JPH02155996A - Lowly irritant solid detergent - Google Patents

Abstract

PURPOSE:To obtain the title detergent which is very smooth to the touch during or after use and serves as a detergent suitable for those having a delicate skin by incorporating a specified amount of a betaine type ampholytic surface active agent into a soap base. CONSTITUTION:100pts.wt. soap base is mixed with 1-70pts.wt. betaine type ampholytic surface active agent comprising a compound of, e.g. formula I or II (wherein R1 and R2 are each 3-29C alkyl or alkenyl; A is CH2SO3<->; x is 2 to 4; y is 0 to 3).

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hypoallergenic solid detergent, and more particularly to a hypoallergenic solid detergent prepared by blending a specific surfactant into a soap base.

[Conventional technology]

Conventionally, hypoallergenic solid detergents include soap-based detergents, such as superfat soaps made by adding an excess of saturated fatty acids after neutralizing or drying the soap, and triethanolamine salts of fatty acids. Salts with low pH are known. In addition, synthetic surfactants are used in combination with soap, such as near-neutral anionic surfactants such as sodium lauryl sulfate, and weakly acidic surfactants such as sodium N-acylglutamate. What has been done is known.

These hypoallergenic solid detergents are discussed in detail in, for example, ``Recent Hypoallergenic Soaps'' (Fragrance Journal, Vol. 47, p. 47, 1981).

[Problem to be solved by the invention]

However, these conventional hypoallergenic solid detergents are still not fully satisfactory in terms of hypoallergenicity. In particular, in the case of superfatted soaps, the pH is still high, although problems such as free alkali are alleviated, and similarly, in the case of triethanolamine salts of fatty acids, the pH is lower than that of alkali metal salts of fatty acids, but still has a pH of 9. before and after,
Furthermore, anionic surfactants such as sodium lauryl sulfate have extremely strong cleaning power, so there is a risk that the sebum film will be washed away excessively.

For this reason, these conventional hypoallergenic solid detergents may feel slimy during use, or leave a sticky or dry feeling after drying, but do not provide the smooth feel desired as a hypoallergenic detergent. The problem was that it was difficult to obtain.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional circumstances, an object of the present invention is to provide an improved, hypoallergenic solid detergent that can provide a very smooth feel during or after use.

[Means to solve the problem]

As a result of intensive studies to achieve the above object, the present inventors have found that by blending a specific amount of a specific surfactant into a soap base, they can maintain the excellent foaming properties inherent in detergents and the In addition to its cleansing properties, it does not have the rancidity seen with conventional fat soaps or the strength problems seen with sodium N-acylglutamate, which means it has good quality stability and formability. In addition to obtaining a solid cleaning agent,
The present invention was completed based on the knowledge that this cleaning agent has improved hypoallergenicity compared to conventional cleaning agents, and therefore provides a very smooth feel during and after use. reached.

That is, the present invention relates to a hypoallergenic solid detergent characterized by blending 1 to 70 parts by weight of a betaine amphoteric surfactant with respect to 100 parts by weight of a soap base.

[Structure and operation of the invention]

The soap base used in the present invention includes conventional soap bases such as animal and vegetable oils such as beef tallow, lard, coconut oil, palm oil, palm kernel oil, soybean oil, mixed fatty acids and simple fatty acids thereof. Obtained by resaponification-2 neutralization of various oils and fats or fatty acids known as raw material components of agents by conventional methods.
Soaps made of various salts such as alkali metal salts, ammonium salts, and lower alkanolamine salts are widely included. Among these, soaps made of alkali metal salts such as sodium salts and potassium salts are particularly preferred.

In the present invention, the betaine-based amphoteric surfactant to be blended into the stone laa base as described above is an amide betaine-based amphoteric surfactant represented by the following general formula (11), - represented by the general formula (2) Amidosulfopetaine type amphoteric surfactant, betaine type amphoteric surfactant represented by general formula (3), -t
Included are a sulfobetaine type amphoteric surfactant represented by formula (4), an imidazolinium betaine type amphoteric surfactant represented by general formula (5), and the like. Among these,
The former two amidobetaine type amphoteric surfactants and amidosulfopetaine type amphoteric surfactants are particularly preferred.

R3N'''' CHz C00- (CHz)y CR3 R4N' (CR2)XS 0y (CHz)y CR3 In each of the above formulas, R,, R,, R6 have 3 to 2 carbon atoms.
9 alkyl group or alkenyl group, R3 and R4 are alkyl group or alkenyl group having 4 to 30 carbon atoms, X is 2 to
4 is an integer, y is an integer from 0 to 3, and 2 is an integer from 1 to 2.

In the present invention, the amount of the betaine amphoteric surfactant is 1 to 100 parts by weight of the soap base (dry soap).
It is 70 parts by weight, particularly preferably 5 to 50 parts by weight. If this amount is less than 1 part by weight, the hypoallergenic effect cannot be obtained,
Moreover, if it exceeds 70 parts by weight, problems will arise in formability.

The hypoallergenic solid detergent of the present invention is produced by uniformly mixing the above betaine-based amphoteric surfactant in the above ratio with a soap base,
This can be produced by extrusion molding using conventional methods. At that time, the timing of adding the surfactant is not particularly limited, and it may be added to the neat soap after neutralization, or may be added to the soap chips after drying.

In the present invention, in order to uniformly mix the betaine-based amphoteric surfactant into the soap base, various other surfactants may be appropriately used in combination as necessary. Other surfactants include, for example, Nishibu Genus: "Surfactant Handbook"
(published by Sangyo Tosho Co., Ltd.) and edited by Soft Giken Publishing Department:
Elucidation of the functional effects of new surfactants and development of applied products.
Various well-known surfactants such as those described in "Practical Comprehensive Technical Data Collection" (Management Development Center Publishing Department) are widely included.

In addition, the hypoallergenic solid detergent of the present invention can contain various polymeric substances in order to improve its formability, and may further contain chelating agents such as EDTA, humectants such as hyaluronic acid, and fragrances. Various additives such as dyes and the like added to ordinary soaps may also be included.

〔Effect of the invention〕

As described above, in the present invention, by incorporating a specific amount of betaine-based amphoteric surfactant into the soap base, it not only satisfies basic properties such as foaming properties, appropriate cleansing properties, and formability. , you can get an unconventional solid cleaning agent with improved hypoallergenicity, and this cleaning agent can give you a very smooth feel during and after use, making it suitable for people with sensitive skin, people with allergies, etc. It is especially suitable for strong people and people whose skin has become weak due to aging.

〔Example〕

EXAMPLES Below, the present invention will be explained in more detail by describing examples.

Example A 28% by weight aqueous sodium hydroxide solution was added to a mixture of beef tallow fatty acid and coconut oil fatty acid at a weight ratio of 8:20, and the mixture was stirred and mixed in a tabletop kneader with a capacity of 51 [manufactured by Irie Shokai ■]. , make it into a neat soap with a water content of about 30% by weight,
After adding the betaine-based amphoteric surfactant and other additive components shown in Table 1 below in the proportions shown in the same table,
It was dried until the moisture content was about 14% by weight.

Next, apply this soap composition to three rolls [manufactured by Ashizawa ■;
Roll rotation speed 2Orpm, 48rpa+, 10
107 rpm to form flakes, add titanium dioxide and fragrance in the proportions shown in Table 1, stir in a kneader for 10 minutes, and then press the screw of a laboratory soap extruder (manufactured by Sago Iron Works). After kneading one portion three times, the mixture was extruded from the cone portion and stamped to obtain hypoallergenic solid detergents of samples at to 7 according to the present invention.

Comparative Example A solid detergent with a sample weight of 8 to 1O was prepared in exactly the same manner as in the example except that the conventional compounding agents shown in Table 1 were used in the proportions shown in the same table instead of the betaine-based amphoteric surfactant. I got it.

The numbers in parentheses in the conventional formulations shown in Table 1 are the number of moles of ethylene oxide added. Further, the blending ratio of each component shown in the same table is the number of parts by weight based on 100 parts by weight of the soap base (dry soap).

In order to evaluate the performance of each of the solid cleaning agents of the above Examples and Comparative Examples, usability tests were conducted in the following manner. The results were as shown in Table 1 below.

<Usability test> Using each solid detergent as a sample, a panel of 10 people (5 men and 5 men in total) was used to clean and rinse either the left or right arm with the sample and the other arm with water using a towel. After wiping it off, the usability of the left and right sides (smoothness during and after use) was judged as shown below.

◎... Very good usability (8-10 out of 10 people answered that the usability of the sample side was good compared to the control.) ○... Good usability (6-7 out of 10 people answered that the usability of the sample side was better than the control) Compared to the control, the sample side answered that the usability was good.) △... Usability was fair (4 to 5 people out of 10 answered that the sample side usability was good compared to the control.) ×・...Poor usability (0 to 3 out of 10 people answered that the usability of the sample side was better than the control.) The above control refers to the use of the betaine of the present invention in the production of the solid detergent described above. This is a cosmetic soap with a normal composition that does not contain any amphoteric surfactant or the compounding agents of the comparative example.

As is clear from Table 1 above, the solid detergent containing a specific amount of betaine-based amphoteric surfactant in a soap base according to the present invention has a higher
It can be seen that it provides a very smooth feel during and after use.

Furthermore, in the above usability test, it was simultaneously found that each solid detergent of the present invention satisfactorily satisfies all of the characteristics of foaming properties, appropriate detergency properties, and formability. did.

Patent applicant: NOF Corporation

Claims (1)

[Claims] (1) A hypoallergenic solid detergent characterized by blending 1 to 70 parts by weight of a betaine amphoteric surfactant to 100 parts by weight of a soap base.