JP2022069350A - Sunscreen composition - Google Patents

Abstract

To provide a sunscreen composition that can sufficiently moisturize even a dry skin, lightens squeaking of skin caused by an ultraviolet scattering agent, and makes dry skin have a natural finish.SOLUTION: A sunscreen composition contains a component (A) by 0.01 to 0.5 mass%, a component (B) by 5 to 40 mass%, and a component (C) by 0.1 to 10 mass%. The component (A) is a (meth)acrylic copolymer which includes a constituent unit expressed by formula (I) and a constituent unit expressed by formula (II) of Claim 1, in which a molar ratio (I/II) of both constituent units is 90/10 to 30/70. The component (B) is an ultraviolet scattering agent. The component (C) is hydrogenated polyisobutene having the number-average molecular weight of 100 to 3000.SELECTED DRAWING: None

Description

The present invention relates to a sunscreen composition that can sufficiently moisturize dry skin, reduce skin squeak caused by an ultraviolet scattering agent, and give dry skin a natural finish.

The sunscreen composition has the function of protecting the skin from damage caused by ultraviolet rays. The components that block UV rays are roughly divided into UV absorbers and UV scatterers, but UV scatterers have the image of being less irritating to the skin than UV absorbers, so they are especially for sensitive skin and babies. It is widely used in such fields. However, the ultraviolet scattering agent has problems such as dry skin, squeaking, unevenness, and easy powder floating of makeup when used.

As an example of improving the dry feeling due to the ultraviolet scattering agent, for example, Patent Document 1 proposes a skin external preparation that imparts moisturizing properties by combining metal oxide particles, closed vesicles or polycondensation polymers, and a moisturizing agent. There is. However, this external skin preparation was insufficient in terms of skin squeak.

Further, in Patent Document 2, a sunscreen makeup that improves the squeaky and dry feeling of the skin after application by combining fine particle zinc oxide surface-treated with N-acylamino acid or a salt thereof, volatile oil, and trimethylsiloxysilicic acid. Fees are provided. However, this cosmetic was inadequate in terms of the natural finish of the skin.

On the other hand, in Patent Document 3, the combination of iron oxide-coated titanium oxide, cross-linked organopolysiloxane, and spherical silicone elastic powder suppresses conspicuous pores and stains and uneven streaks during application to finish the skin naturally. Water-in-oil emulsified cosmetics have been proposed. However, this cosmetic was not sufficient for the natural finish even on dry skin.

Japanese Unexamined Patent Publication No. 2016-74656 Japanese Unexamined Patent Publication No. 2018-8910 Japanese Unexamined Patent Publication No. 2019-26620

In view of the above problems, it is an object of the present invention to provide a sunscreen composition that can sufficiently moisturize dry skin, reduce skin squeak caused by an ultraviolet scattering agent, and give dry skin a natural finish.

As a result of diligent studies in view of the above problems, the present inventors have contained a structural unit having a side chain containing a urethane bond and a glycerol skeleton and a structural unit having a long-chain alkyl chain at the end of the side chain in a specific amount ratio. We have found that a sunscreen composition that can solve the above-mentioned problems can be obtained by combining a specific (meth) acrylic copolymer, an ultraviolet scattering agent, and a specific hydrocarbon in a predetermined blending amount, and the present invention has been made. It was completed.

That is, the present invention is a sunscreen composition containing 0.01 to 0.5% by mass of the component (A), 5 to 40% by mass of the component (B), and 0.1 to 10% by mass of the component (C). Is.

Component (A): Contains a structural unit represented by the following formula (I) and a structural unit represented by the following formula (II), and the molar ratio (I / II) of both constituent units is 90/10 or more. 30/70 (meth) acrylic copolymer

(In the formula, R ¹ represents a hydrogen atom or a methyl group, R ² represents-(CH ₂ ) n-, n is an integer of 1 to 4. * represents a binding site with another constituent unit. .)

(In the formula, R ³ represents a hydrogen atom or a methyl group, and L ¹ is phenylene, cyclohexylene, -C (= O) -O-, -O-, -C (= O) -NH-, -O-. It represents C (= O)-or-OC (= O) -O-, L ² represents a linear or branched alkyl group having 10 to 22 carbon atoms, and * represents a binding site with another structural unit. Represents.)
Component (B): Ultraviolet scattering agent Component (C): Hydrogenated polyisobutene having a number average molecular weight of 100 to 3000

According to the sunscreen composition of the present invention, even dry skin can be sufficiently moisturized, squeaky skin due to an ultraviolet scattering agent can be reduced, and dry skin can be given a natural finish.

Hereinafter, embodiments of the present invention will be described.
In the present specification, "(meth) acryloyl" means both "acryloyl" and "methacrylic acid", and "(meth) acrylic" means both "acrylic" and "methacrylic".
In addition, the numerical range defined by using the symbol "-" in the present specification shall include the numerical values at both ends (upper limit and lower limit) of "-". For example, "2 to 5" represents 2 or more and 5 or less.

The sunscreen composition of the present invention contains at least component (A), component (B) and component (C). Hereinafter, each component will be described.

[Component (A)]
The component (A) used in the present invention is a (meth) acrylic copolymer containing a structural unit represented by the following formula (I) and a structural unit represented by the following formula (II).

In the formula (I), R ¹ represents a hydrogen atom or a methyl group, and a methyl group is preferable from the viewpoint of stability of the copolymer. R ² represents − (CH ₂ ) n −, and n is an integer of 1 to 4. That is, R ² is any of-(CH ₂ )-,-(CH ₂ ) ₂ -,-(CH ₂ ) ₃ -,-(CH ₂ ) ₄ --(CH 2) 4-( CH ₂ ) ₂ -is preferable.

Specific examples of the monomer forming the structural unit of the formula (I) include glycerol-1-methacryloyloxyethylene urethane, glycerol-1-methacryloyloxypropylene urethane, and the like. Glycerol-1-methacryloyloxyethylene urethane is preferable because of its ease of synthesis.

The monomer forming the structural unit of the formula (I) can be synthesized by a known method. For example, it can be synthesized by the method described in JP-A-2007-119374 or the like or a method similar thereto. As a specific method, for example, a compound obtained by subjecting a cyclic ketal to a (meth) acryloyloxyalkylene isocyanate in a urethanization reaction is subjected to a ring-opening reaction in a water-containing solvent in the presence of a urethanization reaction catalyst. The method and the like can be mentioned.

In the formula (II), R ³ represents a hydrogen atom or a methyl group, and a methyl group is preferable from the viewpoint of the stability of the copolymer. L ¹ is phenylene, cyclohexylene, -C (= O) -O-, -O-, -C (= O) -NH-, -OC (= O)-, or -OC (= O). ) -O-, and more preferably -O-. L ² represents a linear or branched alkyl group having 10 to 22 carbon atoms, preferably 15 to 20 carbon atoms, and examples thereof include a hexadecyl group, a heptadecyl group, and an octadecyl group.

Specific examples of the monomer forming the structural unit of the formula (II) include hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate and the like, and among them, octadecyl (meth) acrylate. Is preferable.

The molar ratio (I / II) of the structural unit of the formula (I) to the structural unit of the formula (II) in the component (A) is 90/10 to 30/70. If the proportion of the constituent units of formula (I) is larger than this range, the skin may become sticky and the skin may become squeaky, and if the proportion of the constituent units of formula (II) is large, the solubility in water decreases. Therefore, it may be difficult to obtain a stable composition. From the above points, the molar ratio (I / II) is preferably 80/20 to 40/60, more preferably 70/30 to 50/50.

The (meth) acrylic copolymer of the component (A) may contain other structural units in addition to the structural unit of the formula (I) and the structural unit of the formula (II). Examples of the monomer forming such another structural unit include isobornyl methacrylate, ethyltrimethylammonium chloride chloride and the like. When the (meth) acrylic copolymer of the component (A) contains a structural unit other than the structural unit of the formula (I) and the structural unit of the formula (II), the content of the other structural units in the copolymer. Is preferably 10 mol% or less with respect to the total amount of the structural unit of the formula (I) and the structural unit of the formula (II).
The (meth) acrylic copolymer of the component (A) may be a random copolymer or a block copolymer, but a random copolymer is preferable.

The weight average molecular weight (Mw) of the copolymer of the component (A) is preferably 5,000 to 500,000, more preferably 10,000, from the viewpoint of the effect of giving the skin a natural finish and the ease of blending. ~ 200,000. The component (A) may be diluted with a polyhydric alcohol such as glycerin or 1,3-butylene glycol for ease of handling.
The weight average molecular weight (Mw) of the copolymer is measured by a gel permeation chromatography (GPC) method (polyethylene glycol equivalent). For the weight average molecular weight by the GPC method, prepare a sample solution using a methanol / chloroform mixed solvent (6/4 (volume ratio)) containing 0.5% by mass of lithium bromide, and use a standard polyethylene glycol calibration curve. Can be calculated.

The component (A) is polymerized by a known method using a monomer composition containing at least a monomer as a constituent unit of the formula (I) and a monomer as a constituent unit of the formula (II). Can be prepared. For example, a monomer composition satisfying the molar ratio (I / II) of the above-mentioned structural unit is prepared, and is prepared by solution polymerization in the presence of a radical polymerization initiator in an atmosphere of an inert gas such as nitrogen. Can be done.

Further, instead of preparing the component (A), a commercially available product can also be used. Examples of commercially available products of the component (A) include "CERACUTE-L" manufactured by NOF CORPORATION.
This commercially available product (trade name "CERACUTE-L") is a product obtained by diluting the component (A) with glycerin and 1,3-butylene glycol, and the component (A) is glyceryl-N- (2-methacryloyloxyethyl). ) Carbamate-Contains stearyl methacrylate copolymer. In this copolymer, R ¹ represents a methyl group and R ² represents- (CH ₂ ) _2- in the formula (I), L ¹ represents an -O-, L ² represents an octadecyl group, and R ³ in the formula (II). Represents a methyl group, and the molar ratio (I / II) of both constituent units is 60/40.

The content of the component (A) in the sunscreen composition of the present invention is 0.01 to 0.5% by mass, preferably 0.03 to 0.25% by mass, and more preferably 0 in the total amount of the composition. It is 0.05 to 0.15% by mass. If the content of the component (A) is too low, it may not be possible to obtain a sufficient moisturizing feeling and the effect of giving a natural finish to dry skin, and if the content of the component (A) is too high, it may cause stickiness and squeak. It feels and may reduce the stability of the sunscreen composition.

[Component (B)]
The component (B) used in the present invention is an ultraviolet scattering agent, and is blended for the purpose of scattering or shielding ultraviolet rays. As the ultraviolet scattering agent, any one generally used in cosmetics can be used without any problem, but titanium oxide and zinc oxide are preferable, and those obtained by atomizing them are more preferable. Further, an ultraviolet scattering agent surface-treated (coated) with fatty acid, silicone, or the like may be used.

As these ultraviolet scattering agents, a simple substance may be obtained and used, or a commercially available product in which a metal oxide is stably converted into low-order particles in an oil agent may be used. Examples of the oil agent used for lowering the particle size of the metal oxide include silicone oil, ester oil, and hydrocarbon oil. Examples of such commercially available products include "IOPP60ZIAJ" and "IOPP50TIJ" manufactured by KOBO Dispatec Co., Ltd., "DIF-3ST2" and "DIS-11A" manufactured by Sakai Chemical Industry Co., Ltd.
"IOPP60ZIAJ" manufactured by KOBO Dispatec Co., Ltd. consists of zinc oxide, ethylhexyl palmitate, isostearic acid and polyhydroxystearic acid, and "IOPP50TIJ" consists of titanium oxide, ethylhexyl palmitate, aluminum hydroxide, isostearic acid and polyhydroxystearic acid. Consists of. "DIF-3ST2" manufactured by Sakai Chemical Industry Co., Ltd. is composed of zinc oxide, cyclopentasiloxane and hydrogendimethicone, and "DIS-11A" is composed of titanium oxide, cyclopentasiloxane, hydrous silica, aluminum hydroxide and hydrogendimethicone.
As the component (B), one type can be used alone, or two or more types can be used in combination.

The content of the component (B) in the sunscreen composition of the present invention is 5 to 40% by mass, preferably 10 to 30% by mass, and more preferably 15 to 25% by mass in the total amount of the composition. If the content of the component (B) is too small, a sufficient UV protection effect may not be obtained as a sunscreen composition, and if the content of the component (B) is too large, the skin may be squeaky or dry. May adversely affect the feeling.

[Component (C)]
The component (C) used in the present invention is hydrogenated polyisobutene having a number average molecular weight of 100 to 3000, and is usually obtained by hydrogenating a polymer of isobutene and n-butene. The number average molecular weight of hydrogenated polyisobutene is preferably 200 to 2500, more preferably 1000 to 2000, and particularly preferably 1250 to 1750, from the viewpoint of moisturizing feeling and reducing stains. If the number average molecular weight (or molecular weight) of hydrogenated polyisobutene is too low, the moisturizing feeling may be insufficient, and if the number average molecular weight (or molecular weight) is too high, the skin may become squeaky or evenly applied to the skin. May become difficult and the effect of finishing the skin naturally may be weakened.
The number average molecular weight (Mn) of hydrogenated polyisobutene can be calculated by gel filtration chromatography (GFC) analysis.

Commercially available hydrogenated polyisobutenes include NOF Corporation's "Pearl Ream 3" (number average molecular weight: 217), "Pearl Ream 4" (number average molecular weight: 272), and "Pearl Ream 18" (number average molecular weight). 1122) "Pearl Ream 24" (number average molecular weight: 1653) and the like can be mentioned.
As the component (C), one type can be used alone, or two or more types of hydrogenated polyisobutene having different number average molecular weights can be used in combination.

The content of the component (C) in the sunscreen composition of the present invention is 0.1 to 10% by mass, preferably 0.3 to 4% by mass, and more preferably 0.5 to 2 in the total amount of the composition. It is mass%. If the content of the component (C) is too low, it may be insufficient in terms of moisturizing feeling and no squeak, and if the content of the component (C) is too high, stickiness may occur or the skin may be uniform. It may be difficult to apply to the skin and the effect of finishing the skin naturally may be weakened.

[Other ingredients]
The sunscreen composition of the present invention usually contains water in addition to the above components (A) to (C). Examples of water include purified water, tap water, industrial water, deionized water and the like.
The content of water in the sunscreen composition of the present invention is usually 30 to 90% by mass, preferably 40 to 80% by mass, more preferably 45 to 75% by mass, and particularly preferably 50% of the total amount of the composition. It is ~ 70% by mass.

In the sunscreen composition of the present invention, the total content of the above components (A) to (C) and water is 35.11 to 100% by mass, preferably 40 to 95% by mass, more preferably 40 to 95% by mass, based on the total amount of the composition. It is preferably 45 to 90% by mass.

The sunscreen composition of the present invention is used in cosmetics, quasi-drugs, pharmaceuticals, etc., if necessary, in addition to the above components (A) to (C) and water, as long as the object of the present invention is not impaired. It may contain an additive to be added.
Examples of such an additive include a surfactant, and the surfactant is preferably a nonionic surfactant, and examples thereof include a polyglyceryl type surfactant and a sorbitan type surfactant. As these surfactants, one kind or two or more kinds can be appropriately selected and used as needed.
Among these, sorbitan-type surfactants are preferable, and sorbitan sesquiisostearate is particularly preferable because it is easy to obtain the effect of giving a natural finish to dry skin. Examples of commercially available products include "NIKKOLSI-15RV" manufactured by Nikko Chemicals Co., Ltd.
When the sunscreen composition of the present invention contains sorbitan sesquiisostearate, the content thereof is usually 0.01 to 4% by mass, preferably 0.1 to 3% by mass, more preferably 0.1 to 3% by mass, based on the total amount of the composition. It is preferably 0.3 to 2% by mass.

The sunscreen composition of the present invention can be provided as a sunscreen cosmetic in various forms, and can be applied to the skin such as face and skin as a sunscreen cosmetic, for example.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.
[Examples 1 to 5, Comparative Examples 1 to 3]
Ingredients (A), (B-1), (B-2), (C-1), (C-2), (A'), 12 kinds of common additives shown in Table 3, and purified water were used. Sunscreen cosmetics having the compositions shown in Tables 1 and 2 were prepared and evaluated by the methods (1) to (3) below. The compounding ingredients shown in Tables 1 and 2 are shown below.

Ingredient (A): "Ceracute-L" (manufactured by NOF CORPORATION) (Active ingredient: Glyceryl-N- (2-methacryloyloxyethyl) carbamate / stearyl methacrylate copolymer)
Ingredient (A'): "SOLTEX INO Polymer" (manufactured by Dow Chemical Japan Co., Ltd.) (Active ingredient: (Acrylate / Methacryloyloxyethyl Phosphate) Copolymer)
Ingredient (B-1): "DIS-11A" (manufactured by Sakai Chemical Industry Co., Ltd.) (Active ingredient: Titanium oxide (34%), Other ingredients: Hydrous silica, aluminum hydroxide, hydrogen dimethicone, cyclopentasiloxane)
Ingredient (B-2): "DIF-3ST2" (manufactured by Sakai Chemical Industry Co., Ltd.) (Active ingredient: Zinc oxide (48%), Other ingredients: Hydrogen dimethicone, Cyclopentasiloxane)
Ingredient (C-1): "Pearl Ream 4" (manufactured by NOF CORPORATION) (Active ingredient: Hydrogenated polyisobutene (number average molecular weight: 272))
Ingredient (C-2): "Pearl Ream 24" (manufactured by NOF CORPORATION) (Active ingredient: Hydrogenated polyisobutene (number average molecular weight: 1653))
12 types of common additives: The 12 types of common additives shown in Tables 1 and 2 are composed of the 12 types of components shown in Table 3. In Table 3 and the following, PEG represents polyethylene glycol, VP represents vinylpyrrolidone, and BG represents 1,3-butylene glycol.
The content of each component shown in Tables 1 and 2 is the content of the active ingredient.

〔Evaluation methods〕
The (1) moisturizing feeling, (2) no squeaky skin, and (3) the natural finish of dry skin were evaluated on a four-point scale according to the following criteria.

(Judgment criteria)
(1) Moisturizing sensation Twenty women (23-55 years old) were used as panelists to evaluate the moisturizing sensation of the skin after applying sunscreen cosmetics to the face.
2 points: I felt a moisturizing feeling.
1 point: I felt a little moisturizing.
0 points: I did not feel the moisturizing feeling.

The total score of 20 people was calculated and judged as follows.
⊚: Total score is 30 points or more: Sunscreen cosmetic with moisturizing feeling.
◯: Total score is 20 points or more and less than 30 points: Sunscreen cosmetic with a slightly moisturizing feeling.
Δ: Total score is 10 points or more and less than 20 points: Sunscreen cosmetic without moisturizing feeling.
X: Total score is less than 10 points: Sunscreen cosmetic with no moisturizing feeling.

(2) No skin squeaks Twenty women (23-55 years old) were used as panelists to evaluate the squeaky condition of the skin after applying sunscreen cosmetics to the face.
2 points: No squeak was felt.
1 point: A slight squeak was felt.
0 points: I felt a squeak.

The total score of 20 people was calculated and judged as follows.
⊚: Total score is 30 points or more: Sunscreen cosmetic that does not damage the skin.
◯: Total score is 20 points or more and less than 30 points: Sunscreen cosmetic that does not cause skin irritation.
Δ: Total score is 10 points or more and less than 20 points: Sunscreen cosmetics that squeak the skin.
X: Total score is less than 10 points: Sunscreen cosmetics that make the skin squeaky.

(3) Natural finish of dry skin Twenty women (23-55 years old) with dry skin were used as panelists to evaluate the finish of the skin after applying sunscreen cosmetics to the face.
2 points: The skin has a natural finish even on dry skin.
1 point: Even with dry skin, the skin has a slightly natural finish.
0 points: There was no change, or the dry skin did not have a natural finish.

The total score of 20 people was calculated and judged as follows.
⊚: Total score is 30 points or more: The effect of giving a natural finish to dry skin is very high.
◯: Total score is 20 points or more and less than 30 points: The effect of giving a natural finish to dry skin is high.
Δ: Total score is 10 points or more and less than 20 points: The effect of giving a natural finish to dry skin is low.
X: Total score is less than 10 points: The effect of giving a natural finish to dry skin is very low.

In Examples 1 to 5, all the samples had a moisturizing feeling, had no squeaky skin, and were able to give the skin a natural finish even on dry skin.
On the other hand, sufficient effects were not obtained for Comparative Examples 1 to 3.
That is, in Comparative Example 1, since the component (A) was not contained, it could not be said that it was sufficient in terms of moisturizing feeling, no squeaky skin, and natural finish of dry skin.
In Comparative Example 2, since a component different from the component (A) was used, it could not be said that it was sufficient in terms of moisturizing feeling and natural finish of dry skin.
In Comparative Example 3, since the component (C) was not contained, it could not be said that the skin was not squeaky and the natural finish of the dry skin was not sufficient.

The following is an example of the formulation of the sunscreen composition according to the present invention.
[Pharmaceutical example 1] Sunscreen milk (% by mass)
Cyclopentasiloxane: 10
Hydrogenated polyisobutene (number average molecular weight: 1653): 1
Ethylhexyl methoxycinnamate: 7
t-Butylmethoxybenzoylmethane: 1
Hydrophobicized titanium oxide: 5
Hydrophobicized zinc oxide: 7
(VP / hexadecene) copolymer: 3
CERACUTE-L: 0.1
Glycerin: 6
BG: 0.6
Stearic acid: 2
PEG-10 Dimethicone: 4.5
Glyceryl oleate: 0.5
Magnesium sulfate: 0.5
Ethylhexyl glycerin: 0.2
Phenoxyethanol: 0.3
Sorbitan sesquiisostearate: 0.5
Fragrance: Appropriate amount Water: Remaining amount

[Pharmaceutical example 2] Sunscreen gel (% by mass)
Ethylhexyl palmitate: 1.5
Hydrogenated polyisobutene (number average molecular weight: 1653): 1
Olive fruit oil: 2
Dimethicone: 3
Ethylhexyl methoxycinnamate: 5.2
t-Butylmethoxydibenzoylmethane: 1.3
Hydrophobicized titanium oxide: 5
Hydrophobicized zinc oxide: 8
CERACUTE-L: 0.1
Polyquaternium-51: 0.01
Na hyaluronate: 0.01
Glycerin: 12
PEG-32: 2.5
BG: 8
(Acrylate / Alkyl Acrylate (C10-30)) Cross Polymer: 0.6
Pentylene glycol: 2.5
Phenoxyethanol: 0.5
Tocopherol: 0.01
Etidronic acid: 0.01
Sorbitan sesquiisostearate: 0.5
Polysorbate 60: 0.02
Potassium hydroxide: 0.12
Fragrance: Appropriate amount Water: Remaining amount

The sunscreen composition of the present invention can be applied to the skin such as the face and skin, and has a unique effect that cannot be obtained by the conventional sunscreen composition, specifically, a sufficient moisturizing feeling even on dry skin. Since it can achieve both the effect of obtaining no squeaky skin and the effect of finishing natural skin even on dry skin, it can be expected to be widely applied to sunscreen compositions.

Claims (1)

A sunscreen composition comprising 0.01 to 0.5% by mass of the component (A), 5 to 40% by mass of the component (B), and 0.1 to 10% by mass of the component (C).
Component (A): Contains a structural unit represented by the following formula (I) and a structural unit represented by the following formula (II), and the molar ratio (I / II) of both constituent units is 90/10 or more. 30/70 (meth) acrylic copolymer

(In the formula, R ¹ represents a hydrogen atom or a methyl group, R ² represents-(CH ₂ ) n-, n is an integer of 1 to 4. * represents a binding site with another constituent unit. .)

(In the formula, R ³ represents a hydrogen atom or a methyl group, and L ¹ is phenylene, cyclohexylene, -C (= O) -O-, -O-, -C (= O) -NH-, -O-. It represents C (= O)-or-OC (= O) -O-, L ² represents a linear or branched alkyl group having 10 to 22 carbon atoms, and * represents a binding site with another structural unit. Represents.)
Component (B): Ultraviolet scattering agent Component (C): Hydrogenated polyisobutene having a number average molecular weight of 100 to 3000