Thanks very much, it does seem like we should probably include all of these. Do you know what the correct ratios are between the Pg / ethanol / transcutol / polysorbate 80 / ascorbyl palminate ?
Check out "Example 4" in this patent:
https://patents.google.com/patent/EP3108879A1
Grams per 100g:
Cortexolone-17α-propionate 5.00
Diethylene glycol monoethyl ether 31.50
Alcohol (Ethanol) 31.50
Ascorbyl palmitate 0.50
Polysorbate 80 0.10
Propylene glycol 31.40
Also, note that these are mass ratios. Volumetric ratios will be slightly different because of different densities:
Ethanol 95% - 0.816 g/cm³
Diethylene glycol monoethyl ether (transcutol) 0.99 g/cm³
Propylene glycol 1.04 g/cm³
For this reason volumetric ratios will be closer to 4/3/3 (eth/pg/transcutol). I don't know if it matters though.
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