Monday, February 28, 2011

Learning to formulate: More tweaking of light lotions

We know that a light lotion has about an 80% water phase, 19% oil phase, and 0.5% to 1% preservative.  And we know we can tweak that lotion silly with any ingredients we want as long as we stay within those guidelines if we want it to remain the consistency of a light lotion (You can reduce the water, increase the oil phase, and make your way to the 70% water lotion or even 60% lotion, if you wish!)

So what kind of changes can we make? Well, it depends on the goals of your lotion!

Let's say we want something that's a little thicker but still want an 80% water amount. We can add a butter to the mix - say 5% of something like cocoa butter, mango butter, or shea butter - or we can add more thickener. Adding stearic acid will make it thicker than cetyl alcohol or cetyl esters. I'd suggest using about 2% to 3% thickener in a recipe like this.

So let's say we want a more occlusive lotion and we don't want to use dimethicone for that purpose. Let's use 5% cocoa butter and 10% oils. This will give us a thicker, more occlusive lotion than one without cocoa butter. Or we could use 5% cocoa butter, 2% stearic acid or cetyl alcohol, and 8% oils to make a much thicker, occlusive lotion than the original.

Or if you wanted to make something occlusive with dimethicone, you could use 2% dimethicone (in the cool down phase), 3% cocoa butter, 2% stearic acid or cetyl alcohol, and 8% oils.

Or we could use something like babassu oil - did I mention I love this stuff? - along with a less greasy oil (let's say camellia seed oil as I have a lot at home) and some IPM and BTMS-50 to make a drier feeling product. Say 5% babassu oil, 8% camellia seed oil, 2% IPM, and replace the emulsifier with BTMS-50 for a light, non-greasy feeling product.

Or let's say we want to make something that would be considered oil free (although technically the C12-15 alkyl benzoate lotion was oil free because we used an ester instead of an oil). We could use 10% esters, 3% cetyl alcohol, and 2% cetyl esters, cetearyl alcohol, stearic acid, or another thickener to make an oil-free but thicker product.

There are hundreds - if not thousands - of different combinations you can try in all the lotions I've been writing about here. It all depends on what you want in a product!

Join me tomorrow for a quick summary of what we've learned so far!

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