SD Alcohol 40-B: what it is in skincare
⚡ Quick answer: A specially denatured alcohol that helps products feel weightless but can be drying for some skin.
A specially denatured alcohol that helps products feel weightless but can be drying for some skin.
What it does
Function: solvent (drying alcohol). Solvents dissolve and carry other ingredients. Some lightweight alcohols also give a fast-absorbing finish (a sensitivity point for some skin).
Heads-up flags
- alcohol-drying
- sensitive-skin-caution
How to spot it on a label
On a Korean product's INCI list, look for SD Alcohol 40-B. Ingredients are listed high-to-low by amount, so its position hints at how much is in the formula. See all solvents →
Explore the full K-beauty hub →✍️ Written & reviewed by the KoreaPlus Editorial team — dermatologist-informed, cosmetic-science researched & source-cited. Last reviewed 2026-06-21.
General educational information using cosmetic structure-function wording — not medical advice. Always patch-test new actives. © KoreaPlus.