JPH0633097A - Solid soap composition - Google Patents

Abstract

(57) [Summary] [Structure] In a solid soap composition based on a sodium salt of a partially hydrogenated fatty acid, a salt of one or more fatty acids selected from caprylic acid, pelargonic acid and capric acid is used. A solid soap composition containing 3 to 6% by weight of the amount of pre-fatty acid. [Effect] It is possible to effectively prevent cracking of the solid soap and improve the solubility in cold water.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a solid soap composition which prevents cracks (cracks) generated when a solid soap based on a sodium salt of a partially hydrogenated fatty acid is used and has improved dissolution in cold water. Regarding

[0002]

2. Description of the Related Art Bar soaps are required to have good basic foaming properties, cleansing properties, and action on the skin. In order to meet such requirements, it is generally practiced to blend a plurality of fatty acid salt derived from a raw material of fats and oils to adjust the properties. Among the oil and fat raw materials, beef tallow, lard, palm oil and the like are used for toilet soaps and the like because they have characteristics such as low irritation to the skin when made into a fatty acid salt, and fine bubbles, etc. Due to its high content of unsaturated fatty acid residues and problems with coloring, odor, storage stability, etc., it is often used after hydrogenation [eg Journal
Of American Oil Chemistry Society (J
AOCS), 40, 615-618 (196).
3)]. This hydrogenation is called partial hydrogenation or selective hydrogenation, and it selectively reduces polyunsaturated fatty acid residues such as linoleic acid, and is accompanied by some changes in iodine value (IV). It is a thing.

However, despite the fact that the solid soaps based on these partially hydrogenated fatty acid salts, especially the mechanically kneaded solid soaps, have good properties such as skin irritation, detergency and foaming property, Frequently, streaky cracks occur during use. The solid soap with such cracks not only loses the original smooth feeling of soap, but also
Various kinds of dirt penetrates, adheres, and remains in the cracked portion, resulting in an unsanitary and unsightly appearance, and as a result, the commercial value thereof is significantly reduced.

In order to prevent such cracking of the solid soap, various methods have hitherto been proposed. For example,
There is an approach from the compounding and prescribing side by adding a dibasic fatty acid, adding an organic polymer compound (carboxyvinyl polymer, hydroxyethyl cellulose, etc.), or adding glycerin, etc. A method of making the distribution amount as uniform as possible has also been proposed.

However, the conventional methods for preventing cracking of soap represented by these cannot be said to have sufficient effects, and conversely, there are many drawbacks particularly in the solution method using additives. Was the reality. In other words, the increase in cost is extremely large, the foaming that is a basic element of soap is obstructed, and when used in relatively hot water such as when bathing, the soap may become dull or melt and collapse. It was a cause of encouragement.

[0006]

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a solid soap which is based on a partially hydrogenated fatty acid salt and is free from cracking.

[0007]

Therefore, as a result of various studies on the relationship between the partially hydrogenated fatty acid salt and cracking, the present inventors have found that partial hydrogenation causes not only the original hydrogenation but also an isomerization reaction such as cis-isomerization. Isomerization of oleic acid to elaidic acid, which is a trans form, occurs, but not only is solid soap containing a large amount of fatty acid salt with advanced isomerization prone to cracking, but also poor solubility in cold water. Found. Then, after further research, it was found that cracking of the solid soap can be effectively prevented if a certain amount of the solid soap based on a partially hydrogenated fatty acid salt of caprylic acid, pelargonic acid, or capric acid is contained. The present invention has been completed.

That is, the present invention relates to a solid soap composition based on a sodium salt of a partially hydrogenated fatty acid, and a salt of one or more fatty acids selected from caprylic acid, pelargonic acid and capric acid. The solid soap composition is characterized by containing 3 to 6% by weight of fatty acid. Caprylic acid used in the present invention,
The salts of pelargonic acid and capric acid can prevent cracking even if they are used alone or as a mixture of two or more kinds. here,
These salts refer to sodium salts, potassium salts, triethanolamine salts and the like, and sodium salts are particularly preferable. The content of these solid soap compositions in the fatty acid conversion is 3 to 6% by weight (hereinafter, simply indicated by "%") of the total amount of the fatty acids in the composition. If this amount is less than 3%, the effect of preventing cracking is small, and if it exceeds 6%, it becomes too soft, and further improvement of the effect cannot be expected, which is not preferable.

The fats and oils as the raw material of the partially hydrogenated sodium salt of fatty acid, which is the base of the bar of the present invention, include
Oils and fats containing a large amount of unsaturated fatty acid residues such as beef tallow, lard, sheep fat, fish oil, palm oil and peanut oil are preferable. In order to make these fats and oils into soaps, the so-called neutral oil saponification method in which the above-mentioned fats and oils raw materials are blended in an appropriate ratio and saponified with an alkaline aqueous solution such as sodium hydroxide and potassium hydroxide to obtain soaps
So-called fatty acid neutralization method in which the above-mentioned fat and oil raw material is first decomposed into fatty acids, and the free fatty acids are pretreated as necessary to neutralize with an alkaline aqueous solution to obtain soap, and from the above fat and oil raw materials, methyl ester is first obtained. Obtain, after pretreatment if necessary,
There is a so-called methyl ester method for obtaining soap by saponifying it with alkali, and any method can be adopted.

Further, the partial hydrogenation can be carried out in any of the above-mentioned raw material oil and fat, free fatty acid or methyl ester. This hydrogenation can be carried out by a conventional method. For example, a known catalyst such as a nickel catalyst, a nickel formate catalyst, a Raney nickel catalyst or a platinum catalyst is used in an amount of 0.001 to 2% by weight with respect to the fatty acid or its derivative, and at room temperature to 23.
At 0 ° C., a hydrogen pressure of normal pressure to 20 kg / cm ² G (gauge pressure) and a time until the ratio of elaidic acid / oleic acid = 5/95 to 70/30 may be appropriately selected.

The solid soap composition of the present invention comprises caprylic acid,
It contains a salt of a fatty acid selected from pelargonic acid and capric acid, and the step of adding these may be appropriately added to the above production method. For example, in the neutral oil saponification method, it is preferable to add after the salting-out step for the above reason, and in the fatty acid neutralization method, the methyl ester method and the like, it is preferable to add it immediately before neutralization or saponification. However, in this neutral oil saponification method, adding after the salting-out step means adding after the saponification reaction, so in some cases pre-neutralized fatty acid salt, that is, fatty acid soap having 8 to 10 carbon atoms is added. Will be done.

In addition to the main components described above, free fatty acids, pigments, fragrances, stabilizers, and other well-known components conventionally used in conventional solid soap compositions may be optionally incorporated into the present solid soap composition.

[0013]

The solid soap composition of the present invention does not crack during use and has good solubility in cold water.

[0014]

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. Example 1 A nickel catalyst was added to beef tallow fatty acid so that the concentration was 0.04% by weight, a hydrogen pressure of 0.5 to ² kg / cm ² G, 170 to 190.
A fatty acid hydrogenated at a temperature of ℃ (oleic acid: elaidic acid in C ₁₈ F ₁ fatty acid = 69: 31) and a coconut oil fatty acid were mixed at a ratio (weight) of 70:30, and the mixture was mixed with a conventional method to obtain 25
% Sodium hydroxide aqueous solution, salted out three times, dried, mixed with a dye, a flavor and a stabilizer, kneaded with stirring, and then extruded and punched to prepare a solid soap (Comparative Control Product A). On the other hand, in preparing solid soap with the same raw materials, the same mixing ratio, and the same manufacturing process as above, Na salts of various fatty acids described below (that is, fatty acid soap) are shown in Table 1 in the step after salting out. Each of the indicated amounts was added in an external ratio. The solid soap sample thus obtained was subjected to a crack model test and a practical long-term hand-washing practical crack test. In addition, the actual measurement results of the fatty acid composition (weight ratio by gas chromatography) of each test sample soap including the comparative control product and the present invention product are also shown. The crack evaluation method is as follows. (1) Crack model test: 1 cm from solid soap sample
A test piece of x1 cm x 5 cm is cut out, immersed in water at 25 ° C for 4 hours, and naturally dried for 1 day, and then the degree of cracking is visually judged. Rating: 0 ・ ・ ・ ・ No cracks are observed 1 ・ ・ ・ ・ Slightly 1-2 cracks 2 ・ ・ ・ ・ ・ ・ Several cracks 3 ・ ・ ・ ・ ・ ・ Deep cracks on the entire surface (2) Practical test for long-term hand-washing cracks The soap bar samples were subjected to normal hand-washing once every morning and evening using tap water (average temperature 12 ° C) outdoors in winter, and the number of days until cracking was examined. Those that did not show cracks even after continuing the test for one month were evaluated as not cracking. The results are shown in Table 1. In Table 1, A is nothing added, B is stamped caprylic acid Na
Is added, C is added with capric acid Na,
D is the addition of a 1: 1 mixture thereof, and E
Is the one to which Na pelargonate is added, and all of B to E are those to which the crack preventing agent of the present invention is added.

[0015]

[Table 1]

As described above, when the total amount of fatty acids having 8 to 10 carbon atoms was 3% or more, neither cracks occurred in the crack model test nor the long-term hand-washing crack practical use test.

Claims (1)

[Claims] 1. A solid soap composition based on a sodium salt of a partially hydrogenated fatty acid, wherein a salt of one or more fatty acids selected from caprylic acid, pelargonic acid and capric acid is added to the total amount of fatty acids. A solid soap composition containing 3 to 6% by weight of the solid soap composition.