KR100825834B1 - Method for producing oil-soluble active substance stabilized thermotropic liquid crystal microcapsules using liquid crystal array stabilization system (LAS) and cosmetic composition containing the same - Google Patents

Abstract

The present invention relates to a liquid crystal crosslinked polymer microcapsules stabilized with an oil-soluble active substance, a method for preparing the same, and a cosmetic composition containing the liquid crystal crosslinked polymer microcapsules. Such liquid crystal crosslinked polymer microcapsules may include polymerizing a polymer having a functional group capable of crosslinking; Preparing a thermotropic liquid crystal polymer capsule; Capturing the oil-soluble active substance in the capsule; The oil-soluble active material may be prepared by a method comprising the step of crosslinking the collected liquid crystal polymer capsules. In the thus prepared liquid crystal crosslinked polymer capsule, the oil-soluble active material is mixed with the liquid crystal present in the polymer particles, thereby blocking the active material from the external stimulus by the liquid crystal inside the particle and the polymer crosslinked network outside the particle. Dual stabilization system shows excellent stabilization effect.

Liquid crystal * crosslinked polymer * capsule * useful component stabilization

Description

Method for preparing an oil-soluble active substance stabilized thermotropic liquid crystal microcapsules using a liquid crystal array stabilization system (LASS), and a cosmetic composition containing the same (Thermotropic liquid crystal microcapsules for the stabilization of water-insoluble active ingredients by liquid crystal association stabilization system (LASS) and the process for preparing the same, and the cosmetic composition containing the microcapsules}

Figure 1 is a confocal laser scanning micrograph of the distribution of the retinol in the liquid crystal crosslinked polymer capsule prepared in the present invention.

The present invention relates to a liquid crystal cross-linked polymer microcapsules capable of stabilizing the oil-soluble active substance, a method for preparing the same, and a cosmetic composition containing the liquid crystal cross-linked polymer microcapsules. The present invention relates to a microcapsule that can be stabilized by a polymer crosslinked network in a double manner so that the active substance can be exhibited for a long time. This technique is called a liquid crystal association stabilization system (LASS).                         

It is widely used in cosmetics due to its excellent effect of improving skin wrinkles and strengthening moisturizing power, but it is widely used in cosmetics for stabilizing useful active substances that have problems such as discoloration and odor due to contact with external stimuli such as air or moisture, and reduced potency. Is actively underway. Among these active substances, retinol has been of great interest due to its excellent anti-wrinkle effect, but its use is extremely limited as one of the most unstable components easily destroyed by light, heat, air, and moisture. To overcome these limitations and look at the methods for stabilizing retinol in the formulation in detail, European Patent No. 440398 and WO 93/00085 stabilized the retinol in the oil-in-water emulsion form by the addition of antioxidants and chelating agents. In addition, US Patent 5851538 proposes a porous microparticles to improve the stability of retinol and reduce skin irritation. In addition, US Patent 6183774 attempts to stabilize retinol using cationic liposomes, US Patent 5985296 proposes a method for stabilizing retinol using a cyclodextrin.

However, although these conventional methods have improved the stability of retinol, they are not yet satisfactory and the invention of a system that can be widely used to stabilize other useful components other than retinol is urgent.

In addition, the development of stabilization systems for active ingredients other than retinol is also urgently needed.

Therefore, the present inventors studied a method for stabilizing the oil-soluble active material in the polymer particles, and as a result, found that the suspension was polymerized with a liquid crystal material and a monomer to prepare a capsule, and the active material was introduced into the capsule to be effective in stability. . In order to further improve the stability of the active material, by discovering that the liquid crystal in the crosslinked polymer can be aligned with the active material to completely block the active material from external stimulation by crosslinking the polymer surrounding the liquid crystal, the original liquid crystal crosslinked polymer micro The invention of the capsule was completed.

Accordingly, it is an object of the present invention to provide a liquid crystal crosslinked polymer capsule which can completely stabilize the oil-soluble active material.

Another object of the present invention is to provide a method for producing the capsule. In addition, it provides a method of stabilizing the active material using the liquid crystal capsule.

Still another object of the present invention is to provide a cosmetic composition containing the capsule described above, which retains the efficacy of the active substance for a long time.

The present invention relates to a thermotropic liquid crystal crosslinked polymer capsule and a method for preparing the same, wherein the oil-soluble active material is double stabilized by a liquid crystal material in a particle and a polymer crosslinked network surrounding the liquid crystal, and a polymer having a functional group capable of crosslinking. Polymerizing; Preparing a thermotropic liquid crystal polymer capsule; Capturing the oil-soluble active substance in the capsule; And crosslinking the liquid crystal polymer capsule in which the oil-soluble active substance is collected.

In general, a method of using polymer particles as a method for stabilizing an unstable oil-soluble active material has been widely studied. However, simply encapsulating the oil-soluble active substance in the polymer particles does not completely stabilize the active substance, especially when the particles are used in a formulation such as cosmetics, the polymer swells with water, surfactants, oils, etc. in the formulation. Due to this, the unstable active material may have a problem such as slowly flowing out to the outside for a long time. Therefore, in the present invention, by trapping the oil-soluble active material in the liquid crystal material encapsulated in the polymer particles, inducing a mixture between the liquid crystal and the useful component, thereby immobilizing the useful component in the molecular arrangement of the liquid crystal to stabilize in the liquid crystal, this liquid crystal The double stabilization system is used to stabilize once again in the particles by crosslinking the outer polymer surrounding the shell.

Hereinafter, the manufacturing method of the present invention will be described in detail for each step.

(1) preparing a polymer having a functional group that can be crosslinked:

In this step, a polymer having a crosslinking ability is prepared by copolymerizing a monomer capable of radical polymerization and a monomer having a crosslinking functional group. That is, a common monomer capable of radical polymerization and a monomer having a crosslinking functional group applicable to a postcrosslinking system are copolymerized. In the present invention, the preparation of the polymer having crosslinking capability is preferably using a dispersion polymerization method. The prepared polymer has a characteristic of being capable of crosslinking through radical polymerization during capsule manufacture and synthetic process after capsule manufacture.

The monomer capable of radical polymerization used in the present invention is not particularly limited in kind, and those commonly known to be capable of radical polymerization can be used. Specifically, styrene, p- or m-methylstyrene, p- or m-ethylstyrene, p- or m-chlorostyrene, p- or m-chloromethylstyrene, styrenesulphonic acid, p- or m- or t-butoxystyrene, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) Acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, polyethylene Glycol (meth) acrylate, methoxy polyethylene glycol (meth) acrylate, glycidyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, vinyl acetate, vinyl pro Cypionate, vinyl butyrate, vinyl ether, Allyl butyl ether, allyl glycidyl ether, (meth) acrylic acid, unsaturated carboxylic acids like maleic acid, alkyl (meth) acrylamide, (meth) acrylonitrile, etc. can be used in mixture of 1 or more types.

As a monomer which has a crosslinking functional group to copolymerize with the said monomer which can be radically polymerized, it is preferable to have a silane group and to be capable of radical polymerization. Specifically, trichlorovinylsilane, trimethoxyvinylsilane, triethoxyvinylsilane, vinyltriisooxysilane, vinyltri-t-butoxysilane, vinyltriphenoxysilane, vinyltriacetoxysilane, vinyl tri ( Isobutoxy) silane, vinyltri (2-methoxyethoxy) silane, 8-oct-1-enyltrichlorosilane, 8-oct-1-enyltriethoxysilane, 8-oct-1-enyltriethoxy Silane, 6-hex-1-enyl trichlorosilane, 6-hex-enyl triethoxysilane, etc. can be used in mixture of 1 or more types.

(2) preparing a thermotropic liquid crystal polymer capsule:

In the present invention, the thermotropic liquid crystal polymer capsule may be prepared by a general suspension polymerization method.

The polymer having the thermotropic liquid crystal, the hydrophobic monomer and the crosslinkable functional group prepared in step (1) is uniformly dissolved in an organic solvent, and the solution is emulsified in an aqueous solution in which a dispersion stabilizer of appropriate concentration is dissolved. In this case, the average particle size is determined by the concentration of the dispersion stabilizer and the shear stress applied. Since the polymerization should proceed only in the emulsion droplets prepared, oil soluble initiators are used and a small amount of polymerization inhibitor suitable for the aqueous phase is added.

The liquid crystal used in the present invention is a thermotropic liquid crystal, preferably a cholesterol-based liquid crystal. Cholesterol-based liquid crystals are cholesterol liquid crystals or cholesteryl derivatives, and specific examples thereof include cholesteryl octanoate, cholesteryl nonanoate, cholesteryl oleyl carbonate, and cholesteryl isostearyl carbonate.

This cholesterol liquid crystal can display various colors depending on the temperature and the angle of light, and is useful as a cosmetic raw material because it is harmless to the human body. The amount of liquid crystal used is added in an amount of 0.1 to 50% by weight based on the total capsule particles. This is because when the liquid crystal is added at less than 0.1% by weight, the behavior of the liquid crystal cannot be observed, and when it exceeds 50% by weight, no capsule is formed.                     

The monomers used in this step are the same as the monomers used when preparing the polymer having the crosslinkable functional group, and The use ratio of the polymer having a functional group capable of crosslinking with the monomer is adjusted so that the functional group (silane group) capable of crosslinking is in an amount of 0.1 to 50% by weight based on the total capsule particles. This is because when the crosslinkable functional group (silane group) is added in less than 0.1% by weight, the crosslinking effect cannot be observed, and when it exceeds 50% by weight, the hydrophilic functional group on the surface of the particles prevents the collection of useful components.

Solvents are those that can dissolve the liquid crystals and monomers described above, and those having a low boiling point and little mixing with water are used. Specifically, halogenated alkanes such as chloromethane, dichloromethane, chloroform, tetrachloromethane, dichloroethane, ethyl acetate, diethyl ether, cyclohexane, benzene, toluene and the like can be used. When the liquid crystal and the monomer are dissolved in a solvent, ultrasonic waves may be dissolved to uniformly dissolve the liquid crystal and the monomer.

On the other hand, an initiator is added to the solution to advance the polymerization reaction. Initiators used in the present invention include benzoyl peroxide, lauryl peroxide, o-chlorobenzoyl peroxide, o-methoxybenzoyl peroxide, t-butylperoxy-2-ethylhexanoate, t-butylperoxy Peroxides such as isobutylate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, dioctanoyl peroxide, didecanoyl peroxide, and 2,2-azobisisobuty Azo compounds such as ronitrile, 2,2-azobis (2-methylbutyronitrile), 2,2-azobis (2,4-dimethylvaleronitrile) and the like are used.

The amount of the initiator is preferably 1 to 2% by weight based on the total monomers in consideration of the effective starting efficiency. Polymerization is possible at a concentration of less than 1% by weight, but in order to obtain a degree of polymerization of 90% or more, a long time polymerization time is required, and at a concentration of more than 2% by weight, the polymerization rate is rapidly high, which may destroy spherical liquid crystals, and a polymer having a low molecular weight This is because there is a problem to form.

The solution is added to the aqueous phase containing the dispersion stabilizer and then emulsified to produce an emulsion.

The dispersion stabilizer used in the present invention is a polymer that can be dissolved in an aqueous phase, and specifically, gelatin, starch, hydroxyethyl cellulose, carboxymethyl cellulose, polyvinylpyrrolidone, polyvinyl alkyl ether, polyvinyl alcohol, poly Dimethylsiloxane / polystyrene block copolymer is included, the amount of the polymer capsule produced during the dispersion polymerization is preferably 1 to 5% by weight relative to the total reactants to the extent that the polymer capsule produced during the dispersion polymerization can suppress the deposition due to gravity or the aggregation between particles. . This is because, if it is less than 1% by weight, the stabilizing ability is drastically lowered, and if it is more than 5% by weight, not only the viscosity of the system is increased, but also the stabilizing ability is brought to equilibrium, which does not contribute to the stabilizing ability.

After adding a polymerization inhibitor to the emulsion, the suspension is polymerized to obtain a thermotropic liquid crystal polymer capsule. Suspension polymerization should be carried out only in the emulsion. In the reaction stage, since the emulsion particles are dispersed in the aqueous phase and then suspended in the aqueous phase, the reaction is carried out by the initiator in the aqueous phase, so that too small capsule particles are produced and the capsule particles are not formed efficiently. Will not. Therefore, a polymerization inhibitor is used to prevent polymerization in the water phase.                     

The type of polymerization inhibitor to be used in the present invention is not particularly limited as long as it can be dissolved in an aqueous solution. Specifically, inorganic substances such as hydroxylamine, hydrazine, sodium nitrite and potassium nitrite, hydroquinone and hydroquinone Organic substances such as monomethyl ether and pyrocatechol. The amount used is preferably 0.01% by weight or less based on the total reactants. This is because on the contrary, the starting efficiency is lowered and there is a polymerization inhibiting effect.

(3) collecting the oil-soluble active substance in the liquid crystal polymer capsule:

The method for capturing other oil-soluble active ingredients in the liquid crystal phase of the thermotropic liquid crystal polymer capsule of the present invention may use the solute co-diffusion method filed in Korean Patent No. 2000-58991. In order to introduce the oil-soluble active substance in the particles, a liquid crystal and a monomer may be melted and polymerized together with the oil-soluble active substance in the preparation of the particles, but not only by the antioxidant effect of the oil-soluble active substance, the radical polymerization reaction was performed. Even when the particles are prepared, there is a problem that high temperature reaction conditions may lower the titer of the active material. In the present invention, it is preferable to introduce the active substance into the particles by the solute co-diffusion method. Emulsion formed by dispersing the liquid crystalline polymer capsule in an aqueous solution in which a suitable concentration of surfactant is dissolved using a solute co-diffusion method, dissolving an oil-soluble active substance in an appropriate amount of solvent capable of swelling the capsule, and then emulsifying it in an aqueous solution. Particles are placed in the dispersion to collect the oil soluble active substance in the particles. Such oil-soluble active substances include retinol, retinyl acetate, retinyl palmitate, α-tocopherol, tocopherol acetate, tocopherylolinate, tocopheryl nicotinate, linoleic acid, coenzyme Q-10, resveratrol, plants Extracting essential oils.

(4) crosslinking the liquid crystal polymer capsule in which the oil-soluble active substance is collected

The liquid crystal crosslinked polymer capsule may be prepared by adding a monomer and an appropriate crosslinking agent in the preparation of the capsule to crosslink the outer polymer, but in this case, the formed polymer crosslinking network restricts the introduction of the oil-soluble active material into the particles. Preferably, it is preferable to use a postcrosslinking system using a silane group. The silane crosslinking reaction does not require a high temperature reaction condition that can reduce the titer of the active material, and is preferable for crosslinking the capsule in which the active material is collected since the silane crosslinking reaction is performed in an aqueous solution at room temperature without using an organic solvent. Silane crosslinking is also carried out in an aqueous solution, but an acid such as acetic acid, sulfonic acid or phosphoric acid or a base such as ammonia may be used as an additive to promote the crosslinking reaction.

Hereinafter, the method of the present invention will be described in more detail with reference to Examples and Comparative Examples, but the scope of the present invention is not limited to the following Examples.

<Example 1>

 Silane copolymer was used as a polymer having a functional group that can be crosslinked.

1) A silane copolymer (poly (methylmethacrylate-co-vinyl silane)) was prepared by dispersion polymerization.

First, 9 g of methyl methacrylate, 1 g of vinylsilane monomer, and 0.15 g of azobisisobutyronitrile as a fat-soluble initiator were completely dissolved in 4 ml of polyvinylpyrrolidone K-30 (molecular weight 40,000 g / mol) dispersion stabilizer in 100 ml of methanol. I was. Subsequently, the polymerization was carried out by stirring at a rate of 40 rpm for 24 hours at a temperature of 45 to 65 ℃ in a nitrogen atmosphere. After removing the unreacted material and the dispersion stabilizer using a centrifugal separator and dried in a vacuum oven for 24 hours, as a silane copolymer, a polymethyl methacrylate vinyl silane copolymer (poly (methylmethacrylate-co-vinyl silane)) ) 7.5g.

2) The liquid crystal crosslinked polymer microcapsules containing retinol as an oil-soluble active material were prepared through the following process.

7.2 g of the silane copolymer prepared above was uniformly dissolved with 8 g of cholesteryl nonanoate and 72 g of methyl methacrylate monomer while irradiating with ultrasonic waves in 20 ml methylene chloride. At this time, 1% by weight of 2,2'-azobis (2-methylbutyronitrile) relative to the monomer was added as an initiator. Then, the solution was added to an aqueous solution (polyvinyl alcohol concentration 1.0%) in which polyvinyl alcohol having a saponification degree of 87 to 89% was dissolved, and then emulsified at 5,000 rpm shear stress for 5 minutes. The emulsion prepared by emulsification was placed in a reactor heated to 60 ° C., 0.35 g of Sodium dehydronitrate was added, and then polymerized for 4 hours. After the polymerization was completed, the remaining organic solvent was evaporated under reduced pressure, filtered, washed three times with water, and then dried in a vacuum oven to obtain a powder form of cholesterol liquid crystal polymer capsules 80g.

In order to introduce retinol as an active material into the liquid crystal polymer capsules prepared above, 1 g of retinol (50C, manufactured by BASF) was completely dissolved in 20 ml of methylene chloride, and then water and ethanol mixed solution having 0.25% concentration of sodicurlauryl sulfate dissolved. After addition to 80 ml, a suspension was prepared by emulsifying for 5 minutes at a shear stress of 25,000 rpm. Then, 9g of the liquid crystal polymer capsules prepared above were dispersed in 100 ml of a water and an ethanol mixture in which 0.25% concentration of sodicurlauryl sulfate was dissolved, followed by addition of 0.02 g of a polyvinyl alcohol dispersion stabilizer. To the solution in which the liquid crystal polymer capsules were dispersed, 209,5 g of the prepared retinol suspension was added and reacted at room temperature for 4 hours. After the reaction, a small amount (0.05 g) of ammonia was added to promote the formation of the polymer crosslinked network, followed by reaction for 1 hour, and the remaining organic solvent was evaporated under reduced pressure. After repeated filtration and washing with water several times, and dried in a vacuum oven to obtain a capsule in the form of a powder.

<Example 2>

A capsule was prepared in the same manner as in Example 1, except that 1 g of coenzyme Q-10 was used as the active substance instead of retinol as the active substance.

<Example 3>

Capsules were prepared in the same manner as in Example 1, except that 2.5 g of tocopherol was used instead of retinol as the active substance.

Comparative Example 1

It was prepared in the same manner as in Example 1, except that the capsule was prepared only with the monomer without introducing a silane group and the liquid crystal polymer capsule was not crosslinked.

In other words, using methyl methacrylate and cholesteryl liquid crystal as a monomer, retinol as an active ingredient was collected to obtain 9 g capsules. As in Example 1, the crosslinking reaction was prevented from occurring by not adding the silane copolymer.

Comparative Example 2

The preparation was carried out in the same manner as in Example 1, except that the polymer particles were prepared only from monomers without introducing cholesterol liquid crystals and silane groups. That is, using only methyl methacrylate monomer which was not crosslinked without adding a liquid crystal and without adding a silane copolymer, retinol as an active ingredient was collected to obtain 9 g of capsules.

<Test Example 1>

The silane copolymer prepared by varying the amount of the polymer having a silane group according to the method of Example 1 was analyzed using gel permeation chromatography and differential scanning calorimetry. As a result, the copolymer has a molecular weight of 40000 ~ 50000g / mol, the glass transition temperature was shown in the 130 ~ 110 ℃ range. As the amount of silane introduced increases, the glass transition temperature tends to decrease. Changes in the glass transition temperature and molecular weight according to the amount of silane introduced are shown in Table 1 below. In the present invention, a copolymer in which 10% by weight of silane monomer is introduced based on the total monomers was used.

Amount of polymer having a silane group (wt%) Molecular Weight (g / mol) Glass transition temperature (℃) 0 43300 128.8 5 48400 122.8 10 50000 117.9 20 40000 114.9

In order to confirm the distribution of retinol in the particles of the liquid crystal polymer cross-linked capsules prepared in Example 1, observation was performed by confocal laser scanning microscopy. As can be seen in Figure 1 it was confirmed that the self-fluorescent retinol is uniformly distributed inside the particle. Retinol has a molecular structure similar to cholesteryl nonanonate, the liquid crystal material in capsules. As a result, the retinol mixed with the liquid crystal participates in the molecular arrangement of the liquid crystal and is immobilized and stabilized between the liquid crystals. In the photograph of FIG. 1, all particles do not appear to exhibit fluorescence incorporating retinol because the particles are not in focus because they are different from each other. As a result of this observation, it was confirmed that the retinol was well distributed in the liquid crystal phase inside the polymer particles.

<Formulation example and stability test>                     

<Formulation Example 1, Comparative Formulation Examples 1, 2, 3> Gel Type

In order to confirm the stabilizing ability of the prepared capsule, a solubilized formulation in the form of a transparent gel having a composition of Table 2 was prepared. The unit of content is weight percent. Same as below.

ingredient Formulation Example 1 Comparative Formulation Example 1 Comparative Formulation Example 2 Comparative Formulation Example 3 glycerin 5 5 5 5 Propylene glycol 4 4 4 4 Liquid crystal capsule Example 1 5 - - - Comparative Example 1 5 - - Comparative Example 2 - - 5 - Unencapsulated retinol - - - 5 ethanol 10 10 10 10 Sodium Polyacrylate 0.5 0.5 0.5 0.5 antiseptic Quantity Quantity Quantity Quantity Purified water to 100 to 100 to 100 to 100

Unencapsulated retinol for the preparation of Comparative Formulation Example 3 used commercially available 50C (BASF). Same as below.

The viscosity of the formulation was about 4,000 cps. The viscosity was measured at 30 ° C., 12 rpm using Brookfield (LVDVII +).

<Stability Test 1>

After storing the prepared samples in the oven at room temperature and 40 ℃, respectively, the sample was taken after a certain period of time to measure the amount of the remaining active material using liquid chromatography. The results are shown in Table 3. As can be seen in Table 3, the retinol present in the liquid crystal capsule in the solubilized formulation has excellent stability.

capsule Storage temperature (℃) Initial concentration retention rate (%) 1 day later 7 days later 14 days later 28 days later Formulation Example 1 Room temperature 100 100 100 100 40 100 100 100 99 Comparative Formulation Example 1 Room temperature 100 100 100 98 40 100 99 96 95 Comparative Formulation Example 2 Room temperature 100 98 99 91 40 92 80 69 54 Comparative Formulation Example 3 Room temperature 98 95 88 63 40 89 65 52 33

<Formulation Example 2, Comparative Formulation Examples 4, 5, 6> Lotion

In order to examine the stabilizing effect in the emulsifier type, lotions were prepared according to the content (unit: wt%) of Table 4 below.

 Each of the oil phase and the water phase in the composition of Table 4 was completely dissolved at 70 ℃, emulsified at 7,000 rpm for 5 minutes to prepare a lotion in the form of an opaque gel. The viscosity of the lotion is about 2,500 cps.

ingredient Formulation Example 2 Comparative Formulation Example 4 Comparative Formulation Example 5 Comparative Formulation Example 6 Stearic acid 2 2 2 2 Cetyl alcohol 2 2 2 2 Lanolin alcohol 2 2 2 2 Liquid paraffin 7 7 7 7 Cyclomethicone 5 5 5 5 Polyoxyethylene monooleic acid ester 2 2 2 2 Preservatives, Antioxidants Quantity Quantity Quantity Quantity glycerin 3 3 3 3 Propylene glycol 5 5 5 5 Triethylamine One One One One Liquid crystal capsule Example 1 8 - - - Comparative Example 1 - 8 - - Comparative Example 2 - - 8 - Unencapsulated retinol - - - 8 Sodium Polyacrylate 0.15 0.15 0.15 0.15 Purified water to 100 to 100 to 100 to 100

<Stability Test 2>

The prepared samples were stored at room temperature and 40 ° C., respectively, and after a certain period of time, samples were taken to measure the amount of the remaining active substance using liquid chromatography. The results are shown in Table 5. As can be seen in Table 5, even in the suspension emulsion type (lotion type), the retinol present in the liquid crystal capsule has excellent stability. However, when the non-crosslinked liquid crystal capsule is used, the stability is somewhat reduced. It is believed that the surfactant added during formulation preparation induces liquid crystal outflow of retinol. However, in the case of using a crosslinked liquid crystal capsule, since the effect is essentially blocked, a result showing excellent stability was obtained. Through this it can be confirmed the superiority of the system for stabilizing the double crosslinking capsule.

capsule Storage temperature (℃) Initial concentration retention rate (%) 1 day later 7 days later 14 days later 28 days later Formulation Example 2 Room temperature 100 100 100 100 40 100 100 98 97 Comparative Formulation Example 4 Room temperature 100 100 99 97 40 99 96 96 93 Comparative Formulation Example 5 Room temperature 99 97 97 93 40 95 75 63 49 Comparative Formulation Example 6 Room temperature 99 92 85 61 40 88 66 55 38

<Formulation Example 3> Cream

In order to confirm the stability of the active material collected in the prepared liquid crystal polymer capsules, a cream was prepared in the composition of Table 6 below. The preparation was the same as in Formulation Example 2.

ingredient Formulation Example 3 Comparative Formulation Example 7 Comparative Formulation Example 8 Comparative Formulation Example 9 Beads wax 2 2 2 2 Stearyl alcohol 5 5 5 5 Stearic acid 8 8 8 8 Squalane 10 10 10 10 Propylene Glycol Monostearate 3 3 3 3 Polyoxyethylene cetyl ether One One One One Preservatives and Antioxidants Quantity Quantity Quantity Quantity Propylene glycol 8 8 8 8 glycerin 4 4 4 4 Triethylamine One One One One Liquid crystal capsule Example 1 2 - - - Comparative Example 1 - 2 - - Comparative Example 2 - - 2 - Unencapsulated retinol - - - 2 Purified water to 100 to 100 to 100 to 100

<Stability Test 3>

After storing the prepared samples in the oven at room temperature and 40 ℃, respectively, the sample was taken after a certain period of time to measure the amount of the remaining active material using liquid chromatography. The results are shown in Table 7. Like the lotion formulation, the cream formulation also showed that the cross-linking of the capsules contributed to statin retinol stabilization.

capsule Storage temperature (℃) Initial concentration retention rate (%) 1 day later 7 days later 14 days later 28 days later Formulation Example 3 Room temperature 100 100 99 99 40 100 100 99 98 Comparative Formulation Example 7 Room temperature 100 99 99 98 40 100 97 94 94 Comparative Formulation Example 8 Room temperature 100 98 97 91 40 96 77 68 54 Comparative Formulation Example 9 Room temperature 98 93 78 60 40 85 67 51 40

<Formulation Examples 4 and 5 and Stability Test 4>                     

In order to confirm the degree of stabilization of other useful components in this system, coenzyme-Q10 and tocopherol were prepared in Examples 2 and 3 and applied to Formulation Example 3 to confirm the stability thereof. To make a cream with a composition as shown in Table 8 to say the formulation examples 4, 5.

ingredient Formulation Example 4 Formulation Example 5 Beads wax 2 2 Stearyl alcohol 5 5 Stearic acid 8 8 Squalane 10 10 Propylene Glycol Monostearate 3 3 Polyoxyethylene cetyl ether One One Preservatives and Antioxidants Quantity Quantity Propylene glycol 8 8 glycerin 4 4 Triethylamine One One Liquid crystal capsule Example 2 2 - Example 3 - 2 Purified water to 100 to 100

The stability test was carried out in the same manner as in the stability test 3.

As shown in Table 9, it was confirmed that the present cross-linked liquid crystal polymer capsule has an excellent effect in stabilization of other useful components.

capsule Storage temperature (℃) Initial concentration retention rate (%) 1 day later 7 days later 14 days later 28 days later Coenzyme-Q10 Containing Capsule of Example 2 Room temperature 100 99 99 99 40 100 99 97 95 Tocopherol-containing capsules of Example 3 Room temperature 100 100 99 98 40 100 98 96 94

To summarize the above results, it can be seen that the retinol in the simple polymer particles is not in contact with the external environment due to the swelling of the particles by moisture, oil, surfactant, etc. in the cosmetic formulation, and does not show excellent stability. It can be seen that the prepared liquid crystal polymer capsules showed better stability in the formulation than other systems by immobilizing the retinol between the liquid crystals by a liquid crystal having a molecular structure similar to retinol in the polymer particles. Complementing such a liquid crystal polymer capsule in the present invention was prepared a liquid crystal cross-linked polymer capsule that can see the double stabilization effect by the polymer cross-linked network of the outer shell with the liquid crystal effect in the particle. The liquid crystal crosslinked polymer capsule prepared in Example 1 significantly reduces the swelling of the particles due to moisture or oil in the formulation by the crosslinked outer polymer particles with the internal liquid crystal effect immobilizing the retinol, thereby more effectively external It is expected to block stimulation.

As described above, the liquid crystal crosslinked polymer capsule according to the present invention is a novel technology having considerable differentiation from other general approaches, and thus it is judged to be an original technology capable of completely stabilizing the useful active material. In addition, since the liquid crystal material is encapsulated in a polymer crosslinked network, the liquid crystal behavior can be exhibited as it is, so it is not only applicable to the visual effects of the liquid crystal but also to the smart drug delivery system having temperature dependence. It can be applied to various materials such as electronic materials, paint industry and paper industry using the inherent behavior of liquid crystals by utilizing stimulus blocking properties and excellent compatibility with general inorganic materials.

Claims (10)

(1) polymerizing a polymer having a crosslinkable functional group by polymerizing a monomer having a crosslinkable functional group and a monomer capable of radical polymerization; (2) A polymer having a thermotropic liquid crystal, a hydrophobic monomer and a crosslinkable functional group prepared in step (1) was uniformly dissolved in an organic solvent, and this solution was emulsified in an aqueous solution in which a dispersion stabilizer of an appropriate concentration was dissolved. Thereafter, adding an initiator and a polymerization inhibitor to polymerize to prepare a thermotropic liquid crystal polymer capsule; (3) collecting the oil-soluble active substance in the capsule; (4) A method for producing a liquid crystal crosslinked polymer capsule, comprising crosslinking a liquid crystal polymer capsule in which the oil-soluble active substance is collected. The method according to claim 1, wherein the monomer having a functional group capable of crosslinking in step (1) is used in an amount of 0.1 to 50% by weight based on the total weight of the polymer. The method of claim 2, wherein the monomer having a crosslinkable functional group is trichlorovinylsilane, trimethoxyvinylsilane, triethoxyvinylsilane, vinyltriisooxysilane, vinyltri-t-butoxysilane, vinyl tree Phenoxysilane, vinyltriacetoxysilane, vinyltri (isobutoxy) silane, vinyltri (2-methoxyethoxy) silane, 8-oct-1-enyltrichlorosilane, 8-oct-1-enyltri Ethoxysilane, 8-oct-1-enyltriethoxysilane, 6-hex-1-enyltrichlorosilane, 6-hex-enyltriethoxysilane, characterized in that the liquid crystal crosslinked polymer capsule Manufacturing method. The method of claim 1, wherein in the step (2), the liquid crystal is a cholesterol and cholesteryl derivative, which is used in an amount of 0.1 to 50% by weight based on the total capsule particles. The liquid crystal of claim 4, wherein the cholesteryl derivative is selected from the group consisting of cholesteryl octanoate, cholesteryl nonanoate, cholesteryl oleyl carbonate, and cholesteryl isostearyl carbonate. Method for producing a crosslinked polymer capsule. The active substance in step (3) of claim 1 is retinol, retinyl acetate, retinyl palmitate, tocopherol, tocopheryl acetate, tocopheryl linoleate, tocopheryl nicotinate, linoleic acid, coenzyme Q-10 , Resveratrol or a method for producing a liquid crystal crosslinked polymer capsule, characterized in that the plant extract essential oil. A liquid crystal crosslinked polymer capsule produced by the method of any one of claims 1 to 6. Cosmetic composition containing the liquid crystal crosslinked polymer capsule manufactured by the method of any one of Claims 1-6. delete Retinol, retinyl acetate, retinyl palmitate, tocopherol, tocopheryl acetate, tocopheryl linoleate, tocopheryl nicotinate, linoleic acid, coenzyme Q-10, resveratrol or plant extract essential oils as active substances A method for stabilizing the active substance by preparing a capsule prepared by the method of any one of claims 1 to 6 using.

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