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  • Looking for constructive feedback on eye cream formula

    Posted by goska007 on February 19, 2022 at 2:54 pm

    Dear All,

    I’m new here! I am looking for constructive feedback and advice from those who are experienced with Montanov’s range.

    I am working on an eye cream formula, medium viscosity for a glass jar as a final container. 

    Formula:

    PHASE A

    Organic Floral Water   up to 100
    Solagum AX                0.2

    PHASE B

    Montanov 68                         1
    Montanov 202                       3
    Cetyl Palmitate                      3
    Myristyl Myserate                   2
    Dipalmiotyl Hydroxyproline    1
    Squalane                                 3
    Caprylic triglyceride                5.5

    PHASE C

    Glycerin based extract             5
    Oil based extract                   0.5
    Xylitylglucoside (and) Anhydroxylitol (and) Xylitol  1.5
    Heat sensitive oil                    3
    Vit E                                       0.2

    PHASE D

    HA powder                              0.1
    water                                       5

    PHASE E

    Dehydroacetic acid & Benzyl alcohol  1

    Ph~5


    Observations and thoughts:

    I’ve received an amazing product with an outstanding sensorial profile (wish I wouldn’t have to change anything!). The product passed freeze/throw 5 cycles and centrifuge. It remained stable for only 10 weeks at 45 degrees. I’ve been using/testing it myself for months and no changes to smell, appearance  (I know that it needs a PET test, however fist wanted to see how it behaves in normal conditions).

    After doing some more research on preservation systems I realized that I am missing a chelator and that Dehydroacetic acid & Benzyl alcohol wouldn’t be effective against mold.

    So…I decided to add sodium phytate as a chelator and experiment with 3 different preservation systems:

    1. Dehydroacetic acid & Benzyl alcohol at 1% + 0.2% potassium sorbate as a booster
    2. Sharomix 705 (Benzoic Acid, Sorbic Acid, Dehydroacetic Acid, Benzyl Alcohol) at 0.8% (as instructed by the supplier)
    3. Sodium Levulinate, Sodium Anisate, Glycerin, Aqua at 4% + 1% pentylene glycol as a booster

    Adding sodium phytate to the water phase reduced the viscosity of the final product when I was working with preservation system 1 and 2. 
    However, adding sodium phytate to the cool down phase didn’t have any impact on viscosity.
    When I was testing preservation system 3 I added sodium phytate and pentylene glycol to the water phase and preservative to the cool down phase (resulting in decreased viscosity). Adding preservative to the water phase was completely destabilizing the system and there was a formation of jelly-like weird structures.

    I am aware that Montanov 202 isn’t electrolyte tolerant but I was thinking that adding Montanov 68 +MM+CP+gum will help to reinforce it.

    So..to build the viscosity up I added 2% of glyceryl stearate, however, it didn’t make any change and I was skeptical about adding any more in order to preserve an amazing sensory profile of the product.

    What do I need to achieve:

    1. Increase emulsion stability so it can remain stable at 45 Degrees for at least 12 weeks.
    2. Increase emulsion tolerance to electrolytes (i know I could change the emulsifier but I would like to know what could be done here first).

    My questions to you guys:

    1. Do you think that adding small amounts of anionics eg. GSC or SSG would help with stability issues and boost the tolerance for electrolytes? Or maybe there is something else I could try?
    2. Which one of them has lighter skin feel from your personal experience? 
    3. Do you think that sodium phytate must be added to the water phase? Or adding it to the cool down phase would be also fine?

    I would be very grateful for constructive feedback, advice and help!
    Stay safe!
    Thanks

    ggpetrov replied 2 years, 9 months ago 3 Members · 7 Replies
  • 7 Replies
  • ggpetrov

    Member
    February 19, 2022 at 4:50 pm
    According to my understandings, the under eye cream should be something light and mostly fluid. Looking at your formula it looks quite heavy. I think you have too much waxy esters, also too much emulsifiers. In general your fat phase looks quite inadequate. I don’t see any basic humectants in your formula, such as Glycerine or Propylene Glycol.
    I haven’t used these emulsifiers, but I have used Simulgreen 18-20 which was similar, and I didn’t like it at all. You can make a fantastic under eye cream by using more simple and basic emulsifiers such as Glyceryl Stearate Citrate, Glyceryl Stearate SE and many more.
    Regarding your preservation system, I think it’s quite problematic. First it is not sufficient to protect your product, and second this combination very often leads to viscosity issues. Also it requires a certain Ph to work properly.

  • Abdullah

    Member
    February 20, 2022 at 3:53 am

    Yes adding anionic surfactant helps stability. Also adding fatty alcohol and increasing solagum ax to ~5% helps.

    Chelating agents should be added to water at first.

    Montanov is more susceptible to microbes and this preservative is also not very effective. I prefer phenoxyethanol or DMDM hydantoin over benzyl alcohol and paraben or IPBC for fungi. 

  • goska007

    Member
    February 20, 2022 at 11:23 am

    @ggpetrov thank you for your answer. I agree that the formula may seem to be heavy but I don’t understand what do you mean by “inadequate”. Could you explain, please? I have 3 humectants in that formula: glycerine (phase C as it is heat sensitive extract), HA and Aquaxyl (Xylitylglucoside, Anhydroxylitol, Xylitol). I agree that Dehydroacetic acid & Benzyl alcohol on its own won’t protect the product so that’s why I am considering testing 3 different options: 1. Dehydroacetic acid & Benzyl alcohol at 1% + 0.2% potassium sorbate as a booster
    2. Sharomix 705 (Benzoic Acid, Sorbic Acid, Dehydroacetic Acid, Benzyl Alcohol) at 0.8% (as instructed by the supplier)
    3. Sodium Levulinate, Sodium Anisate, Glycerin, Aqua at 4% + 1% pentylene glycol as a booster

    I am intending to keep the current pH which is ~5. All of the listed preservation systems will work well in this pH. 

  • goska007

    Member
    February 20, 2022 at 11:26 am

    @Abdullah thank you for your answer. I will try to add an anionic surfactant (GSC or SSG) then. Where did you get that information from about Motanov being more susceptible to microbes please? 

  • Abdullah

    Member
    February 20, 2022 at 1:41 pm

    This comparison

  • Abdullah

    Member
    February 20, 2022 at 1:42 pm

    This comparison

  • ggpetrov

    Member
    February 20, 2022 at 6:51 pm
    Don’t take it personally! By inadequate I meant that your fat phase doesn’t look very optimized. Cetyl palmitate is a great waxy ester, and I use it a lot, but it is quite occlusive. I think 3% is a way too much. I’d rather use it beyond 1%. MM is also great, but I found it a bit shiny on the face. Also it can hold the absorbtion of the emulsion if it’s used above certain concentration. I think you can play with certain esters, which can give a really nice haptics. I don’t use Soduim phytate, but I use Disodium EDTA in the hot water phase. I found that the Tetrasodium EDTA can induce some viscosity issues, so I don’t use it anymore.
    About the Montanov 202. I have used it in the past for a while. I have used it in the presence of Sodium PCA and Sodium Lactate, but I haven’t had a stability issues. It’s expensive, I don’t think it has matifiyng properties, also it is temperature sensitive. So, I didn’t like it and I don’t use it anymore. Seppic recomends to combine it with the Montanov 82, not 68.
    In your emulsion you have a lot of “bug food” - the hydrozole, the extracts, also the sugars. So your choice of a preservative isn’t adequate. As it was mentioned above, you should use more strong preservative system, and I don’t think that the lack of the chelating agent is your big problem.

    This “natural” preservative blends are quite unpredictable, I had a lot of viscosity issues with them, so I don’t recommend you to use them. Also if the viscosity drops, that means that your emulsifier don’t work anymore, and you can’t save the emulsion by increasing the gum, or waxes. You should change the approach.

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