Let's learn about the exfoliating agent PHA.

PHA Ran ,

It is a next-generation peeling ingredient newly created amidst the AHA and BHA craze, composed of gluconolactone, which is highly effective for exfoliation and skin texture management, and lactobio acid, which has the effect of dissolving the stratum corneum and waste products.

As a water-soluble substance identical to AHA, it not only makes the stratum corneum smooth and flexible but also prevents clogged pores and helps repair damaged epidermal cells.

Nevertheless, the decisive reason why it causes less skin irritation compared to AHA lies in the difference in molecular structure size. While AHA penetrates the skin and causes stinging, PHA, with its larger molecular structure, is absorbed slowly, resulting in relatively less irritation. 

In addition, it strengthens the skin barrier with natural antioxidant ingredients that attract water and enhance hydration, while also providing anti-aging effects such as reducing fine lines and improving complexion.

Source: Vogue

It is effective for exfoliating dry combination skin, so I recommend it for sensitive skin that is easily irritated.