Sunday, December 22, 2013

What do you want to know? Is there a limit to what we can include in the cool down phase?


Marjo asks quite a few questions on the 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).

If you're making lotions, I think we have to worry about emulsification. If you're making other products, I don't think there's a limit to what you could add in the cool down phase. I've never had a problem adding anything to a cold shampoo or body wash as the heating tends to be more about dissolving powders or getting rid of contamination rather than emulsifying the ingredients.

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! 

4 comments:

Marjo said...

That clarifies a lot susan thank you for taking the time to answer my question! I am afraid breaking the emulsion so tend to think i have to really be carefull here for the cool down phase feels like -after emulsion- state

scd said...

Susan, I'm curious about Niacinamide; can this cosme be put either in the Water phase or cool down phase of a would-be lotion or eye lotion without ruining it's efficacy?

Thanks brainiac!

Susan Barclay-Nichols said...

Hi scd. Check out the post on niacinamide to see the answer to your questions.

scd said...

Thanks for the link to niacinamide; i have seen it before and was confident that it was a heated water phase ingredient but on another one of your recipes you had added niacinamide in your cool down phase.. maybe its ok to use in either or.. Happy holdiays!