Home Cosmetic Science Talk Formulating Black waxy residue from lotion

  • Black waxy residue from lotion

    Posted by Doaneventry on March 1, 2017 at 2:27 am

    I made a cream. After really rubbing in the cream. A black waxy ball residue coalesces. I can’t figure out which ingredient is doing this.

    Ingredient list:

    Water, IPM, Glycerin, Carpylic/carpric Triglyceride, Cetyl Alcohol, Stearic Acid triple beads, (Sodium polyacrylate, hydrogenated polydecene, trideceth-6 Mixture), (glyceryl monostearate, PEG-100 Stearate flakes), Sunflower Seed oil. 

    I am very new to formulating. Any guidance would help. Thank you

    belassi replied 7 years ago 4 Members · 12 Replies
  • 12 Replies
  • belassi

    Member
    March 1, 2017 at 3:06 am

    To begin, please list the formula properly with percentages.
    EG
    Water 67%
    Isopropyl Myristate 5%
    etc

  • chemist77

    Member
    March 1, 2017 at 3:32 am

    Is that that the complete list as I don’t see a preservative there. That mixture you are using at times shows incompatibility in presence of electrolytes, cationics and anything which might harm the polymer. 

  • johnb

    Member
    March 1, 2017 at 7:50 am

    It is most likely the emulsion breaking and coagulating on the skin. The blackness is dirt collected during the emulsion breaking.

  • Doaneventry

    Member
    March 1, 2017 at 5:34 pm

    Water, 70.0%
    Glycerin, 8.0 %
    Caprylic/Capric Triglyceride, 5.0%
    IPM, 2.0%
    Cetyl Alcohol, 3.0%
    Stearic Acid triple beads, 2.0 %
    (Sodium polyacrylate60%, hydrogenated polydecene35%, trideceth-6 5% mixture), 2.40%
    Disodium EDTA, 0.10%
    Glyceryl monostearate, 0.5%
    PEG-100 Stearate, 0.5%
    SunFlower seed oil, 4.0%
    Benzyl Alcohol, Dehydroacetic Acid mixture, 0.4%
    Fragrance, 1.0%

    ph ~ 6.5

  • chemist77

    Member
    March 1, 2017 at 5:42 pm

    Try knocking out EDTA and if I were you I would check my preservative too. Nothing else seems out of place there if I am not mistaken. 

  • Doaneventry

    Member
    March 1, 2017 at 5:49 pm

    I made a run without EDTA, and then Added EDTA because I thought I had an electrolyte problem. I do not believe EDTA is the problem.

  • Doaneventry

    Member
    March 1, 2017 at 5:51 pm

    Do I need higher levels of my emulsifiers?

  • belassi

    Member
    March 1, 2017 at 6:27 pm

    Do I need higher levels of my emulsifiers?
    Yes, absolutely.

  • Doaneventry

    Member
    March 2, 2017 at 8:38 pm

    @Belassi @johnb @Chemist77
    I tried increasing the emulsifier levels to 3% and then 6%. and the black residue still comes out after rubbing in the cream. 

  • belassi

    Member
    March 2, 2017 at 9:06 pm

    You’ve got about 16% lipids in there. I would be using around 6% glyceryl stearate and 4% PEG-7 GC, but I’d have to do the HLB calcs first.

  • Doaneventry

    Member
    March 2, 2017 at 9:53 pm

    @Belassi
    HLB value of oil phase is 9.53. I am really unable to do much with my emulsifiers. It’s actually a  blend of 50% glyceryl stearate and 50% peg-100 stearate flakes, whose hlb together is 11.

    I tried to adjust the ingredients amount to be close to 11 as possible while trying to make the lotion look and a certain way per client request. 

    Does it matter that much if the hlb value of emulsifiers is off by 1 or 2? 

  • belassi

    Member
    March 2, 2017 at 11:57 pm

    Does it matter that much if the hlb value of emulsifiers is off by 1 or 2? 
    No. Just keep increasing the emulsifier until the system works. Also you MUST use high shear.

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