What Is Quaternium-90?
Quaternium-90 is the cosmetic name for di(palm-oil-alkyl)dimethylammonium chloride, a quaternary ammonium compound made from palm-derived fatty alcohols and a nitrogen-containing base. Chemists convert palm oil into long-chain fatty alcohols, attach a dimethylamine group, then complete the process with a quaternizing step that locks in a permanent positive charge. This charge is the reason Quaternium-90 clings to negatively charged surfaces like hair fibers.
Quaternary ammonium ingredients have been used since the 1950s to tame flyaways in hair care. Quaternium-90 is a newer variation created to be more plant-based and less greasy, so formulators began adding it to modern rinse-off and leave-in products in the early 2000s. Today you will spot it in shampoos, conditioners, detangling sprays, hair masks, anti-frizz creams, styling mousses and even some pressed face powders where static control helps the powder sit smoothly.
Quaternium-90’s Cosmetic Benefits/Uses
The main value of Quaternium-90 comes from its antistatic action, which delivers several practical payoffs in beauty products.
As an antistatic agent it neutralizes the electric charge that builds up on hair or dry powder particles. In hair care this means fewer flyaways, easier combing and a sleeker finish that lasts throughout the day even in low-humidity conditions. In pressed or loose powders it helps the formula release evenly from the pan or puff so application looks smooth rather than patchy.
Who Can Use Quaternium-90
Quaternium-90 is considered gentle enough for most skin and hair types. Its lightweight conditioning film suits fine or oily hair without weighing it down while still giving dry or frizz-prone strands extra smoothness. Because it is not known to clog pores it is generally acceptable for acne-prone or sensitive skin, though anyone with a history of reactions to quaternary ammonium compounds should stay alert for irritation.
The ingredient is synthesized from palm-derived fatty alcohols, so it is plant based and free of animal by-products, making it compatible with vegan and vegetarian lifestyles. Ethical buyers may still want to confirm that the finished product is cruelty free and that the palm source is sustainably certified.
Current safety assessments show no evidence that topical Quaternium-90 poses a risk to pregnant or breastfeeding women when used as directed, but this is not medical advice. Expectant or nursing mothers should review any personal care product with their physician to be sure it fits their individual needs.
Quaternium-90 does not increase photosensitivity, so it will not make skin or hair more prone to sun damage. It is also color-safe for dyed hair and compatible with most common cosmetic ingredients.
Potential Side Effects/Adverse Reactions
Reactions to Quaternium-90 vary from person to person. The points below outline possible, but uncommon, effects when the ingredient is used topically in properly formulated products.
- Mild skin or scalp irritation
- Allergic contact dermatitis in individuals sensitized to quaternary ammonium compounds
- Eye irritation if the product accidentally gets into the eyes
- Product build-up that can leave hair feeling coated when heavy formulas are used excessively
If any unwanted reaction occurs stop using the product and consult a healthcare professional or dermatologist.
Comedogenic Rating
Rating: 1 / 5. Quaternium-90 is classed as a low-residue quaternary ammonium salt that rinses away easily with water, so it does not stay on the skin long enough to block pores. Its molecules are positively charged and water compatible, which keeps them from blending into skin sebum the way richer oils or waxes can. For this reason it is generally suitable for people who are prone to acne or breakouts.
The only time pore clogging could become a concern is if the ingredient is combined with heavy butters or occlusive silicones in the same formula, in which case the overall product could feel build-up-prone on very oily skin.
Summary
Quaternium-90’s key job is antistatic control. Its permanent positive charge attracts it to negatively charged surfaces like hair cuticles and powder particles, cancelling out static electricity so hair sits flatter, styles hold longer and face powders apply without patchy lift-off. It also lends a light conditioning feel that smooths strands without greasiness.
While not as common as classic conditioning agents such as Behentrimonium Chloride, Quaternium-90 has carved a steady niche in modern clean-leaning hair care lines that want plant-based options and a lighter touch.
Current safety data shows it is low risk for topical use with only rare reports of irritation. As with any new cosmetic ingredient it is wise to patch test a fresh product before full use to make sure it suits your individual skin or scalp.