The Ordinary Glycolic Acid 7% Toning Solution - Ulta Beauty

"Glycolic Acid is an alpha hydroxy acid that exfoliates the skin. This 7% toning solution offers mild exfoliation for improved skin radiance and visible clarity, while also improving the appearance of skin texture with continued use.
This formula contains a studied Tasmanian Pepperberry derivative to provide comforting benefits to the skin. It is further supported with inclusion of ginseng root and aloe vera for both visible radiance and soothing benefits.

This pH of this formula is approximately 3.6 and Glycolic Acid has a pKa of 3.6. The pKa is the most important aspect to consider when formulating with acids as it implies acid availability. When pKa is close to pH, there is an ideal balance between salt and acidity, maximizing the effectiveness of the acid and reducing the potential of developing irritation. Higher pH values in such a case would increase the concentration of salt, which counter-intuitively would make the formula even more irritating than if the formula was more acidic.This formula contains a studied Tasmanian Pepperberry derivative to help reduce irritation associated with acid use. This derivative is of plant origin and varies in colour seasonally and this colour variation may be apparent in the formula from time to time. The formula is further supported with inclusion of ginseng root and aloe vera for both visible radiance and soothing benefits.
Contraindications: This formula should not be used on sensitive, peeling or compromised skin. Please refer to additional sun protection note and other warnings in provided Directions.
Notes:
The Tasmanian Pepperberry derivative included in this formula is of plant origin and as such will vary in colour seasonally. This colour variation may be apparent in the formula from time to time.
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