Emulsion problems

DoreenDoreen Member
edited May 2018 in Formulating
I don't know the correct English word for it, but sometimes I have that creams get a bit 'soft grainy' on the skin when you try to apply a second layer. What could be the cause for this? Fatty alcohols? Also if you add a thick layer, it happens too. (It doesn't happen when I apply a single, thin, layer)

Here's one of my O/W formulas that has this effect:

A ) 
Water distilled + deionized ad 100
0.1% Dinatrium EDTA
1.5% Allantoin
2.5% Betaine (trimethylglycine)
2.0% Niacinamide
1.0% Dipotassium glycyrrhizinate
0.5% Phenonip P4
0.6% Glyceryl Caprylate
2.0% dl-Panthenol

B )
3.0% Glyceryl Stearate Citrate
2.0% Polyglyceryl-3 Stearate
1.5% Behenyl Alcohol
2.0% Shea Butter
5.0% Camellia Japonica Oil
7.0% Isoamyl Laurate
0.5% Hydrogenated Vegetable Oil
0.5% Phenonip P4
5.0% Squalane (derived from olives)

B1 )
0.8% Sepimax Zen

C )
0.4% Tambourissa Trichophylla Leaf Extract (powder)
1.0% Embelia Extract (Water, Glycerin, Embelia Concinna Leaf Extract)
0.2% Phytrox LTR15-IP (Lecithins, Ascorbyl Palmitate, Tocopherol, Rosmarinus Officinalis Extract, Helianthus Annuus (Sunflower) Seed Oil)
1.0% Cyclopentasiloxane
3.0% Prodhyactif Softening (Aqua, Propylene Glycol, Calendula Officinalis Flower Extract, Anthemis Nobilis Flower Extract, Tilia Vulgaris Flower Extract, Centaurea Cyanus Flower, Chamomilla Recutita (Matricaria) Flower Extract, Hypericum Perforatum Flower/Leaf/Stem Extract)
0.2% α-Bisabolol (natural)
0.1% Fragrance

pH without adjustment is 5.32
It looks a bit like a BB cream, its light beige (colour mostly due to the Tambourissa extract), it's a nice, velvety soft, rich creamy emulsion.
Only disadvantage is problem mentioned above.

Edit: I just realised that I've used betaine and allantoin in a slight acidic emulsion with an anionic emulsifier. Betaine and allantoin are amphoteric, right? So these are cationic in acidic conditions... Could this have contributed to the problem more or less?

Comments

  • GuntherGunther Member
    Wow that's a really long list of ingredients
    What's the water % typically used?
    Why not sharply lower all oil-solubles to make it lighter?
  • DoreenDoreen Member
    edited May 2018
    It's supposed to be rich, with a high oil phase. (It's for own use).

    Would you have any idea what might be the cause for the 'soft grainy particle' problem? (It's impossible (for me) to find the right word in English). It's not like soaping, it's different. Or do you think the high oil phase/content has to do with the problem?
    It's comparable to if you have put on a moisturizer that doesn't go along with the foundation you use afterwards.
  • GuntherGunther Member
    edited May 2018
    if it's grainy it might be from particles coming out of solution as it dries.
    Most likely water evaporates first, leaving water-soluble, but oil-insoluble compounds precipitating as fine powder.

    While I'm biased against anything oily or greasy
    you can try with fewer oils to see if it works, as you stated that single, thin layers work fine.

    You can also try knocking out (removing) all water soluble ingredients except emulsifiers and solubilizers.
    If it improves then the problem it's in the water phase
    if it doesn't then the problem it's in the oil phase.
  • MicroformulationMicroformulation Member, Professional Chemist
    1.5% Allantoin is a lot to try and solubulize and in the US at least, above the allowable Cosmetic levels. That could be your culprit. I have seen this exact issue in other Formulations.

    markfuller@microformulation.com Microformulation.com Microformulation Cosmetic Consulting provides Custom Formulations for both large Commercial accounts as well as smaller entrepreneurs. We can provide Naturally compliant Formulations under the NSF, NPA, Whole Foods and USDA Organic Certifications. BS.Pharm Albany College of Pharmacy, Union University.
  • DoreenDoreen Member
    @Microformulation
    I thought allantoin precipitate was different, like tiny shards? I can be mistaken though. The betaine is there to keep this amount of allantoin solubilized. It also dissolves faster. First I dissolve betaine in the heated water phase and after that the allantoin, a bit of stirring and voilà: it's dissolved! (It also works with salicylic acid)
    I didn't know 1.5% is above allowable cosmetic levels? I assumed it was allowable up till 2%. Thanks for clearing that up! :+1:
    What are your thoughts about the last part I wrote about betaine and allantoine being amphoteric?

    @Gunther
    The graininess is soft, could it be lipophilic substances?
  • ozgirlozgirl Member, PCF student
    It is possible that you are experiencing "pilling" with your cream.
  • em88em88 Member
    Try to apply it on a surface like plastic or paper (black and white) and see if the same thing happens. 
  • ELF LOL
    Dr. Catherine Pratt
    (B.Sc with HONS I , Ph.D Analytical/Organic Chem and Microbiology), Cosmetic Chemistry IPCS)
  • DoreenDoreen Member
    @ozgirl
    Yes, I think that is it! Thanks! :blush:

    @em88
    Ok, thanks will try that!

    @Dr Catherine Pratt
    ?
  • Sorry its something we all go through, its called Epic Lotion Failure and I feel for you as I know how annoying it is losing your precious ingredients. Best of luck with your formula.
    Dr. Catherine Pratt
    (B.Sc with HONS I , Ph.D Analytical/Organic Chem and Microbiology), Cosmetic Chemistry IPCS)
  • DoreenDoreen Member
    edited May 2018
    @Dr Catherine Pratt
    I really had no idea what that abbreviation meant! :joy:
    Oh well, it wasn't that much of a failure really, as long as I apply a single, normal layer of cream, there's nothing wrong with it! :blush:

    Just had to share this: :joy:

      
  • DoreenDoreen Member
    @ozgirl
    I googled on 'pilling' and searched here on the forum, but apart from skincare routine advice, I can't find any help about it.
    Do you know some reasons that can cause it to happen? And how to prevent it?
    Thanks! 
  • gld010gld010 Member
    Can't Shea Butter get grainy sometimes?
    I can't find anything in your IL that'd cause pilling (in my novice-like opinion at least). In my experience, pilling can be caused by xanthan gum or other aqueous thickeners as well as lots of thick silicones (silicone likes to stick to itself which can cause pilling)...
  • edited May 2018
    That’s great!!
    Dr. Catherine Pratt
    (B.Sc with HONS I , Ph.D Analytical/Organic Chem and Microbiology), Cosmetic Chemistry IPCS)
  • Bill_TogeBill_Toge Member, Professional Chemist
    @Doreen my old gaffer frequently used to mutter "stupid machine!" whenever dealing with computers, though that was mainly because our IT systems were so unreliable we'd have been better off with typewriters
    UK based formulation chemist. Strongest subjects: hair styling, hair bleaches, hair dyes (oxidative and non-oxidative) I know some stuff about: EU regulations, emulsions (O/W and W/O), toothpaste, mouthwash, shampoos, other toiletries
  • DoreenDoreen Member
    @gld010
    That's true, maybe I can try and skip the shea the next time, thanks!
  • Doreen have you got your temps right?
    Dr. Catherine Pratt
    (B.Sc with HONS I , Ph.D Analytical/Organic Chem and Microbiology), Cosmetic Chemistry IPCS)
  • Good suggestion @Dr Catherine Pratt

    I get graininess with glyceryl stearate citrate if I rush the heating of the oil phase or if the water phase temp is too low when trying to form the emulsion. 

    Never noticed compatibility issues with betaine in a similar formula at pH 4.
  • This has happened to me when the temp was too low. 70 to 75%. You can make the oils hotter ( not over 80 though) but periodically blend the oil phase as they all have various MP's.
    Hope this helps cheers Catherine
    Dr. Catherine Pratt
    (B.Sc with HONS I , Ph.D Analytical/Organic Chem and Microbiology), Cosmetic Chemistry IPCS)
  • DoreenDoreen Member
    @Dr Catherine Pratt @EliseCortes
    Thanks for the suggestions! I didn't write the temps down and I can't remember, but next time I will pay more attention to that!
  • DoreenDoreen Member
    I've got an answer on my question (below the formula in the first post ^ , after 'edit')

    "Allantoin is an amphoteric molecule. It can have a positive charge under acidic conditions, but could only have a negative charge under very basic conditions. Betaine on the other hand can only have a positive charge under very acidic conditions, and it's usually present as a zwitterion (both anionic and cationic charges at the same time, with a net carge of zero). It could never be anionic since it has a permanent positive charge. At the pH of 5.32, allantoin is cationic, so it might actually interact with the anionic emulsifier. You basically suspend allantoin due to its low solubility and recrystallization risk. Incorporation into an emulsion during the cool down phase is done in the same way as you do with many other ingredients, only that you need vigorous mixing."

    I accidently put this underneath some of my other discussions, but it's about this emulsion. So the minor problems I had could indeed be due to the allantoin interacting with the GMS citrate.
Sign In or Register to comment.