JP6199443B2 - Topical skin preparation - Google Patents

Description

  The present invention relates to an external preparation for skin, and more particularly, to an external preparation for skin having an excellent moisturizing effect and good usability.

  An important function required for external preparations for skin, particularly skin care cosmetics, is to maintain the moisture content of the skin, that is, a moisturizing effect. Conventionally, attempts have been made to include various moisturizing agents in the skin external preparation in order to impart a moisturizing effect to the skin external preparation.

  Among them, various acrylic polymers can be cited as leading ones. Specifically, an acrylic polymer having a phosphorylcholine structure in the side chain (see, for example, Patent Document 1, Patent Document 2, and Patent Document 3), and an acrylic polymer having a sugar structure in the side chain (see, for example, Patent Document 4) An acrylic polymer having an amino acid structure in the side chain (for example, see Patent Document 5), an acrylic polymer having a polyethylene structure in the side chain (for example, see Patent Document 6), and the like. However, with these technologies, the moisturizing effect is improved, but due to the characteristics of the polymer, it feels sticky during use or feels squeaky (resistance during application, lack of smoothness). There was a case where a problem arises.

  In order to solve these problems, attempts have been made to include an acrylic polymer having a fluoroalkyl group in an external preparation for skin (see, for example, Patent Document 7, Patent Document 8, and Patent Document 9). In these techniques, a high moisturizing effect and non-stickiness were compatible, but there was almost no effect on removing squeaks.

  Therefore, it has been desired to develop a material capable of giving a high moisturizing effect to the skin external preparation and an excellent feeling of use without stickiness and creaking.

  On the other hand, a copolymer obtained by polymerizing one (meth) acryloyl group and a plurality of acrylic ester monomers having a specific branched structure acyl group and a specific hydrophilic structure acrylic monomer is high in a topical skin preparation. It has not been known to give a moisturizing effect and an excellent feeling of use without stickiness and squeak.

JP 06-157269 A JP 06-157270 A JP 06-157271 A JP-A-2002-193730 No. WO / 032560 JP2003-171257 JP 2004-123726 A JP 2004-123727 A JP 2005-325060 A

  The objective of this invention is providing the skin external preparation which has the outstanding moisturizing effect and the outstanding usability without stickiness and a squeak.

In view of such a situation, the present inventors have intensively studied for an external preparation for skin having an excellent moisturizing effect and an excellent feeling of use without stickiness and creaking. As a result, one (meth) acryloyl group and plural The use of an acrylic ester monomer having an acyl group having a specific branched structure and a copolymer obtained by polymerizing an acrylic monomer having a specific hydrophilic structure has a high moisturizing effect and excellent use without stickiness and creaking. It found out that it gave a feeling and came to this invention. That is, the present invention is as follows.
(1) One or two or more structural units derived from a hydrophobic monomer represented by the following general formula (I) or (II) and one or more structural units derived from a hydrophilic monomer consisting of the following group A The skin external preparation characterized by containing the copolymer which may have other structural units as an essential structural unit.
Formula (I)
(I)
(In the general formula (I), R ¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ² and R ³ may be the same or different, have no ring structure and have a branched carbon number. Represents an acyl group of 6 to 22. P represents a group in which an OH group is eliminated from a trivalent alcohol.
Formula (II)
(II)
(In the general formula (II), R ⁴ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ⁵ , R ⁶ and R ⁷ may be the same or different and do not contain a ring structure and have a branch. Represents an acyl group having 6 to 22 carbon atoms, Q represents a group in which an OH group is eliminated from a tetravalent alcohol.

Group A: polymerizable carboxylic acid, hydrophilic monomer represented by the following general formula (III) general formula (III)
(III)
(In the general formula (III), R ⁸ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ⁹ represents an alkylene group having 2 to 4 carbon atoms which may have a hydroxyl group, and R ¹⁰ represents hydrogen. An atom, an aromatic hydrocarbon group having 6 to 10 carbon atoms, an aliphatic hydrocarbon group having 1 to 14 carbon atoms, or an acyl group having 1 to 12 carbon atoms, and n represents an integer of 6 to 40.)
(2) The hydrophobic monomer represented by the general formula (I) is a hydrophobic monomer represented by the following general formula (IV), and the hydrophobic monomer represented by the general formula (II) is represented by the following general formula The external preparation for skin according to (1), which is a hydrophobic monomer represented by (V).
Formula (IV)
(IV)
(In the general formula (IV), R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ¹² and R ¹³ may be the same or different, have no ring structure, and have a branched carbon number. It represents an acyl group having 10 to 22 or a C 6-9 acyl group having two or more branches that does not contain a ring structure, and S represents a group in which an OH group is eliminated from a trivalent alcohol. )
General formula (V)
(V)
(In the general formula (V), R ¹⁴ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ¹⁵ , R ¹⁶ , and R ¹⁷ may be the same or different and do not include a ring structure and have a branch. Represents an acyl group having 10 to 22 carbon atoms, or an acyl group having 6 to 9 carbon atoms having two or more branches that does not contain a ring structure, and T represents a group in which an OH group is eliminated from a tetravalent alcohol. Represents.)
(3) The skin external preparation according to (1) or (2), wherein the hydrophilic monomer represented by the general formula (III) is a hydrophilic monomer represented by the following general formula (VI).
Formula (VI)
(VI)
(In the general formula (VI), R ¹⁸ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ¹⁹ represents a hydrogen atom, an aromatic hydrocarbon group having 6 to 10 carbon atoms, or an aliphatic group having 1 to 14 carbon atoms. A hydrocarbon group or a C1-C12 acyl group is represented.m represents an integer of 6-40.)
(4) The external preparation for skin according to any one of (1) to (3), wherein the polymerizable carboxylic acid is acrylic acid and / or methacrylic acid.
(5) The external preparation for skin according to any one of (1) to (4), wherein the trihydric alcohol is selected from the group consisting of glycerin, trimethylolpropane, and trimethylolethane.
(6) The tetravalent alcohol is a tetravalent alcohol selected from the group consisting of diglycerin, pentaerythritol, erythritol, D-threitol, and L-threitol (1) to (4) The external preparation for skin according to any one of the above.
(7) The external preparation for skin according to any one of (1) to (6), which is a cosmetic.

  ADVANTAGE OF THE INVENTION According to this invention, the skin external preparation which has the outstanding moisturizing effect and the outstanding usability without stickiness and a squeak is provided.

Hereinafter, the present invention will be described in detail.
<1> A structural unit derived from a hydrophobic monomer constituting a copolymer that is an essential component of the external preparation for skin of the present invention A copolymer that is an essential component of the external preparation for skin of the present invention (hereinafter simply referred to as the copolymer of the present invention) Is a structural unit derived from a hydrophobic monomer represented by the following general formula (I) or general formula (II) (hereinafter sometimes simply referred to as “structural unit I” or “structural unit II”) 1) or 2 or more types thereof as essential constituent units.
Formula (I)
(I)
(In the general formula (I), R ¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ² and R ³ may be the same or different, have no ring structure and have a branched carbon number. Represents an acyl group of 6 to 22. P represents a group in which an OH group is eliminated from a trivalent alcohol.
Formula (II)
(II)
(In the general formula (II), R ⁴ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ⁵ , R ⁶ and R ⁷ may be the same or different and do not contain a ring structure and have a branch. Represents an acyl group having 6 to 22 carbon atoms, Q represents a group in which an OH group is eliminated from a tetravalent alcohol.

Here, examples of the alkyl group represented by R ¹ and R ⁴ include a methyl group, an ethyl group, a propyl group, an isopropyl group, and a cyclopropyl group. In the present invention, R1 is preferably a hydrogen atom or a methyl group.

^{Further, R 2, R 3, R} 5, does not contain a ring structure represented by R 6, ^{R 7,} the acyl group of 6 to 22 carbon atoms and having a branch, 2-methyl pentanoyl group, 3-methyl Pentanoyl group, 4-methylpentanoyl group, 2-ethylbutanoyl group, 2-ethylbutanoyl group, 2,2-dimethylbutanoyl group, 3,3-dimethylbutanoyl group, 2-methylhexanoyl group, 4-methylhexanoyl group, 5-methylhexanoyl group, 2,2-dimethylpentanoyl group, 4,4-dimethylpentanoyl group, 2-methylheptanoyl group, 2-ethylhexyl group, 2-propylpentanoyl group 2,2-dimethylhexanoyl group, 2,2,3-trimethylpentanoyl group, 2-methyloctanoyl group, 3,3,5-trimethylhexanoyl group, 2-methylnona Yl group, 4-methylnonanoyl group, 8-methylnonanoyl group, 4-ethyloctanoyl group, 2-ethyloctanoyl group, 2-butylhexanoyl group, 2-tert-butylhexanoyl group, 2,2-diethylhexanoyl group Group, 2,2-dimethyloctanoyl group, 3,7-dimethyloctanoyl group, neodecanoyl group, 7-methyldecanoyl group), 2-methyl-2-ethyloctanoyl group, 2-methylundecanoyl group, 10-methylundecanoyl group, 2,2 dimethyldecanoyl group, 2-ethyldecanoyl group, 2-butyloctanoyl group, diethyloctanoyl group, 2-tert-butyl-2,2,4-trimethylpentanoyl Group, 10-methyldodecanoyl group, 3-methyldodecanoyl group, 4-methyldodecanoyl group, 11-methyldodecanoyl group, 10-ethylundecanoyl group, 12-methyltridecanoyl group, 2-butyldecanoyl group, 2-hexyloctanoyl group, 2-butyl-2-ethyloctanoyl group, 12-methyltetradecanoyl group, 14 -Methylpentadecanoyl group, 2-butyldodecanoyl group, 2-hexyldecanoyl group, 16-methylheptadecanoyl group, 2,2-dimethylhexanoyl group, 2-butylhexadecanoyl group, 2-hexyldodeca Noyl group, 2,4,10,14-tetramethylpentanoyl group, 18-methylnonadecanoyl group, 3,7,11,15-tetra-methylhexadecanoyl group, 19-methyleicosanoyl group, etc. It can be illustrated.

Among the hydrophobic monomers represented by the general formula (I) or (II), a hydrophobic monomer represented by the following general formula (IV) or (V) is particularly preferable.
Formula (IV)
(IV)
(In the general formula (IV), R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ¹² and R ¹³ may be the same or different, have no ring structure, and have a branched carbon number. It represents an acyl group having 10 to 22 or a C 6-9 acyl group having two or more branches that does not contain a ring structure, and S represents a group in which an OH group is eliminated from a trivalent alcohol. )
General formula (V)
(V)
(In the general formula (V), R ¹⁴ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ¹⁵ , R ¹⁶ , and R ¹⁷ may be the same or different and do not include a ring structure and have a branch. Represents an acyl group having 10 to 22 carbon atoms, or an acyl group having 6 to 9 carbon atoms having two or more branches that does not contain a ring structure, and T represents a group in which an OH group is eliminated from a tetravalent alcohol. Represents.)

Here, examples of the alkyl group represented by R ¹¹ and R ¹⁴ include a methyl group, an ethyl group, a propyl group, an isopropyl group, and a cyclopropyl group. In the present invention, R ⁴ and R ⁷ are preferably a hydrogen atom or a methyl group.

Examples of the branched acyl group having 10 to 22 carbon atoms which does not include a ring structure and is represented by R ¹² , R ¹³ , R ¹⁵ , R ¹⁶ and R ¹⁷ include a 2-methylnonanoyl group, a 4-methylnonanoyl group, 8 -Methylnonanoyl group, 4-ethyloctanoyl group, 2-ethyloctanoyl group, 2-butylhexanoyl group, 2-tert-butylhexanoyl group, 2,2-diethylhexanoyl group), 2,2-dimethylocta Noyl group, 3,7-dimethyloctanoyl group, neodecanoyl group), 7-methyldecanoyl group, 2-methyl-2-ethyloctanoyl group, 2-methylundecanoyl group, 10-methylundecanoyl group, 2,2 dimethyldecanoyl group, 2-ethyldecanoyl group, 2-butyloctanoyl group, diethyloctanoyl group, 2-tert-butyl-2,2 4-trimethylpentanoyl group, 10-methyldodecanoyl group, 3-methyldodecanoyl group, 4-methyldodecanoyl group, 11-methyldodecanoyl group, 10-ethylundecanoyl group, 12-methyltridecanoyl group 2-butyldecanoyl group, 2-hexyloctanoyl group, 2-butyl-2-ethyloctanoyl group, 12-methyltetradecanoyl group, 14-methylpentadecanoyl group, 2-butyldodecanoyl group, 2 -Hexyldecanoyl group, 16-methylheptadecanoyl group, 2,2-dimethylhexanoyl group, 2-butylhexadecanoyl group, 2-hexyldecanoyl group, 2,4,10,14-tetramethylpentanoyl Group, 18-methylnonadecanoyl group, 3,7,11,15-tetra-methylhexadecanoyl group, 19-me Examples include a tileicosanoyl group.

In addition, as the acyl group having 6 to 9 carbon atoms having 2 or more branches and not containing a ring structure, represented by R ¹² , R ¹³ , R ¹⁵ , R ¹⁶ , R ¹⁷ , 2,2-dimethyl Butanoyl group, 3,3-dimethylbutanoyl group, 2,2-dimethylpentanoyl group, 4,4-dimethylpentanoyl group, 2,2-dimethylhexanoyl group, 2,2,3-trimethylpentanoyl group 3,5,5-trimethylhexanoyl group and the like.

  The group derived from the trihydric alcohol represented by P and S is not particularly limited as long as the OH group is released from the trihydric alcohol, but from the group consisting of glycerin, trimethylolpropane, and trimethylolethane. A group in which an OH group is eliminated from the selected trihydric alcohol can be suitably exemplified.

  The group derived from tetrahydric alcohol represented by Q and T is not particularly limited as long as the OH group is removed from the tetrahydric alcohol, but diglycerin, pentaerythritol, erythritol, D-tray. A group in which an OH group is eliminated from a tetrahydric alcohol selected from the group consisting of Tol and L-Treitol can be preferably exemplified.

  The proportion of the structural unit I and / or the structural unit II in the total structural unit in the copolymer of the present invention is preferably 1 to 40% by mass, more preferably 5 to 35% by mass. Below the lower limit, the feeling of use of the external preparation for skin containing the resulting copolymer may be lowered, which is not preferable. On the other hand, if it exceeds the upper limit, the solubility of the copolymer obtained in the external preparation for skin, particularly in water, is markedly lowered, and it may be difficult to prepare the external preparation for skin.

The hydrophobic monomer represented by the general formula (I) constituting the copolymer of the present invention can be synthesized, for example, by the following method.
a) Ketalize the trihydric alcohol. As a specific synthesis method, for example, the method described in Production Example 1 of JP-A-2009-136749 can be exemplified.
b) A ketal (meth) acrylate ester was synthesized by transesterification of the ketalized trihydric alcohol synthesized in a with a (meth) acrylic acid alkyl ester, and the resulting ketal (meth) acrylic ester was synthesized. Carboxylation reaction is performed to synthesize mono (meth) acrylic acid ester of trihydric alcohol. As a specific synthesis method, for example, the method described in Example 1 of JP-A-2004-18389 can be exemplified.
c) Hydrophobicity represented by the general formula (I) by reacting the mono (meth) acrylic acid ester of the trihydric alcohol obtained in b with a carboxylic acid having a predetermined branched structure or an anhydride or chloride thereof. Monomer is obtained.

  In addition, since the ketalized trihydric alcohol also has a commercial item, it is also possible to obtain the ester of the trihydric alcohol of the present invention by using the commercially available product and the above steps b) and c). Such commercially available products include (S)-(+)-2,2-dimethyl-1,3-dioxalane-4-methanol, (R)-(+)-2,2-dimethyl-1,3- Examples include dioxalane-4-methanol (both manufactured by Tokyo Chemical Industry Co., Ltd.).

  Further, since there are commercially available products of mono (meth) acrylic acid esters of trihydric alcohols, it is also possible to obtain the esters of the trihydric alcohols of the present invention by using the commercially available products and the above step c). An example of such a commercially available product is “Blemmer GLM” (glycerin monomethacrylate manufactured by Nippon Oil & Fats Co., Ltd.).

Moreover, the hydrophobic monomer represented by the general formula (II) constituting the copolymer of the present invention can be synthesized, for example, by the following method. The specific method of steps a) and b) is described in US Pat. No. 4,405,798, Anne Buyle Padias, HK Hall Jr. Macromolecules 15, 217 (1982) and the like.
a) Esterify and mask the three OH groups of the tetrahydric alcohol.
b) The compound synthesized in a is reacted with (meth) acrylic acid or (meth) acrylic anhydride or (meth) acrylic chloride. The obtained ester is further hydrolyzed to synthesize a mono (meth) acrylic acid ester of a tetrahydric alcohol.
c) Hydrophobic property represented by the general formula (II) by reacting the mono (meth) acrylic acid ester of the tetrahydric alcohol obtained in b with a carboxylic acid having a predetermined branched structure or an anhydride or chloride thereof. Monomer is obtained.

Hereinafter, production examples of hydrophobic monomers represented by the general formulas (I) and (II) will be shown.
<Production Example 1> Synthesis of glycerin monoacrylate In a 3 L four-necked flask, R)-(+)-2,2-dimethyl-1,3-dioxalane-4-methanol (manufactured by Tokyo Chemical Industry Co., Ltd.) 79 0.5 g, methyl acrylate 258.0 g, and tetramethoxy titanium 3.7 g were charged. Then, the reaction liquid was stirred, and a transesterification reaction was performed at 105 to 110 ° C. for 2.5 hours while introducing nitrogen gas into the liquid. After completion of the reaction, ketal acrylate 1 (intermediate 1) was obtained by fractionation by distillation under reduced pressure.

  In a 3 L four-necked flask, 90.2 g of water, 28.4 ml of cation exchange resin RCP160M (manufactured by Mitsubishi Chemical), 94.2 g of Intermediate 1 were charged. Then, the reaction solution was stirred, and a ketal deketone reaction was carried out at 24 ° C. for 27 hours while introducing nitrogen gas into the solution. After completion of the reaction, the cation exchange resin was filtered off from the reaction solution, and the filtered reaction solution was washed 6 times with 100 ml of hexane to remove unreacted raw materials, and then 200 ml of ethyl acetate was added to the aqueous layer to obtain a product. Extracted. Then, ethyl acetate and water were distilled off from this ethyl acetate extract under reduced pressure (800 Pa) at 40 ° C. or less to obtain glyceryl monoacrylate.

<Production Example 2> Synthesis of trimethylolpropane monoacrylate Step (1): 145.7 g of trimethylolpropane, 300 ml of acetone, in an eggplant-shaped flask equipped with a calcium tube, a condenser tube and a Dean-Stark trap. 3 g of p-toluenesulfonic acid monohydrate and 300 mL of petroleum ether were added and heated to reflux in an oil bath set at 50 ° C. After 12 hours, after confirming that water was no longer generated, the reaction mixture was cooled to room temperature. Next, 3 g of sodium acetate was added and the mixture was further stirred for 30 minutes, and then petroleum ether and acetone were distilled off by an evaporator. The obtained crude product was distilled under reduced pressure to obtain ketalized trimethylolpropane (intermediate 2).

  Step (2): 104.8 g of Intermediate 2 obtained in Step (1), 258.0 g of methyl acrylate, and 3.7 g of tetramethoxy titanium were charged into a 3 L four-necked flask. Then, the reaction liquid was stirred, and a transesterification reaction was performed at 105 to 110 ° C. for 2.5 hours while introducing nitrogen gas into the liquid. After completion of the reaction, ketalized trimethylolpropane acrylate ester (intermediate 3) was obtained by fractionation by distillation under reduced pressure.

  Step (3): A 3L 4-neck flask was charged with 90.2 g of water, 28.4 ml of cation exchange resin RCP160M (manufactured by Mitsubishi Chemical), and 115.3 g of Intermediate 3 obtained in Step (2). Then, the reaction solution was stirred, and a ketal deketone reaction was carried out at 24 ° C. for 27 hours while introducing nitrogen gas into the solution. After completion of the reaction, the cation exchange resin was filtered off from the reaction solution, and the filtered reaction solution was washed 6 times with 100 ml of hexane to remove unreacted raw materials, and then 200 ml of ethyl acetate was added to the aqueous layer to obtain a product. Extracted. Then, ethyl acetate and water were distilled off from this ethyl acetate extract under reduced pressure (800 Pa) at 40 ° C. or lower to obtain trimethylolpropane monoacrylate.

<Production Example 3> Synthesis of trimethylolpropane monomethacrylate Trimethylolpropane, methyl acrylate (acrylate) in Production Example 2, the amount of intermediates obtained in step (1), and the intermediates obtained in step (2) Trimethylolpropane monomethacrylate was synthesized in the same manner as in Production Example 2 except that the amount was changed as shown in Table 1. Table 1 shows the trivalent alcohol and its charge, the intermediate obtained in step (1) and its charge, the intermediate obtained in process (2) and its charge.

<Production Example 4> Synthesis of pentaerythritol monoacrylate Step (A) In a 3 L four-necked flask equipped with a stirrer and a condenser, 34.0 g of pentaerythritol, triethyl orthoformate (manufactured by Sigma-Aldrich), 37.0 g, phthalate 750 ml of dioctyl acid (Tokyo Chemical Industry Co., Ltd.) and 0.1 g of paratoluenesulfonic acid (Tokyo Chemical Industry Co., Ltd.) were taken and mixed. Then, it heated at 140 degreeC and reacted for 2.5 hours. After completion of the reaction, purification was performed by distillation under reduced pressure to obtain Intermediate 6.

  Step (B) In a reaction vessel equipped with a stirrer, 29.2 g of Intermediate 6 obtained in Step (A) and 50.0 g of triethylamine were dissolved in 300 ml of tetrahydrofuran. While the resulting solution was ice-cooled and stirred, a solution prepared by dissolving 18.1 g of acrylic acid chloride Tokyo Chemical Industry Co., Ltd. in 100 ml of tetrahydrofuran was added dropwise over 2 hours. After completion of the dropwise addition, the produced white precipitate was filtered, and tetrahydrofuran and triethylamine were removed from the filtrate using a rotary evaporator to obtain Intermediate 7.

Step (C) In a vessel equipped with a stirrer and a cooler, 40.0 g of Intermediate 7 obtained in Step (B) was stirred and dissolved in 300 ml of water. Thereafter, the reaction was carried out at 70 ° C. for 6 hours while continuing the stirring, and then water was removed by evaporation, followed by drying to obtain pentaerythritol monoacrylate.

<Production Examples 5 to 7> Synthesis of tetrahydric alcohol mono (meth) acrylate Pentaerythritol in the step (A) of Production Example 4, the charge amount of the intermediate obtained in the step (A) in the step (B), and acrylic acid chloride The same operation as in Production Example 4 was carried out except that the amount of the intermediate obtained in step (B) in step (C) was changed as shown in Table 2, and a mono (meth) acrylic acid ester of a tetrahydric alcohol. Was synthesized. Table 2 shows the tetravalent alcohol and its charge, the intermediate obtained in step (A) and its charge, the intermediate obtained in step (B) and its charge, and the resulting mono (meth) acrylate. Show.

* 1) Tokyo Chemical Industry Co., Ltd. * 2) Tokyo Chemical Industry Co., Ltd.

<Production Example 8> Production example 1 of a hydrophobic monomer represented by formula (I)
In a reaction vessel equipped with a stirrer and a condenser tube, 28.4 g of 16-methylheptadecanoic acid (manufactured by Sigma-Aldrich), 35.7 g of thionyl chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) and 200 ml of benzene were stirred and mixed. . While continuing stirring, refluxing was performed for 4 hours, and then purification by vacuum distillation was performed to obtain 16-methylheptadecanoic acid chloride.

In a reaction vessel equipped with a stirrer, 16.0 g of glyceryl monomethacrylate (“Blenmer GLM” manufactured by NOF Corporation) and 30.0 g of triethylamine were dissolved in 300 ml of tetrahydrofuran. While the resulting solution was ice-cooled and stirred, a solution prepared by dissolving 60.6 g of 16-methylheptadecanoic acid chloride obtained above in 100 ml of tetrahydrofuran was added dropwise over 2 hours. After completion of the dropwise addition, the produced white precipitate was filtered, and tetrahydrofuran and triethylamine were removed from the filtrate using a rotary evaporator to obtain a product. From the NMR measurement, it was confirmed that the obtained compound was a hydrophobic monomer (hydrophobic monomer 1) derived from the essential structural unit of the copolymer of the present invention represented by the general formula (VII).
Formula (VII)
(VII)

<Production Example 9> Production example 1 of a hydrophobic monomer represented by formula (II)
In a reaction vessel equipped with a stirrer and a condenser tube, 28.4 g of 16-methylheptadecanoic acid (manufactured by Sigma-Aldrich), 35.7 g of thionyl chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) and 200 ml of benzene were stirred and mixed. . While continuing stirring, refluxing was performed for 4 hours, and then purification by vacuum distillation was performed to obtain 16-methylheptadecanoic acid chloride.

In a reaction vessel equipped with a stirrer, 19.0 g of pentaerythritol (the compound obtained in Production Example 4) and 30.0 g of triethylamine were dissolved in 500 ml of tetrahydrofuran. While the resulting solution was ice-cooled and stirred, a solution prepared by dissolving 90.9 g of 16-methylheptadecanoic acid chloride obtained above in 200 ml of tetrahydrofuran was added dropwise over 2 hours. After completion of the dropwise addition, the produced white precipitate was filtered, and tetrahydrofuran and triethylamine were removed from the filtrate using a rotary evaporator to obtain a product. From the NMR measurement, it was confirmed that the obtained compound was a hydrophobic monomer (hydrophobic monomer 2) for deriving an essential structural unit of the copolymer of the present invention represented by the general formula (VIII).
Formula (VIII)
(VIII)

<Production example 10> Production example 2 of a hydrophobic monomer represented by formula (I)
In a reaction vessel equipped with a stirrer and a condenser tube, 32.7 g of 19-methyleicosanoic acid (manufactured by Sigma-Aldrich), 35.7 g of thionyl chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) and 200 ml of benzene were stirred and mixed. . Refluxing was performed for 4 hours while continuing stirring, and then purification by vacuum distillation was performed to obtain 19-methyleicosanoic acid chloride.

In a reaction vessel equipped with a stirrer, 18.8 g of trimethylolethane monomethacrylate (the compound obtained in Production Example 3) and 30.0 g of triethylamine were dissolved in 300 ml of tetrahydrofuran. While the resulting solution was ice-cooled and stirred, a solution prepared by dissolving 69.0 g of 19-methyleicosanoic acid chloride obtained above in 100 ml of tetrahydrofuran was added dropwise over 2 hours. After completion of the dropwise addition, the produced white precipitate was filtered, and tetrahydrofuran and triethylamine were removed from the filtrate using a rotary evaporator to obtain a product. From the NMR measurement, it was confirmed that the obtained compound was a hydrophobic monomer (hydrophobic monomer 3) derived from the essential structural unit of the copolymer of the present invention represented by the general formula (IX).
Formula (IX)
(IX)

<Production Example 11> Production Example 3 of Hydrophobic Monomer Represented by Formula (I) Part 3
In a reaction vessel equipped with a stirrer and a cooling tube, 17.2 g of 2,2-dimethyloctanoic acid (manufactured by Sigma-Aldrich), 35.7 g of thionyl chloride (manufactured by Tokyo Chemical Industry Co., Ltd.), and 200 ml of benzene were stirred and mixed. did. While continuing stirring, refluxing was performed for 4 hours, and then purification by vacuum distillation was performed to obtain 2,2-dimethyloctanoic acid chloride.

In a reaction vessel equipped with a stirrer, 18.8 g of trimethylolpropane monoacrylate (the compound obtained in Production Example 2) and 30.0 g of triethylamine were dissolved in 300 ml of tetrahydrofuran. While the resulting solution was ice-cooled and stirred, a solution prepared by dissolving 38.2 g of 2,2-dimethyloctanoic acid chloride obtained above in 100 ml of tetrahydrofuran was added dropwise over 2 hours. After completion of the dropwise addition, the produced white precipitate was filtered, and tetrahydrofuran and triethylamine were removed from the filtrate using a rotary evaporator to obtain a product. By NMR measurement, it was confirmed that the obtained compound was a hydrophobic monomer (hydrophobic monomer 4) derived from the essential structural unit of the copolymer of the present invention represented by the general formula (X).
Formula (X)
(X)

<Production example 12> Production example 4 of a hydrophobic monomer represented by the general formula (I)
In a reaction vessel equipped with a stirrer, 29.2 of glyceryl monoacrylate (the compound obtained in Production Example 1) and 50.0 g of triethylamine were dissolved in 500 ml of tetrahydrofuran. While the resulting solution was ice-cooled and stirred, a solution prepared by dissolving 65.1 g of 2-ethylhexanoic acid chloride (manufactured by Sigma-Aldrich) in 100 ml of tetrahydrofuran was added dropwise over 2 hours. After completion of the dropwise addition, the produced white precipitate was filtered, and tetrahydrofuran and triethylamine were removed from the filtrate using a rotary evaporator to obtain a product. By NMR measurement, it was confirmed that the obtained compound was a hydrophobic monomer (hydrophobic monomer 5) derived from the essential structural unit of the copolymer of the present invention represented by the general formula (XI).
Formula (XI)
(XI)

<Production example 13> Production example 2 of a hydrophobic monomer represented by formula (II)
In a reaction vessel equipped with a stirrer, 40.8 g of pentaerythritol monomethacrylate (the compound obtained in Production Example 5) and 50.0 g of triethylamine were dissolved in 500 ml of tetrahydrofuran. While the resulting solution was ice-cooled and stirred, a solution prepared by dissolving 106.0 g of 3,5,5-trimethylhexanoic acid chloride (manufactured by Sigma-Aldrich) in 200 ml of tetrahydrofuran was added dropwise over 2 hours. After completion of the dropwise addition, the produced white precipitate was filtered, and tetrahydrofuran and triethylamine were removed from the filtrate using a rotary evaporator to obtain a product. From the NMR measurement, it was confirmed that the obtained compound was a hydrophobic monomer (hydrophobic monomer 6) derived from the essential structural unit of the copolymer of the present invention represented by the general formula (XII).
Formula (XII)
(XII)

<Production example 14> Production example 3 of a hydrophobic monomer represented by formula (II)
In a reaction vessel equipped with a stirrer and a condenser, 22.8 g of 2-butyl-2-ethyloctanoic acid (manufactured by Sigma-Aldrich), 35.7 g of thionyl chloride (manufactured by Tokyo Chemical Industry Co., Ltd.), and 200 ml of benzene are taken. Stir and mix. Refluxing was performed for 4 hours while continuing stirring, and then purification by vacuum distillation was performed to obtain 2-butyl-2-ethyloctanoic acid chloride.

In a reaction vessel equipped with a stirrer, 22.0 g of diglycerin monoacrylate (the compound obtained in Production Example 6) and 30.0 g of triethylamine were dissolved in 300 ml of tetrahydrofuran. While the resulting solution was ice-cooled and stirred, a solution prepared by dissolving 74.0 g of 2-butyl-2-ethyloctanoic acid chloride obtained above in 200 ml of tetrahydrofuran was added dropwise over 2 hours. After completion of the dropwise addition, the produced white precipitate was filtered, and tetrahydrofuran and triethylamine were removed from the filtrate using a rotary evaporator to obtain a product. From the NMR measurement, it was confirmed that the obtained compound was a hydrophobic monomer (hydrophobic monomer 7) derived from the essential structural unit of the copolymer of the present invention represented by the general formula (XIII).
Formula (XIII)
(XIII)

<Production Example 15> Production Example 4 of Hydrophobic Monomer Represented by General Formula (II)
In a reaction vessel equipped with a stirrer and a condenser tube, 32.7 g of 19-methyleicosanoic acid (manufactured by Sigma-Aldrich), 35.7 g of thionyl chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) and 200 ml of benzene were stirred and mixed. . Refluxing was performed for 4 hours while continuing stirring, and then purification by vacuum distillation was performed to obtain 19-methyleicosanoic acid chloride.

In a reaction vessel equipped with a stirrer, 19.0 g of erythritol monomethacrylate (the compound obtained in Production Example 7) and 50.0 g of triethylamine were dissolved in 300 ml of tetrahydrofuran. While the resulting solution was ice-cooled and stirred, a solution prepared by dissolving 103.5 g of 19-methyleicosanoic acid chloride obtained above in 200 ml of tetrahydrofuran was added dropwise over 2 hours. After completion of the dropwise addition, the produced white precipitate was filtered, and tetrahydrofuran and triethylamine were removed from the filtrate using a rotary evaporator to obtain a product. By NMR measurement, it was confirmed that the obtained compound was a hydrophobic monomer (hydrophobic monomer 8) derived from the essential structural unit of the copolymer of the present invention represented by the general formula (XIV).
Formula (XIV)
(XIV)

<2> A structural unit derived from a hydrophilic monomer constituting the copolymer of the present invention.
The copolymer of the present invention has one or more structural units derived from a hydrophilic monomer selected from the group consisting of a polymerizable carboxylic acid, a salt thereof or a monomer represented by the following general formula (III) as essential structural units. contains. (Hereinafter, the structural unit derived from the hydrophilic monomer selected from the group consisting of the monomer represented by the general formula (III) may be simply referred to as the structural unit III.)
Formula (III)
(III)
(In the general formula (III), R ⁸ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ⁹ represents an alkylene group having 2 to 4 carbon atoms which may have a hydroxyl group, and R ¹⁰ represents hydrogen. An atom, an aromatic hydrocarbon group having 6 to 10 carbon atoms, an aliphatic hydrocarbon group having 1 to 14 carbon atoms, or an acyl group having 1 to 12 carbon atoms, and n represents an integer of 6 to 40.)

  Specific examples of the polymerizable carboxylic acid or its salt include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, fumaric acid and its sodium salt, potassium salt, ammonium salt, amine salt and the like. Among these, acrylic acid, methacrylic acid and salts thereof are particularly preferable because of high polymerizability. When a structural unit derived from a polymerizable carboxylic acid salt is introduced into the water-soluble copolymer of the present invention, the polymerizable carboxylic acid may be converted into a salt in advance, and a polymerization reaction may be performed. A structural unit derived from a carboxylic acid may be derived into a copolymer and then neutralized with a base to form a salt.

Examples of the alkyl group represented by R8 in the general formula (III) include a methyl group, an ethyl group, a propyl group, a 1-methylethyl group, and a cyclopropyl group. In the present invention, R ⁸ is preferably a hydrogen atom or a methyl group.

Examples of the alkylene group represented by R ⁹ include an ethylene group, a propylene group, an isopropylene group, a 2-hydroxypropylene group, a 1-hydroxy-2-methylethylene group, and a 2-hydroxy-1-methylethylene group. Of these, ethylene group or propylene group is preferable, and ethylene group is more preferable.

In addition, among the groups represented by R ¹⁰ , examples of the aromatic group having 6 to 10 carbon atoms include a phenyl group, a benzyl group, a methylphenyl group, and an ethylphenyl group; an aliphatic group having 1 to 14 carbon atoms Preferred examples of the hydrocarbon group include a methyl group, an ethyl group, a butyl group, a tertiary butyl group, a hexyl group, a cyclohexyl group, an octyl group, a 2-ethylhexyl group, and a lauryl group; Preferable examples of the ˜12 acyl group include a formyl group, an acetyl group, a propionyl group, a butyryl group, an isobutyryl group, a valeryl group, and a lauroyl group. Among these, the group represented by R ⁵ is preferably an aliphatic hydrocarbon group having 1 to 14 carbon atoms, and more preferably an alkyl group having 1 to 12 carbon atoms.

  Furthermore, it is important that n in the general formula (III) is in a numerical range of 6 to 40. In the present invention, by introducing the structural unit II in which n is in the above range into the copolymer, a component of the external preparation for skin, particularly a copolymer having good solubility in water, can be obtained, and the copolymer can be easily used as an external preparation for skin. It can be contained, and an excellent skin moisturizing effect and feeling of use can be imparted to the external preparation for skin. When n is less than 6, the solubility of the resulting copolymer in the external preparation for skin, particularly water, may be significantly lowered, which is not preferable. On the other hand, if n is larger than 40, the stickiness and squeak of the external preparation for skin may be amplified, which is not preferable.

Among the monomers represented by the general formula (III), specific examples of the monomer in which R ⁹ is a propylene group include polypropylene glycol (9) monoacrylate, polypropylene glycol (13) monoacrylate, and polypropylene glycol (9) mono Examples include methacrylate and polypropylene glycol (13) monomethacrylate. The number in parentheses represents n. Many of these polymers are commercially available. Specific examples of these commercially available products include “Blemmer” AP-400, AP-550, AP-800, PP-500, PP-800 (all manufactured by NOF Corporation) and the like. A specific example of the monomer in which R ⁴ is an ethylene group will be described later.

Among the structural units derived from the hydrophilic monomer represented by the general formula (III), a structural unit derived from the hydrophilic monomer represented by the following general formula (VI) is particularly preferable.
Formula (VI)
(VI)
(In General Formula (VI), R ¹⁸ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ¹⁹ represents a hydrogen atom, an aromatic hydrocarbon group having 6 to 10 carbon atoms, or an aliphatic group having 1 to 14 carbon atoms. A hydrocarbon group or a C1-C12 acyl group is represented.m represents an integer of 6-40.)

  Specific examples of the monomer represented by the general formula (III) include polyethylene glycol (10) monoacrylate, polyethylene glycol (8) monomethacrylate, polyethylene glycol (23) monoacrylate, and polyethylene glycol (23). Monomethacrylate, methoxypolyethylene glycol (9) acrylate, methoxypolyethylene glycol (9) methacrylate, methoxypolyethylene glycol (23) methacrylate, oleyloxypolyethylene glycol (18) methacrylate, lauroxypolyethylene glycol (18) acrylate, lauryloxypolyethylene glycol (10) Methacrylate, stearoxy polyethylene glycol (30) monomethacrylate and the like. The number in parentheses indicates the value of m.

  In addition, as described in the general formula (III), similarly in the general formula (VI), a component having a good solubility in water, particularly a component for external preparation of the skin, and a skin external preparation are obtained. It is important that m is in the numerical range of 6 to 40 in order to impart an excellent moisturizing effect and usability.

  These hydrophilic monomers can be obtained in high yield by an esterification reaction of the corresponding polyethylene glycol, polyethylene glycol monoether, polyethylene glycol monoester and acrylic acid or methacrylic acid chloride or anhydride. Moreover, since there are already many commercial products, it is also possible to use such commercial products. Specific examples of such commercially available products include the trade names Blemmer, AE-400, PE-350, AME-400, PME-400, PME-1000, ALE-800, PSE-1300, etc. Etc.).

  The structural unit derived from the hydrophilic monomer contained in the copolymer of the present invention may be only one type, but may contain two or more types of structural units in combination as long as the above-mentioned conditions are satisfied.

  In the copolymer of the present invention, the proportion of the structural units derived from the hydrophilic monomer to the total structural units is preferably 30 to 95% by mass, more preferably 40 to 90% by mass. Below the lower limit, the solubility of the obtained copolymer in the external preparation for skin, particularly water, may be significantly lowered, which is not preferable. On the other hand, if it exceeds the upper limit, the stickiness and squeakiness of the external preparation containing the copolymer obtained may be amplified, which is not preferable.

<3> Other optional structural units that can be included in the copolymer of the present invention The copolymer of the present invention is composed of one or more essential structural units selected from the structural unit I and the structural unit II, and a hydrophilic monomer. In addition to the essential structural unit derived, a unit derived from a monomer usually used in a copolymer can be contained as an arbitrary structural unit within a range not impairing the effects of the invention. Examples of such optional structural units include acrylic acid amide, methacrylic acid amide, acrylic acid monoalkylamide, (meth) acrylic acid amide such as methacrylic acid monoalkylamide, methyl (meth) acrylate, ethyl (meth) acrylate, (Meth) acrylic acid-n-butyl, (meth) acrylic acid isobutyl, (meth) acrylic acid-tert-butyl, (meth) acrylic acid n-octyl, (meth) acrylic acid-2-ethylhexyl, methacrylate n-dodecyl methacrylate (Meth) acrylic acid stearyl, (meth) acrylic acid isostearyl (meth) acrylic acid alkyl ester, (meth) acrylic acid cyclic alkyl ester such as cyclohexyl (meth) acrylic acid, 2-hydroxyethyl (meth) Acrylate, 2-hydroxypropyl (meth) acrylate, 4 -(Meth) acrylic acid hydroxyalkyl esters such as hydroxybutyl (meth) acrylate, (meth) acrylic acid aryl esters such as benzyl (meth) acrylate, methoxymethyl (meth) acrylate, methoxyethyl (meth) acrylate, etc. Examples thereof include structural units derived from monomers such as (meth) acrylic acid alkoxyalkyl esters, vinyl acetate, vinylpyrrolidone, styrene, α-methylstyrene, acrylonitrile and the like. Most of these monomers are commercially available.

<4> Copolymer of the Present Invention The copolymer of the present invention comprises an essential structural unit derived from the structural unit I and / or the structural unit II and a hydrophilic monomer, and an optional structural unit as necessary in its skeleton. Is a copolymer contained in

  Further, the copolymer of the present invention is usually a random copolymer in which structural units are randomly bonded, but may be a block copolymer or a graft copolymer.

  The method for producing the copolymer of the present invention is not particularly limited. For example, the copolymer can be obtained by a method in which monomers for deriving each structural unit are mixed in a solvent and a polymerization reaction is carried out according to a method usually used in the polymerization of acrylic monomers.

  The copolymer of the present invention is preferably water-soluble because it can be easily blended into a skin external preparation. The water-soluble copolymer here is defined as a copolymer having a transmittance of 90% or more of a 20% by mass aqueous solution of the copolymer at 25 ° C. In order to obtain such a polymer, among the above polymerization methods, a polymerization method in which the monomer mixture is radically polymerized in a mixed solvent of an aqueous solution and an aqueous solvent mixed with water at an arbitrary ratio at 25 ° C. is particularly preferable. . Moreover, since the amount of residual monomer after the polymerization reaction is small, a polymerization method using a buffer solution instead of water is more preferable. The aqueous solution having a buffering action used in this method is not particularly limited as long as it is a commonly used buffer solution. Specifically, potassium chloride-hydrochloric acid solution, potassium hydrogen phthalate-hydrochloric acid solution, dihydrogen phosphate Examples thereof include potassium-disodium hydrogen phosphate solution, potassium hydrogen citrate-citric acid solution, and sodium carbonate-sodium hydrogen carbonate solution. Alternatively, an aqueous solution of salts, acids, or bases that forms a buffer solution with the ions of the initiator may be used to form a buffer solution when the initiator is added. Furthermore, as an aqueous solvent mixed with water at an arbitrary ratio at 25 ° C. used in this method, specifically, alcohols having 1 to 3 carbon atoms such as methyl alcohol, ethyl alcohol, n-propyl alcohol and isopropyl alcohol, acetone Examples thereof include ketones such as methyl ethyl ketone, diols such as ethylene glycol, polyethylene glycol, propylene glycol and 1,3 butylene glycol, ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether, and tetrahydrofuran. Among these aqueous solvents, alcohols having 1 to 3 carbon atoms such as methyl alcohol, ethyl alcohol, n-propyl alcohol, and isopropyl alcohol are particularly preferable because the polymerization reaction easily proceeds.

Hereinafter, production examples of the copolymer of the present invention will be shown.
<Production Example 16>
In a flask equipped with a nitrogen inlet tube, a condenser and a stirrer, 30.0 g of hydrophobic monomer 1 (Production Example 8), methoxypolyethylene glycol (23) methacrylate (manufactured by NOF Corporation, trade name “Blemmer PME-1000” ] 90.0 g, isopropyl alcohol 300 ml, phosphate buffer solution (pH 6.8) (manufactured by Nacalai Tesque Co., Ltd.) 300 ml were taken and mixed with stirring. While stirring was continued, nitrogen gas substitution was performed for 1 hour. A solution prepared by dissolving 2.0 g of ammonium persulfate in 20 ml of water was added thereto, and the reaction was continued at 65 ° C. for 16 hours while continuing stirring. After completion of the reaction, the pH was adjusted to 7.0 using an aqueous sodium hydroxide solution, and isopropyl alcohol was removed using a rotary evaporator to obtain an aqueous solution of copolymer 1 of the present invention.

<Production Example 17>
In a flask equipped with a nitrogen inlet tube, a condenser and a stirrer, 18.0 g of hydrophobic monomer 2 (Production Example 9), methoxypolyethylene glycol (23) methacrylate (manufactured by NOF Corporation, trade name “Blemmer PME-1000” ] 90.0 g, 2-hydroxyethyl methacrylate (Tokyo Kasei Kogyo Co., Ltd.) 12.0 g, isopropyl alcohol 300 ml, phosphate buffer solution (pH 6.8) (Nacalai Tesque Co., Ltd.) 300 ml and stirred Mixed. While stirring was continued, nitrogen gas substitution was performed for 1 hour. A solution prepared by dissolving 2.0 g of ammonium persulfate in 20 ml of water was added thereto, and the reaction was performed at 60 ° C. for 18 hours while continuing stirring. After completion of the reaction, the pH was adjusted to 7.0 using an aqueous sodium hydroxide solution, and isopropyl alcohol was removed using a rotary evaporator to obtain an aqueous solution of copolymer 2 of the present invention.

<Production Example 18>
In a flask equipped with a nitrogen inlet tube, a condenser and a stirrer, 36.0 g of hydrophobic monomer 5 (Production Example 12), 84.0 g of acrylic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), 300 ml of ethyl alcohol and 0.05 M carbonic acid 30 ml of an aqueous sodium solution and 270 ml of a 0.1 M sodium bicarbonate solution were taken and mixed with stirring. While stirring was continued, nitrogen gas substitution was performed for 1 hour. A solution obtained by dissolving 2.0 g of ammonium persulfate in 20 ml of water was added thereto, and the reaction was further performed at 60 ° C. for 20 hours while continuing stirring. After completion of the reaction, the pH was adjusted to 7.0 using an aqueous sodium hydroxide solution, and ethyl alcohol was removed using a rotary evaporator to obtain an aqueous solution of copolymer 3 of the present invention.

<Production Example 19>
In a flask equipped with a nitrogen introduction tube, a condenser and a stirrer, 24.0 g of hydrophobic monomer 4 (Production Example 11), methoxypolyethylene glycol (9) methacrylate (manufactured by NOF Corporation, trade name “Blemmer PME-400” 72.0 g, 2-hydroxyethyl methacrylate (Tokyo Kasei Kogyo Co., Ltd.) 24.0 g, isopropyl alcohol 300 ml, 0.2 M aqueous potassium chloride solution 75 ml, 0.2N hydrochloric acid 15.8 ml and water 209.2 ml. Stir and mix. While stirring was continued, nitrogen gas substitution was performed for 1 hour. A solution prepared by dissolving 2.0 g of ammonium persulfate in 20 ml of water was added thereto, and the reaction was performed at 70 ° C. for 14 hours while continuing stirring. After completion of the reaction, the pH was adjusted to 7.0 using an aqueous potassium hydroxide solution, and isopropyl alcohol was removed using a rotary evaporator to obtain an aqueous solution of copolymer 4 of the present invention.

<Production Example 20>
In a flask equipped with a nitrogen inlet tube, a condenser and a stirrer, 9.0 g of hydrophobic monomer 3 (Production Example 10), polyethylene glycol (10) monoacrylate (manufactured by NOF Corporation, trade name “Blemmer AE-400” ] 45.0 g, 6.0 g of methyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 180 ml of ethylene glycol monomethyl ether and 120 m of 0.002N hydrochloric acid were mixed with stirring. While stirring was continued, nitrogen gas substitution was performed for 1 hour. A solution prepared by dissolving 1.0 g of ammonium persulfate in 10 ml of water was added thereto, and the reaction was continued at 65 ° C. for 16 hours while continuing stirring. After completion of the reaction, the pH was adjusted to 7.0 using an aqueous potassium hydroxide solution, and ethylene glycol monomethyl ether was removed with a rotary evaporator to obtain an aqueous solution of copolymer 5 of the present invention.

<Production Example 21>
In a flask equipped with a nitrogen inlet tube, a condenser and a stirrer, 24.0 g of hydrophobic monomer 6 (Production Example 13), methoxypolyethylene glycol (9) acrylate (manufactured by NOF Corporation, trade name “Blemmer AME-400” ] 90.0 g, 2-hydroxyethyl acrylate (Tokyo Kasei Kogyo Co., Ltd.) 6.0 g, isopropyl alcohol 300 ml, phosphate buffer solution (pH 6.8) (Nacalai Tesque Co., Ltd.) 300 ml and stirred. Mixed. While stirring was continued, nitrogen gas substitution was performed for 1 hour. A solution prepared by dissolving 2.0 g of ammonium persulfate in 20 ml of water was added thereto, and the reaction was continued at 65 ° C. for 16 hours while continuing stirring. After completion of the reaction, the pH was adjusted to 7.0 using an aqueous sodium hydroxide solution, and isopropyl alcohol was removed using a rotary evaporator to obtain an aqueous solution of the water-soluble copolymer 6 of the present invention.

<Production Example 22>
12.0 g of hydrophobic monomer 8 (Production Example 15), 100.8 g of acrylic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), 300 ml of ethyl alcohol and 0.05 M carbonic acid in a flask equipped with a nitrogen inlet tube, a condenser and a stirrer 30 ml of an aqueous sodium solution and 270 ml of a 0.1 M sodium bicarbonate solution were taken and mixed with stirring. While stirring was continued, nitrogen gas substitution was performed for 1 hour. A solution obtained by dissolving 2.0 g of ammonium persulfate in 20 ml of water was added thereto, and the reaction was further performed at 60 ° C. for 20 hours while continuing stirring. After completion of the reaction, the pH was adjusted to 7.0 using an aqueous sodium hydroxide solution, and ethyl alcohol was removed using a rotary evaporator to obtain an aqueous solution of copolymer 7 of the present invention.

<Production Example 23>
In a flask equipped with a nitrogen inlet tube, a condenser and a stirrer, 15.0 g of hydrophobic monomer 7 (Production Example 14), polyethylene glycol (9) monomethacrylate (manufactured by NOF Corporation, trade name “Blemmer PE-400” ] 45.0 g, 180 ml of ethyl acetate and 120 ml of ethyl alcohol were taken and mixed with stirring. While stirring was continued, nitrogen gas substitution was performed for 1 hour. A solution obtained by dissolving 0.5 g of benzoyl peroxide in 10 ml of ethyl alcohol was added thereto, and reflux was performed for 8 hours while continuing stirring. After completion of the reaction, 300 ml of water was added, and ethyl acetate and ethyl alcohol were removed by a rotary evaporator to obtain an aqueous solution of copolymer 8 of the present invention.

<Production Example 24>
A copolymer 9 was obtained in the same manner as in the method described in Production Example 1 of JP-A-2002-193730.

<Production Example 25>
An aqueous solution of copolymer 10 was obtained in the same manner as described in Production Example 12 of JP-A No. 2004-123726.

<4> External preparation for skin of the present invention The external preparation for skin of the present invention comprises a structural unit derived from the structural unit I and / or the structural unit II and a hydrophilic monomer, and if necessary, an arbitrary structural unit. The copolymer contained in the skeleton is contained as an essential component.

  The content of the copolymer in the external preparation for skin of the present invention is preferably 0.5 to 30% by mass, more preferably 1 to 25% by mass. Below the lower limit, the effect of the present invention may not be exhibited, which is not preferable. On the other hand, when the amount is not less than the upper limit value, it is not preferable because the preparation for the external preparation for skin, particularly the solubility in water, is low, and the preparation of the external preparation for skin containing the copolymer uniformly may be difficult.

  As an external preparation for skin of the present invention, external medicines such as ointments, cosmetics and the like can be suitably exemplified. Furthermore, examples of cosmetics include skin care such as cream, milky lotion, skin lotion, and beauty serum, make-up such as under makeup, foundation, eye color, mascara, and hair cosmetics such as hair tonic, hair liquid, and hair spray. .

The external preparation for skin of the present invention can contain, as an optional component, components that are usually used for external preparations for skin as long as the effects of the invention are not impaired. As such optional components, specifically,
Macadamia nut oil, avocado oil, corn oil, olive oil, rapeseed oil, sesame oil, castor oil, safflower oil, cottonseed oil, jojoba oil, coconut oil, palm oil, liquid lanolin, hydrogenated coconut oil, hydrogenated oil, molasses, hydrogenated castor oil, Oils such as beeswax, candelilla wax, carnauba wax, ibotarou, lanolin, reduced lanolin, hard lanolin, jojoba wax, waxes, liquid paraffin, squalane, pristane, ozokerite, paraffin, ceresin, petrolatum, hydrocarbons such as microcrystalline wax, Higher fatty acids such as oleic acid, isostearic acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, undecylenic acid, cetyl alcohol, stearyl alcohol, isostearyl alcohol, behenyl alcohol, Higher alcohols such as cutyldecanol, myristyl alcohol, cetostearyl alcohol, etc., cetyl isooctanoate, isopropyl myristate, hexyldecyl isostearate, diisopropyl adipate, di-2-ethylhexyl sebacate, cetyl lactate, diisostearyl malate, Di-2-ethylhexanoic acid ethylene glycol, dicaprate neopentyl glycol, di-2-heptylundecanoic acid glycerin, tri-2-ethylhexanoic acid glycerin, tri-2-ethylhexanoic acid trimethylolpropane, triisostearic acid trimethylol Synthetic ester oils such as propane, tetra-2-ethylhexanoic acid pentane erythritol, dimethylpolysiloxane, methylphenylpolysiloxane, diphenylpolysiloxane Linear polysiloxanes such as, cyclic polysiloxanes such as octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexanesiloxane, amino-modified polysiloxane, polyether-modified polysiloxane, alkyl-modified polysiloxane, fluorine-modified polysiloxane, etc. Oils such as silicone oils such as modified polysiloxanes, fatty acid soaps (sodium laurate, sodium palmitate, etc.), anionic surfactants such as potassium lauryl sulfate, alkylethanol triethanolamine ether, stearyltrimethylammonium chloride, chloride Cationic surfactants such as benzalkonium and laurylamine oxide, imidazoline-based amphoteric surfactants (2-cocoyl-2-imidazolinium hydroxide-1-cal Boxyethyloxy disodium salt, etc.), betaine surfactants (alkyl betaine, amide betaine, sulfobetaine, etc.), amphoteric surfactants such as acylmethyltaurine, sorbitan fatty acid esters (sorbitan monostearate, sorbitan sesquioleate, etc.) ), Glycerin fatty acids (such as glyceryl monostearate), propylene glycol fatty acid esters (such as propylene glycol monostearate), hydrogenated castor oil derivatives, POE sorbitan fatty acid esters (POE sorbitan monooleate, polyoxyethylene monostearate) Sorbitan, etc.), POE sorbite fatty acid esters (POE-sorbite monolaurate, etc.), POE glycerin fatty acid esters (POE-glycerol monoisostearate, etc.), POE fat Acid esters (polyethylene glycol monooleate, POE distearate, etc.), POE alkyl ethers (POE2-octyldodecyl ether, etc.), POE alkyl phenyl ethers (POE nonylphenyl ether, etc.), Pluronic types, POE / POP alkyl ethers (POE / POP2-decyltetradecyl ether, etc.), Tetronics, POE castor oil / hardened castor oil derivatives (POE castor oil, POE hardened castor oil, etc.), nonionic surfactants such as sucrose fatty acid ester, alkyl glucoside Polyethylene glycol, glycerin, 1,3-butylene glycol, erythritol, sorbitol, xylitol, maltitol, propylene glycol, dipropylene glycol, diglycerin, isoprene Moisturizing composition of polyalcohols such as coal, 1,2-pentanediol, 2,4-hexylene glycol, 1,2-hexanediol, 1,2-octanediol, sodium pyrrolidonecarboxylate, lactic acid, sodium lactate Classification, guar gum, quince seed, carrageenan, galactan, gum arabic, pectin, mannan, starch, xanthan gum, curdlan, methylcellulose, hydroxyethylcellulose, carboxymethylcellulose, methylhydroxypropylcellulose, chondroitin sulfate, dermatan sulfate, glycogen, heparan sulfate, hyaluron Acid, sodium hyaluronate, tragacanth gum, keratan sulfate, chondroitin, mucoitin sulfate, hydroxyethyl guar gum, carboxymethyl guar gum, dextran , Keratosulfuric acid, locust bean gum, succinoglucan, caronic acid, chitin, chitosan, carboxymethyl chitin, agar, polyvinyl alcohol, polyvinyl pyrrolidone, carboxyvinyl polymer, sodium polyacrylate, polyethylene glycol, bentonite and other thickeners, Lower alcohols such as ethanol and isopropanol, hexyl diethylaminohydroxybenzoylbenzoate, t-butylmethoxybenzoylmethane, paraaminobenzoic acid UV absorber, anthranilic acid UV absorber, salicylic acid UV absorber, cinnamic acid UV absorber UV absorbers, vitamin A or its derivatives, vitamin B6 hydrochloride, vitamin B6 tripalmitate, vitamin B6 dioctanoate, vitamin B2 or its derivatives, vitamin B12, vitamin B15 such as vitamin B15 or derivatives thereof, α-tocopherol, β-tocopherol, γ-tocopherol, vitamin E such as vitamin E acetate, vitamin D, vitamin H, pantothenic acid, panthetin, pyrroloquinoline quinone, etc. Of these, vitamins can be preferably exemplified.

  The skin external preparation of this invention can be prepared by processing the said essential component and an arbitrary component by a conventional method.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, it cannot be overemphasized that this invention is not limited only to these Examples.

<Examples 1-3, Comparative Examples 1-3>
According to the formulation shown in Table 3 below, skin lotions that are external preparations for skin of the present invention and skin lotions for comparative examples were prepared. That is, the mixture of component (a) shown in Table 1 was stirred and mixed at room temperature to obtain a uniform solution. The mixture of the component (b) was heated to 75 ° C. and stirred to obtain a uniform solution. While stirring the mixture of component (a), the mixture of component (b) cooled to room temperature was slowly added, and the two solutions were mixed to obtain a lotion. The numbers in Table 3 represent mass%.

Test Example 1 Skin Moisturizing Test The test was conducted in a room at 20 ° C. and 50% relative humidity for five panelists. The measurement site was washed with warm water at 37 ° C. for 30 seconds, allowed to rest for 20 minutes, and then measured. For the skin on the inner side of the forearm, the skin moisture content at the planned test site was measured with SKICON-200EX (IBS) on the day before the test scheduled date (-1 day). Thereafter, gauze (2 cm × 2 cm) impregnated with a 5% sodium lauryl sulfate aqueous solution was contacted for 30 minutes. The skin moisture content was measured on the next day (day 0) SKICON-200EX, and then the lotions of Examples 1 to 3 and the lotions of Comparative Examples 1 to 3 were applied. The test sample was applied three times a day. The skin moisture content was measured again 1 day and 2 days after application. At the same time, an untreated control test in which no test sample was applied was also performed. In addition, the measured value was made into the average value of five panelists. The results are shown in Table 4.

<Test Example 2> Measurement of adhesiveness The cosmetic lotions of Examples 1 to 3 and 0.1 ml of the cosmetics of Comparative Examples 1 to 3 were applied to an area of 1.2 cmφ on the slide glass, and the cosmetic solution was in use. , And dried at 40 ° C. and a relative humidity of 60% for 1 hour to prepare a test film. The adhesion of this test film was evaluated using a handy pressure tester KES-G5 (manufactured by Kato Tech Co., Ltd.). The adhesiveness was expressed as an adhesive force (g) when the head of the apparatus was peeled off from the coating film. That is, the higher this value, the higher the adhesiveness of the coating film. The results are shown in Table 4.

<Test Example 3> Measurement of dynamic friction coefficient 1 cm from the longitudinal end of a strip (15 cm × 5 cm) of a synthetic leather made of polyurethane similar to human skin (previously cleaned with ethanol before the test), 3 cm × 3 cm × In the range of 3 cm, the skin lotions of Examples 1 to 3 and the skin lotions of Comparative Examples 1 to 3 are uniformly applied and fixed to the experimental table with double-sided tape. On the other hand, the same synthetic leather piece 3 cm × 3 cm is attached to a jig for placing a load with double-sided tape. The jig was placed on the coated surface of the sample so that the surface of the synthetic leather faced, a load of 200 g was placed, and the frictional resistance was measured with a surface property tester (Trilab Handy Love Tester Type TL701). The measurement conditions were a sweep speed of 200 mm / sec, a sweep distance of 10 cm, a repeat count of 10 times, and the average of the 10 frictional resistance values in the forward path was defined as the dynamic frictional resistance value. The dynamic friction coefficient was calculated by dynamic friction resistance value / load. A smaller dynamic friction coefficient indicates that there is no resistance to slipping. The results are shown in Table 4.

<Test example 4> Evaluation of stickiness and squeak The stickiness and squeak of the lotions of Examples 1 to 3 and Comparative Examples 1 to 3 being applied on the skin by five skilled evaluators according to the following evaluation criteria. Sensory evaluation was performed.
Stickiness 1: Feels stickiness considerably 2: Feels stickiness 3: Feels stickiness slightly 4: Feels stickiness very slightly 5: Does not feel stickiness at all
Squeak 1: Feels squeak fairly 2: Feels squeak 3: Feels squeak slightly 4: Feels squeak slightly 5: Does not feel squeak at all
In addition, evaluation was performed by setting the skin lotion of Comparative Example 1 to 3.0, and the average value of the scores of 5 people was used as the sample score. The results are shown in Table 4.

As is apparent from Table 4, the external preparation for skin of the present invention has excellent skin moisture retention, low adhesion of the coating film in use, and as a result, does not feel sticky and has a low coefficient of dynamic friction, resulting in squeaking. It was proved that it was excellent in the feeling of use.

<Examples 4-6, Comparative Examples 4-6>
According to the formulation shown in Table 5 below, an emulsion which is an external preparation for skin of the present invention and an emulsion of a comparative example were prepared. That is, the mixture of component (A) and the mixture of component (B) shown in Table 5 were heated to 80 ° C. and mixed by stirring to obtain uniform solutions. While maintaining the temperature at 80 ° C., while stirring, the mixture of (b) was gradually added to the mixture of component (a) to emulsify, and stirred to cool to obtain an emulsion. The numbers in Table 5 represent mass%. Using the emulsions obtained in Examples 4 to 6 and Comparative Examples 4 to 6, skin moisture retention, adhesiveness, dynamic friction coefficient, stickiness, and squeak were evaluated in the same manner as in Test Examples 1 to 4. In the evaluation of stickiness and blotch, the score of Comparative Example 4 was set to 3.0. The results are shown in Table 6.

As is apparent from Table 6, even in the emulsion, the external preparation for skin of the present invention is excellent in skin moisture retention, and the adhesiveness of the coating film in use is low, resulting in no stickiness and a low coefficient of dynamic friction. As a result, it was proved that it was excellent in use feeling that it did not feel squeak.

<Examples 7-9, Comparative Examples 7-9>
According to the formulation shown in Table 7 below, a cream which is a skin external preparation of the present invention and a cream of a comparative example were prepared. That is, the component (b) was dispersed in the mixture of the component (a) shown in Table 7. The mixture of component (a) containing dispersed component (b) was heated to 80 ° C. while stirring, and the mixture of component (c) heated to 80 ° C. was gradually added to emulsify. The obtained emulsion was stirred and cooled to obtain a cream. The numbers in Table 7 represent mass%. Using the creams obtained in Examples 7 to 9 and Comparative Examples 7 to 9, skin moisture retention, adhesiveness, coefficient of dynamic friction, stickiness, and squeak were evaluated in the same manner as in Test Examples 1 to 4. In the evaluation of stickiness and stains, the score of Comparative Example 7 was set to 3.0. The results are shown in Table 8.

As can be seen from Table 8, even in creams, the external preparation for skin of the present invention is excellent in skin moisture retention, the adhesiveness of the coating film in use is low, and as a result, there is no stickiness and the coefficient of dynamic friction is low. As a result, it was proved that it was excellent in use feeling that it did not feel squeak.

<Examples 10-12, Comparative Examples 10-12>
According to the formulation shown in Table 9 below, a foundation which is an external preparation for skin of the present invention and a foundation for a comparative example were prepared. That is, the mixture of the component (I) and the mixture of the component (B) shown in Table 9 were heated to 80 ° C. and mixed by stirring to obtain uniform solutions. Add (c) to component (a), disperse using disper, and while stirring at temperature of 80 ° C., gradually add component (b) to emulsify, stir and cool. In addition, the numbers in Table 9 represent mass%, and using the foundations obtained in Examples 10 to 12 and Comparative Examples 10 to 12, the same method as in Test Examples 1 to 4 was used. Moisturizing property, adhesiveness, coefficient of dynamic friction, stickiness, and creaking were evaluated, and in the evaluation of stickiness and creaking, the score of Comparative Example 10 was set to 3.0, and the results are shown in Table 10.

As is apparent from Table 10, even in the make-up product, the external preparation for skin of the present invention is excellent in skin moisture retention, and the adhesiveness of the coating film in use is low, resulting in no stickiness and a coefficient of dynamic friction. As a result, it was proved that it was excellent in use feeling that it did not feel squeak.

The present invention can be used for cosmetics.

Claims (7)

One or more structural units derived from a hydrophobic monomer represented by the following general formula (I) or (II) and one or more structural units derived from a hydrophilic monomer consisting of the following group A As an essential constituent unit, and the proportion of one or two or more constituent units derived from the hydrophobic monomer to the total constituent units is 1 to 40% by mass, and one or more constituent units derived from the hydrophilic monomer The skin external preparation characterized by containing the copolymer which the ratio to the total structural unit of 2 or more types of structural units is 30-95 mass%, and may have another structural unit.
Formula (I)
(I)
(In the general formula (I), R ¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ² and R ³ may be the same or different, have no ring structure and have a branched carbon number. Represents an acyl group of 6 to 22. P represents a group in which an OH group is eliminated from a trivalent alcohol.
Formula (II)
(II)
(In the general formula (II), R ⁴ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ⁵ , R ⁶ and R ⁷ may be the same or different and do not contain a ring structure and have a branch. Represents an acyl group having 6 to 22 carbon atoms, Q represents a group in which an OH group is eliminated from a tetravalent alcohol.

Group A: polymerizable carboxylic acid, hydrophilic monomer represented by the following general formula (III) general formula (III)
(III)
(In the general formula (III), R ⁸ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ⁹ represents an alkylene group having 2 to 4 carbon atoms which may have a hydroxyl group, and R ¹⁰ represents hydrogen. An atom, an aromatic hydrocarbon group having 6 to 10 carbon atoms, an aliphatic hydrocarbon group having 1 to 14 carbon atoms, or an acyl group having 1 to 12 carbon atoms, and n represents an integer of 6 to 40.) The hydrophobic monomer represented by the general formula (I) is a hydrophobic monomer represented by the following general formula (IV), and the hydrophobic monomer represented by the general formula (II) is represented by the following general formula (V) The external preparation for skin according to claim 1, which is a hydrophobic monomer represented by the formula:
Formula (IV)
(IV)
(In the general formula (IV), R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ¹² and R ¹³ may be the same or different, have no ring structure, and have a branched carbon number. It represents an acyl group having 10 to 22 or a C 6-9 acyl group having two or more branches that does not contain a ring structure, and S represents a group in which an OH group is eliminated from a trivalent alcohol. )
General formula (V)
(V)
(In the general formula (V), R ¹⁴ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ¹⁵ , R ¹⁶ , and R ¹⁷ may be the same or different and do not include a ring structure and have a branch. Represents an acyl group having 10 to 22 carbon atoms, or an acyl group having 6 to 9 carbon atoms having two or more branches that does not contain a ring structure, and T represents a group in which an OH group is eliminated from a tetravalent alcohol. Represents.) The skin external preparation according to claim 1 or 2, wherein the hydrophilic monomer represented by the general formula (III) is a hydrophilic monomer represented by the following general formula (VI).
Formula (VI)
(VI)
(In the general formula (VI), R ¹⁸ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ¹⁹ represents a hydrogen atom, an aromatic hydrocarbon group having 6 to 10 carbon atoms, or an aliphatic group having 1 to 14 carbon atoms. A hydrocarbon group or a C1-C12 acyl group is represented.m represents an integer of 6-40.)   The external preparation for skin according to any one of claims 1 to 3, wherein the polymerizable carboxylic acid is acrylic acid and / or methacrylic acid.   The skin external preparation according to any one of claims 1 to 4, wherein the trihydric alcohol is selected from the group consisting of glycerin, trimethylolpropane, and trimethylolethane.   The tetravalent alcohol is a tetravalent alcohol selected from the group consisting of diglycerin, pentaerythritol, erythritol, D-threitol, and L-threitol. The skin external preparation as described. It is a cosmetic, The skin external preparation of any one of Claims 1-6 characterized by the above-mentioned.