Thursday, March 10, 2011
What's in the mail bag?
From Aesthete (in this post): I don't have sodium hydroxide, is there something else I can use to increase ph?
You can use another alkaline ingredient, like borax (pH about 9.5) or sodium bicarbonate, and those might change the consistency of the product so you'll want to try it out on a small batch before you use this as your regular pH adjuster. The reason lye is chosen is because it doesn't tend to have a huge impact on the final skin feel of the product, so if you have to raise the pH regularly, investing in a small bag might be a good idea (it's not an expensive ingredient!).
From Kat (in this post): I made a recipe which included a small amount of borax (mixed into the wet ingredients, not dissolved, then drizzled into the dry mix). They were really nice in the tub, though the bombs themselves developed a large crack in the middle (I'm not sure if this was caused by the addition of borax or not). I'm wondering what your thoughts are on this. What's the benefit of using borax and is it safe?
I think the borax is included in the recipe to increase the alkalinity of the product (to be part of the sodium bicarbonate/baking soda mix) to increase the reaction with the acidic part of the product (the citric acid). I'm not sure why it's there and you can make a great bath bomb without it. As for the cracks, this could be any number of things, but I find this happens when I don't have enough liquid in the product. Bath bombs are a lot trickier than they seem! Borax is a safe ingredient, but I'm not sure why it's in the recipe. You can leave it out, if you want.
From Katherine (in this post): I'm also interested in ceramides. Is there any real value in using an expensive ingredient like that in a skin cleanser? I'm also interested in knowing how well the various "extras" play together. A specific one is Willow Bark Extract & things like ceramides or other extracts.
We'll be getting into how different extracts and cosmeceuticals play well together in the near future. For now, if an ingredient says it's "exfoliating" or "regenerating", it's probably a bad idea to pair it with something else that comes with the same adjectives. For instance, combining AHAs with papaya extract or retinoids could leave you with a very very sore face from all that peeling and exfoliating.
As for rinse off versus leave in products...this is an age old dilemma. For the most part, anything expensive that can go into a leave in product should go into a leave in product. In hair care products, for the most part you want to put those things that film form, moisturize, penetrate the hair shaft, and so on into the conditioner because you're rinsing off that shampoo and a lot of those lovely ingredients down the drain. Same for facial cleansers. I like to save my exotic ingredients for my moisturizer or toner (which I use as a moisturizer, so I leave a lot of it on my face). Having said that, there may be some value to having some of those ingredients in a rinse off product, especially if they don't rinse off (for instance, glycerin).
This is a great question and one I'll address in all the upcoming cosmeceutical posts!
Well, that's it for today. I'm still trying to catch up from my almost week of lying in bed recovering from ickiness (avoid this stomach flu - it's an eight to nine day event!) so look for a return to our regularly scheduled programming on Friday or Saturday morning!