Home Cosmetic Science Talk Formulating ‘Grime’ appeared on cream

  • ‘Grime’ appeared on cream

    Posted by Danger on January 8, 2019 at 8:36 am

    Dear all,

    I have problem with this formula:

    Water phase:
    Aqua
    Xanthan gum 1%
    Propylen glycol 2%
    Glycerine 2%
    Phenoxyethanol 1%

    Oil phase:
    Emulium delta (Cetyl alcohol, Glyceryl stearate, PEG-75 stearate, Ceteth-20, Steareth-20) 5%
    Stearyl alcohol 2%
    Caprylic/ Capric Triglyceride 3%
    Coco caprylate 4%
    Cetearyl isononanoate 3%
    Silicon oil 5%

    Hot process.

    Personally, the formula forms good texture, spreadibility, and shining cream. But when applied on skin, dried for a while, and then rubbed gently — then (I called it) ‘grime’ appeared, something like a small layer detached from skin .. I hope you all understand what I mean.. 

    I noticed that if I eliminate the Silicon oil, then there will be no ‘grime’. But the spreadibility becomes bad and look like ‘soap’ when rubbed on skin.

    What happens actually ? i guess the silicon oil is incompatible with xanthan gum. Any suggests what ingredients to replace silicon oil?

    Thanks a lot

    Danger replied 5 years, 9 months ago 5 Members · 8 Replies
  • 8 Replies
  • gld010

    Member
    January 8, 2019 at 2:18 pm

    I think that “grime” is from the high amount of Xanthan gum- it’s forming a layer as it dries and will start “pilling” and peeling off your skin when rubbed. Xanthan gum is usually used at 0.5% or less. I can’t comment on why it’s doing it only in the presence of dimethicone though.

    “But the spreadibility becomes bad and look like ‘soap’ when rubbed on skin.” That is quite literally called “soaping” and dimethicone is the best way to eliminate it. You can also try something like isoamyl laurate (dermofeel sensolv) but it doesn’t always work to get rid of soaping.

  • chemicalmatt

    Member
    January 8, 2019 at 10:17 pm

    Agree with gld010: xanthan is “pilling” upon rubdown on the skin. Get rid of it, you don’t need it. You DO need a preservative, though. Phenoxyethanol is NOT a preservative by itself. 

  • Danger

    Member
    January 9, 2019 at 1:44 am

    I had made several trials with xanthan gum 1% and there were no ‘grime’ or ‘peeliing off’ . It only occurs if silicon oil exist. I have choices to eliminate xanthan gum or silicon oil and still working on. I just wondering any theory about this ‘grime’.
    I prefer use xanthan gum so maybe you have alternative material to replace silicon oil ? 

  • Microformulation

    Member
    January 9, 2019 at 3:47 am
    Could you better define “silicone oil?”
  • Danger

    Member
    January 9, 2019 at 4:22 am

    I use Silicon Oil (Dimethicone) 100 cps

  • Microformulation

    Member
    January 9, 2019 at 3:14 pm
    Ok, then the INCI would be Dimethicone.
  • jeromeinthehouse

    Member
    January 9, 2019 at 6:23 pm

    i would try a alkane with high boiling point

  • Danger

    Member
    February 6, 2019 at 9:01 am

    Dear all, 

    Thank you for all the opinions. As an update, I have succeed in eliminating the grime, by reducing xanthan gum and replace dimethicone with alkane. Thanks @gld010  @jeromeinthehouse. So I had found suitable formula for my cream BASE. I hope with this cream base I can get some products by just adding up other active ingredients (powder/liquid) in it.

    But when I add arbutin powder 5% and tranexamic acid powder 3%, the grime appeared again. I also tried to solubilize the powder in water, but the grime still appeared. Why this happened ? Did I missed something? Thank you all

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