Patent Application
20230046650
The present invention relates to a sunscreen cosmetic. More specifically, the present invention relates to a sunscreen cosmetic wherein silica having a prescribed particle size is blended with a powder having a prescribed particle size and comprising a prescribed material, thereby being able to achieve high ultraviolet protection power without blending in a large amount of ultraviolet protectants, while also providing an excellent texture and placing little strain on the skin.
Protecting the skin from damage due to ultraviolet rays is an important problem in skin care and body care, and various UV-care cosmetics for minimizing the harmful effects of ultraviolet rays on the skin have been developed. Sunscreen cosmetics, which are a type of UV-care cosmetic, are cosmetics that are intended to protect the skin from damage due to ultraviolet rays by covering the skin with a coating that film contains an ultraviolet ray absorbing agent or an ultraviolet ray scattering agent, thereby absorbing or scattering UVA and UVB rays, and limiting the amount of ultraviolet rays that reach the skin (Non-Patent Document 1).
Ultraviolet absorbing agents are blended into many sunscreen cosmetics because they are able to obtain high ultraviolet protection effects, have good compatibility with skin and are resistant to sweat and water. However, some ultraviolet absorbing agents generate heat or undergo chemical changes when ultraviolet rays are absorbed, thereby causing redness or itchiness on the skin, and further causing allergies or the like. For example, ethylhexyl methoxycinnamate (octyl methoxycinnamate) has conventionally been commonly used in sunscreen cosmetics as a representative ultraviolet absorbing agent that absorbs UVB. However, it can cause strain for users with sensitive skin. Patent Document 1 proposes blending a polypropylene glycol dimethyl ether into an external skin-care preparation in order to alleviate irritation due to ethylhexyl methoxycinnamate.
Additionally, many ultraviolet absorbing agents are solid at ambient temperature, and stably dissolving these into cosmetics without precipitation requires a suitable amount of oil. For this reason, in order to blend a large amount of ultraviolet absorbing agents, the oil amount must also be increased, and the oils can cause stickiness and degrade the feeling in use. Therefore, a water-soluble ultraviolet absorbing agent is sometimes blended instead of blending a large amount of an oil-soluble ultraviolet absorbing agent. However, in general, water-soluble ultraviolet absorbing agents tend to have inferior ultraviolet protection power in comparison with those that are oil-soluble, and it is difficult to achieve sufficient ultraviolet protection power even when a large amount of a water-soluble ultraviolet agent is blended. Additionally, in the case in which a water-soluble ultraviolet absorbing agent is blended, the stability of the cosmetic can sometimes be lowered due to the influence of salts (neutralizing salts) blended together therewith.
In consideration of these circumstances, instead of using ultraviolet absorbing agents, the use of ultraviolet scattering agents, which have relatively little irritation to the skin, has been proposed. Such cosmetics have been marketed as so-called “ultraviolet absorbing agent-free” and “non-chemical” cosmetics. For example, Patent Document 2 discloses a sunscreen cosmetic that contains a hydrophobically treated zinc oxide and/or a hydrophobically treated titanium oxide as an ultraviolet scattering agent, that does not contain an organic ultraviolet absorbing agent, and that has excellent ultraviolet protection effects, emulsion stability and feeling in use. Additionally, Patent Document 3 proposes blending multiple powder components having ultraviolet scattering functions without including ultraviolet absorbing agents, such as ethylhexyl methoxycinnamate, that cause irritation upon entering the eyes.
However, in order to obtain high ultraviolet protection effects with only an ultraviolet scattering agent, a large amount of the ultraviolet scattering agent must be blended, and there are cases in which unnatural whiteness (whitening) occurs when applied to skin, and the texture, such as the spreadability and the skin compatibility, are inferior.
Patent Document 1: JP 3683533 B
Patent Document 2: JP 5554308 B
Patent Document 3: JP 5813745 B
Non-Patent Document 1: Shin-keshohingaku, second edition, edited by Takeo Mitsui, 2001, published by Nanzando, pp. 497-504.
The present invention was made in view of the aforementioned circumstances, and an objective of the present invention is to provide a sunscreen cosmetic that increases the ultraviolet protection power of ultraviolet protectants, thereby achieving high ultraviolet protection power using only a small amount of ultraviolet protectants, while simultaneously providing an excellent texture and placing little strain on the skin.
The present inventors performed diligent research towards solving the above-mentioned problem, as a result of which they discovered that, by blending silica having a prescribed particle size with a powder having a prescribed particle size and comprising a prescribed material in a sunscreen cosmetic including an ultraviolet protectant, a uniform coating film is formed on the skin, as a result of which the ultraviolet protection power can be increased, while also further realizing an excellent texture, thus completing the present invention.
That is, the present invention is basically a sunscreen cosmetic containing the following components (A) to (C):
By having the above-mentioned features, the present invention can realize a cosmetic that can increase the ultraviolet protection power possessed by the ultraviolet protectant, while also having an excellent texture. Additionally, the present invention can provide a sunscreen cosmetic that is highly safe because the ultraviolet absorbing agent that can place strain on the skin is held to a small amount. Furthermore, high ultraviolet protection effects are achieved even without blending in a large amount of an ultraviolet scattering agent. Thus, whitening and poor skin compatibility, which are characteristic of ultraviolet scattering agents, do not tend to occur.
The sunscreen cosmetic of the present invention is characterized by containing (A) an ultraviolet protectant, (B) silica having a prescribed particle size, and (C) a powder having a prescribed particle size and comprising a prescribed material. Hereinafter, the components constituting the cosmetic of the present invention will be described in detail.
The (A) ultraviolet protectant blended in the sunscreen cosmetic of the present invention refers to an ultraviolet absorbing agent and/or an ultraviolet scattering agent, and one that is normally blended in cosmetics may be used.
Ultraviolet absorbing agents include, for example, benzoic acid derivatives, salicylic acid derivatives, cinnamic acid derivatives, dibenzoyl methane derivatives, β,β-diphenyl acrylate derivatives, benzophenone derivatives, benzylidene camphor derivatives, phenylbenzimidazole derivatives, triazine derivatives, phenylbenzotriazole derivatives, anthranil derivatives, imidazoline derivatives, benzalmalonate derivatives, 4,4-diaryl butadiene derivatives and the like. Hereinafter, specific examples and product names will be mentioned, but there is no limitation thereto.
Examples of benzoic acid derivatives include ethyl para-aminobenzoate (PABA), ethyl-dihydroxypropyl PABA, ethylhexyl-dimethyl PABA (e.g., “Escalol 507”; ISP), glyceryl PABA, PEG-25-PABA (e.g., “Uvinul P25”; BASF), diethylamino hydroxybenzoyl hexyl benzoate (e.g., “Uvinul A Plus”) and the like.
Examples of salicylic acid derivatives include homosalate (“Eusolex HMS”; Rona/EM Industries), ethylhexyl salicylate or octyl salicylate (e.g., “Neo Heliopan OS”; Haarmann & Reimer), dipropylene glycol salicylate (e.g., “Dipsal”; Scher), TEA salicylate (e.g., “Neo Heliopan TS”; Haarmann & Reimer) and the like.
Examples of cinnamic acid derivatives include octyl methoxycinnamate or ethylhexyl methoxycinnamate (e.g., “Parsol MCX”; Hoffmann-La Roche), isopropyl methoxycinnamate, isoamyl methoxycinnamate (e.g., “Neo Heliopan E1000”; Haarmaan & Reimer), cinnoxate, DEA methoxycinnamate, diisopropyl methyl cinnamate, glyceryl ethylhexanoate dimethoxycinnamate, di-(2-ethylhexyl)-4’-methoxybenzalmalonate and the like.
Examples of dibenzoyl methane derivatives include 4-tert-butyl-4’-methoxy dibenzoyl methane (e.g., “Parsol 1789”) and the like.
Examples of β,β-diphenyl acrylate derivatives include octocrylene (e.g., “Uvinul N539T”; BASF) and the like.
Examples of benzophenone derivatives include benzophenone-1 (e.g., “Uvinul 400”; BASF), benzophenone-2 (e.g., “Uvinul D50”; BASF), benzophenone-3 or oxybenzone (e.g. “Uvinul M40”; BASF), benzophenone-4 (e.g., “Uvinul MS40”; BASF), benzophenone-5, benzophenone-6 (e.g., “Helisorb 11”; Norquay), benzophenone-8 (e.g., “Spectra-Sorb UV-24”; American Cyanamid), benzophenone-9 (e.g., “Uvinul DS-49”; BASF), benzophenone-12 and the like.
Examples of benzylidene camphor derivatives include 3-benzylidene camphor (e.g., “Mexoryl SD”; Chimex), 4-methylbenzylidene camphor, benzylidene camphor sulfonic acid (e.g., “Mexoryl SL”; Chimex), camphor benzalkonium methosulfate (e.g., “Mexoryl SO”; Chimex), terephthalylidene dicamphor sulfonic acid (e.g., “Mexoryl SX”; Chimex), polyacrylamide methylbenzylidene camphor (e.g., “Mexoryl SW”; Chimex) and the like.
Examples of phenylbenzimidazole derivatives include phenylbenzimidazole sulfonic acid (e.g., “Eusolex 232”; Merck), disodium phenyldibenzimidazole tetrasulfonate (e.g., “Neo Heliopan AP”; Haarmann & Reimer) and the like.
Examples of triazine derivatives include bis-ethylhexyloxyphenol methoxyphenyl triazine (e.g., “Tinosorb S”; Ciba Specialty Chemicals), ethylhexyl triazone (e.g., “Uvinul T150”; BASF), diethylhexyl butamido triazone (e.g., “Uvasorb HEB”; Sigma 3V), 2,4,6-tris(diisobutyl-4'-aminobenzalmalonate)-s-triazine, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine and the like.
Examples of phenylbenzotriazole derivatives include drometrizole trisiloxane (e.g., “Silatrizole”; Rhodia Chimie), methylene bis(benzotriazolyl tetramethylbutyl phenol) (e.g., “Tinosorb M” (Ciba Specialty Chemicals)) and the like.
Examples of anthranil derivatives include menthyl anthranilate (e.g., “Neo Heliopan MA”; Haarmann & Reimer) and the like.
Examples of imidazoline derivatives include ethylhexyl dimethoxybenzylidene dioxoimidazoline propionate and the like.
Examples of benzalmalonate derivatives include polyorganosiloxanes having benzalmalonate functional groups (e.g., Polysilicone-15; “Parsol SLX”; DSM Nutrition Japan) and the like.
Examples of 4,4-diarylbutadiene derivatives include 1,1-dicarboxy (2,2’-dimethylpropyl)-4,4-diphenylbutadiene and the like.
Among the examples of the ultraviolet absorbing agent, octocrylene, octyl salicylate and homosalate are particularly preferred, and at least one of the above is preferably included.
The ultraviolet scattering agent is not particularly limited, and for example, may be a fine-particle metal oxide such as, for example, zinc oxide, titanium oxide, iron oxide, cerium oxide and tungsten oxide.
The ultraviolet scattering agent may be non-surface-treated or may be treated with various types of hydrophobic surface treatments, but those that are hydrophobically surface-treated are preferably used. As the surface treatment agent, it is possible to use a type that is commonly used in the cosmetics field including, for example, a silicone such as dimethicone or alkyl-modified silicone, an alkoxysilane such as octyltriethoxysilane, a dextrin fatty acid ester such as dextrin palmitate, or a fatty acid such as stearic acid.
The present invention includes embodiments in which the (A) ultraviolet protectant consists only of an ultraviolet absorbing agent, embodiments in which it consists only of an ultraviolet scattering agent, and embodiments in which it includes both an ultraviolet absorbing agent and an ultraviolet scattering agent.
The blended amount of the (A) ultraviolet protectant should preferably be 5% to 40% by mass, more preferably 10% to 30% by mass, and even more preferably 10% to 20% by mass relative to the total amount of the sunscreen cosmetic. If the blended amount of the (A) ultraviolet protectant is less than 5% by mass, then sufficient ultraviolet protection effects are difficult to obtain, and even if more than 40% by mass is blended, an increase in the ultraviolet protection effects commensurate with the blended amount cannot be expected, and the stability and texture are worsened.
The (B) silica blended into the sunscreen cosmetic of the present invention is a silica having a particle size of 0.3 to 1 µm, preferably 0.4 to 1 µm and more preferably 0.5 to 1 µm. As long as the particle size is within this range, those that are normally used in cosmetics may be used without restriction. In the present specification, “particle size” refers to the value as measured by a particle size analyzer based on the laser diffraction/scattering method.
The shape of the (B) silica is preferably spherical, and more preferably, perfectly spherical, for being able to obtain a smooth and favorable sensation to the touch. In the present invention, perfectly spherical refers to having a substantially perfectly circular shape when viewed in projection from any direction, such that the minimum value of the particle size is at least 80%, more preferably at least 90%, of the maximum value.
Additionally, as the (B) silica, one that has been subjected to a hydrophobic treatment may be used. The hydrophobic treatment agent is not particularly limited and the silica may, for example, be prepared by being coating with an organosilane-based compound, a silicone compound, a fluorine compound or the like. More specifically, examples include dimethylsilylated silica, trimethylsilylated silica, octylsilylated silica, silicone oil-treated silica, methylpolysiloxane-treated silica, metal soap-treated silica, amino acid-treated silica, higher alcohol-treated silica, mineral-based wax-treated silica and the like.
A commercial product may be used as the (B) silica, and for example, “COSMO 55” (JGC Catalysts and Chemicals) or the like can be favorably used.
The blended amount of the (B) silica should preferably be 0.2% to 2% by mass, more preferably 0.2% to 1.5% by mass, and even more preferably 0.2% to 1% by mass relative to the total amount of the sunscreen cosmetic. If the blended amount of the (B) silica is less than 0.2% by mass, then sufficient ultraviolet protection increase effects are difficult to obtain, and if more than 2% by mass is blended, then the texture tends to become worse.
The (C) powder blended into the sunscreen cosmetic of the present invention is one that is normally blended into cosmetics in order to improve the texture, and is of one or more types selected from the group consisting of silica, aluminum starch octenyl succinate, cellulose or derivatives thereof, waxes, mica, sericite and biodegradable resins. Additionally, the above substances with the surfaces thereof subjected to hydrophobic treatments may be used.
The (C) powder has a particle size of 1 to 30 µm, preferably 4 to 20 µm and more preferably 4 to 10 µm. If the particle size is outside said range, then there are cases in which sufficient texture improvement effects cannot be obtained. The shape of the (C) powder, like the (B) silica, is preferably spherical, and more preferably, perfectly spherical, for being able to obtain a smooth and favorable feeling to the touch.
The silica that can be used as the (C) powder differs from the (B) silica in that the particle size is larger. Commercial products include, for example, “Sunsphere L-51” (AGC Si-Tech), etc. Aluminum starch octenyl succinate is an aluminum salt that is the reaction product of octenyl succinic anhydride with starch. Since it has oil-absorbing properties, it is sometimes used in cosmetics in order to improve stickiness and the like. As a commercial product, for example, “TAPIOCA SDS” (Bo-kwang) or the like may be favorably used.
Cellulose or derivatives thereof include, aside from cellulose, derivatives in which hydroxyl groups in the cellulose molecule have been substituted, such as, for example, spherical cellulose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose and methylhydroxypropyl cellulose.
The waxes are those that have been powdered by pulverization or the like of a wax having a melting point of 80° C. or higher, and are not particularly limited as long as they can be blended into cosmetics. Such waxes can be obtained by powdering a wax, such as carnauba wax, a synthetic hydrocarbon wax, a polyethylene wax, an ethylene-propylene copolymer wax or a Fischer-Tropsch wax, by means of a method of mechanical pulverization, such as by a jet pulverizer, or a method of dissolving the wax in a volatile solvent and spray-drying the solution. As commercial products, PRESS-AID-SP, PRESS-AID-XP (both by Presperse) and the like may be used.
Mica and sericite are both lamellar silicic acid salts that are widely used in cosmetics as extender pigments and the like. Biodegradable resins include polyester-based resins such as poly-lactic acids, polyester amide-based resins, polyester carbonate-based resins, polysaccharides, polypeptides, lignins and derivatives thereof.
The blended amount of the (C) powder should preferably be 0.5% to 20% by mass, more preferably1% to 10% by mass, and even more preferably 1% to 5% by mass relative to the total amount of the sunscreen cosmetic. If the blended amount of the (C) powder is outside the above-mentioned range, then the texture mainly tends to become worse.
Although the blended mass ratio between the (B) silica and the (C) powder is not particularly limited, the relation (B) < (C) is preferably satisfied. That is, the blended amount of the (C) powder is preferably greater than the blended amount of the (B) silica. By setting the blended amount of the (C) powder to be greater than that of the (B) silica, particularly excellent effects tend to be obtained in terms of both the ultraviolet protection increase effects and the texture.
The sunscreen cosmetic of the present invention may further contain a powder such as silica or aluminum starch octenyl succinate having a particle size different from that of the (B) silica or the (C) powder, as long as it is within a range not compromising the effects of the present invention.
Aside from the above-mentioned components (A) to (C), components that are normally used in cosmetics may be blended into the sunscreen cosmetic of the present invention within a range not compromising the effects of the present invention.
For example, oil-based components, water-based components, alcohols, humectants, thickeners, surfactants, film agents, powder components, ultraviolet scattering agents, stabilizers, chelating agents, preservatives, fragrances and the like may be appropriately blended as needed.
The sunscreen cosmetic of the present invention can be provided in any format, such as a water-based cosmetic, an oil-based cosmetic, an oil-in-water emulsion cosmetic or a water-in-oil emulsion cosmetic. Specific formats include toners, emulsions, creams, lotions, sprays and the like, which can be manufactured by using conventional methods that are appropriate for the respective formats.
Although the present invention will be explained in further detail by providing examples below, the present invention is not limited in any way thereby. Where not otherwise noted, the blended amounts are indicated in percentage by mass relative to the total amount of the sunscreen cosmetic. Before specifically explaining each example, the evaluation methods that were employed will be explained.
Cosmetics (samples) according to each example were dripped, at a rate of 2 mg/cm2, onto measurement plates (S plates) (5 × 5 cm V-groove PMMA (polymethyl methacrylate) plates, SPFMASTER-PA01), applied by finger for 60 seconds and dried for 15 minutes to form coating films, the absorbances of which were measured using a Hitachi U-3500 self-recording spectrophotometer. The absorbances (Abs) were computed, with an uncoated plate as the control, by using the following equation, and the measurement values were integrated from 280 nm to 400 nm to determine the absorbance integral value. Abs = -log (T/To) T: transmittance of sample, To: transmittance of uncoated plate
From the absorbance integral values of the samples that were determined, the ultraviolet protection power increase rates, relative to a control sample (Comparative Example 1) in which (B) the silica and (C) the powder were not blended, were computed by the following equation. [Ultraviolet protection power increase rate (%)] = [Absorbance integral value of sample] / [Absorbance integral value of Comparative Example 1] × 100
The computed ultraviolet protection power increase rates were assessed by the evaluation scoring criteria below. Evaluation criteria
Samples of the examples and comparative examples were actually used by ten expert panelists and evaluated regarding texture (lack of stickiness, wateriness). A five-level organoleptic evaluation was performed by each panelist in accordance with the evaluation scoring criteria below, and assessments were made based on the below-mentioned evaluation criteria in accordance with the total points scored.
Evaluation scoring criteria
Evaluation criteria
Water-in-oil sunscreen cosmetics having the compositions described in Table 1 below were prepared. The ultraviolet protection power increase rates and the textures were evaluated in accordance with the above-mentioned evaluation methods.
As indicated in Table 1 above, when silica corresponding to component (B) and silica corresponding to component (C) were both blended, clear increase effects were observed in the ultraviolet protection power, and excellent results were also obtained regarding the texture (Examples 1 and 2), in comparison with the case in which these were not blended (Comparative Example 1).
However, in the case in which only silica corresponding to component (B) was blended, although an increase in the ultraviolet protection power was observed, the texture was markedly inferior (Comparative Example 2). Additionally, in the case in which only silica corresponding to component (C) was blended, although the texture was excellent, an increase in the ultraviolet protection power was not observed (Comparative Example 3).
Furthermore, even in the case in which silica having a particle size much smaller than that in Comparative Example 2 was blended, an increase in the ultraviolet protection power was observed (Comparative Example 4). However, even when silica corresponding to component (C) was blended in combination therewith, an ultraviolet protection power increase effect and excellent texture were not able to be realized simultaneously (Comparative Example 5).
Additionally, when a spherical PMMA powder or a (vinyl dimethicone/methicone silsequioxane) crosspolymer, which have been generally used as powders for improving the texture in normal cosmetics, was blended, excellent results were indeed exhibited regarding the texture (Comparative Examples 6 and 8). However, even when these were combined with the silica corresponding to component (B), the ultraviolet protection power was not able to be sufficiently increased (Comparative Examples 7 and 9).
Water-in-oil sunscreen cosmetics having the compositions described in Table 2 below were prepared, and the ultraviolet protection power increase rate and the texture were evaluated in accordance with the above-mentioned evaluation methods. However, in the evaluation of the ultraviolet protection power increase rate, Comparative Example 10 was used as the control sample instead of Comparative Example 1.
As indicated in Table 2 above, when silica corresponding to component (B) and silica or aluminum starch octenyl succinate corresponding to component (C) were blended, clear increase effects were observed in the ultraviolet protection power, and excellent results were also obtained regarding the texture (Examples 3 to 6), in comparison with the case in which these were not blended (Comparative Example 10).
However, in the case in which only aluminum starch octenyl succinate corresponding to component (C) was blended, although the texture was excellent, the ultraviolet protection power was not able to be sufficiently increased (Comparative Example 11).
Hereinafter, examples of formulations of the cosmetic of the present invention will be indicated. Needless to say, the present invention is not limited in any way by these formulation examples, and is as defined by the claims. The blended amounts are all indicated in percentage by mass relative to the entire cosmetic.
Formulation Example 1: Oil-in-water sunscreen cosmetic
Formulation Example 2: Oil-based sunscreen cosmetic
Formulation Example 3: Oil-in-water sunscreen cosmetic
Formulation Example 4: Oil-in-water sunscreen cosmetic
Formulation Example 5: Water-in-oil sunscreen cosmetic
Formulation Example 6: Water-in-oil sunscreen cosmetic
| Number | Date | Country | Kind |
|---|---|---|---|
| 2019-226164 | Dec 2019 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2020/046912 | 12/16/2020 | WO |
