Anti-Perspirant precipitate

My 20% aluminum chlorohydate AP cream is still gritty after I left out the allantoin. So it must be aluminum chlorohydrate precipitate. Can someone please help me with this problem?
I read on MakingCosmetics that it is soluble in cold water, but the quantity (even half of it) is too large to put in the cool down phase. Supplier says it can be put in hot water phase.
Should I lower the oil phase, so there is more water for it to stay dissolved in? 

A ) 
Water, distilled & deionized ad 100
4% Glycerin
40% Locron L (50/50 water, Al2Cl(OH)5)

B )
5% GMS + PEG-100 Stearate (I tried GMS + ceteareth-20 earlier)
2% Polyglyceryl-3 Stearate
3% Cetearyl Alcohol
4% Triethyl Citrate
2% Dimethicon 350 cSt.
4% IPM
1% Hydrogenated Vegetable Oil

B1 )
0,9% Sepimax Zen

C )
1% cyclo D5
2% Vari Stan PE (Garcinia Mangostana Peel Extract (and) Propanediol)
1% Phenonip (I have run out, next experiment I will use Liquid Germall Plus or Germaben II)

The viscosity is perfect. The only problem is the grittiness.

Much obliged!! :+1:


  • Chemist77Chemist77 Member, PCF student
    Although I haven’t used this Sepimax Zen but the literature clearly mentions salt tolerance of upto 10% and you are 20% with that Locron. Maybe you can have a look at it.
  • DoreenDoreen Member
    edited December 2018
    Viscosity is perfect, so I don't think the Zen is an issue.
    I started with 1,5% Zen because of the salt tolerance, but it ended up in a paste!

    I am beginning to doubt if the product is heat stable and the precipitate maybe a degradation product, an insoluble aluminum compound or so.
  • Chemist77Chemist77 Member, PCF student
    Just to make sure, either reduce the Locron dosage or try knocking out Sepimax Zen to see if that grittiness persists. It will confirm your perception of insoluble salt. 
  • DoreenDoreen Member
    edited December 2018
    Thanks for your input!
    More evidence regarding heat instability.
    Too bad this document doesn't say from what temperature, but I've got to find a way around that heated water phase. I don't know any cold process emulsifiers that can withstand that much electrolytes.

    'If heated, it releases water and hydrochloric acid. Rising temperatures lead in turn to the formation of aluminum hydroxide gels, γ-aluminum oxide and finally α-aluminum oxide (corundum).'

    Corundum? Am I making gems? :joy:
  • Chemist77Chemist77 Member, PCF student
    Check if it has ruby and sapphires ??
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