Home Cosmetic Science Talk Formulating General Hair lotion preservative/emulsifier problems

  • Hair lotion preservative/emulsifier problems

    Posted by Marko on May 29, 2023 at 5:12 pm

    Hi to everyone. First to say, this forum is realy great discovery for me! Lot of helpfull advices for formulators.

    I am trying to formulate hair growth and antidandruff, leave on, hair lotion (so far had about 30 test with different ingredients and concentrations).


    Purified water

    Urticae folii tincture (55% ethanol)

    Rosemary essential oil

    Myrtus communis essential oil

    Tea tree essential oil

    Lavender essential oil

    Pentylene glycol




    Polysorbate 80

    Span 80

    C02 rosemary extract


    Lactic acid

    Geoguard 211

    Tetrasodium glutamate diacetate

    Citric acid

    Sodium hydroxide

    I have several issues:

    1. I wanted to use Geogard ultra as persevative but as I red, several people in disscusion here on forum claim it is not strong enough. Than I changed to Geoguard 211, but many traders mention that it is incopatibile with nonionic surfactants (I have polysorbat 80 as emulgator). What is your experience with this combination? Do you advice me to use this two substances in same product?
    Lonza has studies where they use Polysorbate 80 (0,5% conc) with Geoguard 211 in hair conditioner, and it is fine with them.


    2. I am using Dynamix mixer for emuslification, polysorbate 80 as u/v emulsifier and span 80 (antifoaming agent) but my emulsion is not stable for long time. I will put instruction “shake well before use” but could you suggest me something to improve here?

    Essential oils are 12% of the all ingredients.

    3. Looking on the ingredient table, do you have any other advice what can I improve?

    Thank you very much!

    PhilGeis replied 10 months ago 3 Members · 11 Replies
  • 11 Replies
  • ketchito

    May 29, 2023 at 9:30 pm

    Are you making the formula for your own use or for commercial purposes? If it’s for the later, you’d need to use a proven antidandruff active, especially in the USA (those actived are monographed). Now, if you want to use essential oils and depending on the amount, instead of reducing or preventing dandruff, you might cause some dandruff-like reaction (contact dermatitis) in people who are sensitive.

    For both benefits (growing hair and dandruff) you’ll have to conduct clinical trials. The first benefit would be the hardest to prove and it’d depend on your country’s regulations since besides minoxidil and finasteride (at some extent), nothing really proved to really work on hair growth.

  • PhilGeis

    May 30, 2023 at 5:47 am

    What’s your packaging?

    • Marko

      May 30, 2023 at 6:59 am

      Amber glass bottle GL18, with plastic mist sprayer cap.

      I am aware od evaporation od essential oils, so my choice was amber glass.

      • PhilGeis

        May 30, 2023 at 8:26 am

        Amber doesn’t control evaporation - perhaps oxidation. and leaching.

        For sprays, you should have a stronger system as, if present, contamination will be inhaled. Mere presence of a nonionic line Tween in formula does not mean it will neutralize but 221 is a weak preservative in any context. Perhaps phenoxyethanol?

        What is pH?

        • Marko

          May 30, 2023 at 11:59 am

          I agree that amber glass does not prevent completely evaporation, but for products which have essential oils in some % it is, in my opinion, much better option than plastic container (permeability, interactions…). Also, many manufacturers use glass as primary package material for pure essential oils.

          pH of lotion is 4,75.

          I now that parabens or phenoxyethanol is good solution for preservation but I was looking forward to use some COSMOS approved preservatives, because in pharmacy I see every day that pressures from market leaders regarding “paraben free, phenoxyethanol free, etc” cometic is rising.

          You think 1% Geoguard 221 in this formula is not enough for 2 years shelf life?

          In your opinion Geoguard 221 would not be inactivated in presence on nonionic surfactant?

          Thanks for advice about spray mist cap!

  • PhilGeis

    May 31, 2023 at 5:48 am

    Inactivation? Test it.

    COSMOS/Ecocert confines your efforts to options limited in efficacy. Your package may limit consumer contamination but magnifies risk (via inhalation) if there is contamination. What is the quality of your production - water, raw materials, sanitization, etc.? Major manufacturers work on a 3 year product life.

    To ketchito’s question - efficacy (hair growth and anti dandruff) - add safety, esp. via inhalation. How do you answer these?

    • Marko

      May 31, 2023 at 10:58 am

      Quality of materials. For all materials I have certificate with MB tests, some of them PhEUR quality, regarding dishes, before usage I apply cleaning procedures that I saw in while working in the pharma industry (water, diluted ethanol).

      Regarding package, i was thinking to replace spray mist cap with lotion pump, not just because possible contamination through inhalation, but also because I have a problem to find decent quality spray mist cap (clogging from time to time, spraying problems..).

      Exposure to essential oils can be calculated from % of every oil component in lotion, and with the volume that is applied if it is used according to label.

      I was considering to adding small amounts of xanthan gum and/or cetyl alcohol to stabilise emulsion. What is your experience with these ingredients?
      Do you think that lotion shelf life would be longer if I succeed to prevent phase separation during shelf life?

      • PhilGeis

        June 14, 2023 at 5:27 am

        Sorry Marko - I missed your reply.

        I’m speaking 1) of micro quality - including that of water and 2) of safety of ingredients inhaled.

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