Bio-Collagen Real Deep Mask

The base most products are built on. It carries the other ingredients and has no safety concern.

A humectant that draws water into the skin. One of the best-studied, best-tolerated ingredients in personal care.

A synthetic polymer used to thicken and stabilize cosmetic formulas. The polymer chains are too large to penetrate skin; graded safe by the Cosmetic Ingredient Review and widely used in rinse-off and leave-on products.

A form of vitamin B3 used to support a more even-looking tone and a comfortable barrier. Well tolerated at cosmetic levels.

A light, low-odor glycol used as a solvent and humectant, extremely common in Korean toners and essences. It has a low reported irritation rate and is graded low concern in published assessments.

A humectant naturally derived from sugar beets that helps skin draw in and hold water; it has a long history of safe use with no meaningful irritation or sensitization concerns.

A preservative and antioxidant that helps prevent microbial growth and oxidative degradation in formulas. Published assessments support its use at cosmetic levels.

A glycol used very widely in Korean and Western skincare as a lightweight humectant, solvent, and gentle preservative-booster, often in place of traditional preservatives. It has a low reported irritation rate at use levels and is graded low concern in published assessments.

Caprylyl glycol is a plant-derived humectant that also has mild antimicrobial properties, so it is commonly paired with other preservatives to allow lower overall preservative levels. Available data do not point to meaningful irritation or sensitization concerns at typical use levels.

A disaccharide (table sugar) that acts as a humectant to improve skin hydration and is a naturally occurring component of the skin barrier. It is well established as safe for topical cosmetic use with no known hazards.

A soothing, skin-conditioning compound (also found in comfrey root) commonly added to calm and hydrate irritated or sensitive skin. It has a long history of safe use with very low irritation potential.

A mild plant-derived emulsifier combining polyglycerol and lauric acid. Used in gentle formulas to blend oil and water phases; well tolerated across skin types at cosmetic concentrations.

A glycerin derivative used as a skin conditioner and preservative booster, often paired with phenoxyethanol to allow lower total preservative levels. It has a low irritation and sensitization profile in safety reviews.

A yeast ferment byproduct rich in polysaccharides and amino acids, used for hydration and skin conditioning. Published research suggests it supports skin texture and is well tolerated in cosmetics.

A naturally occurring nucleoside used in anti-aging formulas, often marketed for smoothing the look of fine lines. It has a low irritation profile and no established hazard at cosmetic use levels.

A chelating agent that binds trace metal ions to keep formulas stable and preservatives working properly. It is not a functional skincare "active" and only a very small amount is used, with minimal skin penetration expected.

A hydrosol from damascena rose flowers, used as a skin toner and fragrance. Rose can trigger allergic contact dermatitis in sensitive individuals, though the hydrosol form is generally well tolerated. People with a history of plant sensitivities should patch test.

A lightweight humectant and solvent similar in role to propylene glycol, used to carry actives and give lotions a lighter feel. CIR has reviewed it and considers it safe as used in cosmetics.

A salt form of glycyrrhizic acid, a compound from licorice root prized for soothing irritated skin. It is well tolerated at cosmetic levels and has a long history of use in skincare formulations.

A broken-down form of hyaluronic acid with smaller molecules intended to penetrate more deeply into the skin. It functions as a humectant and is well tolerated, with the same safety profile as standard hyaluronic acid.

A metabolite produced through fermentation of milk by Lactobacillus bacteria, valued in skincare for humectant and antioxidant properties. It is documented in cosmetic formulations as well tolerated, though people sensitive to fermentation byproducts or lactic acid may want to patch test.

An antioxidant that helps protect a formula and condition skin. Well tolerated.