Common Name(s): 1,3-butylene glycol,1,3-bg,butane-1,3-diol

CAS Number: 107-88-0

DESCRIPTION

What It Does: Provides humectant and solvent functionality in the most widely used cosmetic diol.

Why It's Used: The k-beauty standard diol — 1,3-bg is present in the majority of korean cosmetics as the standard humectant/solvent, providing moisture retention, active solubilisation, and elegant texture.

How It Works: Two hydroxyl groups provide humectant water binding. solvent for fragrances, preservatives, and actives. mild antimicrobial boosting from diol structure. k-beauty standard for layered toner application (7-skin method).

Typically Found In: K-beauty serums,moisturisers,virtually universal in korean cosmetics

TECHNICAL DETAILS

Primary Category: Functional ingredient – humectant

Secondary Functions: Tewl reduction,skin plumping

Application Areas:

Typical Concentration Range: 1%–20%

SOURCING & ETHICS

Vegan Status: Yes – synthetic

Halal Status: Yes

Source Notes: Synthetic or naturally derived. excellent aqueous solubility. [audit 2026-07-29 rev2: status downgraded on audit. determination requires shariah-panel sign-off.]

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; suitable for all skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Ceramides,emollients,occlusives,glycerin,hyaluronic acid

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

1,3-bg's dominance in korean cosmetics reflects korean mfds regulations more explicitly limiting propylene glycol in certain product types, driving formulators to adopt 1,3-bg as the standard diol with the lighter, less-tacky character particularly suited to k-beauty's layered application tradition.

Last Verified: 2026-03-12

Primary Sources: Cosing database,cir safety assessment