Bluish Appearance

When formulating a high SPF Sunscreen with only Zinc Oxide and TiO2, can someone recommend how to get rid of the bluish appearance when applying it on the skin.

Comments

  • BobzchemistBobzchemist Member, PCF student
    Use a small bit of yellow and/or red iron oxide?

    Why is that bluish look a problem?
    Robert Zonis, Sr. Formulation Chemist, Beaumont Products "All opinions and comments expressed are my own, have no relation to Beaumont Products, are fully copyrighted, and may not be used without written permission."
  • The formula is a water in silicone system. Do you have any recommendation about how to add Boron Nitride into the formula? Add to the oil phase or add at the end?

    By the way, do you think different procedures will impact the bluish appearance or not, for example, how to add the Zno and TiO2, with mixer or with silverson? Both of them are coated.

  • Regarding your question on why bluish color is an issue..We are only use ZnO and TiO2 as the UV filters targeting SPF value 55. The powder’s use level are very high, and appears to cause just too much bluish and white appearance on the skin. It's just an unfavorable look.
  • johnbjohnb Member, Professional Chemist
    Are you using microfine/nanofine particle size ZnO and TiO2
  • BobzchemistBobzchemist Member, PCF student
    So, I misunderstood your question a bit. You don't want to make the bluish-white look into a yellowish-white look, you want the entire white look to go away. That means that you will need to use a different brand/grade of TiO2 and/or ZnO. 

    The only way to do this is to get smaller, more tightly-controlled particle sizes. Processing will not affect this at all. You need to have particles that are sized small enough not to reflect visible light, but are large enough to reflect UV light. It may take some time/experimentation to find, but there are products that will do this.

    For a SPF 55, you probably won't have room for anything like Boron Nitride, which is OK, because it would only make the problem worse anyway.
    Robert Zonis, Sr. Formulation Chemist, Beaumont Products "All opinions and comments expressed are my own, have no relation to Beaumont Products, are fully copyrighted, and may not be used without written permission."
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