Home Cosmetic Science Talk Formulating Sunscreen with Avobenzone

  • Sunscreen with Avobenzone

    Posted by krupabrahmbhatt on January 24, 2014 at 8:42 am

    Hi Everyone, 

    I am making a sunscreen with Avobenzone and Octocrylene.. and about 4% total oil phase. My formula is mainly water and carbomer with 10% Alcohol. 
    I am having trouble making the final product white — it always turns out slightly yellow. Would you know how I can achieve the white color? 
    Also, I know its not an iron issue - added 0.2% chelating agent. I have tried increasing the oil phase a little bit but that doesnt seem to help either… 
    Thanks in advance for all your help/advice! :)
    krupabrahmbhatt replied 10 years, 6 months ago 3 Members · 5 Replies
  • 5 Replies
  • Chemist77

    Member
    January 24, 2014 at 9:57 am

    oops my bad, didnt read properly. How about replacing alcohol partially with cyclomethicone, cutting down on alcohol may increase the milkiness and at the same time cyclomethicone would aid in increasing the milky appearance. Dont need to change a lot in this, if doesnt work out then try other better options. Cyclomethicone or any light ester wouldnt feel heavy at the same time. Recently I came across Isoamyl Laurate and it had the lightest feel on skin. If I recollect from previous posts by Chemicalmatt he once mentioned c12-15 alkyl benzoate as one of the best emollient esters and at the same time a very good aid as a solubilizer. Correct me if i m totally wayward on this.

  • Bobzchemist

    Member
    January 24, 2014 at 10:03 am

    1) The easy way would be to add Titanium dioxide.

    2) The smaller your oil phase droplets are, the whiter your emulsion will be. How can you improve your emulsion?
    3) You didn’t even mention an emulsifier - what are you using to keep this emulsion stable?
    4) You really need a stabilizer for the avobenzone.
  • krupabrahmbhatt

    Member
    January 24, 2014 at 10:15 am

    I am using Cetyl Alcohol at 2 % and Isostearyl Alcohol as an emollient.. I didnt think i needed more emulsifier since i am trying to make the overall feel as less greasy as possible… 

    Oh and I also have 1% of Ganex 220 V in the oil phase..
    Should I add some more emulsifier you think? 
  • krupabrahmbhatt

    Member
    January 24, 2014 at 10:16 am

    @bobzchemist Doesnt octocrylene help solubilize/stabilize avobenzone?? I have 5% octocrylene and 2% avobenzone..

  • krupabrahmbhatt

    Member
    January 24, 2014 at 1:18 pm

    @bobzchemist and @milliachemist you guys are awesome! I used 2% Arlacel 165: Glyceryl Stearate and PEG-100 Stearate with 1% Promulgen D: Cetearyl Alcohol and Ceteth-20..instead of cetyl alcohol and it worked!!! 

    My formula is white :) Thanks guys!

Log in to reply.