Home Cosmetic Science Talk Formulating urea ointment

  • urea ointment

    Posted by jrnb on November 27, 2017 at 3:55 pm

    hi, we try to make a 40% urea product in oil/fat base. but the urea does not disolve well enough.We have made a 40% waterbased urea cream and it looks good but in use it is not usable as it chrystalizes to 100% urea on the skin. Any tips are welcome. I am not a formulator but the owner of a EU based cosmetic company.My formulator is stuck with this project. 

    Dorsaf replied 2 weeks, 5 days ago 8 Members · 13 Replies
  • 13 Replies
  • belassi

    Member
    November 27, 2017 at 4:46 pm

    My formulator is stuck with this project. 
    40% Urea? And you wonder why the formulator is having trouble?

  • bobzchemist

    Member
    November 27, 2017 at 4:49 pm

    Can’t you just grind the urea into the anhydrous base? It’s so polar that it’s not really soluble in anything other than water or alcohol.

  • chemicalmatt

    Member
    November 27, 2017 at 5:19 pm

    jrnb, this project was simply a bad idea. Scrap it and move on. Like Bob said, urea is water-soluble only, and it does nothing to soften skin in the solid state form.

  • jrnb

    Member
    November 28, 2017 at 2:32 pm

    There are brands already making this product and 40% is a well known formulation for nail removal product. So it must be possible. I will discuss the grinding. Thank you!  

  • bobzchemist

    Member
    November 28, 2017 at 2:54 pm

    Using a 3-roll mill is probably your best choice. Other grinding methods do not cope well with high-viscosity products like ointments.

  • belassi

    Member
    November 28, 2017 at 3:45 pm

    40% is a well known formulation for nail removal product.
    WHAT? Please explain!

  • bobzchemist

    Member
    November 28, 2017 at 7:16 pm
  • DRBOB@VERDIENT.BIZ

    Member
    November 28, 2017 at 9:56 pm

    @jrnb You should be able to triturate with glycerine for water base using a lot of elbow grease and 5-10 % glycerine to avoid crystallization on skin.I don’t know what oils you are using but you should be able to do the same with lanolin or petrolatum.

  • em88

    Member
    November 29, 2017 at 7:53 am

    The urea must be in fine particles and I think Merck can provide it. 
    You can dissolve urea in a mixture of glycerol and alcohol which can be incorporated in the simple ointment base (10% lanolin, 90% petrolatum) 

    • Dorsaf

      Member
      February 12, 2024 at 10:27 am

      Without using an emulsifier?? And wich amount of glycerine we use,what about preservatif?? I m dealing with the same issue

      • microformulation

        Member
        February 12, 2024 at 12:01 pm

        A. Lanolin is being used as the W/O emulsifier here. B. There is no absolute level of Glycerin that predictably self-preserves. Glycerin can be used as an adjunct as it decreases free water but free water needs to be tested for. C. This is a very low-water product as it is a W/O emulsion. Challenge Testing would still likely be performed. https://cosmetics.specialchem.com/inci-ingredients/lanolin

        • Dorsaf

          Member
          February 13, 2024 at 11:44 pm

          Thanks a lot for your answer, i think i would refer to add a preservative, may be paraben complex?? Another question please,if we are solublising the urea in glycerine,then the aqueous phase will be 45%, or we will just considering the amount of glycerine?? Im beginner 😁

  • jrnb

    Member
    November 29, 2017 at 9:33 am

    This is very helpfull. Thanks. 

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