than 10% by weight, the solubility of salt produced as a by-product at the time of production is inhibited, and as a result, salt is precipitated, which is not preferable in handling. . In addition, the function of the amide amino acid type surfactant in the shampoo system may be hindered.

The polar solvent used in the present invention may be used alone or as a mixture without departing from the above range.

〔The invention's effect〕

According to the present invention, concentration of an amide amino acid-type surfactant, which has been extremely difficult in the past, can be easily achieved, and the operation is easy, which is suitable for industrial implementation. .

The amide amino acid type surfactant composition obtained by the present invention has extremely low viscosity in an aqueous solution thereof, so that it is extremely easy to handle and can be concentrated. This is advantageous in terms of production efficiency and transportation costs.

〔Example〕

Next, the present invention will be described based on examples, but the scope of the present invention is not limited by these. The percentages in the examples are% by weight unless otherwise specified.

Example 1 A four-necked flask equipped with a stirrer, a condenser, a dropping funnel, and a thermometer was charged with 268 g (1 mol) of 1-hydroxyethyl-2-undecylimidazoline, 90 g of water, and 2 g of sodium hydroxide.
g was heated to 80 ° C. with stirring, and stirring was continued for about 2 hours at the same temperature to open the ring of imidazoline.
Next, a separately prepared solution of 134 g (1.2 mol) of sodium monochloroacetate and 219 g of water was charged, and then 82 g of propylene glycol was added to the container. Then raise the temperature of the solution to 70-80 ° C
, 120 g of 40% sodium hydroxide was added dropwise over 3 hours. After completion of the dropwise addition, the mixture was further aged at a temperature of 75 to 80 ° C for 4 hours, and then cooled to room temperature. Thereafter, the reaction mixture was transferred to a tall beaker, and the viscosity was measured using a B-type viscometer while maintaining the temperature of the reaction mixture at 25 ° C. The viscosity was 50 cp. The reaction mixture was analyzed by high performance liquid chromatography to find that N-lauroyl-
It was confirmed that the mixture was a mixture of about 40% aqueous solution mainly containing N'-hydroxyethyl-N'-sodium carboxymethylethylenediamine.

Example 2 The same procedure as in Example 1 was carried out except that the amount of propylene glycol added was changed, and the results of examining the relationship with viscosity are shown in Table 1 together with the results of Example 1.

The composition of the reaction product was adjusted so that the content of N-lauroyl-N'-hydroxyethyl-N'-sodium carboxymethylethylenediamine was about 40%, and that of propylene glycol was adjusted so that the water had the composition shown in the above table.

As is clear from Table 1, the viscosity of the amidoamino acid type surfactant composition to which propylene glycol was added was extremely low, showing a clear difference as compared with Comparative Example 1 (non-addition type).

Comparative Example 1 In a four-necked flask equipped with a stirrer, a condenser, a dropping funnel and a thermometer, 268 g (1 mol) of 1-hydroxyethyl-2-laurylimidazoline, 90 g of water and 2 g of sodium hydroxide were placed.
Was heated to 80 ° C. with stirring, and stirring was continued for about 2 hours at the same temperature to open the ring of imidazoline. Next, a separately prepared solution of 139.8 g (1.2 mol) of sodium monochloroacetate and 295 g of water was charged in a container. Next, while maintaining the temperature of the solution at 70 to 80 ° C, 120 g of 40% sodium hydroxide was added dropwise over 3 hours. After completion of the dropwise addition, the mixture was further aged at a temperature of 75 to 80 ° C. for 4 hours and cooled to room temperature. Thereafter, the reaction mixture was transferred to a tall beaker and the temperature of the reaction mixture was raised to 25.
The viscosity was measured using a B-type viscometer while maintaining the temperature at ° C.
The viscosity was 25000 cp. The reaction mixture was analyzed by high performance liquid chromatography to confirm that the mixture was a mixture of about 40% aqueous solution mainly containing N-lauroyl-N'-hydroxyethyl-N'-sodium carboxymethylethylenediamine.

Example 3 10 g of 1,3-butanediol and 1,4-butanediol were added to 100 g of the reaction mixture of Comparative Example 1, and the viscosities were measured using a B-type viscometer. .

Claims (1)

(57) [Claims] An alkylimidazoline or amidoamine is reacted with a monohalogenated acetic acid or a salt thereof to obtain a compound represented by the general formula (1): (In the formula (1), R represents an alkyl group, a hydroxyalkyl group, an alkenyl group, or an aralkyl group having 7 to 23 carbon atoms, and M represents an alkali metal atom, an ammonium group, or a cation residue of an alkanolamine.) The amide amino acid type activator represented and / or general formula (2) (In the formula (2), R and M are the same as in the formula (1)) In a method for producing an amphoteric surfactant composition containing an amide amino acid type surfactant represented by the following formula: Adding at least one polar solvent selected from the group consisting of 1,3-butanediol, 1,4-butanediol and propylene glycol to form the amide amino acid type activator
A method for producing an amphoteric surfactant composition, comprising obtaining an amphoteric surfactant composition containing 20 to 50% by weight and 2 to 10% by weight of the polar solvent.