What Is Alcohol Denat. Sd Alcohol 37?
Alcohol Denat. Sd Alcohol 37 is a form of ethyl alcohol that has been “denatured,” meaning a small mix of other ingredients has been added to make it unsuitable for drinking. In this case the denaturants are eucalyptol, thymol and menthol, three fragrant compounds that not only discourage consumption but also add a fresh, minty scent. The base alcohol is the same ethanol produced by fermenting and distilling sugar or grain sources. After purification, measured amounts of the three denaturants are blended in following the guidelines laid out in U.S. regulation 27 CFR 21, which makes the finished liquid exempt from beverage alcohol taxes.
The cosmetic industry turned to denatured alcohol many decades ago as a reliable way to get the rapid evaporation, clean feel and solubility of ethanol without the regulatory hurdles tied to drinkable spirits. Sd Alcohol 37 in particular gained favor because its menthol-eucalyptol-thymol combo leaves less of the harsh chemical odor found in other denatured blends. Today it shows up in a wide range of beauty products where a quick-dry, weightless finish is important: facial toners, setting sprays, liquid or pen-style eyeliners, fast-dry nail color, hair sprays, aftershaves, deodorant sprays, blemish treatments and certain peel-off masks.
Alcohol Denat. Sd Alcohol 37’s Cosmetic Benefits/Uses
Its role in formulas is straightforward yet valuable: as a solvent it dissolves a variety of ingredients that might otherwise separate, helping create clear, stable solutions. Because ethanol flashes off the skin within seconds, it leaves behind the beneficial actives without a heavy or greasy residue. This makes Sd Alcohol 37 especially useful in products designed to feel light, set quickly or provide an instant refreshing sensation.
Who Can Use Alcohol Denat. Sd Alcohol 37
Products with Alcohol Denat. Sd Alcohol 37 tend to feel weightless and quick drying, which suits normal, combination and oily skin. Those with very dry, sensitive or compromised skin barriers may find the fast evaporation too stripping because it can pull water from the surface and leave the skin feeling tight.
The alcohol itself is usually obtained by fermenting plant sugars and the denaturants eucalyptol, thymol and menthol are either plant derived or synthetically reproduced, so the finished ingredient contains no animal substances and is generally considered appropriate for both vegans and vegetarians.
Topical use while pregnant or breastfeeding is not known to pose special risks, as the alcohol evaporates quickly and systemic absorption is minimal. This is not medical advice and anyone who is pregnant or nursing should show any planned skincare product to a healthcare professional before using it just to be safe.
Alcohol Denat. Sd Alcohol 37 does not increase photosensitivity so it will not make skin more prone to sunburn. Because it can have a cooling sting on open cuts or freshly exfoliated skin it is best applied only to intact areas.
Potential Side Effects/Adverse Reactions
Reactions to topical Alcohol Denat. Sd Alcohol 37 differ from person to person. The points below outline potential issues although most people will not experience them when the ingredient is used correctly in a well formulated product.
- Dryness or tightness caused by rapid evaporation drawing moisture from the skin surface
- Redness stinging or burning in those with sensitive skin
- Flakiness or peeling when used alongside other exfoliating or drying agents
- Temporary rebound oiliness as sebaceous glands respond to surface dehydration
- Allergic contact dermatitis triggered by menthol eucalyptol or thymol in susceptible individuals
- Eye irritation or watering if aerosol or spray formats are used too close to the eye area
If any troubling reaction occurs stop using the product and consult a healthcare professional for advice.
Comedogenic Rating
Rating: 0/5 (non-comedogenic)
Alcohol Denat. Sd Alcohol 37 is highly volatile so it evaporates almost as soon as it hits the skin and does not sit in pores long enough to block them. The molecule is small and water-like which means it cannot form the waxy films typically linked with breakouts. For that reason it is generally suitable for acne-prone or congestion-prone skin types.
Because it can temporarily strip surface oils some users see a short-term reduction in shine, although others may experience rebound oil production later. This oil fluctuation relates to dryness rather than pore blockage so it does not affect the ingredient’s low comedogenic profile.
Summary
Alcohol Denat. Sd Alcohol 37 acts mainly as a solvent that dissolves fragrances, resins and active ingredients then flashes off to leave a light clean finish. Its rapid evaporation helps formulas set quickly, keeps sprays and toners crystal clear and provides an instant cooling feel.
The ingredient is popular in fast-dry hair sprays, setting mists, liquid liners and aftershaves yet it also draws criticism from those who avoid drying alcohols. Overall it remains a staple in many mainstream formulations because few other solvents match its speed, clarity and low cost.
Safety studies and long consumer experience show it is low risk for most users although people with very dry or sensitive skin may prefer to limit frequent use. As with any new cosmetic it is wise to patch test a product containing Alcohol Denat. Sd Alcohol 37 to check personal tolerance before applying it widely.