What is cyclopentasiloxane

Kalisa’s quest: The last time I was having my hair done, I asked my stylist to help me find some product for my hair. I told him that I’d tried several different things, but I just can’t achieve the look I’m going for. I want to know how to get that slightly wet, slightly “greasy” look, without it being “crunchy,” and he said, “You need a product with silicone” and sold me something [Bumble & Bumble defrizz] with “cyclopentasiloxane” as the main ingredient. Why do you suppose he recommended silicone and what purpose does it serve in a hair product?

The Beauty Brains respond:

We’re glad your stylist recommended this silicone because it’s one of our mostest favorite ingredients in the whole wide world! In fact, the Left Brain has even written a short musical tribute to Cyclopenatasiloxane (or ‘Siloxane, as we like to refer to it.) I’m not really supposed to share it with you, but what the heck….

(sung to the tune of the “Troggs’ Wild Thing”)

‘Siloxane…you make my hair shine…

You make everything


I said ‘Siloxane…

‘Siloxane, I think I love you

But I wanna know for sure

Comb in, hair is bright

I love you

It kind of brings a tear to your eye, doesn’t it? Now, on to your answer.

Why is cyclopentasiloxane used in cosmetics?

Cyclopentasiloxane (or CPS for short) is one of many types of silicones. In general, silcones are known for their ability to lubricate, waterproof and provide shine. (Think “Armor All” for your head.) There are many types of silcones – some have a very heavy, sticky consistency and others are very lightweight. CPS is a water-thin so it’s very good at dispersing thicker, greasier silicones. For this reason it’s often used in combination with dimethicone. It is also volatile, which means it will evaporate. So, not only does it help spread heavier silicones but it doesn’t leave your hair feeling weighed down after it’s done.

In rinse off products CPS is used to create a very lubricious, wet slippery feel. In the kinds of leave on styling products that you asked about, it can give you the wet but not crunchy look you’re seeking. Of course, the other ingredients in the formula make a difference too, but that’s why your stylist recommended something based on CPS.

The Beauty Brains bottom line:

CPS is one of our fave ingredients – it provides a very elegant feel on the hair, it works well with other ingredients, and it can be used in leave on and rinse off products. What more could you ask for from an ingredient?