JPS6130509A - Dermal external drug - Google Patents

Abstract

PURPOSE:A dermal external drug, containing urea and further a basic amino acid salt together, capable of improving the stability of the urea in the presence of water with time, and useful for cosmetics or medicines, e.g. a remedy for xeroderma. CONSTITUTION:A dermal external drug, obtained by incorporating a basic amino acid salt, e.g. hydrochloride, hydrobromide, acetate, pyrrolidonecarboxylate or urocanate of a basic amino acid, e.g. histidine, lysine, ornithine or arginine, etc. in an amount of 1/10-3 times that of urea in a dermal external drug containing 0.1-2wt% urea having wetting effect, cell activating effect and wound curing effect, etc., and capable of suppressing the decomposition of the urea in the presence of water and preventing the deterioration of the dermal external drug and pH increase, and having improved stability with time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a skin preparation for external use that improves the oral stability of urea by incorporating a basic amino acid salt with urea.

[Prior Art] When urea is incorporated into external skin preparations, it is expected to have moisturizing effects, cell activation effects, wound healing effects, and the like. However, because it gradually decomposes in the presence of water and generates ammonia and carbon dioxide gas, there have been few opportunities to incorporate it into cosmetics, although it is expected to have various effects.

There have been several reports of efforts to stably incorporate urea into external preparations for the skin, but none of them have yielded satisfactory results).

For example, a report on combining lactic acid with urea < usp3
No. 666863) can reduce the initial pIl but is not effective in improving oral stability.

[Problems to be Solved by the Invention] In view of the above circumstances, the present inventors conducted intensive studies to improve the oral stability of urea in the coexistence of water, and as a result, they came up with the present invention.

[Means for Solving the Problems] That is, the present invention provides an external skin preparation characterized by blending urea and a basic amino acid salt.

The configuration of the present invention will be explained in detail below.

As the urea used in the present invention, any commercially available urea may be used.

The blending amount of urea is in the range of 0.1 to 20% by weight (hereinafter simply referred to as %); below that level, the above-mentioned effect of urea on the skin is small, and above that level, according to the Pharmaceutical Affairs Law.
This is outside the scope of external skin preparations and is subject to regulations.

The basic amino acids that make up the basic amino acid salts added for the purpose of improving stability include histidine, lysine, ornithine, and arginine, and the salts include hydrochloride, hydrobromide, acetate, and pyrrolidone. Organic acid salts such as carboxylates and urocanates can also be used.

The amount of basic amino acid salt added is 1/1 by weight of urea.
It is desirable that it is 0 times or more and 3 times or less. However, adding too much basic amino acid salt may cause the basic amino acid salt itself to change in quality, causing discoloration and
Care must be taken as it may cause off-odor, etc.

The skin external preparation bases that can contain urea and basic amino acid salts include the usual skin external preparation bases, such as solubilized systems, emulsified systems, powder dispersion systems, water-based two-layer cosmetics, and water-oil based cosmetics. Any base such as powder type 3N cosmetics can be used, and the application is basic cosmetics such as lotion, milky lotion, cream, pack, etc., makeup cosmetics such as emulsified lipstick, foundation, etc.
In addition to cosmetics such as hair cosmetics such as shampoos, conditioners, and hair tonics, there is a wide range of pharmaceutical products such as drugs for treating xeroderma. be done. The concentration of the urea aqueous solution is arbitrary. Further, as described above, even if the urea aqueous solution is in an emulsified form with an oil phase, there is no problem and the effects of the present invention can be exhibited. However, if the base itself is strongly basic, the basic substance may promote decomposition more than the stability maintaining effect of the basic amino acid salt, which is not preferable.

The skin external preparation of the present invention may contain moisturizers, thickeners, preservatives, emulsifiers, antioxidants, sequestrants, ultraviolet absorbers, powders, medicinal agents, etc., as necessary, to the extent that the effects of the present invention are not impaired. Ingredients, colorants, fragrances, etc. can be added.

According to the present invention, when urea and a basic amino acid salt are simultaneously incorporated into a skin preparation for external use, the oral stability of urea is significantly improved compared to when the basic amino acid salt is not used in combination. That is, (a) ammonia is not generated due to decomposition of urea, and the skin external preparation does not deteriorate due to ammonia odor. (b) In a system in which a basic amino acid salt is not used in combination, the pH value rises rapidly, but when used in combination, effects such as almost no pH rise are observed.

[Examples and Effects of the Invention] Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Examples 1-2, Comparative Examples 1-3 (blank below) Base = lotion ethanol 13.0%
1.3-Butylene glycol 10. O
P, O, E, (50) Oleyl ether 0
．． 8 Add preservatives, appropriate amounts of fragrances, appropriate amounts of each of the above base components, urea, and additives, and then add purified water in an amount to make the total amount 100%.

is a sample containing additives other than basic amino acid salt.

It is desirable that the pH change, ammonia odor, and odor change are both small, and that the quantitative value is high, and the examples satisfy all of these.

Example 3 Night cream A, Cefnol 4.0% Vaseline 7.0 Squalane 21.0 Monoglyceryl stearate 2.2 Ester P, 0. E, (20) Sorbitan 2.
8 Monostearate Isoprobyl myristate 6.0 Ethylvarachen 0.3 Fragrance
0.2B, glycerin
10.0 Propylene glycol
5.0 Urea 10
．． OL-Arginine Hydrochloride 3.0 Purified Water 70% each of the raw material for the oil phase belonging to A and the raw material for the aqueous phase belonging to B, with the total amount being 100.
After heating to ℃ and completely melting, the oil phase is mixed into the water phase and emulsified using an emulsifying machine. Finish the emulsion with a heat exchanger 3
A night cream was obtained by cooling to 0°C.

The formulation described in Example 3, in which only mustard monoarginine hydrochloride was removed, was prepared at the same time as Example 3, and after being stored at 40°C for 2 months, urea was quantified.
In Example 3, 98-99% remained, whereas L-
When arginine hydrochloride was removed, the amount decreased to 87-89%.

Example 4 Foundation A, Cefnol 3.5% odor lanolin 4.0 Bojoba oil
5.0 Vaseline
2.0 squalane
6.0 Monoglyceryl stearate 2
．． 5 esters P, O, E (60) Hydrogenated castor oil 1.
5P, 0. E (25) Cetyl ether 1.
0 Propylparaben 0.3 Fragrance
0.2B, glycerin 3.0 Propylene glycol
8.0 blended powder
12.0 Urea 3.
OL-ornithine hydrochloride 2.0 purified water
A foundation was obtained according to Example 3, with the total amount being 100.

A formulation in which only L-ornithine hydrochloride was removed from the formulation described in Example 4 was prepared at the same time as Example 4, and after being stored at 40°C for 2 months, urea was quantified. While 98% remained, in the case where L-ornithine hydrochloride was removed, the amount was reduced to 85-90%.

Example 5 Emollient Essence Glycerin 10.0% Propylene Glycol 5.0 Ethyl Alcohol 5. OP, 0. E,
(50) Oleyl ether 0.5 carboxyvinyl polymer 1.0 urea
1.0 lysine acetate
1.5 arginine acetate
1.5 fragrance
Appropriate amount of purified water, total 100
An emollient essence was obtained by uniformly mixing and dissolving the above components in the following amounts.

A formulation in which only the basic amino acid salt was removed from the formulation described in Example 5 was prepared at the same time as Example 5, and the mixture was heated at 40°C for 2 hours.
After being stored for several months, urea was quantified and found that 96-98% remained in Example 5, while it decreased to 83-85% in the product from which the basic amino acid salt was removed.

Claims (1)

[Claims] An external skin preparation characterized by containing urea and a basic amino acid salt.