Home Cosmetic Science Talk Formulating Unstable creams?

  • Unstable creams?

    Posted by Anonymous on August 22, 2014 at 7:54 am

    Hi there.

    I created a range of different creams for a buyer. I filled the bottles all the way up, but when they arrived the bottles where half empty? I find this extemely strange.

    I have also noticed that over time small bubbles begins to form on the sides of the glass.

    I also noticed that the cream with hyaluronic acid, Hydrating Moisture Cream, lost it viscosity and becomes like a milk.

    Here is the formulas:

    Anonymous replied 9 years, 10 months ago 3 Members · 8 Replies
  • 8 Replies
  • Chemist77

    Member
    August 22, 2014 at 9:35 am

    In the first place I am a bit surprised to see the oil phase quantity and imagining how much they could have been helpful to build the viscosity. Secondly the bulks were most probably highly aerated at the time of filling and now when you received the bottles they are half empty once the air bubbles vanished. The ones you see now are some of those which could persist till the delivery. No one did the glass slide test to check the air entrapment??????

  • Anonymous

    Guest
    August 22, 2014 at 10:50 am

    So what you are saying @milliachemist is that the oil quantity should be higher? Right now we only use a noraml hand heal mixer. Do you think it will be easier to formulate and work with a homogenizer? We have it on our list.

  • Chemist77

    Member
    August 22, 2014 at 12:43 pm

    The kind of formula that you are using most definitely calls for any such mixer which minimizes or eliminates the possibility of air entrapment.

  • Anonymous

    Guest
    August 22, 2014 at 1:36 pm

    Alright. We will most definitely buy a high sheer mixer then. Thanks!

  • cossci21

    Member
    August 25, 2014 at 9:27 pm

    As a general rule seeing as you have quite a bit of emulsifier usually about 10% oil will produce a more stable cream. Playing with the ratio can often produce a better emulsion.

  • ssdc

    Member
    August 28, 2014 at 3:26 am

    Can you briefly explain about the glass slide test

    Thanks
  • Chemist77

    Member
    August 28, 2014 at 3:57 am

    @ssdc Take a drop of finished emulsion between 2 glass slides, rub the slides a little and see under a source of light. Would give you a rough idea of aeration in your emulsion. 

  • Anonymous

    Guest
    September 5, 2014 at 9:08 am

    Hi there everyone.

    I’ve been formulating a bit.

    14,5% squalaine
    1,5% jojoba esters = HLB 12,5



    16%/4 = 4% emulsifier needed

    Emulsifiers:
    Cetearyl Glucoside (HLB 11)                      27.5%   1.1%
    Sodium Stearoyl Lactylate (HLB 6,5)         15%      0.6%
    Glyceryl Stearate Citrate (HLB 11)             12.5%   0.5%
    Cetearyl Alcohol (HLB 15,5)                       45%      1.8%
                                                                       100%     4%

    The rest was used with water to test.

    The emulsion is a little thin and milky. Can I higher the emulsifiers to get a thicker cream, or will this break the rule of 1/4 of the oil pharse as emulsifier %?  And will it cause more soaping? Will the jojoba make the formula thicken over time?

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