Deodorant stick - my formula has condensation | Help

marinaartmmarinaartm Member
edited September 23 in Formulating
Hi there!
So i made this recipe for deodorant stick:
Phase A:
Almond oil: 28%
Squalane: 5%
Grapeseed oil 9%
Cetearyl alcohol 10%
Beeswax: 15%
Olivem 1000: 6,8%

Phase B
Tapioca starch: 13%
Zinc ricinoleate: 3%
Glycerin: 8%
Activated charcoal: 0,1%

Phase C
Vit E: 0,1%
Essential oil: 2%

I heated phase A to @80 C, took it out and then added 1by 1 the ingredients from phase B and put the composition back to heat it a bit more.
I left it to cool, maybe to @70 C and added Phase C. I took the Ph and adjusted it to 5.5 with lactic acid

The deodorant seems ok, the only problem is that i noticed it has drops on it, some kind of condensation. 
Why do you think that happened? Something wrong in the formula?

Thank you so much for your help!

Comments

  • MicroformulationMicroformulation Member, Professional Chemist
    What is keeping the 8% Glycerin (water soluble) from separating from your anhydrous product?

    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.
  • What is keeping the 8% Glycerin (water soluble) from separating from your anhydrous product?

    I thought the emulsifier Olivem 1000+the co-emulsifier Cetearul alcohol are the ones that help integrate glycerin in the formula
  • Should i add the glycerin in water? maybe 10% water? Not sure how that will change the whole composition, plus i will need to add a preservative. 
  • The formula has more issues than "condensation".

    1. Can you tell me how did you measure the pH?

    2. You are using lipids that go rancid very easily, do you think 0.1% of an antioxidant will make sure the product will be fine for more then couple of months? 

    3. Not sure why are you using emulsifier, if you are not creating any type of emulsion? 

    Finally, what you are experiencing is (most likely) syneresis - Please check polarity of all lipids. I believe Squalane is non (or low) polar lipid, that could cause the issue. Try to remove it, update the formula and try again. 
    (you are not supposed to mix polar and non-polar lipids together)

    Hope that helps.
  • Paprik said:
    The formula has more issues than "condensation".

    1. Can you tell me how did you measure the pH?

    2. You are using lipids that go rancid very easily, do you think 0.1% of an antioxidant will make sure the product will be fine for more then couple of months? 

    3. Not sure why are you using emulsifier, if you are not creating any type of emulsion? 

    Finally, what you are experiencing is (most likely) syneresis - Please check polarity of all lipids. I believe Squalane is non (or low) polar lipid, that could cause the issue. Try to remove it, update the formula and try again. 
    (you are not supposed to mix polar and non-polar lipids together)

    Hope that helps.
    Hi @Paprik !

    1. I measure it with special paper at about 68 C. I know, not very exact due to the type of measuring and to the temperature but even if i will measure with a Ph meter, the temperature still it's too high. Any suggestions on this? 
    2. I think you are right so i will increase it to 0,5%
    3. I saw this recipe and the fact that Olivem 1000 provides a good glide, plus the recipe i did does feel nice: 
    I made another try today with MCT oil and almond oil only and until now it seems it has no problem.
    I will check the polarity of oils.
    Thank you so  much for your help!
  • marinaartmmarinaartm Member
    edited September 24
    Also, i am thinking of adding to the formula glycolic acid in a max of 5% because i researched it would be a good addition for the underarm area so i would like to try. But for that i need to add at least 10% water in order to dissolve it. I have never worked with glycolic acid so if anyone has any suggestions, please let me know

    Thank you!
  • @marinaartm I believe @Paprik questions were very fair.

    On one hand, pH measurement needs a polar media (like water, which you don't have in your initial formula). You can have a reading of course, but that would be from a single ingredient (like Glycerine). 

    Also, Vitamin E alone might not be powerful enough to protect your system, so you might need to consider another AOx.

    An emulsifier in a waterless formula is not necessary. But because of the lack of a water phase, Glycerine might not be properly incorporated in your mixture (8% is actually very high), and that might also explain the drops you see. 
  • ketchito said:
    @marinaartm I believe @Paprik questions were very fair.

    On one hand, pH measurement needs a polar media (like water, which you don't have in your initial formula). You can have a reading of course, but that would be from a single ingredient (like Glycerine). 

    Also, Vitamin E alone might not be powerful enough to protect your system, so you might need to consider another AOx.

    An emulsifier in a waterless formula is not necessary. But because of the lack of a water phase, Glycerine might not be properly incorporated in your mixture (8% is actually very high), and that might also explain the drops you see. 
    The second formulation i just made, with mct oil and almond oil does not have the droplets anymore. It seems fine, the only problem is that it does not keep the odor gone for long.
    So i am thinking that i should put an ingredient that has antibacterial properties, maybe glycolic acid or/and an antibacterial oil. And also add water so i can disolve the acid and properly take the PH
    What do you think @ketchito ?
  • GraillotionGraillotion Member
    edited September 25
    You could sure take a look at adding triethyl citrate.

    If I were making one....it would be in there.  (I don't make one....but I've thought about it more than once.)

  • You could sure take a look at adding triethyl citrate.

    If I were making one....it would be in there.  (I don't make one....but I've thought about it more than once.)

    Funny, right before seeing your comment i ordered triethyl citrate to use in the formulation. 
    Another option is magnesium hydroxide.
    Triethyl citrate works on the acidic Ph and magnesium hydroxide on the basic PH so they work differently. 

    Thank you for the suggestion @Graillotion
  • @marinaartm When I used in the past Triethyl citrate for a stick formula, I didn't have much luck, basically, since I needed quite some of that ingredient to get any benefit, but maybe you'll have more luck. I'd still consider the antibacterial route. I'd give Chlorhexidine undecylenate a shot. 
Sign In or Register to comment.