Home Cosmetic Science Talk Formulating Skin pH of cationic emulsion for skin. Above or below it’s isoelectric point which is 4.8

  • pH of cationic emulsion for skin. Above or below it’s isoelectric point which is 4.8

    Posted by Abdullah on July 22, 2022 at 3:41 am

    The isoelectric point of skin is 4.8. 

    A simple cation lotion for skin that has BTMS or BTMC + fatty alcohol as emulsifier+ petrolatum+ glycerin, is it better for skin to adjust the product pH to below 4.8 or above it and why? 

    Fekher replied 2 years, 5 months ago 3 Members · 14 Replies
  • 14 Replies
  • Fekher

    Member
    July 22, 2022 at 4:10 am
  • Abdullah

    Member
    July 22, 2022 at 3:44 pm

    Fekher said:

    Thanks

  • ketchito

    Member
    July 22, 2022 at 3:51 pm

    @Abdullah Due to the irritation from cationics in leave-on products for skin, cationic emulsions are usually not the first choice as emulsifiers, but (ethoxylated) non ionic ones are. 

    In hair, the story is different. From a rinse off product, the cationics remaining will be the ones that managed to interact with functional sites in hair; in leave on, it’ll be the ones that are part of the film covering each fiber. But on skin, way more product can remain in contact with skin for longer periods of time. Plus, for skin you don’t need the type of conditioning a cationic surfactant gives to hair. There are more choices avaliable to lubricate the skin.

  • Abdullah

    Member
    July 23, 2022 at 7:20 am

    @ketchito thanks 
    I use only 0.5% cationic surfactant+ fatty alcohol in emulsion. 
    People who has used these cationic emulsions all liked it more than emulsions with these anionic & non-ionic surfactants (GMS, sodium stearoyl lactylate, polyglyceryl-4 laurate) stabilized with xanthan gum. Do you think 0.5% BTMS or BTMC will cause irritation?

    For me cationic emulsion has a lot of advantages and most importantly somehow the final product costs less than emulsion with very inexpensive anionic & non-ionic emulsifiers mentioned above. 

  • Fekher

    Member
    July 23, 2022 at 8:05 am

    You are welcome @Abdullah just I want to know for that type of cream your emulsifier combination is only cationic surfactant + fatty alcohol?

  • Abdullah

    Member
    July 23, 2022 at 8:10 am

    Fekher said:

    You are welcome @Abdullah just I want to know for that type of cream your emulsifier combination is only cationic surfactant + fatty alcohol?

    Cationic surfactant+fa+ petrolatum+ glycerin+ preservative+ fragrance+ water. 
    pH adjusted with lactic or citric acid.

    No unnecessary or marketing ingredients ????

  • Fekher

    Member
    July 23, 2022 at 9:16 am

    @Abdullah very interesting what you are doing just in theoric 0.5% cationic +fa seems as a weak emulsifier combination  but I guess the secret is using petrolatum in oil phase that gives more stability for emulsion product. Keep making original things brother ????

  • Abdullah

    Member
    July 23, 2022 at 9:43 am

    I forgot. I used NACL too in cationic emulsion. It pased three months  puting bottle in window, hot in day and colder at night stability test and pased 3 cycle freeze Thaw cycle. I think this product is very much stable. maybe the combination makes it stable. 

  • Fekher

    Member
    July 23, 2022 at 9:59 am

    @Abdullah soo strange adding salt for such system is it for viscosity or preservation boost or what?! I guess cationic have preservative property then is not strange to have good stability. 

  • Abdullah

    Member
    July 23, 2022 at 10:04 am

    It was for viscosity and stability. 

  • Fekher

    Member
    July 23, 2022 at 10:08 am

    Thanks @Abdullah my guess was fine then ????. 

  • Fekher

    Member
    July 24, 2022 at 8:57 pm

    @Abdullah I read that ionic emulsifier are electrolyte sensitive , then have you an explanation how in your case Na CL make your cationic emulsifier more stable? 

  • Abdullah

    Member
    July 25, 2022 at 12:13 am

    I don’t have explanation for it. A chemist here told me to do so, i did and got the results. I don’t remember it correctly but i think it didn’t work in anionic emulsion.

  • Fekher

    Member
    July 25, 2022 at 12:18 am

    Fine @Abdullah whatever nice share from you and wish any one can give us explanation about that. 

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