-
Precipitation with Sodium Cocoyl Isethionate in a makeup remover formulation
Hello everyone,
Can someone help me with the following issue please?
I prepared a make up formulation containing Sodium cocoyl isethionate (2%) with sophororlipids (3.6%) and my formulation precipitated overnight. Does someone have a guess what might be the cause and which direction shall I take? I would appreciate your suggestions.
Thank you in advance
Regards
-
8 Replies
-
Are those ingredients the only ones in your formula? Where they completely dissolved at the start? What’s the pH of your solution?
-
No. I also used humectants (glycerin, propylene glycol) and xanthan gum. pH is 5.65. It wasnt easy to dissolve so I heated the water to 50 degrees and then SCI was dissolved. The solution was translucent though.
-
-
Sodium Cocoyl Isethionate is not really the best option for clear liquid systems because it is not very soluble. What you are seeing is probably it cooling and precipitating. It can be stabilised but there are much better options out there.
If you want to stick with isethionates, try using Sodium Lauroyl Methyl Isethionate (Iselux) or try a different surfactant.
-
Thank you so much for your answers. Since I only have this type of isethionate in the lab. But I read that APGs can help with their solubility in water so I tried Lauryl glucoside and it could dissolve and make a transparent clear liquid. However, I am curious about its stability.
For the stability, do we usually conduct 7-days accelerated test at 50 degrees in addition to 3 months stability at RT and 45degrees?
-
I believe Cocamidopropyl Betaine also helps to improve SCI solubility in water. Try to add a little, 🙂 Good luck.
-
Hii Paprik, thank you for the recommendation. I tried CAPB also, but precipitation occurred. Had no luck with it. Thanks though.
-
-
I agree with the earlier comments especially from ozgirl, Iselux is a fantastic alternative, although it is in a cost league of it’s own. pH is also important for SCI and doesn’t like to be below 6. I would reduce the SCI to 1% and replace it with something else that you have - 2% of 50% glucoside for 1% SCI.
-
Thank you @richard I tried your recommendation. Solution is quite clear, no precipitation. I will do the makeup removal efficacy soon. Do you have any suggestions on the related tests for makeup remover formulation?
-
Log in to reply.