Home Cosmetic Science Talk Formulating syndet bar fine tuning

  • syndet bar fine tuning

    Posted by Robb on September 9, 2022 at 1:57 pm

    Good afternoon all,

    I am in the throws of fine tuning a syndet bar formula.

    I’m a Chemistry teacher and so my access to academic papers etc is somewhat limited, plus I do not have anyone to bounce ideas with.

    So, I have come to these discussion threads looking for advice.

    Progress to date:

    Ideal bar properties:
    -cleansing
    -conditioning
    -will not leave coloured/dry hair feeling dry and tangled

    formula:
    66 % SCI
    7% BTMS-25
    5 % cetyl alcohol
    2 % coconut oil
    2 % cocoa butter
    3 % stearic acid
    10 % CAPB
    1 % polyquaternium-7
    1 % jojoba oil
    1% phytokeratin
    0.3% mica
    2 % essential oil/fragrance oil

    Results
    -Bar remains ever so slightly squishable 1 week after pressing
    -Bar is pH 5.5
    -Hair strands do not feel dry after washing
    -Hair does not tangle during wash
    -Very, very slight static after drying (5/6 strands)
    -Hair feels slightly coated with a film after drying

    Evaluation
    -Look to remove or significantly decrease plant oils/butters. After reading these threads it struck me that these will be removed by the surfactant. I should have thought of this before, seems daft to add oils and remove them at the same time.
    -increase emulsifying wax %
    -Decrease polyquaternium-7 to 0.5 %.

    So, well done if you have read this far! 🙂

    I would be delighted to hear from someone who would be willing to discuss this further.

    Thanks.

    Robb replied 2 years, 2 months ago 6 Members · 8 Replies
  • 8 Replies
  • Syl

    Member
    September 9, 2022 at 9:13 pm

    If they are soft it means you have too much oil, reduce oil content and increase sci to 100%.

  • Squinny

    Member
    September 10, 2022 at 12:11 am

    Hi there I have never made but maybe check out some supplier sites for formulations to give you some more ideas like Aussie Soap Supplies: Solid Shampoo Bar with Argan Oil Tutorial (aussiesoapsupplies.com.au) - this is one but they have a few formulations.
     Also Humblebee&me has a number of different Shampoo Bars that may be useful to look at her formulations and video’s 🙂 How to Make Shampoo - Humblebee & Me (humblebeeandme.com).
    Also Making Cosmetic USA have some formulations and they have PDF’s you can download too Homemade Shampoo Formulas | Make Your Own DIY Shampoo with Recipes | MakingCosmetics
    And How to make a cocoa shampoo bar - Formula Botanica

    All the above are more for the home formulator. Have fun researching. Cheers

  • Robb

    Member
    September 10, 2022 at 3:03 pm

    Thanks for your feedback @squinny and @Syl, much appreciated!  :)

  • DRBOB@VERDIENT.BIZ

    Member
    September 10, 2022 at 3:55 pm

    increase stearic acid to 6-10% for bar firmness and after feel.You can also add free sodium isethionate 2-3wt %

  • luttie

    Member
    September 16, 2022 at 1:45 am

    I recommend you to start simple and add one ingredient per batch. I usually make 10~16g per batch so it is not too expensive. Also use the less expensive oil before the real fine-tunning, when you have a great formula that requires very few tweaks.

    I would start with only:
    Batch 1 (Please make small batches! like <20g!)
    SCI - 70%
    Cheap oil (coconut. I usually use sunflower) - 4%
    Butter - 5%
    CAPB 8%
    Cetyl Alcohol - 13%

    Batch 2 
    SCI - 52%
    Cheap oil - 4%
    Butter - 5%
    CAPB 8%
    Cetyl Alcohol - 31%

    In previous tests (using starches and cetearyl alcohol) I couldn’t see any difference comparing the version with ~50% and ~70% surfactants. So please try it yourself and see if your formula can be cheaper and still do the same job!

    It should take less than 30 minutes in freezer for each formula to be good enough to test.
    If you use starches (corn or tapioca) instead of some of the Cetyl/Stearic (like ~20% starches and ~5% stearic + cetyl) it becomes “ok” faster but can look rough (not well-finished).


    Then you can go adding 1 or 2 ingredients for each batch.
    Remove from the cheaper oil or butter to add oils and from SCI to add solids.
    BTMS is mostly cetearyl alcohol so you can change some of the Cetyl alcohol for it.

    Points:
    > Oils and butters will only fight with the oils in your hair for the surfactants attention, that’s true. But this is a solid product and the *feeling* is important. About ~5% butters and ~5% oils usually give me a bar that is quite hard but not a piece of stone lol. If I try to regulate the softness with glycerin, water or capb bad things may happen. More on that below.
    > Jojoba oil is VERY expensive. I recommend you to do at least the first tests with another cheaper oil and later try to incorporate jojoba.
    >more than 15% CAPB can make the bar quite sticky. This is much less important if you have quite some hardeners (cetyl/cetearyl alcohols or stearic acid total >20%).
    > I’ve seen bars with polyquat 7 (not mine though) so I know it is possible. 
    > Glycerin can mush bars very easily (I see you didn’t use it but still a good info). 
    In my tests there is also very little (not noticeable) difference in performance and final appearance substituting cetearyl for tapioca starch or corn starch in order to add up to 100%.

    Action:
    > Too sticky? Reduce glycerin or CAPB or Water
    > Too soft? Reduce oils and/or butters
    > Lacks foam? Reduce oils and butters, increase surfactant
    > Try one conditioning agent at time. Make one batch with BTMS, one with Polyquat 7 and one with both. Then compare. 
    > Reduce fragrance. I usually see it <1.5%. 

    By the way, what kind is your SCI? The powder version? There is a commercial version that is ~60% SCI and ~40% stearic acid.

    —-

    Here some formulas I found and saved for myself. Good luck!

    Handmade style shampoo bar (with starch) (Colonial Chem)

    Hor Pour shampoo bar (Colonial Chem)

    The file shampoo bar melt: I did it myself and hate it to this day because it is really sticky. It has a lot of glycerin. Polyquat 10 at only 0.2% (I didn’t use it because I don’t have it 😐  ).

    >>>>The file from Ajinomoto: There is a formula in page 25. Also each ingredient comes with a function that can help you to compare to your formulation. Guar quat at 0.8%.

    Note
    Many of the internet formulas just feel “meh”. Some are quite sticky and crumble easily. Some also can be very different because the location where the maker was is another one! I’ve seen bars that looked quite good because the person lived in places where the temperature is like ~20ºC. I livre in Brazil. We got up to 35ºC easily. Keep that in mind please.

    -

    Feel free to discuss it more if you can manage to understand my terrible english ::wink:

  • Robb

    Member
    September 18, 2022 at 11:47 am

    Wow, thank you so much for taking the time to write all that. I really appreciate it and I will take it all on board  :)

  • Cafe33

    Member
    September 18, 2022 at 10:53 pm

    Remove Polyquats from your formula. They will offer no added benefit and they tend to weaken the structure of your bar. In general, try to get closer to 70% in powdered surfactants. Drop oils and butters to 0.1% or less of each.  

  • Robb

    Member
    September 30, 2022 at 4:55 pm

    thank you  :)

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