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Evaluate ingredients and method for Face Cream with Perfect C and Matrixyl 3000
I did a test to check stability with minimal ingredients to see if light cream would form with phases heated to less than 60 degrees and then cool down to 45 degrees before using a stick blender to emulsify and cream formed and stable and did not split.
Basic formula was :
Test first with Water , Sepimax Zen and no extras 100.00
Heated water phase - Heat to 50 Degrees %
Distilled water 74.00%
EDTA 0.25%
Sepimax Zen - Thickener 0.30%
Total Water Phase 74.55%
Heated oil phase (can have 30% Oil with this emulsifyer
Note only heat Oil until 50 degrees and let cool down below 45 before emulsifying
Lipomulse Emulsifying Wax (Non-Ionic) INCI : Cetearyl Alcohol, Glyceryl Stearate, PEG-40 Stearate, Ceteareth-20 4.00%
Cetyl Alcohol 2.50%
MCT Oil to Test 18.25%
Total Oil Phase 24.75%
Cooldown
Preservative INCI : Liquid Germall Plus - Propylene Glycol (and) Diazolidinyl Urea (and) Iodopropynyl Butylcarbamate. 0.50%
Vit E (70% tocopherols) 0.20%
Total Cooldown Phase below 40 Degrees C 0.70%
Total 100.00%

I want to make a cream with the following ingredients and also wonder if I could include Panthenol Vitamin B5 powder 2% in the water phase ( I would reduce Water % to include the Panthenol so total formula 100% if no contradictions with using Perfect C etc) - The proposed formula is:
Face Cream - with Perfect C and Matrixyl 3000 100.00
Heated water phase - Heat to 50 Degrees %
Distilled water 63.10%
Pentylene glycol (Oil and Water Soluble) 2.00%
EDTA 0.20%
Sepimax Zen - Thickener 0.30%
Total Water Phase 65.60%
Heated oil phase (can have 30% Oil with this emulsifyer
Note only heat Oil until <55 degrees and let cool down below 45 degrees before adding Perfect C
Lipomulse Emulsifying Wax (Non-Ionic) INCI : Cetearyl Alcohol, Glyceryl Stearate, PEG-40 Stearate, Ceteareth-20 4.00%
Cetyl Alcohol 2.50%
Squalane 5.50%
Coco-Caprylate 5.00%
Isoamyl Laurate 3.00%
Perfect-C™ (Ascorbyl Tetraisopalmitate) 4.00%
Total Oil Phase 24.00%
Cooldown
Preservative INCI : Liquid Germall - Propylene Glycol (and) Diazolidinyl Urea (and) Iodopropynyl Butylcarbamate. 0.50%
Vit E (70% tocopherols) 0.40%
 Ethoxydiglycol (EDG) 2.50%
Ferulic Acid 1.00%
Matrixyl™ 3000 3.00%
Double Hyaluron Liquid 3.00%
Total Cooldown Phase below 40 Degrees C 10.40%
Total 100.00%
I planned adding Perfect C in heated oil phase when oil phase is below 45 degrees or would I be better off adding in Cooldown once emulsions is formed with the other cooldown ingredients? Thanks for your advice.