The present invention provides an O/W type emulsion having a volume median diameter of not more than 100 nm and containing a compound represented by the formula (1)
wherein Xa and Xb are each independently X1, X2 or a 1,4-piperazinediyl group;
s is 1 or 2,
R4 is an alkyl group having 1-6 carbon atoms,
na and nb are each independently 0 or 1,
R1a, R1b, R2a and R2b are each independently an alkylene group having 1-6 carbon atoms,
Ya and Yb are each independently an ester bond, or the like, and
R3a and R3b are each independently a liposoluble vitamin residue or the like.
本发明提供了一种体积中值直径不超过 100 纳米的 O/W 型乳液,其中含有一种由式(1)表示的化合物
其中 Xa 和 Xb 各自独立地为 X1、X2 或 1,4-
哌嗪二基;
s 为 1 或 2、
R4 是具有 1-6 个碳原子的烷基、
na 和 nb 分别独立地为 0 或 1、
R1a、R1b、R2a 和 R2b 各自独立地为具有 1-6 个碳原子的亚烷基、
Ya 和 Yb 各自独立地为酯键或类似键,以及
R3a 和 R3b 各自独立地为脂溶性
维生素残基或类似物。