JP6812762B2 - Gel elastomer composition and cosmetic gel sheet using it - Google Patents

Description

The present invention relates to a gel elastomer composition having an appropriate hardness and capable of exhibiting an excellent emollient effect without causing stickiness, and a cosmetic gel sheet using the same.

Conventionally, gel elastomers in which an oil agent is mixed with a styrene-based thermoplastic elastomer have been used for various products requiring elasticity. For example, shock absorbers for foot care such as insoles for shoes and pads for hallux valgus, shock absorbers for sports such as knee pads and elbow pads, and pack materials, compresses, and air fresheners that utilize the sustained release of oils. It is used in various fields such as. Among them, pack materials used as cosmetics have gel elastomer impregnated with active ingredients attached to the skin, so that oils and active ingredients permeate the skin, which is effective in moisturizing the skin and improving dry skin. Can be demonstrated.

On the other hand, oils such as hydrocarbon oils and ester oils have an emollient effect and are blended in various cosmetics, but liquid oils are very difficult to handle because they drip from fingers and cotton during use. In creamy oils, a large amount of surfactant is used when blending into an emulsified dosage form, so that ingredients other than the active ingredient also penetrate into the skin.

Therefore, Patent Document 1 discloses a composition in which a styrene-based thermoplastic elastomer, a hydrocarbon oil, and olive oil are blended as a gel-like pack material. This composition can be impregnated with a large amount of beauty essence, is less irritating to the skin, and is said to be excellent in releasing beauty ingredients. However, low molecular weight styrene-based thermoplastic elastomers and di Since it contains a block copolymer, if a large amount of an oil agent having an emollient effect is blended, it may become too soft or sticky.

Further, Patent Document 2 discloses a gel elastomer composition containing a styrene-based thermoplastic elastomer, a hydrocarbon oil, and cetyl 2-ethylhexanoate. It is said that this composition can obtain excellent processability and at the same time a refreshing feel by blending an ester oil, but the load applied to the gel elastomer composition is applied. In such cases, a sufficient amount of oil was not released and a satisfactory emollient effect could not be obtained.

Japanese Unexamined Patent Publication No. 2012-12374 Japanese Unexamined Patent Publication No. 2000-281850

The present invention uses a gel elastomer composition having an appropriate hardness and capable of exhibiting an excellent emollient effect without causing stickiness by easily releasing an oil agent even under a light load, and a gel elastomer composition thereof. An object of the present invention is to provide a cosmetic gel sheet that is suitable for moisturizing and measures against dry skin.

By blending a styrene-based thermoplastic elastomer having a molecular weight within a specific range, an aliphatic hydrocarbon oil having a viscosity within a specific range, and a fatty acid triglyceride having a carbon number within a specific range, the present inventors , The present invention has been completed.

That is, one aspect of the present invention (Aspect 1) is a styrene-based thermoplastic elastomer (A1) having a weight average molecular weight of 100,000 or more and less than 180,000 and a block copolymer of triblock or more, and a weight average molecular weight. Styrene-based thermoplastic elastomer (A2) composed of block copolymers of 180,000 or more and 300,000 or less and triblock or more, with a mass ratio of (A1) / (A2) = 95/5 to 50/50. With respect to 100 parts by mass of the styrene-based thermoplastic elastomer mixture (A) contained in the above, 500 to 4800 parts by mass of the aliphatic hydrocarbon oil (B) having a kinematic viscosity at 37.8 ° C. of 5 to 50 mm ² / s, 20 It is a gel elastomer composition containing 60 to 1000 parts by mass of a fatty acid triglyceride (C) having 8 to 22 carbon atoms which is liquid at ° C.

Further, in another aspect (aspect 2) of the present invention, in the gel elastomer composition of the above aspect 1, the block copolymer has two or more block components composed of styrene-based hard segments in the molecular chain. It is an elastomer composition.

Further, in still another aspect (aspect 3) of the present invention, in the gel elastomer composition of the above aspect 2, at least both terminal block components in the molecular chain of the block copolymer are blocks composed of the styrene-based hard segment. It is a gel elastomer composition which is an ingredient.

Further, in still another aspect (aspect 4) of the present invention, in the gel elastomer composition of any one of the above aspects 1 to 3, the fatty acid triglyceride (C) is a saturated fatty acid triglyceride (c1) having 8 to 12 carbon atoms. ) And the unsaturated fatty acid triglyceride (c2) having 14 to 22 carbon atoms in a mass ratio of (c1) / (c2) = 95/5 to 50/50, which is a gel elastomer composition.

Further, another aspect (aspect 5) of the present invention is a cosmetic gel sheet using the gel elastomer composition of any one of the above aspects 1 to 4.

The present invention can provide a gel elastomer composition having an appropriate hardness and capable of exhibiting an excellent emollient effect without causing stickiness by easily releasing an oil agent even under a light load. it can. In addition, the cosmetic gel sheet of the present invention using the gel elastomer composition can evenly adhere an oil agent having an emollient effect to the skin surface by simply lightly applying the gel sheet to the skin, thus moisturizing the skin. It can be suitably used as a measure against dry skin.

Hereinafter, the gel elastomer composition of the present invention and a cosmetic gel sheet using the same will be described in detail.

The styrene-based thermoplastic elastomers (A1, A2) used in the present invention are block copolymers of triblock or more containing styrene-based hard segments and soft segments, and preferably have a block component composed of styrene-based hard segments as a molecular chain. It is a block copolymer having two or more in it, and more preferably, a block copolymer in which at least both terminal block components in the molecular chain are block components composed of the styrene-based hard segment. The styrene-based hard segment is not particularly limited, and for example, polystyrene, poly (α-methylstyrene), poly (o-methylstyrene), poly (m-methylstyrene), poly (p-methylstyrene), and the like. Examples include styrene-based polymers. The soft segment is not particularly limited, and examples thereof include olefin polymers such as polyethylene, polypropylene, polybutylene, polybutadiene, and polyisoprene.

The copolymer used as the styrene-based thermoplastic elastomer (A1, A2) is not particularly limited as long as it is a styrene-based block copolymer of triblock or higher, but for example, a styrene-butadiene-styrene block copolymer (SBS). ), Styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-isoprene-butylene-styrene block copolymer (SIBS), styrene-isoprene-styrene block copolymer (SIS), styrene-ethylene-propylene -Styrene block copolymer (SEPS) and styrene-ethylene-ethylene-propylene styrene block copolymer (SEEPS) and the like can be mentioned. Among these, preferably, styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-ethylene-propylene-styrene block copolymer (SEPS), styrene-ethylene-ethylene-propylene-styrene block copolymer. (SEEPS), and a combination of two or more of these. Furthermore, among these, styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-ethylene-propylene-styrene block copolymer (SEPS), from the viewpoint of gel hardness after molding into a sheet or the like. And styrene-ethylene-ethylene-propylene styrene block copolymer (SEEPS) are preferred. When a diblock copolymer is used as the styrene-based thermoplastic elastomer (A1, A2), the interaction (π-π stacking) of the styrene-based hard segments is weakened, so that the hardness of the gel is sufficiently obtained. There is a risk that it will not be possible. In the styrene-based thermoplastic elastomer, a network-like network structure is formed by a plurality of agglutinating domains formed by the interaction of the styrene-based hard segments and olefin-based soft segments connecting the plurality of agglutinating domains. Therefore, it is considered that the function as an elastic body is exhibited. Further, it is considered that such a network-like network structure has a function of appropriately releasing and retaining an oil agent (that is, an aliphatic hydrocarbon oil (B) and a fatty acid triglyceride (C)) described later. Be done.

The block copolymer preferably contains 10 to 50% by mass of a styrene block component and about 50 to 90% by mass of an olefin block component, more preferably 15 to 40% by mass of a styrene block component and 60 to 85% by mass. Contains olefinic block components. When the amount of the styrene-based block component is less than 10% by mass, the amount of the styrene-based block component forming the aggregated domain is small, so that the styrene-based thermoplastic elastomer is difficult to form the above-mentioned network structure. .. On the other hand, when the amount of the styrene-based block component exceeds 50% by mass, the amount of oil and the like that can be retained decreases, and the amount of aggregated domains formed by the styrene-based hard segment increases, so that the gel after molding May become hard.

In the present invention, the styrene-based thermoplastic elastomer mixture (A) is composed of a mixture of two types of styrene-based thermoplastic elastomers (A1 and A2) having different weight average molecular weights.

Of the two types of styrene-based thermoplastic elastomers (A1 and A2), the styrene-based thermoplastic elastomer (A1) having the lower weight average molecular weight is referred to as "low molecular weight styrene-based thermoplastic elastomer (A1)". The weight average molecular weight is in the range of 100,000 or more and less than 180,000, preferably in the range of 100,000 to 150,000. If this weight average molecular weight is less than 100,000, the hardness of the gel will decrease (ie, the gel will become too soft). Further, of the two types of styrene-based thermoplastic elastomers (A1 and A2), the styrene-based thermoplastic elastomer (A2) having the higher weight average molecular weight (hereinafter, "high molecular weight styrene-based thermoplastic elastomer (A2)"". The weight average molecular weight is in the range of 180,000 or more and 300,000 or less, preferably in the range of 220,000 to 280,000. If the weight average molecular weight exceeds 300,000, the hardness of the gel may decrease (that is, the gel may become too soft) or stickiness may occur.

The styrene-based thermoplastic elastomer mixture (A) has a dispersity (that is, a ratio of weight average molecular weight (Mw) to number average molecular weight (Mn) (Mw / Mn)) within a range of 1.25 to 1.60. It is preferable to have. When the degree of dispersion is within such a range, the gel tends to have an appropriate hardness, and the oil agent tends to be released in an appropriate amount.

The weight average molecular weight (Mw) of each of the two types of styrene-based thermoplastic elastomers (A1, A2) and the styrene-based thermoplastic elastomer mixture (A), and the dispersity (Mw) of the styrene-based thermoplastic elastomer mixture (A). / Mn) can be determined by GPC measurement under the following conditions using tetrahydrofuran (THF) as a mobile phase and by polystyrene conversion.

[GPC measurement conditions]
Equipment: GPC-8220 (manufactured by Tosoh Corporation)
Column: Shodex LF-804 (manufactured by Showa Denko KK)
Temperature: 40 ° C
Solvent: THF
Flow velocity: 1.0 ml / min
Sample concentration: 0.05 to 0.6% by mass
Injection volume: 0.1 ml

As described above, in the present invention, a mixture of two types of styrene-based thermoplastic elastomers (A1 and A2) having different weight average molecular weights is used, and the blending amount thereof is the same as that of the low molecular weight styrene-based thermoplastic elastomer (A1). The mass ratio of the high molecular weight styrene-based thermoplastic elastomer (A2) is in the range of (A1) / (A2) = 95/5 to 50/50, preferably in the range of 90/10 to 60/40. More preferably, it is in the range of 80/20 to 70/30. In the mass ratio, if the blending ratio of the low molecular weight styrene-based thermoplastic elastomer (A1) exceeds 95, the hardness of the gel becomes insufficient, and if the blending ratio is less than 50, it is released from the gel. There is a risk that the amount of oil released will decrease.

The gel elastomer composition of the present invention further comprises an aliphatic hydrocarbon oil (B) having a kinematic viscosity of 5 to 50 mm ² / s at 37.8 ° C. The aliphatic hydrocarbon oil (B) used in the present invention is not particularly limited as long as it is an aliphatic compound composed of carbon and hydrogen, and is either a saturated aliphatic hydrocarbon oil or an unsaturated aliphatic hydrocarbon oil. May be good.

Examples of the saturated aliphatic hydrocarbon oil include liquid paraffin, hydrogenated polyisobutene, α-olefin oligomer, squalane and the like. Examples of unsaturated aliphatic hydrocarbon oils include squalene and polybutene. Among these, hydrogenated polyisobutene can be particularly preferably used because it does not cause stickiness due to the released oil agent.

The aliphatic hydrocarbon oil (B) has a kinematic viscosity at 37.8 ° C. is in the range of 5 to 50 mm ² / s, preferably in the range of 10 to 30 mm ² / s, more preferably 10 to 20 mm ² It is within the range of / s. If the kinematic viscosity is less than 5 mm ² / s, the aliphatic hydrocarbon oil (B) tends to volatilize during the production of the gel elastomer composition, so that the physical properties of the gel elastomer composition may vary. On the other hand, when this kinematic viscosity exceeds 50 mm ² / s, the gel after molding becomes hard and the amount of oil released decreases. The kinematic viscosity of the aliphatic hydrocarbon oil (B) is measured at a test temperature of 37.8 ° C. using a Canon Fenceke viscous meter according to "5. Kinematic viscosity test method" of JIS K 2283: 2000. Can be obtained by

The blending amount of the aliphatic hydrocarbon oil (B) is in the range of 500 to 4800 parts by mass, preferably 800 to 3000 parts by mass with respect to 100 parts by mass of the styrene-based thermoplastic elastomer mixture (A). It is within the range, more preferably within the range of 1000 to 1500 parts by mass. If this blending amount is less than 500 parts by mass, the gel after molding becomes hard. On the other hand, if the blending amount exceeds 4800 parts by mass, the gel becomes too soft and it becomes difficult to maintain the shape after molding.

The gel elastomer composition of the present invention is liquid at 20 ° C. (ie, room temperature) and further contains a fatty acid triglyceride (C) having 8 to 22 carbon atoms. The fatty acid triglyceride used in the present invention may be, for example, a dehydration synthesis reaction of glycerin and one or more kinds of fatty acids without a catalyst, or a transesterification reaction of glycerin and an alcohol ester of one or more kinds of fatty acids. It can be obtained by doing so.
Examples of the fatty acid triglyceride that can be used in the present invention include saturated fatty acid triglyceride (c1) having 8 to 12 carbon atoms using saturated fatty acids such as capric acid, caprylic acid, and lauric acid. Specific examples of commercially available products include Panaseto (trade name) manufactured by NOF CORPORATION, Coconade (trade name) manufactured by Kao Corporation, and ODO of Nisshin Oillio Co., Ltd.
Further, examples of the fatty acid triglyceride that can be used in the present invention include unsaturated fatty acid triglycerides (c2) having 14 to 22 carbon atoms, such as triglycerides of oleic acid. Specific examples of commercially available products include olive oil, soybean oil, camellia oil, sunflower oil, rapeseed oil, sesame oil, corn oil, cottonseed oil, safflower oil, jojoba oil and the like. Among these, olive oil, camellia oil and sunflower oil containing oleic acid triglyceride in a proportion of 70% by mass or more are particularly preferable.

The blending amount of the fatty acid triglyceride (C) is in the range of 60 to 1000 parts by mass, preferably in the range of 80 to 900, more preferably in the range of 80 to 900 parts by mass with respect to 100 parts by mass of the styrene-based thermoplastic elastomer mixture (A). Is in the range of 100 to 700 parts by mass. If the blending amount is less than 60 parts by mass, the amount of the oil agent released decreases, while if it exceeds 1000 parts by mass, the amount of the oil agent released becomes too large and stickiness may occur.

Further, in the present invention, as the fatty acid triglyceride (C), a mixture of the above-mentioned two types of fatty acid triglycerides (c1 and c2) having different carbon atoms can be used. As a specific compounding amount, a saturated fatty acid triglyceride (c1) having 8 to 12 carbon atoms and an unsaturated fatty acid triglyceride (c2) having 14 to 28 carbon atoms are used from the viewpoint of improving the hardness and emollient effect of the gel. It is preferably contained in a mass ratio within the range of (c1) / (c2) = 95/5 to 50/50.

The gel elastomer composition of the present invention is added to the styrene-based thermoplastic elastomer mixture (A), the aliphatic hydrocarbon oil (B) and the fatty acid triglyceride (C) in order to further improve the effect of the present invention. , Silicone oil (D) may be further contained. The blending amount of the silicone oil (D) is preferably in the range of 5 to 60 parts by mass with respect to 100 parts by mass of the styrene-based thermoplastic elastomer mixture (A). When the blending amount of the silicone oil (D) is within such a range, an appropriate amount of the oil agent can be released even when the content of the oil agent in the gel elastomer composition is small, so that no stickiness occurs. Further excellent emollient effect can be exhibited.

Further, the gel elastomer composition of the present invention is the styrene-based thermoplastic elastomer mixture (A) and the aliphatic hydrocarbon in order to further enhance the effect when immobilized on various substrates and used as a cosmetic gel sheet or the like. In addition to the hydrogen oil (B) and the fatty acid triglyceride (C), an aliphatic alcohol (E) having 12 to 24 carbon atoms may be further contained. Examples of the aliphatic alcohol (E) having 12 to 24 carbon atoms include lauryl alcohol, myristyl alcohol, palmityl alcohol, stearyl alcohol, behenyl alcohol, and mixtures thereof. Among them, the melting point is 20 ° C. to 100. Those in the range of ° C. are preferable. The blending amount of the aliphatic alcohol (E) having 12 to 24 carbon atoms is preferably in the range of 50 to 500 parts by mass with respect to 100 parts by mass of the styrene-based thermoplastic elastomer mixture (A). When the melting point and the blending amount of the aliphatic alcohol (E) having 12 to 24 carbon atoms are in the above ranges, the solidification temperature of the gel elastomer composition becomes high, so that the gel elastomer composition in a molten state is used as various base materials. The gel can be effectively immobilized on the substrate when applied on top and solidified by cooling (ie, when forming the gel). As a result, the effect of the present invention can be further enhanced without causing stickiness even at a temperature higher than room temperature.

The gel elastomer composition of the present invention can be produced by adding the above-mentioned various components at the same time or in any order and melting and mixing them. The method of melt-mixing is not particularly limited, and any known method can be adopted. Examples of such a method include a method using a mixing device such as a single-screw extruder, a twin-screw extruder, a roll, a Banbury mixer, various kneaders, and a compounding kettle.

The gel elastomer composition of the present invention is excellent in hardness and elongation, and has an appropriate release property (sustained release property) of an oil agent. Therefore, while suppressing adhesion to a molding apparatus, extrusion molding, injection molding, dipping molding, etc. It is possible to mold by any molding method of. Further, since the gel elastomer composition of the present invention contains a larger amount of the low molecular weight styrene-based thermoplastic elastomer (A1) than the high-molecular-weight styrene-based thermoplastic elastomer (A2), the temperature condition is around 100 ° C. Since it exhibits an appropriate fluidity, it can be molded on various substrates such as paper, cloth, olefin resin, and PET resin.

As a specific application of the gel elastomer composition of the present invention, it can be applied to a cosmetic gel sheet such as a pack, a poultice, an air freshener, etc., which utilizes the sustained release property of an oil agent. In addition, the face (skin, etc.) of esthetic practice dolls, healthcare-related products, shoe insoles, foot care shock absorbers to relieve pain caused by hallux valgus, ingrown nails, etc., massage tools, etc. For head parts, toy parts, miscellaneous goods, medical shock absorbers to prevent rubbing between artificial legs and skin, cleaning products that apply oil while adsorbing dust and dirt from daily necessities such as floors. It is also possible to apply.

In addition, the cosmetic gel sheet using the gel elastomer composition of the present invention can be widely applied mainly for cosmetic applications, but it is also good for the skin of uneven parts such as elbows and knees, which are easily dried. Since it can be attached to, it is particularly useful for moisturizing such areas and improving dry skin. The method of using the cosmetic gel sheet of the present invention is not particularly limited, but for example, a moisturizing cream is applied in advance to a site to be applied such as knees and elbows, and the cosmetic gel sheet of the present invention is attached thereto to moisturize the skin. The permeability of the component can be further improved. Further, by incorporating a beauty ingredient such as a beauty essence into the gel elastomer composition of the present invention, the beauty ingredient and the oil agent are gradually released, and better skin care can be performed.

The gel elastomer composition of the present invention may contain other additives used in general cosmetics as long as the effects of the present invention are not impaired. Examples of such additives include antioxidants, light stabilizers, colorants, pigments, fragrances and the like.

Hereinafter, the present invention will be described in more detail by exemplifying examples and comparative examples of the present invention, but the present invention is not limited to such examples.

In producing the gel elastomer compositions of Examples and Comparative Examples of the present invention, the following commercially available products were used as various compounding components.

1) Styrene-based thermoplastic elastomers (A1, A2)
a) Low molecular weight styrene-based thermoplastic elastomer (A1)
・ Septon 8004 (Styrene-ethylene-butylene-styrene block copolymer (SEBS) with Mw of 110,000, manufactured by Kuraray Co., Ltd.)
b) Low molecular weight styrene-based thermoplastic elastomer (A1')
-Clayton G1652 (styrene-ethylene-butylene-styrene block copolymer (SEBS) with Mw of 80,000, manufactured by Kraton Polymer Co., Ltd.)

c) High molecular weight styrene-based thermoplastic elastomer (A2)
-Clayton G1654 (Styrene-ethylene-butylene-styrene block copolymer (SEBS) with Mw of 200,000, manufactured by Kraton Polymers)
Septon 2005 (Styrene-ethylene-propylene-styrene block copolymer (SEPS) with Mw of 260,000, manufactured by Kuraray Co., Ltd.)

2) Oil
a) Aliphatic hydrocarbon oil (B)
・ Pearl Dream EX (hydrogenated polyisobutene with kinematic viscosity at 37.8 ° C of 10 mm ² / s, manufactured by NOF CORPORATION)
・ Pearl Dream 6 (hydrogenated polyisobutene with kinematic viscosity at 37.8 ° C of 20 mm ² / s, manufactured by NOF CORPORATION)
b) Aliphatic hydrocarbon oil (B')
-Liquid paraffin (liquid paraffin with kinematic viscosity at 37.8 ° C of 75 mm ² / s, manufactured by MORESCO Co., Ltd.)

c) Fatty acid triglyceride (C)
-Panasate 810S (capric acid, caprylic acid fatty acid triglyceride, manufactured by NOF CORPORATION)
・ Olive oil refined (olive oil, manufactured by DSP Gokyo & Food Chemical Co., Ltd.)
・ Rapeseed white shark oil (rapeseed oil, manufactured by Showa Sangyo Co., Ltd.)

d) Other ester oil (C')
・ Salasco 816T (cetyl 2-ethylhexanoate, manufactured by Nisshin Oillio Group Co., Ltd.)

3) Other oils (D)
SH200-100cs (dimethylpolysiloxane with kinematic viscosity at 25 ° C of 100 mm ² / s, manufactured by Toray Dow Corning Co., Ltd.)

4) Other oils (E)
・ NAA-45 (stearyl alcohol with melting point of 58.5 ° C, manufactured by NOF CORPORATION)

[Examples 1 to 12, Comparative Examples 1 to 6]
1. 1. Production of gel elastomer composition
The above-mentioned various compounding components were charged into a separable flask at each compounding amount shown in Table 1 below, and the contents were melt-mixed at 130 ° C. for 5 hours while stirring the contents, and then cooled to compare Examples 1 to 12. Each gel elastomer composition of Examples 1 to 6 was obtained. The characteristics of each of the obtained gel elastomer compositions were evaluated by the following various test methods. The composition and physical properties (weight average molecular weight and dispersity) of each gel elastomer composition are shown in Table 1, and the evaluation results by various test methods are shown in Tables 2 and 3.

2. 2. Evaluation of gel elastomer composition
(1) Physical property test (i) Hardness Using the gel elastomer composition obtained as described above, a test piece made of a columnar gel having a diameter of 40 mm and a thickness of 8 mm was prepared. The prepared test piece was set in a small tabletop tester EzTest (manufactured by Shimadzu Corporation) equipped with a stainless steel compression jig with a diameter of 120 mm, and the test piece was compressed by 4 mm at a speed of 5 mm / min. The force (N) was measured. The measured values were evaluated according to the following criteria. The measurement results and evaluation results are shown in Table 2 below.
◯: 10N or more, 40N or less ×: Less than 10N or more than 40N

○： 質量増加率（放出量）が２％以上１０％以下
×： 質量増加率（放出量）が２％未満又は１０％を超える (Ii) Release property Using the obtained gel elastomer composition, a test piece composed of a columnar gel having a diameter of 40 mm and a thickness of 8 mm was prepared. A commercially available tissue paper (a set of two) whose mass (W ₁ ) has been measured in advance is placed on the prepared test piece, and a load of 10 g is applied from the top of the tissue paper to room temperature (23 ° C.). After leaving it for 24 hours, the tissue paper was removed and its mass (W ₂ ) was measured. Then, from the mass (W ₁ ) measured in advance and the mass (W ₂ ) measured after being left for 24 hours, the mass increase rate (%) of the tissue paper is calculated based on the following formula (1). Further, the mass increase rate (%) was evaluated as the amount released according to the following criteria. The measurement results and evaluation results are shown in Table 2 below.

◯: Mass increase rate (release amount) is 2% or more and 10% or less ×: Mass increase rate (release amount) is less than 2% or exceeds 10%

(2) Sensory Test The gel elastomer composition obtained as described above was hot-pressed under the conditions of a set temperature of 120 ° C. and a pressure of 10 kg / cm ² , to prepare a gel sheet having a thickness of 60 mm × 60 mm × 1 mm, and then this The gel sheet was laminated with a non-woven fabric made of polyethylene (PE) to prepare a laminated gel sheet for a sensory test. After the laminated gel sheet prepared in this manner was left at 23 ° C. overnight, the "softness" and "stickiness" were evaluated with respect to the tactile sensation when the surface of the laminated gel sheet was reciprocated 10 times to the left and right with a finger. Further, in Examples 8 to 12, "softness" and "stickiness" were also evaluated for the laminated gel sheet left at 40 ° C. overnight. In addition, a laminated gel sheet left at 23 ° C. overnight was attached to the back of the hand and left for 15 minutes, and then the skin condition was confirmed and the "emollient effect" was evaluated. These evaluations were performed by 10 subjects, and a questionnaire was conducted according to each of the following evaluation criteria. The results of this questionnaire were evaluated by the total score of 10 people.
In the evaluation of the above-mentioned emollient effect, it is meant that the emollient effect means "the action of softening the skin by suppressing the evaporation of water from the skin by the action of the oily film". Explained in advance.

(I) Softness 3 points: Elastic and soft 2 points: Elastic but hard 1 point: Non-elastic and hard, or non-elastic and soft

(Ii) Sticky 3 points: Fingers are not sticky with oil 2 points: Fingers are slightly sticky with oil 1 point: Fingers are sticky with oil

(Iii) Emollient effect 3 points: Emollient effect can be felt
2 points: The emollient effect is not felt so much 1 point: The emollient effect is not felt at all

The total score of each of the sensory tests (i) to (iii) above was determined according to the following criteria. The total score and evaluation result of each sensory test are shown in Table 2 below (the numbers in parentheses in the table indicate the total score of each sensory test).
<Evaluation of total points>
◎: Total score is 26 points or more ○: Total score is 21 points or more, less than 26 points
Δ: Total score is 15 points or more and less than 21 points ×: Total score is less than 15 points

As shown in Table 2, the gel elastomer compositions of the present invention of Examples 1 to 12 showed good results in all evaluations of the physical characteristic test and the sensory test (room temperature (23 ° C.)). In particular, since the gel elastomer composition of Example 8 is excellent in the release property of the oil agent, the emollient effect was highly evaluated even in the sensory test. Further, since the gel elastomer composition of Example 9 is excellent in the release property of the oil agent despite the small amount of the fatty acid triglyceride (C), the emollient effect is highly evaluated even in the sensory test. Was done. Further, as shown in Table 3, in Examples 10 to 12 to which the other oil agent (E) was added, in addition to the high evaluation at room temperature (23 ° C.), "softness" was also obtained at a temperature higher than room temperature (40 ° C.). Highly evaluated for "stickiness".

On the other hand, since the gel elastomer composition of Comparative Example 1 contained only a low molecular weight styrene-based thermoplastic elastomer (A1) as the styrene-based thermoplastic elastomer, the hardness of the gel was hard. Further, in the gel elastomer composition of Comparative Example 2, the viscosity of the aliphatic hydrocarbon oil (B) was out of the range of 5 to 50 mm ² / s and did not contain the fatty acid triglyceride (C), so that the gel was hard. The hardness became hard and the amount of oil released became too small, and even in the sensory test, the hardness of the gel was hard and the emollient effect was not felt. In the gel elastomer composition of Comparative Example 3, the mass ratio of the low molecular weight styrene-based thermoplastic elastomer (A1) to the high-molecular-weight styrene-based thermoplastic elastomer (A2) is (A1) / (A2) = 95/5 to 5 Since it was outside the range of 50/50, the hardness of the gel was too soft. In the gel elastomer composition of Comparative Example 4, the weight average molecular weight of the low molecular weight styrene-based thermoplastic elastomer mixture (A1') was outside the range of 100,000 or more and less than 180,000, so that the hardness of the gel became too soft. In addition, the amount of the oil released was too large, and stickiness was felt in the sensory test. Since the gel elastomer composition of Comparative Example 5 contained an ester oil instead of the fatty acid triglyceride (C), the release property of the oil agent was poor, and the emollient effect was not felt even in the sensory test. Furthermore, since the gel elastomer composition of Comparative Example 6 did not contain the fatty acid triglyceride (C) (that is, it contained components other than the styrene-based thermoplastic elastomer mixture (A) and the aliphatic hydrocarbon oil (B). (Because it was not), it was found that the release property of the oil agent was not observed and the effect of the present invention was not exhibited.

Claims (3)

A styrene-based thermoplastic elastomer (A1) having a weight average molecular weight of 100,000 or more and less than 180,000 and composed of a block copolymer of triblock or more including a styrene-based hard segment and an olefin-based soft segment, and a styrene-based thermoplastic elastomer (A1) have a weight average molecular weight. A styrene-based thermoplastic elastomer (A2) composed of a block copolymer of 180,000 or more and 300,000 or less and a triblock or more including a styrene-based hard segment and an olefin-based soft segment can be obtained from (A1) / (A2). With respect to 100 parts by mass of the styrene-based thermoplastic elastomer mixture (A) contained in a mass ratio of 95/5 to 50/50.
500 to 4800 parts by mass of aliphatic hydrocarbon oil (B) having a kinematic viscosity of 5 to 50 mm ² / s at 37.8 ° C. and fatty acid triglyceride (C) 60 to 22 carbon atoms which is liquid at 20 ° C. Containing 1000 parts by mass ,
Further, each of the block copolymers constituting the styrene-based thermoplastic elastomers (A1 and A2) is a gel elastomer in which block components at at least both ends in the molecular chain are block components composed of the styrene-based hard segments. Composition. The fatty acid triglyceride (C) is a saturated fatty acid triglyceride (c1) having 8 to 12 carbon atoms and an unsaturated fatty acid triglyceride (c2) having 14 to 22 carbon atoms, (c1) / (c2) = 95/5 to 5 The gel elastomer composition according to claim 1, which is contained in a mass ratio of 50/50. A cosmetic gel sheet using the gel elastomer composition according to claim 1 or 2 .