KR20210036837A - Sunscreen composition containing cerium oxide flake and inorganic uv-screening agent particle - Google Patents

Abstract

Disclosed is a sunscreen composition comprising cerium oxide (CeO_2) flakes having a hexagonal plate shape and inorganic sunscreen particles. The cerium oxide flakes having a hexagonal plate shape can be arranged to form a dense layer when the sunscreen composition containing the same is thinly applied to the skin, and thus can minimize gaps for ultraviolet rays to penetrate into the skin and scatter and reflect the ultraviolet rays. In this case, the inorganic sunscreen particles block the gaps present in the layer formed by the cerium oxide flakes, thereby synergistically increasing the UV blocking effect.

Description

Sunscreen composition comprising cerium oxide flakes and inorganic sunscreen particles {SUNSCREEN COMPOSITION CONTAINING CERIUM OXIDE FLAKE AND INORGANIC UV-SCREENING AGENT PARTICLE}

The present invention relates to a sunscreen composition comprising cerium oxide flakes and an inorganic sunscreen.

Sunscreens have been used for the purpose of reducing skin damage caused by photons emitted from sunlight and artificial light. Representative types of skin damage include sunburn exposed to the epidermal layer by UVB and sun aging exposed to the dermal layer by UVA. In the past,'sunscreen' was applied to the skin during outdoor activities as a sunscreen to reduce sunburn, but recently, cosmetics including sunscreen are applied to the skin for beauty purposes throughout daily life. UVB is attenuated as it passes through the glass, but UVA cannot be blocked by a window, so you can experience sun aging due to exposure to ultraviolet rays even inside a car or indoors. In other words, as it may be exposed to sun aging without distinguishing between indoors and outdoors, applying a cosmetic material containing an ultraviolet ray blocker at all times may be a way to protect the skin. For effective sun protection, two cases of synergy between the blocking performance of the sunscreen itself and the blocking power of the formulation can be considered, and it is desirable to consider skin troubles and potential harmfulness when used in cosmetics.

Sunscreens can be broadly classified into inorganic and organic sunscreens, and each blocker component has a blending limit set by the Ministry of Food and Drug Safety. Considering the blending limit of sunscreens, organic sunscreens may have higher potential human hazards such as skin troubles than inorganic sunscreens. Therefore, research on the technology of manufacturing UV-blocking cosmetics by using inorganic blockers more efficiently than organic blockers is emerging as a big task.

Inorganic UV blocking agents include titanium dioxide, zinc oxide, and cerium oxide, and in the case of titanium dioxide and zinc oxide, many formulation studies have been conducted and many formulations are commercially available. And it is not being widely used. Cerium oxide particles are basically inorganic sunscreens that have a hydrophilic surface, so they can be added to the water phase, but since the stiff powder texture and feeling of use are bad, it is common that oil-based acids have been made through hydrophobic surface treatment. In the case of including a hydrophobic surface treatment process separately, it is uneconomical, and for the development of a formulation for the presence of a UV-blocking active ingredient in the aqueous phase and the oil phase, the development of a technology for manufacturing a sunscreen containing a cerium oxide inorganic sunscreen in the aqueous phase. Has been required.

Accordingly, the inventors of the present invention were researching to solve the above problems, but using plate-shaped cerium oxide flakes instead of spherical cerium oxide particles as a sunscreen composition together with inorganic sunscreen particles, the two active ingredients for blocking ultraviolet rays are It was found to act synergistically and the present invention was completed.

In this regard, Korean Patent Registration No. 10-1600058 discloses a metal oxide complex high-flat cellulose powder and a cosmetic material containing the same.

_{The present invention provides a sunscreen composition comprising cerium oxide (CeO 2} ) flakes and inorganic sunscreen particles having a hexagonal plate shape as conceived to solve the above-described problem.

The technical problem to be achieved by the present invention is not limited to the technical problems mentioned above, and other technical problems that are not mentioned can be clearly understood by those of ordinary skill in the technical field to which the present invention belongs from the following description. There will be.

As a technical means for achieving the above-described technical problem, one aspect of the present invention,

_{It provides a sunscreen composition comprising cerium oxide (CeO 2} ) flakes and inorganic sunscreen particles having a hexagonal plate shape.

The inorganic sunscreen particles may be at least one selected from the group consisting of titanium oxide particles, zinc oxide particles, and cerium oxide particles.

The inorganic sunscreen particles may be included in an amount of 5 to 20 parts by weight based on 100 parts by weight of the sunscreen composition.

The inorganic sunscreen particles may be present in the oil phase.

The cerium oxide flake may be present in an aqueous or oil phase.

The cerium oxide flakes are present in the aqueous phase, the aqueous phase medium includes glutamic acid or aspartic acid, and the aqueous phase may have a pH of 3 to 6.

The cerium oxide flakes are present in the aqueous phase, and the cerium oxide flakes may be surface-modified by polyacrylic acid.

The aqueous phase may have a pH of 7.5 to 8.3.

The cerium oxide flakes are present in the oil phase, and the cerium oxide (CeO ₂ ) flakes are saturated fatty acids having 10 to 30 carbon atoms, unsaturated fatty acids having 10 to 30 carbon atoms, triethoxycaprylylsilane or polyhydroxystearic acid. It may be surface-modified with (polyhydroxystearic acid).

The oily solvent is alkyl benzoate, acetone, isopropyl alcohol, ethyl alcohol, ethyl ether, methylene chloride, xylene, glycerol, chloroform, dimethylformamide, nitrobenzene, methyl ethyl ketone, ethylene glycol, diethylene glycol. It may include a material selected from the group consisting of lycol, propylene glycol, dipropylene glycol, butylene glycol, ester oil, mineral oil, silicone oil, and combinations thereof.

The cerium oxide flake may have an average particle diameter of 0.5 µm to 30 µm.

The cerium oxide flake may have a hexagonal plate shape having an upper surface and a lower surface of a hexagonal shape.

The three pairs of sides facing each other in the hexagon each form an angle within 15° of each other,

When the length of the longest diagonal line is m and h is the height of the hexagonal plate among the three diagonal lines connecting opposite angles in the hexagon, m/h may be 2.5 to 1,500.

When the length of the longest diagonal line is m and the length of the shortest diagonal line is n among the three diagonal lines connecting opposite angles in the hexagon, m/n may be 1 to 250.

According to an embodiment of the present invention, the sunscreen composition of the present application synergistically exhibits a sunscreen effect by including a combination of cerium oxide flakes having a hexagonal plate shape and inorganic sunscreen particles as an active ingredient for sunscreen. Specifically, cerium oxide having a hexagonal plate shape can be arranged to form a dense layer when a sunscreen composition containing the same is applied to the skin thinly, thereby minimizing the gap for penetration of ultraviolet rays into the skin to scatter and reflect ultraviolet rays. I can make it. In this case, the inorganic UV blocking agent particles can synergistically increase the UV blocking effect by blocking the gap existing in the layer formed by the cerium oxide flake.

In addition, the hexagonal plate-shaped cerium oxide flake has a property of absorbing not only ultraviolet light, but also blue light, visible light, and near-infrared (IR) light. Can be very effective because it can block light in a wider wavelength band.

Furthermore, since the sunscreen composition according to an embodiment of the present invention has a low light refractive index of flakes, when applied to the skin, white turbidity does not occur, and thus it can be used as a sunscreen cosmetic composition showing a natural color.

The effects of the present invention are not limited to the above effects, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

1 is a schematic diagram showing the shape of a cerium oxide flake according to an embodiment of the present invention.
2 is a SEM photograph showing cerium oxide flakes having an average particle diameter of 5 μm according to an embodiment of the present invention.
3 is a SEM photograph showing cerium oxide flakes having an average particle diameter of 10 μm according to an embodiment of the present invention.
4 is a SEM photograph showing cerium oxide flakes having an average particle diameter of 20 μm according to an embodiment of the present invention.

Hereinafter, the present invention will be described in more detail. However, the present invention may be implemented in various different forms, and the present invention is not limited by the embodiments described herein, and the present invention is only defined by the claims to be described later.

In addition, terms used in the present invention are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the entire specification of the present invention, "including" a certain component means that other components may be further included, rather than excluding other components unless specifically stated to the contrary.

The first aspect of the present application,

_{It provides a sunscreen composition comprising cerium oxide (CeO 2} ) flakes and inorganic sunscreen particles having a hexagonal plate shape.

Hereinafter, the sunscreen composition according to the first aspect of the present application will be described in detail.

The sunscreen composition of the present application synergistically exhibits a sunscreen effect by including a combination of cerium oxide flakes having a hexagonal plate shape and inorganic sunscreen particles as an active ingredient for sunscreen. Specifically, cerium oxide having a hexagonal plate shape can be arranged to form a dense layer when a sunscreen composition containing the same is applied to the skin thinly, thereby minimizing the gap for penetration of ultraviolet rays into the skin to scatter and reflect ultraviolet rays. I can make it. In this case, the inorganic UV blocking agent particles can synergistically increase the UV blocking effect by blocking the gap existing in the layer formed by the cerium oxide flake.

The term “inorganic sunscreen particles” as used herein refers to particles of inorganic oxides having physical properties that reflect and disperse ultraviolet rays, and include particles such as titanium oxide, zinc oxide, iron oxide, and magnesium oxide, but are not limited thereto. Does not. Specifically, the inorganic sunscreen particles may be at least one selected from the group consisting of titanium oxide particles, zinc oxide particles, and cerium oxide particles.

In one embodiment of the present application, the content of the inorganic sunscreen particles may be 1 part by weight to 25 parts by weight, 2 parts by weight to 23 parts by weight, and preferably 5 parts by weight based on 100 parts by weight of the total sunscreen composition. It may be to 20 parts by weight. In this case, the content ratio of the inorganic sunscreen agent may be used without particular limitation according to the purpose and use to be applied within a range that does not impair the effects of the present invention.

It is preferable that the size of the inorganic sunscreen particles is 5 to 300 nm, specifically 50 to 250 nm. Since the particle size is smaller than the median particle diameter of the cerium oxide flake, it serves to fill the fine gaps formed by the cerium oxide flake plate shape.

The inorganic sunscreen may be surface-modified with a saturated fatty acid having 10 to 30 carbon atoms, an unsaturated fatty acid having 10 to 30 carbon atoms, triethoxycaprylylsilane, or polyhydroxystearic acid.

In one embodiment of the present application, the unsaturated fatty acid having 10 to 30 carbon atoms may have a double bond number of 18:1 to 18:3 with respect to the carbon number.

In one embodiment of the present application, the unsaturated fatty acid having 10 to 30 carbon atoms is α-linolenic acid, linoleic acid, γ-linoleic acid, Dihomo-γ-linoleic acid (Dihomo -γ-linolenic acid), palmitoleic acid, vaccinic acid, oleic acid, trans-Elaidic acid, and combinations thereof It may contain fatty acids.

In one embodiment of the present application, the saturated fatty acid having 10 to 30 carbon atoms or unsaturated fatty acid having 10 to 30 carbon atoms is not limited to the types presented above, and includes all saturated or unsaturated fatty acids having a hydrocarbon ring having 10 to 30 carbon atoms. I can.

In one embodiment of the present application, the polyhydroxystearic acid may include a hydroxystearic acid repeating unit. At this time, the hydroxystearic acid may have a structure represented by the following formula (1).

[Formula 1]

In one embodiment of the present application, the hydroxystearic acid repeating unit may have a structure represented by the following formula (2).

[Formula 2]

That is, the polyhydroxystearic acid may be formed by dehydration polymerization of a hydroxy group and a carboxyl group between hydroxystearic acid monomers in a solvent such as xylene. In this case, the dehydration polymerization reaction may be performed at a high temperature of about 200°C.

In one embodiment of the present application, the polyhydroxystearic acid may have a weight average molecular weight of 1,000 g/mol to 100,000 g/mol. If the weight average molecular weight of the polyhydroxystearic acid is less than 1,000 g/mol, the dispersion stability of the sunscreen composition may be lowered due to insufficient particle surface treatment, and if it exceeds 100,000 g/mol, polyhydroxystearic acid compared to cerium oxide flakes Since the molecular weight of the acid increases, the UV blocking effect of the sunscreen composition may decrease.

In one embodiment of the present application, by surface modification of cerium oxide flakes with a fatty acid having a specific length of 10 to 30 carbon atoms, triethoxycaprylylsilane or polyhydroxystearic acid, excellent emulsification/dispersion phase-stability in oily solvents And can have excellent application properties. When surface modification is performed with a fatty acid having 10 to 30 carbon atoms, triethoxycaprylylsilane, or polyhydroxystearic acid, emulsification in an oily solvent is smooth and dispersion stability of the formulation may be excellent.

In one embodiment of the present application, the content of the saturated fatty acid, unsaturated fatty acid, triethoxycaprylylsilane, or polyhydroxystearic acid is from 0.3 parts by weight to 15 parts by weight based on 100 parts by weight _{of surface-modified cerium oxide (CeO 2) flakes.} It may be parts by weight, 0.5 parts by weight to 11 parts by weight, preferably 1 part by weight to 10 parts by weight. When the content of the saturated fatty acid, unsaturated fatty acid, or polyhydroxystearic acid is surface-modified to less than 0.3 parts by weight, the entire surface of the cerium oxide flakes is not surface-modified, and thus emulsification/dispersion problems may occur during production with a solvent. In addition, when the content of the saturated fatty acid, unsaturated fatty acid, triethoxycaprylylsilane, or polyhydroxystearic acid is modified in excess of 15 parts by weight, excess molecules surrounding the flake surface are scattered and impurities in the manufacture of cosmetics. Can act as Furthermore, if the content of the fatty acid is too small, the surface of the flakes cannot be sufficiently covered, and if there is too much, it is scattered with excess molecules and acts as an impurity during the manufacture of cosmetics, which may lead to rancidity of the cosmetics, and excessive oiliness inhibits the feeling of use. I can make it.

In one embodiment of the present application, the inorganic sunscreen particles may exist in an aqueous or oil phase, but preferably may exist in an oil phase. In one embodiment of the present application, the oily solvent is alkyl benzoate, acetone, isopropyl alcohol, ethyl alcohol, ethyl ether, methylene chloride, xylene, glycerol, chloroform, dimethylformamide, nitrobenzene, methyl ethyl ketone, ethylene. Including a substance selected from the group consisting of glycol, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, ester oil, mineral oil, silicone oil, and combinations thereof Can be.

In one embodiment of the present application, the silicone oil may be dimethicone, cetyl dimethicone, cyclopentasiloxane, cyclohexasiloxane, stearyl dimethicone, or the like.

In one embodiment of the present application, the saturated fatty acid having 10 to 30 carbon atoms is capric acid, undecyl acid, lauric acid, tridecylic acid, myristic Myristic acid, Palmitic acid, Margaric acid, Stearic acid, Nonadecylic acid, Arachidic acid, Heneicosanoic acid ), Behenic acid, Tricosanoic acid, Lignoceric acid, Pentacosanoic acid, Ceotic acid, Heptacosanoic acid, Montanic acid It may include a fatty acid selected from the group consisting of (Montanic acid), Nonacosanoic acid, Melisic acid, and combinations thereof.

Cerium oxide flakes may be present in an aqueous or oil phase. When the cerium oxide flakes are present in the aqueous phase and the inorganic sunscreen particles are present in the oil phase, the two active ingredients of the two sunscreen agents may stably exist in different phases, as well as complementary and complementary sunscreen effects.

The aqueous medium in which the cerium oxide flakes are dispersed may be purified water, and may be acidic water having a pH of 5 to 7. The content of the aqueous phase can be freely selected within the range as described above according to the formulation of the sunscreen composition to be prepared. For example, in the case of manufacturing a creamy water-in-oil (O/W) sunscreen composition with a lot of oil, the content of the aqueous phase is lowered and the content of the oil phase is increased to form an emulsion in which the discontinuous phase, which is a continuous phase, is dispersed. In the case of manufacturing an oil-in-water (W/O) sunscreen cosmetic composition in the form of a lot of moisture, it is an emulsion in which the oil phase, which is a discontinuous phase, is dispersed in the water phase, which is a continuous phase, by increasing the content of the water phase and lowering the oil phase. It can also be manufactured with. Specifically, the aqueous medium may be included in an amount of 20 to 80% by weight based on the total composition, and more specifically, may be included in an amount of 30 to 40% by weight.

The cerium oxide flakes of the present application are easily dispersed under the aqueous phase medium, but the aqueous phase medium may include one or more additives in order to increase water dispersibility.

According to one embodiment of the present application, the aqueous medium includes a pH adjusting agent, and may have an acidic pH, specifically a pH of 3 to 6, and more specifically, a pH of 4.5 to 5.5. In this case, the cerium oxide flakes are in a state of having a positive charge on the surface in the aqueous phase, and thus dispersibility may be increased. The aqueous medium may include an acidic amino acid or a derivative thereof. The acidic amino acid or derivative thereof may be represented by the following formula (3).

[Formula 3]

In Formula 3, X represents H or an acyl group of _{C 1-6.} The acyl group of C _{1-6 represents} a group in which one hydrogen atom is substituted with a carbonyl group in an alkyl group having 1 to 6 carbon atoms, and specifically, an acetyl group, a propionyl group, a butyryl group, and the like may be included. When the hydrophobicity of the acyl group is too high, it is not suitable for dispersion of cerium oxide flakes in the aqueous phase.

In Formula 3, n represents an integer of 1 to 3, and may preferably be 1 or 2.

In Formula 3, Y and Z are each independently an ester-forming residue of _{H or C 1-6 alcohol.} Alcohol of C _{1-6 represents} a group in which one hydrogen atom is substituted with a hydroxy group in an alkyl group having 1 to 6 carbon atoms. At least one of Y and Z is preferably hydrogen in terms of increasing the acidity of the aqueous phase. When the hydrophobicity of the alcohol is too high, it is not suitable for dispersion of cerium oxide flakes in the aqueous phase.

The acidic amino acid or derivative thereof may be isolated from nature or may be chemically synthesized.

The amino acid may be glutamic acid or aspartic acid.

The amino acid or a derivative thereof may be L-type or D-type.

According to one embodiment of the present application, the cerium oxide flake may be treated with a hydrophilic surface modifier such as acrylic acid, methacrylic acid, isobutyl acrylamide or poly N-substituted isopropyl acrylamide in order to increase water dispersibility.

Specifically, the hydrophilic surface modifier may be a polycarboxylic acid represented by the following formula (4).

[Formula 4]

In Formula 4, R ₁ and R ₂ may each independently be hydrogen, C _1-4 alkyl, C _2-4 alkenyl, or C _2-4 alkynyl.

R ₃ is hydrogen or -COOM, and M is hydrogen or an alkali metal. _{-The higher the ratio of R 3} , which is COOM, the higher the negative charge property of the surface-modified cerium oxide flakes. In order to control the size and dispersibility of the cerium oxide flakes, _{the ratio of R 3} , which is -COOM, can be adjusted.

n is 10 to 60, and if it is out of the above range, the dispersibility of the flakes may deteriorate.

The cerium oxide flakes added for the UV blocking effect herein may be provided as an aqueous phase having high dispersibility as the cerium oxide flakes are modified by the polycarboxylic acid.

According to the exemplary embodiment of the present disclosure, when the aqueous phase in which cerium oxide flakes are water-dispersed has an appropriate level of basicity, it may have excellent dispersibility of particles. Specifically, the pH of the aqueous phase may be 7.5 to 8.3, more specifically 7.7 to 8.2. When the pH of the aqueous phase is lower than this, the cerium oxide flakes do not sufficiently exhibit negative charges on the surface, and thus the dispersibility may decrease. If the pH of the aqueous phase is higher than this, it becomes difficult to apply to the skin due to its high acidity.

According to the exemplary embodiment of the present disclosure, the aqueous medium may further include any one or more selected from the group consisting of a lower alcohol, a polyhydric alcohol, a moisturizing agent, and a pH adjusting agent.

In one embodiment of the present application, the lower alcohol may be, for example, ethanol, propanol, isopropanol, isobutyl alcohol, t-butyl alcohol, and the like. In addition, the polyhydric alcohol is, for example, a dihydric alcohol (eg, ethylene glycol, propylene glycol, trimethylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, tetramethylene glycol, 2,3-butyl Ethylene glycol, pentamethylene glycol, 2-butylene-1,4-diol, hexylene glycol, octylene glycol, etc.); Trihydric alcohols (eg glycerin, trimethylolpropane, etc.); And the like.

In one embodiment of the present application, the moisturizing agent is, for example, polyethylene glycol, propylene glycol, glycerin, 1,3-butylene glycol, xylitol, sorbitol, maltitol, chondroitin sulfuric acid, hyaluronic acid, mucoitin sulfuric acid, caronic acid, Atherocollagen, cholesterol-12-hydroxystearate, sodium lactate, bile salt, dl-pyrrolidone carboxylate, short chain soluble collagen, diglycerin (EO)PO adduct, Rosa roxburghii extract, Yarrow extract, marirod extract, and the like. In addition, the pH adjusting agent is, for example, a buffer such as lactic acid-sodium lactate, citric acid-sodium citrate, succinic acid-sodium succinate, and organic amines such as monoethanolamine, diethanolamine, triethanolamine, and tromethamine. Can be used.

In one embodiment of the present application, the content of the combined component of the lower alcohol, polyhydric alcohol, moisturizer and pH adjuster is not particularly limited within a range that does not impair the effect of the present invention, and 5 parts by weight based on 100 parts by weight of the sunscreen composition To 25 parts by weight, preferably 10 to 20 parts by weight, more preferably 12 to 18 parts by weight may be included.

Cerium oxide flakes may exist in the oil phase together with inorganic sunscreen particles, and these components maximize dispersion due to the mutual presence of the inorganic sunscreen particles, so that the sunscreen effect can be effectively exhibited.

At this time, the cerium oxide (CeO ₂ ) flakes oil-dispersed in the oily solvent surface with the aforementioned saturated fatty acid having 10 to 30 carbon atoms, unsaturated fatty acid having 10 to 30 carbon atoms, triethoxycaprylylsilane or polyhydroxystearic acid. It may be characterized by being modified.

In one embodiment of the present application, the cerium oxide flake may have an average particle diameter of 0.5 µm to 30 µm. If the average particle diameter of the cerium oxide flakes is less than 0.5 μm, the size may be too small to reduce the effect of blocking blue light and infrared rays, and if it exceeds 30 μm, the size may be too large and may not be well mixed when used as a sunscreen composition. More preferably, the cerium oxide flake may have an average particle diameter of 5 μm to 20 μm. In addition, the cerium oxide flake may have an average thickness of 20 nm to 290 nm, preferably 20 nm to 150 nm, and more preferably 20 nm to 100 nm. When the average thickness of the cerium oxide flakes exceeds 290 nm, the size of the cerium oxide flakes is too large to reduce the UV blocking effect. That is, the thinner the average thickness of the cerium oxide flakes, the better the UV blocking effect may be, and the preferable thickness range may be as described above. The average particle diameter may be a median particle diameter measured by a scanning electron microscope or a laser diffraction method.

In one embodiment of the present application, the cerium oxide flake may be characterized in that it has absorbance in a wavelength range of 290 nm to 1,500 nm, and when the cerium oxide flake is dispersed in an aqueous medium, the concentration of the cerium oxide flake May be characterized by having an _{absorbance of 1.0 or more (λ max} = 350 nm) under the condition of 0.05% by weight. That is, the sunscreen composition including the cerium oxide flake may have a property of absorbing light in a wide wavelength range from a wavelength in an ultraviolet region to a wavelength in a near infrared region. More specifically, the sunscreen composition comprising the cerium oxide flake _{has an absorbance of 0.3 or more at a concentration of 0.01% by weight based on λ max} 350 nm, an absorbance of 1.5 or more at a concentration of 0.03% by weight, and 2.0 or more at a concentration of 0.05% by weight. It may have absorbance. In addition, in the wavelength range of 400 nm to 900 nm, it may have an absorbance of 0.2 or more at a concentration of 0.01% by weight, an absorbance of 1.0 or more at a concentration of 0.03% by weight, and an absorbance of 1.5 or more at a concentration of 0.05% by weight. Therefore, the cerium oxide flake has a property of absorbing not only ultraviolet light, but also light of blue light, visible light, and near-infrared light, so when used as a sunscreen composition, it has a wider wavelength than the conventional sunscreen composition. It can be very effective because it can block light in the band.

The term “hexagonal plate shape” as used herein refers to a hexagonal plate shape having an upper surface and a lower surface of a hexagonal shape.

In one embodiment of the present application, the three pairs of sides facing each other in the hexagon may each form an angle within 15° to each other, and preferably form an angle within 10°. That is, the cerium oxide flakes are almost parallel because the three pairs of sides facing each other in the hexagonal shape of the upper and lower surfaces form an angle within 15° of each other, and the diagonals of the three pairs of the inside of the hexagon are each approximately the same angle. It may be to have. When any one or more of the three pairs of sides facing each other in the hexagon form an angle of more than 15°, the absorbance of the cerium oxide flake may be lowered, and the sunscreen composition including the same may not exhibit a certain light absorption property. I can.

In one embodiment of the present application, m/h is 2.5 to 1,500 when the length of the longest diagonal line is m and the height of the hexagonal plate is h among the three diagonal lines connecting the angles facing each other in the hexagon. It may be, and preferably the m/h may be 10 to 250. As the m/h is 2.5 to 1,500, the cerium oxide flake may have a flat hexagonal plate shape because the height of the hexagonal plate is relatively short compared to the length of the longest diagonal line of the upper and lower surfaces of the hexagonal shape. Accordingly, the cerium oxide flake may have excellent light absorption characteristics in a wide wavelength range of 290 nm to 1,500 nm. In this regard, when the m/h is less than 2.5, the cerium oxide flakes become thick, so that the light absorption characteristics are deteriorated, and when the cerium oxide flake is used as a sunscreen composition, application properties may be deteriorated.

In one embodiment of the present application, m/n is 1 to 250 when the length of the longest diagonal line is m and n is the length of the shortest diagonal line among the three diagonal lines connecting opposite angles in the hexagon. It may be, and preferably, it may be characterized in that it is 2 to 250. Accordingly, the hexagon may have a long hexagonal shape other than a regular hexagon, and thus the cerium oxide flake may also have a long hexagonal plate shape. On the other hand, when m/n is 1, since it has a regular hexagonal plate shape, absorbance for light may also decrease.

In one embodiment of the present application, the cerium oxide flake is cerium hydroxide, cerium oxide, cerium carbonate, cerium nitrate, cerium chloride , Ammonium cerium nitrate, and a material selected from the group consisting of combinations thereof.

In one embodiment of the present application, the sunscreen composition may include an emulsifier. The emulsifier may be used without any particular kind of limitation as long as it is an emulsifier capable of forming an emulsion-type formulation by properly mixing an aqueous phase and an oily raw material within a range that does not impair the effects of the present invention. An ionic emulsifier, a cationic emulsifier or an anionic emulsifier may be used, and more preferably a nonionic emulsifier may be used.

In one embodiment of the present application, the content of the emulsifier may be 1 part by weight to 10 parts by weight, preferably 0.1 part by weight to 7 parts by weight, and more preferably 1 part by weight based on 100 parts by weight of the sunscreen composition. It may be from parts to 5 parts by weight. When the content of the emulsifier is less than 1 part by weight, it may be difficult to form an emulsion because the amount of the emulsifier is too small, and when the amount of the emulsifier is more than 5 parts by weight, the amount of the emulsifier is too large, and the feeling of use may be impaired.

In one embodiment of the present application, the sunscreen composition may further include a cosmetic formulation composition.

In one embodiment of the present application, the cosmetic formulation composition is oils, waxes, surfactants, thickeners, pigments, cosmetic additives, powders, sugars, antioxidants, buffers, various extracts, stable within the range that does not impair the effects of the present invention. Ingredients commonly blended in cosmetic compositions such as an agent, an irritation reliever, a preservative, a moisturizer, and a fragrance may be appropriately blended and used.

In one embodiment of the present application, the fats and oils include vegetable oils such as moonshine colostrum oil, rosehip oil, castor oil or olive oil, animal oils such as mink oil or squalene, mineral oils such as liquid paraffin or petrolatum, silicone oil, or myristine. Synthetic oils such as isopropyl acid may be used.

In one embodiment of the present application, as the waxes, vegetable waxes such as carnauba wax, candelilla wax or jojoba oil, and animal waxes such as beeswax or lanolin may be used.

In one embodiment of the present application, as the surfactant, an anionic surfactant, a cationic surfactant, an amphoteric surfactant or a nonionic surfactant may be used.

In one embodiment of the present application, the dye may be, for example, a synthetic or natural dye, and the synthetic dye may be a water-soluble/soluble dye such as FD&C Yellow No 6 or FD&C Red No 4, iron oxide or ultramarine. Inorganic pigments, organic pigments such as D&C Red No 30 or D&C Red No 36, lakes such as FD&C Yellow No 6 Al lake, etc. can be used. Carotenoid pigments such as pin, capxanthine, vichycin, crocin, or candaxanthin, flavonoid pigments such as sisonine, lamanin, niacin, carsamine, saprole yellow, rutin, guelcetin, or cacao pigment, Flavin pigments such as riboflavin, quinone pigments such as lacaphosphoric acid, carmic acid (cokinyl), kermesic acid, arizarine, sicorine, arganine or nikinochrome, porphyrin pigments such as chlorophyll or hemoglobin, Diketone-based pigments such as crcmine (dameric), beta-cyanidin-based pigments such as betanin, and the like may be used.

In one embodiment of the present application, the cosmetic additive may be, for example, vitamins, plant extracts or animal extracts, and the vitamins include retinol (vitamin A), tocopherol (vitamin E), or ascorbic acid (vitamin X). The plant extract may be menthol (mint), azulene (chamomile), allantoin (wheat), caffeine (coffee), licorice extract, cinnamon extract, green tea extract, lavender extract, lemon extract, etc., and the like. Animal extracts may include placenta (bovine placenta), royal jelly (bee secretions), snail extract (mucus secretions), and the like.

Hereinafter, embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

Example 1. Preparation of a sunscreen composition comprising cerium oxide flakes (average particle diameter 5 μm) and inorganic sunscreen particles (Titanium dioxide)

Step 1: Preparation of cerium oxide flakes (average particle diameter 5 μm)

In order to prepare cerium oxide flakes having an average particle diameter of 5 μm, 100 parts by weight of cerium nitrate was first added to 600 parts by weight of purified water, followed by stirring. Meanwhile, 100 parts by weight of triethanolamine, 100 parts by weight of urea, and 10 parts by weight of ethylene glycol were added to 1,000 parts by weight of purified water, followed by stirring. After mixing each of the stirred solutions, reacted for 4 hours in a 80 ℃ water bath to synthesize cerium oxide flakes. The synthesized cerium oxide flakes were centrifuged several times to remove unreacted products, and then dried in an oven to obtain cerium oxide flakes in powder form. Then, the obtained cerium oxide flakes in powder form were calcined at 450° C. for 2 hours in an air atmosphere to prepare cerium oxide flake powder from which impurities were removed. At this time, SEM photographs of the prepared cerium oxide flake powder are shown in FIGS. 2A and 2B, respectively. The diameter of the prepared cerium oxide flake powder was 2 μm to 7 μm as shown in FIG. 2A, and the thickness was 20 nm to 100 nm as shown in FIG. 2B.

Step 2: Preparation of sunscreen composition

In order to prepare a sunscreen composition comprising cerium oxide flakes and an inorganic sunscreen agent having an average particle diameter of 5 μm prepared in step 1, a sunscreen composition was prepared by mixing at the composition ratio shown in Table 1 below. Specifically, after stirring each of the A phase (oil phase) and B phase (aqueous phase), the B phase was slowly added to the A phase and stirred to prepare a sunscreen composition. At this time, the stirring speed was 400 rpm, and the stirring time was 10 minutes.

phase ingredients INCI weight% A
(oil phase) ABIL EM 90 Cetyl PEG/PPG-10/1 Dimethicone 3 Cyclomethicone Cyclomethicone 19 Bentone gel ISDV Isododecane 3 Dermofeel bgc Butylene Glycol Dicaprylate/Dicaprate 5.5 Titanium Dioxide Titanium Dioxide 10 B
(water phase) Cerium oxide flake Cerium oxide 10 1,3-Butylene glycol 1,3-Butylene glycol 5 Ethylhexylglycerine Ethylhexylglycerine 0.05 Phenoxyethanol Phenoxyethanol 0.5 Dipropyleneglycol Dipropyleneglycol 6 Water Water 37.95 Total 100

Example 2. Preparation of a sunscreen composition comprising cerium oxide flakes (average particle diameter 5 μm) and inorganic sunscreen particles (Zinc dioxide)

Step 1: Preparation of cerium oxide flakes (average particle diameter 5 μm)

In order to prepare cerium oxide flakes having an average particle diameter of 5 μm, 100 parts by weight of cerium nitrate was first added to 600 parts by weight of purified water, followed by stirring. Meanwhile, 100 parts by weight of triethanolamine, 100 parts by weight of urea, and 10 parts by weight of ethylene glycol were added to 1,000 parts by weight of purified water, followed by stirring. After mixing each of the stirred solutions, reacted for 4 hours in a 80 ℃ water bath to synthesize cerium oxide flakes. The synthesized cerium oxide flakes were centrifuged several times to remove unreacted products, and then dried in an oven to obtain cerium oxide flakes in powder form. Then, the obtained cerium oxide flakes in powder form were calcined at 450° C. for 2 hours in an air atmosphere to prepare cerium oxide flake powder from which impurities were removed. At this time, SEM photographs of the prepared cerium oxide flake powder are shown in FIGS. 2A and 2B, respectively. The diameter of the prepared cerium oxide flake powder was 2 μm to 7 μm as shown in FIG. 2A, and the thickness was 20 nm to 100 nm as shown in FIG. 2B.

Step 2: Preparation of sunscreen composition

In order to prepare a sunscreen composition comprising cerium oxide flakes and an inorganic sunscreen agent having an average particle diameter of 5 μm prepared in step 1, a sunscreen composition was prepared by mixing in the composition ratio shown in Table 2 below. Specifically, after stirring each of the A phase (oil phase) and B phase (aqueous phase), the B phase was slowly added to the A phase and stirred to prepare a sunscreen composition. At this time, the stirring speed was 400 rpm, and the stirring time was 10 minutes.

phase ingredients INCI weight% A
(oil phase) ABIL EM 90 Cetyl PEG/PPG-10/1 Dimethicone 3 Cyclomethicone Cyclomethicone 19 Bentone gel ISDV Isododecane 3 Dermofeel bgc Butylene Glycol Dicaprylate/Dicaprate 5.5 Zinc Dioxide Zinc Dioxide 10 B
(water phase) Cerium oxide flake Cerium oxide 10 1,3-Butylene glycol 1,3-Butylene glycol 5 Ethylhexylglycerine Ethylhexylglycerine 0.05 Phenoxyethanol Phenoxyethanol 0.5 Dipropyleneglycol Dipropyleneglycol 6 Water Water 37.95 Total 100

Comparative Example 1. A composition containing only titanium dioxide, not containing cerium oxide flakes

It was prepared in the same manner as in Example 1, but a sunscreen composition was prepared in the composition of Table 3 below.

phase ingredients INCI weight% A
(oil phase) ABIL EM 90 Cetyl PEG/PPG-10/1 Dimethicone 3 Cyclomethicone Cyclomethicone 19 Bentone gel ISDV Isododecane 3 Dermofeel bgc Butylene Glycol Dicaprylate/Dicaprate 5.5 Titanium Dioxide Titanium Dioxide 10 B
(water phase) Cerium oxide flake Cerium oxide - 1,3-Butylene glycol 1,3-Butylene glycol 5 Ethylhexylglycerine Ethylhexylglycerine 0.05 Phenoxyethanol Phenoxyethanol 0.5 Dipropyleneglycol Dipropyleneglycol 6 Water Water 47.95 Total 100

Comparative Example 2. A composition that does not contain cerium oxide flakes, but contains only inorganic substances (Zinc Dioxide)

It was prepared in the same manner as in Example 2, but a sunscreen composition was prepared in the composition of Table 4 below.

phase ingredients INCI weight% A
(oil phase) ABIL EM 90 Cetyl PEG/PPG-10/1 Dimethicone 3 Cyclomethicone Cyclomethicone 19 Bentone gel ISDV Isododecane 3 Dermofeel bgc Butylene Glycol Dicaprylate/Dicaprate 5.5 Zinc Dioxide Zinc Dioxide 10 B
(water phase) Cerium oxide flake Cerium oxide 10 1,3-Butylene glycol 1,3-Butylene glycol 5 Ethylhexylglycerine Ethylhexylglycerine 0.05 Phenoxyethanol Phenoxyethanol 0.5 Dipropyleneglycol Dipropyleneglycol 6 Water Water 47.95 Total 100

Experimental Example 1. UV blocking index and PA index measurement experiment

In order to measure the UV protection index (SPF) and PA index of the sunscreen compositions prepared in Examples 1, 2, Comparative Example 1, and Comparative Example 2, SPF and PA were measured using SPF analyzer 290S of Laser Componets, UK. It was measured, and the results are shown in Table 5 below.

Example 1 Example 2 Comparative Example 1 Comparative Example 2 CeO ₂ Flakes content (% by weight) 10% 10% - - Inorganic tea content (% by weight) 10% 10% 10% 10% SPF 59 57 16 14 PA 45 (++++) 43 (++++) 12 (+++) 10 (+++)

As can be seen in Table 5, it was confirmed that the UV protection composition including cerium oxide flakes and the inorganic UV protection agent each exhibited remarkably high SPF and PA values compared to the UV protection composition containing only the inorganic UV protection agent.

The above description of the present invention is for illustrative purposes only, and those of ordinary skill in the art to which the present invention pertains will be able to understand that other specific forms can be easily modified without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are illustrative in all respects and are not limiting. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as being distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the claims to be described later, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention.

Claims (14)

_{Cerium oxide (CeO 2} ) having a hexagonal plate shape, including flakes and inorganic sunscreen particles, a sunscreen composition.
The sunscreen composition of claim 1, wherein the inorganic sunscreen particles are at least one selected from the group consisting of titanium oxide particles, zinc oxide particles, and cerium oxide particles.
The sunscreen composition of claim 1, wherein the inorganic sunscreen particles are contained in an amount of 5 to 20 parts by weight based on 100 parts by weight of the sunscreen composition.
The sunscreen composition of claim 1, wherein the inorganic sunscreen particles are present in an oil phase.
The sunscreen composition of claim 4, wherein the cerium oxide flake is present in an aqueous or oil phase.
The sunscreen composition of claim 5, wherein the cerium oxide flakes are present in an aqueous phase, and the aqueous phase medium includes glutamic acid or aspartic acid, and the aqueous phase has a pH of 3 to 6.
The sunscreen composition of claim 5, wherein the cerium oxide flakes are present in an aqueous phase, and the cerium oxide flakes are surface-modified by polyacrylic acid.
The sunscreen composition of claim 7, wherein the aqueous phase has a pH of 7.5 to 8.3.
The method of claim 1, wherein the cerium oxide flakes are present in the oil phase, and the cerium oxide (CeO ₂ ) flakes are saturated fatty acids having 10 to 30 carbon atoms, unsaturated fatty acids having 10 to 30 carbon atoms, and triethoxycaprylylsilane. Or polyhydroxystearic acid (polyhydroxystearic acid) will be surface-modified, sunscreen composition.
The method of claim 2, wherein the oily solvent is alkyl benzoate, acetone, isopropyl alcohol, ethyl alcohol, ethyl ether, methylene chloride, xylene, glycerol, chloroform, dimethylformamide, nitrobenzene, methyl ethyl ketone, ethylene glycol. Containing a substance selected from the group consisting of lycol, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, ester oil, mineral oil, silicone oil, and combinations thereof Phosphorus, sunscreen composition.
The sunscreen composition of claim 1, wherein the cerium oxide flake has an average particle diameter of 0.5 µm to 30 µm.
The method of claim 1,
The cerium oxide flake is a sunscreen composition that has a hexagonal plate shape having an upper surface and a lower surface of a hexagonal shape.
The method of claim 12,
The three pairs of sides facing each other in the hexagon each form an angle within 15° of each other,
A sunscreen composition, wherein m/h is 2.5 to 1,500 when the length of the longest diagonal line is m and the height of the hexagonal plate is h among the three diagonal lines connecting opposite angles in the hexagon.
The method of claim 12,
When the length of the longest diagonal line is m and the length of the shortest diagonal line is n, m/n is 1 to 250 of the three diagonal lines connecting opposite angles in the hexagon.

Images