• Formulating

  Zinc Pyrithione and Salicylic Acid React in Surfactant System

  Posted by Carrie on November 29, 2022 at 10:37 pm

  Hello! I have seen in that past, and am seeing again a surfactant formulation that contains Zinc Pyrithione and Salicylic Acid turning purple when in the presence of stainless steel kettles and spatulas. The surfactants in the system are Sodium C14-16 Olefin Sulfonate, Cocamidopropylamine Oxide and Cocamidopropyl Hydroxysultaine. Can anyone help with this phenomonan?? 

  PhilGeis replied 1 year, 12 months ago 3 Members · 2 Replies
• 2 Replies

• 

  ozgirl

  Member

  November 30, 2022 at 12:15 am

  Zinc Pyrithione turns blue in the presence of ferric ions.

  The background section of this patent has more information. https://patents.google.com/patent/US5883154A/en

• 

  PhilGeis

  Member

  November 30, 2022 at 1:59 pm

  This is quite predictable.  With or without the ferric ion, these are not compatible.  For the same reason, folks don’t formulate with ZPT antidandruff products with EDTA.

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