Concentration Limits4 min read
AHA Leave-On Concentration Limits Explained for Makers
The alpha hydroxy acid leave-on ceiling, why pH matters alongside it, and why a sun warning usually rides along.
May 7, 2026Read
Tagged ph
Concentration Limits3 min read
Benzoic Acid and Sodium Benzoate Limits Tied to pH
Why sodium benzoate's preservative ceiling and its actual effectiveness both come down to your formula's pH, not just the percentage on the label.
March 18, 2026Read
Concentration Limits3 min read
Glycolic Acid Percentage Where a Peel Stays Cosmetic
Where the concentration and pH line sits between an at-home glycolic acid product and something that crosses into professional-peel territory.
March 9, 2026Read
Ingredient Guides4 min read
Potassium Sorbate: Why This Preservative Needs a Low pH
Potassium sorbate (CAS 24634-61-5) only works below a certain pH. Here's the chemistry, the pairing options, and where it falls short alone.
January 29, 2026Read