Saturday, June 19, 2010
Question: Differences between cetrimonium bromide and cetrimonium chloride?
Having said this, when you are buying bath and body supplies, you aren't getting the pure version of a product. When I buy cetrimonium bromide, I'm buying 27% to 29% cetrimonium bromide with cetearyl alcohol making up the rest, and it comes in a waxy flake format. When I buy cetrimonium chloride, I'm buying a liquid with about 25% active ingredients with preservatives and water making up the rest.
It's hard to compare different surfactants between companies because each brand is different depending upon how much of the active surfactant is in the solution, other ingredients added by the manufacturer (preservatives, conditioning agents, thickeners, and so on). For instance, I generally use SLeS in my body washes, but thought I'd try ALeS because my SLeS bottle was almost empty. The ALeS thickened the mixture up so much, I turned it into Jell-O with 1% Crothix - I'd normally need 2% for SLeS to thicken it nicely. This has more to do with the extras in the SLeS vs. ALeS mixture than the surfactants themselves, but it's still very relevant when you're making a product. And then we have to consider the moles of ethoxylated molecules...
Buying cosmetic supplies is like buying salt - we aren't buying straight NaCl. Just as table salt contains iodine, dessiccants, stuff to help it pour out, we find the same thing with our supplies. You aren't buying straight SLS or concentrated cetrimonium chloride. You're buying something containing water, preservatives, thickeners, conditioners, and so on. And each manufacturer will add or remove something that will make their product different from their competitors. And then there's differences in moles of ethoxylation and titer points and all those other lovely things that make cosmetic chemistry so interesting!