Comments

• Agate Member

  March 6 edited March 6

  I'm confused, what type of product are you trying to make?
  

  If you're just looking to solve your own seborrheic dermatitis, I would look into a shampoo containing the antifungal agent ciclopirox olamine. I can't find the source anymore, but read that unlike with ketoconazole, malassezia doesn't adapt to it, so it stays effective in the long term. As a life-long sufferer of seborrheic dermatitis, this is the only thing I've found to keep it under control permanently for me.
  

  
  
• Pharma Member, Pharmacist

  March 6

  Don't you need an emulsifier?
  
• Sylarana Member

  March 7

  I have seborrheic dermatitis and I've also tried experimenting with urea. I've tried urea in water, urea with buffer in water, urea in emulsion (without buffer as I use only polymeric emulsifiers, and they generally don't tolerate electrolytes). I made several test batches and then measured pH. Without buffer the pH rose, it was closer to 8 within a week. With the buffer it fared much better. Have you read this topic? It has advice on how to make a buffer. 
  As an aside, have you tried Hada Labo or Uremol 10 cream? You might be able to tolerate them.
  You can try making an emulsion with your Sepimax Zen. I've never used it so I don't know if it is able to tolerate that much oil (you list 15-20% CCT) and a buffer. Maybe, try less oil and 2% gluconolactone, as it was recommended in the urea cream formulation I've seen somewhere. Personally I've just abandoned urea as an ingredient as I haven't seen any difference. 
  
• Agate Member

  March 7

  (Found the source again, just adding it here for good measure in case someone is interested: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6615394/)
  
  
• wannabe_chemist Member

  March 7

  Thanks for the responses Sorry, I should have said I'm attempting to make a gel-cream. Lotioncrafter says Polyacrylate Crosspolymer-6 (Sepimax zen on LC) emulsifies up to 25% oils with xanthan gum. I'll definitely start on the lower side with the oil.
  
  My face really hates any cleansers/antifungal shampoos so I try to avoid them. I've had luck with Hamilton urea cream (same ingredients as uremol 10 cream) but it has petrolatum in it. So, I need a cleanser to properly take it off. It makes my skin baby smooth and gets rid of any signs of SD but using a cleanser irritates my face so much. It's so weird how everyone is different in what works for them! 
  
  Gluconolacctone was something I was considering too, thanks From what I understand is that it has a pH drift toward alkaline and urea has a pH drift toward becoming acidic. Do you know what phase the gluconolacctone is added to? Can I just add it at the end?
• ngarayeva001 Member

  March 8 edited March 8

  It is a very bad idea to start with such a product. You need a proper buffer to lock down the pH. Or I read you can formulate it in w/o format not to worry about pH shift for urea. But you can't start with w/o without experience with o/w.
  Sepimax zen is a fantastic material in general but even this one might not be able to deal with urea. 
• wannabe_chemist Member

  March 8 edited March 8

  ngarayeva001 said:

  It is a very bad idea to start with such a product. You need a proper buffer to lock down the pH. Or I read you can formulate it in w/o format not to worry about pH shift for urea. But you can't start with w/o without experience with o/w.
  Sepimax zen is a fantastic material in general but even this one might not be able to deal with urea. 

  Thank for your advice, I appreciate it! How do I know if an emulsifier is o/w or w/o? Do you know if urea's pH drifts significantly within a few weeks? 
  
  If urea doesn't do well in o/w emulsions, does it not do well in aqueous products like toners/serums? Would the main issue be the pH drift? If I made a simple urea toner and checked the pH to make sure it doesn't drift, would that indicate it is stable?
  
  I found this pretty simple 4% urea serum on humblebeeandme:
  

  https://www.humblebeeandme.com/soothing-hyaluronic-acid-facial-serum/

  which is pretty much water, aloe, sodium lactate, Propanediol 1,3, preservative. Not sure if this would be stable or not.
  
  
  I forgot to mention the buffer in my post because I wasn't sure what the final pH would be and if it was necessary. I was thinking sodium lactate, lactic acid or gluconolactone.
  
  
  
• wannabe_chemist Member

  March 8 edited March 8

  I just noticed that makingcosmetics says w/o or o/w emulsifiers. The only one under w/o emulsifiers that would work for me is Creammaker silicone (Cetyl diglyceryl tris(trimethylsiloxy)silylethyl dimethicone). "Liquid Silicone Water-in-Oil Emulsifier"

  
  It says here: https://www.makingcosmetics.com/fact-sheets/fact-sheet-creammaker-silicone.pdf  , that Creamaker silicone has an 'HLB value' of 2.
  
  but on this page: https://www.makingcosmetics.com/FAQ-HLB-Value_ep_122-1.html
  
  it says 
  HLB 1 - 3: Antifoaming Properties
  HLB 3 - 8: w/o-Emulsification
  HLB 7 - 9: Wetting Properties
  HLB 9 - 18: o/w-Emulsification
  HLB 15 - 20: Solubilizing Properties
  
  So I'm confused if it has an HLB of 2, how can it be a w/o emulsifier?
  ----
  
  Does anyone know if Emulthix from lotioncrafter is w/o or o/w? Or if anyone has a reading material they can suggest to me, please do! 
  
  
• jemolian Member

  March 9

  From my experience with making a Urea creams, here's what i'd recommend with the similar ingredients. 
  
  Water Phase
  

  • Distilled Water
  • Glycerin (1.5% - 3%)
  • Urea (5%)
  • Buffer - Triacetin (0.25%) 

  Oil Phase
  

  • Caprylic/Capric Triglycerides (15% - 20%)
  • Sepinov EMT 10 (1.2%)

  Others
  

  • pH Buffer - Lactic Acid (q.s)
  • Preservative as required

  Instructions:
  

  1. Dissolve/add the ingredients into the distilled water 
  2. Slurry the Sepinov EMT 10 in the CCT
  3. Add the slurry into the water phase and mix till gel
  4. Add the remaining ingredients 

  --- 
  
  I'd recommend to make a fresh batch to retain the maximum effect of the Urea since it will break down in water over time. You can make one batch ever 2 months or so? You can observe the pH and for any bubbling.
  
  The pH shouldn't shoot up as much with the Triacetin, however you can choose to use other buffers, then you can opt for Sepimax Zen, if not the Sepinov EMT 10 should be easier to deal with as the Sepimax Zen requires some hydration duration. 
  
  http://www.iscd.it/files/UREA-FROM-THE-CHEMIST-S-POINT-OF-VIEW.pdf
  
• wannabe_chemist Member

  March 9 edited March 9

  jemolian said:

  From my experience with making a Urea creams, here's what i'd recommend with the similar ingredients. 
  
  Water Phase
  

  • Distilled Water
  • Glycerin (1.5% - 3%)
  • Urea (5%)
  • Buffer - Triacetin (0.25%) 

  Oil Phase
  

  • Caprylic/Capric Triglycerides (15% - 20%)
  • Sepinov EMT 10 (1.2%)

  Others
  

  • pH Buffer - Lactic Acid (q.s)
  • Preservative as required

  Instructions:
  

  1. Dissolve/add the ingredients into the distilled water 
  2. Slurry the Sepinov EMT 10 in the CCT
  3. Add the slurry into the water phase and mix till gel
  4. Add the remaining ingredients 

  --- 
  
  I'd recommend to make a fresh batch to retain the maximum effect of the Urea since it will break down in water over time. You can make one batch ever 2 months or so? You can observe the pH and for any bubbling.
  
  The pH shouldn't shoot up as much with the Triacetin, however you can choose to use other buffers, then you can opt for Sepimax Zen, if not the Sepinov EMT 10 should be easier to deal with as the Sepimax Zen requires some hydration duration. 
  
  http://www.iscd.it/files/UREA-FROM-THE-CHEMIST-S-POINT-OF-VIEW.pdf
  

  Thank you SO much! I really appreciate it. I've been very stressed about trying to figure this out by myself. I'm so glad you posted that article because I thought urea had a pH drift in the opposite direction. 
  
  I wouldn't mind making it every couple weeks if I had to!
  
  I'm not sure if Triacetin (Glyceryl Triacetate) is 'safe' for seborrheic derm but at .25% I doubt it would be a problem. I think I will give Triacetin a try!
  Maybe I can try a batch with sodium lactate or Gluconolactone instead of Triacetin and compare them too.
  
  Thank you again for taking the time to help me I'm going to take your advice! So incredibly helpful! I'm feeling a lot better about this now.
  
  edit: Do you know if Sepinov EMT 10 is classified as a w/o or o/w emulsifier? I still have no idea how to tell. >.<
• jemolian Member

  March 9

  Well, if you want to use Sodium Lactate or Gluconolactone, that would be fine as well.
  
  Though with the Sodium Lactate, you will need to use Sepimax Zen or no polymeric emulsifier at all as they won't be able to take the electrolytes. You can consider your previous combination, Sepimax Zen + Gum, if not a normal emulsifier with fatty alcohol or acid should be fine as well.  
  
  With Gluconolactone, the pH will go in 2 directions so the ultimate amount to add would vary. Not sure if it's something that you want to try out but it's this formulation would be one that you'd need to observe more closely. 
• wannabe_chemist Member

  March 9

  jemolian said:

  Well, if you want to use Sodium Lactate or Gluconolactone, that would be fine as well.
  
  Though with the Sodium Lactate, you will need to use Sepimax Zen or no polymeric emulsifier at all as they won't be able to take the electrolytes. You can consider your previous combination, Sepimax Zen + Gum, if not a normal emulsifier with fatty alcohol or acid should be fine as well.  
  
  With Gluconolactone, the pH will go in 2 directions so the ultimate amount to add would vary. Not sure if it's something that you want to try out but it's this formulation would be one that you'd need to observe more closely. 

  I'm gonna stick with your first generous recommendation, lotioncrafter makes it all sound so simple.  I thought I once heard gluconolactone had a pH drift downward, thank you for clearing that up.
  
  I wouldn't have thought of sodium lactate as an electrolyte but now that you say it, it's pretty obvious it is. I wish urea wasn't so tricky, i'd love to just stick it in some water with a buffer and call it a day. But I've heard it doesn't do well in aqueous solutions.
  
  Would it be ridiculous to mix some urea in distilled water every day and not worry about any of this? lol
• jemolian Member

  March 9

  There shouldn't be any issues if you mix and use it daily but making a 15ml solution daily can be rather tedious, though you can pre-measure the amount into small containers. 
• wannabe_chemist Member

  March 9

  I would rather not mix it up every day (not sure if mixing the small amount urea every day is hazardous or not lol). Right now I'm mixing up honey masks and wearing them for 3 hours every few days in lieu of urea. Which is also tedious but I don't mind too much.
  
  Could you please tell me where you buy your Triacetin?
• jemolian Member

  March 9

  I usually buy most of my ingredients from China but you can see if you can purchase from here https://shop.perfumersapprentice.com/p-7197-triacetin.aspx
• wannabe_chemist Member

  March 9

  you're so cool! Do you use alibaba.com or something usually?
• jemolian Member

  March 9

  No, usually i purchase my ingredients from repackers / resellers on taobao and forward the shipment to my country in Singapore. The sellers in China holds slightly different ingredients compared to the ones in the US or UK/EU. 
• ngarayeva001 Member

  March 9

  @wannabe_chemist, humblebeeandme is not a source I would advise anyone to follow.
   
  Re: water in oil, trust me you need to master o/w first. W/O take a lot of knowledge and months (if not years) of practice. 
  
  Let's start from the beginning. Do you want to make a moisturiser for very dry skin? If this is what you are trying to achieve, there are plenty of good humectants and good occlusive materials that work pretty well. Don't start with a problematic material that requires years of experience. You still can make a decent product that will do what you want and will be elegant upon application. 
  You need glycerin, sodium lactate (or sodium PCA or both), chelating agent (disodium EDTA) petrolatum, mineral oil, a good broad-spectrum preservative (germaben II is good), anhydrous lanolin, a decent emulsifier (GMS+PEG-100 stearate, Ceteareth 20),  thickener (cetearyl alcohol, cetyl alcohol) and some sort of stabiliser (Zen would work, but you can go for xanthan). 
  
  
• wannabe_chemist Member

  March 9 edited March 9

  ngarayeva001 said:

  @wannabe_chemist, humblebeeandme is not a source I would advise anyone to follow.
   
  Re: water in oil, trust me you need to master o/w first. W/O take a lot of knowledge and months (if not years) of practice. 
  
  Let's start from the beginning. Do you want to make a moisturiser for very dry skin? If this is what you are trying to achieve, there are plenty of good humectants and good occlusive materials that work pretty well. Don't start with a problematic material that requires years of experience. You still can make a decent product that will do what you want and will be elegant upon application. 
  You need glycerin, sodium lactate (or sodium PCA or both), chelating agent (disodium EDTA) petrolatum, mineral oil, a good broad-spectrum preservative (germaben II is good), anhydrous lanolin, a decent emulsifier (GMS+PEG-100 stearate, Ceteareth 20),  thickener (cetearyl alcohol, cetyl alcohol) and some sort of stabiliser (Zen would work, but you can go for xanthan). 
  
  

  I agree humblebeeandme is probably not the best source in the world. The only reason I have to go through all the trouble of making my own product is for a urea a product though. I have seborrheic dermatitis which feeds on anything with a carbon chain length of 11-24 (which rules out mostly all emulsifiers).
  
  I've solved all my skin concerns expect for one. The layer of crust that develops from Sebderm after a couple days of not doing honey masks or having a 10% urea cream on my face. Problem is, it has petrolatum in it and my skin just can't handle being cleansed all the time.
  
  The ingredients for the 10% urea cream are:
  

  Water, mineral oil, urea, glycerin, petrolatum, cetearyl alcohol, cetyl alcohol, triethanolamine, carbomer, ceteareth-20, methylparaben, ethylparaben, butylparaben, propylparaben, isobutylparaben.

  Here is another 10% urea cream almost identical:

  Water, Mineral Oil, Urea, Glycerin, Petrolatum, Ceteth-20, Cetyl Alcohol,  Cetearyl Alcohol, Triethanolamine, Carbomer, Phenoxyethanol, Methylparaben, Propylparaben, Lactic Acid

  
  

  Maybe I can try to recreate something like this. Just drop the petrolatum and do 5% urea instead.  I'm perfectly okay with trying and failing. At least I can cross it off my list of things to try. I know urea is an ingredient that works for me. 

  How does one know if they are using a w/o or o/w emulsifier if the manufacturer doesn't tell you? And is urea the problematic ingredient in this case?

   Can I just drop the lotion idea entirely and throw urea in some water with a buffer and preservative? 

  Kinda mad that the safety data sheet for urea on makingcosmetics and lotioncrafter makes it sound like you can do almost anything with it and not mess up. They don't mention the pH drift of urea either. 
• ngarayeva001 Member

  March 9

  Unfortunately, DIY websites don't share much info on how to formulate with an ingredient.
  Speaking of how do you know whether it's w/o or o/w, you can google it. Ulprospector (even the free version) is usually good at saying what kind of emulsifier it is. 
• Lisa2190 Member

  March 13

  @wannabe_chemist A sincere question, here... why do you not recommend Humblebeeandme? I am a fledgling chemist and have used a few recipes from there with no problem, but wondering what you might know that I don't? Thanks for your response
  
• wannabe_chemist Member

  March 14 edited March 18

  @Lisa2190 I was only agreeing with @ngarayeva001 that humblebeeandme might not be the most credible source in the world because I really don't know much about them. I mean, her entire website is dedicated to DIY, so her knowledge is far better than the average person's. If ngara knows something more than that, maybe he can tell you.
  
• wannabe_chemist Member

  March 18

  @Lisa2190 I'm gonna say humblebeeandme is fine at this point. Ngara doesn't like to answer questions only scaremonger. 
• alchemist01 Member

  March 18

  As far as DIY sites go, humblebeeandme is one of the better ones. I have used her website as a starting point for some stuff before, really because she's the only one that posts formulas with actual %s and gram measurements, rather than cups.
  It's still a DIY website, though, and is probably best for advanced hobbyists. 
  
  The other poster is just trying to tell you urea creams are difficult to formulate and I think they are right. You are welcome to try but I would encourage you to be less dismissive of help.
  My lab made a 10% urea cream with Cithrol DPHS (PEG-30 Dipolyhydroxystearate). I wasn't involved with it but have made w/o emulsions with that emulsifier and think it could work for you.
• wannabe_chemist Member

  March 18 edited March 18

  @alchemist01 it's not help when he just scaremongers and refuses to answer questions. It wasn't helpful to me in any way. He asked me if I just wanted to make a moisturizer for dry skin and stated there are plenty of good humectants that I can use instead.
  
  The very first thing I said in my very first post was "After struggling to find a urea product that is 'safe' for seborrheic dermatitis, I've decided to try and make my own. I want to start simple and then add to it. "
  
  @jemolian was incredibly helpful and I'm truly grateful for his response. But he provided something helpful to assist my project. Not completely bashing the very thought of it.
  
  Ngara says " Don't start with a problematic material that requires years of experience."
  
  I asked him " And is urea the problematic ingredient in this case?" No response. He just keeps telling me " trust me you need to master o/w first. W/O take a lot of knowledge and months (if not years) of practice. "
  
  So I tried to ask if I could just ditch the lotion idea all together and put some urea in a toner with a buffer and a preservative. He won't answer if his problem is with me trying to make a w/o emulsion or if the problem is urea.
  
  Why does lotioncrafter and makingcosmetics make it seem like you can just mix it into anything and there will be no problems. 
  "Reactivity: Not reactive under normal conditions of use"
  "Chemical Stability: No known hazardous reactions"
  "Possibility of Hazardous Reactions: Will not occur"
  "Conditions to Avoid: Gross bacterial contamination"
  "Hazardous Decomposition Products: Urea is decomposed by heating and can form products including ammonia..."
  
  I'm not gonna heat it, I'm not using sewer water, so what exactly is the problem is my question.
  
  I'm not keeping this product around for months at a time. I've come to find (through the help of jemolian and other sources) that as long as the pH isn't drifting, there are no bubbles forming, or crystals forming, then the urea is most likely fine. I tried asking this question too, what exactly is it about urea that is so difficult to formulate with? no answer just simply don't do it, you're gonna die
• alchemist01 Member

  March 18

  Urea is not particularly stable. Evaporation of water can crystal formation. Temperature fluctuations (I believe within ambient range) and air exposure can cause pH drift.
  According to this paper (http://www.iscd.it/files/UREA-FROM-THE-CHEMIST-S-POINT-OF-VIEW.pdf), urea creams above 10% should be W/O emulsions. "For the treatment of pronounced dermatological disturbances such as psoriasis vulgaris, different forms of ichthyosis, atopic dermatitis and extremely dry skin, 10% U in W/0 should be applied (5,6). U in W/0 has not such a distinct immediate effect but has a longer lasting beneficial action due to its deeper penetration into the skin." W/O emulsions are inherently trickier. For these reasons, and a lot of anecdotal evidence from my coworkers, I view it as a problem in formulating. However, again, I have not worked with it.
  
  If you feel you have been helped I'm glad. I really don't see a problem with you making a batch of this stuff and closely watching its stability. Do know a lot of people that try to help on this website are professionals and don't have time to respond to every reply, I don't think you should get upset with anyone over that.
• EVchem Member

  March 18

  https://online.personalcarecouncil.org/ctfa-static/online/lists/cir-pdfs/pr310.pdf < Here is the safety report for urea. This article is long but you don't need to read all of it. 
  
  The only major safety concern I can think of is the fact urea is a good penetration enhancer, so be careful what else you mix it with.  I don't see a problem with a 'urea toner' , and it's easier to start simple and work your way up- maybe you just add a gum to thicken the toner for easier application before you tackle an emulsion with it.
  
  
• Pharma Member, Pharmacist

  March 18

  The problem with urea is it's degradation which theoretically shouldn't occur but regularly does in every industry. Why exactly, we don't know but it tends to hydrolyse (the exact mechanism is only partially known and partially speculative and/or formulation dependent). Problem No. 1: Full hydrolysis results in 1 part CO2 and 2 parts ammonia -> depending on pH, you'll get a lot or twice a lot of gas bubbles. Problem No. 2: Partial degradation results in formation of cyanide and derivatives thereof.

  Gotta run, watch the news (corona as usual, I'm quite sure about that).
  
• jemolian Member

  March 19

  @wannabe_chemist well, i hope you are not discouraged with formulating with Urea. Perhaps i only find that the issue would only be if you are selling it thus needing to maintain the pH. If not, there shouldn't be any issues by making small batches if it with a suitable buffer for home use where you can monitor the changes with pH. I've made quite some Urea creams myself, usually 50ml batches. 
  
  Regarding Humblebeeandme, i find that for Marie's content, it has evolved from kitchen DIY to something more experienced, so i'd only recommend for reference for people that are either beginners or intermediate levels.  
  
  
• wannabe_chemist Member

  March 19

  @alchemist01 thank you for your response, it does indeed help! In regard to your statement " Do know a lot of people that try to help on this website are professionals and don't have time to respond to every reply, I don't think you should get upset with anyone over that."
  
  I completely agree, and I don't expect anyone to go out of their way to help me. That is why I was respectful and grateful for any response. Even when he was crapping on my entire concept, I was still respectful. He then crapped all over humblebeandme and couldn't answer a simple question to state WHY. After 5 days of waiting for a response, I decided to tell the person who asked me about why humblebeandme was not a good source that he just wants to spread fear for some reason. It would be one thing if he just didn't have time to respond but he has been active on this forum every day.
  
  I was very excited to finally try and make a urea product after spending over a year trying to find the perfect one. I had been contemplating it for months and months and I finally went through with it after spending much time researching it. If I could just buy the perfect product with 5% urea, I'd rather do that, but I don't have that option.
  
  After reading his comments, all my ingredients are just sitting in a box in a closet. I don't know why anyone would discourage someone without giving them a reason why. I'm gonna give it a shot, maybe I'll start with a simple 'toner' and monitor how it changes. Now I know what to look out for! (information that falls under the helpful category... not discouragement). But anyway, enough of that. 
  
  Thank you @EVchem, @Pharma, and @jemolian for your tips you have no idea how much it helps a "wannabe chemist" out! And jemolian, I have no intentions of selling this or keeping it around for months at a time for that matter. I just want to try and maintain my seborrheic dermatitis with it. You've been so great, I really appreciate you taking the time to help me. 
• Pharma Member, Pharmacist

  March 19

  I had a customer at the pharmacy where I used to work who loved THIS eye cream but wasn't too happy with it containing not enough urea. Given all the benefits of urea combined with her high appreciation of that particular cream and my careful/minimalist attitude, the solution was obvious: When she bought a pot, which was about once a month, I simply put 5 g of pure urea on top of the new 50 g cream pot, mixed it with a tiny spatula, let sit for a minute, remixed and tada!

  Every time a perfect cream and a happy & satisfied customer.

  Urea, if it doesn't lead to emulsion destabilisation, is so super water soluble, that it can easily be mixed into a cream/lotion afterwards, like making 200 g stable urea-free cream and then taking smaller aliquots wherein you mix urea right before starting to use respective tiny pot. Should urea turn out to be super unstable in a product, mixing can even be done in your hands by roughly estimating 10% by eye just before you apply the cream (probably weigh cream and urea the first 1-2 times to get a better visual judgement). If your off by a few % it's highly likely that it won't matter. Urea is quite forgiving in that regard.
  
• ngarayeva001 Member

  March 19 edited March 19

  It looks like I missed the party?  Humblebeeandme measures essential oils in quote ‘blobs’ and suggests using a surfactant not intended for liquid product for use in shampoo. If someone is in a doubt she is not an appropriate source go to her blog and see how she makes a foundation and what insanity she suggests to use as a color blend. She’s a dilettante, full stop. I do not recommend anyone using that source to lean formulating unless you want to stay on her level make ‘concoctions’ and share ‘recipes’. @wannabe_chemist, next time you want to get an answer do tagging properly. 
• lewhitak Member

  March 20

  Well, I think Humblebeeandme is very much a DIY blog and should really be treated as that. The author is very clear on that as well. She does an awesome job at creating DIY recipes for home users but I wouldn't expect in-depth chemical stability analysis from a DIY blog. That is a bit of an unfair expectation to put on DIY since it is supposed to be useful for any home user versus chemists or industry professionals. 
  
  
• wannabe_chemist Member

  March 24

  @Pharma that is brilliant! thank you
• ngarayeva001 Member

  March 24 edited March 24

  @Pharma, the cream you mentioned is water in oil. This approach might be slightly problematic with o/w, which are the majority of moisturisers on the market. 
• Pharma Member, Pharmacist

  March 25

  @ngarayeva001 Not at all! Urea is soluble in the water phase and because it's so hydrophilic, it even works with water as the internal phase (that's why it required a minute waiting between the two mixing steps). Imagine how fast you'll be with water as outer phase .
  
• ngarayeva001 Member

  March 25

  I agree it will incorporate easily, but it might cause ph shift and hydrolysis. Unless you make tiny batches and use them up very quickly. It’s up to the formulator, I prefer not to take a risk with o/w. Another point, I don’t know if it’s me or anyone else noticed it, sodium lactate feels more moisturizing than urea. I compare 3% pf sodium lactate vs 5% of urea.