What Is Bis-(C24-30 Alkyl/Butyl) Dimethicone?
Bis-(C24-30 Alkyl/Butyl) Dimethicone is a silicone based ingredient made by linking long chain alkyl or butyl groups to a dimethicone backbone. The result is a soft waxy polymer that combines the smooth glide of silicones with the cushy feel of plant like fatty chains. It is usually created through a controlled chemical reaction in which dimethicone is modified with high-carbon alcohols, then carefully purified to meet cosmetic standards. Silicones entered skin care in the 1950s for their silky texture, and over time formulators learned that grafting longer alkyl chains onto dimethicone improved its richness and staying power, leading to the launch of this specific version in the early 2000s. Today it can be found in rich face creams, night masks, lip treatments, high-end anti-aging serums, color cosmetics like foundations and primers, and protective hand lotions where a long-lasting, non-greasy cushion is desired.
Bis-(C24-30 Alkyl/Butyl) Dimethicone’s Cosmetic Benefits/Uses
In formulas this ingredient mainly serves as an emollient, meaning it softens and smooths the skin surface. Its long fatty chains help fill in microscopic gaps between skin cells, leaving a supple velvety finish while reducing moisture loss. Because it is heavier than classic dimethicone yet still non-occlusive, it delivers a comforting coat that feels luxurious without a sticky afterfeel.
Who Can Use Bis-(C24-30 Alkyl/Butyl) Dimethicone
This silky silicone wax suits most skin types, especially normal, dry or mature skin that craves extra cushioning. Its lightweight occlusive nature locks in moisture without feeling heavy so combination skin usually tolerates it too. Those with very oily or acne-prone skin may find the richer texture feels occlusive and could prefer lighter silicones, though many still use it without issue.
The molecule is fully synthetic and sourced from silica plus lab-made long chain alcohols, not animals, so it aligns with vegan and vegetarian values.
Current research shows no specific concerns for pregnant or breastfeeding women when the ingredient is used topically in cosmetics. This is not medical advice and anyone who is expecting or nursing should show any product they plan to use to their doctor to be certain it fits their personal situation.
Bis-(C24-30 Alkyl/Butyl) Dimethicone does not make skin more sensitive to the sun and has no known phototoxic effects. It is also fragrance free and non volatile so it will not irritate lungs when applied normally.
Potential Side Effects/Adverse Reactions
Responses to topical Bis-(C24-30 Alkyl/Butyl) Dimethicone differ from person to person. The issues below are possible yet unlikely for most users when the ingredient is properly formulated.
- Mild skin irritation – rare itching or redness can occur in individuals with silicone sensitivities
- Clogged pores or breakouts – heavier feel may trap sebum in very oily or acne-prone skin
- Folliculitis – occlusive films can occasionally inflame hair follicles on the body
- Contact dermatitis – extremely uncommon allergic reaction leading to rash or swelling
- Product buildup – repeated use without thorough cleansing may leave a residue that dulls skin or hair
If any adverse reaction appears stop using the product and seek advice from a healthcare professional.
Comedogenic Rating
Rating: 1 out of 5
Bis-(C24-30 Alkyl/Butyl) Dimethicone has a very low chance of blocking pores because its large silicone structure forms a breathable layer that sits on top of the skin. The added alkyl and butyl chains boost slip and staying power yet remain chemically inert, so buildup is unlikely when the skin is cleansed regularly.
Most acne-prone users can apply products containing this ingredient without triggering extra breakouts, though those with extremely oily skin might still prefer lighter formulas.
Keep in mind that overall pore clogging potential depends on the full recipe. A cream packed with heavy waxes could feel more occlusive even if this silicone alone is mild.
Summary
Bis-(C24-30 Alkyl/Butyl) Dimethicone is a cushioning emollient that smooths, softens and locks in moisture by filling surface gaps and forming a flexible protective film. Its blend of fatty chains and silicone backbone delivers a luxe feel without stickiness.
The ingredient appears in select high end moisturizers, primers and lip treatments but is less common than standard dimethicone because it costs more and lends a richer texture suited to targeted products.
Safety studies show it is non sensitizing and stable for daily topical use. Still, trying a patch test with any new product is a sensible step to make sure your skin agrees with the full formula.