Thanks very much @Bobzchemist for a very interesting point of view. Really got me to thinking. I will of course follow your tips and try this out.
I talked with the distributor about the emulsifiers. I quote “… usually soaping is due to excessive use of fatty alcohols and sometimes fatty acids. Any time that these are present at more than 3% total it requires the addition of advanced chemistry to avoid the soaping.”
That’s the other tip: ALWAYS question your suppliers about their raw materials. Of course we must test and run the knock-out series but the supplier must know or at least be interested in knowing the ingredient. I always question and ask them to run some testes in parallel. This way we learn together. Sometimes when there’s time to wait and I have other profects with narrower deadlines, I even demand the information on the supplier and keep going with my taks. There was only once I had issue with that because the supplier didn’t do anything. And then I replaced their ingredient. Now I can trust all my suppliers on this support.
January 23, 2014 at 3:00 pm
After following a HLB calculator, I managed to use Olivem 1000 at 2,5% and Glyceryl Stearate 1,4%. This worked very well to form a nice white cream, not very runny. In the final formula I would use Xanthan Gum to thicken and stabilize water phrase. So, when I used fatty alcohols and fatty acids under 3%, I managed to cut down on the soaping and lack of absorbing of the formula.
This leads to further questions. How can I thicken the cream without using fatty acids or fatty alcohols? Is beeswax a fatty alcohol? What about Prehydrated Gum Arabic? Can floral waxes be used? For example Rosa multiflora (rose) flower wax, witch is a solid creamy wax?
>How can I thicken the cream without using fatty acids or fatty alcohols?
Creams can be thickened in a number of ways. One of the easier ways is to increase the viscosity (thickness) of the creams outer, continuous phase. A thicker continuous phase also increases stability, by making it harder for the oil micelles to coalesce.
You can use natural gums (xanthan, guar, locust bean, Gum Arabic, maybe the cellulosics) to thicken your water phase, or you can use mineral products (veegum, silica, etc.) I’m leaving out the polymeric and associative thickeners, since you can’t use those.
>Is beeswax a fatty alcohol?
Short answer: No
Longer answer: You really should look this up yourself, but…
“An approximate chemical formula for beeswax is C15H31COOC30H61. Its main components are palmitate, palmitoleate, and oleate esters of long-chain (30-32 carbons) aliphatic alcohols, with the ratio of triacontanyl palmitate CH3(CH2)29O-CO-(CH2)14CH3 to cerotic acid CH3(CH2)24COOH, the two principal components, being 6:1″ http://en.wikipedia.org/wiki/Beeswax
“Fatty alcohols (or long-chain alcohols) are usually high-molecular-weight, straight-chain primary alcohols, but can also range from as few as 4-6 carbons to as many as 22-26, derived from natural fats and oils. The precise chain length varies with the source. Some commercially important fatty alcohols are lauryl, stearyl, and oleyl alcohols. They are colourless waxy solids, although impure samples may appear yellow. Fatty alcohols usually have an even number of carbon atoms and a single alcohol group (-OH) attached to the terminal carbon. Some are unsaturated and some are branched.” http://en.wikipedia.org/wiki/Fatty_alcohol
” a fatty acid is a carboxylic acid with a long aliphatic tail (chain), which is either saturated or unsaturated. Most naturally occurring fatty acids have a chain of an even number of carbon atoms, from 4 to 28. Fatty acids are usually derived from triglycerides or phospholipids.” http://en.wikipedia.org/wiki/Fatty_acid
>What about Prehydrated Gum Arabic?
What about it? What do you need to know?
>Can floral waxes be used?
Why would you think they couldn’t be used? Specifically, what properties does the wax have that would lead you to suspect that it would not be appropriate for this use? Really, you can use anything you like that’s cosmetic grade. The question is what effects you’ll get. Adding waxes to an oil phase is one of the other ways of increasing viscosity. This method does not increase stability by much, if at all, which is why I didn’t suggest it first.
>For example Rosa multiflora (rose) flower wax, witch is a solid creamy wax?
Try it, see what happens. Enjoying experimentation and having a certain amount of inquisitiveness are key characteristics for a cosmetic chemist. If you don’t like to get in the lab and tinker, just to see what will happen, you will probably not be all that happy in your career.