I've made a formulation about depilatory cream. The ingredients are:
Water adj to 100%
PARAFFINUM LIQUIDUM 5
Cetyl alcohol 3.5
Cestearyl alcohol 3
ceteareth 20 3.5
NaOH adj to pH = 12
Ca thioglycolate 8 (active 50%)
Perfume 0.3 - 0.4
and i have some problem about the stability of that cream. The cream will turn from white to yellow in the surface and the texture of the cream will unstable about 4 to 5 week in Accelerated test conditions.
I don't have any idea to increase the stable time of this formulation. Please help me!!!