• Formulating

  Liquid foundation with coated powders

  Posted by Shams on February 15, 2022 at 2:13 am

  Hi everyone

  I am formulating a liquid foundation o/w
  I am using a zinc oxide dispersion(in Cocoaprylate) and uncoated iron oxides.
  I used to make it using uncoated TiO2 and I never had an issue.
  Now I want to swap the uncoated TiO2 with coated TiO2 with jojoba esters

  I tried 3 different protocols and in the 3 it seems the TiO2 can’t be dipersed and as if it is phasing out:
  1- I added the coated TiO2 at the end after the emulaion to minimise homogensing so I don’t break the coat
  2-I pregrinded it with the uncoated colored oxides
  3-I pre wetted it in oils and added it in the oil phase from the begining

  None worked.

  Any ideas where is the problem

  TIA

  chemicalmatt replied 2 years, 2 months ago 3 Members · 4 Replies
• 4 Replies

• 

  evchem2

  Member

  February 17, 2022 at 4:36 pm

  So you’re using both zinc oxide and titanium? What’s your final product pH, how fast do you see the issue occurring?  

• 

  Shams

  Member

  February 17, 2022 at 10:44 pm

  @evchem2 yes I am using both.
  pH is between 7.5 - 8
  I see this issue while cooling down the emulsion.

• 

  evchem2

  Member

  February 18, 2022 at 8:25 pm

  Not exactly the same but Croda’s guidance on inorganic sunscreens may help you here. 

• 

  chemicalmatt

  Member

  February 24, 2022 at 4:01 pm

  Hard to help without knowing the constituents of your “liquid foundation o/w”. With all those minerals the easiest outcome would be to reformulate as an invert w/o or w/Si system. That’s the method of choice for these things. 

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