What Is Nylon-11?
Nylon-11 is a synthetic polymer made from 11-aminoundecanoic acid, a building block derived mainly from castor oil. The material belongs to the nylon family of plastics yet it stands out for its light weight, smooth feel and excellent film-forming ability. First developed in the 1940s for industrial uses, it attracted attention from beauty formulators several decades later when they noticed its ability to improve texture and wear in makeup powders. Today the cosmetic grade of Nylon-11 is produced through polymerization, a controlled heat process that links many molecules of 11-aminoundecanoic acid into long, uniform chains. The finished powder is then milled to specific particle sizes suited for personal care products.
You will most often find Nylon-11 in pressed and loose powders, foundations, primers, lipsticks, mascaras, skin-smoothing creams and certain sunscreen or anti-aging formulas where a silky feel and good spreadability are desired.
Nylon-11’s Cosmetic Benefits/Uses
In formulas, Nylon-11 serves two main technical roles that translate into a better look and feel for the user
- Bulking – Adds volume without significant weight letting manufacturers create powders that press well and appear fuller in the compact. This also helps dilute pigments evenly so color payoff is smooth and buildable
- Viscosity Controlling – Adjusts the thickness of creams, gels and liquid makeup ensuring the product is neither too runny nor too stiff. A balanced viscosity leads to easier application and a more even finish on the skin
Who Can Use Nylon-11
Nylon-11 is generally well tolerated across most skin types, including oily, dry, combination and normal skin. Its particles are lightweight and non occlusive so they do not trap excessive oil or moisture. Extremely reactive or allergy-prone skin could still experience sensitivity, though this is uncommon because the polymer is considered inert.
The raw material is produced from 11-aminoundecanoic acid sourced largely from castor oil, a plant crop, so it is suitable for vegans and vegetarians. As always, check finished product certifications if a fully vegan supply chain and cruelty-free status are priorities.
Current safety data indicate no known risks for women who are pregnant or breastfeeding when Nylon-11 is used topically. Because every pregnancy is unique this is not medical advice, and anyone who is expecting or nursing should review their entire skincare routine with a medical professional.
Nylon-11 does not cause photosensitivity, meaning it will not make skin more prone to sunburn. It also plays well with common actives such as vitamin C, retinoids and chemical or mineral sunscreens.
Potential Side Effects/Adverse Reactions
Responses to any cosmetic ingredient can vary from person to person. The points below cover potential side effects of topical Nylon-11 use, but these outcomes are rare when the ingredient is properly formulated and most users will not encounter them.
- Contact irritation – mild redness or itching in individuals with highly sensitive skin
- Allergic reaction – very uncommon sensitization to the polymer itself or trace residual monomer
- Acne flare ups – possible if Nylon-11 is combined with heavy oils in a formula and used on skin that is already breakout prone
- Eye discomfort – watering or stinging if loose powder accidentally gets into the eyes
If you experience any of these issues stop use immediately and seek guidance from a healthcare professional or dermatologist.
Comedogenic Rating
Nylon-11 receives a comedogenic rating of 1 out of 5. Its particles are non greasy, do not swell with oil and sit on the surface without blocking pores. The low but non-zero rating accounts for the fact that it is still a solid powder that can mix with heavier emollients in certain formulas which might mildly increase the chance of clogged pores for some users.
Because of this low score Nylon-11 is generally suitable for acne or breakout prone skin, especially when it is part of lightweight or oil free products.
Formulation matters; pairing Nylon-11 with highly occlusive waxes or butters can raise the overall comedogenic potential of the finished product even though the polymer itself remains low risk.
Summary
Nylon-11 acts mainly as a bulking and viscosity controlling agent. Its fine spherical particles build volume in powders so colors look smooth and even while its ability to fine-tune thickness gives creams and liquids a pleasant glide and balanced consistency.
It is a niche yet growing ingredient popular in long-wear makeup and silky skin care where a soft focus feel is desired but still less common than talc or silica so you may not see it in every product on the shelf.
Current data shows Nylon-11 is considered safe for topical use with a very low incidence of irritation or allergy. As with any new cosmetic we recommend performing a small patch test before full application to make sure your skin agrees with the formula.