| 摘要 |
<p>Alkyl-aryl 1,3 - propanedione silicone derivative characterized in that said derivative is siloxane having at least one unit expressed by the general formula 1 as shown below and other unit which can exist in said siloxane is expressed by a general formula of O4-r/2 SiR<5>r, and an external preparation for skin with said derivative compounded therein. <CHEM> (Herein; R<1>: A hydroxyl group, an alkyl group having 1 to 8 carbon atoms , or an alkoxy group having 1 to 8 carbon atoms R<2>: An alkyl group having 1 to 7 carbon atoms R<3>: A bivalent alkylene group or an oxyalkylene group having at least 2 carbon atoms R<4>, R<5>: An alkyl group, a phenyl group, or a trimethylsiloxy group having 1 to 4 carbon atoms m: An integer from 0 to 3 p: 0 or 1 q,r: An integer from 0 to 3.) An excellent UV-A absorbing capability and compatibility with a silicone-based base are provided.</p> |
