JPS62116698A - High concentration aqueous solution of alpha-sulfo-fatty acid ester - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a highly concentrated aqueous solution of α-sulfo fatty acid ester salt having low viscosity and high fluidity.

[Conventional technology and problems]

Currently, most powdered or granular detergents that are widely used for industrial or household purposes are manufactured by spray-drying a slurry containing detergent components such as activators.

The neutralized activator used in this slurry is desirably as high in activator content as possible and as low in volatile components such as water, in order to improve the degree of freedom in mixing detergents during slurry production.

However, in this technical field, the proportion of surfactant in a highly concentrated neutralized aqueous solution that can be handled industrially is about 25% by weight for α-sulfo fatty acid ester salts. When this concentration is exceeded, the viscosity increases rapidly and handling becomes extremely difficult, causing many problems in workability and handling.

Various proposals have been made to solve these problems. For example, in JP-A-57-7462 and JP-A-59-74195, a conventionally known lower alcohol is used as an essential thinner in order to improve fluidity. Furthermore, JP-A-58-118899 and JP-A-59-157199 disclose certain ethoxylates, for example, in the former case, EO adducts of alkylphenols or aliphatic alcohols, or polyethylene glycol or polypropylene glycol of a specific molecular weight,
In the latter case, partially unsaturated alcohols or their E○ adducts or their PO/EO adducts, and even branched alcohols with E
O adducts are described as viscosity modifiers.

JP-A-59-98187 describes that certain carboxylates and/or esters, particularly methyl α-sulfoacetate, sodium chloroacetate, and ethyl cyanoacetate, are effective as viscosity modifiers.

However, many of the additives disclosed in the literature have various problems, such as ingredients unrelated to cleaning, and lower alcohols and others lower the flash point.
The current situation is that it does not meet the demand for practical high concentration.

[Means for solving problems]

The present inventors have conducted extensive research in order to obtain a highly concentrated aqueous solution of α-sulfo fatty acid ester salt that improves the conventional drawbacks. By containing 0.1 to 15% by weight of polyoxyalkylene-added polyhydric alcohol, it has excellent detergency, even when the concentration of the active ingredient (α-sulfo fatty acid ester salt) is in the range of 30 to 60% by weight. It was discovered that a highly concentrated aqueous solution that is sufficiently handleable and stable for long-term storage can be obtained, leading to the completion of the present invention.

That is, the present invention provides alpha-sulfo fatty acid ester salts of 30 to 60
% by weight, an inorganic sulfate 0.2-30% by weight and a polyoxyalkylene-added polyhydric alcohol 0.1-15% by weight. be.

Note that the α-sulfo fatty acid ester salt, which is the active ingredient of the highly concentrated aqueous solution of the present invention, contains a portion of the fatty acid ester salt decomposed to become a fatty acid salt, and the above concentration also includes this fatty acid salt. ing.

The α-sulfo fatty acid ester salt according to the present invention is preferably an α-sulfo fatty acid ester salt having a fatty acid composition of 6 to 24 carbon atoms, and is produced by a known method. For example, C
An example of this method is to sulfonate and ripen an ester having a fatty acid composition of 6 to CZ4 using SO3 gas, and then neutralize it with an alkali.

The ester having a fatty acid composition having 6 to 24 carbon atoms may be either natural or synthetic, or may be a mixture of esters having various carbon numbers. Generally, fatty acid esters derived from natural oils and fats are used alone or in combination. Examples of these esters include coconut oil fatty acid esters, palm kernel oil fatty acid esters, palm oil fatty acid esters, tallow fatty acid esters, and cured products thereof.

Among them, the fatty acid composition of the α-sulfo fatty acid ester salt is such that the ratio (weight ratio) of the α-sulfo fatty acid ester salt having 16 to 24 carbon atoms to the α-sulfo fatty acid ester salt having 6 to 15 carbon atoms is 10010 to 80/20. Products within this range have high cost benefits, such as achieving high concentration and excellent detergency. When the proportion of α-sulfo fatty acid ester salt having a fatty acid composition having 16 to 24 carbon atoms is less than 50% by weight,
It is preferable that this ratio is large, since the cleaning performance will be significantly reduced and also from the viewpoint of raw material cost. Particularly preferably 10
The range is from 010 to 90/10.

The fatty acid composition of the α-sulfo fatty acid ester salt may be prepared using either fatty acid ester or α-sulfo fatty acid ester (sulfonic acid).

The alcohol moiety of the ester is a C1-C4 straight chain or branched alcohol, such as methyl, ethyl, n-propyl, i
-propyl and n-butyl, any of which is possible.

Neutralization with an alkali may be performed by adding the α-sulfo fatty acid ester to an aqueous alkali solution while stirring, but in order to minimize hydrolysis of the ester, the aqueous alkali solution and the α-sulfo fatty acid ester are supplied at the same time. pH3～
It is desirable to carry out continuous neutralization at step 7. Alkali is aqueous alkanolamine, ammonia, caustic alkali (NaO
H, KOH, Mg(OH)z, etc.) can be used. Neutralization temperature is 40-80°C, preferably 50-70°C
It is appropriate to set it at ℃. If the neutralization temperature is below 40°C, the viscosity will increase, making it difficult to handle the neutralized product, and if it is above 80°C, the decrease in ester content during neutralization will increase.

In the α-sulfo fatty acid ester salt, some of the esters are hydrolyzed during the neutralization process after sulfonation to become the α-sulfo fatty acid salt, and the ester content decreases, but from the viewpoint of cleaning performance,
Ester content is 50 to 100 mol%, preferably 80
A range of 100 mol % is desired. Ester content is 5
If it is less than 0 mol%, the detergency will be greatly reduced and the solubility in water will also be reduced. In addition, if the ester content is in the range of 50 to 100 mol%, a highly concentrated aqueous solution containing a predetermined amount of inorganic sulfate and polyoxyalkylene-added polyhydric alcohol and having a sufficiently low viscosity and an active ingredient concentration of 30% by weight or more can be obtained. It will be done.

Inorganic sulfates according to the present invention include sodium sulfate, sulfuric acid,
Refers to potassium, ammonium sulfate, magnesium sulfate, and sulfate alkanolamine salts.

Also, what is polyoxyalkylene-added polyhydric alcohol?
Refers to polyalkylene glycols represented by polyethylene glycol and polypropylene glycol, or alkylene oxide adducts of polyhydric alcohols such as glycerin, trimethylolpropane, pentaerythritol, and sorbitol. In particular, the molecular weight is 6000 or more, preferably 10
．． Polyethylene glycol or polypropylene glycol having a molecular weight of 1,000 to 20,000 or the polyhydric alcohol (trihydric or higher) alkylene oxide adduct having a molecular weight of 1,000 or more, preferably 1,500 to 20,000 show good results. Examples of the alkylene oxide include ethylene oxide and mixed alkylene oxides of ethylene oxide and propylene oxide, and the proportion of ethylene oxide is preferably 50% by weight or more, more preferably 70% by weight or more.

It is important that the inorganic sulfate is contained in a range of 0.2 to 30% by weight, and the polyoxyalkylene-adducted polyhydric alcohol is contained in a range of 0.1 to 15% by weight;
If the weight percent or polyoxyalkylene-added alcohol exceeds 15 weight percent, the composition becomes a paste with low fluidity. Particularly preferably 0.3 to 20% by weight of inorganic sulfate
, polyoxyalkylene addition polyhydric alcohol 0.1-1
It is 0% by weight.

The method of adding the inorganic sulfate and the polyoxyalkylene-adducted polyhydric alcohol is not particularly limited, but it is convenient to include a predetermined amount of the α-sulfo fatty acid ester in the alkaline aqueous solution during alkali neutralization. In this case, a predetermined amount of sulfate and polyoxyalkylene-added polyhydric alcohol may be added to the alkaline aqueous solution.

The highly concentrated aqueous solution of the present invention has sufficient fluidity and can be handled even when the concentration of α-sulfo fatty acid ester salt is 30 to 60% by weight.

Furthermore, in order to obtain a neutralized product with good fluidity, when the α-sulfo fatty acid ester salt concentration is in the range of 35 to 50% by weight, the α-sulfo fatty acid ester salt with a fatty acid composition of C6 to cps and the The weight ratio of the fatty acid composition to the α-sulfo fatty acid ester salt is within the range of 100:O to 90:10, and the sulfate is 0.2 to 20% by weight to the α-sulfo fatty acid ester salt high concentration aqueous solution. It is preferable that the polyoxyalkylene-added polyhydric alcohol is contained in a range of 0.1 to 10% by weight.

Depending on the composition, addition of sodium chloride can also give good results, further improving fluidity. The amount added is 0.
It is 1 to 10% by weight, preferably 0.5 to 10% by weight. In this case, sodium chloride is partially substituted for sulfate. Sodium chloride may be added as such, or
It may be produced as a by-product by decolorizing with sodium hypochlorite.

The components contained in the neutralized product of the present invention include the above-mentioned α-sulfo fatty acid ester salts (α-sulfo fatty acid ester salts and α-
In addition to sulfofatty acid salts (di-salts), impurities such as fatty acid salts, fatty acid esters, or methyl sulfates may be included, but these do not impair the effects of the present invention, and naturally the highly concentrated aqueous solution of the present invention It is located in Noriharu.

〔Effect of the invention〕

As described in detail above, the present invention discloses for the first time a highly concentrated aqueous solution of 30 to 60% by weight of α-sulfo fatty acid ester salt with a practical composition. This makes it possible to significantly reduce the per-spray drying cost.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.
The present invention is not limited to these examples.

Examples 1 to 18 Methyl esters with fatty acid compositions of 06 to CI5 and CI6 to CZa were each reacted using a conventional method (
After sulfonation at a reaction molar ratio S03/methyl ester=1.20), aging was performed at 80° C. for 1 hour to obtain methyl α-sulfofatty acid. One of the methyl α-sulfo fatty acids was neutralized as is, and the other was treated with 5% by weight of MeOH to increase the ester content, treated at 60°C for 10 minutes, and then neutralized. I got something. These neutralized products were freeze-dried to obtain powdered α-sulfo fatty acid methyl sodium salts having ester contents of about 80% and about 95% of the respective fatty acid compositions.

These powdered α-sulfo fatty acid methyl sodium salts are blended into a predetermined fatty acid composition, and an inorganic sulfate, a polyoxyalkylene-added polyhydric alcohol, and water are added to adjust the concentration to a predetermined active ingredient concentration, and the resulting neutralized product is obtained. The appearance and viscosity were measured. The results are shown in Tables 1-3.

Example 19 After sulfonating and aging methyl ester blended with a predetermined fatty acid composition in a continuous thin film sulfonation reactor, an alkaline aqueous solution containing a predetermined amount of sulfate and polyoxyalkylene-added polyhydric alcohol was used. , fully continuous type 1
Examples 1 to 6.14.1
Results comparable to those of 5 were obtained.

Example 20 Same as Example 19, but with MeO after sulfonation-ripening
Results comparable to Examples 7 to 13, 16, and 17 were also obtained for those treated with H to increase the ester content.

Claims (1)

[Claims] 1. Contains 30 to 60% by weight of α-sulfo fatty acid ester salt, 0.2 to 30% by weight of inorganic sulfate, and 0.1 to 15% by weight of polyoxyalkylene-added polyhydric alcohol. A highly concentrated aqueous solution of α-sulfo fatty acid ester salt. 2. α according to claim 1, wherein the polyoxyalkylene-added polyhydric alcohol is polyethylene glycol, polypropylene glycol, an alkylene oxide adduct of pentaerythritol, an alkylene oxide adduct of trimethylolpropane, or an alkylene oxide adduct of glycerin. - Highly concentrated aqueous solution of sulfo fatty acid ester salt.