OctamethylCyclotetrasiloxane
八甲基環四矽氧烷
分子式：C8H24O4Si4
分子量：296.61
疏水膜、防水劑，可作為矽油之替代成份。
Commission Regulation (EU) 2018/35 of 10 January 2018
Shall not be placed on the market in wash-off cosmetic products in a concentration equal to or greater than 0,1 % by weight of either substance, after 31 January 2020.
http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=uriserv:OJ.L_.2018.006.01.0045.01.ENG&toc=OJ:L:2018:006:TOC