JP-7856223-B2 - Polyethers, cosmetic bases, and cosmetics

Inventors

• 村上 大河
• 関口 孝治

Assignees

• 日油株式会社

Dates

Publication Date

20260511

Application Date

20250324

Priority Date

20240329

Claims (2)

1. Formula (1): [In the formula, R1 , R2 , and a number of R3s are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms.] The ratio of (number of hydrogen atoms in R1 to R3 ) / (number of hydrocarbon groups in R1 to R3 ) is 20 or less. GL is a glycerol residue, and is of formula (2), formula (3a), or formula (3b): (In the formula, * indicates the bond position with R3 .) It is a base represented by, CH₂CH₂O is an ethylene glycol residue, CH2CH2CH2O is a 1,3 - propanediol residue, C n H 2n O is an alkanediol residue with 4 to 8 carbon atoms. a, b, c, and d are the average degrees of polymerization of GL , CH₂CH₂O , CH₂CH₂CH₂O , and CnH₂nO , respectively. a is a number between 0 and 30. b is a number between 0 and 80. a + b is a number between 1 and 80. c is a number between 0 and 60. d is a number between 0 and 60. c + d is a number between 1 and 70. (a+b)/(c+d) is a number between 0.2 and 8, and n is a number between 4 and 8. A polyether represented by, A cosmetic base comprising a polyether in which, when GL is present, all of the groups represented by formula (2), formula (3a), and formula (3b) are present, and the molar ratio of the group represented by formula (2) to (the group represented by formula (3a) and the group represented by formula (3b)) is 40/60 to 99/1.
2. A cosmetic composition comprising the cosmetic base described in claim 1 in an amount of 0.1 to 30% by mass relative to the total cosmetic composition.

Description

This invention relates to polyethers, cosmetic bases, and cosmetics. Polyethers, produced by ring-opening addition polymerization of cyclic ethers such as ethylene oxide and propylene oxide, or by dehydration condensation of polyhydric alcohols, are used in various applications, such as cosmetic bases, because the balance of hydrophilicity and lipophilicity, as well as molecular weight, can be easily controlled. In the field of skincare cosmetics, polyhydric alcohols such as glycerin and water-soluble polymers such as hyaluronic acid are often incorporated to enhance moisturizing effects. However, cosmetics obtained by incorporating large amounts of polyhydric alcohols and water-soluble polymers can sometimes feel sticky or have poor absorption into the skin, leading to a deterioration in usability. Therefore, Patent Documents 1 and 2 disclose cosmetic compositions containing specific polyethers that can achieve both high moisturizing effects and a pleasant, non-sticky feel. Japanese Patent Publication No. 2004-83541Japanese Patent Publication No. 2020-105123 In this specification, numerical ranges defined using "～" include the numbers at both ends (upper and lower limits) of "～". For example, "2～5" means 2 or more and 5 or less. <Polyether> The polyether of the present invention is of the following formula (1): It is represented as follows. The polyether of the present invention may be used alone or in combination of two or more types. The definitions of the symbols in formula (1) will be explained in order below. In formula (1), R1 , R2 , and a number of R3 are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. Polyethers having hydrocarbon groups with 21 or more carbon atoms may have reduced moisturizing effect, transparency, or low-temperature stability in cosmetics. Examples of hydrocarbon groups include alkyl groups, alkenyl groups, cycloalkyl groups, aryl groups, and aralkyl groups. The hydrocarbon group is preferably an alkyl group or an alkenyl group. Both alkyl and alkenyl groups may be linear or branched. The hydrocarbon group having 1 to 20 carbon atoms is preferably an alkyl group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms, and more preferably an alkyl group having 1 to 6 carbon atoms. Examples of alkyl groups having 1 to 6 carbon atoms include methyl, ethyl, propyl, butyl, sec-butyl, tert-butyl, and hexyl groups. The hydrocarbon group having 1 to 20 carbon atoms is most preferably a methyl group. The ratio of (number of hydrogen atoms in R1 to R3 ) / (number of hydrocarbon groups in R1 to R3 ) (hereinafter sometimes referred to as "hydrogen atom/hydrocarbon group") is 20 or less, preferably 15 or less, and more preferably 10 or less, from the viewpoint of suppressing stickiness, transparency, and low-temperature stability in cosmetics. Note that the hydrogen atom/hydrocarbon group ratio may be 0. Furthermore, in this specification, when the number of hydrocarbon groups in R1 to R3 is 0, the hydrogen atom/hydrocarbon group ratio is interpreted as ∞ (infinity). As described in the Examples section below, the hydrogen atom/hydrocarbon group ratio of a polyether (i.e., (number of hydrogen atoms in R1 to R3 ) / (number of hydrocarbon groups in R1 to R3 )) is calculated from the integral of the signal of the carbonyl carbon derived from the acetyl group and the signal of the terminal CH3 derived from the hydrocarbon group, obtained by 13C -NMR measurement when the polyether is acetylated, using the following formula: The hydrogen atom/hydrocarbon group can be calculated by the integral value of the signal of the carbonyl carbon derived from the acetyl group / the integral value of the signal of the terminal CH3 derived from the hydrocarbon group. The acetylation method described above is not particularly limited, and known methods can be used, but the method using pyridine and acetic anhydride, as described in the Examples section below, is preferred. Furthermore, 13C -NMR measurement can be performed as described in the Examples section below. If necessary, hydrogen atoms/hydrocarbon groups can be calculated by combining 13C -NMR measurements with other measurements such as 1H -NMR, DEPT135, and 2D NMR (HHCOSY, HMQC, HMBC, NOESY). In formula (1), GL is a glycerol residue. Here, "glycerol residue" refers to formulas (2) , ( 3a ) , or (3b) : (In the formula, * indicates the bond position with R3 .) This refers to the base represented by formula (2), formula (3a), and formula (3b) . Hereinafter , "the base represented by formula (2)", "the base represented by formula (3a)", and "the base represented by formula (3b)" may be abbreviated as "base (2)", "base (3a)", and "base (3b)", respectively. When GL (glycerol residue) is present in the polyether of the present invention, all of groups (2) , ( 3a ) , and (3b) may be present. Preferably, when GL (glycerol residue) is present in the polyether of the present invention, all of groups (2)