What Is Sd Alcohol 27-B?
Sd Alcohol 27-B is a type of denatured ethyl alcohol. It starts as pure ethanol, usually produced by fermenting and distilling natural sources such as corn, sugarcane or grain. To make it unsuitable for drinking, manufacturers add a small amount of a denaturant, creating “Alcohol Denat.” and giving it the regulatory name Sd Alcohol 27-B. This step lets companies use the alcohol in cosmetics without the beverage taxes that apply to drinkable spirits.
The cosmetic industry has turned to denatured alcohol since the early 1900s because it evaporates quickly, mixes well with water and oils and helps other ingredients penetrate the skin’s surface. Modern production is highly controlled: once the ethanol is distilled to a high purity, the approved denaturant is blended in, then the liquid is filtered and tested for consistency before shipment to formulators.
You will see Sd Alcohol 27-B in many quick-dry or refreshing products. Common examples include facial toners, setting sprays, aftershaves, hair sprays, gels, lightweight lotions, clay or peel-off masks, anti-blemish spot treatments and fragrances. Its fast evaporation and clean feel make it a favorite when a product needs to leave no residue.
Sd Alcohol 27-B’s Cosmetic Benefits/Uses
Formulators rely on Sd Alcohol 27-B for several practical reasons that improve product performance and sensory feel.
- Astringent – Helps temporarily tighten skin and reduce the look of pores, giving a fresh matte finish that many people appreciate in toners or post-shave products
- Solvent – Dissolves fragrance oils, plant extracts and film formers so they stay evenly distributed, ensuring a clear stable formula that delivers actives uniformly
- Viscosity Controlling – Thins heavy formulations, allowing sprays and gels to spread easily and dry fast without a sticky after-feel
Who Can Use Sd Alcohol 27-B
Sd Alcohol 27-B is generally best suited to normal, combination and oily skin because its quick evaporation leaves a lightweight finish and can cut excess surface oil. Very dry or easily irritated skin may find frequent use dehydrating since the alcohol can pull water out of the stratum corneum, so those users should look for formulas balanced with humectants or emollients.
The ethanol used to make Sd Alcohol 27-B is typically fermented from plant sources like corn or sugarcane and the denaturants are synthetic, so the ingredient is considered vegan and vegetarian friendly.
No specific warnings exist for topical use during pregnancy or breastfeeding. Systemic absorption is minimal due to the rapid evaporation of the alcohol, yet this is not medical advice and anyone who is pregnant or nursing should have a doctor review any product they intend to use.
Sd Alcohol 27-B does not cause photosensitivity and will not make skin more prone to sunburn. Standard daily sun protection is still advised for overall skin health.
Potential Side Effects/Adverse Reactions
Reactions to topical Sd Alcohol 27-B vary between individuals. The following points list potential side effects, though most people will not notice any problems when the ingredient is used at normal cosmetic levels in a well formulated product.
- Dryness – excessive evaporation can strip moisture leading to a tight or rough feel
- Stinging or burning – may occur on freshly shaved skin or open blemishes
- Redness or flushing – short term vascular response in sensitive skin
- Itching or prickling – mild irritation that subsides after product has dried
- Exacerbation of eczema or rosacea – compromised skin barriers can react more strongly
- Contact dermatitis – rare allergic response to the denaturant portion rather than the ethanol itself
- Flaking or peeling – chronic overuse may disrupt the lipid barrier causing visible shedding
If a negative reaction appears, stop using the product and consult a healthcare professional for guidance.
Comedogenic Rating
Rating: 0 / 5. Sd Alcohol 27-B flashes off the skin within seconds, leaving no oily or waxy residue that could lodge in pores. Its low molecular weight and rapid evaporation make it incapable of forming the kind of film that traps dead cells or sebum, so it is classified as non-comedogenic. Because of this, it is generally considered fine for people who are prone to acne or breakouts. One point to keep in mind is that excessive dryness can sometimes prompt the skin to produce more oil, which may indirectly aggravate blemishes in a small subset of users, but the alcohol itself does not clog pores.
Summary
Sd Alcohol 27-B works mainly as an astringent, solvent and viscosity controller. Its high volatility tightens the surface of the skin for a brief matte effect, dissolves fragrance oils and actives so they stay evenly dispersed, and thins thick gels or sprays so they glide on lightly and dry almost instantly. Thanks to these attributes it shows up in everything from toners and setting mists to hair sprays and fragrances, making it one of the most common functional alcohols on ingredient lists. Despite its popularity, some consumers seek alternatives because frequent use can be drying, especially on sensitive or very dry skin.
When used at normal cosmetic levels Sd Alcohol 27-B is regarded as safe for topical application, with most concerns centering on dryness rather than serious irritation or toxicity. As with any new skincare ingredient it is wise to do a small patch test when trying a product that contains it, just to confirm personal tolerance.