JP5548391B2 - Hydrogel particles - Google Patents

Description

  The present invention relates to hydrogel particles and a method for producing the same.

  There is known a method for producing hydrogel particles from a dispersion obtained by using a gelling agent that thermally reversibly causes a sol-gel transition and emulsifying and dispersing solid fat and a fragrance with a surfactant.

  For example, in Patent Document 1, an O / W emulsion is prepared by mixing and dispersing an inner oil phase containing dioctyl sebacate and a fragrance with a surfactant such as POE (60) hydrogenated castor oil in an agar solution, A method for producing hydrogel particles is disclosed in which an O / W / O emulsion is prepared by adding it to the outer oil phase and then cooled and solidified. In addition, the same document discloses that there is a polarity difference between the inner oil phase and the outer oil phase so that the fragrance of the inner oil phase in the hydrogel particles does not leak to the outer oil phase. ing.

JP 2001-96146 A

  By the way, when blending hydrogel particles encapsulating perfume into products containing surfactants such as detergents, dentifrices, body soaps, shampoos, the perfume is solubilized outside the particles by the surfactant. There's a problem.

  An object of the present invention is to suppress the perfume contained in the hydrogel particles from being solubilized outside the particles when blended with a product containing a surfactant.

  The present invention is a hydrogel particle having a continuous phase of a hydrogel of an aqueous component and a dispersed phase of an oily component dispersed in the continuous phase, wherein the aqueous component is a component (A): a thermoreversibly sol- Gelling agent that causes gel transition, (B) component: surfactant, and (C) component: water and the oil component is (D) component: hydrocarbon having a melting point of 40 ° C. or higher, and (E) component : Including the fragrance, the content ratio of the component (D) in the oil component to the component (E) (content of component (D) / content of component (E)) is 1/20 to 7.5 / 20.

The present invention includes (A) component: a gelling agent that causes thermo-reversible sol-gel transition, (B) component: a surfactant, and (C) component: an aqueous component solution containing water, and (D) component. : Hydrocarbon having a melting point of 40 ° C. or higher, and (E) component: an oily component containing a fragrance so that the content mass ratio of the (D) component to the (E) component is 1/20 to 7.5 / 20 It is the manufacturing method of the hydrogel particle which has a stirring process process which stir-processes the mixture with a solution with the stirring energy of 200-5000 kWxmin / m < ³ >, and prepares a dispersion liquid.

  According to the present invention, the content mass ratio of the predetermined hydrocarbon as the component (D) to the fragrance as the component (E) is 1/20 to 7.5 / 20, so it is blended into a product containing a surfactant. Even when it does, it can suppress that the fragrance | flavor included in the hydrogel particle is solubilized outside the particle.

  Hereinafter, embodiments will be described in detail.

(Hydrogel particles)
The hydrogel particles according to this embodiment have a continuous phase of an aqueous component and a dispersed phase of an oily component.

  Here, the “hydrogel particles” in the present application are one or a plurality of particles in which a dispersed phase of an oily component is dispersed in a continuous phase of a hydrogel of an aqueous component, and are a core component that is an inner layer and an outer layer. This does not include capsules with a concentric outer skin. The “hydrogel” in the present application refers to a gel obtained from a gelling agent using water as a solvent. The structure in which the dispersed phase is dispersed in the continuous phase in the hydrogel particles can be confirmed by, for example, observation analysis of SEM photographs.

  Although the shape of the hydrogel particle which concerns on this embodiment is not specifically limited, It is preferable that it is the shape of the rotary body comprised by the curved surface. Here, the “rotary body constituted by a curved surface” means a closed figure constituted by a virtual axis and a continuous curve, rotated by the virtual axis, and has a shape such as a triangular pyramid or a cylinder. Is not included. The shape of the hydrogel particles is more preferably spherical or elliptical from the viewpoint of aesthetics.

  The average particle size of the hydrogel particles according to the present embodiment is preferably 5 to 10,000 μm, more preferably 30 to 3000 μm, further preferably 50 to 1000 μm, and further preferably 60 to 500 μm. More preferred. The average particle size of the hydrogel particles can be measured by a laser diffraction / scattering method using a laser diffraction / scattering particle size distribution measuring device (for example, model number: LA-910, manufactured by Horiba, Ltd.).

  In the hydrogel particles according to this embodiment, the content ratio of the dispersed phase of the oil component to the continuous phase of the aqueous component is preferably aqueous component / oil component = 40/60 to 95/5, and 60/40 to 90. More preferably, it is / 10.

  The average particle size of the dispersed phase of the oil component is preferably 0.01 to 20 μm, more preferably 0.02 to 15 μm, still more preferably 0.03 to 10 μm, and 0.03 to 3 μm. Even more preferably. The average particle size of the oil component is determined by laser diffraction using a laser diffraction / scattering particle size distribution measuring device (for example, model number: LA-910, manufactured by HORIBA, Ltd.) for the dispersion before forming the hydrogel particles. It can be measured by the scattering method.

  In the hydrogel particles according to this embodiment, the aqueous component constituting the continuous phase contains (A) component: gelling agent, (B) component: surfactant, and (C) component: water.

<(A) component: gelling agent>
The gelling agent as component (A) is one that causes a sol-gel transition in a thermoreversible manner. Therefore, the hydrogel particles according to the present embodiment are non-crosslinked hydrogel particles. Here, the “non-crosslinked hydrogel” means that gelation does not occur when the gelling agent reacts with ions such as potassium ions and calcium ions and crosslinks, but the gelling agent is agar. In this way, it is caused by the thermoreversibility of sol-gel.

  Examples of the component (A) include agar, gelatin, gellan gum and the like. The gelling agent may be composed of a single species or a plurality of species.

  The content of the component (A) in the hydrogel particles is preferably 0.1 to 8% by mass from the viewpoint of preventing breakage of the hydrogel particles when blended with cosmetics and dentifrices, More preferably, it is -5 mass%.

The component (A) is preferably agar. Agar generally has a melting temperature in water of 75 ° C. or higher, and the main one is 75 to 90 ° C. On the other hand, the gel temperature when dissolved in water and then cooled is 30 to 45 ° C. . Agar, from the viewpoint of feel during use, it is preferred that the jelly strength is less 68.6kPa (700g / cm ^2), more to be 19.6~63.7kPa (200~650g / cm ²⁾ preferable. Here, the jelly strength is determined by the Nissho water method. Specifically, according to the Nissho water method, the jelly strength is obtained by preparing a 1.5% by mass aqueous solution of a gelling agent and allowing the aqueous solution to stand at 20 ° C. for 15 hours to solidify the gel. It is the maximum mass (g) per surface area of 1 cm ² when a load is applied by an expression jelly strength measuring instrument (manufactured by Kiyama Seisakusho Co., Ltd.) and the gel withstands the load for 20 seconds at 20 ° C.

<(B) component>
As the surfactant which is component (B), for example, non-ionic surfactants include polyglycerin fatty acid ester, sucrose fatty acid ester, polyoxyethylene alkyl ether, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene tetraoleate Examples include sorbitol, polyoxyethylene hydrogenated castor oil, and anionic surfactants such as alkyl sulfate, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl acetate, polyoxyethylene alkyl ether phosphate, fatty acid. Salts, N-acyl taurine salts, N-acyl amino acid salts and the like, and cationic surfactants include alkylamine acetate, alkyltrimethylammonium chloride, dialkyldimethylammonium chloride, and alkyl Examples of amphoteric surfactants include alkyldimethylaminoacetic acid betaine, alkyldimethylamine oxide, alkylcarboxymethylhydroxyethylimidazolinium betaine, alkylamidopropyl betaine, and enzymolytic lecithin. . The component (B) is preferably an anionic surfactant, more preferably an N-acyl taurine salt, particularly N-stearoylmethyl, from the viewpoint of emulsion stability of the oil component and suppression of gel strength reduction. More preferred is sodium taurine. (B) A component may be comprised by single type and may be comprised by multiple types.

  The content of the component (B) in the hydrogel particles is preferably 0.01 to 10% by mass, more preferably 0.1 to 5% by mass, and 0.15 to 3% by mass. More preferably. From the viewpoint of maintaining stability in the dispersion of the component (B) and the component (D), the content is preferably 0.01% by mass or more, and from the viewpoint of avoiding a reduction in gel strength of the agar, the content is It is preferable that it is 10 mass% or less.

<(C) component>
The content of the water (C) in the hydrogel particles is preferably 40 to 95% by mass, and more preferably 60 to 90% by mass.

  In the hydrogel particles according to the present embodiment, the oil component constituting the dispersed phase includes (D) component: hydrocarbon and (E) component: perfume.

<(D) component>
The hydrocarbon as component (D) has a melting point of 40 ° C. or higher, preferably 50 ° C. or higher, and preferably 95 ° C. or lower from the viewpoint of melting during production, 85 ° C. The following are more preferable.

  Examples of the component (D) include paraffin wax, microcrystalline wax, ceresin, soft wax, and Japanese pharmacopoeia paraffin described in JISK2235. (D) A component may be comprised by single type and may be comprised by multiple types.

  The content of the component (D) in the hydrogel particles is preferably 0.1% by mass or more, and more preferably 1% by mass or more. Further, from the viewpoint of suppressing the thickening of the dispersion, it is preferably 20% by mass or less, and more preferably 10% by mass or less.

<(E) component>
(E) As a fragrance | flavor which is a component, in addition to synthetic fragrances, such as menthol, carvone, anethole, eugenol, cineol, thymol, methyl salicylate, pregon, menthone, pinene, limonene, menthyl acetate, peppermint oil, spearmint oil, mint oil Citrus oils such as lemon, orange, grapefruit, lime; herbal oils such as eucalyptus, sage, rosemary, thyme, laurel, basil, perilla, bay, estragon, parsley, celery, coriander; cinnamon, pepper, Natural essential oils such as nutmeg, mace, clove, ginger, cardamom, anise and other spice oil, apple, banana, melon, grape, peach, strawberry, blueberry, raspberry, blackcurrant, lychee, star fruit, Tsu Deployment fruit, plum, pineapple, fruit flavors, etc., such as Muscat and the like. The component (E) is preferably an oil-soluble fragrance such as menthol, carvone, peppermint oil, spearmint oil, mint oil, cineol, orange oil, and pinene. (E) A component may be comprised by single type and may be comprised by multiple types.

  The content of the component (E) in the hydrogel particles is preferably 1% by mass or more, and more preferably 5% by mass or more. Further, from the viewpoint of suppressing the increase in viscosity of the dispersion, it is preferably 50% by mass or less, and more preferably 35% by mass or less.

  In the hydrogel particles according to the present embodiment, the content mass ratio of the (D) component to the (E) component (the content mass of the (D) component / the content mass of the (E) component) is 1/20 to 7.5 / 20. It is. The content mass of the component (D) / the content mass of the component (E) is preferably 1/20 to 7.5 / 20 from the viewpoint of suppressing outflow (solubilization) from the hydrogel particles during storage. The ratio is more preferably 1.5 / 20 to 7/20, further preferably 2/20 to 6.5 / 20, and still more preferably 2/20 to 6/20. By making the mass ratio of the component (D) / component (E) higher than 1/20, the fragrance can be retained in the crystal of the hydrocarbon component of an appropriate size, and the fragrance flows out from the hydrogel particles. (Solubilization) can be suppressed. Moreover, it can suppress that a fragrance | flavor flows out (solubilization) from a hydrogel particle for the same reason as the above by making mass ratio of (D) component / (E) component lower than 7.5 / 20. it can.

  The hydrogel particles according to this embodiment may further contain solid particles that are the component (F). The component (F) may be included in the continuous phase, may be included in the dispersed phase, and may be included in both of them.

  As the solid particles as component (F), for example, a hydrogel particle colorant, a feel improver that improves the dry feeling when cosmetics containing hydrogel particles are used on the skin, and hydrogel particles are blended. Examples thereof include a polishing improver that improves the polishing action when a dentifrice is used for toothpaste. Examples of the component (F) pigment include carbon black, talc, kaolin, mica, mica titanium, iron oxide (bengal), yellow iron oxide, black iron oxide, bismuth oxychloride, magnesium silicate, titanium oxide, and calcium carbonate. Inorganic pigments: red 202, red 204, red 205, red 206, red 219, red 228, red 404, yellow 205, yellow 401, orange 401, blue 404, etc. An organic pigment is mentioned. Examples of the cosmetic powder of component (F) include talc, kaolin, sericite, calcium carbonate, magnesium carbonate, magnesium silicate, calcium silicate, anhydrous silicic acid, titanium oxide, zinc oxide, titanium mica, silica, and zeolite. , Barium sulfate, calcium phosphate, hydroxyapatite, metal soap, polyethylene powder, polystyrene powder and the like. Examples of the natural polymer powder of component (F) include cellulose powder, chitosan powder, starch powder, silk powder, and crystalline cellulose powder. Component (F) may be composed of a single species or a plurality of species.

  Component (F) is preferably water-insoluble. Here, “water-insoluble” means that dissolution in water at 25 ° C. is 0.1% by mass or less. Moreover, it is preferable that the particle size of (F) component is 0.05-50 micrometers. Furthermore, it is preferable that the specific gravity with respect to the water of (F) component is 1.1-8.0. Among these, calcium carbonate is more preferable from the viewpoint of foam suppression.

  The content of the component (F) in the hydrogel particles is preferably 0.1 to 30% by mass, and more preferably 0.5 to 10% by mass.

  In addition to the above components, the hydrogel particles according to the present embodiment include, for example, saccharides, polyhydric alcohols, preservatives, water-soluble colorants, antioxidants, etc. May be included.

  The hydrogel particles according to the present embodiment having the above-described configuration are blended in a product containing a surfactant such as a detergent, a dentifrice, a body soap, a shampoo, etc., but (D) a predetermined hydrocarbon as a component. (E) Since the mass ratio with respect to the fragrance, which is the component, is 1/20 to 7.5 / 20, the fragrance contained in the hydrogel particles can be added to the outside of the particle even when blended with products containing a surfactant. It can suppress solubilization.

(Method for producing hydrogel particles)
Next, the manufacturing method of the hydrogel particle which concerns on this embodiment is demonstrated.

  In the method for producing hydrogel particles according to the present embodiment, first, (A) component: a gelling agent that causes a sol-gel transition thermoreversibly, (B) component: surfactant, and (C) component: water. And (D) component: hydrocarbon having a melting point of 40 ° C. or higher, and (E) component: perfume, the content ratio of (D) component to (E) component is 1/20 to 7.5. After preparing each oil component solution to be / 20, a mixture thereof is prepared (mixture preparation step).

  Next, the mixture prepared in the mixture preparation step is stirred to prepare a dispersion (stirring step).

  At this time, the stirring device used in the stirring process is not particularly limited, and a known device can be applied. Examples of such a stirring device include a homomixer, a line mixer, and a disper that can exhibit a high shearing force. Among these, it is more preferable to use a homomixer from the viewpoint of operability.

And in the manufacturing method of the hydrogel particle which concerns on this embodiment, when stirring a mixture, the stirring energy of 200-5000 kWxmin / m < ³ > is given with respect to a mixture. The stirring energy is preferably in a 230～4500KW × min / ^{m 3,} and more preferably to 250～4200KW × min / ^{m 3.} From the viewpoint of suppressing sedimentation of particles in the dispersion and preventing leakage of oily components when the hydrogel particles are blended in an aqueous medium, the stirring energy is 200 kW × min / m ³ or more. Preferably, the stirring energy is preferably 5000 kW × min / m ³ or less from the viewpoint of maintaining the stability of the dispersion to suppress the increase in viscosity and avoiding a prolonged production time.

Here, in this application, “stirring energy” is obtained by stirring power P / V (kW / m ³ ) × time (minutes), and a detailed calculation formula is disclosed in Japanese Patent Application Laid-Open No. 2007-161683. Have been described. For example, the calculation formula of the stirring energy when using a homomixer is as shown by the following formula (I).

Stirring energy (kW x min / m ³ )
= [Stirring power P (kW)] / [Treatment liquid volume V (m ³ )] × Stirring time (min) (I)
In the above formula (I), the stirring power P (kW) is calculated by the following experimental formula 1.

Stirring power P (kW) = Np × n ³ × d ⁵ × ρ / 1000 (empirical formula 1)
Np: Number of powers (in the case of a homomixer, Np = 1.5 for a homomixer with a stirring tank capacity of less than 10 L, and Np = 1.3 for a homomixer with a stirring tank capacity of 10 L or more)
n: Stirring rotation speed (-/ sec)
d: Diameter of stirring blade (m)
ρ: Density (kg / m ³ ) of contents (mixture).

  The temperature of the mixture or dispersion during the stirring treatment is preferably 60 to 90 ° C. The pH of the mixture or dispersion during the stirring treatment is preferably 5.5 to 8.5 (80 ° C.).

  Subsequently, the dispersion liquid prepared in the stirring treatment step is formed into droplets by a general dropping method, spraying method, or stirring method, and then the droplets are cooled and solidified to form hydrogel particles (particle forming step). ).

  The dropping method uses the property that a dispersion liquid is discharged from a hole and the discharged dispersion liquid becomes a droplet by its surface tension or interfacial tension, and the droplet is cooled in a gas phase such as air or in a liquid phase. It is a method of solidifying to form hydrogel particles. In addition, from the viewpoint of forming hydrogel particles having a uniform particle size, it is preferable to vibrate the dispersion discharged from the holes.

  The spraying method uses a spray nozzle to discharge (spray) the dispersion liquid into the gas phase from the spray nozzle and form droplets by the surface tension, and cool and solidify the droplets in the gas phase to form hydrogel particles. It is a method of forming. When using the spraying method, the aqueous component and the oily component may be continuously supplied to the continuous emulsifier to obtain a dispersion, which may be sprayed from a spray nozzle directly connected to the continuous emulsifier. In this way, since the retention time as the dispersion is almost eliminated, the dispersion is not required to have emulsion stability. Therefore, even if it is an active ingredient that lowers the emulsion stability, the blending amount is large. can do.

  In the stirring method, the dispersion is poured into a liquid that has a property that does not substantially mix with the dispersion and is adjusted to a temperature equal to or higher than the gelling temperature, and the dispersion is atomized by a shearing force by stirring. This is a method of forming hydrogel particles by utilizing the property of forming droplets and cooling and solidifying the droplets in a liquid that does not substantially mix with the dispersion.

  In any of the dropping method, the spraying method, and the stirring method, it is preferable that the temperature of the dispersion liquid at the time of discharging, spraying, or charging is a temperature not lower than the gelling temperature and not higher than 100 ° C. Further, from the viewpoint that spherical particles having excellent aesthetics can be easily produced, the temperature of the dispersion is preferably set to a gelling temperature + 10 ° C. or higher, and to a gelling temperature + 20 ° C. or higher. More preferred. The upper limit of this temperature is 100 ° C., which is the boiling point of water. Specifically, the temperature of the dispersion is preferably 60 to 90 ° C, and more preferably 70 to 80 ° C.

  The hydrogel particles obtained as described above have the same configuration as the dispersion, and therefore, the content ratio of each component in the dispersion liquid becomes the content ratio of that component in the hydrogel particles as it is. Moreover, about the obtained hydrogel particle, you may further refine | miniaturize by grinding | pulverization etc. as needed.

(Preparation of dispersion and production of hydrogel particles)
The following dispersions of Examples 1 to 3 and Comparative Examples 1 to 3 were prepared and hydrogel particles were prepared. Tables 1 and 2 also show the respective configurations.

<Example 1>
(A) component agar (trade name: AX-200 manufactured by Ina Food Industry Co., Ltd.), (B) component N-stearoylmethyl taurine sodium (trade name: SMT manufactured by Nikko Chemicals), and (F) component A certain amount of calcium carbonate (trade name: Toyo White, manufactured by Toyo Denka Kogyo Co., Ltd.) is added to ion-exchanged water, which is a component (C) at room temperature, and heated and mixed at 90 ° C. for 30 minutes, then cooled to 80 ° C. and an aqueous solution. A (aqueous component) was prepared.

  Further, ceresin (product name: ceresin 810K (melting point: 74.1 ° C.) manufactured by Nikko Rica Co., Ltd.) as component (D), and I-menthol (product name menthol crystal manufactured by Takasago Inc.) as component (E) and Essential oil (trade name: Orange oil manufactured by Ogawa Fragrance Co., Ltd.) was heated and mixed at 80 ° C. to adjust the oil component. The melting point of (D) ceresin is an endothermic peak temperature when DSC (Differential Scanning Calorimeter: Rigaku Corporation, Thermo plus DSC8230) is used and the rate of temperature rise of the sample is 2 ° C./min ( The same applies to the following (D) microcrystalline wax and behenyl alcohol).

  The total amount of each component is (A) agar 3.00% by mass, (B) stearoylmethyl taurine Na 0.38% by mass, (F) calcium carbonate 4.00% by mass, (D) ceresin 2 .50% by mass, (E) 1-0.00% by mass of I-menthol and 10.00% by mass of essential oil, and (C) ion-exchanged water was set as the balance. Therefore, the content mass of the component (D) / the content mass of the component (E) is 2.5 / 20.

An oil component is added to the aqueous solution A to obtain 800 g of a mixture, and the mixture is homomixer (trade name: TK Robotics, manufactured by Primics Co., Ltd., power Np = 1.5, stirring blade diameter d = 0.025 m). And a stirring blade was rotated at a stirring speed n = 250 times / sec for a stirring time t = 1.5 minutes to prepare a dispersion. Content density of (mixtures) ρ = 950kg / ^{m 3,} and the treatment liquid has a volume V = 0.00084m ^3. Therefore, the stirring power P = 0.217 kW, and the stirring energy is 387 kW / m ³ · min.

  The obtained dispersion liquid is sprayed into cooling air at a flow rate of 30 L / hr and a spraying pressure of 1.1 to 1.3 MPa using a one-fluid nozzle having a pore diameter of 0.9 mm, whereby droplets of the dispersion liquid are sprayed. Produced hydrogel particles which were cooled and solidified.

<Example 2>
(D) A dispersion was prepared and hydrogel particles were prepared in the same manner as in Example 1 except that the blending amount of ceresin was 5.00% by mass. (D) Component mass / (E) component mass is 5/20.

<Comparative Example 1>
(D) A dispersion was prepared in the same manner as in Example 1 except that ceresin was not blended, and hydrogel particles were prepared. The content mass of the component (D) / the content mass of the component (E) is 0/20.

<Comparative example 2>
(D) A dispersion was prepared and hydrogel particles were prepared in the same manner as in Example 1 except that the blending amount of ceresin was 10.00% by mass. (D) Component mass / (E) component mass is 10/20.

<Example 3>
(D) Instead of ceresin, (D) microcrystalline wax (trade name: Multiwax W-835 (melting point: 77.8 ° C.) manufactured by Sonneborn) was added so that the total content was 5.00% by mass. Except for blending, a dispersion was prepared in the same manner as in Example 1, and hydrogel particles were produced. (D) Component mass / (E) component mass is 5/20.

<Comparative Example 3>
(D) Except that behenyl alcohol (trade name: Calcoal 220-80 (melting point: 72.0 ° C)) manufactured by Kao Corporation was blended in place of ceresin so that the total content was 5.00% by mass. A dispersion was prepared in the same manner as in Example 1, and hydrogel particles were produced.

(Test evaluation method)
<Average particle size of oil component in dispersion>
About the dispersion liquid prepared in each of Examples 1 to 3 and Comparative Examples 1 to 3, the median diameter was measured using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.). Was the average particle size of the oil component in the dispersion. The average particle size of the oil component is approximately equal to the average particle size of the oil component in the hydrogel particles.

<Average particle size of hydrogel particles>
For the hydrogel particles produced in each of Examples 1 to 3 and Comparative Examples 1 to 3, the median diameter was measured using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.) This was defined as the average particle size of the hydrogel particles.

<Perfume extraction rate>
3 g of the hydrogel particles produced in each of Examples 1 to 3 and Comparative Examples 1 to 3 were sampled and dispersed in 27 g of a sodium alkylsulfate aqueous solution having a concentration of 1% by mass, and then transferred to a screw tube. The solution was stored at 24 ° C. for 24 hours. Then, after separating hydrogel particles and sodium alkyl sulfate aqueous solution with a syringe filter, 10 g of the aqueous solution was weighed, 0.5 g of calcium chloride was added and stirred with a stirrer for 10 minutes, 10 mL of diethyl ether and 1% of internal standard substance 1 mL of an ethanol solution was added and stirred with a stirrer for 10 minutes, and the ether layer was analyzed by gas chromatography to measure the amount of limonene that was the main component of orange oil solubilized on the aqueous solution side.

(Test evaluation results)
Table 1 shows the test results.

  The average particle size of the oil component in the dispersion is 0.49 μm in Example 1, 0.55 μm in Example 2, while 0.45 μm in Comparative Example 1, 0.80 μm in Comparative Example 2, and Example 3 Was 0.59 μm and Comparative Example 3 was 0.79 μm.

  The average particle size of the hydrogel particles was 140 μm in Example 1 and 130 μm in Example 2, while 132 μm in Comparative Example 1, 135 μm in Comparative Example 2, 142 μm in Example 3 and 138 μm in Comparative Example 3 .

  (E) Extraction rate of essential oil (orange oil) is 6.19% in Example 1 and 6.02% in Example 2, while 7.87% in Comparative Example 1 and 10.22% in Comparative Example 2. In addition, Example 3 was 5.96% and Comparative Example 3 was 8.33%.

  The present invention is useful for hydrogel particles and methods for producing the same.

Claims (10)

Hydrogel particles having a continuous phase of a hydrogel of an aqueous component and a dispersed phase of an oily component dispersed in the continuous phase,
The aqueous component contains (A) component: a gelling agent that causes thermo-reversible sol-gel transition, (B) component: surfactant, and (C) component: water, and the oily component is (D) Ingredient: at least one of ceresin and microcrystalline wax which are hydrocarbons having a melting point of 40 ° C. or higher, and (E) ingredient: containing oil-soluble fragrance,
The hydrogel particle whose content mass ratio with respect to the said (E) component of the said (D) component in the said oil-based component is 1 / 20-7.5 / 20.   (F) Component: The hydrogel particle of Claim 1 which further contains a solid particle. The oil-soluble fragrance of the component (E) is at least one selected from the group consisting of menthol, carvone, peppermint oil, spearmint oil, mint oil, cineol, orange oil, and pinene. The hydrogel particles described.   The hydrogel according to any one of claims 1 to 3, wherein the component (A) is agar and the content of the agar as the component (A) is 0.1 to 8.0% by mass. particle.   The component (B) is an anionic surfactant, and the content of the anionic surfactant as the component (B) is 0.01 to 10% by mass. The hydrogel particle according to Item. The hydrogel particle according to claim 5, wherein the anionic surfactant as the component (B) is an N-acyl taurine salt.   The hydrogel particle according to any one of claims 1 to 6, wherein an average particle diameter of the oil component is 0.01 to 20 µm. (A) Component: Gelling agent that causes thermo-reversible sol-gel transition, (B) Component: Surfactant, and (C) Component: An aqueous component solution containing water, and (D) Component: melting point 40 ° C. At least one of the above-mentioned hydrocarbons , ceresin and microcrystalline wax , and the component (E): oil-soluble fragrance, the content ratio of the component (D) to the component (E) is 1 / 20-7. 5/20 and oil component solution comprises as a, a mixture of, having a stirring process of preparing the stirring process to the dispersion at a stirring energy of 200～5000KW × min / m ^3, the production method of the hydrogel particles .   The hydrogel particles according to claim 8, further comprising a particle forming step of cooling and solidifying the liquid droplets after discharging the dispersion obtained in the stirring treatment step from a spray nozzle to form liquid droplets. Production method.   Hydrogel particles obtained by the production method according to claim 8 or 9.