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Trying to replicate 2% BHA Liquid Exfoliant product
I’m trying to do something like PC’s 2% bha product. it’s one of their best sellers and i personally like the product. only thing, i think its expensive.
interestingly, it has only 8 ingredients.
Water
Methylpropanediol
Butylene Glycol
Salicylic Acid
Polysorbate 20
Camellia Oleifera Leaf Extract
Sodium Hydroxide
Tetrasodium EDTA
How they manage to solubilize 2% salicylic acid in this water-thin solution? or do they use water-soluble salicylic acid? -
8 Replies
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Salicylic acid is soluble in water-glycol (methylpropanediol, butylene glycol) mixtures. The more SA, the more glycol. You’ll have to try.I’d say that polysorbate 20 is in there simply to lower surface tension which makes the liquid feel more liquid and will more readily wetten skin. Depending on the leaf extract, it might help with its dissolution too.Because they use tetrasodium EDTA, some sodium hydroxide is needed to bring pH down.Meaning, for a first trial, all you need is water, glycols of your choice, and SA. -
There is no such thing as “water-soluble salicylic acid”, but there is a product that is a complex of Salicylic Acid and Acacia Sengal Gum from BASF that is readily water soluble, but expensive realtive to SA.
You will need on the order of 30% glycols (Methylpropanediol + Butylene Glycol) to keep the SA from crystallizing. Add the SA to the Glycols at 70C or so, stir until dissolved, then add to the hot water phase and let it cool down while stirring.
I would ditch the Polysorbate and instead add Cocoamidopropyl Dimethylamine which will help further dissolve the SA and add 1% Sodium Citrate for good measure.
Finally, adjust the final pH of your concoction to 3.5 - 4.0
Although this is not marketed as such, it is effectively an OTC Acne drug product.
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You guys are amazing! Thank you for these tips. I will try and update it here❤
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@MarkBroussard The usage rate of this BASF SA+ acacia gum is up to %3 and SA is up to %2. So if i use %2 SA with %1 acacia gum, would it be the same as this product from BASF?
I mean in solubility. -
No, the BASF product is a complex of SA with Acacia Gum that enhances the solubility of SA in water and creates a slow release of SA. In fact, it is completely water soluble.
Simply adding uncomplexed SA and Acacia Gum as separate ingredients will not be equivalent to the BASF product.
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@MarkBroussard Thanks
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MarkBroussard said:
@raiyanaThere is no such thing as “water-soluble salicylic acid”, but there is a product that is a complex of Salicylic Acid and Acacia Sengal Gum from BASF that is readily water soluble, but expensive realtive to SA.
You will need on the order of 30% glycols (Methylpropanediol + Butylene Glycol) to keep the SA from crystallizing. Add the SA to the Glycols at 70C or so, stir until dissolved, then add to the hot water phase and let it cool down while stirring.
I would ditch the Polysorbate and instead add Cocoamidopropyl Dimethylamine which will help further dissolve the SA and add 1% Sodium Citrate for good measure.
Finally, adjust the final pH of your concoction to 3.5 - 4.0
Although this is not marketed as such, it is effectively an OTC Acne drug product.
I was recently looking into this product and noticed there is no preservative. The pH is 3.2-3.8 and we assume the glycol input is around 30%, but I am wondering if this is really enough for the product to be self preserving. I am a bit of a germophobe and always like to be on the safe side and it’s bugging me if adding a tiny bit of preservative here would be a good precaution measure or simply unnecessary.
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…but I am wondering if this is really enough for the product to be self preserving.
You don’t wonder, you prove it from testing, usually through an outside lab. If anyone ever asks, “is this preservative strong enough or effective enough” the answer is always to look at the test results. They should be tested objectively, ESPECIALLY here where they are using low Aw to assist in preservation.
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