What Is Sodium C11-15 Alkyl Sulfate?
Sodium C11-15 Alkyl Sulfate is a surfactant made by attaching a sulfate group to a blend of synthetic alcohols that each have 11 to 15 carbon atoms, then neutralizing the mixture with sodium. The final powder or liquid is water soluble and has a strong ability to attract both oil and water, which is the key to its cleansing power.
This ingredient grew popular in the mid-20th century when manufacturers searched for alternatives to soap that would lather well in hard water. Advances in petrochemical processing and later plant based feedstocks made it possible to produce the even-chain alcohols needed for this sulfate, giving formulators a versatile and cost-effective cleanser.
Production usually starts with either petroleum fractions or natural oils such as coconut or palm. The chosen alcohols are first purified, then reacted with sulfur trioxide to create the sulfate ester. The acidic sulfate is neutralized with sodium hydroxide, filtered and spray-dried or left in solution depending on the intended use.
You will most often find Sodium C11-15 Alkyl Sulfate in rinse-off products where rich foam is a selling point. These include facial cleansers, body washes, hand soaps, bubble baths and shampoos. It may also appear in exfoliating scrubs, clay masks and toothpaste to enhance foaming and spreading.
Sodium C11-15 Alkyl Sulfate’s Cosmetic Benefits/Uses
In formulas, this ingredient plays one main role that leads to several practical benefits:
- Cleansing: Its surfactant nature lowers the surface tension of water so oils, dirt and makeup can be lifted from skin or hair and rinsed away. The result is a thorough, squeaky clean feel plus the rich lather many users expect from a wash product.
Who Can Use Sodium C11-15 Alkyl Sulfate
Most people with normal, oily or combination skin can use products containing Sodium C11-15 Alkyl Sulfate without issue because it rinses clean and does not leave a residue. Those with very dry, eczema-prone or highly sensitive skin may find it too stripping since strong foaming agents can pull away needed lipids and leave skin feeling tight.
The ingredient is generally vegan and vegetarian friendly because the alcohols used today are typically derived from plant oils or synthesized from petrochemical feedstocks, neither of which involves animal by-products. Brands that are certified vegan should clearly state the source on their labels.
No data suggest special risks for pregnant or breastfeeding women using rinse-off products that include this surfactant. Still, this is not medical advice and anyone who is expecting or nursing should have a doctor review their personal care routine for extra peace of mind.
Sodium C11-15 Alkyl Sulfate does not increase photosensitivity, so there is no added need for sun avoidance beyond routine daytime sunscreen habits.
Potential Side Effects/Adverse Reactions
Reactions to topical Sodium C11-15 Alkyl Sulfate differ by individual and are uncommon when the ingredient is used at the concentrations typical of shampoos and body washes. The points below outline possible but unlikely effects.
- Skin dryness or tightness
- Transient redness or stinging on sensitive or compromised skin
- Contact dermatitis in individuals allergic to sulfate surfactants
- Eye irritation if the lather accidentally gets into the eyes
- Color fading in chemically dyed hair due to strong cleansing action
If you notice irritation or any unexpected reaction stop using the product and consult a healthcare professional for guidance.
Comedogenic Rating
Rating: 1 / 5
Sodium C11-15 Alkyl Sulfate is highly water soluble and rinses off completely so it is unlikely to sit on skin long enough to block pores. Its molecule is designed to lift away oil rather than add any, which keeps the risk of comedones low. The mild irritation some people experience comes from its cleansing strength, not from pore clogging.
Because of this low rating products with this surfactant are generally suitable for people who are prone to acne or breakouts, especially when used as a rinse-off cleanser.
As with any foaming agent the overall formula matters. Heavy oils, waxes or fragrances paired with it could still cause clogging so always consider the full ingredient list.
Summary
Sodium C11-15 Alkyl Sulfate is mainly a cleanser. Its dual love of oil and water lets it grab grime then rinse away clean taking makeup, sebum and dirt with it. This same action creates a satisfying foam that many users associate with effectiveness.
The ingredient is popular in everyday shampoos, body washes and face cleansers because it is affordable, easy to formulate with and delivers reliable lather. While trendier gentle surfactants have taken some market share, it still appears in countless mass-market and some premium products.
Safety data show it is well tolerated in rinse-off formats though very dry or sensitive skin may find it a bit stripping. Serious reactions are rare. As with any new product a quick patch test on a small area of skin is a smart habit to catch unexpected sensitivities before full use.