CN116806141A

CN116806141A - Method for stabilizing active ingredient by using mineral material

Info

Publication number: CN116806141A
Application number: CN202180088384.5A
Authority: CN
Inventors: 廉准皙; 赵恩哲; 林志媛; 奉晓琎; 郑琁阿; 朴鲁镇; 沈愚先
Original assignee: LG Household and Health Care Ltd; Industry University Cooperation Foundation IUCF HYU
Current assignee: Industry University Cooperation Foundation IUCF HYU; LG H&H Co Ltd
Priority date: 2020-12-29
Filing date: 2021-12-28
Publication date: 2023-09-26

Abstract

The present invention relates to stabilization of active ingredients using mineral materials. In the present invention, the active ingredient can be stably supported by using the mineral material, and the microcapsule prepared by the preparation method of the present invention has no environmental problem when discharged to the natural because the encapsulating ingredient is the same as the soil ingredient, thus being free from the problem of microplastic.

Description

Method for stabilizing active ingredient by using mineral material

Technical Field

The present invention relates to a method for stabilizing an active ingredient using a mineral material. More specifically, the present invention relates to a technique for stabilizing an active ingredient which can be free from the problem of microplastic, and to a technique for stably supporting an active ingredient using a mineral material other than microplastic.

Background

Encapsulation is a general term for a form in which an active ingredient is trapped in a substance corresponding to the outer wall for effective delivery of the active ingredient. The capsule can perform accurate delivery with good purpose even with small amount of effective components, thereby reducing side effects, maintaining stability of effective components, and reducing cost related problems. Thus, capsules find application in a variety of forms and purposes in the industrial field, such as targeted delivery of drugs in the medical/pharmaceutical field; the stability of the fragrance in the sanitary article is maintained and the fragrance is emitted at the point in time desired by the user; stability maintenance and skin delivery from external stimuli (e.g., light, heat, etc.) of functional substances in the cosmetic field; and in agricultural and food fields, stability maintenance of pesticides and nutrients and the like, enhancement of absorption efficiency and the like.

However, the international organization indicates that microcapsules are one of the causes of pollution of microplastic (small plastic pieces having a diameter of 5mm or less) which do not degrade and accumulate in nature and thus may induce serious environmental pollution. According to the ECHA report (2019), when an inorganic substance or a biodegradable polymer substance is used as it is as a substance capable of getting rid of the problem of microplastic, a substance designed so as to be immediately degradable, called a readily biodegradable (readily biodegradable), is selected. However, capsules prepared from inorganic materials such as silica, which are not materials in the microplastic category, have a problem that they are liable to be broken due to tension or impact generated when they are not resistant to drying. In addition, if the capsule is prepared from a natural polymer, there is a problem in that the active ingredient in the capsule is eluted due to the inherent fine porosity of the material, and thus the stability of the capsule cannot be maintained. If crosslinking is used to reduce fine porosity and improve stability, there is a problem that degradability is reduced and biodegradability is not provided. In addition, if an ester bond-introduced substance is used to be easily degraded, there is a problem that the dosage form cannot withstand severe conditions (pH change, temperature change) and degradation occurs before use, and thus the solution has been unknown or totally absent so far.

Silica, which is an inorganic material, is a substance that does not affect living bodies and is safe, and is widely used as a material for pharmaceutical, cosmetic, household goods, and the like. The silica occupies most of the soil component, which is a substance constituting the earth, and is a substance constituting the cell wall of diatoms, which are microorganisms, and thus is a safe substance. Therefore, although research on encapsulation of an active ingredient using silica has been paid attention, silica is likely to break due to tension generated during drying unlike a polymer as described above, and thus, additional research is required.

Prior art literature

Non-patent literature

1:ANNEX XV RESTRICTION REPORT,PROPOSAL FOR A RESTRICTION；SUBSTANCE NAME(S):intentionally added microplastics,DATE:22August 2019

Disclosure of Invention

Technical problem

The present inventors have studied for developing microcapsules using mineral materials as inorganic materials, and have found that when a continuous phase containing an emulsifier is mixed with a dispersed phase containing an encapsulated component and an active ingredient, and then microcapsules containing the active ingredient are prepared by a hardening reaction of the encapsulated component, the encapsulated component is identical to a soil component, and thus there is no environmental problem when discharged to the natural environment, and completed the present invention.

Accordingly, an object of the present invention is to provide a method for preparing microcapsules having high versatility, natural affinity and stability, microcapsules prepared thereby, and washing products comprising the microcapsules.

Means for solving the problems

The invention provides a preparation method of microcapsules, which comprises the following steps:

a step of mixing a continuous phase containing an emulsifier with a dispersed phase containing an encapsulating ingredient and an active ingredient to prepare an emulsion; and

a step of encapsulating the emulsion,

the emulsifier includes at least one selected from the group consisting of anionic surfactants, cationic surfactants, amphoteric surfactants and nonionic surfactants,

the encapsulating component includes at least one selected from the group consisting of a silica precursor, a titania precursor, and a zirconia precursor.

In addition, the present invention provides a microcapsule prepared by the aforementioned microcapsule preparation method, and having a particle diameter of 0.1 to 1,000 μm.

In addition, the present invention provides a washing product comprising the aforementioned microcapsules.

In addition, the present invention provides the use of microcapsules for preparing a washing product, the microcapsules being prepared by the aforementioned method of preparing microcapsules and having a particle size of 0.1 to 1,000 μm.

Effects of the invention

The present invention provides a method for stabilizing active ingredients by using mineral materials.

In the present invention, the active ingredient can be stably supported by using the mineral material, and the microcapsule prepared by the preparation method of the present invention has no environmental problem when discharged to the natural because the encapsulating ingredient is the same as the soil ingredient, thus being free from the problem of microplastic. In addition, the microcapsule prepared by the preparation method of the present invention has a dense (dense) structure of the outer wall of the capsule, and thus can prevent dissolution of the active ingredient.

Drawings

Fig. 1 illustrates a method of preparing microcapsules of the present invention.

Fig. 2 shows the results of morphological confirmation of microcapsules prepared in examples of the present invention using a scanning electron microscope (Scanning Electron Microscopy) (SEM). Specifically, a shows an SEM photograph of example 8, B shows an enlarged photograph of example 8, C shows a broken section photograph of example 8, and D shows a broken section photograph of example 40.

Fig. 3 shows the results of particle size confirmation of microcapsules prepared in example 8 of the present invention using Mastersizer 3000.

Fig. 4 shows the results of confirming the amount of fragrance stored in capsules according to time in the presence of an emulsifier in an environment of 50 c for the microcapsules prepared in examples 8 and 40 of the present invention.

Detailed Description

The invention relates to a preparation method of microcapsules, which comprises the following steps:

a step of encapsulating the emulsion,

The constitution of the present invention will be specifically described below.

In the present invention, the microcapsule refers to a fine particle surrounding a liquid, solid or paste-like active ingredient, and may have a particle diameter of 0.1 to 1,000 μm. The microcapsule can physically and chemically protect the active ingredient from the external environment, and can regulate the release of the active ingredient.

In the present invention, the microcapsules can be prepared by the steps of:

a step of mixing a continuous phase containing an emulsifier with a dispersed phase containing an encapsulating ingredient and an active ingredient to prepare an emulsion (hereinafter, emulsion preparation step); and

and a step of encapsulating the emulsion (hereinafter, an encapsulating step).

In the present invention, the emulsion preparation step may be a step of mixing the continuous phase and the dispersed phase to prepare an emulsion.

In the present invention, the continuous phase, as the aqueous phase, may contain an emulsifier.

In one embodiment, as the solvent of the continuous phase, solvents commonly used in the art may be used, and specifically, distilled water may be used.

In a specific example, the emulsifier is a substance that serves as a skeleton so that an encapsulated ingredient to be described later can be converted into an outer wall of the capsule. As such an emulsifier, an emulsifier generally used in the art may be used, and specifically, one or more selected from the group consisting of anionic surfactants, cationic surfactants, amphoteric surfactants, and nonionic surfactants may be used.

The cationic surfactant may be one or more selected from the group consisting of a trimethylalkylammonium salt, a dialkyldimethylammonium salt, and an alkylbenzylmethylammonium salt, the anionic surfactant may be one or more selected from the group consisting of a sodium fatty acid, a monoalkylsulfate, an alkylpolyoxyethylene sulfate, an alkylbenzenesulfonate, and a monoalkylphosphate, the amphoteric surfactant may be one or more selected from the group consisting of an alkylsulfonyl betaine, an alkylcarboxy betaine, and the like, and the nonionic surfactant may be one or more selected from the group consisting of a fatty alcohol, a polyoxyethylene alkyl ether, a fatty acid sorbitan ester, a fatty acid diethanolamine, and an alkyl monoglyceride ether.

Preferably, the emulsifier may be a cationic surfactant, and specifically, cetyltrimethylammonium bromide (CTAB) or cetyltrimethylammonium chloride (CTAC) may be used. The above-mentioned CTAB or CTAC not only promotes hydrolysis and reaction at the interface due to the effect caused by emulsification but also due to the presence of amine groups within the structure, so that more uniform reaction can be induced and dense microcapsules can be prepared.

In one specific example, the content of the emulsifier is not particularly limited, and may include 0.00001 to 10 parts by weight, 0.0001 to 10 parts by weight, 0.0002 to 5 parts by weight, 0.0005 to 2 parts by weight, or 0.002 to 1.2 parts by weight with respect to the total weight of the emulsion (100 parts by weight). If the content of the emulsifier is less than 0.00001 parts by weight, there is a problem that emulsification cannot be performed, and if it exceeds 10 parts by weight, the content of the emulsifier becomes excessive, and the active ingredient in the capsule may be eluted.

In the present invention, the dispersed phase is an oil phase containing an encapsulating ingredient and an active ingredient.

In one specific example, the solvent of the dispersed phase is not particularly limited as long as it is a solvent that is not miscible with the continuous phase. When distilled water is used as the solvent of the continuous phase, a solvent selected from the group consisting of Hydrocarbon (Hydrocarbon) series solvents can be used as the solvent of the dispersed phase; a solvent comprising an Ether group (Ether group); a solvent comprising an Ester group (Ester group); a solvent comprising a Ketone group (Ketone group); a solvent comprising Benzene (Benzene); haloalkane (haloakane) series solvents; and one or more of the group consisting of Silicone (Silicone) series solvents.

The above Hydrocarbon (hydro carbon) series solvent may be selected from compounds of linear or nonlinear structure such as Pentane (Pentane), hexane (Hexane), cyclohexane (Cyclohexane), heptane (Heptane), octane (Octane), isododecane (isoodecane) and Dodecane (Dodecane), the solvent containing an Ether group (Ether group) may be selected from Ethyl Ether (Ethyl Ether), butyl Ether (Butyl Ether) and Methyl t-Butyl Ether (Methyl-t-Butyl Ether), and the solvent containing an Ester group (Ester group) may be selected from Ethyl acetate (Ethyl acetate), butyl acetate (Butyl acetate) and Ethyl butyrate (Ethyl Butyl acetate). In addition, the solvent containing a Ketone group may be methyl ethyl Ketone (Methyl ethyl Ketone), the solvent containing Benzene (Benzene) may be selected from Benzene (Benzene), toluene (tolene) and Xylene (Xylene), the Haloalkane (haloakane) series solvent may be selected from dichloromethane (dichloromethane), dichloroethane (dichlorethane), chloroform (Chloroform) and carbon tetrachloride (Carbon tetrachloride), and the Silicone (Silicone) series solvent may be selected from polydimethylsiloxane (Dimethicone) and Cyclomethicone (Cyclomethicone).

In the present invention, the encapsulating component is a component constituting the outer wall of the capsule, and can be converted into a mineral material at the time of the encapsulating reaction. The above-mentioned encapsulation reaction may be a hydrolysis reaction.

In a specific example, a mineral material precursor may be used as the encapsulating component, and the mineral material precursor may be one or more selected from the group consisting of a silica precursor, a titania precursor, and a zirconia precursor.

In one specific example, the mineral material precursor may include one or more compounds selected from the group consisting of compounds represented by the following chemical formulas 1 to 4.

[ chemical formula 1]

[ chemical formula 2]

[ chemical formula 3]

[ chemical formula 4]

In the above chemical formulas 1 to 4, a may be silicon, titanium or zirconium,

R ₁ to R ₄ Each independently may be hydrogen or an alkyl group having 1 to 8 carbon atoms which is substituted or unsubstituted at the terminal with a functional group which may include an amine, a hydroxyl group, an amide, a carboxyl group, a vinyl group, an epoxy group, a phenyl group, a mercapto group, or the like.

In one specific example, the silica precursor may include one or more selected from the group consisting of tetramethyl orthosilicate, tetraethyl orthosilicate (Tetraethyl orthosilicate), tetrapropyl orthosilicate, tetrabutyl orthosilicate, methyltrimethoxysilicate, dimethyldimethoxy silicate, trimethylmethoxy silicate, trimethylethoxy silicate, butyltrimethoxysilicate, N-propyltrimethoxysilane, N-octyltrimethoxysilane, aminopropyl trimethoxysilicate, phenyltrimethoxysilane (Phenyltrimethoxysilane), 3-mercaptopropyltrimethoxysilane, and methyldimethoxy silane, the titanium oxide precursor may include one or more selected from the group consisting of titanium methoxide, titanium ethoxide, and titanium butoxide, and the zirconium oxide precursor may include one or more selected from the group consisting of zirconium methoxide, zirconium ethoxide, and zirconium butoxide.

In one embodiment, the content of the encapsulating ingredient is not particularly limited, and may be 0.001 to 30 parts by weight, 0.01 to 25 parts by weight, or 0.1 to 20 parts by weight with respect to the total weight of the emulsion (100 parts by weight). If the content of the encapsulating component is less than 0.001 parts by weight, there is a possibility that even if the encapsulating reaction occurs, the outer wall of the capsule is formed thin and cannot be maintained, and if it exceeds 30 parts by weight, the distinction between the dispersed phase and the continuous phase becomes blurred, and there is a possibility that the capsule cannot be formed.

In the present invention, the active ingredient is a substance whose activity is desired to be maintained by the resulting capsule, and the active ingredient can then express its activity by disruption of the outer wall of the capsule. When the active ingredient is liquid at room temperature, it may be substituted for the dispersed phase as a solvent. As these active ingredients, one or more selected from the group consisting of perfumes, ultraviolet blockers, dyes, catalysts, antioxidants and drugs can be used.

In one embodiment, where the active ingredient is a perfume, the present invention may provide a perfumed product comprising microcapsules. As the above-mentioned fragrance-emitting product, a fragrance-emitting spray, a fragrance liquid product, a cleanser, a face-washing agent, a body product, a hair product or a washing product may be included. The above washing products refer to products to be treated on laundry, and may include, but are not limited to, washing agents, fiber softeners, perfuming agents, laundry deodorants, dry cleaners, detergents, bleaching agents, and the like.

When the active ingredient is an ultraviolet blocker, the present invention can provide an ultraviolet blocking cosmetic composition comprising microcapsules. As the above ultraviolet blocker component, for example, titanium dioxide (TiO ₂ ) Inorganic ultraviolet blockers such as zinc oxide (ZnO), silicate, or talc; or organic ultraviolet blockers such as isoamyl p-methoxycinnamate, octyl methoxycinnamate, ethylhexyl triazone, oxybenzone, hexyl diethylaminooxybenzoyl benzoate, octyl octocrylene Lin Shuiyang (octocrylene octyl salicylate), butyl methoxydibenzoylmethane, octyl salicylate, benzophenone, anthranilate, and the like.

In addition, when the active ingredient is a functional substance or a poorly soluble substance, the microcapsule of the present invention can be provided as a carrier for improving the stability of the functional substance or the poorly soluble substance. As the above functional substance or poorly soluble substance, an antioxidant such as retinol or resveratrol; or poorly soluble substances such as cholesterol or ceramide; cold sensory stimulating substances such as menthol, vanillyl butyl ether, and the like.

In one embodiment, the content of the active ingredient is not particularly limited, and may be 0.001 to 20 parts by weight, 0.01 to 15 parts by weight, or 1 to 10 parts by weight with respect to the total weight of the emulsion (100 parts by weight).

In one embodiment, the content of the encapsulating ingredient may be 0.5 to 3 times the content of the active ingredient. If the content of the encapsulating ingredient exceeds 3 times that of the active ingredient, there is a possibility that the inter-particle aggregation phenomenon occurs to cause gelation, and if it is less than 0.5 times, there is a possibility that phase separation occurs, so that the content ratio is preferably maintained at 0.5 to 3 times.

In addition, in one embodiment, the content of the encapsulating ingredient and the active ingredient may be 35 parts by weight or more, specifically 10 to 35 parts by weight, 11 to 35 parts by weight, or 15 to 30 parts by weight, relative to the total weight (100 parts by weight) of the emulsion. If the content of the encapsulating ingredient and the active ingredient exceeds 35 parts by weight, the active ingredient is difficult to stabilize, but there is a possibility that the inter-particle aggregation phenomenon occurs to cause gelation. In addition, if the content of the encapsulating ingredient and the active ingredient is less than 10 parts by weight, phase separation may occur.

In the emulsion preparation step of the present invention, an emulsion can be prepared by mixing the aforementioned continuous phase and dispersed phase.

In one embodiment, the content of the dispersed phase may be 35 parts by weight or less, 10 to 35 parts by weight, 11 to 35 parts by weight, or 15 to 30 parts by weight, based on the mixed weight (100 parts by weight) of the dispersed phase and the continuous phase.

In one embodiment, the emulsion preparation step may be performed by adding a dispersed phase in the continuous phase, and may be performed with stirring.

In one embodiment, the stirring may be performed at 20 to 30 ℃, or at room temperature, at 1 to 16,000RPM, 5 to 13,000rpm, or 10 to 10,000 rpm. In addition, the stirring time may vary depending on the volume of the emulsion prepared.

In the present invention, the encapsulating reaction step is a step of preparing microcapsules by subjecting the emulsion prepared in the emulsion preparation step to an encapsulating reaction.

As shown in fig. 1, a stable microcapsule containing an active ingredient can be prepared by a hardening reaction (or curing reaction) of an encapsulated ingredient. Specifically, the encapsulating component contains an alkoxy group and is thus initially mixed in the dispersed phase as a core material, but if hydrolysis occurs at the emulsion interface, the encapsulating component becomes hydrophilic and stacks at the interface. In the process, a curing reaction occurs to form a solid outer wall.

In one embodiment, the time interval between the emulsion preparation step and the encapsulation reaction step may be from 1 hour to 14 days.

In one embodiment, the encapsulation reaction step may be performed under weakly acidic conditions. The above-mentioned weakly acidic condition may be pH 2 to 5 or pH 2 to 4. Under the weak acidic condition, the capsule outer wall with a compact structure can be prepared. If the pH exceeds the above range, particles (capsules) of the desired micro-size may not be formed, and even if particles are formed, the outer wall may be thin or porous particles may be formed, so that the active ingredient may not be stably supported in the capsules and may be easily eluted.

In one embodiment, the encapsulation reaction for preparing the microcapsules may be carried out at 20 to 30 ℃ or room temperature for 10 minutes to 48 hours. When the temperature is raised to promote the reaction, fine particles (capsules) are not formed, and even if particles are formed, the thickness of the outer wall may be thin or porous particles may be formed, so that it is preferable to adjust the reaction temperature and time as described above.

In one specific example, the above-mentioned encapsulation reaction may be performed in a state where the emulsion is allowed to stand without stirring. Specifically, the present invention can form a dense-structured capsule outer wall by performing an encapsulation reaction in a state where the emulsion is left to stand without increasing the reaction rate.

In one embodiment, the encapsulation reaction may be performed more than 1 time, specifically 2 to 3 times. The secondary encapsulation reaction can be performed by a method of adding an encapsulating ingredient to the emulsion having completed the primary encapsulation reaction to perform the reaction. The encapsulating component used in the secondary encapsulating reaction may be the same as the encapsulating component used in the primary reaction, or a different type of encapsulating component may be used.

When the above-mentioned encapsulation reaction is performed twice, microcapsules having double walls can be prepared, and when prepared as double walls, the content of silica increases, the capsules themselves become thick, and thus active ingredients can be stably preserved even in a severe environment.

In addition, the present invention relates to microcapsules prepared by the aforementioned method of preparing microcapsules.

The microcapsules of the present invention may have an average particle size of 0.1 to 1,000 μm, 0.1 to 100 μm, 0.5 to 80 μm or 1 to 5 μm. When the average particle diameter of the above microcapsules is less than 0.1 μm, the amount of the active ingredient carried in the capsules is too small, and therefore even if the microcapsules are applied, too small an amount is expressed, and therefore there is a possibility that the effect thereof cannot be exhibited. In addition, when the average particle diameter exceeds 1000 μm, there is a problem that microcapsules are easily broken due to tension generated by drying of the capsules composed of a mineral material.

In addition, the outer wall thickness of the capsule may be 0.01 to 1 μm.

In addition, the present invention relates to a washing product comprising the aforementioned microcapsules.

In one embodiment, the wash product may include a wash lotion, a fiber softener, a perfuming agent, a laundry deodorant, a dry-cleaning agent, a soil release agent, a bleach, and the like.

In one embodiment, the microcapsules may be present in the wash product in an amount of 0.5 to 20 parts by weight or 1 to 10 parts by weight relative to the total weight.

In addition, the present invention relates to the use of microcapsules for the preparation of a washing product, said microcapsules being prepared by the aforementioned microcapsule preparation method and having a particle size of 0.1 to 1,000 μm.

Mode for carrying out the invention

The present invention will be described in detail with reference to examples. The following examples are merely illustrative of the present invention, and the scope of the present invention is not limited to the following examples. The present embodiment is provided for complete disclosure of the present invention and to fully illustrate the scope of the invention to those of ordinary skill in the art to which the present invention pertains, and the present invention is defined only by the scope of the claims.

Examples

Hereinafter, the raw materials used in examples, comparative examples and experimental examples were purchased and used from commercial cosmetic raw material enterprises or reagent enterprises.

Examples 1 to 10 preparation of microcapsules using encapsulated ingredients

Microcapsules were prepared according to the compositions and contents of table 1 below. First, an emulsifier (CTAB) was dissolved in distilled water to prepare a continuous phase. The encapsulated ingredients and perfume (superfume) are thoroughly mixed together to prepare a dispersed phase. The dispersed phase was added to the above continuous phase and stirred at 8,000rpm to prepare an emulsion, and the encapsulation reaction was performed under weakly acidic conditions.

On the other hand, in comparative example 1, an emulsion for emulsifying a fragrance was prepared according to the composition and content of table 1.

First, a continuous phase in which an emulsifier is dissolved in distilled water is prepared. Then, a fragrance as a dispersed phase was added to the above continuous phase and stirred at 8,000rpm to prepare an emulsion.

The microcapsule prepared according to the present invention was used after being stabilized at 30℃under 50% humidity constant temperature and humidity for 24 hours, except for experimental example 6.

TABLE 1

Experimental example 1 evaluation of fragrance intensity after washing

In order to confirm the aftertaste potentiating properties of the microcapsules prepared in examples 1 to 10 and comparative example 1, washing evaluation was performed.

First, 4 commercially available cotton towels (30 cm. Times.20 cm) (100% cotton, song Yue towel (Inc.) were used as the test fibers. The above-mentioned cotton towel was repeatedly washed 5 times with a washing machine using a standard amount of a general washing lotion, and then dehydrated (one-time washing).

Based on 100 parts by weight of the entire composition, 5 parts by weight of the microcapsules prepared in examples 1 to 10 and comparative example 1 were put into an aqueous solution containing 5 parts by weight of CTAB and immediately treated on a cotton towel. Specifically, washing (secondary washing) was performed by using a household full-automatic washing machine, setting the water amount to 45L, rinsing for 10 minutes, and dehydrating for 5 minutes. The cotton towel was then dried at a temperature of 25℃with a humidity of 30% for 12 hours.

At this time, three time points (immediately after washing, after drying, and after rubbing) were set, and functional evaluation was performed by 20 skilled panelists aged 20 to 40 to evaluate fragrance intensity. The "immediately after washing" means the time point when the secondary washing is completed, the "after drying" means the time point after drying in a constant temperature and humidity room for 12 hours, the "after rubbing" means the time point after rubbing by folding the above-mentioned dried cotton towel twice in the transverse direction, folding it into four equal parts, holding it in the transverse direction with both hands after rotating it by 90 degrees, and then positioning the cotton towel between the hands, gently rubbing it like a circle, repeating it three times.

For the above flavor intensity, the cotton towel based on the untreated microcapsules was given 0 point, the lowest 0 point to the highest 5 points were assigned, and the above was repeated 3 times or more, and the average was taken.

The results of performing functional evaluation after washing treatment of the cotton towel after preparing the microcapsule-containing composition are shown in table 2 below.

< evaluation criteria >

0 point: the fragrance hardly remains.

5, the method comprises the following steps: the fragrance remains much.

TABLE 2

As shown in table 2 above, it was confirmed that the microcapsules of the present invention exhibited flavor emission properties as compared with comparative example 1. In particular, it was confirmed that when a silica precursor was used as the encapsulating component, the strength of the flavor after rubbing was 3 or more, and the flavor emission was high.

It is estimated that the reason why the aroma after drying is excellent is that the result occurs due to the fact that a part of large microcapsule particles are broken during drying to emit aroma.

Examples 11 to 20 preparation of microcapsules according to the kind of emulsifier

Microcapsules were prepared according to the compositions and contents of table 3.

First, a continuous phase in which an emulsifier is dissolved in distilled water is prepared. At the same time, TEOS and fragrance (fragrance) are thoroughly mixed to prepare a disperse phase. Then, the dispersed phase was added to the continuous phase and stirred at 8,000rpm to prepare an emulsion, and an encapsulation reaction was performed under weakly acidic conditions.

TABLE 3

Experimental example 2 evaluation of fragrance intensity after washing

In order to confirm the aftertaste potentiating properties of the microcapsules prepared in examples 11 to 20, washing evaluation was performed. The aftertaste enhancement properties of these microcapsules were carried out by the method of experimental example 1.

The results of the above functional evaluation are shown in Table 4 below.

< evaluation criteria >

0 point: the fragrance hardly remains.

5, the method comprises the following steps: the fragrance remains much.

TABLE 4

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As shown in table 4 above, it was confirmed that the residual fragrance after rubbing was excellent when the microcapsules containing the fragrance oil were used.

It was confirmed that the microcapsules prepared using the cationic emulsifier were high in aftertaste and decreased in aftertaste in the order of nonionic and anionic emulsifiers. This means that, in the case of the preparation using a cationic emulsifier, the encapsulation reaction uniformly occurs at the interface, and therefore the flavor oil has high preservation power and high aftertaste after rubbing.

Examples 21 to 22 preparation of surface modified microcapsules

Microcapsules were prepared according to the compositions and contents of table 5.

First, a continuous phase in which an emulsifier is dissolved in distilled water is prepared. At the same time, TEOS and silica precursor and fragrance are thoroughly mixed to prepare a dispersed phase. Then, the dispersed phase was added to the continuous phase and stirred at 8,000rpm to prepare an emulsion, and an encapsulation reaction was performed under weakly acidic conditions.

TABLE 5

Experimental example 3 evaluation of fragrance intensity after washing

In order to confirm the aftertaste potentiating properties of the microcapsules prepared in examples 21 to 22, washing evaluation was performed.

The aftertaste enhancement properties of these microcapsules were carried out by the method of experimental example 1.

The results of the above functional evaluation are shown in Table 6 below.

< evaluation criteria >

0 point: the fragrance hardly remains.

5, the method comprises the following steps: the fragrance remains much.

TABLE 6

	Example 8	Example 21	Example 22
				Immediately after washing	2.23	2.18	2.11
After drying	1.75	1.88	1.64
				After friction	3.85	3.98	3.88

As shown in table 6 above, it was confirmed that the aftertaste was maintained even when the surface of the microcapsule was modified with a functional group.

Examples 23 to 32 preparation of microcapsules sized according to the emulsifier content

Microcapsules were prepared according to the compositions and contents of table 7.

First, a continuous phase in which an emulsifier is dissolved in distilled water is prepared. At the same time, each TEOS and fragrance were thoroughly mixed to prepare a dispersed phase. Then, the dispersed phase was added to the continuous phase and stirred at 8,000rpm to prepare an emulsion, and an encapsulation reaction was performed under weakly acidic conditions.

In particular, examples 31 and 32 in order to prepare smaller-sized microcapsules, after the emulsion preparation process described above, a Tip ultrasonic homogenizer (Tip homogenizer) was treated for 5 minutes, and then an encapsulation reaction was performed under weakly acidic conditions.

TABLE 7

Experimental example 4 measurement of microcapsule particle size

The particle diameters of the microcapsules prepared in examples 23 to 32 were measured.

The particle size of the particles was measured using a Matersizer 3000 (Malvern, UK).

It was confirmed that when 0.0001% of the emulsifier was used (example 23), phase separation occurred due to non-emulsification, but when 0.0005% or more was used, emulsification was started to prepare microcapsules.

In particular, FIG. 3 is a measurement result of particle size of the microcapsule prepared in example 8, and it was confirmed that the microcapsule had an average particle diameter of 1.5. Mu.m.

Experimental example 5 evaluation of fragrance intensity after washing

In order to confirm the aftertaste potentiating properties of the microcapsules prepared in examples 23 to 32, washing evaluation was performed.

The results of the above functional evaluation are shown in Table 8 below.

< evaluation criteria >

0 point: the fragrance hardly remains.

5, the method comprises the following steps: the fragrance remains much.

TABLE 8

As shown in table 8 above, it was confirmed that the smaller the size of the microcapsules, the greater the aftertaste. It is judged that the larger the particles, the less the capsule is able to withstand the tension acting on the surface of the capsule, breaking, and thus the aftertaste cannot be maintained. In addition, it was confirmed that when 0.1 wt% or more of the emulsifier was used, the particle size was hardly changed and the aftertaste was similar.

In addition, it was confirmed that in the case of preparing particles of a small size by ultrasonic homogenizer (sonicator) treatment, aftertaste was reduced from 0.5 μm.

Examples 33 to 38 and comparative examples 2 to 3. Preparation of microcapsules according to the composition of the microcapsule shell

Microcapsules were prepared according to the compositions and contents of table 9.

First, a continuous phase in which an emulsifier is dissolved in distilled water is prepared. At the same time, TEOS and fragrance are thoroughly mixed to prepare a disperse phase. Then, the dispersed phase was added to the continuous phase and stirred at 8,000rpm to prepare an emulsion, and an encapsulation reaction was performed under weakly acidic conditions.

TABLE 9

From the results of confirming the 28-day change at room temperature in terms of the TEOS content, it was confirmed that when 0.1 wt% of TEOS was used, phase separation occurred due to the failure of normal production of capsules, and when 30 wt% or more was used, gelation (gelling) started, and when 50 wt% or more was used, the problem of gel formation occurred.

Examples 39 to 43 preparation of microcapsules composed of double walls

Microcapsules were prepared according to the compositions and contents of table 10.

First, a continuous phase in which an emulsifier is dissolved in distilled water is prepared. At the same time, each TEOS and fragrance were thoroughly mixed to prepare a dispersed phase. Then, the dispersed phase was added to the continuous phase and stirred at 8,000rpm to prepare an emulsion, and an encapsulation reaction was performed under weakly acidic conditions. Thereafter, TEOS was added in an amount of 1 to 9%, followed by stirring at 400rpm, to further carry out the encapsulation reaction.

TABLE 10

Experimental example 6 evaluation of fragrance intensity after washing

In order to confirm the aftertaste potentiating properties of the microcapsules prepared in examples 39 to 43, washing evaluation was performed. The microcapsules were placed in 5% ctab solution before washing and stored at 50 ℃ for 1 month.

The aftertaste enhancement properties of these microcapsules were carried out by the method of experimental example 1. The results of the above functional evaluation are shown in Table 11 below.

< evaluation criteria >

0 point: the fragrance hardly remains.

5, the method comprises the following steps: the fragrance remains much.

TABLE 11

	Example 39	Example 40	Example 41	Example 42	Example 43	Example 8
							Immediately after washing	2.23	2.25	2.05	2.05	2.21	2.2
After drying	1.2	1.23	1.3	1.25	1.3	1.2
							After friction	2.62	3.15	3.12	3.25	3.24	2.45

As shown in table 11 above, it was confirmed that the larger the content of silica contained in the shell of the microcapsule, the more the perfume was maintained in a severe environment (an environment containing a high content of surfactant at a high temperature). It is judged that this is a result of the thickening of the capsule itself.

Fig. 2D is an SEM photograph of the microcapsule prepared in example 40, and it was confirmed that the surface was smooth and the thickness was also increased from 22nm to 38nm, as compared with fig. 2C corresponding to example 8.

Experimental example 7 evaluation of microcapsules

To confirm whether the outer wall (shell) of the microcapsule was normally prepared, the microcapsule prepared in example 8 was put into ethanol, and after a sufficient time to extract perfume, centrifugal separation was performed using a centrifuge (centrifuge). Thereafter, water was added thereto, and then the mixture was freeze-dried to obtain silica particles in the form of fine powder, and the form of microcapsules was confirmed by a scanning electron microscope (Scanning Electron Microscopy).

Fig. 2 shows the results of confirming the microcapsule morphology. As shown in fig. 2A and 2B, it was confirmed that the outer wall of the mineral material was formed on the surface of the microcapsule.

In addition, in order to confirm the stability of the microcapsules, 5 parts by weight of the microcapsules prepared in examples 8 and 40, respectively, were put into an aqueous solution containing 5 parts by weight of CTAB based on 100 parts by weight of the entire composition, and then stored in a chamber at 50 ℃ for 4 weeks. Samples were taken at 1 day, 2 days, 5 days, 7 days, 10 days, 14 days, 20 days, and 28 days, the microcapsules were filtered with a 0.45um syringe filter (syringe filter), then placed in ethanol, and the absorbance of the perfume remaining inside the microcapsules was measured by an ultraviolet-visible spectrophotometer (UV-Vis spectrophotometer) using an ultrasonic homogenizer (sonicator), thereby measuring the actual concentration.

Fig. 4 shows the results of confirming the stability of the microcapsules.

As shown in fig. 4, it was confirmed that the fragrance was maintained at about 80% in the case of example 40 at 50 ℃ for 4 weeks. From this, it was indirectly confirmed that the microcapsules can maintain the perfume for a long period of time even under severe conditions containing a large amount of surfactant.

Examples 44 to 55 preparation of microcapsules according to pH

Microcapsules were prepared according to the compositions and contents of table 12 below. First, an emulsifier is dissolved in distilled water to prepare a continuous phase. At the same time, the encapsulating ingredient and perfume (perfume) are thoroughly mixed to prepare a dispersed phase. The dispersed phase was added to the above continuous phase and stirred at 8,000rpm to prepare an emulsion.

Thereafter, the pH of the emulsion was adjusted using 1.0N HCl and 1.0N NaOH as shown in Table 12, and then an encapsulation reaction was performed.

TABLE 12

The results of the preparation of the microcapsules confirmed that, in the case where the pH was less than 2 and 6 or more, the microcapsules were not prepared and phase separation occurred during the preparation. At a pH of 2 to 5.5, the emulsified state is maintained after the encapsulation reaction has been carried out.

Experimental example 8 evaluation of fragrance intensity after washing

In order to confirm the aftertaste potentiating properties of the capsules according to the pH of the microcapsules prepared in examples 46 to 52, washing evaluations were performed. The microcapsules were placed in a 5% CTAB solution before washing and stored at a temperature of 50 ℃ for 1 month.

The aftertaste enhancement properties of these microcapsules were carried out by the method of experimental example 1. The results of the above functional evaluation are shown in Table 13 below.

< evaluation criteria >

0 point: the fragrance hardly remains.

5, the method comprises the following steps: the fragrance remains much.

TABLE 13

As shown in table 13 above, it was confirmed that the perfume retention of the microcapsules prepared at pH 2 to 4 was high.

This means that in order to minimize defects (defects) in the manufacture of microcapsules, it is necessary to prepare them in a suitable pH environment, which means that they must be prepared at a pH of 2 to 4 in order to prepare microcapsules capable of preserving the active ingredient for a long period of time.

Industrial applicability

Claims

1. A method of preparing microcapsules comprising:

a step of encapsulating the emulsion,

2. The method for producing microcapsules according to claim 1, wherein,

the emulsifier is cationic surfactant.

3. The method for producing microcapsules according to claim 1, wherein,

the emulsifier is Cetyl Trimethyl Ammonium Bromide (CTAB) or Cetyl Trimethyl Ammonium Chloride (CTAC).

4. The method for producing microcapsules according to claim 1, wherein,

the content of the emulsifier is 0.00001 to 10 parts by weight relative to the total weight of the emulsion.

5. The method for producing microcapsules according to claim 1, wherein,

the encapsulating ingredient includes one or more selected from the group consisting of compounds represented by the following chemical formulas 1 to 4:

[ chemical formula 1]

[ chemical formula 2]

[ chemical formula 3]

[ chemical formula 4]

In the above chemical formulas 1 to 4, A is silicon, titanium or zirconium,

R ₁ to R ₄ Each independently is hydrogen or an alkyl group having 1 to 8 carbon atoms which is substituted or unsubstituted at the end with a functional group,

the above functional groups include amine, hydroxyl, amide, carboxyl, vinyl, epoxy, phenyl or mercapto groups.

6. The method for producing microcapsules according to claim 1, wherein,

the silica precursor includes one or more selected from the group consisting of tetramethyl orthosilicate, tetraethyl orthosilicate, tetrapropyl orthosilicate, tetrabutyl orthosilicate, methyltrimethoxysilicate, butyltrimethoxysilicate, N-propyltrimethoxysilane, N-octyltrimethoxysilane, aminopropyltrimethoxysilicate, phenyltrimethoxysilane, and 3-mercaptopropyltrimethoxysilane,

the titanium oxide precursor includes one or more selected from the group consisting of titanium methoxide, titanium ethoxide and titanium butoxide,

the zirconia precursor includes one or more selected from the group consisting of zirconium methoxide, zirconium ethoxide, and zirconium butoxide.

7. The method for producing microcapsules according to claim 1, wherein,

the content of the encapsulating ingredient is 0.001 to 30 parts by weight relative to the total weight of the emulsion.

8. The method for producing microcapsules according to claim 1, wherein,

the effective components comprise more than one selected from the group consisting of perfume, ultraviolet blocker, dye, catalyst, antioxidant and medicine.

9. The method for producing microcapsules according to claim 1, wherein,

the content of the encapsulating ingredient is 0.5 to 3 times that of the active ingredient.

10. The method for producing microcapsules according to claim 1, wherein,

the content of the encapsulating component and the active component is 35 parts by weight or less relative to the total weight of the emulsion.

11. The method for producing microcapsules according to claim 1, wherein,

the encapsulation reaction is carried out at a pH of 2 to 5.

12. A microcapsule prepared by the method for preparing a microcapsule according to any one of claims 1 to 11, and having a particle diameter of 0.1 to 1,000 μm.

13. A washing product comprising the microcapsule of claim 12.

14. Use of microcapsules for the preparation of a washing product, the microcapsules being prepared by the method of preparation of microcapsules according to any one of claims 1 to 11 and having a particle size of 0.1 to 1,000 μm.