Polyurethane-18

What is Polyurethane-18?

Polyurethane-18 is a synthetic copolymer from the polyurethane class, formed by reacting polyols with diisocyanates to create a high-molecular-weight resin. Primarily featured in hair care products like sprays, gels, mousses, and styling aids, it excels as a film-former. Upon application, it coats the hair shaft with a sheer, elastic film that captures style, combats environmental factors like moisture, and preserves shape without brittleness. Its binding nature also strengthens solid or pressed formats, such as powders and bars, by promoting ingredient adhesion for better structural stability and user-friendly application. This dual functionality supports versatile use across styling needs, balancing hold with natural movement.

Comedogenic Rating 0/5 Low risk of clogging pores
EWG Safety Rating 3 View on EWG →

Roles in Formulation

This ingredient serves the following purposes in cosmetic formulations:

Binding
Provides cohesion by helping ingredients stick together, improving the strength and integrity of pressed powders, tablets, or solid bars.
Hair fixing
Improves style retention by depositing film-forming polymers that hold hair in place while balancing stiffness, flexibility, and humidity resistance.
Hair fixative
Provides style hold by forming a film on hair, helping maintain shape, reduce frizz, and improve durability in sprays, gels, and mousses.

Benefits

Delivers flexible, long-wear hold in hair products for style maintenance.

Boosts resistance to humidity and frizz for enduring results.

Strengthens cohesion in solid cosmetics like powders for improved durability.

Who It's For

A quick guide for who this ingredient may suit (and who should be cautious).

Who May Benefit Who Should Avoid
People styling fine or straight hair for added structure.
Those with rare sensitivities to synthetic polymers.
Individuals in humid environments seeking reliable hold.
People preferring fully natural or plant-based formulations.
Users of pressed powders or bars wanting enhanced integrity.
Individuals experiencing scalp discomfort from styling residues.

Safety Notes

  • Deemed safe for use in cosmetics at typical levels by expert reviews.
  • Presents low risk of comedogenicity or pore-clogging.

Frequently Asked Questions about Polyurethane-18

What products contain Polyurethane-18?

Commonly found in hair sprays, gels, mousses, and some pressed powders or solid cosmetics.

Is Polyurethane-18 suitable for daily hair styling?

Yes, its flexible film supports everyday use while maintaining style and movement.

Does it affect hair health?

It provides temporary hold without inherent damage, rinsing off with regular cleansing.