JP6689517B2 - Oily dispersion, emulsified composition using this oily dispersion, and cosmetics using this emulsified composition - Google Patents

Description

The present invention relates to an oily dispersion containing zinc oxide or titanium oxide having an ultraviolet shielding ability, and ethylhexyl methoxycinnamate (Octyl 4-methoxycinnamate, hereinafter also referred to as OMC) having an ultraviolet absorbing ability, and this oily dispersion. The present invention relates to an emulsified composition. More specifically, an oily dispersion capable of dispersing zinc oxide or titanium oxide and OMC, which are conventionally agglomerated when mixed, in the system without causing an agglomeration phenomenon, and an emulsion composition using the oily dispersion. It is about.
The present invention also relates to cosmetics using this emulsified composition.

  It has been known that zinc oxide or titanium oxide has an ultraviolet ray shielding ability and OMC has an ultraviolet ray absorbing ability.

However, when zinc oxide or titanium oxide and OMC are used together, an agglomeration phenomenon occurs, so it is difficult to form a uniform dispersed state of zinc oxide or titanium oxide and OMC, and There was a problem that it was difficult to maintain.
Therefore, in the past, when zinc oxide or titanium oxide was used in combination with OMC, the ultraviolet ray shielding ability of zinc oxide or titanium oxide and the ultraviolet ray absorbing ability of OMC could not be sufficiently and stably exhibited. is there.

  As a composition in which zinc oxide and OMC are used in combination, for example, Patent Document 1 discloses a UV-shielding cosmetic containing zinc oxide and OMC.

JP, 2006-335654, A

  However, such a cosmetic is intended to improve the unpleasant odor of OMC, as described in Patent Document 1 [0007], and agglomerates zinc oxide or titanium oxide with OMC. It is not intended to be used (dispersed) without the use. It should be noted that Patent Document 1 discloses the evaluation result for odor, but does not disclose any dispersion state.

Recently, the inventors of the present invention have conducted extensive studies, and as a result, by using a polyhydroxy fatty acid, an oily dispersion that can disperse zinc oxide or titanium oxide and OMC in the system without causing an aggregation phenomenon is obtained. We have come to the knowledge that it can be obtained.
Further, an emulsion composition or a cosmetic prepared by using such an oily dispersion may exhibit an ultraviolet shielding ability and an ultraviolet absorbing ability which are extremely higher than those of a conventional emulsion composition or a cosmetic using OMC. all right.

The present invention has been made in view of the conventional problems described above, and disperses zinc oxide or titanium oxide and OMC that would otherwise cause aggregation in the system without causing the aggregation phenomenon. The object is to provide an oily dispersion that can be used and an emulsion composition using this oily dispersion.
Moreover, it aims at provision of the cosmetics using this emulsified composition.

In order to achieve the above object, the oily dispersion according to claim 1 of the present invention is zinc oxide or titanium oxide having an average primary particle diameter of 1 to 50 nm, which is surface-treated with isostearic acid or a metal salt of isostearic acid, It is characterized by containing ethylhexyl methoxycinnamate and polyhydroxy fatty acid (excluding a surfactant selected from alkylmethyl taurine salt and / or phospholipid).

  The oily dispersion according to claim 2 of the present invention is characterized in that the content of the polyhydroxy fatty acid is 0.05 to 20% by weight based on the total weight of the oily dispersion.

  The oily dispersion according to claim 3 of the present invention is characterized in that the content of ethylhexyl methoxycinnamate is 30 to 80% by weight based on the total weight of the oily dispersion.

The oil dispersion according to claim 4 of the present invention is characterized in that the polyhydroxy fatty acid is polyhydroxystearic acid .

  An emulsified composition according to claim 5 of the present invention is characterized by containing the oily dispersion according to any one of claims 1 to 4.

  The emulsion composition according to claim 6 of the present invention is characterized by further containing an emulsifier.

  The emulsified composition according to claim 7 of the present invention is characterized by further containing a cyclic siloxane or a hydrocarbon oil.

  The emulsion composition according to claim 8 of the present invention is characterized in that all of 10% cumulative particle diameter (D10), 50% cumulative particle diameter (D50) and 90% cumulative particle diameter (D90) are 1 μm or less. And

  The emulsion composition according to claim 9 of the present invention is characterized in that the light transmittance at 330 to 370 nm is 20% or less.

  A cosmetic according to claim 10 of the present invention is characterized in that the oily dispersion according to any one of claims 1 to 4 is blended.

  A cosmetic material according to claim 11 of the present invention is characterized by containing the emulsion composition according to any one of claims 5 to 9.

  According to the oily dispersion of the present invention, by containing zinc oxide or titanium oxide, ethylhexyl methoxycinnamate, and polyhydroxy fatty acid, ethylhexyl methoxycinnamate can be obtained without aggregating zinc oxide or titanium oxide. Can be mixed with.

  According to the oily dispersions according to claims 2 and 3 of the present invention, the above effects can be more remarkably exhibited by setting the content of ethylhexyl methoxycinnamate or polyhydroxy fatty acid within a specific range. .

  According to the oily dispersion of the fourth aspect of the present invention, the above effect can be more remarkably exhibited by using a specific compound for the polyhydroxy fatty acid.

  According to the emulsified composition according to claims 5 to 9 of the present invention, by emulsifying the oily dispersion according to the present invention, zinc oxide or titanium oxide and methoxysilica which are uniformly dispersed in the oily dispersion without agglomeration. The dispersed state of ethylhexyl cinnamate can be stably maintained even in an emulsified state such as O / W type or W / O type.

  In particular, according to the oily dispersion of claim 7 of the present invention, by containing a cyclic siloxane or a hydrocarbon oil as a dispersion medium, further zinc oxide or titanium oxide and ethylhexyl methoxycinnamate are not aggregated. It is possible to obtain an oily dispersion that can be uniformly dispersed and can stabilize its dispersed state.

  According to the cosmetics of claims 10 and 11 of the present invention, by using the oil dispersion according to the present invention or the emulsified composition according to the present invention, the ultraviolet ray shielding ability of zinc oxide or titanium oxide and the methoxy caustic skin are provided. It is possible to obtain a cosmetic that can sufficiently exhibit both performances without impairing the ultraviolet absorption performance of ethylhexyl acid.

3 is a graph showing the transmittance curves of the oil dispersions of Example 1 and Comparative Example 1. 5 is a graph showing the transmittance curves of the oil dispersions of Example 2 and Comparative Example 2. Immediately after the preparation of the emulsion composition of Example 3 (using the oily dispersion of Example 1), the emulsion composition of Comparative Example 3 (using the oily dispersion of Comparative Example 1), and the emulsion composition of Comparative Example 4 It is a micrograph. 7 days after preparation of the emulsion composition of Example 3 (using the oily dispersion of Example 1), the emulsion composition of Comparative Example 3 (using the oily dispersion of Comparative Example 1), and the emulsion composition of Comparative Example 4 It is an optical microscope photograph at the time. The transmittance curves of the emulsion composition of Example 3 (using the oily dispersion of Example 1), the emulsion composition of Comparative Example 3 (using the oily dispersion of Comparative Example 1), and the emulsion composition of Comparative Example 4 are shown. It is a graph shown.

  An embodiment of the present invention will be described with reference to the drawings. The embodiments described below are merely examples embodying the present invention and do not limit the technical scope of the present invention.

(Basic structure)
The oily dispersion according to the present invention has a basic structure containing zinc oxide or titanium oxide, ethylhexyl methoxycinnamate (OMC), and polyhydroxy fatty acid.
Thus, by using polyhydroxy fatty acid as an essential component, it is possible to disperse zinc oxide or titanium oxide and OMC, which would otherwise cause an aggregation phenomenon, in the system without causing the aggregation phenomenon. is there.

  Hereinafter, each component of the present invention will be described.

(Zinc oxide or titanium oxide)
Zinc oxide or titanium oxide used in the present invention is not particularly limited in terms of other physical properties as long as it has an ultraviolet shielding ability, but in order to sufficiently exhibit its properties, the average primary particle diameter is 1 to 1 It is preferable to use one having a range of 100 nm. In addition, it is preferable to use one having a range of 5 to 70 nm, and further preferable to use one having a range of 5 to 50 nm.

  The zinc oxide or titanium oxide used in the present invention may have the surface treated with various compounds. Examples of such a compound include isostearic acid or a metal salt of isostearic acid.

Furthermore, when surface treatment is performed using isostearic acid or a metal salt of isostearic acid, in order to improve the light resistance of zinc oxide or titanium oxide and suppress the reactivity with other substances, an inorganic oxide such as aluminum is previously prepared. Alternatively, a coating treatment of zinc oxide or titanium oxide can be performed with a hydroxide.
As a coating treatment method, for example, zinc oxide or titanium oxide is dispersed in an aqueous system, a water-soluble salt of an inorganic oxide or hydroxide such as aluminum to be coated is dissolved therein, and the powder surface is adjusted while adjusting the pH. Examples thereof include a method of coating zinc oxide or titanium oxide by depositing a coating material such as aluminum hydroxide on the above. At this time, isostearic acid or a metal salt of isostearic acid is mixed with a water-soluble salt of an inorganic oxide or hydroxide such as aluminum to be coated, at the same time as water in which zinc oxide or titanium oxide as a base material is dispersed. Alternatively, a water-soluble salt of an inorganic oxide such as aluminum or a hydroxide, which is previously coated, may be dissolved to perform coating treatment, and then mixed.

  In addition, when a metal salt containing isostearic acid as a main constituent such as aluminum isostearate is used, the same effect as the above-mentioned coating treatment can be obtained in the surface treatment without performing the treatment.

  Here, the ratio of the inorganic oxide or hydroxide as the coating substance to zinc oxide or titanium oxide in the above coating treatment is preferably 1 to 25% by weight, and more preferably 2 to 15% by weight in terms of oxide. If it is less than 1%, improvement of light resistance or suppression of reactivity cannot be sufficiently exerted, and if it exceeds 25%, the ratio of zinc oxide or titanium oxide in the oily dispersion is reduced and the ultraviolet ray shielding ability is deteriorated. Is caused, and the effect of the coating treatment reaches the ceiling.

  The content of zinc oxide or titanium oxide in the oily dispersion will be appropriately determined according to the desired ultraviolet light shielding effect, but from the viewpoint of the viscosity, transparency, usability of the oily dispersion, etc. It is preferably 20 to 80% by weight based on the total weight of the dispersion, and more preferably 30 to 70% by weight based on the total weight of the oily dispersion.

(Ethylhexyl methoxycinnamate)
The ethylhexyl methoxycinnamate (OMC) used in the present invention has an ultraviolet absorbing ability, and is a compound having excellent ultraviolet absorbing ability particularly in the UVB wavelength range (about 280 to 320 nm) among ultraviolet rays.
The content of OMC in the oily dispersion will be appropriately determined depending on the desired ultraviolet absorbing effect, but from the viewpoint of the viscosity, transparency, usability, etc. of the oily dispersion, the total content of the oily dispersion is The content is preferably 30 to 80% by weight, more preferably 40 to 60% by weight based on the total weight of the oily dispersion.

(Polyhydroxy fatty acid)
The polyhydroxy fatty acid used in the present invention is blended with zinc oxide or titanium oxide and OMC, and prevents the aggregation phenomenon of zinc oxide or titanium oxide and OMC in the system of the oily dispersion, while This is for improving the dispersibility of the material. Further, even when an emulsified composition to be described later is produced using an oily dispersion, it is for preventing the aggregation phenomenon of zinc oxide or titanium oxide and OMC and expressing the effect of improving the dispersibility of each material. Is.
Of these polyhydroxy fatty acids, it is preferable to use polyhydroxystearic acid .
The content of polyhydroxy fatty acid in the oily dispersion is appropriately determined according to the content of zinc oxide or titanium oxide or the content of OMC, but is 0 based on the total weight of the oily dispersion. It is preferably 0.05 to 20% by weight, and more preferably 0.1 to 10% by weight based on the total weight of the oily dispersion. When zinc oxide or titanium oxide is used as a reference, it is preferably 0.1 to 30% by weight with respect to zinc oxide or titanium oxide, and among them, 0.2 to 0.2% with respect to zinc oxide or titanium oxide. It is more preferably 20% by weight.

(Light transmittance)
Further, as described above, the oily dispersion according to the present invention can be mixed with ethylhexyl methoxycinnamate without aggregating zinc oxide or titanium oxide, and thus has a high ultraviolet shielding ability even at the stage of the oily dispersion, ultraviolet rays. It will develop absorption capacity.
Specifically, when it is applied as a film having a thickness of 10 μm, it exhibits a high ultraviolet ray shielding ability and ultraviolet ray absorbing ability of 5% or less at 250 to 350 nm in the ultraviolet region. On the other hand, in the visible light range, the light transmittance in the range of 450 nm to 700 nm is 80% or more, which is high transparency.

(Production method)
The method for producing the oily dispersion according to the present invention is not particularly limited, and the oily dispersion can be produced by so-called batch processing in which the respective constituents are blended and mixed at once. In addition, by first mixing zinc oxide or titanium oxide with polyhydroxy fatty acid and then adding OMC and mixing, or by first mixing OMC and polyhydroxy fatty acid and then adding and mixing zinc oxide or titanium oxide. It can also be manufactured.

(Emulsified composition, basic structure)
Next, the emulsion composition according to the present invention will be described.
The emulsion composition according to the present invention has a basic structure containing the above-mentioned oily dispersion according to the present invention. Further, the emulsion composition according to the present invention may be either an O / W type or a W / O type emulsion form, and a multi-phase type emulsion form such as an O / W / O type or W / O / W type. May be

(emulsifier)
The emulsified composition according to the present invention may contain various emulsifiers, if necessary. By thus containing the emulsifier, the emulsified state of the emulsified composition can be maintained more stably. Examples of such emulsifiers include polyether modified silicone and sorbitan fatty acid ester. Of these, PEG-9 dimethicone, PEG-10 dimethicone, and sorbitan isostearate are preferably used.
The content of the emulsifier in the emulsified composition will be appropriately determined according to the content of the oily dispersion to be blended, but is 1 to 30% by weight based on the total weight of the emulsified composition. It is preferable that it is 2 to 20% by weight based on the total weight of the emulsified composition.

(Dispersion medium)
The emulsion composition according to the present invention can also contain a cyclic siloxane or a hydrocarbon oil as a dispersion medium.
By thus containing the dispersion medium, it is possible to obtain an emulsion composition in which zinc oxide or titanium oxide and OMC are further dispersed uniformly without agglomeration and the dispersion state is stabilized.
Here, the cyclic siloxane needs to be a pentamer (so-called D5 oil: decamethylcyclopentasiloxane) or higher because it needs to be a liquid at room temperature. Examples of hydrocarbon oils include liquid paraffin, light liquid isoparaffin, heavy liquid isoparaffin, isobutene, hydrogenated polyisobutene, isohexadecane, isodecane, isododecane, eicosane, isoeicosane, squalane. Of these, decamethylcyclopentasiloxane (D5 oil) or liquid paraffin is preferably used from the viewpoint of excellent dispersibility of zinc oxide or titanium oxide and OMC.
The content of the dispersion medium in the emulsified composition will be appropriately determined according to the content of zinc oxide or titanium oxide, OMC, or polyhydroxy fatty acid to be blended, but the total weight of the emulsified composition is It is preferably 5 to 30% by weight, and more preferably 10 to 20% by weight based on the total weight of the emulsified composition.

(Particle size)
The emulsified composition according to the present invention has zinc oxide or titanium oxide, OMC, and polyhydroxy fatty acid as essential constitutional requirements, so that zinc oxide or titanium oxide and OMC do not cause aggregation in the system. It means that they are dispersed in a stable state.
Specifically, all of the 10% cumulative particle diameter (D10), the 50% cumulative particle diameter (D50), and the 90% cumulative particle diameter (D90) are stably dispersed in an extremely fine particle state of 1 μm or less. It will be.

(Light transmittance)
Further, as described above, the emulsified composition according to the present invention, zinc oxide or titanium oxide and OMC are dispersed in a stable state in the system without causing aggregation, therefore, conventional emulsification using OMC. It exhibits extremely high ultraviolet shielding ability and ultraviolet absorbing ability as compared with the composition.
Specifically, in the case of a film having a thickness of 10 μm, not only does it exhibit extremely high ultraviolet ray shielding ability and ultraviolet ray absorbing ability of 5% or less at 250 to 325 nm, but also the light ray transmitting at 330 to 370 nm. As for the ratio, it also exhibits a high ultraviolet shielding ability of 20% or less and an ultraviolet absorbing ability.
Here, all of zinc oxide, titanium oxide, and OMC exhibit the so-called UVB region (280 to 320 nm) UV-shielding ability and UV-absorbing ability, but the emulsion composition according to the present invention uses zinc oxide, oxidation. Since titanium and OMC can be dispersed in a stable state in the system, not only the ultraviolet ray blocking ability and the ultraviolet ray absorbing ability in the UVB region (280 to 320 nm) but also the fact that zinc oxide or titanium oxide is conventionally aggregated. As a result, the UVA region (320 to 400 nm), which is a region where the sufficient shielding ability and absorbing ability could not be exhibited, also exhibits high ultraviolet shielding ability and ultraviolet absorbing ability.
Furthermore, in the visible light region, the light transmittance at 390 nm is 70% or more, and the light transmittance at 410 nm to 700 nm is 90% or more, which is extremely high transparency.

(Production method)
The method for producing the emulsified composition according to the present invention is not particularly limited, and can be produced by a so-called batch process in which the respective constituents are mixed and mixed at once, but a more stable emulsified state (dispersion) From the viewpoint that an emulsion composition of (state) can be obtained, it is preferable that the aqueous phase component is first mixed, and then the aqueous phase component is added little by little to the oil dispersion and mixed.

(Cosmetics)
The cosmetic according to the present invention contains the oily dispersion according to the present invention or the emulsified composition according to the present invention. Therefore, the high transparency and high transparency (transmission in the visible light range) are maintained. Then, it becomes a cosmetic.
In addition to the above-mentioned oily dispersion of the present invention or the emulsion composition of the present invention, the cosmetics of the present invention may optionally contain various components usually used in cosmetics. Such components include, in addition to the above-mentioned various oils, crystalline cellulose, crosslinked methylpolysiloxane, polyethylene powder, organic powders such as acrylic resin powder, talc, mica, sericite, magnesium carbonate, calcium carbonate, and oxidation. Inorganic powders such as iron, navy blue, ultramarine, titanium mica, titanium sericite, silica (these powder surfaces may be surface-treated with a coupling agent or an inorganic compound to the extent that they do not hinder the application) ), Acrylic acid / alkyl methacrylate copolymers and / or salts thereof, carboxyvinyl polymers and / or salts thereof, thickeners such as xanthan gum and hydroxypropyl cellulose, retinol, retinoic acid, tocopherols, riboflavin, pyridoxine, ascorbic acid, ascorbic acid. Vitamins such as acid phosphate salts , Glycyrrhizinate, glycyrrhetin, ursolic acid, oleanolic acid and other terpenes, estradiol, ethinyl estradiol, estriol and other steroids, phenoxyethanol, parabens, hibitene gluconate, benzalkonium chloride and other preservatives, dimethylaminobenzoic acid Examples thereof include ultraviolet absorbers such as acid esters, cinnamic acid esters, and benzophenones.

  Next, the oil dispersion according to the present invention will be described in detail based on Examples and Comparative Examples. The present invention is not limited to the examples below.

(Example 1)
The surface of zinc oxide as a base material (Taika Co., Ltd .: MZ-500, average primary particle diameter 25 nm) was treated with isostearic acid (10% by weight with respect to zinc oxide), and then treated with 1.575 kg of methoxycinnamate. Example 1 by adding 1.305 kg of ethylhexyl acid salt (manufactured by BASF: Uvinul MC80) and 120 g of polyhydroxystearic acid (manufactured by Nisshin OilliO Group, Ltd .: Saracos HS-6C) and performing dispersion treatment using a sand grinder mill An oily dispersion of was prepared.

(Example 2)
Titanium oxide surface-treated with isostearic acid (Taika Corporation: MT-10EX: average primary particle size 10 nm) 1.200 kg, ethylhexyl methoxycinnamate (BASF: Uvinul MC80) 1.680 kg and polyhydroxystearic acid ( An oily dispersion of Example 2 was prepared by adding 120 g of Saracos HS-6C manufactured by Nisshin Oillio Group Co., Ltd. and performing a dispersion treatment using a sand grinder mill.

(Comparative Example 1)
An oily dispersion of Comparative Example 1 was produced in the same manner as in Example 1 except that polyhydroxystearic acid was not used and the amount of ethylhexyl methoxycinnamate used was changed to 1.425 kg.

(Comparative example 2)
An oily dispersion of Comparative Example 2 was produced in the same manner as in Example 2 except that polyhydroxystearic acid was not used and the amount of ethylhexyl methoxycinnamate used was changed to 1.800 kg.

(Evaluation of transmittance)
Then, the oil dispersions of Examples 1 and 2 and Comparative Examples 1 and 2 were evaluated for transmittance. The evaluation was performed using a spectrophotometer U-4100 (manufactured by Hitachi High-Technologies Corporation). The results are shown in FIGS.
As a result, in the oil-based dispersions of Examples 1 and 2, zinc oxide or titanium oxide and OMC were stably dispersed in the system without agglomeration, and therefore, mainly in the UVB region (specifically, It was found that it has an excellent ultraviolet shielding ability and ultraviolet absorbing ability that almost no ultraviolet ray at 250 to 350 nm is transmitted. In particular, it was found that the oil-based dispersion of Example 1 has excellent ultraviolet ray shielding ability and ultraviolet ray absorbing ability that almost no ultraviolet ray is transmitted not only in the above range but also in the wavelength range of 375 nm. .
Further, it was found that the oil-based dispersions of Comparative Examples 1 and 2 have higher transparency in the visible light region.

  Next, the emulsified composition according to the present invention will be described in detail based on Examples and Comparative Examples. The present invention is not limited to the examples below.

(Example 3, Comparative Example 3, Comparative Example 4)
Oil dispersions of Example 1 and Comparative Example 1, silicone-treated zinc oxide (Taika Co., Ltd .: MZY-303S: average primary particle diameter 35 nm) dispersed in D5 oil (all oil dispersions). The emulsified compositions of Example 3, Comparative Example 3 and Comparative Example 4 were prepared at a compounding ratio shown in Table 1 by using 60% by weight of silicone-treated zinc oxide based on the weight.
Specifically, first, the oil phase components shown in Table 1 were weighed, put in a container, and mixed with a disper. Next, the water phase components shown in Table 1 were weighed, placed in another container, and mixed by a disper. Then, the aqueous phase components prepared in the container in which the oil phase components were mixed were slowly added and mixed with a disper to prepare emulsion compositions of Example 3, Comparative Example 3 and Comparative Example 4.

(Evaluation of emulsified state)
Next, with respect to the emulsified compositions of Example 3, Comparative Example 3 and Comparative Example 4, the emulsified state (dispersed state) was evaluated immediately after the preparation and 7 days after the preparation. The evaluation was performed by observation with an optical microscope. The results are shown in FIGS.
As a result, in the emulsified composition of Example 3, zinc oxide and OMC did not aggregate not only immediately after preparation as shown in FIG. 3 but also after 7 days after preparation as shown in FIG. It was confirmed that they were uniformly dispersed in the system and that the dispersed state was stable.
In addition, the measurement results of the particle size analyzed by the image imaging method of the optical micrograph are shown in Table 2. The emulsion composition of Example 3 has a 10% cumulative particle size (D10) and a 50% cumulative particle size (D50). It was found that the particles were so finely emulsified (dispersed) that they could not be measured (1 μm or less) in all of the 90% cumulative particle diameters (D90), and that they were uniformly dispersed without aggregation.
On the other hand, in the emulsified compositions of Comparative Examples 3 and 4, aggregates were observed immediately after preparation as shown in FIG. 3, and with the passage of time, large particles of μm order could be confirmed as shown in FIG. From this, it was confirmed that the aggregation phenomenon was more advanced. In addition, it was confirmed that aggregation has occurred also in the measurement result of the particle size analyzed by the image imaging method of the optical microscope photograph.

(Evaluation of transmittance)
Next, the transmittance of the emulsified compositions of Example 3, Comparative Example 3 and Comparative Example 4 was evaluated. The evaluation was performed using a spectrophotometer U-4100 (manufactured by Hitachi High-Technologies Corporation). Results are shown in FIG.
As a result, in the emulsified composition of Example 3, since zinc oxide and OMC were uniformly dispersed in the system without agglomeration, as shown in FIG. 5, first, mainly in the UVB region (specifically, It was confirmed that it has an excellent ultraviolet ray shielding ability and ultraviolet ray absorbing ability that almost no ultraviolet ray at 250 to 325 nm) is transmitted. Further, it was confirmed that it has a high ultraviolet shielding ability and an ultraviolet absorbing ability with respect to ultraviolet rays of 330 to 370 nm. That is, in the emulsified composition of Example 3 (the emulsified composition according to the present invention), not only the ultraviolet ray shielding ability of zinc oxide and the ultraviolet ray absorbing ability of OMC are sufficiently exhibited, but also the conventional zinc oxide or oxide It was confirmed that even in the UVA region (320 to 400 nm), which is a region where sufficient shielding ability and absorbing ability could not be exhibited due to titanium aggregation, high ultraviolet shielding ability and ultraviolet absorbing ability were exhibited.
On the other hand, the emulsion compositions of Comparative Example 3 and Comparative Example 4 had an ultraviolet transmittance of about 50% at 330 to 370 nm, resulting in poor ultraviolet shielding ability and ultraviolet absorbing ability.

  From the above results, the oil-based dispersion and the emulsified composition according to the present invention can uniformly disperse zinc oxide or titanium oxide and ethylhexyl methoxycinnamate without aggregating, and stabilize the dispersion state. I found that I could do it. As a result, it was found that it has a high UV protection effect.

  The oily dispersion of the present invention can be used in cosmetics (foundation, sunscreen, etc.), paints, and the like.

Claims (11)

Zinc oxide or titanium oxide having an average primary particle size of 1 to 50 nm, which is surface-treated with isostearic acid or a metal salt of isostearic acid;
Ethylhexyl methoxycinnamate,
An oily dispersion containing a polyhydroxy fatty acid (excluding a surfactant selected from an alkylmethyl taurine salt and / or a phospholipid).
The content of the polyhydroxy fatty acid,
The oily dispersion according to claim 1, which is 0.05 to 20% by weight based on the total weight of the oily dispersion.
The content of ethylhexyl methoxycinnamate,
The oily dispersion according to claim 1 or 2, which is 30 to 80% by weight based on the total weight of the oily dispersion.
The polyhydroxy fatty acid is
The oily dispersion according to any one of claims 1 to 3, which is polyhydroxystearic acid.
An emulsified composition comprising the oily dispersion according to any one of claims 1 to 4.
further,
The emulsified composition according to claim 5, which contains an emulsifier.
further,
The emulsified composition according to claim 5 or 6, which contains a cyclic siloxane or a hydrocarbon oil.
The 10% cumulative particle diameter (D10), the 50% cumulative particle diameter (D50), and the 90% cumulative particle diameter (D90) are all 1 μm or less, and any one of claims 5 to 7. The emulsified composition according to the item.
The light transmittance in 330-370 nm is 20% or less, The emulsion composition as described in any one of Claim 5 to Claim 8 characterized by the above-mentioned.
A cosmetic comprising the oily dispersion according to any one of claims 1 to 4.
A cosmetic comprising the emulsion composition according to any one of claims 5 to 9.