I'm going to let you in on a little secret...Being greener or Ecocert doesn't mean it's good for your skin. It might say something about how the ingredient was processed or where the ingredients come from, but it says nothing about how the ingredient will affect your skin. It might dry it out. It might irritate it. It might not moisturize well. It might not cleanse well. It might be completely awesome at all those things. We don't know until we try the ingredient in our products.
Let's say you make a green shampoo that contains decyl glucoside, water, and preservative. You can have something with a really high pH because decyl glucoside is generally over pH 8. You can have something that dries out your scalp and hair because you haven't included anything to increase the mildness, which is the key to making anything with surfactants.
Surfactants, by their very nature, are irritating to our skin. The goal when creating surfactant based products is to reduce the irritation to our skin by using milder cleansers, creating blends that enhance mildness, and adding ingredients like cationic polymers, proteins, or emollients.
I'm going to leave you to read the rest of the post on increasing mildness before continuing on...go ahead...I'll wait. You might want to read the post on the chemistry of our skin as well. I encourage it...we've got time. Oh, you're back. Excellent!
So let's say we have a shampoo that looks like this (this is a made up recipe, untested, so try it at your own risk)....
PRETEND GREEN SHAMPOO RECIPE
40% decyl glucoside
preservative suitable for a shampoo
water to 100%
We have nothing in here to mitigate the irritation that the decyl glucoside might cause. We have no emollients, we have no cationic polymers, and we have no proteins. We have a high concentration of a mild surfactant, but it's still a high concentration with no mitigators. And we might have a high pH. So what can we do? We can add these various ingredients to the product or reduce the concentration of decyl glucoside.
We can add some emollient ingredients - say, something like coconut oil - but there's a problem...decyl glucoside isn't a great emulsifier, so you're going to end up with oil floating on the top of your product. You'll have to use something that is a good emulsifier or use a water soluble oil to get those emollients into the product.
We can add a cationic polymer, but I don't think there are any that are considered green. Maybe Honeyquat?
What about adding a protein? If you aren't using any other mildness increasers, you might want to consider using a protein like hydrolyzed oat protein or hydrolyzed silk protein at 5%. If you're using itin combination with other ingredients, then use as little as 2% in the heated water phase.
humectant? Glycerin is a great choice here, and I'd encourage you to use it at up to 5%. However, if you have frizzy hair or hair that gets big when exposed to a lot of water, glycerin isn't necessarily your friend and might result in some slightly poofier hair than you expected.
And what about a thickener? Xanthan gum might thicken your mixture, but it doesn't do anything for incorporating mildness, so I'd suggest something like Crothix or Ritathix DOE, both of which will thicken the product and increase the mildness with their emolliency, but neither is Ecocert, so they don't fit the bill.
Consider adding another surfactant that can mitigate irritation, like cocamidopropyl betaine, which will also help to thicken the mixture. At a mere 10% this surfactant can turn your product from all right to freakin' awesome!
Join me tomorrow for more fun formulating!