JP2006008564A - Microcapsules and compositions containing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a salt-soluble microcapsule that is insoluble in water but dissolves or swells in an aqueous electrolyte solution, and uses a release function based on this feature to make cosmetics, hygiene products, fragrance, external preparation, fiber treatment Provided is a composition that can be suitably used for various uses such as a hair preparation and a hair treatment agent.
[MEANS FOR SOLVING PROBLEMS] The microcapsules of the present invention are characterized by using a salt-soluble polymer as a membrane material. The salt-soluble polymer used is preferably a sulfobetaine-based polymer that is insoluble in water and dissolves at a salt concentration of 0.01 to 10% or more.
The composition of the present invention is characterized by containing the above microcapsules. Examples of the composition include a cosmetic composition, a hygiene product composition, a fragrance composition, and a fiber treatment composition. Etc.
[Selection figure] None

Description

  TECHNICAL FIELD The present invention relates to a microcapsule having a polymer compound whose dissolved state changes with a slight change in electrolyte concentration in water as a membrane material, and more specifically, salt solubility that is insoluble in water and dissolves or swells in an aqueous electrolyte solution. It is a microcapsule, and it can be suitably used for various compositions such as cosmetics, hygiene products, fragrances, external preparations, fiber treatment agents, hair treatment agents, etc. by utilizing the release function based on this feature. The present invention relates to a microcapsule that can be produced and a composition containing the same.

  Conventionally, microcapsules have been applied and developed in various fields such as cosmetics, hygiene products, fragrances, external preparations, fiber treatment agents, hair treatment agents for the purpose of protecting and releasing active ingredients and functional ingredients.

  In order to release active ingredients and functional ingredients that are core substances from microcapsules, most means are to release microcapsules by breaking them, and to release them from microcapsule pores, and there are not many means to dissolve and release membrane materials. Is.

Examples of those that break the microcapsules and release the core substance include a membrane obtained by preparing a matrix from a gel-forming agent, an anionic polymer and an active ingredient, and dropping the matrix into an aqueous chitosan solution. A microcapsule having an average diameter of 0.1 to 5 mm made of a matrix containing at least one active ingredient (for example, see Patent Document 1) is known.
However, this microcapsule has a problem that the active ingredient may not be completely released without being completely destroyed.

  In order to release the core material from the microcapsule pores, for example, a ceramic microporous material containing a fragrance is supported on a cellulose fine powder, and the ceramic microporous material is used as a medium. An aromatic fabric formed by adhering to a fabric is known (for example, see Patent Document 2). Further, as a device for dissolving a microcapsule and releasing a fragrance, a fragrance included using a cyclodextrin (for example, Patent Documents 3 and 4) are known.

However, the microcapsule using the ceramic microporous material described in Patent Document 2 has a problem that the fragrance is always released, and the fragrance may be weakened until it is actually used after production. In the microcapsules described in Patent Documents 3 and 4, cyclodextrin is used, so if the blending amount is increased in order to produce an effect, stickiness may occur at the time of use. There is a problem that it is necessary to mix them.
Japanese translation of PCT publication No. 2003-506323 (Claims, Examples, etc.) JP-A-5-163676 (Claims, Examples, etc.) JP 2001-316219 A (Claims, Examples, etc.) Japanese Patent Laid-Open No. 10-120541 (Claims, Examples, etc.)

  The present invention intends to solve the above-mentioned problems of the prior art, and includes changes in electrolyte concentration during use, specifically, for example, 0.5% by mass or more of salt. Salt-sensitive release that can release components such as physiologically active substances, active ingredients, fragrances, drugs, and pigments that are expressed by contact with salt water such as human body fluids such as sweat, tears, and urine, and concentration of aqueous electrolyte solutions. It aims at providing the microcapsule which uses the salt-soluble polymer compound which has a property as a film | membrane material. Furthermore, it aims at providing compositions, such as cosmetics, hygiene goods, and a fragrance | flavor, using this microcapsule.

  As a result of intensive studies to solve the above-described conventional problems, the present inventors can achieve this by using a polymer having specific physical properties as a membrane material, and using the polymer as a phase separation method, spray cooling method, liquid The inventors have found that microcapsules can be prepared by a microencapsulation method such as an intermediate drying method or an interfacial polymerization method, and have completed the present invention.

That is, the present invention resides in the following (1) to (5).
(1) A microcapsule comprising a salt-soluble polymer as a membrane material.
(2) The microcapsule according to (1) above, wherein the salt-soluble polymer is insoluble in water and dissolves at a salt concentration of 0.01 to 10%.
(3) The microcapsule according to (1) or (2) above, wherein the salt-soluble polymer is a sulfobetaine polymer.
(4) A composition comprising the microcapsule according to any one of (1) to (3) above.
(5) The composition according to (4) above, wherein the composition is any one of a cosmetic composition, a sanitary product composition, a fragrance composition, and a fiber treatment composition.

  According to the present invention, changes in electrolyte concentration during use, specifically contact with salt water such as human body fluids such as sweat, tears, and urine containing 0.5% by mass or more of salt, Preparation of a microcapsule using a salt-soluble polymer with a salt-sensitive release property that can release components such as physiologically active substances, active ingredients, fragrances, drugs, and pigments that are expressed by concentration of aqueous electrolyte solution And a microcapsule that can be stably contained in various uses such as cosmetics, hygiene products, fragrances, external preparations, fiber treatment agents, hair treatment agents, and the like, and compositions containing the same.

Hereinafter, embodiments of the present invention will be described in detail.
The microcapsule of the present invention is characterized by using a salt-soluble polymer as a film material, and the composition of the present invention is characterized by containing the microcapsule.
Specifically, the microcapsule of the present invention includes, for example, a physiologically active substance, an active ingredient, a fragrance, a drug, and a dye as a core substance, and a salt-soluble polymer such as a sulfobetaine salt-sensitive polymer compound. The composition of the present invention comprises a microcapsule stably in a composition such as cosmetics, hygiene products, and fragrances.

In the present invention, the salt-soluble polymer to be used is not particularly limited as long as it is a salt-soluble polymer, but it is preferably insoluble in water from the viewpoint of easy salt solubility, usability, and ease of manufacture. A salt-soluble polymer that dissolves at a salt concentration of 0.01 to 10% is desirable, and more preferably, a sulfobetaine having these properties (insoluble in water and soluble at a salt concentration of 0.01 to 10%) A salt-sensitive polymer compound is desirable.
The sulfobetaine-based salt-sensitive polymer compound used is a sulfobetaine group-containing vinyl monomer from the viewpoint of desirably controlling the affinity with the core substance and the water solubility of the polymer compound in the capsule preparation described below. A copolymer having (A) and a hydrophobic group-containing vinyl monomer (B) as a constitutional unit and having a salt sensitivity is desirable.

  The sulfobetaine group-containing vinyl monomer (A) to be used is a monomer having both an anionic sulfonic acid group or a salt thereof and a cationic group, and the cationic group includes an amino group, A secondary amino group, a tertiary amino group, a quaternary ammonium group, etc. can be illustrated, and these can select and use 1 or more types of monomers.

As said monomer (A) to be used, the compound shown by the following general formula (I) is mentioned, for example.

  The compound of the above general formula (I) can be synthesized by sulfobetainization of a tertiary amino group-containing vinyl monomer. Sulfobetainization includes the tertiary amino group-containing monomer and a halosulfonate such as 2-bromoethanesulfonate, or a sultone such as 1,3-propane sultone and 1,4-butane sultone, etc. However, in the present invention, the reaction with a sultone is desirable from the viewpoint that the reaction proceeds promptly and that no salt is by-produced.

  Further, as the tertiary amino group-containing monomer, specifically, dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, dimethylaminobutyl (meth) acrylate, diethylaminoethyl (meth) acrylate, Examples include dimethylaminoethyl (meth) acrylamide, dimethylaminopropyl (meth) acrylamide, dimethylaminobutyl (meth) acrylamide, and diethylaminoethyl (meth) acrylamide.

The hydrophobic group-containing vinyl monomer (B) to be used is not particularly limited, but those represented by the following general formula (II) or a macromonomer containing a hydrophobic polymer such as a silicone macromonomer are suitable. Yes, these can be used alone or in combination of two or more.

  Specific examples of the compound represented by the general formula (II) include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, t-butyl (meth) acrylate, hexyl ( (Meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, octyl (meth) acrylate, lauryl (meth) acrylate, methyl (meth) acrylamide, ethyl (meth) acrylamide, propyl (meth) acrylamide, butyl (meth) ) Acrylamide, t-butyl (meth) acrylamide, hexyl (meth) acrylamide, octyl (meth) acrylamide, lauryl (meth) acrylamide, benzyl (meth) acrylate, and the like.

In the present invention, the sulfobetaine-based salt-sensitive polymer compound preferably used is a copolymer of the sulfobetaine group-containing vinyl monomer (A) and the hydrophobic group-containing vinyl monomer (B) by a production method described later. The copolymerization ratio of each component of the sulfobetaine group-containing vinyl monomer (A) and the hydrophobic group-containing vinyl monomer (B) can be applied for the purpose of the present invention. From the viewpoint of expressing salt sensitivity, the mass ratio [B] / [A] of the monomer (B) to the monomer (A) is preferably 0.01 to 5, more preferably 0. 0.03 to 3 is desirable.
When the ratio [B] / [A] is outside the range of 0.01 to 5, the salt sensitivity sufficient to be applied to the object of the present invention can be obtained even if it cannot be dissolved in the salt aqueous solution or is dissolved. It may not be possible.

In the present invention, it is preferable that a copolymerizable vinyl monomer (C) is further used as a constituent component in order to further exert a salt-sensitive function.
The vinyl monomer (C) copolymerizable with the sulfobetaine group-containing vinyl monomer (A) and the hydrophobic group-containing vinyl monomer (B) is not particularly limited, but is synthesized. Can be used for purposes such as controlling the solubility of the copolymer and adjusting the capsule membrane-forming ability and the salt-sensitive release function, such as vinyl monomers having a hydrophilic functional group and crosslinkable monomers. The body etc. can be used.

Examples of vinyl monomers having a hydrophilic functional group that can be used include (meth) acrylic acid (salt), (meth) acrylamide methanesulfonic acid (salt), and 2- (meth) acrylamido-2-methylpropane. Those having an anionic group such as sulfonic acid (salt), methanesulfonic acid (meth) acrylate, trimethylaminoethyl chloride (meth) acrylate, trimethylaminopropyl chloride (meth) acrylate, trimethylaminobutyl chloride (meth) acrylate, Triethylaminoethyl (meth) acrylate chloride, trimethylaminoethyl (meth) acrylamide chloride, trimethylaminopropyl (meth) acrylamide chloride, trimethylaminobutyl (meth) acrylamide chloride, triethylaminoethyl chloride (meth) acrylamide Having a quaternary ammonium group such as dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, dimethylaminobutyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylamide, dimethyl Those having a tertiary amino group such as aminopropyl (meth) acrylamide, dimethylaminobutyl (meth) acrylamide, diethylaminoethyl (meth) acrylamide, or having a polyoxyalkylene chain represented by the following general formula (III) And those having an amide group such as (meth) acrylamide, those having a hydroxyl group such as hydroxyethyl (meth) acrylate, vinylpyrrolidone, vinylpyridine and the like. .

Examples of the crosslinkable monomer that can be used include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and 1,4-butanediol di (meth) acrylate. 1.6-hexanediol di (meth) acrylate, N, N′-methylenebisacrylamide, divinylbenzene, and the like. As these vinyl monomers (C), one compound can be used, or two or more compounds can be used in combination.
As a preferred vinyl monomer (C), a polyoxyalkylene chain represented by the above general formula (III) is used since the solubility of the copolymer can be easily controlled without impairing the salt-sensitive function. It is desirable to have it.

In the present invention, when the vinyl monomer (C) is preferably used, the sulfobetaine group-containing vinyl monomer (A), the hydrophobic group-containing vinyl monomer (B), and the vinyl monomer ( C) is copolymerized by the production method described later, and the copolymerization ratio of these components is such that the salt sensitivity that can be applied for the purpose of the present invention is further expressed. The mass ratio [B] / [A] of the monomer (B) and the monomer (A) is 0.01 to 5, and the monomer (C) and the monomer (A) The mass ratio [C] / [A] is 0.01 to 2, more preferably [B] / [A] is 0.03 to 3, and [C] / [A] is 0.01 to 1. desirable.
If these [B] / [A] and [C] / [A] are outside the above ranges (0.01 to 5, 0.01 to 2), they may or may not be dissolved in the salt aqueous solution. In some cases, the salt sensitivity sufficient for the purpose of the present invention cannot be obtained.

  In the present invention, the molecular weight of the resulting sulfobetaine-based salt-sensitive polymer compound (copolymer) is not particularly limited, but is usually 1,000 to 1,000,000 in terms of mass average molecular weight, and preferably facilitates the preparation of microcapsules. From this point, the one in the range of 10,000 to 500,000 is desirable.

In the present invention, the production method of the sulfobetaine-based salt-sensitive polymer compound [components (A) and (B), components (A) to (C)] is not particularly limited, and solution polymerization, emulsion polymerization, It can manufacture by using various methods, such as precipitation polymerization.
When performing solution polymerization, a polymerization solvent for dissolving a plurality of monomers having different properties is used. Examples of such solvents include methanol, ethanol, isopropanol, ethyl acetate, toluene, methyl ethyl ketone, and cyclohexanone. used. The polymerization initiator is not particularly limited, and for example, peroxides such as benzoyl peroxide and potassium persulfate, and azo compounds such as azobisisobutyronitrile and azobiscyanovaleric acid can be used. Furthermore, the usage-amount of an initiator is not specifically limited, Usually, it is 0.1-10 mol% with respect to the total amount of monomers. The polymerization temperature varies depending on the polymerization method and the type of initiator used, but is usually 50 to 100 ° C. The polymerization time is 2 to 10 hours.

In the present invention, the sulfobetaine-based salt-sensitive polymer compound preferably used is the above-described polymerization of the constituent monomers (A) and (B), preferably a copolymerizable vinyl monomer (C) as described above. The monomer represented by the general formula (I) among the monomers (A) can be produced by polymerization according to the method, etc., and the tertiary amino group-containing vinyl monomer as a precursor Is then copolymerized with the monomer (B) and further with (C), and then the tertiary amino group in the copolymer is converted to sulfobetaine.
In particular, a vinyl monomer having a tertiary amino group is selected as part or all of the monomer (C), and the monomer (A) is a sulfobetaine-forming reaction of the tertiary amino group-containing monomer. In the copolymer, the tertiary amino group is partially subjected to sulfobetainization reaction so that the constituent ratio in the finally obtained polymer compound is desired. Thus, the desired sulfobetaine-based salt-sensitive polymer compound having a desired composition ratio can be obtained.

As a core substance used in the present invention, it is used for various applications such as cosmetics such as physiologically active substances, active ingredients, fragrances, drugs, pigments, hygiene products, fragrances, external preparations, fiber treatment agents, hair treatment agents, etc. Any component can be used as long as it is contained in the microcapsule.
In the microcapsule of the present invention, the above-mentioned components are contained in a total amount of 0.1 to 70% by mass (hereinafter simply referred to as “%”) in the total amount of the microcapsule. It is desirable to contain 5 to 50%, more preferably 1.0 to 30%.
If the content is less than 0.1%, the effect is not exhibited. On the other hand, if the content exceeds 70%, there is a possibility that inconveniences such as incapability of microencapsulation occur.

The average particle size of the microcapsules is not particularly limited and can be appropriately selected according to the purpose, and is preferably 0.01 μm to 1000 μm, more preferably 0.1 to 700 μm.
When the average particle size of the microcapsule is less than 0.01 μm, it is difficult to prepare the microcapsule. On the other hand, when it exceeds 1000 μm, it is difficult to uniformly disperse in the preparation and the appearance may be deteriorated. is there.

  The method for preparing the microcapsule of the present invention is not particularly limited, and a known microencapsulation method or the like can be employed. In the case of the present invention, the phase separation method, the orifice method, and the spray cooling method are preferable from the viewpoint of efficient microencapsulation and stable protection of the core substance. The target microcapsules can be more efficiently prepared by the preferred methods described below.

  The phase separation method is a method in which a salt-soluble polymer such as a sulfobetaine-based salt-sensitive polymer compound, which is a membrane material, is dissolved in an aqueous solution containing a salt, and then the core material is dispersed to adjust the desired particle size. To do. Thereafter, purified water or the like is added dropwise to lower the salt concentration in the system, whereby the sulfobetaine salt-sensitive polymer compound is phase-separated and adsorbed around the core substance to prepare microcapsules.

  In the orifice method, an aqueous solution in which a salt-soluble polymer such as a sulfobetaine-based salt-sensitive polymer compound is dissolved outside the double tube nozzle, and a solution containing a core substance is flowed inside to form droplets by vibration or the like. Then, the solution is dropped into an aqueous solution capable of depositing a salt-soluble polymer such as a sulfobetaine-based salt-sensitive polymer compound to prepare a microcapsule.

  The spray cooling method is a method of spraying water phase small components in which a core substance is dispersed in an aqueous solution in which a salt-soluble polymer such as a sulfobetaine-based salt-sensitive polymer compound is dissolved, cooling and solidifying it, and then collecting water. This is a method for obtaining a microcapsule in a state. In addition, the microcapsules can be dried and used by low temperature drying or freeze drying.

  The sulfobetaine-based salt-sensitive polymer compound having the above-described structure used in the present invention is characterized in that it is insoluble in water and dissolves or swells in an aqueous electrolyte solution, and a hydrophobic monomer is incorporated as a copolymerization monomer. In this case, since it has excellent affinity with hydrophobic organic substances, it is easily adsorbed at the interface with the hydrophobic core substance in the electrolyte aqueous solution. As a result, it can be obtained by known microencapsulation methods such as phase separation method, orifice method, spray cooling method In addition, it is possible to efficiently prepare microcapsules using the polymer as a membrane material, and to change the concentration of the electrolyte during use, specifically, for example, sweat, tears containing 0.5% by mass or more of salt, A salty sensation that can release components such as physiologically active substances, active ingredients, fragrances, drugs, and pigments by contact with salt water such as urine and other human body fluids and by concentration of aqueous electrolyte solution. So that the microcapsules with a release property is obtained.

The microcapsules of the present invention include emulsions, cosmetics, lotions, cosmetics, creams, gel preparations, cosmetic compositions such as hair treatment agents, external preparations such as pharmaceuticals and quasi-drugs, softeners, It can be suitably contained in compositions for various uses such as a care agent, a fiber treatment agent composition such as a wrinkle prevention spray, a sanitary product composition such as a paper diaper, and a fragrance composition.
The microcapsules of the present invention can be suitably contained in each of the above compositions, but the content in this case varies depending on the use of each composition, but is 0.1% in the total amount of the composition. -20% is preferable, More preferably, 0.3-10% is desirable.
If the content is less than 0.1%, the effect of the microcapsule of the present invention is not sufficiently exhibited. On the other hand, if the content exceeds 20%, no significant improvement in the effect is observed.

  In the present invention configured as described above, a component such as a physiologically active substance, an active ingredient, a fragrance, a drug, and a dye is used as a core substance, and the film material is composed of a salt-soluble polymer. It is possible to efficiently and easily release components such as physiologically active substances, active ingredients, and fragrances by contact with salt water such as human body fluids such as sweat, tears, urine and the like, and concentration of aqueous electrolyte solution. Can be obtained, and can be stably contained in compositions for various uses such as cosmetics, hygiene products, fragrances, external preparations, fiber treatment agents, hair treatment agents and the like.

  EXAMPLES Next, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited to the following Example etc.

First, a method for preparing a microcapsule using a sulfobetaine-based salt-sensitive polymer compound as a membrane material, a method for preparing a preparation containing the microcapsule, each evaluation method, and the like will be described below.
(1) Method for preparing microcapsules using a sulfobetaine salt-sensitive polymer compound as a membrane material After adding a predetermined amount of purified water and an inorganic salt into a dissolution tank equipped with a stirrer, sulfobetaine salt sensitivity An aqueous phase was prepared by adding a polymer compound and heating and dissolving to a temperature at which the polymer was dissolved.
Subsequently, the core substance described later was added to the aqueous phase while stirring to prepare a dispersion containing the core substance. This dispersion was microencapsulated by a conventional phase separation method, orifice method, or spray cooling method to obtain a microcapsule using a sulfobetaine salt-sensitive polymer compound as a membrane material.

(2) Composition examples of cosmetics, hygiene products, fragrances and softeners Specific compositions of lotion, emulsion, gel, disposable diapers, fragrances and softeners are shown below, but are not limited to these compositions. Further, the production method is not particularly limited, and it is blended by a general preparation method. In addition, a compounding unit is the mass% and the whole quantity is 100 mass%.

<Lotion>
Deacylated gellan gum 0.03
Calcium chloride 0.01
Dipropylene glycol 4.0
Concentrated glycerin 4.0
Ethanol 3.0
Trimethylglycine 0.1
Arbutin 0.5
Rose water 0.1
Sodium benzoate 0.2
Microcapsule 1.0
Purified water balance

<Emulsion>
Bentonite 0.3
Hexaglyceryl monostearate 1.2
Diglyceryl monolaurate 0.5
Sorbitan sesquioleate 3.0
Dipotassium glycyrrhizinate 0.1
Licorice flavonoids 0.05
Isopropyl myristate 2.0
Decamethylcyclopentasiloxane 3.0
Plant-based squalane 6.0
Jojoba oil 1.5
Rosehip oil 0.5
Stearyl alcohol 2.0
Concentrated glycerin 5.0
Dipropylene glycol 2.0
Carboxyvinyl polymer 0.12
Methyl paraoxybenzoate 0.3
Propyl paraoxybenzoate 0.1
Oxidized coenzyme A 0.2
Triisopropanolamine 0.1
Ethanol 2.0
Microcapsule 5.0
Purified water balance

<Gel>
Polyoxyethylene hydrogenated castor oil (60EO) 0.5
Oil-soluble licorice extract 0.1
Ethanol 7.0
Concentrated glycerin 1.5
Dipropylene glycol 3.0
Methyl paraoxybenzoate 0.1
Propyl paraoxybenzoate 0.1
Transparent soluble xanthan gum 0.1
Acrylic acid / alkyl methacrylate copolymer 0.3
Triisopropanolamine 0.18
Citric acid 0.05
Sodium citrate 0.05
Perfume appropriate amount Microcapsule 0.5
Creatinine 0.1
Purified water balance

<Air freshener>
Carrageenan 2.0
Malic acid 0.01
Polyoxyethylene lauryl ether (9EO) 5.0
Polyoxyethylene lauryl ether (15EO) 11.0
Fragrance 4.0
Butylhydroxytoluene 0.1
Microcapsule 0.5
Ethylene glycol 2.0
Sodium chloride 0.3
Purified water balance

<Absorbent sheet for disposable diapers>
After 0.7 g of the absorbent polymer and 1.0 g of microcapsules were uniformly dispersed between ^two crush pulp sheets (7 cm × 15 cm, 200 g / m ² ), the whole was wrapped with a nonwoven fabric to prepare a paper diaper.

<Softener>
N, N-distearoyloxyethyl-N-methyl, N-hydroxyethylammonium sulfate 16.5
Polyoxyethylene-modified silicone (CF1188) 4.0
Polyoxyethylene isododecyl alcohol 2.0
Isothiazolone liquid trace hydrochloric acid trace fragrance appropriate amount microcapsule 7.0
Purified water balance

(3) Measuring method of average particle diameter of microcapsule It measured with the phase-contrast microscope.
(4) Evaluation method of perfume retention of microcapsules The preparation was added with 2 g to a 3 cm diameter petri dish with the microcapsules uniformly dispersed with a stirrer. From the odor after standing at room temperature for 30 minutes, the perfume retention of the microcapsules was evaluated according to the following evaluation criteria.
Perfume retention criteria for microcapsules:
◎: Almost unsatisfactory ○: Slightly felt ×: Just as strong as the fragrance with the same weight as the fragrance in the microcapsule

(5) Solubility of microcapsules and fragrance release test Evaluate the release of the core substance by the salt sensitivity of the microcapsules prepared by the following evaluation method by visual observation and microscope (magnification: x10 to 200x). did.
Evaluation methods:
After completion of the perfume retention evaluation, a 2% NaCl aqueous solution was added to the petri dish after standing for 30 minutes and gently stirred. The odor intensity after 1 minute was compared with the odor immediately before the addition of the 2% NaCl aqueous solution, and the salt-sensitive release property was evaluated according to the following evaluation criteria.
Evaluation criteria for dissolution or swelling of microcapsules and fragrance release during use:
A: The microcapsule is easily dissolved or swollen, and the aroma is remarkably increased. ○: The microcapsule is slightly dissolved or hardly swelled, but the aroma is slightly increased. X: The aroma is changed without the microcapsule being dissolved or swollen. No

[Examples 1 to 9 and Comparative Examples 1 and 2]
Hereinafter, preparation examples of microcapsules using various salt-sensitive polymers as membrane materials and compositions (cosmetics, hygiene products, fragrances) using the microcapsules will be described in detail. Moreover, the salt-sensitive polymer used in Examples 1 to 9 was prepared according to the following Production Example 1.

(Production Example 1)
Add 155.1 g of ethanol to a 1000 mL separable flask equipped with a stirrer, reflux condenser, thermometer, monomer addition port, initiator addition port and nitrogen introduction tube, and start heating in a 85 ° C hot water bath. At the same time, nitrogen introduction was started from the nitrogen introduction tube. Meanwhile, in a 300 mL beaker, 85.3 g of dimethylaminoethyl methacrylate as a precursor of 3-dimethyl (methacryloyloxyethyl) ammonium propane sulfonate as a sulfobetaine group-containing vinyl monomer (A), a hydrophobic group-containing vinyl monomer Weighing 46.9 g of hexyl methacrylate as the body (B), 7.8 g of methoxypolyethylene glycol methacrylate (p = 9) and 77.5 g of ethanol as the vinyl monomer (C) copolymerizable with (A) and (B). And stirred to prepare a homogeneous monomer solution. In addition, 1.6 g of 2,2′-azobis-2-methylbutyronitrile was weighed into a 100 mL beaker and dissolved by adding 25.8 g of ethanol to prepare an initiator solution.
Next, when the internal temperature of the separable flask reached 78 ° C., an initiator solution and a monomer solution were added over 2 hours using a dropping pump, and stirring was further continued for 5 hours to complete the polymerization. . The obtained copolymer solution was diluted with ethanol so that the mass concentration of the copolymer was 15%, and 66.3 g of 1.3-propane sultone was added dropwise over 1 hour at a liquid temperature of 25 ° C. The temperature was raised to 35 ° C., and the reaction was continued for 4 hours. After cooling, the reaction solvent was removed and dried to obtain a copolymer.

Example 1
A copolymer of 3-dimethyl (methacryloyloxyethyl) ammonium propane sulfonate (DMAPS) and hexyl methacrylate (HMA) and methoxypolyethylene glycol methacrylate (p = 9) (M90G) was prepared as a copolymerization ratio (mol%) 65/33 /. 2 and according to Preparation Example 1.
[B] / [A] (mass ratio) of the copolymer was 0.31, and [C] / [A] (mass ratio) was 0.05. In a 300 mL beaker, 7 parts by weight of salt-sensitive polymer and 93 parts by weight of 0.5% NaCl aqueous solution were mixed and dissolved at 40 ° C., and 15 parts by weight of limonene (fragrance) as a core substance of microcapsules was added with stirring. The particle size was adjusted.
Next, 200 parts by weight of purified water was added to the system over 1 hour, so that the salt-sensitive polymer was phase-separated and adsorbed around the core substance. The system temperature was cooled to 25 ° C. to obtain microcapsules using a salt-sensitive polymer as a membrane material. As a result of evaluating the perfume retention effect and perfume release (dissolution or swelling) of this microcapsule, it was good as shown in Table 1 below.

(Example 2)
A copolymer of 3-dimethyl (methacryloyloxyethyl) ammonium propane sulfonate (DMAPS) and hexyl methacrylate (HMA) and methoxypolyethylene glycol methacrylate (p = 9) (M90G) was converted into a copolymerization ratio (mol%) 75/23 /. 2 and according to Preparation Example 1. The copolymer had a [B] / [A] (mass ratio) of 0.19 and a [C] / [A] (mass ratio) of 0.04. In a 300 mL beaker, 5 parts by weight of salt-sensitive polymer and 95 parts by weight of 0.5% NaCl aqueous solution were mixed and dissolved at 40 ° C. with stirring while adding 20 parts by weight of limonene (fragrance) as the core material of the microcapsule The particle size was adjusted. Next, 200 parts by weight of a 0.1% smectite aqueous solution was added to the system over 1 hour, so that the salt-sensitive polymer was phase-separated and adsorbed around the core substance. The system temperature was cooled to 25 ° C. to obtain microcapsules using a salt-sensitive polymer as a membrane material. As a result of evaluating the perfume retention effect and perfume release (dissolution or swelling) of this microcapsule, it was good as shown in Table 1 below.

Example 3
A copolymer of 3-dimethyl (methacryloyloxyethyl) ammonium propane sulfonate (DMAPS) and hexyl methacrylate (HMA) and methoxypolyethylene glycol methacrylate (p = 9) (M90G) and trimethylaminoethyl methacrylate chloride (DMC) was copolymerized. Prepared according to Preparation Example 1 at a ratio (mol%) of 64/33/2/1. [B] / [A] (mass ratio) of the copolymer was 0.31, and [C] / [A] (mass ratio) was 0.06. In a 300 mL beaker, 15 parts by weight of salt-sensitive polymer and 285 parts by weight of 0.5% NaCl aqueous solution were mixed and dissolved at 40 ° C. to prepare an aqueous phase. Using an orifice tube, the aqueous phase serving as a membrane material was placed on the outside, and limonene (fragrance) serving as the core material was placed on the inside, and the liquid was flowed so that the aqueous phase / core material = 50/50. The microcapsule was prepared by adjusting the particle size of the microcapsule by applying vibration to the orifice tube and dropping it into purified water. As a result of evaluating each of the perfume retention property and perfume release property (dissolution or swelling property) of this microcapsule, it was satisfactory as shown in Table 1 below.

Example 4
3-Dimethyl (methacryloyloxyethyl) ammonium propane sulfonate (DMAPS) and 2-ethylhexyl methacrylate (2EHMA) and methoxypolyethylene glycol methacrylate (p = 9) (M90G) and 2-methacrylamide-2-methylpropanesulfonic acid (AMPS) Was prepared according to Production Example 1 at a copolymerization ratio (mol%) of 57/38/2/3. The copolymer had a [B] / [A] (mass ratio) of 0.47 and a [C] / [A] (mass ratio) of 0.10. In a 1.5 L glass container equipped with a scraping paddle and an azimuthal mixer, 50 parts by weight of a salt-sensitive polymer, 795 parts by weight of a 0.2% NaCl aqueous solution, 15 parts by weight of limonene (fragrance), polyoxyethylene hydrogenated castor oil ( 60EO) 0.5 parts by weight was blended and emulsified with homomixer 8000 rpm, paddle 100 rpm, 10 minutes. The obtained emulsion was sprayed into liquid nitrogen to prepare frozen microcapsules and then added to purified water to prepare microcapsules. As a result of evaluating the perfume retention and perfume release (dissolution or swelling) of this microcapsule, it was good as shown in Table 1 below.

(Example 5)
A copolymer of 3-dimethyl (methacryloyloxyethyl) ammonium propane sulfonate (DMAPS) and benzyl methacrylate (BzMA) and methoxypolyethylene glycol methacrylate (p = 9) (M90G) was converted into a copolymerization ratio (mol%) 66/32 / 2 and according to Preparation Example 1. [B] / [A] (mass ratio) of the copolymer was 0.31, and [C] / [A] (mass ratio) was 0.05. In a 300 mL beaker, 5 parts by weight of salt-sensitive polymer and 95 parts by weight of 0.6% NaCl aqueous solution were mixed and dissolved at 40 ° C. with stirring while adding 20 parts by weight of limonene (fragrance) as the core material of the microcapsule. Adjust the particle size. Next, 200 parts by weight of purified water was added to the system over 1 hour, so that the salt-sensitive polymer was phase-separated and adsorbed around the core substance. The system temperature was cooled to 25 ° C. to obtain microcapsules using a salt-sensitive polymer as a membrane material. As a result of evaluating the perfume retention and perfume release (dissolution or swelling) of this microcapsule, it was good as shown in Table 1 below.

(Example 6)
A copolymer of 3-dimethyl (methacryloyloxyethyl) ammonium propane sulfonate (DMAPS) and lauryl methacrylate (LMA) and methoxypolyethylene glycol methacrylate (p = 9) (M90G) was converted into a copolymerization ratio (mol%) 73/25 / 2 and according to Preparation Example 1. [B] / [A] (mass ratio) of the copolymer was 0.31, and [C] / [A] (mass ratio) was 0.05. In a 300 mL beaker, 10 parts by weight of a salt-sensitive polymer and 90 parts by weight of a 2% NaCl aqueous solution were mixed and dissolved at 40 ° C., and 15 parts by weight of limonene (fragrance) as a core material for microcapsules was added with stirring. Adjust. Next, 200 parts by weight of purified water was added to the system over 1 hour, so that the salt-sensitive polymer was phase-separated and adsorbed around the core substance. The system temperature was cooled to 25 ° C. to obtain microcapsules using a salt-sensitive polymer as a membrane material. As a result of evaluating the perfume retention and perfume release (dissolution or swelling) of this microcapsule, it was good as shown in Table 1 below.

(Example 7)
A copolymer of 3-dimethyl (methacryloyloxyethyl) ammonium propane sulfonate (DMAPS) and lauryl methacrylate (LMA) and methoxypolyethylene glycol methacrylate (p = 9) (M90G) was prepared as a copolymerization ratio (mol%) 63/35 / 2 and according to Preparation Example 1. [B] / [A] (mass ratio) of the copolymer was 0.51, and [C] / [A] (mass ratio) was 0.05. In a 300 mL beaker, 7 parts by weight of a salt-sensitive polymer and 93 parts by weight of a 2% NaCl aqueous solution were mixed and dissolved at 40 ° C., and 17 parts by weight of limonene (fragrance) as a core substance for microcapsules was added with stirring. Adjust. Next, 200 parts by weight of a 5% polyvinyl alcohol aqueous solution was added to the system over 1 hour, so that the salt-sensitive polymer was phase-separated and adsorbed around the core substance. The system temperature was cooled to 25 ° C. to obtain microcapsules using a salt-sensitive polymer as a membrane material. As a result of evaluating the perfume retention and perfume release (dissolution or swelling) of this microcapsule, it was good as shown in Table 1 below.

(Example 8)
A copolymer of 3-dimethyl (methacryloyloxyethyl) ammonium propane sulfonate (DMAPS) and lauryl methacrylate (LMA) was prepared according to Preparation Example 1 at a copolymerization ratio (mol%) of 85/15.
[B] / [A] (mass ratio) of the copolymer was 0.16. In a 300 mL beaker, 5 parts by weight of salt-sensitive polymer and 95 parts by weight of 2% NaCl aqueous solution were mixed and dissolved at 40 ° C., and 20 parts by weight of limonene (fragrance) as a core material for microcapsules was added with stirring. Adjusted.
Next, 200 parts by weight of purified water was added to the system over 1 hour, so that the salt-sensitive polymer was phase-separated and adsorbed around the core substance. The system temperature was cooled to 25 ° C. to obtain microcapsules using a salt-sensitive polymer as a membrane material. As a result of evaluating the perfume retention and perfume release (dissolution or swelling) of this microcapsule, it was good as shown in Table 1 below.

Example 9
A copolymer of 3-dimethyl (methacryloyloxyethyl) ammonium propane sulfonate (DMAPS) and lauryl methacrylate (LMA) was prepared according to Preparation Example 1 with a copolymerization ratio (mol%) of 75/25.
[B] / [A] (mass ratio) of the copolymer was 0.30. In a 300 mL beaker, 5 parts by weight of a salt-sensitive polymer and 95 parts by weight of a 6% NaCl aqueous solution were mixed and dissolved at 40 ° C., while adding 15 parts by weight of limonene (fragrance) as a core material of the microcapsule while stirring. Adjusted.
Next, 200 parts by weight of a 0.2% smectite aqueous solution was added to the system over 1 hour, so that the salt-sensitive polymer was phase-separated and adsorbed around the core substance. The system temperature was cooled to 25 ° C. to obtain microcapsules using a salt-sensitive polymer as a membrane material. As a result of evaluating the perfume retention and perfume release (dissolution or swelling) of this microcapsule, it was good as shown in Table 1 below.

(Example 10)
The microcapsules obtained in Example 1 were blended in the lotion having the above composition. In the preparation, it was confirmed that the microcapsule was stable, and the microcapsule was dissolved by perspiration of the human body after application and the perfume was released. Thus, it was found that a skin lotion excellent in stability containing salt-soluble microcapsules can be obtained.

(Example 11)
The microcapsules obtained in Example 2 were blended in a paper diaper having the above composition. It was confirmed that the microcapsules were stable in the preparation, and the microcapsules were dissolved by the human urine after application and the fragrance was released. As a result, it was found that a disposable paper diaper containing salt-soluble microcapsules was obtained.

(Example 12)
The microcapsules obtained in Example 3 were blended with the fragrance described above. It is confirmed that the microcapsules are stable in the formulation, and as the fragrance is used, moisture gradually evaporates, and as the salt concentration in the system increases, the microcapsules dissolve and the fragrance is gradually released. did. Thereby, it turned out that the fragrance | flavor excellent in stability containing the salt-soluble microcapsule is obtained.

(Example 13)
The microcapsules obtained in Example 5 were blended with the softening agent described above. It was confirmed that the microcapsules were stable in the formulation, and the microcapsules were destroyed by wearing clothes treated with a softener, and the perfume was gradually released by sweating. Thereby, it was found that a softener excellent in stability containing salt-soluble microcapsules can be obtained.

(Comparative Example 1)
As a membrane material for microcapsules, 5.0 parts by weight of gelatin (200 to 250 bloom, beef bone alkali treatment) and 1.2 parts by weight of pectin (CP Kelco LM Pectin 102AS) were purified at 68.7 parts by weight at 40 ° C. Dissolved in water. In this aqueous solution, 15.0 parts by weight of limonene (fragrance) that becomes a core substance under stirring was dispersed to adjust the particle diameter of the core substance. Next, 5% aqueous acetic acid solution was added to adjust the pH to 4.3, and then cooled to 20 ° C. to prepare microcapsules. As a result of evaluating the perfume retention and perfume release (dissolution or swelling) of this microcapsule, the perfume retention effect was good as shown in Table 1 below, but the salt concentration was changed (2 to 10). %, The same applies hereinafter), but no fragrance was released.

(Comparative Example 2)
As a microcapsule membrane material, 4.5 parts by weight of agar (Pharmacopoeia agar PS-7) was dispersed in 295.5 parts by weight of purified water and then boiled to prepare an aqueous phase in which the agar was dissolved. The liquid was allowed to flow so that the aqueous phase serving as a membrane material was placed outside the orifice tube, and limonene (fragrance) serving as a core substance was placed inside 90/10. By applying vibration to the orifice tube, the particle size of the microcapsule was adjusted and dropped into an edible oil and fat set in a temperature range where gelation was performed to form a microcapsule. Then, the edible oil and fat adhering to the microcapsule was completely removed to obtain a microcapsule. As a result of evaluating the perfume retention and perfume release properties (dissolution or swelling) of this microcapsule, the perfume retention effect was good as shown in Table 1 below. There was no release.

  As is clear from the results in Table 1 above, Examples 1 to 12 that are within the scope of the present invention are more stable in perfume, functional oil, and the like than Comparative Examples 1 and 2 that are outside the scope of the present invention. In addition, it can be contained in a composition such as cosmetics, hygiene products, fragrances, etc., and further, a microcapsule having excellent properties that can easily dissolve or swell the membrane material and release the core substance by increasing the salt concentration, and It was found that the contained composition was obtained.

Claims (5)

  A microcapsule comprising a salt-soluble polymer as a membrane material.   The microcapsule according to claim 1, wherein the salt-soluble polymer is insoluble in water and dissolves at a salt concentration of 0.01 to 10%.   The microcapsule according to claim 1 or 2, wherein the salt-soluble polymer is a sulfobetaine polymer.   A composition comprising the microcapsule according to any one of claims 1 to 3.   The composition according to claim 4, wherein the composition is any one of a cosmetic composition, a sanitary product composition, a fragrance composition, and a fiber treatment composition.