JP3491933B2 - Sunscreen cosmetics - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention improves the re-emulsification property upon contact with water by adding an acrylic acid / alkyl methacrylate copolymer and a water-resistant film-forming agent to improve water resistance and emulsion stability. The present invention relates to an emulsion-type sunscreen cosmetic having excellent properties and safety.

[0002]

2. Description of the Related Art A sunscreen cosmetic used outdoors, especially in summer, is required to have resistance to sweat and water. In conventional sunscreen cosmetics with water resistance, in order to prevent re-emulsification when contacted with water, a lipophilic nonionic surfactant or the like is used to make a W / O type emulsion, or a fatty acid. A large amount of a water resistant film forming agent such as silicone resin has been added to an O / W type emulsion made of soap or a hydrophilic nonionic surfactant.

However, the W / O type emulsion has stickiness, it is difficult to obtain a refreshing feeling of use, and creaming and separation easily occur, which is a problem in stability. On the other hand, when a large amount of a water resistant film forming agent was added to the O / W type emulsion, unfavorable effects on use such as poor elongation and heavy weight occurred. Further, in these emulsions, since a surfactant is used upon emulsification, the surfactant is irritating to the skin or eyes, and there is a problem in safety.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the problems of the conventional water resistant sunscreen cosmetics as described above. That is, the present invention has high water resistance with reduced re-emulsification property, good stability, high safety without using conventional surfactants, and light elongation and feeling of use without stickiness. The present invention provides an emulsion type sunscreen cosmetic.

[0005]

In the present invention, an oily substance is emulsified by using an acrylic acid / alkyl methacrylate copolymer represented by the general formula 1 in place of the conventional surfactant to further improve the water resistance. The above problem could be solved by using the film-forming agent together. That is, the sunscreen cosmetic according to the present invention includes (A) an acrylic acid / alkyl methacrylate copolymer represented by the general formula 1, (B) an oily substance, (C) an ultraviolet absorber and / or titanium oxide, It comprises D) water and (E) a water resistant film forming agent.

[0006] crosslinked acrylic acid-alkyl methacrylate copolymer (A) is a crosslinked copolymer of acrylic acid and alkyl methacrylate, a hydrophilic part due to carboxyl groups, due to the alkyl group It also has a lipophilic portion, has good emulsifying properties, and is commercially available from BF Goodrich under the trade name of PEMULEN. It is also possible to use carboxyvinyl polymer and the like together.

Examples of the oily substance (B) include hydrocarbons such as liquid paraffin and squalane, natural animal and vegetable oils and fats such as olive oil and jojoba oil, octyldodecyl myristate, isopropyl palmitate, and synthetic ester oils such as isopropyl myristate. Liquid oils that are commonly used in cosmetics can be used, but volatile silicone oils such as dimethylpolysiloxane, methylphenylpolysiloxane, and cyclic dimethylpolysiloxane do not remain on the skin when used in cosmetics, so they are oily. It is particularly preferable because it gives a refreshing feeling without use. It is suitable that the compounding amount be 0.5 to 80.0% by weight.

As the ultraviolet absorber (C), those usually used for cosmetics such as paramethoxycinnamates, oxybenzone and the like can be used. Instead of the ultraviolet absorber, titanium oxide having an ultraviolet scattering effect may be dispersed and blended, or these may be used in combination.

As the water resistant film forming agent (E), a silicone resin such as trimethylsiloxysilicic acid or silylated pullulan can be used. The amount of these water-resistant film-forming agents to be compounded is appropriately in the range that the weight ratio (A) / (E) of (A) to the acrylic acid / alkyl methacrylate copolymer is 8/2 to 1/9. .

[0010]

The emulsion-type sunscreen cosmetic according to the present invention has good emulsion stability and does not show creaming or separation even after long-term storage. When applied to the skin, it has low re-emulsification property when it comes into contact with water, exhibits excellent water resistance and water repellency, and has good makeup retention. In addition, it has low irritation to the skin and eyes and is excellent in safety. Furthermore, it is not sticky, stretches lightly, and has good usability.

The sunscreen cosmetic composition according to the present invention is emulsified cosmetic composition having very high water resistance. It can be provided as products such as emulsion type makeup base cream for sunscreen and liquid foundation for sunscreen.

[0012]

EXAMPLES The features of the present invention will be described in detail with reference to Examples.

The formulations of Examples and Comparative Examples of the present invention are shown in Table 1. In the example, the components (4) to (7) in Table 1 were mixed and homogenized, and the component (1) dissolved and thickened by a part of the component (9) was added thereto, and the shear force was applied by a homogenizer or the like. To emulsify, neutralize by adding dissolved component (8) to the rest of component (9),
Prepare by mixing and homogenizing. Comparative Example 1 is a W / O type emulsion obtained by emulsifying a silicone oil using sorbitan sesquioleate, which is a lipophilic nonionic surfactant, and the components (2) and ( It is obtained by gradually adding the component (9) to a mixture of 4) to 6) and homogenization, and mixing and homogenization. Comparative Example 2 is an O / W type emulsion obtained by emulsifying silicone oil with polyoxyethylene sorbitan monooleate, which is a hydrophilic nonionic surfactant, and a water resistant film forming agent is added to the emulsion. And ingredients (3)
(7) is mixed and homogenized, and the component (9) is gradually added to the mixture and homogenized. And Comparative Example 3 is an emulsion obtained by emulsifying silicone oil using an acrylic acid / alkyl methacrylate copolymer, but does not contain a water-resistant film forming agent, and is a component (4) to 6). Mix,
To the homogenized product, the component (1) dissolved and thickened by a part of the component (9) was added, and a shearing force was applied by a homogenizer etc. to emulsify it, and then dissolved in the rest of the component (9) ( 8) is added, neutralized, mixed and homogenized. The pH of each of the emulsions of Examples and Comparative Examples was adjusted to 7.5. In addition, as the component (1) in Table 1,
A commercially available packet from BF Goodrich.
Mullen TR-1 (PEMULEN TR-1) was used.

[Table 1]

With respect to the examples and comparative examples of the present invention, water repellency, re-emulsification property, usability, safety and stability were evaluated.

(1) Water repellent 0.1 g of each sample was taken on a slide glass, uniformly applied, dried and evaluated by measuring the contact angle. The results are shown in Table 2.

[Table 2]

(2) Re-emulsification property 0.1 g of each sample was placed on a slide glass, uniformly applied and dried, and placed in a linatsu type tester, dipped in 700 ml of tap water for 5 minutes, then dried and contacted. The angle was measured and evaluated. The results are also shown in Table 2.

(3) Usability and safety Male and female panelists total 2
Each sample was blindly used by 0 people and sensory-evaluated for elongation during application, presence of stickiness after application, and presence of irritation. Regarding growth, "heavy", "slightly heavy", "normal", "slightly", "light", and "presence", "somewhat", "neither", or "somewhat" regarding presence / absence of stickiness “No”, “No”, and “I feel very strongly”, “I feel a little strongly” regarding irritation,
The evaluation was made in five levels: "feel", "delicately feel", and "not feel". The results are shown in Table 3 by the number of panelists used for each evaluation.

[Table 3]

The safety was also evaluated by a patch test. A closed patch test for 48 hours was performed on the back of each sample using 30 panelists. The result was judged according to the judgment criteria shown in Table 4 and was 30
The average value of the skin irritation index of each name is shown in Table 5.

[Table 4]

[Table 5]

(4) Stability For each sample, (a) -20 ° C
If the procedure of freezing in and then thawing is repeated 5 times,
(B) When left standing for 3 months while changing the storage temperature in the range of -10 ° C to 40 ° C, (c) When left at 40 ° C for 3 months, (d) Still at 50 ° C for 3 months. When the sample was placed, (e) Changes in the emulsified state in each case when left standing at 5 ° C. for 3 months were observed and evaluated. The results are shown in Table 6.

[Table 6]

As is clear from Table 2, the examples of the present invention and Comparative Example 1 have a larger contact angle than Comparative Examples 2 and 3 and are shown to have extremely excellent water repellency. . In addition, in Examples and Comparative Example 1 of the present invention, the contact angle measured after immersion in water was slightly smaller than that before immersion in water, but Comparative Example 2 and Comparative Example 3
Has decreased significantly. This indicates that the examples of the present invention have low re-emulsification property and high water resistance. On the other hand, Comparative Examples 2 and 3 had high maximum emulsification properties and low water resistance.

From Table 3, it is shown that in the examples of the present invention, the elongation during application is light, there is no stickiness during use, and there is no irritation. In Comparative Example 1 and Comparative Example 2, most of the panelists evaluated that the elongation was heavy and sticky. Also, a slight irritation was observed. But in Comparative Example 3 had a good reputation for growth and irritation, for the sticky little evaluation is rather poor, had some of the stickiness was observed. The patch test results shown in Table 5 also confirmed that the examples of the present invention had a very low skin irritation index and were excellent in safety.

From Table 6, it was shown that in Examples of the present invention and Comparative Example 3, no change in the emulsified state was observed under each storage condition and the stability was excellent. On the other hand, Comparative Example 1
Also, in Comparative Example 2, remarkable deterioration of the emulsified state was observed.

As described above, the embodiment of the present invention is
It was excellent in terms of re-emulsification, usability, safety and stability. On the other hand, in Comparative Example 1, the re-emulsification property was small, but the usability and stability were poor, and the safety was not evaluated very well. In Comparative Example 2, good evaluation was not obtained in each item, and in Comparative Example 3, stability and safety were good, but re-emulsifying property was large, and makeup retention was predicted to be poor.

[0024]

As described in detail above, according to the present invention, it has excellent water repellency, has good water resistance, has no re-emulsification property, and has a good feeling of use with light elongation and lightness.
Furthermore, it was possible to provide an emulsion-type sunscreen cosmetic that is highly safe, has no irritation, and is extremely stable.

Continuation of the front page (56) Reference JP-A-5-194171 (JP, A) JP-A-4-39312 (JP, A) JP-A-54-41337 (JP, A) JP-A-3-217420 (JP , A) JP 4-132736 (JP, A) JP 5-59069 (JP, A) JP 5-178865 (JP, A) JP 4-368392 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) A61K ^7/ 00-7/50

Claims (3)

(57) [Claims] 1. A mixture of (A) a cross-linking type acrylic acid / methacrylic acid copolymer, (B) an oily substance, (C) an ultraviolet absorber and / or titanium oxide, and (D) water, followed by emulsification and then neutralization. And (E) trimethylsiloxysilicic acid represented by the formula 2, and
And / or one or two selected from silylated pullulan
A sunscreen cosmetic characterized by containing a water-resistant film forming agent . [Chemical 2] 2. The ratio (A) / (E) of the compounding amounts of (A) and (E) is 8/2 to 1/9 by weight.
Sunscreen cosmetics described in. 3. The blending amount of the oily substance (B) is 0.5 to 8
The sunscreen cosmetic according to claim 1 or 2, which is 0.0% by weight.