KR100845722B1 - Cosmetic Composition for Whitening the Skin Comprising Ledum palustre extracts as Active Ingredient - Google Patents

Abstract

The present invention provides a cosmetic composition for skin whitening containing white acid tea extract as an active ingredient. White acid tea extract of the present invention has an excellent effect of inhibiting tyrosinase activity, has a melanin production inhibitory effect on melanocytes, and does not irritate almost the skin, and thus may be usefully used as an active ingredient of a cosmetic composition for skin whitening having excellent stability. .

White tea, tyrosinase, melanin, whitening, cosmetic composition

Description

Cosmetic composition for skin whitening including white acid tea extract as an active ingredient {Cosmetic Composition for Whitening the Skin Comprising Ledum palustre extracts as Active Ingredient}

The present invention relates to a cosmetic composition for skin whitening comprising white acid tea extract as an active ingredient.

It is everyone's constant desire to have white, fair skin. In general, the color of human skin, hair and eyes is determined by melanin, carotene and hemoglobin and the like. In particular, melanin is the most important factor for determining the skin color, the skin color is determined according to the amount, nature and distribution of melanin. Human skin and hair pigments protect skin and hair from the harmful effects of sunlight, especially ultraviolet light. For example, people who lack these pigments are very sensitive to sunlight and are prone to burns and have a high probability of developing skin cancer even at a young age. Short wavelength ultraviolet (290-320 nm) and carcinogens form harmful radicals in the skin, such as oxygen radicals, which are known to attack skin cells and age the skin.

The main function of melanin is to remove these harmful radicals and protect the skin from the damage thereby. Therefore, high levels of melanin means that it has an effective response system that can protect the skin from physical or chemical toxic substances. Factors that promote the production of melanin include sunlight (ultraviolet rays) as well as estrogen or prostaglandin.

On the other hand, melanin is produced through the complex oxidation and condensation reaction of melanocytes in the melanocytes tyrosine is converted to dopa (DOPA), dopachrome by an enzyme called tyrosinase (tyrosinase). The produced melanin is delivered to the skin cells and exhibits a circulating action in which the melanin is lost due to epidermal detachment.

This melanin production process is a naturally occurring phenomenon, and overproduction of melanin does not occur in normal human skin. However, when the skin responds to external stimuli such as ultraviolet rays, environmental pollution or stress, excessive production of melanin. When the excessively produced melanin is not discharged out of the skin and remains in the skin, pigmentation occurs, resulting in blemishes and freckles.

Among the external stimulating factors, UV is the largest melanin biosynthetic stimulus, and may affect various processes related to melanin production. That is, ultraviolet rays act as an important factor inducing melanin overproduction by promoting the activity of melanocytes, melanocytes, melanin biosynthesis stimulating hormone secretion, melanin oxidation, or tyrosinase activity.

The most distinctive feature of the melanin production mechanism is that only one enzyme called tyrosinase is involved. When the tyrosinase activity is inhibited to prevent melanin production, a whitening effect can be expected.

In the prior art, it is known to use ascorbic acid as a whitening substance (Japanese Patent Laid-Open No. 4-9320). However, ascorbic acid is poor in phase stability in the formulation, there is a problem that the activity of the active ingredient is poor over time. Therefore, in recent years, various methods such as stabilizing ascorbic acid with capsules or liposomes have been proposed, but have not yet provided a clear stabilization method.

It is known to use hydroquinone as another whitening substance (Japanese Patent Laid-Open No. 6-192062). Hydroquinone has an excellent effect but is limited to its use as a cosmetic since it is a carcinogenic substance.

It is known to use kojic acid as another whitening substance (Japanese Patent Laid-Open No. 56-7710). Kojic acid has an excellent inhibitory ability of tyrosinase and thus shows an excellent whitening effect, but also has a problem in terms of safety in the formulation and has recently been announced as a carcinogen.

It is known to use arbutin as another whitening substance (Japanese Patent Laid-Open No. 4-9315). Arbutin can be extracted or synthesized from alpine bilberry and its ability to inhibit tyrosinase, like kojic acid, has been demonstrated. However, arbutin itself has a problem in that the sugar is attached to the hydroquinone, and when applied to the cosmetic, the sugar is separated by the skin enzyme to cause skin irritation by the hydroquinone.

In addition, in recent years, various cosmetic companies have been developing various research and development related to skin whitening, such as various kinds of whitening agents using natural products.However, there is no relation to the skin whitening effect of white acid tea extract or its use as a skin whitening agent. None known.

Throughout this specification, numerous patent documents and articles are referenced and their citations are indicated. The disclosures of cited patent documents and articles are incorporated herein by reference in their entirety, so that the level of the technical field to which the present invention belongs and the contents of the present invention are more clearly explained.

Accordingly, the present inventors have made intensive studies to overcome the problems of the conventional cosmetic composition for skin whitening, that is, lowering of stability, side effects of skin and weakening of the whitening effect, the white tea extract is excellent in tyrosinase activity inhibitory effect The present invention was completed by confirming that dopachrome automatic oxidation inhibitory effect and melanocyte production of melanocytes were inhibited and that there was no skin irritation.

Accordingly, it is an object of the present invention to provide a cosmetic composition for skin whitening comprising white acid tea extract as an active ingredient.

Other objects and advantages of the invention will be apparent from the following examples and claims.

The present invention provides a cosmetic composition for skin whitening comprising white acid extract as an active ingredient.

Baeksan tea extract containing an active ingredient in the cosmetic composition of the present invention is an extract extracted from Baeksan tea. Ledum palustre is a small shrub of 15-70cm in height and azalea and evergreen. It is a dicotyledonous plant that lives under the forests of high mountains in Korea, Japan, Ussuri River, Saharin Island and eastern Siberia. It is characterized by sprouting young shoots from roots and dense brown hairs on young branches. Leaves are alternate, long oval or lanceolate, 3-8cm long, 4-12mm wide, dark green, with many wrinkles. The back of the leaves is dense and fragrant with brown and white hairs, and the edges curl back. Flowers bloom in white in May-June, with flowering branches and hairs. Pau is egg-shaped, calyx and petals are 5, 10 stamens and 1 pistil. Fruits are capsules, long oval, ripen in September. The pharmacological action of Baishan tea is known as phlegm removal, cough relieving action and anti-inflammatory action of volatile components (Changbai Mountain medicinal plant coloring paper, People's Press, 1997).

As used herein, the term “baeksan tea extract” means obtained by extracting from various organs or parts (eg, leaves, flowers, roots, stems, branches, bark and seeds, etc.) of the white tea tree, preferably leaves, Stem, branch, bark or root, more preferably leaves, branches or roots, most preferably extracts obtained from leaves.

Preferably, the white tea extract in the present invention comprises (a) water, (b) anhydrous or hydrous lower alcohol having 1 to 4 carbon atoms (such as methanol, ethanol, propanol and butanol), (c) acetone, (d) ethyl A solvent selected from the group consisting of acetate, (e) chloroform, (f) butyl acetate, and (g) 1,3-butylene glycol was obtained from the leaves of white tea, etc. as an extraction solvent. The extraction solvent is preferably a hydrous lower alcohol, more preferably 70-95% alcohol and most preferably 70% alcohol. A suitable amount of the extraction solvent is 1-20 times the dry weight of the white tea leaf, more preferably 1-10 times.

 According to a specific embodiment of the present invention, the extraction is carried out as follows. First, the white tea leaves are washed with purified water, dried and broken into small pieces, and then, the extractant of 1-10 times the dry weight is added thereto. After cooling condenser is installed to prevent the active ingredient from evaporating in the state of extraction for 3 to 20 hours by heating at 40-100 ℃, or extract for 1 to 15 days at 4-40 ℃ and prepared by completely drying with a rotary vacuum evaporator . In this case, 1,3-butylene glycol is difficult to dry by using a rotary vacuum evaporator, so it is manufactured by adjusting the drying loss to 1% (w / v) after directly extracting the above conditions.

On the other hand, it will be apparent to those skilled in the art that the extract of the present invention can be obtained white acid tea extract, which exhibits substantially the same effect using not only the aforementioned extraction solvent but also other extraction solvents.

In addition, the extract of the present invention includes not only the extract by the above-described extraction solvent, but also the extract that has undergone a conventional purification process. Obtained by various additional purification methods, such as, for example, separation using an ultrafiltration membrane having a constant molecular weight cut-off value, separation by various chromatography (manufactured for separation according to size, charge, hydrophobicity or affinity). The fraction is also included in the white tea extract of the present invention.

White acid tea extract of the present invention may be prepared in a powder state by an additional process such as vacuum distillation and freeze drying or spray drying.

White acid tea extract of the present invention is characterized in that it is used as a skin whitening component. The white tea extract has an effect of inhibiting melanin production from tyrosine by inhibiting the activity of tyrosinase and inhibiting melanin production in melanocytes.

White acid tea extract in the composition of the present invention comprises an effective amount of white acid tea extract that can inhibit tyrosinase activity or inhibit melanin production of melanocytes.

The cosmetic composition of the present invention may include other skin whitening ingredients in addition to the white tea extract as an active ingredient. However, the cosmetic composition of the present invention shows an excellent skin whitening effect even with an active ingredient consisting only of white acid tea extract.

According to a preferred embodiment of the present invention, the content of the white acid tea extract is 0.00001-20% by weight, preferably 0.0001-10% by weight, more preferably 0.001-10.0% by weight based on the total weight of the cosmetic composition.

At this time, when the content of white acid tea extract contained in the cosmetic composition is less than the minimum content, there is a problem that the improvement of the whitening effect through inhibition of tyrosinase activity and inhibition of melanin production of melanocytes is somewhat insufficient, and exceeds the maximum content. In this case, the apparent whitening effect does not increase any more and is likely to cause irritation to the skin and greatly affects the stabilization of the formulation.

Ingredients included in the cosmetic composition of the present invention as an active ingredient includes components conventionally used in cosmetic compositions in addition to the active ingredient, for example, conventional auxiliaries such as antioxidants, stabilizers, solubilizers, vitamins, pigments and flavors, And carriers.

The cosmetic composition of the present invention may be prepared in any formulation commonly prepared in the art, for example, solutions, suspensions, emulsions, pastes, gels, creams, lotions, powders, soaps, surfactant-containing cleansing , Oils, powder foundations, emulsion foundations, wax foundations and sprays, and the like can be formulated, but is not limited thereto. More specifically, it may be prepared in the form of a flexible lotion, nutrition lotion, nutrition cream, massage cream, essence, eye cream, cleansing cream, cleansing foam, cleansing water, pack, spray or powder.

When the formulation of the present invention is a paste, cream or gel, animal oils, vegetable oils, waxes, paraffins, starches, trachants, cellulose derivatives, polyethylene glycols, silicones, bentonites, silicas, talc or zinc oxide may be used as carrier components. Can be.

When the formulation of the present invention is a powder or a spray, lactose, talc, silica, aluminum hydroxide, calcium silicate or polyamide powder may be used, in particular in the case of a spray, additionally chlorofluorohydrocarbon, propane Propellant such as butane or dimethyl ether.

When the formulation of the present invention is a solution or emulsion, a solvent, solubilizer or emulsifier is used as the carrier component, such as water, ethanol, isopropanol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1 Fatty acid esters of, 3-butylglycol oil, glycerol aliphatic ester, polyethylene glycol or sorbitan.

When the formulation of the present invention is a suspension, liquid carrier diluents such as water, ethanol or propylene glycol, suspending agents such as ethoxylated isostearyl alcohol, polyoxyethylene sorbitol esters and polyoxyethylene sorbitan esters, and microcrystalline as carrier components Soluble cellulose, aluminum metahydroxy, bentonite, agar or tracant and the like can be used.

When the formulation of the present invention is a surfactant-containing cleansing, the carrier component is aliphatic alcohol sulfate, aliphatic alcohol ether sulfate, sulfosuccinic acid monoester, isethionate, imidazolinium derivative, methyltaurate, sarcosinate, fatty acid amide. Ether sulfates, alkylamidobetaines, aliphatic alcohols, fatty acid glycerides, fatty acid diethanolamides, vegetable oils, lanolin derivatives or ethoxylated glycerol fatty acid esters and the like can be used.

Hereinafter, the present invention will be described in more detail through experimental examples. These experimental examples are only for illustrating the present invention in more detail, and it is obvious to those skilled in the art that the scope of the present invention is not limited by them according to the gist of the present invention. something to do.

Preparation Example 1 Preparation of White Acid Tea Extract I

After washing with purified water, 200 g of dried white tea leaves were placed in 1.2 L of water and heated at 70-90 ° C. for 5 hours in an extractor equipped with a cooling condenser to extract the active ingredient, followed by filtration with 300 mesh filter cloth, and filtering at 5-10 ° C. After aging for 10 days, it was filtered through Whatman No. 5 filter paper. This filtrate was dried at 65 ° C. with a rotary immersion evaporator to obtain a dry weight of 18.1 g. The dried powder was dissolved in 1% (w / v) in 50% 1,3-butylene glycol solution and used in the present invention.

Preparation Example 2 Preparation of White Acid Tea Extract II

After washing with purified water, 200 g of dried white tea leaves were placed in 1.2 L of water, extracted active ingredients at 15-35 ° C. for 5 days, filtered through 300 mesh filter cloth, filtered through filter paper of Wattman No. 5, and again with a rotary vacuum evaporator. The ship was concentrated. 0.6 L of 100% ethanol was added thereto, left at 5-10 ° C. for 7-10 days, aged, and filtered through Whatman No. 5 filter paper. The filtrate was dried at 65 ° C. with a rotary light evaporator to obtain a dry weight of 18.5 g. The dried powder was dissolved in 1% (w / v) in 50% 1,3-butylene glycol solution and used in the present invention.

Production Example  3 to 21. White car  Preparation of Extract III

After washing with purified water and dried 200 g of Paeksan tea leaves into 1.2L of the extraction solvent of Table 1 and extracting the active ingredient at 4-40 ℃ for 5 days, filtered through 300 mesh filter cloth, and left for 5-10 ℃ at 7-10 days After aging, the filter was filtered using Whatman 5 filter paper. The filtrate was dried at 65 ° C. with a rotary immersion evaporator to obtain a dry weight as shown in Table 1 below. The dried powder of each sample was dissolved in 1% (w / v) in 50% 1,3-butylene glycol solution and used in the present invention.

Manufacturing example number Extraction solvent Dry weight of the final extract (unit: g) 3 water 15.5 4 10% ethanol 18.9 5 20% ethanol 19.8 6 30% ethanol 16.7 7 40% ethanol 18.7 8 50% ethanol 19.7 9 60% ethanol 19.5 10 70% ethanol 19.8 11 80% ethanol 18.3 12 90% ethanol 19.1 13 100% ethanol 18.5 14 Methanol 18.4 15 n-propanol 17.5 16 Isopropanol 15.6 17 2-butanol 15.3 18 Acetone 15.5 19 chloroform 16.4 20 Ethyl acetate 15.5 21 Butyl acetate 16.6

Production Example  22. White car  Preparation of Extract IV

After washing with purified water and putting 200 g of dry white tea leaves into 1.2 L of 1,3-butylene glycol, extracting the active ingredient for 48 hours, filtering it with 300 mesh filter cloth, and aging by leaving it at 5-10 ° C. for 7-10 days. It was filtered by Whatman 5 filter paper. The extract was again dried to obtain a final concentration of 1% (w / v). The dried powder was dissolved in 1% (w / v) in 50% 1,3-butylene glycol solution and used in the present invention.

Production Example  23 to 32. White car  Preparation of Extracts V

After washing with purified water and 200g of dried white acid tea leaves into 1.2L of extraction solvent of Table 2, the extract was equipped with a cooling condenser and heated at 70-90 ° C. for 5 hours to extract the active ingredient and then filtered with 300 mesh filter cloth. After aging for 5 to 10 days at 5-10 ° C., the filter was filtered using Whatman No. 5 filter paper. The extract was dried with a rotary evaporator at 65 ° C. to obtain a dry weight as shown in Table 2 below. The dried powder of each sample was dissolved in 1% (w / v) in 50% 1,3-butylene glycol solution and used in the present invention.

Manufacturing example number Extraction solvent Dry weight of the final extract in g 23 10% ethanol 16.3 24 20% ethanol 18.7 25 30% ethanol 18.5 26 40% ethanol 18.8 27 50% ethanol 16.5 28 60% ethanol 17.2 29 70% ethanol 18.5 30 80% ethanol 17.3 31 90% ethanol 16.3 32 100% ethanol 18.0

Experimental Example  One. White car  Inhibition of Tyrosinase Activity of Extracts.

40 μl of 1.5 mmol / L tyrosine (Sigma, USA) dissolved in sodium phosphate buffer (pH 6.8) was used as a substrate, and 0.05% of the 1% (w / v) white acid tea extract prepared in Preparation Examples 1 to 32 above was used. Diluted with sodium phosphate buffer (pH 6.8) to prepare a sample solution of 1% (v / v) by volume (final white acid tea extract concentration is 0.01% (w / v)). 240 µl of the sample solution was added to 40 µl of tyrosine, and 20 µl of tyrosinase (Sigma, 1500 U / ml) was added to the mixed solution, followed by reaction at 37 ° C. for 15 minutes, followed by absorbance at 490 nm. Was measured and no white tea extract was used as a control. Tyrosinase activity inhibition rate was calculated by the following equation (1), the results are shown in Table 3.

Inhibition Rate of Tyrosinase Activity of White Tea Extract (%) Test substance % Tyrosinase activity inhibition Test substance % Tyrosinase activity inhibition Preparation Example 1 64.6 Preparation Example 17 65.8 Preparation Example 2 65.4 Preparation Example 18 64.3 Preparation Example 3 67.5 Preparation Example 19 65.2 Preparation Example 4 64.4 Preparation Example 20 67.1 Preparation Example 5 65.3 Preparation Example 21 68.9 Preparation Example 6 65.7 Preparation Example 22 70.0 Preparation Example 7 64.3 Preparation Example 23 69.0 Preparation Example 8 65.9 Preparation Example 24 65.7 Preparation Example 9 66.9 Preparation Example 25 66.3 Preparation Example 10 68.7 Preparation Example 26 65.9 Preparation Example 11 65.0 Preparation Example 27 64.3 Preparation Example 12 65.8 Preparation Example 28 62.3 Preparation Example 13 67.5 Preparation Example 29 61.6 Preparation Example 14 68.9 Preparation Example 30 60.5 Preparation Example 15 66.5 Preparation Example 31 60.7 Preparation Example 16 68.3 Preparation Example 32 61.5

As can be seen in Table 3, white acid tea extract showed an excellent tyrosinase activity inhibitory effect. Therefore, the composition containing the white acid tea extract of the present invention was found to exhibit an excellent inhibitory effect on tyrosinase activity.

Experimental Example  2. White car  Experiment to inhibit melanin production of extracts.

B-16 cells (rat melanoma cells, Korea Cell Line Bank) were seeded in 12-well plates to 10 ⁴ cells / well and cultured for one day. 1% (w / v) white acid tea extract prepared in Preparation Examples 1 to 32 was diluted with 0.05 M sodium phosphate buffer (pH 6.8) in the same manner as in Experiment 1 to prepare a sample solution of 1% (v / v). (Final white tea extract concentration is 0.01% (w / v)). 240 μl of the sample solution was added to each well and incubated for 3-4 days. Then, the supernatant of the culture solution of each well was removed, and only melanocytes were centrifuged. Centrifuged cells were lysed with 500 μl of 1N NaOH solution dissolved in dimethylsulfoxide (DMSO) and heated in a 90 ° C. water bath for 10 minutes. After centrifugation again, the absorbance of the supernatant was measured at 570 nm. As a control, one that was not treated with white tea extract was used.

Melanin production inhibition was calculated according to the following equation (2), the results are shown in Table 2.

Inhibition rate of melanin production of white tea extract (%) Test substance Melanin production inhibition rate (%) Test substance Melanin production inhibition rate (%) Preparation Example 1 44.6 Preparation Example 17 43.5 Preparation Example 2 47.4 Preparation Example 18 46.7 Preparation Example 3 46.5 Preparation Example 19 48.5 Preparation Example 4 44.4 Preparation Example 20 46.3 Preparation Example 5 45.3 Preparation Example 21 45.3 Preparation Example 6 45.7 Preparation Example 22 47.8 Preparation Example 7 46.5 Preparation Example 23 45.6 Preparation Example 8 44.6 Preparation Example 24 44.5 Preparation Example 9 47.5 Preparation Example 25 44.3 Preparation Example 10 48.5 Preparation Example 26 44.8 Preparation Example 11 45.4 Preparation Example 27 47.8 Preparation Example 12 46.7 Preparation Example 28 48.7 Preparation Example 13 46.3 Preparation Example 29 45.6 Preparation Example 14 46.9 Preparation Example 30 45.3 Preparation Example 15 44.2 Preparation Example 31 45.5 Preparation Example 16 48.8 Preparation Example 32 41.5

As can be seen in Table 4, it was confirmed that the white tea extract has an excellent effect on the melanin production inhibition of melanoma cells. In addition, no cytotoxicity was observed in each experiment.

Hereinafter, the formulation examples of the cosmetic composition containing a white acid tea extract, for example, but specifically present a composition of the present invention is not limited to these formulations.

Formulation Example 1 Flexible Lotion

Formulation example of the flexible longevity containing the white acid tea extract obtained by the method of Preparation Example 10 was prepared in the composition of Table 5 according to a conventional method (Example 1), softening that the white acid tea extract is not added as a comparison group Longevity (Comparative Example 1) was also prepared.

ingredient Content (% by weight) Example 1 Comparative Example 1 White Tea Extract Acetate Tocopherol Ole Alcohol Ethanol Benzophenone-9 Carboxylvinyl Polymer Cellulose Gum Flavor Preservative Purified Water 2.0 5.2 1.5 3.2 2.0 1.0 3.5 Minor balance -5.2 1.5 3.2 2.0 1.0 3.5 Minor balance system 100 100

Formulation example  2. milk  Lotion

Formulation example of the milk lotion containing the white acid tea extract obtained by the method of Preparation Example 10 was prepared in the composition of Table 6 according to a conventional method (Example 2), the milk does not add white acid tea extract as a comparative group Lotions (Comparative Example 2) were also prepared.

ingredient Content (% by weight) Example 2 Comparative Example 2 White Acid Tea Extract Glycerin Propylene Glycol Tocopheryl Acetate Liquid Paraffin Triethanolamine Squalane Macadamia Nut Oil Polysorbate 60 2.0 5.1 4.2 3.0 4.6 1.0 3.1 2.5 1.6 1.6 0.6 1.5 Minor balance -5.1 4.2 3.0 4.6 1.0 3.1 2.5 1.6 1.6 0.6 1.5 Trace Amount system 100 100

Formulation example  3: nutrition cream

Formulation example of nutrition cream containing white acid tea extract obtained by the method of Preparation Example 10 was prepared in the composition of Table 7 according to a conventional method (Example 3), nutrition that does not add white acid tea extract as a comparative group A cream (Comparative Example 3) was also prepared.

ingredient Content (% by weight) Example 3 Comparative Example 3 White Tea Extract Glycerin Vaseline Triethanolamine Liquid Paraffin Squalane Beeswax Tocopheryl Acetate Polysorbate 60 Carboxylvinyl Polymer Sorbitasesquioleate Flavor Preservative 4.0 4.0 3.5 2.1 5.3 3.0 2.6 5.4 3.2 1.0 3.1 Minor balance -4.0 3.5 2.1 5.3 3.0 2.6 5.4 3.2 1.0 3.1 Trace Amount system 100 100

Experimental Example  3. Cosmetics  Whitening effect of the composition.

A whitening effect test of a cosmetic composition containing white acid tea extract of the present invention was performed on 30 Korean women, especially 19-40 years old, with dark skin. 5 parts of the arms are measured by 1 cm in width and length, and the cosmetics of Examples 2 and 3 and Comparative Examples 2 and 3 prepared in Formulation Examples 2 and 3 were applied to each of the two, and the other one was compared. It was used as a control for. Each cosmetic was applied steadily for 8 weeks at intervals of 2 weeks, after 8 weeks to measure the skin color (L value) using Minolta CR 300 and calculated the degree of change of skin color (ΔL) according to Equation 3 below, The results are shown in Table 8 below.

Skin color change (ΔL) = L value before cosmetic application-L value after cosmetic application

Skin color gradient (ΔL) division Example 2 Example 3 Comparative Example 2 Comparative Example 3 Control △ L value 0.84 1.01 0.25 0.32 0.00

As shown in Table 8, ΔL values after 8 weeks, cosmetic Examples 2 and 3 of the present invention containing white acid tea extract is significantly superior to Comparative Examples 2, 3 and the control group does not contain white acid tea extract High. Therefore, it can be seen that the cosmetic composition of the present invention has a very good whitening effect.

Experimental Example 4: Skin irritation test of the cosmetic composition

Skin irritation of the products prepared according to the preparation and comparative examples was conducted in 50 healthy adults male and female. After a certain amount (approximately 0.1 g) of each sample (Examples 1 to 3 and Comparative Examples 1 to 3) was patched for 24 hours at 5 X 20 cm 2 in the lower arm of each subject, after 1 hour and 24 hours had elapsed. The skin condition change was visually checked, and the degree of skin reaction was determined according to the skin reaction evaluation criteria of Table 9. In addition, the skin irritation rate was calculated according to Equation 4 based on the result of the determination, and the results are shown in Table 10.

Skin Response Evaluation Criteria division Skin response No erythema or unusual symptoms - Slightly redder than the surroundings -+ Significantly redder than the surroundings + Severe redness and swelling than around ++

Skin reaction degree (persons) and skin reaction rate (%)  Formulation  Judgment result (person)  Stimulation rate (%) ++ + +- - Example 1 - - 2 48 1.33 Example 2 - - 3 47 2.00 Example 3 - - 3 47 2.00 Comparative Example 1 - - 2 48 1.33 Comparative Example 2 - - 3 47 2.00 Comparative Example 3 - - 3 47 2.00

As can be seen in Table 10, the cosmetic composition of Examples 1 to 3 of the present invention containing white acid tea extract has a similar skin irritation rate compared to the cosmetic composition of Comparative Examples 1 to 3 not containing white acid tea extract. It can be seen that the white tea extract of the present invention shows little irritation to the skin. Therefore, the cosmetic composition of the present invention was found to have less skin irritation and excellent skin safety.

As described in detail above, the present invention provides a cosmetic composition for skin whitening comprising white acid tea extract as an active ingredient. White acid tea extract of the present invention has an improved inhibitory effect on tyrosinase activity and excellent melanin production of melanocytes, compared to the conventional whitening component, the cosmetic composition comprising the white acid tea extract of the present invention shows an excellent skin whitening effect . In addition, the white acid tea extract of the present invention can be effectively used as an active ingredient of the cosmetic composition because it hardly irritates the skin.

Claims (4)

Cosmetic composition for skin whitening containing white acid ( Ledum palustre ) extract as an active ingredient. According to claim 1, wherein the white tea extract is a solvent selected from the group consisting of water, anhydrous or hydrous lower alcohol having 1 to 4 carbon atoms, acetone, ethyl acetate, chloroform, butyl acetate and 1,3-butylene glycol Cosmetic composition for skin whitening, characterized in that the extract extracted by. The cosmetic composition for skin whitening according to claim 1, wherein the white acid extract is contained in an amount of 0.00001-30.0% (w / w) based on the total weight of the composition of the cosmetic composition. The composition of claim 1 wherein the cosmetic composition consists of a solution, suspension, emulsion, paste, gel, cream, lotion, powder, soap, surfactant-containing cleansing, oil, powder foundation, emulsion foundation, wax foundation and spray Cosmetic composition for skin whitening, characterized in that the formulation is selected from the group.