What Is Sd Alcohol 39?
Sd Alcohol 39 is the cosmetic name for denatured ethyl alcohol. The ethanol at its core is usually produced by fermenting and distilling crops such as corn, sugarcane or grain. To prevent it from being consumed, manufacturers add small amounts of denaturants like tert-butyl alcohol or bittering agents, creating a liquid that keeps ethanol’s useful properties while making it unfit to drink.
Alcohol has been a household solvent and antiseptic for centuries, but it was during the early 1900s that denatured versions were formalized and approved for commercial use. Cosmetic chemists soon adopted Sd Alcohol 39 for its fast evaporation and clean feel, making it a staple in modern beauty labs.
Production begins with the fermentation of plant sugars into ethanol, followed by repeated distillation for purity. After this, the alcohol is blended with the chosen denaturants, filtered and tested to meet government and industry standards before it is shipped to cosmetic manufacturers.
You will most often see Sd Alcohol 39 in lightweight formulations that need quick dry-down or oil-cutting power. Typical examples include facial toners, clarifying mists, setting sprays, perfumes, hair sprays, gel moisturizers, spot treatments and peel-off masks.
Sd Alcohol 39’s Cosmetic Benefits/Uses
In formulations Sd Alcohol 39 delivers several performance perks:
- Astringent Helps tighten the look of pores, remove excess surface oil and leave skin with a refreshed matte finish, making it a popular choice in toners and acne-prone products
- Solvent Dissolves oils, resins and active ingredients so they distribute evenly, aids in creating clear solutions and helps fragrances bloom on the skin or hair
- Viscosity Controlling Thins heavy formulas for a lighter texture and faster absorption, improving spreadability and reducing the greasy feel of certain emulsions
Who Can Use Sd Alcohol 39
Sd Alcohol 39 is generally best suited to oily, combination and normal skin because its quick evaporation and oil-cutting nature help reduce shine and leave a light finish. People with very dry or easily irritated skin may find it too stripping since repeated exposure can pull moisture from the surface and weaken the skin barrier, which might lead to tightness or flaking. Those with rosacea or eczema should approach formulas containing high levels of Sd Alcohol 39 cautiously for the same reason.
The ethanol used in Sd Alcohol 39 is plant fermented and the denaturants are synthetic, so the ingredient is compatible with vegan and vegetarian lifestyles. No animal-derived substances are typically involved in its manufacturing process.
Current research shows no specific concerns for topical Sd Alcohol 39 during pregnancy or while breastfeeding when used in standard cosmetic levels. Still, this is not medical advice and anyone who is pregnant or nursing should ask their doctor before adding new skincare products.
Sd Alcohol 39 does not make skin more sensitive to sunlight and does not require extra sun protection beyond the daily SPF already recommended. It is also odorless once dry, so it will not clash with fragrance-free routines.
Potential Side Effects/Adverse Reactions
Reactions to Sd Alcohol 39 can differ widely from person to person. The points below outline potential side effects that could occur, but most users will not experience them when the ingredient is used correctly in a well-formulated product.
- Surface dryness or tightness
- Transient stinging on compromised or freshly exfoliated skin
- Redness or mild burning sensation in sensitive complexions
- Flaking or rough texture from repeated overuse
- Contact dermatitis in individuals allergic to alcohols or certain denaturants
- Exacerbation of rosacea flare-ups due to barrier disruption
- Increased penetration of potent actives that may heighten irritation
If any discomfort, rash or persistent irritation develops stop using the product and consult a qualified healthcare professional.
Comedogenic Rating
Rating: 0 / 5
Sd Alcohol 39 is a lightweight volatile liquid that flashes off the skin rather than sitting on the surface. Because it leaves no oily or waxy residue to clog pores its likelihood of triggering comedones is essentially zero. For this reason it is generally considered suitable for people who are prone to acne or frequent breakouts.
One extra point to note is that Sd Alcohol 39 can enhance penetration of other ingredients. If a formula also contains oils or heavy emollients their comedogenic potential may effectively rise even though the alcohol itself remains non-pore-clogging.
Summary
Sd Alcohol 39 acts as an astringent, solvent and viscosity controller. Its small molecular size and rapid evaporation pull excess oil away for a temporarily tighter feel, dissolve fragrance oils and actives so they spread evenly and thin out thick textures to give products a weightless finish.
The ingredient is popular in toners, setting sprays, perfumes and other quick-dry products because it offers instant lightness at a low cost. Some consumers avoid it due to concerns about dryness but many brands still rely on it for its unique performance benefits.
Studies and decades of use show Sd Alcohol 39 is safe for topical application at standard cosmetic levels. While irritation is uncommon in well-balanced formulas everyone’s skin is different so patch testing any new product is a smart precaution.