Sunday, December 22, 2013
What do you want to know? Is there a limit to what we can include in the cool down phase?
What do you want to know post, and I'm going to do my best to answer them! (You've got quite the curious mind, Marjo! It's great!)
What are the boundaries of the additives phase? I mean, how far can or should you go in the cooling phase with adding things without breaking the emulsion?
This is a good question. I've never seen anything that says there is a limit, but we feel there should be! If you think about it, the cool down phase is still pretty warm - 45˚C or 113˚F - so we aren't putting a ton of things into a cold lotion, we're putting those things into a warm lotion.
I find my cool down phase rarely goes above 10% of the total lotion amount. For instance, I generally have 0.5% liquid Germall Plus and 1% fragrance oil, and I might add 2% dimethicone, 2% cyclomethicone, 2% panthenol, and 1% Vitamin E. I might add some powdered extracts - say 0.5% powdered chamomile extract or up to 5% niacinamide - as well, but I tend to dissolve those first to make it easier to mix them in. Facial products can end up with a lot of
I find a lot of hair care ingredients are grumpy in warmer temperatures, so I think the highest cool down phases I have come in my conditioner or leave in conditioner category. My favourite leave in has dimethicone, cyclomethicone, and panthenol at 2% each, honeyquat at 3%, volumizing complex at 5%, and preservative and fragrance, for a total cool down phase of 15.5%. And it stays well emulsified, even though there's 1% to 2% of a good emulsifier (Incroquat BTMS-50) and up to 3% of not so great emulsifiers (cetrimonium chloride and Incroquat CR).
So what's the answer? I'm not really sure. I think it would depend upon what was being added. If you're adding a ton of oil based ingredients, I think you'll have a smaller cool down phase potential than if you were adding some powders and water soluble things, like extracts or cosmeceuticals. I think keeping it around 10% is a good idea, but you could go higher. You'd have to see what happens when you go higher!
As a note, I scoured all the textbooks I have on cosmetic chemistry and didn't find a thing. I admit I didn't read them from cover to cover again, but I did do some serious scanning that took quite some time. I am open to any information you might have that will point me to a reference that contains this information! I'm going crazy not knowing!