Cosmetic Science Talk

Cosmetic Science discussion form. For people who want for formulate cosmetics and get advice from other formulators around the world.

Home Cosmetic Science Talk Formulating glycerin and preservatives.

  • glycerin and preservatives.

    Posted by lipstickgirl on March 26, 2016 at 9:22 pm

    I have a question regarding a pressing medium for cosmetic glitters.

    I am using 90% isopropyl alcohol at 75% of the formula, glycerin at 25% of the formula then adding cap 5 at 1% of the total weight of the liquid.

    Cap 5:
    Phenoxyethanol, Caprylyl Glycol, Potassium Sorbate, Hexylene Glycol. The Caprylyl and Hexylene

    Is this adequate to preserve the finished product from bacteria & mold once it is mixed with cosmetic glitter and pressed?

    lipstickgirl replied 6 years, 10 months ago 3 Members · 4 Replies
  • 4 Replies
  • lipstickgirl

    Member
    March 26, 2016 at 9:44 pm

    Is glycerin a problem in this formula considering that it is a humectant. Will it cause bacteria in the finished product regardless of preservative being added?

  • DesertInBloomCosmeticsLab

    Member
    March 26, 2016 at 10:00 pm

    @lipstickgirl:

    Actually, glycerin is a polyol … it has 3 hydroxyl groups. instead of 2 (glycol).  No, glycerin will not facilitate the growth of bacteria in a finished product.
  • lipstickgirl

    Member
    March 26, 2016 at 10:04 pm

    Thank you Mark. So do you think this is a safe pressing medium/binder for pressing cosmetic glitter?

  • Bill_Toge

    Member
    March 26, 2016 at 10:31 pm

    you’ve got 67.5% w/w isopropyl alcohol in your formula, so there’s no chance of anything even surviving, let alone growing in there; in my view, your existing preservative is unnecessary

  • lipstickgirl

    Member
    March 26, 2016 at 10:43 pm

    Thanks Bill! I guess my primary concern was the water from the alcohol and the gylcerin drawing moisture into the finished product casing bacteria and fungus to grow.