I would like to share with you that betaine (trimethylglycine, not cocamidopropyl) works great in dissolving higher % of allantoin (and salicylic acid, but haven't tested that yet).
Since there is no hard data available, you'll need to experiment.
So far I've found that 3% betaine easily keeps 1% allantoin dissolved in my body lotion formula below. It's a light lotion that isn't greasy feeling and absorbs very quick.
Actually I wanted it to be a bit thicker, but I'm still waiting for Sepimax Zen™ , which I ordered from The Formulary in England. (Maybe the 1% caprylyl glycol is too high?)
It's because of the Lactil® in this formula that I can't use my Carbopol® Ultrez 10. I think the Ultrez 10 can handle that bit of chelator though, right?
BODY LOTION
Water Phase
Deionized water ad 100
2% Glycerin
0.2% Dermofeel® PA-3 (sodium phytate, aqua, alcohol)
2% Niacinamide
1% Allantoin
3% Betaine
0.5% Phenonip®
Oil Phase
5% Glyceryl Stearate + PEG 100 Stearate
2% Shea Butter
2% Cetyl Alcohol
2% Behenyl Alcohol
2% Lexfeel® 350 (Dipentaerythrityl Hexa C5-9 Acid Esters)
1% Isopropyl Myristate
4% Babassu Oil, refined
1% Caprylyl Glycol
0.2% Tocopherol (alpha)
0.5% Phenonip®
0.4% Xanthan Gum
Cool Down Phase
2% Cyclopentasiloxane
0.3% Bisabolol (alpha, natural)
3% Evening Primrose Oil, unrefined
5% Lactil® (Sodium Lactate; Sodium PCA; Glycine; Fructose; Urea;
Niacinamide; Inositol; Sodium Benzoate; Lactic Acid)
0.4% Fragrance (Sleeping Angels by Brambleberry)
Comments
You mean it's even ok with 5% Lactil®? (Sodium Lactate; Sodium PCA; Glycine; Fructose; Urea; Niacinamide; Inositol; Sodium Benzoate; Lactic Acid)
I don't know exactly how much elektrolytes it can deal with, but it would be awesome if it can handle the chelator + the Lactil!
It's a blend of humectants for hydration (N.M.F.).
@DRBOB@VERDIENT.BIZ
It's the max of the recommended dose (1-5%). Would you suggest a lower % for hydration?
I don't know the electrolyte sensitivity of the different carbomers and Evonik never uses more than 2% Lactil in their formula suggestions.
(I forgot to mention that betaine is very hygroscopic, I store it with silica bags)
Why not go for a much cheaper humectants?