JP2005119995A - Method for increasing area of horny layer cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for flattening and increasing the area of honey layer cells by a chemical means such as the administration of an external preparation for the skin to improve the barrier function of the skin. <P>SOLUTION: This kit for the external preparation for the skin comprises (1) the first agent containing an α-hydroxycarboxylic acid and (2) the second agent containing a base for neutralizing the α-hydroxycarboxylic acid as constituents. The kit is characterized by treating the skin with the first agent for 1 to 20 min and then immediately neutralizing the first agent with the second agent. The preferable example of the α-hydroxycarboxylic acid is a glycolic acid. The content of the α-hydroxycarboxylic acid is especially preferably 1 to 60 mass %. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention exists in the outermost surface of the skin in a person whose area of horny layer cells on the outermost surface of the skin is smaller than the average area, in other words, in a person with a low barrier function with less flatness of the horny layer cells. The present invention relates to a method for increasing the area of stratum corneum cells and a skin external preparation kit therefor.

  The stratum corneum cells are present on the outermost part of the skin and have a barrier function such as stimulation protection or prevention of contact between a chemical substance and a living body. The stratum corneum cells are generally larger in area, flattened and matured better, and have better barrier function. Smaller and thicker areas have weaker and lesser barrier functions. Are known. For this reason, the sensitivity of the skin and the state of the skin can be distinguished by the area of the stratum corneum cells. (For example, refer to Patent Document 1, Patent Document 2, Patent Document 3, and Patent Document 4) In such a stratum corneum cell, when the skin condition becomes worse and the area of the stratum corneum cell becomes smaller, The only way to increase the area is to administer moisturizers etc. externally and wait for the stratum corneum cells to mature, large in area, and flattened while complementing the decrease in skin barrier function. It was. In other words, it was developed despite the desirability of developing means for improving the skin barrier function by increasing and flattening the area of stratum corneum cells by chemical means such as administration of an external preparation for skin. The current situation was not.

  On the other hand, although α-hydroxycarboxylic acid is a cosmetic raw material, it has a keratin exfoliating action (see, for example, Patent Document 5), a skin irritation action (for example, see Patent Document 6), and a chemical peeling action (for example, Is known), but its effect on the area of stratum corneum cells is not known at all.

  In addition, as an external preparation for skin that affects the stratum corneum cells, various active ingredients have been known to have an effect of reducing the variation in the area of the stratum corneum cells (for example, Patent Document 8, Patent Document). 9, see Patent Document 10), nothing that increases the area and makes it flat is not known at all.

JP 2003-38449 A JP 2001-13138 A Japanese Patent Laid-Open No. 11-128175 JP 09-38045 A JP 2002-234845 A Japanese National Patent Publication No. 11-502504 JP 2000-86036 A JP 09-169616 A JP 09-81133 A Japanese Patent Laid-Open No. 05-221844

  The present invention has been made under such circumstances, and means for improving the skin barrier function by increasing and flattening the area of stratum corneum cells by chemical means such as administration of an external preparation for skin. It is an issue to provide.

In view of such circumstances, the present inventors have sought a means for improving the skin barrier function by increasing and flattening the area of stratum corneum cells by chemical means such as administration of an external preparation for skin. As a result of intensive research efforts, 1) a first agent containing α-hydroxycarboxylic acid and 2) a second agent containing a base for neutralizing the α-hydroxycarboxylic acid By using a skin external preparation kit characterized in that, after treating with the first agent for 1 to 20 minutes, immediately neutralizing with the second agent, the area of the horny layer cells is reduced. The inventors have found that the skin barrier function can be improved by increasing and flattening, and the present invention has been completed. That is, this invention relates to the technique shown below.
<1> In the person whose area of the horny layer cells existing on the outermost surface of the skin is smaller than the average area, in other words, in the person having a small barrier function and a low barrier function, the angle existing on the outermost surface of the skin A skin external preparation kit for increasing the area of layer cells, comprising 1) a first agent containing α-hydroxycarboxylic acid, and 2) a base for neutralizing the α-hydroxycarboxylic acid. A skin external preparation kit characterized by comprising a second agent containing as a component.
<2> The kit for external preparation for skin according to <1>, wherein the α-hydroxycarboxylic acid in the first part of the kit for external preparation for skin is glycolic acid.
<3> The skin external application according to <1> or <2>, wherein the content of α-hydroxycarboxylic acid in the first part of the kit for external preparation for skin is 1 to 60% by mass. Agent kit.
<4> In the second agent containing a base for neutralizing the α-hydroxycarboxylic acid, the base is an alkali metal or alkaline earth metal carbonate or bicarbonate, <1>-<3> The skin external preparation kit according to any one of the above.
<5> The skin according to any one of <1> to <4>, wherein the base in the second agent containing a base for neutralizing the α-hydroxycarboxylic acid is sodium carbonate. External preparation kit.
<6> The second agent containing a base for neutralizing the α-hydroxycarboxylic acid is to be administered 1 to 20 minutes after the administration of the first agent, <1 >-<5> The skin external preparation kit according to any one of the above.
<7> According to the following steps, in a person whose area of the horny layer cells existing on the outermost surface of the skin is smaller than the average area, in other words, the flatness of the horny layer cells The process of increasing the area of stratum corneum cells present on the outermost surface of the skin in a person with few barrier functions.
(1) A step of collecting horny layer cells from the face and measuring the area (2) A step of comparing the area of the horny layer cells with an average horny layer cell area (3) A horny layer cell existing on the outermost surface of the skin When the area of is smaller than the average area, the step of administering the first agent containing α-hydroxycarboxylic acid (4) 1-20 minutes after the administration of the first agent, the α-hydroxycarboxylic acid Step of administering second agent containing base for neutralizing acid (5) Step of wiping the skin with a topical skin preparation for wiping <8> To improve the ability to prevent irritation from outside the skin The process of increasing the area of the stratum corneum cells existing on the outermost surface of the skin in the person according to <7>, wherein the area of the stratum corneum cells existing on the outermost surface of the skin is smaller than an average area.

  According to the present invention, it is possible to provide means for improving the skin barrier function by increasing and flattening the area of stratum corneum cells by chemical means such as administration of an external preparation for skin.

<1> The first agent that is an essential component of the kit for external preparation of the present invention The external preparation kit of the present invention is a person whose area of horny layer cells existing on the outermost surface of the skin is smaller than the average area. In other words, a skin external preparation kit for increasing the area of the horny layer cells existing on the outermost surface of the skin in a person having a low barrier function and a low degree of flatness of the horny layer cell, comprising α-hydroxycarboxylic acid It contains the 1st agent as an essential component, It is characterized by the above-mentioned. α-Hydroxycarboxylic acid is a general term for carboxylic acids having both a hydroxyl group and a carboxyl group in which a hydroxyl group is also bonded to a carbon atom to which a carboxyl group is bonded. For example, lactic acid, glycolic acid, apple An acid etc. can be illustrated suitably. A part of such a component may form a salt with a base. Examples of the salt include alkali metal salts such as sodium salt and potassium salt, alkaline earth metal salts such as calcium and magnesium, organic amine salts such as ammonium salt, triethanolamine salt and triethylamine salt, lysine salt, arginine salt and the like. Preferred examples include basic amino acid salts of Moreover, the said alpha-hydroxycarboxylic acid can also contain a seed | species uniquely, and can also be contained in combination of 2 or more type. The preferable content of the α-hydroxy acid in the first agent of the kit for external skin preparation of the present invention is a form containing 1 to 60% by mass of free carboxylic acid, more preferably 20 to 55% by mass. A particularly preferred form is a form containing 20 to 55% by mass, more preferably 40 to 55% by mass of glycolic acid. In the first agent, in addition to the α-hydroxycarboxylic acid, an optional component usually used in a skin external preparation can be contained. Such optional ingredients include, for example, macadamia nut oil, avocado oil, corn oil, olive oil, rapeseed oil, sesame oil, castor oil, safflower oil, cottonseed oil, jojoba oil, coconut oil, palm oil, liquid lanolin, hydrogenated coconut oil Oils such as hardened oil, mole, hardened castor oil, beeswax, candelilla wax, carnauba wax, ibotarou, lanolin, reduced lanolin, hard lanolin, jojoba wax, waxes, liquid paraffin, squalane, pristane, ozokerite, paraffin, ceresin, petrolatum , Hydrocarbons such as microcrystalline wax, higher fatty acids such as oleic acid, isostearic acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, undecylenic acid, cetyl alcohol, stearyl alcohol, isostearyl Alcohol, behenyl alcohol, octyldodecanol, higher alcohol such as myristyl alcohol, cetostearyl alcohol, cetyl isooctanoate, isopropyl myristate, hexyldecyl isostearate, diisopropyl adipate, di-2-ethylhexyl sebacate, cetyl lactate, malic acid Diisostearyl, di-2-ethylhexanoic acid ethylene glycol, dicaprate neopentyl glycol, di-2-heptylundecanoic acid glycerin, tri-2-ethylhexanoic acid glycerin, tri-2-ethylhexanoic acid trimethylolpropane, tri Synthetic ester oils such as trimethylolpropane isostearate and pentane erythritol tetra-2-ethylhexanoate, dimethylpolysiloxane, methylphenylpoly Loxane, linear polysiloxane such as diphenylpolysiloxane, cyclic polysiloxane such as octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexanesiloxane, amino-modified polysiloxane, polyether-modified polysiloxane, alkyl-modified polysiloxane, Oil agents such as silicone oil such as modified polysiloxane such as fluorine-modified polysiloxane, anionic surfactants such as fatty acid soap (sodium laurate, sodium palmitate, etc.), potassium lauryl sulfate, triethanolamine ether of alkyl sulfate, chloride Cationic surfactants such as stearyltrimethylammonium, benzalkonium chloride, laurylamine oxide, imidazoline-based amphoteric surfactants (2-cocoyl-2-imida Zolinium hydroxide-1-carboxyethyloxy disodium salt, etc.), betaine surfactants (alkyl betaine, amide betaine, sulfobetaine, etc.), amphoteric surfactants such as acylmethyltaurine, sorbitan fatty acid esters (sorbitan) Monostearate, sorbitan sesquioleate, etc.), glycerin fatty acids (glyceryl monostearate, etc.), propylene glycol fatty acid esters (propylene glycol monostearate, etc.), hardened castor oil derivatives, glycerin alkyl ethers, POE sorbitan fatty acid esters (POE sorbitan monooleate, polyoxyethylene sorbitan monostearate, etc.), POE sorbite fatty acid esters (POE-sorbitol monolaurate, etc.), POE glycerin fatty acid ester Tells (POE-glycerol monoisostearate, etc.), POE fatty acid esters (polyethylene glycol monooleate, POE distearate, etc.), POE alkyl ethers (POE2-octyldodecyl ether, etc.), POE alkyl phenyl ethers (POE nonylphenyl) Ethers, etc.), Pluronic types, POE / POP alkyl ethers (POE / POP2-decyltetradecyl ether, etc.), Tetronics, POE castor oil / hardened castor oil derivatives (POE castor oil, POE hardened castor oil, etc.), Nonionic surfactants such as sucrose fatty acid ester and alkyl glucoside, polyethylene glycol, glycerin, 1,3-butylene glycol, erythritol, sorbitol, xylitol, maltitol, propylene Recall, dipropylene glycol, diglycerin, isoprene glycol, 1,2-pentanediol, 1,2-hexylene glycol, polyhydric alcohols such as 1,2-octanediol, sodium pyrrolidonecarboxylate, lactic acid, sodium lactate, etc. Moisturizing ingredients, guar gum, quince seed, carrageenan, galactan, gum arabic, pectin, mannan, starch, xanthan gum, curdlan, methylcellulose, hydroxyethylcellulose, carboxymethylcellulose, methylhydroxypropylcellulose, chondroitin sulfate, dermatan sulfate, glycogen, heparan Sulfuric acid, hyaluronic acid, sodium hyaluronate, tragacanth gum, keratan sulfate, chondroitin, mucoitin sulfate, hydroxyethyl guar gum, potassium Ruboxymethyl guar gum, dextran, keratosulfuric acid, locust bean gum, succinoglucan, caronic acid, chitin, chitosan, carboxymethylchitin, agar, polyvinyl alcohol, polyvinylpyrrolidone, carboxyvinyl polymer, sodium polyacrylate, polyethylene glycol, bentonite Thickeners such as mica, talc, kaolin, synthetic mica, calcium carbonate, magnesium carbonate, silicic anhydride (silica), aluminum oxide, barium sulfate, etc. May be treated, bengara, yellow iron oxide, black iron oxide, cobalt oxide, ultramarine, bitumen, titanium oxide, zinc oxide inorganic pigments, surface may be treated, titanium mica, fish phosphorus foil, Pearl agents such as bismuth oxychloride, raked Red 202, Red 228, Red 226, Yellow 4, Blue 404, Yellow 5, Red 505, Red 230, Red 223, Orange 201, Red 213, Yellow 204 No., Yellow 203, Blue No. 1, Green No. 201, Purple No. 201, Red No. 204, etc. Organic powders such as polyethylene powder, polymethyl methacrylate, nylon powder, organopolysiloxane elastomer, paraamino Benzoic acid UV absorbers, anthranilic acid UV absorbers, salicylic acid UV absorbers, cinnamic acid UV absorbers, benzophenone UV absorbers, sugar UV absorbers, 2- (2'-hydroxy-5'- UV absorbers such as t-octylphenyl) benzotriazole, 4-methoxy-4′-t-butyldibenzoylmethane, ethanol, Lower alcohols propanol, vitamin A or its derivatives, vitamin B ₆ hydrochloride, vitamin B ₆ tripalmitate, vitamin B ₆ dioctanoate, vitamin B ₂ or derivatives thereof, vitamin B _12, such as vitamin B ₁₅ or a derivative thereof Vitamin E such as vitamin B, α-tocopherol, β-tocopherol, γ-tocopherol and vitamin E acetate, vitamin D such as vitamin D, vitamin H, pantothenic acid, panthetin, pyrroloquinoline quinone and the like can be preferably exemplified. Furthermore, as the dosage form of the first agent, a lotion agent in which the α-hydroxycarboxylic acid is dissolved in an aqueous carrier is preferable. This is because the action can be neutralized promptly after the treatment is performed and the action can be stopped. The first agent of the skin external preparation kit of the present invention can be produced by treating such essential components and optional components according to a conventional method.

<2> Second agent which is an essential component of the kit for external preparation of the present invention The external preparation kit of the present invention is a person whose area of horny layer cells existing on the outermost surface of the skin is smaller than the average area. And a second agent containing a base for neutralizing the α-hydroxycarboxylic acid, which is an essential component of the skin external preparation kit for increasing the area of stratum corneum cells existing on the outermost surface of the skin. It is characterized by. As a base for neutralization, any base used in a skin external preparation can be used without any particular limitation. Alkali metal or alkaline earth metal hydroxide, carbonate, bicarbonate Suitable examples include salts, silicates, basic amino acid salts such as lysine and arginine, organic amines such as triethylamine and triethanolamine, and alkali metal or alkaline earth metal carbonates or bicarbonates. More preferred are alkali metal carbonates. In particular, sodium carbonate is preferred. Such a base is preferably used after being dissolved in an aqueous carrier at a concentration of 1 to 20% by mass, more preferably 2 to 10% by mass. In addition to this component, the second agent can contain optional components that are usually used in external preparations for skin, like the first agent. The second agent of the skin external preparation kit of the present invention can be produced by treating such essential and optional components according to a conventional method.

<3> Kit for external preparation of skin of the present invention The kit for external preparation of skin of the present invention is the outermost surface of the skin, in particular, the area of stratum corneum cells existing on the outermost surface of the skin in the face, In a small person, “the area of the horny layer cells existing on the outermost surface of the skin is smaller than the average area” can be exemplified as being smaller than the average horny layer cell area. A method for determining whether or not it is smaller than the area of the horny layer cells in the upper arm inner part of the same person can be exemplified. Even more simply, it can be exemplified by determining whether or not the average value is smaller than 500 to 700 μm ² . A skin external preparation kit for increasing the area of stratum corneum cells existing on the outermost surface of the skin, comprising 1) a first agent containing α-hydroxycarboxylic acid, and 2) the α-hydroxycarboxylic acid. The second component containing a base for neutralization is a constituent element. Here, the method of using such two agents is as follows. First, in a person whose horny layer cells existing on the outermost surface of the skin are smaller than the average area, the first liquid is administered externally and after the administration, 1 ~ 20 minutes. More preferably, it is allowed to stand for 5 to 15 minutes, and the usage form is such that the α-hydroxycarboxylic acid is quickly neutralized with the second agent, and if necessary, wiped with a skin external preparation for wiping. If this neutralization is not carried out promptly, the skin will be damaged by the action of the α-hydroxycarboxylic acid. For this reason, it is preferable to use a lotion agent dissolved in an aqueous carrier as described above. By performing such treatment, the stratum corneum cell area can be increased. Such an operation is preferably performed 2 to 6 times at a frequency of about once a week. This is because if the frequency of such treatment is too high or the frequency of treatment is too high, skin damage may occur due to the treatment. It is preferable to perform a protective treatment between these treatments so as to minimize external stimulation. Examples of such protective treatment include hyaluronic acid and / or a salt thereof, polymethacryloyloxyethoxyphosphorylcholine, a copolymer of methacryloyloxyethoxyphosphorylcholine and a hydrophobic monomer, polyglycosylethyl methacrylate, polymethacryloyl lysine, and other moisturizing polymers. 1 to 30% by mass of UV-absorbing components such as titanium dioxide or zinc oxide, which may be protected from chemical substances and water dispersion by a skin moisturizing agent with high moisture retention containing 0.01 to 5% by mass The protection from the ultraviolet rays by the skin external preparation to contain can be illustrated preferably.

The treatment is preferably performed according to the following steps.
(1) A step of collecting stratum corneum cells from the face and measuring the area thereof. At this time, when it is less than 500 μm ² , the step (2) shown below is preferably omitted and the step (3) is executed.
(2) A step of comparing the area of the horny layer cell with an average horny layer cell area. As an object to be compared, an average value of many people can be used, or it can be compared with the area of stratum corneum cells such as the inner side of the upper arm, which is difficult to receive external stimulation of the subject.
(3) A step of administering a first agent containing α-hydroxycarboxylic acid when the area of stratum corneum cells existing on the outermost surface of the skin is smaller than the average area. This administration is preferably performed so as to spread quickly over the entire face.
(4) A step of administering a second agent containing a base for neutralizing the α-hydroxycarboxylic acid 1 to 20 minutes after administration of the first agent. This step is preferably performed very quickly.
(5) A step of wiping the skin with an external preparation for wiping. As such a skin external preparation for wiping off, a form containing a lot of an aqueous carrier and a form containing a lot of moisturizing components such as glycerin is preferable.
The processing of steps (1) to (5) is performed 2 to 6 times at a frequency of about once a week. If necessary, stratum corneum cells can be collected after the treatment, the area can be measured, and the progress can be checked.

  Hereinafter, the present invention will be described in more detail with reference to examples, but it goes without saying that the present invention is not limited to these examples.

<Example 1>
From 63 volunteer panelists, the stratum corneum cells were collected from the cheek by tape stripping, stained with gentian violet, and the area of the stratum corneum cells was measured. When people having an area of less than 500 μm ² were selected, there were 26 people, and these 26 people were divided into two groups so that there was no difference between the groups. One group was treated once a week for a total of 4 times with the skin external preparation kit of the present invention shown below. The remaining 1 group was treated in the same manner with the kit for comparative external preparation for skin shown below. One week after the fourth treatment, stratum corneum cells were collected again from the cheek and the area was measured in the same manner. The results are shown in Table 1 as an average area (unit: μm ² ). From this, it can be seen that the area of stratum corneum cells is increased by the treatment with the kit for external preparation of the present invention. In addition, the following lotion was used for the skin care between each treatment.

<Kit of external preparation for skin of the present invention>
(First agent)
Glycolic acid 50 parts by mass Glycerin 5 parts by mass Water 45 parts by mass (second agent)
Sodium carbonate 10 parts by mass Glycerin 5 parts by mass Water 85 parts by mass

<Comparison skin external preparation kit>
(First agent)
Glycerin 55 parts by weight Water 45 parts by weight (second agent)
Glycerin 10 parts by weight Water 90 parts by weight

<Wipe lotion>
Glycerin 10 parts by mass 1,3-butanediol 10 parts by mass POE (60) hydrogenated castor oil 0.1 part by mass Water 79.9 parts by mass

<Skincare lotion>
Polymethacryloyl lysine 0.1 parts by mass Sodium hyaluronate 0.1 parts by mass Glycerin 10 parts by mass 1,2-hexanediol 5 parts by mass Water 84.8 parts by mass

<Measure: Common to the present invention and comparative examples>
The first agent was applied to the entire face and allowed to stand for 10 minutes, then the second agent was applied, and wiped off with a lotion contained in cut cotton. During the period from treatment to treatment, an appropriate amount of skin care lotion was applied twice a day in the morning and evening.

<Example 2>
Using the skin external preparation kit of the present invention of Example 1, the treatment time was changed to 5 minutes and 15 minutes, and the same examination was performed. The results are shown in Table 2. It can be seen that the treatment time is preferably about 10 minutes.

<Example 3>
Based on the results of Examples 1 and 2, the number of cases was reduced to 3 to examine the effect of treatment on transdermal water dispersion loss (TEWL). The treatment was carried out using the skin external preparation kit of the present invention in the same manner as in Example 1. Two weeks after the treatment, TEWL (g / m2 / hr.) Was measured using a skicon-II manufactured by iE Corporation. The results are shown in Table 3. From this table, it can be seen that by performing the treatment, the TEWL is lowered and the barrier function is improved.

<Example 4>
The three panelists of Example 3 were further followed, and the stratum corneum cells were collected and their area measured 5 weeks after the treatment, where the effects of the treatment appear to have disappeared. Furthermore, in order to confirm in detail the effect on the shape of the stratum corneum cells, the stratum corneum cells are observed with an atomic force microscope, the thickness of the stratum corneum cells and the projected area are measured, and the projected area obtained by the measurement is measured in thickness. The relative thinness (flatness) with respect to the projected area, which was multiplied by 100, was obtained. Similar values were determined in advance before treatment. The results are shown in Table 4. From this, it can be seen that even after the direct influence of the treatment disappears, the treatment works favorably on the stratum corneum cells, leads to a more flat stratum corneum cell, and improves the barrier function. From this, it is estimated that the TEWL suppression effect of Example 3 is also a result of such an effect of treatment.

  INDUSTRIAL APPLICABILITY The present invention can be applied to an external preparation for skin that increases the area of stratum corneum cells and improves the skin barrier function.

Claims (8)

A skin external preparation kit for increasing the area of horny layer cells existing on the outermost surface of a skin in a person whose area of horny layer cells existing on the outermost surface of the skin is smaller than an average area. A skin external preparation kit comprising: a first agent containing a hydroxycarboxylic acid; and 2) a second agent containing a base for neutralizing the α-hydroxycarboxylic acid. . The kit for external preparation for skin according to claim 1, wherein the α-hydroxycarboxylic acid in the first preparation of the kit for external preparation for skin is glycolic acid. The skin external preparation kit according to claim 1 or 2, wherein the content of α-hydroxycarboxylic acid in the first part of the kit for external preparation for skin is 1 to 60% by mass. The second agent containing a base for neutralizing the α-hydroxycarboxylic acid, wherein the base is an alkali metal or alkaline earth metal carbonate or bicarbonate. 3. A skin external preparation kit according to any one of 3 above. The kit for external preparation for skin according to any one of claims 1 to 4, wherein the base in the second agent containing a base for neutralizing the α-hydroxycarboxylic acid is sodium carbonate. The second agent containing a base for neutralizing the α-hydroxycarboxylic acid should be administered 1 to 20 minutes after the administration of the first agent. The skin external preparation kit of any one of Claims 1. In accordance with the following steps, the area of the stratum corneum cells existing on the outermost surface of the skin is smaller than the average area, and the area of the stratum corneum cells existing on the outermost surface of the skin is increased in a person characterized in that Process.
(1) A step of collecting horny layer cells from the face and measuring the area (2) A step of comparing the area of the horny layer cells with an average horny layer cell area (3) A horny layer cell existing on the outermost surface of the skin When the area of is smaller than the average area, the step of administering the first agent containing α-hydroxycarboxylic acid (4) 1-20 minutes after the administration of the first agent, the α-hydroxycarboxylic acid A step of administering a second agent containing a base for neutralizing an acid; and (5) a step of wiping the skin with an external preparation for wiping. The object of the present invention is to improve the ability to protect against stimulation from the outside of the skin, according to claim 7, wherein the area of the horny layer cells existing on the outermost surface of the skin is smaller than the average area, A process that increases the area of stratum corneum cells on the outermost surface.