Cyclomethicone is a fully methylated cyclic siloxane containing repeating units of the formula:
[–(CH3)2SiO–]n,
in which nis 4,5,or 6,or a mixture of them.It contains not less than 98.0percent of (C2H6OSi)n,calculated as the sum of cyclomethicone 4,cyclomethicone 5,and cyclomethicone 6,and not less than 95.0percent and not more than 105.0percent of the labeled amount of any one or more of the individual cyclomethicone components.