JPH08268982A - Production of benzalkonium-based cationic surfactant - Google Patents

Abstract

PURPOSE: To obtain a benzalkonium-based cationic surfactant, good in odor and useful as a base for uses of cosmetics and household necessaries by reducing a tertiary amine which is a raw material, then quaternizing the reduction product with a benzyl halide and distilling off low-boiling substances by distillation. CONSTITUTION: (A) A tertiary amine of formula I (R<1> is a 6-22C straight-chain or branched alkyl, alkenyl or alkylphenyl; R<2> and R<3> are each a 1-18C straight- chain or branched alkyl) is treated with (B) a reducing agent and the resultant reduction product is then reacted with (C) a benzyl halide of formula II (X is a halogen) in water. Low-boiling substances are subsequently distilled away by distillation using (D) steam or water in an amount of 10-500wt.% based on a benzalkonium-based cationic surfactant of formula III (preferably a compound of formula IV) to afford (E) the benzalkonium-based cationic surfactant. Furthermore, the surfactant is obtained by reacting the components (A) with (C) in the presence of the reducing agent and an antioxidant in water and then similarly treating the resultant reactional product with the component (D).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a benzalkonium-based cationic surfactant, and more particularly to a method for producing a benzalkonium-based cationic surfactant having a good odor.

[0002]

PRIOR ART AND PROBLEMS TO BE SOLVED BY THE INVENTION Among benzalkonium-based cationic surfactants, those having a long-chain alkyl group are useful as a base for hair rinses, and have softness and slipperiness on hair. It is widely used because it can impart antistatic properties. In addition, it is known that those having a short alkyl group have extremely excellent bactericidal properties, and application thereof utilizing the bactericidal power is being widely studied in cosmetics and household products.

Since products using these benzalkonium-based cationic surfactants are usually perfumed with various fragrances according to the taste of the consumer, the benzalkonium-based cationic surfactant aqueous solution is odorless or limited. It is strongly desired to have a slight odor that is almost odorless.
In particular, a benzalkonium-based cationic surfactant having a short alkyl group, which is excellent in bactericidal effect, has a bad odor as compared with a surfactant having a long chain alkyl group, and improvement of the odor is strongly desired.

The benzalkonium-based cationic surfactant is usually produced by reacting a tertiary amine with a benzyl halide directly or in the presence of a solvent. In the reaction of a tertiary amine with benzyl halide, if an excess amount of amine is used, the amine that cannot be easily removed industrially remains in the product and deteriorates the odor. Therefore, benzyl halide is generally used in a slight excess amount. The reaction is taking place in the system. It is known that even if a large excess of benzyl halide is used, a small amount of amine remains, but it is said that this does not adversely affect the odor if it is below a certain amount.
Then, the problem is benzyl halide and impurities by-produced from it, and these are considered to be the largest cause of deteriorating odor.

Conventionally, as methods for removing these impurities and improving odor, steam distillation, adsorption treatment with an adsorbent, recrystallization, and treatment with a reducing agent such as sodium borohydride are known after the reaction. There is. But,
In the method of ~, the problem is that the odor worsens over time, and when trying to completely eliminate the odor by the method of, it takes a lot of time and is inappropriate from the viewpoint of productivity. The method has a problem that the yield is lowered and the manufacturing process is complicated in industry. Method is more effective in removing odors than method ~,
A large amount of reducing agent is required to suppress the odor only by the method of 1., and when a large amount of reducing agent is used, there is a problem that the reducing agent remains and decolorization of the dye occurs when blended into the product. So far, no effective deodorizing method has been found.

[0006]

Means for Solving the Problems As a result of intensive investigations under such circumstances, the present inventors have found that after treating a starting material tertiary amine with a reducing agent, it is quaternized with benzyl halide and a low boiling point is obtained by distillation. After distilling off, or after reacting the tertiary amine and benzyl halide in the presence of a reducing agent, an antioxidant or a mixture thereof, benzalco having an excellent odor can be obtained by distilling off a low boiling point. The present invention has been completed by the finding that a cationic cationic surfactant can be obtained. That is, the present invention, the general formula (1)

[0007]

Embedded image

(In the formula, R ¹ represents a linear or branched alkyl group having 6 to 22 carbon atoms, an alkenyl group or an alkylphenyl group, and R ² and R ³ are the same or different and have 1 carbon atoms.
18 linear or branched alkyl groups are shown. ) The tertiary amine represented by the formula (2) is treated with a reducing agent and then treated with water in the general formula (2).

[0009]

[Chemical 6]

## STR1 ## where X is halogen, the reaction is performed with a benzyl halide, and then steam or water is added to the benzalkonium-based cationic surfactant.
Characterized by distilling low-boiling components by distillation using 10 to 500% by weight, the general formula (3)

[0011]

[Chemical 7]

The present invention provides a method for producing a benzalkonium-based cationic surfactant represented by the formula (wherein R ¹ , R ² , R ³ and X have the above-mentioned meanings).

In the present invention, the tertiary amine represented by the general formula (1) and the benzyl halide represented by the general formula (2) are mixed with a reducing agent, an antioxidant or a mixture thereof in water. 10 to 500% by weight of steam or water based on the benzalkonium-based cationic surfactant
Characterized by distilling off low-boiling components by the used distillation,
The present invention provides a method for producing a benzalkonium-based cationic surfactant represented by the general formula (3).

The tertiary amine represented by the general formula (1) used in the present invention includes dimethylhexylamine,
Dimethyloctylamine, dimethyldecylamine, dimethyldodecylamine, dimethyltetradecylamine, dimethylhexadecylamine, dimethyloctadecylamine, dimethyloctadecenylamine, dimethyldecenylamine, dimethyldodecenylamine, dimethyltetradecenylamine, dimethyl Hexadecenylamine, dimethyloleylamine, diethylhexylamine, diethyloctylamine, diethyldecylamine, diethyldodecylamine, diethyltetradecylamine, diethylhexadecylamine, diethyloctadecylamine, N-
Methyl-N-hexadecyl-octadecylamine and the like can be mentioned, but it is preferable that R ¹ is a linear or branched alkyl group having 6 to 10 carbon atoms, particularly 8 carbon atoms, and R ² and R ³ are methyl groups.

Specific examples of the reducing agent used in the present invention include hydrogen, sodium sulfite, potassium sulfite, sodium thiosulfate, potassium thiosulfate, borohydride salt, and aluminum hydride salt. formula
(5) M (BH ₄ ) _x (5) (wherein M is an alkali metal, Ca, Zn or (CH ₃ ) ₄ N, and when M is an alkali metal or (CH ₃ ) ₄ N, x is 1 , M
X is 2 when Ca or Zn. ) A borohydride salt represented by Specific examples of the borohydride salt represented by the general formula (5) include lithium borohydride, sodium borohydride, potassium borohydride, tetramethylammonium borohydride, calcium borohydride or hydrogenated borohydride. Examples thereof include zinc borohydride, and sodium borohydride is particularly preferable. The reducing agent remains powder,
Alternatively, it is added in the form of an aqueous solution or an aqueous alkaline solution.

Specific examples of the antioxidant used in the present invention include ascorbic acid, sodium ascorbate, stearic acid ascorbate, erythorbic acid, sodium erythorbate, calcium disodium ethylenediaminetetraacetate, and ethylenediaminetetrasodium. Examples include disodium acetate, guaiac butter, isopropyl citrate, dibutylhydroxytoluene, tocopherol, nordihydroguaiaretic acid, butylhydroxyanisole, and propyl gallate. Among these, compounds having a phenol ring such as dibutylhydroxytoluene, tocopherol, butylhydroxyanisole, and propyl gallate are preferable.

Examples of the benzyl halide represented by the general formula (2) used in the present invention include benzyl chloride and benzyl bromide, with benzyl chloride being preferred. Further, the general formula obtained by the method of the present invention
The benzalkonium-based cationic surfactant represented by (3) is preferably a compound represented by the following general formula (4).

[0018]

Embedded image

(In the formula, R ⁴ represents a linear or branched alkyl group having 6 to 10 carbon atoms, and X represents the above-mentioned meaning.) In the present invention, the tertiary represented by the general formula (1) When the amine is treated with a reducing agent, the amount of the reducing agent added is preferably 0.001 to 5% by weight, more preferably 0.01 to 2% by weight, based on the tertiary amine. The treating temperature of the reducing agent is preferably 0 to 200 ° C, more preferably 20 to 80 ° C. The reducing agent may be added all at once or in portions. After adding the reducing agent, stirring or aging is carried out for 10 minutes or longer, preferably 30 minutes or longer.

When the tertiary amine represented by the general formula (1) is reacted with the benzyl halide represented by the general formula (2) in the presence of a reducing agent, an antioxidant or a mixture thereof, the reduction is performed. The amount of the agent, antioxidant or mixture thereof added is preferably 0.001 to 5% by weight, more preferably 0.01 to 2% by weight, based on the tertiary amine. The reducing agent, antioxidant, or mixture thereof may be added all at once or in divided portions. Furthermore, the raw material tertiary amine may be combined with a reducing agent, and such a combination further improves the deodorizing effect.

The reaction temperature for the quaternization reaction of the tertiary amine represented by the general formula (1) with the benzyl halide represented by the general formula (2) is 0 to 100 ° C, preferably 5 to 80 ° C. More preferably, it is 15 to 65 ° C. Benzyl halide is 1.005 to 1.3 moles, preferably 1.007 to 1 mole of tertiary amine.
Using 1.15 mol, more preferably 1.009 to 1.11 mol, benzyl halide is added dropwise to the suspension of the tertiary amine and water.
The dropping time is preferably 0.5 to 2 hours, and if the dropping is earlier than 0.5 hours, the reaction occurs at a short time after the dropping is completed and the reaction temperature cannot be controlled, and if it is 2 hours or more, the productivity is lowered, which is not preferable. . Water to be charged with the tertiary amine at the initial stage is preferably used so that the benzalkonium-based cationic surfactant has a concentration of 50 to 80% by weight as a reaction product. If the concentration is less than 50% by weight, the productivity will be reduced, and if it exceeds 80% by weight, side reactions will be abundant and the odor will be bad, such being undesirable. The aging time for the quaternization reaction is
The time until the residual amine value becomes 1.5 KOHmg / g or less, that is, 1 to 10 hours is preferable, and 3 to 5 hours is more preferable. During the reaction, if the pH in the system drops and the pH drops to 7 or lower, the reaction rate will drop, and a large amount of benzyl halide, which causes odor, will remain. Therefore, should the pH be adjusted to pH 7 or higher, preferably pH 8 or higher? Alternatively, it is preferable to use a buffer such as Na ₂ CO ₃ . Further, when the reducing agent treatment of the tertiary amine or the quaternization reaction is performed in the system under a nitrogen atmosphere, the odor is more effectively improved.

After the completion of the quaternization reaction, distillation is carried out, which may be either steam distillation while introducing steam or water (hereinafter referred to as steaming) or simple distillation (hereinafter referred to as topping). This steaming or topping is performed at a temperature of 40 to 100 ° C, preferably 50 to 80 ° C.
C, pressure 0.01 ~ 760 mmHg, preferably 50 ~ 200 mmHg while introducing steam or water while operating to adjust the amount of steam or water introduced and the amount of introduced steam or water to keep the concentration in the system constant, Alternatively, a certain amount of water is charged, and then water is distilled off so that the concentration of the benzalkonium-based cationic surfactant becomes 50 to 80% by weight. The amount of steam or water to be introduced is 10 to 500% by weight, preferably 100 to 300% by weight, based on the benzalkonium-based cationic surfactant. If it is less than 10% by weight, sufficient odor is not improved, and if it exceeds 500% by weight, the productivity is lowered, which is not preferable.

[0023]

EFFECTS OF THE INVENTION According to the present invention, a benzalkonium-based cationic surfactant having an excellent odor can be obtained very easily and industrially without any problem, and it is very preferable as a base for cosmetics and household products. . As a result, there is an effect that a small amount of fragrance can be used for perfume.

[0024]

EXAMPLES The present invention will now be specifically described with reference to examples, but the present invention is not limited thereto. still,
Unless otherwise specified,% in the examples is based on weight.

Comparative Example 1 Dimethyloctylamine (MW = 160.35, trade name: Pharmin DMO8P) 320.7 g (2.0 mol) and 224.24 g of water were placed in a 1-liter four-necked flask and benzyl chloride (MW = 126.59) was stirred at room temperature. ) 255.7 g (2.02 mol) of 1
It dripped over time. After that, the pH in the system was adjusted to 8 to 9 and aging was carried out for 5 hours. The analytical values of the dimethyloctylbenzalkonium salt thus obtained are shown in Table 1. The analytical values in Table 1 are measured by the following method. Effective content: Cation% (JP method) Moisture: Karl Fischer method Residual amine value: HCl titration method Benzyl chloride: HPLC

[0026]

[Table 1]

Comparative Example 2 320.7 g (2.0 mol) of dimethyloctylamine (MW = 160.35, trade name: Pharmin DMO8P) and 224.24 g of water were placed in a 1-liter four-necked flask and stirred at room temperature with benzyl chloride (MW = 126.59). ) 255.7 g (2.02 mol) was added dropwise over 1 hour. After that, the system was aged for 5 hours while adjusting the pH to 8-9, and the low boiling point was distilled off at 60 ° C. and 100 mmHg while blowing steam into the obtained 70% aqueous solution. The amount of steam was 1792.2 g (300% based on the benzalkonium-based cationic surfactant). At this time, the amounts of the distillate and the steam were the same so that the concentration in the system was constant. The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analytical values were as shown in Table 2.

[0028]

[Table 2]

Comparative Example 3 320.7 g (2.0 mol) of dimethyloctylamine (MW = 160.35, trade name: Pharmin DMO8P) and 224.24 g of water were placed in a 1-liter four-necked flask and stirred at room temperature with benzyl chloride (MW = 126.59). ) 255.7 g (2.02 mol) of 1
It dripped over time. After that, the system was aged for 5 hours while adjusting the pH to 8-9, and the low boiling point was distilled off at 60 ° C. and 100 mmHg while blowing steam into the obtained 70% aqueous solution. The amount of steam was 864.6 g (150% based on the benzalkonium-based cationic surfactant). At this time, the amounts of the distillate and the steam were the same so that the concentration in the system was constant. The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analytical values were as shown in Table 3.

[0030]

[Table 3]

Comparative Example 4 320.7 g (2.0 mol) of dimethyloctylamine (MW = 160.35, trade name: Pharmin DMO8P) and 224.24 g of water were placed in a 1-liter four-necked flask and stirred at room temperature with benzyl chloride (MW = 126.59). ) 255.7 g (2.02 mol) of 1
It dripped over time. After that, the system was aged for 5 hours while adjusting the pH to 8-9, and the low boiling point was distilled off at 60 ° C. and 100 mmHg while blowing steam into the obtained 70% aqueous solution. The amount of steam was 28.8 g (5% based on the benzalkonium-based cationic surfactant). At this time, the amounts of the distillate and the steam were the same so that the concentration in the system was constant.
The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analysis values are shown in Table 4.
It was as shown in.

[0032]

[Table 4]

Comparative Example 5 320.7 g (2.0 mol) of dimethyloctylamine (MW = 160.35, trade name: Pharmin DMO8P) and 224.24 g of water were placed in a 1-liter four-necked flask and benzyl chloride (MW = 126.59) was stirred at room temperature. ) 255.7 g (2.02 mol) of 1
It dripped over time. After that, the system was aged for 5 hours while adjusting the pH of the system to 8-9, and the low boiling component was distilled off at 60 ° C. and 100 mmHg while dropping water into the obtained 70% aqueous solution. The amount of water was 1792.2 g (300% based on the benzalkonium-based cationic surfactant). At this time, the amounts of the distillate and water were the same so that the concentration in the system was constant. The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analytical values were as shown in Table 5.

[0034]

[Table 5]

Comparative Example 6 320.7 g (2.0 mol) of dimethyloctylamine (MW = 160.35, trade name: Pharmin DMO8P) and 0.32 g of sodium borohydride were placed in a 1-liter four-necked flask and heated at 30 ° C.
After stirring for 2 hours with water, 224.24 g of water was added, and while stirring, 255.7 g (2.02 mol) of benzyl chloride (MW = 126.59) was added.
Was added dropwise over 1 hour. After that, the mixture was aged at 60 ° C. for 5 hours while adjusting the pH to 8-9. The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analytical values were as shown in Table 6.

[0036]

[Table 6]

Comparative Example 7 Dimethyloctylamine (MW = 160.35, trade name: Pharmin DMO8P) 320.7 g (2.0 mol), dibutylhydroxytoluene 0.32 g and water 224.24 g were placed in a 1 liter four-necked flask and stirred at room temperature. Meanwhile, 255.7 g (2.02 mol) of benzyl chloride (MW = 126.59) was added dropwise over 1 hour. After that, the mixture was aged at 60 ° C. for 5 hours while adjusting the pH to 8-9. The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analytical values were as shown in Table 7.

[0038]

[Table 7]

Comparative Example 8 The same operation as in Comparative Example 7 was carried out except that sodium borohydride was used instead of dibutylhydroxytoluene. The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analysis values were as shown in Table 8.

[0040]

[Table 8]

Comparative Example 9 320.7 g (2.0 mol) of dimethyloctylamine (MW = 160.35, trade name: Pharmin DMO8P) and 0.32 g of sodium borohydride were placed in a 1-liter four-necked flask and heated to 30 ° C.
After stirring for 2 hours at room temperature, 224.24 g of water was charged into a 1-liter four-necked flask, and 255.7 g (2.02 mol) of benzyl chloride (MW = 126.59) was added dropwise over 1 hour while stirring at room temperature. After that, the pH was adjusted to 8 to 9 and the mixture was aged at 60 ° C. for 5 hours. While blowing steam into the obtained 70% aqueous solution, low boiling components were distilled off at 60 ° C. and 100 mmHg. The amount of steam was 28.8 g (5% based on the benzalkonium-based cationic surfactant). At this time, the amounts of the distillate and the steam were the same so that the concentration in the system was constant. The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analytical values were as shown in Table 9.

[0042]

[Table 9]

Example 1 320.7 g (2.0 mol) of dimethyloctylamine (MW = 160.35 trade name: Pharmin DMO8P) and 0.32 g of sodium borohydride were placed in a 1-liter four-necked flask and heated to 50 ° C.
After stirring for 2 hours at room temperature, 224.24 g of water was charged into a 1-liter four-necked flask, and 255.7 g (2.02 mol) of benzyl chloride (MW = 126.59) was added dropwise over 1 hour while stirring at room temperature. After that, the pH was adjusted to 8 to 9 and the mixture was aged at 60 ° C. for 5 hours. While blowing steam into the obtained 70% aqueous solution, low boiling components were distilled off at 60 ° C. and 100 mmHg. The amount of steam was 1792.2 g (300% based on the benzalkonium-based cationic surfactant). At this time, the amounts of the distillate and the steam were the same so that the concentration in the system was constant. The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analytical values were as shown in Table 10.

[0044]

[Table 10]

Example 2 320.7 g (2.0 mol) of dimethyloctylamine (MW = 160.35 trade name: Pharmin DMO8P), 0.32 g of dibutylhydroxytoluene and 224.24 g of water were placed in a 1-liter four-necked flask and stirred at room temperature. Meanwhile, 255.7 g (2.02 mol) of benzyl chloride (MW = 126.59) was added dropwise over 1 hour. After that, the pH was adjusted to 8 to 9 and the mixture was aged at 60 ° C. for 5 hours. While blowing steam into the obtained 70% aqueous solution, low boiling components were distilled off at 60 ° C. and 100 mmHg. The amount of steam was 1792.2 g (300% based on the benzalkonium-based cationic surfactant). At this time, the amounts of the distillate and the steam were the same so that the concentration in the system was constant. The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analytical values were as shown in Table 11.

[0046]

[Table 11]

Example 3 The same operation as in Example 2 was carried out except that butylhydroxyanisole was used instead of dibutylhydroxytoluene. The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analytical values were as shown in Table 12.

[0048]

[Table 12]

Example 4 The same operation as in Example 2 was carried out except that tocopherol was used instead of dibutylhydroxytoluene. The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analytical values were as shown in Table 13.

[0050]

[Table 13]

Example 5 320.7 g (2.0 mol) of dimethyloctylamine (MW = 160.35, trade name: Pharmin DMO8P) and 0.32 g of sodium borohydride were placed in a 1-liter four-necked flask and heated to 50 ° C.
After stirring at room temperature for 2 hours, dibutylhydroxytoluene 0.32
g and 224.24 g of water were charged into a 1-liter four-necked flask, and benzyl chloride (MW = 126.
59) 255.7 g (2.02 mol) was added dropwise over 1 hour. Then, while adjusting the pH to 8-9, aging for 5 hours at 60 ℃, while blowing steam into the resulting 70% aqueous solution, at 60 ℃,
The low boiling point was distilled off at 100 mmHg. The amount of steam is 1792.2
g (300 for benzalkonium-based cationic surfactant)
%)Met. At this time, the amounts of the distillate and the steam were the same so that the concentration in the system was constant. The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analytical values were as shown in Table 14.

[0052]

[Table 14]

Example 6 The same operation as in Example 5 was carried out except that sodium borohydride was used instead of dibutylhydroxytoluene. The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analysis values are shown in Table 15.
It was as shown in.

[0054]

[Table 15]

Example 7 320.7 g (2.0 mol) of dimethyloctylamine (MW = 160.35, trade name: Pharmin DMO8P) and 0.32 g of sodium borohydride were placed in a 1-liter four-necked flask and heated to 50 ° C.
After stirring for 2 hours at room temperature, 224.24 g of water was charged into a 1-liter four-necked flask, and 255.7 g (2.02 mol) of benzyl chloride (MW = 126.59) was added dropwise over 1 hour while stirring at room temperature. Then, while adjusting the pH to 8-9, aging for 5 hours at 60 ℃, while adding water to the resulting 70% aqueous solution,
The low-boiling components were distilled off at 60 ° C and 100 mmHg. The amount of water is 1792.2
g (300 for benzalkonium-based cationic surfactant)
%)Met. At this time, the amounts of the distillate and water were the same so that the concentration in the system was constant. The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analytical values were as shown in Table 16.

[0056]

[Table 16]

Example 8 The same operation as in Example 1 was carried out except that the amount of steam was 150% with respect to the benzalkonium-based cationic surfactant.
The dimethyloctylbenzalkonium salt thus obtained was analyzed in the same manner as in Comparative Example 1, and the analysis values are shown in Table 1.
It was as shown in 7.

[0058]

[Table 17]

The odor of a 1% aqueous solution of the dimethyloctylbenzalkonium salt obtained in Examples 1 to 8 and Comparative Examples 1 to 9 was evaluated according to the following criteria. The results are shown in Table 18.・ Odor evaluation: ◎ No specific odor ○ No specific odor ○ to ○ △ Slight specific odor ○ △ Slight specific odor △ Large specific odor × Specific odor Extremely high level that can be used as a product ○ to ○ △ That is all.

[0060]

[Table 18]

Claims (5)

[Claims] 1. A general formula (1): (In the formula, R ¹ represents a linear or branched alkyl group having 6 to 22 carbon atoms, an alkenyl group, or an alkylphenyl group,
R ² and R ³ are the same or different and each represents a linear or branched alkyl group having 1 to 18 carbon atoms. ) The tertiary amine represented by the formula (1) is treated with a reducing agent, and then treated with water in the general formula (2) (Wherein X represents halogen), and then steam or water is reacted in an amount of 10 to 500% by weight with respect to the benzalkonium-based cationic surfactant.
Characterized by distilling off low-boiling components by the used distillation,
General formula (3) (In the formula, R ¹ , R ² , R ³ and X have the above-mentioned meanings.) A method for producing a benzalkonium-based cationic surfactant. 2. A reaction between a tertiary amine represented by the general formula (1) and a benzyl halide represented by the general formula (2) in water in the presence of a reducing agent, an antioxidant or a mixture thereof. And then removing low boiling components by distillation using steam or water in an amount of 10 to 500% by weight with respect to the benzalkonium-based cationic surfactant, which is represented by the general formula (3). A method for producing a ruconium-based cationic surfactant. 3. A benzalkonium-based cationic surfactant represented by the general formula (3) has the general formula (4): The production method according to claim 1 or 2, wherein the compound is represented by the formula (wherein R ⁴ represents a linear or branched alkyl group having 6 to 10 carbon atoms, and X represents the above meaning). 4. The reducing agent is represented by the general formula (5) M (BH ₄ ) _x (5) (wherein M is an alkali metal, Ca, Zn or (CH ₃ ) ₄ N, and M is an alkali metal or When (CH ₃ ) ₄ N, x is 1, M is
X is 2 when Ca or Zn. ) It is a borohydride salt represented by these, The manufacturing method as described in any one of Claims 1-3. 5. The production method according to claim 2, wherein the antioxidant is a compound having a phenol ring.