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BTW, can you share the ingredient list?

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Your suspects bring to my mind an old case:

https://www.ncbi.nlm.nih.gov/pubmed/16286743

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Just some tiny imprecisions  , thank you for your time!

In an other blog i’ve found something that seams the opposit of what originaly stated by Deciem:
”  some HA products at higher pHs (sometimes labelled as “buffered products”) are said to be time-release – instead of being able to absorb all the free acid straight away, some of the HA sits on top of the skin and slowly turns into absorbable free acid over time. This has the advantage of decreased irritation – both from too much HA, and from the low pH.“

Bill? Hope you are not mad at me throwing here whatever I find on the net

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I understand that the irritant potential of a salt is due, at least, to its crystallization on the surface of the skin, so pH>pKa = more salt = more irritation potential.

 The more salt you have in your acid, the less potent it is and potentially the more irritating it can be. This ‘irritation’ reaction should send a red flag to the professional aesthetician to check out the AHA product they are using to ensure the normal “erythema” end-point benchmark is attributed to acid activity or abnormal salt irritation. For this reason alone this fact is important to know your pKa and pH value to ensure your AHA peel is correctly formulated. If a manufacturer will not provide you the pH of the peel you use, change suppliers. 

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This is the explanation I just received from Deciem:

Sodium lactate has a high molecular weight. Therefore, it would stay on the skin and not penetrate which can be irritating.

Experts, do you agree? Thank you

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I’m the less qualified in this forum, but it’s right here that I learnt that ultramarine in pigments may turn the final product to smell like hell. A pH problem.

Occasionally, ultramarine blue is used in products for very dark complexions, as long at the pH is above 7. Exposure to acid causes the evolution of hydrogen sulfide

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Not to my knowledge. I really do not understand, Deciem doesn’t need any fancy sentence to sell his products. http://theordinary.com/product/rdn-lactic-acid-10pct-ha-2pct-30ml

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Thank you DrBob. I’ll never stop learning

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vjay I disperse pigments in a bit of oil, then I add a solubilizer like PGE-10 laurate and then in the oil fase.

I do use carbopol ultrez 21 and 30 with titanium Dioxide along with xanthan gum , but in o/w emulsions.

Milla I use both thickeners you mentioned, but never together, in what ratio do you recommend to use them? Thank you

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I learnt to disperse oxide pigments and TO2 in a bit of solubilizer for my BB creams, I was given the full explanation that has obviously to do with the surface tension.

I use it in o/w, don’t know if it works for w/o as well.

I would be nice to here your opinion.

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If I’m not wrong I learnt about this study http://www.nyscc.org/cosmetiscope_archive/backissues/Cosmetiscope_01.2007.pdf

in this forum.

“It has been reported that urea is released more quickly and in a higher concentration from oil-in-water (O/W) emulsions than from water-in-oil (W/O) emulsions. Even after a long penetration period, most of the urea is found in the upper layers of the stratum corneum. The release of urea from W/O emulsions takes longer, but it penetrates in greater amounts into the skin and is more evenly distributed.”

I guess the correct answer to your question is: it depends.

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Carbopol ultrez 30 can be the good choise. I’m using it with panthenol and works well.