KR20050080627A - A manufacturing method of chitosan microcapsules and cosmetic composition containing chitosan microcapsules - Google Patents

Abstract

The present invention relates to a method for producing a chitosan microcapsules having a size of 0.5 ~ 20.0㎛ containing fat-soluble vitamins, vitamin derivatives or fat-soluble active ingredients, and more particularly, to a cosmetic composition containing the same. And a method for preparing chitosan microcapsules using chitosan in water-in-oil (W ₁ / O / W ₂ ) type emulsion preparation and an anionic surfactant, coacervation enhancing component and insoluble complex formation with chitosan. The prepared chitosan microcapsules can be prepared in an oil-in-water (O / W) cosmetic composition with an appropriate anionic, nonionic or cationic polymer added.

Description

A manufacturing method of chitosan microcapsules and cosmetic composition containing chitosan microcapsules}

The present invention relates to a method for producing a chitosan microcapsules having a size of 0.5 ~ 20.0㎛ containing fat-soluble vitamins, vitamin derivatives or fat-soluble active ingredients, and more particularly, to a cosmetic composition containing the same. And a method for preparing chitosan microcapsules using chitosan in water-in-oil (W ₁ / O / W ₂ ) type emulsion preparation and an anionic surfactant, coacervation enhancing component and insoluble complex formation with chitosan. The prepared chitosan microcapsules can be prepared in an oil-in-water (O / W) cosmetic composition with an appropriate anionic, nonionic or cationic polymer added.

In general, vitamin C, vitamin derivatives, and retinoid-based retinol, retinic acid, and retinaldehyde are oxidized by heat, light, pH, and oxygen in the air or other solvents, and are easily destabilized. Will cause irritation. In particular, retinol is known as a difficult substance in the application of products because it exhibits activities such as antioxidant and wrinkle improvement and is easily decomposed by a widely used substance or outside air, causing an unpleasant odor and showing toxicity. Therefore, various methods for stabilizing these components have been developed, and a number of methods for preparing microcapsules for preventing oxidation through encapsulation have been developed.

The encapsulation method using coacervation as a conventional method has been known so far, and in general, in the method using an ionic salt which induces coacervation by adding a temperature change, a pH change, an opposite ion salt or a solvent and exhibits an opposite ion Gelatin and acacia gum are mainly used. In addition, methods of using anionic and cationic surfactants, as well as coacervation between polymers, have also been proposed. However, these methods induce coacervation primarily by preparing an emulsion of the type underwater and adding a polymer or salt that represents the opposite ions or by dropping it in an aqueous solution of polymer or surfactant that exhibits the opposite charge. The problem with this method is that it is difficult to refine the resulting capsules and the resulting agglomerates caused by the polymer insolubilizing.

Currently encapsulation methods using chitosan include spray drying, matrix capsules with carboxymethyl cellulose or alginate salts, encapsulation by pH control, spray drying, and crosslinking agents (International Journal of Pharmaceutics 187 (1999) 53-65, J. MICROENCAPSULATION, 1999, VOL 16, NO 6, 687-696, Journal of Controlled Release 52 (1998) 109-118).

Korean Patent No. 306221 relates to a method for producing a sustained release microcapsules using chitosan microcapsules and emulsification using double crosslinking of chitosan, sulfuric acid, and glutaraldehyde in order to maintain an appropriate release rate for a long time. Chitosan microcapsules of less than a few microns are described using the interfacial reaction method. In addition, Korean Patent No. 271315 relates to a method of encapsulating retinol and derivatives thereof using marine collagen and chitosan as a matrix, and preparing an oil-in-water cosmetic composition. Republic of Korea Patent Publication No. 1990-58599 relates to a cosmetic composition having a double capsule structure to liposome the active substance and matrix encapsulation using chitosan.

In addition, the patents related to cosmetics to which chitosan is added include Unexamined Patent Publication Nos. 2000-0040847, 1998-028150, 2002-0095154, and 2003-0007446.

The present invention provides a method for easily preparing chitosan microcapsules with chitosan, anionic surfactants, and coacervation-enhancing components using a water-in-oil (W ₁ / O / W ₂ ) type multi-emulsion preparation method as an encapsulation method. It aims to do it. Rather than simply mixing with water-in-oil (W ₁ / O / W ₂ ) type multiple emulsion production method used in the conventional cosmetic preparation, the present invention reacts at the interface using chitosan and anionic surfactants to prevent insoluble membranes. It is made by the method of forming.

In addition, another object of the present invention is to provide a cosmetic composition that can be delivered safely to the skin by stabilizing chitosan microcapsules by containing a highly irritating and unstable active ingredient.

In order to achieve the above object, the present inventors formed chitosan microcapsules by forming an insoluble ionic complex with chitosan, anionic surfactant, and coacervation enhancing component using water-in-oil (W ₁ / O / W ₂ ) type emulsion. Prepared. That is, an anionic surfactant and coacervation reinforcing component are added to the inner aqueous phase of a water-in-oil (W ₁ / O / W ₂ ) type emulsion, and chitosan, a cationic polymer, is added to the outer water to prevent the formation of unnecessary polymers. To prepare a capsule of 0.5 ~ 20.0㎛ size by a simpler method.

The present invention is 100% by weight of the total composition for the preparation of chitosan capsules,

(a) A primary water-in-oil (W ₁ / O) type emulsion is dispersed by dispersing an aqueous solution containing 0.01-20.0 wt% of anionic surfactant and 0.001-5.0 wt% of coacervation enhancing component. Manufacturing step;

(b) the first water-in-oil (W ₁ / O) type chitosan 0.01 ~ 20.0% by weight of surface active agent 0.01 ~ 20.0 the external water phase% is added by weight of the emulsion (W ₂₎ the male of the oil-in-water dispersion in (W ₁ / O / W ₂ ) preparing multiple emulsions;

(c) an anionic surfactant and coacervation enhancing component at the oil / water interface of the multi-emulsion in water-in-oil (W ₁ / O / W ₂ ) type to form an insoluble complex with chitosan; It relates to a method for producing a capsule.

In addition, the present invention, the anionic surfactant is at least one member of the group consisting of sodium lauryl sulfate, potassium lauryl sulfate, sodium myristyl sulfate, sodium cetyl sulfate, sodium lauryl phosphate, polyoxyethylene alkyl ether sulfate and lecithin It is characterized by using.

In addition, the present invention is characterized in that the coacervation enhancing component uses one or more of the group consisting of sodium phosphate, sodium citrate, sodium sulfate, sodium carbonate and sodium acetate.

In addition, the present invention is characterized in that the oil-soluble active ingredient contains at least one selected from vitamins, derivatives thereof, 7-dihydrocholesterol, oil-soluble samcho extract, gamma-orizanol or ceramide.

In addition, the present invention, the surfactant present in the outer water phase (W ₂ ) is a water-soluble dimethicone copolyol, poloxamer, PEG-60 hydrogenated castor oil, polysorbate 20, polysorbate 40, polysorbate 61 Or it is characterized by containing one selected from polysorbate 80.

In addition, the present invention is prepared by the above method, chitosan, characterized in that it contains at least one selected from vitamins, vitamin derivatives, 7-dihydrol cholesterol, oil-soluble vinegar extract, gamma-orizanol or ceramide as an active ingredient Relates to a microcapsule.

Furthermore, the present invention relates to a cosmetic composition containing the chitosan microcapsules.

Thus, the configuration of the present invention in detail as follows.

The present invention applied chitosan that can be dissolved in a wide range of pH conditions, examples of suitable chitosan for this is' JAKWANG CHITOSAN, which is commercially available from Gwanggwang Co., Ltd., having a deacetylation degree of 80% or more and an average molecular weight of about 300,000 to 400,000 Da. Cosmetic Grade 'and the range of average molecular weight is not limited. The chitosan has the characteristic of preparing a solution having a pH of various regions. The type of chitosan used is not limited, and any form of chitosan soluble in water may be used. In particular, when encapsulating the active ingredient sensitive to pH, it is preferable to use chitosan that is easy to adjust the pH. In addition to chitosan, other kinds of linear polymers showing cations can also be used.

As anionic surfactants, those having excellent solubility in water are suitable. In order to form an insoluble complex effectively at the interface between oil and water, those having strong anion properties are used. Therefore, any water-soluble anionic surfactant can be used. Preferably C ₆ ~ C ₁₈ alkyl sulphate, phosphate metal salt is suitable and in the embodiment of the present invention was prepared microcapsules using sodium lauryl sulphate. More preferably, potassium lauryl sulfate, sodium myristyl sulfate, sodium cetyl sulfate, sodium lauryl phosphate, sulfate, polyoxyethylene alkyl ether sulfate, phosphate, metal salt of alkyl ether carboxylic acid or lecithin and the like can be used.

Coacervation enhancer was added to enhance the formation of the composite (membrane) at the interface, and sodium phosphate, sodium citrate, sodium sulfate, sodium carbonate, or sodium acetate may be used. It is important to keep.

Of the active ingredients encapsulated, oil-soluble active ingredients are suitable and examples thereof include oil-soluble vitamins and derivatives thereof, retinol, retinol palmitate, vitamin C tetrapalmitate, tocopherol or tocopheryl acetate. In addition, sunscreen may also be added and suitable examples thereof include 2-ethylhexyl 4-methoxy cinnamate, propyl 4-ethoxycinnamate, isoamyl 4-methoxy cinnamate, octocrylene, esters of salicylic acid, benzo Derivatives of phenone, derivatives of triazine and the like can be added. In addition, in addition to the active ingredient, fats, waxes, oils, flavors, ceramides or oil-soluble plant extracts may be contained as active ingredients, and 0.01 to 20% by weight is added to the total weight.

In surfactant added to an external water phase, it is preferable that it is water-soluble and is compatible with chitosan. Anionic surfactants are inappropriate because they form complexes with chitosan. Therefore, water-soluble nonionic surfactants are suitable. Examples include water-soluble dimethicone copolyols, poloxamers, PEG-60 hydrogenated castor oils, polysorbate 20, polysorbate 40, polysorbate 61, or polysorbate 80, which are compatible with chitosan. have.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, these examples are merely illustrative of the present invention and the scope of the present invention is not limited to these examples.

<Examples 1-5: Preparation of Chitosan Microcapsules>

In this embodiment, chitosan microcapsules were prepared according to the content of sodium lauryl sulfate, an anionic surfactant, and the degree of insoluble film formation of the microcapsules was confirmed by measuring the zeta potential. First, in the composition ratio of Table 1, the aqueous phase (A) was physically dispersed in the oil phase (B) to prepare a primary water-in-oil (W ₁ / O) type emulsion. The prepared primary water-in-oil (W ₁ / O) emulsion was added to the external aqueous phase (C) containing chitosan to emulsify to prepare a water-in-oil (W ₁ / O / W ₂ ) multiple emulsion. As in progress, an insoluble complex of chitosan and sodium lauryl sulfate was formed at the interface between the external water phase (W ₂ ) and the water-in-oil (W ₁ / O) to complete the preparation of the retinol-encapsulated capsule.

 ingredient Content (% by weight) Example 1 Example 2 Example 3 Example 4 Example 5 (A) Purified water 1.0 1.0 1.0 1.0 1.0 Sodium Lauryl Sulfate 0.15 0.09 0.03 0.015 0.00 Sodium citrate 0.02 0.02 0.02 0.02 0.02 (B) Squalane 15.0 15.0 15.0 15.0 15.0 Retinol 10S 10.0 10.0 10.0 10.0 10.0 Butylated hydroxy toluene 0.03 0.03 0.03 0.03 0.03 (C) Chitosan 0.7 0.7 0.7 0.7 0.7 Dimethicone Copolyol 0.7 0.7 0.7 0.7 0.7 Purified water Remaining amount

The zeta potential measurement of the chitosan microcapsules of Examples 1 to 5 used a buffer solution of pH 4.80 in order to exclude the influence of pH, and the content of chitosan was fixed at 0.70 wt% according to the composition of Table 1. The zeta potential (+) was measured by changing the content of sodium lauryl sulfate, anionic surfactant, from 0.00% to 0.15% by weight. As a result of the measurement, it was confirmed that the zeta potential showed a larger value as the content of sodium lauryl sulfate added to the internal aqueous phase increased (Table 2). This confirmed that an insoluble film of the microcapsules was formed.

Sodium Lauryl Sulfate Content (% by weight) Zeta-Potential (mV) Example 5 (0.00 wt.%) +1.3 Example 4 (0.015 wt.%) +14.5 Example 3 (0.03% by weight) +25.3 Example 2 (0.09 weight%) +25.7 Example 1 (0.15 wt.%) +28.3

<Example 6 and Comparative Example 1: Preparation of skin irritation test product>

This example is for reducing the skin irritation of the chitosan capsule was prepared by the retinol content of about 8500 IU / g. Example 6 was added to the encapsulated retinol was added to Example 2 prepared, Comparative Example 1 was mixed and prepared by adding the liquid retinol directly.

 ingredient Content (% by weight) Example 6 Comparative Example 1 Purified water Remaining amount Remaining amount Polyacrylamide / C12-14 Iso Paraffin / Laureth-7 1.0 1.0 Retinol 10S - 2.5 Example 2 25.0 -

<Example 7 and Comparative Example 2: Preparation of oil-in-water (O / W) type cream with chitosan microcapsules>

This example is to prepare a cream to which chitosan capsules are added, was prepared by emulsifying (A) and (B) at 80 ℃ according to the composition of Table 4 and adding (C) phase at 40 ℃. Example 7 used retinol encapsulated by the addition of Example 2 and Comparative Example 2 directly used Retinol 10S (BASF) having a titer of 340,000 IU / g.

ingredient Content (% by weight) Example 7 Comparative Example 2 (A) Purified water Remaining amount Remaining amount DL-panthenol 0.5 0.5 Methyl Paraben 0.2 0.2 1,3-butylene glycol 5.0 5.0 Hydroxy ethyl cellulose 1.0 1.0 Triethanolamine Quantity Quantity (B) Steares-2 1.3 1.3 Steares-21 2.3 2.3 Cetyl alcohol 1.0 1.0 Butylene Glycol Dicaprylate / Dicaprate 5.0 5.0 Dimethicone 5.0 5.0 Dimethicone / Polysilicone-11 2.0 2.0 Paraffin wax 0.5 0.5 Behenyl Alcohol 1.0 1.0 (C) Example 2 10.0 - Retinol 10S - 1.0

Experimental Example 1: Skin irritation reduction experiment

The skin irritation reduction test of the retinol-encapsulated chitosan capsules of the present invention was performed. The content of retinol was tested by determining the concentration sufficient to cause irritation. 20 women in their twenties and thirties, using a steam generator (Steam) enough to sweat (sweating), Example 6 is applied to the left face, Comparative Example 1 is evenly applied to the right face. The stimulus grades were evaluated as being classified as strong stimulus, medium stimulus within 2.5 minutes, mild stimulus within 5 minutes, and non-irritating within 8 minutes according to the time of stimulation after application. However, panels with skin lesions such as psoriasis and eczema were excluded from the experiment. After applying Example 6 and Comparative Example 1 to the face, the skin reaction (itch, itching, redness, etc.) observed for 8 minutes was observed and the degree of stimulation was obtained by dividing the degree of stimulation by the number of subjects (n) to obtain the rate of stimulation (%). Was evaluated. The degree of skin irritation according to the stimulation positive rate was determined according to Table 5 below and the results are shown in Table 6.

 Rating Irritation rate (%) Judgment One 0.00-0.75 Non-irritating 2 0.76-1.50 Weak stimulation 3 1.51-2.50 Light stimulation 4 2.51-4.00 Heavy stimulation 5 4.01 or higher Strong stimulation

 Rating Example 6 Comparative Example 1 Irritation rate (%) 1.68 4.76 Judgment Light stimulation Strong stimulation Grade 3 3 5

Example 6 by the skin irritation reduction test was determined to be a mild stimulation (%) of stimulation positive (%), but this shows a very low skin irritation compared to Comparative Example 1. It can be seen that the chitosan capsules applied to the present invention effectively control (sustained release) useful oils having strong skin irritation properties.

Experimental Example 2 Measurement of Change in Retinol Content

      Changes in the content of retinol in oil-in-water (O / W) type creams containing chitosan microcapsules containing retinol were analyzed by HPLC (5 μm, 4.6 250 mm C18 reversed phase column, flow rate 0.8 mL / min, mobile phase methanol, 325 nm). The storage conditions were 45 ℃ and 60% humidity. The results are listed in Table 7 below. From the results in Table 7, it was confirmed that the retinol-encapsulated chitosan microcapsules prepared in the present invention effectively and stably maintain retinol that is sensitive to temperature rise in oil-in-water (O / W) type cream products.

Remaining Retinol Content (% by Weight, 45 ° C) 10 days past 20 days past 30 days past 40 days have passed Example 7 96 93 90 88 Comparative Example 2 88 75 60 45

Experimental Example 3: Improved Feeling Effect

Twenty women in their 20s and 30s were allowed to use Example 6 without chitosan microcapsule and Comparative Example 1 evenly after washing the face, and then evaluated the feeling and satisfaction by the 5-point evaluation method. The results are shown in Table 6, and the higher the number, the more positive the effect. As a result, it was confirmed that the feeling of Example 6 is much better due to the unique feeling of chitosan, which is the material of the chitosan microcapsules.

Feeling Example 6 Comparative Example 1 Sticky 4.3 3.5 Oiliness 3.8 3.1 Bundle 3.6 3.5 Skin condition 4.1 4.0 satisfaction 4.0 3.5

As described above, the present invention can provide a method for preparing chitosan microcapsules that can stabilize oil-soluble active ingredients more easily using a water-in-oil-in-water multiphase emulsion production method.

In addition, the chitosan microcapsules prepared by the present invention can be added to provide a cosmetic composition of good quality that can safely deliver an irritating, unstable active ingredient to the skin. In particular, chitosan microcapsules have the advantage of being easily applied to the most common oil-in-water (O / W) cosmetics, and stabilize the unstable oil-soluble active ingredients such as retinol, can be released to slow down the stimulation have.

In addition, chitosan, which is a polymer derived from nature, is known to have excellent biocompatibility, nontoxicity, moisturizing property, antimicrobial activity, and biodegradability, and is environmentally friendly and excellent due to its safety and biodegradability using chitosan, which is a biocompatible polymer. It is possible to provide a cosmetic composition having a skin moisturizing effect and excellent feeling without stickiness.

Claims (7)

(a) Primary water-in-oil by dispersing an aqueous solution containing 0.01-20.0 wt% of anionic surfactant and 0.001-5.0 wt% of coacervation-enhancing component with respect to 100 wt% of the total composition. Preparing a ₁ / O) type emulsion; (b) the first water-in-oil (W ₁ / O) type chitosan 0.01 ~ 20.0% by weight of surface active agent 0.01 ~ 20.0 the external water phase% is added by weight of the emulsion (W ₂₎ the male of the oil-in-water dispersion in (W ₁ / O / W ₂ ) preparing multiple emulsions; (c) an anionic surfactant and coacervation enhancing component at the oil / water interface of the multi-emulsion in water-in-oil (W ₁ / O / W ₂ ) type to form an insoluble complex with chitosan; Method of Making Capsules. The method of claim 1, wherein the anionic surfactant comprises at least one selected from the group consisting of sodium lauryl sulfate, potassium lauryl sulfate, sodium myristyl sulfate, sodium cetyl sulfate, sodium lauryl phosphate, polyoxyethylene alkyl ether sulfate and lecithin. Method for producing a chitosan microcapsule, characterized in that it is used. The method of claim 1, wherein the coacervation enhancing component uses at least one of the group consisting of sodium phosphate, sodium citrate, sodium sulfate, sodium carbonate and sodium acetate. The method of claim 1, wherein the oil-soluble active ingredient contains one or more selected from vitamins, derivatives thereof, 7-dihydrocholesterol, oil-soluble tricholic extract, gamma-orizanol or ceramide. . The surfactant of claim 1, wherein the surfactant present in the outer aqueous phase (W ₂ ) is a water soluble dimethicone copolyol, poloxamer, PEG-60 hydrogenated castor oil, polysorbate 20, polysorbate 40, polysorbate. A method for producing chitosan microcapsule, characterized in that it contains one selected from 61 or polysorbate 80. It is prepared by the method according to any one of claims 1 to 5, containing one or more selected from vitamins, vitamin derivatives, 7-dihydrolol cholesterol, oil-soluble vinegar extract, gamma-orizanol or ceramide as an active ingredient Characterized chitosan microcapsules. Cosmetic composition containing chitosan microcapsules of Claim 6.