JPH04282306A - Cosmetic containing carboxymethylated polysaccharide salt - Google Patents

Abstract

PURPOSE:To provide a new cosmetic containing water-soluble alkali metal salt of a polycarboxymethyl-N-acetylglucosamine and having excellent moisture- retainability and phylactic effect to bacteria, etc. CONSTITUTION:The objective new cosmetic contains one or more kinds of alkali metal salts of a polycarboxymethyl-N-acetylglucosamine produced by carboxymethylating a chitin (i.e., poly-N--acetylglucosamine) in an alkaline solution and precipitating in alkaline state. The compound, especially sodium salt, is a safe substance utilizable as food, etc. The cosmetic compounded with the compound has high affinity to the human epidermic tissue and is useful for preventing the aging of dermatic tissue caused by the increase in the age.

Description

[Detailed description of the invention]

0001

FIELD OF THE INVENTION The present invention relates to a new cosmetic containing an alkali metal salt of water-soluble polycarboxymethyl-N-acetylglucosamine.

0002

BACKGROUND OF THE INVENTION Conventionally, materials with high moisturizing properties such as chitin, hyaluronic acid, and chondroitin sulfate have been used in cosmetics as compounds containing N-acetyl glucoside. Further, an example using a carboxymethylated chitin similar to the present invention is disclosed in JP-A-59-106409.

0003

[Problem to be solved by the invention] However, (1)
Chitin is hardly soluble in water, so its applications are limited. (2) Hyaluronic acid and chondroitin sulfate are limited in terms of raw materials, and their manufacturing methods are complicated and extremely expensive. It has aspects that make it difficult to use in general cosmetics. Also,
The example using a carboxymethyl compound disclosed in JP-A-59-106409 is in the form of an acid with a free carboxyl group. Carboxymethyl chitin itself, which has such a chemical structure, has different solubility depending on its molecular weight, and those with high molecular weight have extremely low solubility, which is inconvenient when incorporated into cosmetics, while those with low molecular weight have Although it has high solubility, it has a drawback of low moisturizing effect.

[0004] In order to solve such drawbacks, the present inventors
As a result of extensive research, we have found that an alkali metal salt of polycarboxymethyl-N-acetylglucosamine (hereinafter often referred to as "the present compound") consisting of a specific high molecular weight is extremely effective as a component in cosmetics. Based on this knowledge, we have completed the present invention.

[0005]

[Means for Solving the Problems] That is, the present invention is a cosmetic composition containing one or more alkali metal salts of polycarboxymethyl-N-acetylglucosamine. The present invention will be further explained in detail below. Chitin is a raw material for the alkali metal salt of polycarboxymethyl-N-acetylglucosamine. Chitin exists in large quantities in nature, and is currently the second largest natural polymer on earth after cellulose.As it is present in the shells of shrimp and crabs, chitin is produced in large quantities as a by-product from shrimp and crab processing factories in Japan. It is produced in Furthermore, chitin is a polysaccharide represented by β-poly-N-acetyl-D-glucosamine, but due to strong hydrogen bonds between molecules, it has the property of being almost insoluble in water and other solvents.

Polycarboxymethyl used in the present invention
The alkali metal salt of N-acetylglucosamine is a compound obtained by carboxymethylating chitin, that is, poly-N-acetylglucosamine in an alkaline solution, and then precipitating on the alkaline side. There are no particular restrictions on how to obtain it. To give an example of a manufacturing method, when poly-N-acetylglucosamine is dissolved in an alkaline solution, dissolving it for a long time or dissolving it at high temperatures will cause the molecular weight to decrease, deacetylation, and by-products to be produced. - By freezing an acetylglucosamine alkaline solution mixture at around -10°C and then thawing it at 0 to 5°C, a poly-N-acetylglucosamine alkaline solution can be prepared without a decrease in molecular weight or by-products of deacetylation. is obtained.

[0007] As the alkaline solution used in this method, aqueous solutions of sodium hydroxide, potassium hydroxide, and other alkali metal salts are generally used. The amount added is 1 to 10% as a metal salt to poly-N-acetylglucosamine.
It is twice equivalent, preferably 5 to 8 times equivalent. Next, an alkali metal salt solution of polycarboxymethyl-N-acetylglucosamine is obtained by reacting 1 to 8 times equivalent, preferably 3 to 5 times equivalent, of monochloroacetic acid as a carboxylmethylating agent. Add an acid, such as hydrochloric acid, to this to reach an isoelectric point of PH9.
When precipitated on the above alkali side, a solid alkali metal salt is obtained.

[0008] Examples of the alkali metal salts include sodium salts, potassium salts, lithium salts, etc.
There are no particular restrictions. This compound has high solubility in water, so it is extremely useful when incorporated into cosmetics. The structural formula of the sodium salt of this compound is shown in Chemical Formula 1. In this formula, n is 200 to 4000.

[0009]

[Chemical formula 1]

The structural formula of the potassium salt of this compound is
Similarly, in the structural formula of the lithium salt, Na and Li are substituted in chemical formula 1.

Polycarboxymethyl-N used in the present invention
- The weight ratio of acetylglucosamine alkali metal salt to cosmetics is 0.01 to 5 to 100 parts of cosmetics.
It is. Depending on the form of the cosmetic, it is 0.01 to 1.0, preferably 0.2 to 1.0 in the case of liquids such as lotions and hair styling products.
It is 0. For creams and gels, it is 0.5 to 5, preferably 1 to 3.

Regarding safety, carboxymethylated natural products generally have low toxicity, and the sodium salt of carboxymethylcellulose is also used in foods. The alkali metal salt of polycarboxymethyl-N-acetylglucosamine used in the present invention has been subjected to various safety tests and has been found to have oral acute toxicity, primary skin irritation, continuous skin irritation, skin sensitization, phototoxicity, photosensitization, ocular mucosal irritation,
No abnormalities were observed in any items such as mutagenicity and human patch tests.

[0013] The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to the following Examples. In Examples 1 to 3, polycarboxymethyl-
An example of the formulation of N-acetylglucosamine sodium salt in cosmetics is shown.

Example 1 Emulsion <Ingredients>

<Blend amount> Liquid paraffin

14.0 (wt%) cetanol

2.0 white beeswax

0.3 Purified lanolin

1.0 Polyethylene glycol monostearate 4.0
polysorbate 80
6.0
span 80

4.0 Methylparaben

0.1 purified water

65.6 Fragrance

0.5 polycarboxymethyl-N-
Acetylglucosamine Na salt 2.5

0015
] Example 2 Lotion <Ingredients>

<Containing amount> Emulsion

0.5 (wt%) glycerin

5.0 ethanol

15.0 Methylparaben
0.1 purified water

73.9 Collagen
5.0 Polycarboxymethyl-N-acetylglucosamine Na salt
0.5

Example 3 Hair tonic
<Ingredients>
<
Ingredients > Olive oil

5.0 (wt%) isopropyl myristate

2.0isopropylmethylphenol
0.05
Polyoxyethylene nonylphenyl ether
0.5 ethanol

55.0 Glycerin

5.0 Methylparaben

0.2 Purified water

31.75 Polycarboxymethyl-N-acetylglucosamine Na salt 0
．． 5

Example 4 The formulations of Examples 1 to 3 were distributed to 5 men and 15 women between the ages of 20 and 45, and a questionnaire was collected regarding the feeling of use. A comparison was made with each emulsion, lotion, and hair tonic that each person currently uses. The results are shown in Table 1.

[0018]

[Table 1]

Example 5 Moisturizing property A test was conducted on the moisturizing property of polycarboxymethyl-N-acetylglucosamine sodium salt. 0.5 of the test compound
% aqueous solution, soak a certain amount onto the filter paper, and keep it at a temperature of 2.
The weight was measured while keeping the temperature at 5℃ and changing the outside humidity.
Its moisturizing power was evaluated. The results are shown in Table 2. For the numerical values in Table 2, the weight of the specimen immediately after the aqueous solution of the specimen was soaked into the filter paper (1 minute later, indicated as 0 hr in the table) was taken as 100, and the weight change over time was described. The results revealed that there is almost no difference in moisturizing properties from sodium hyaluronate, which is said to be a highly moisturizing agent.

[0020]

[Table 2]

Example 6 Antibacterial properties Polycarboxymethyl-N-acetylglucosamine alkali metal salt was added to an ordinary agar medium, sterilized, and left in the laboratory for a certain period of time. After being left in an incubator at 40°C for 12 hours, the number of colonies was counted. Examined. The results are shown in Table 3. The composition of the medium used is shown below.

Medium composition Glucose 0.5 Yeast extract 0.5 Polypeptone
0.5 salt
0.5 agar
1.5 Adjust to 100 with purified water.

[0023]

[Table 3]

[0024]

[Effect of the invention] Polycarboxymethyl used in the present invention
The alkali metal salt of N-acetylglucosamine is extremely soluble in water, and its aqueous solution has excellent moisturizing properties and protection against infections such as bacteria, so cosmetics containing it have an affinity with the human body's epidermal tissue. It is useful for preventing aging of skin tissues due to aging.

Claims (1)

[Claims] 1. A cosmetic comprising one or more alkali metal salts of polycarboxymethyl-N-acetylglucosamine.