What Is C12-15 Alketh-11?
C12-15 Alketh-11 is a man-made ingredient created by joining synthetic fatty alcohols that have 12 to 15 carbon atoms with small units of ethylene oxide. On average 11 of these units are attached to each fatty alcohol, which is why you see the number 11 in its name. The result is a clear to slightly hazy liquid that mixes well with both oil and water.
This nonionic surfactant first gained popularity in the 1970s when chemists looked for gentle alternatives to soap-based emulsifiers. Because it is produced from readily available petrochemical or plant-based feedstocks it offers formulators a stable and cost-effective option.
Manufacturing starts with the fatty alcohol blend. Under controlled heat and pressure ethylene oxide gas is added in measured steps until the target average of 11 units is reached. The process is closely monitored for purity then the material is filtered and tested before use in cosmetics.
You will most often find C12-15 Alketh-11 in facial cleansers, lotions, creams, sunscreens, sheet masks, makeup removers, leave-on conditioners, liquid foundations and anti-aging serums. It is valued for its ability to keep oils and water evenly mixed so products stay smooth and pleasant to use.
C12-15 Alketh-11’s Cosmetic Benefits/Uses
Formulators turn to this ingredient for one key reason that has several practical payoffs for your skin care routine.
Emulsifying: C12-15 Alketh-11 helps oil and water blend into a stable emulsion. This prevents separation so your cream or lotion has a uniform texture from the first pump to the last. A well-blended product spreads more easily, feels lighter on the skin and improves the delivery of moisturizing or active ingredients.
Who Can Use C12-15 Alketh-11
C12-15 Alketh-11 is generally suitable for all skin types, including oily, combination, normal and dry skin, because it is a mild nonionic emulsifier that neither strips natural oils nor leaves a heavy residue. Most sensitive skin users also tolerate it well, though anyone with a known sensitivity to polyethylene glycol derivatives should remain cautious.
The ingredient is produced from synthetic or plant-based raw materials without animal derivatives, which makes it appropriate for both vegans and vegetarians.
Current safety data suggests that products containing C12-15 Alketh-11 are acceptable for use during pregnancy and while breastfeeding because topical absorption is minimal. This is not medical advice, so pregnant or nursing individuals should review any skincare product with their healthcare provider to be safe.
C12-15 Alketh-11 does not increase photosensitivity and has no known issues when used alongside sunscreen or other daytime products.
Potential Side Effects/Adverse Reactions
Side effects from applying C12-15 Alketh-11 can vary from person to person. The points below list potential reactions, but they are uncommon when the ingredient is used correctly in a well-formulated product.
- Mild skin irritation: A small number of users may experience transient redness or stinging, especially on compromised skin
- Contact dermatitis: Rare allergic reactions can present as itching, rash or swelling in individuals who are sensitive to polyethylene glycol compounds
- Eye irritation: Direct contact with the eyes can cause watering or stinging until the product is rinsed away
- Increased penetration of other actives: As an emulsifier it can enhance the delivery of certain ingredients that may themselves be irritating in high concentrations
If you experience persistent discomfort, redness or swelling after using a product that contains C12-15 Alketh-11 discontinue use and seek medical advice.
Comedogenic Rating
Rating: 1/5
C12-15 Alketh-11 sits on the very low end of the comedogenic scale because it is a lightweight nonionic emulsifier that mixes readily with water and rinses away without leaving a heavy film. Its molecular structure is not the kind that easily lodges in pores or traps sebum, and typical use levels in formulas are small, often below 5 percent. For these reasons it is unlikely to trigger blackheads or whiteheads.
Suitable for acne-prone or breakout-prone skin in most cases.
Because this ingredient helps oil and water stay blended it can actually reduce the need for heavier waxes that might be more pore-clogging, giving it an indirect bonus for those watching their pores.
Summary
C12-15 Alketh-11 is mainly an emulsifier, meaning it keeps oil and water evenly mixed so creams lotions and cleansers stay smooth and effective. It does this by positioning its fatty alcohol tail in oils while its ethylene oxide head stays with water, forming a stable bridge between the two phases.
The ingredient is fairly common in modern skincare though not a headline act like hyaluronic acid or niacinamide. Formulators appreciate its reliability ease of use and cost efficiency, which is why it appears in everything from light gels to rich creams.
Safety data show a low risk of irritation or pore blockage for most users, making it a dependable choice across skin types and life stages. Still, skin can be unpredictable so it is smart to patch test any new product that contains C12-15 Alketh-11 before applying it widely.