Home Cosmetic Science Talk Formulating Skin Body wash - unwanted sensorial

  • Body wash - unwanted sensorial

    Posted by Belassi on June 15, 2017 at 11:16 pm

    I’ve been experimenting recently with formulae for shower body wash systems, trying to compare different surfactants. My actual product is based on Plantaren APB (ammonium based) which is pretty good but I can still just about detect this effect.
    For instance this reference formula using the usual SLS combination:
    SLS 15%, SLES (20Mol) 26%, CAPB 6%, glycerine 3% Q/S water.
    This when applied to the skin in the shower gives an unpleasant “heating” sensation as if it’s warming up as applied.
    Now, I know that laundry detergent heats up when you add water so I did an experiment to see if indeed the temperature changed when I added some of the formula at 30C to water at 30C (room temp) and there was no change at all. So I assume that this sensation of heating is actually skin irritation.
    I’m going to try a couple of sulphate free formulae next.
    Your thoughts please?

    Belassi replied 6 years, 3 months ago 3 Members · 5 Replies
  • 5 Replies

    June 16, 2017 at 4:01 am

    Should show redness if irritation.Are those high percentages active?

  • Belassi

    June 16, 2017 at 4:15 am

    No, as supplied. No redness but the sensation is unpleasant.

  • johnb

    June 16, 2017 at 7:57 am

    This could be an osmotic effect where the (relatively) high concentration of surfactant is drawing moisture from the skin. I doubt it is irritation in this instance as the sensation would be longer lasting.


    June 16, 2017 at 3:20 pm

    @Belassi you could do an overnight occlusive patch test or 48HR and see if redness developes.I know 5%  active SLS alone  will give a reaction.

  • Belassi

    June 16, 2017 at 4:41 pm

    Excellent idea DrBob, I will do that. Thank you.

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