Hairspray — What's Hiding in the INCI List and How to Choose the Right One?

How does hairspray work? The chemistry behind the hold

Hairspray is a product most people use on instinct — you spray it onto your hairstyle and count on hours of hold. Yet behind that simple gesture lies a complex chemistry of polymers, solvents and propellants. Understanding a hairspray's INCI list lets you choose not only a more effective product, but also one that is safer for your hair and the environment.

The basic principle is the formation of a thin, flexible polymer layer on the surface of the hair. Once the solvent (usually alcohol) evaporates, the polymer hardens and “freezes” the style in the desired shape. The higher the polymer concentration and the stiffer the polymer chain, the stronger the hold.

VP/VA Copolymer — the most popular film-former in hairsprays

VP/VA Copolymer (a copolymer of vinylpyrrolidone and vinyl acetate) is the absolute foundation of most hairsprays. Its job is to create a transparent, flexible film on the hair that holds the style in place while still allowing a certain degree of movement.

The ratio of VP to VA in the copolymer determines the final properties. A higher proportion of VP (vinylpyrrolidone) provides better water solubility and easier wash-out, but a weaker hold. A higher proportion of VA (vinyl acetate) increases humidity resistance and hold strength, at the cost of being harder to remove. Manufacturers tune these proportions according to the declared hold level — from flexible “flexible hold” to extreme “mega hold.”

On the INCI list, look for this ingredient near the top — the higher it appears, the more polymer there is in the formula, and therefore the stronger the hold. If you want to check the full profile of this ingredient, visit our ingredient database.

Octylacrylamide/Acrylates Copolymer — support for humidity resistance

This acrylic copolymer appears in hairsprays as a second film-former, complementing the action of VP/VA. Its key advantage is high hydrophobicity — it forms a barrier that protects the style against moisture more effectively than VP/VA Copolymer alone.

Octylacrylamide/Acrylates Copolymer is especially valued in hairsprays designed for use in challenging weather — rain, fog, high air humidity. Premium manufacturers often combine both polymers to achieve synergy: VP/VA delivers film flexibility, while Octylacrylamide provides water resistance.

Alcohol denat. — the solvent that ensures lightning-fast drying

Alcohol denat. (denatured alcohol, denatured ethanol) is the most common ingredient in hairsprays — it usually sits in first or second place on the INCI list. Its role is twofold: it dissolves the film-forming polymers and at the same time ensures ultra-fast evaporation after application.

Why alcohol specifically? Because it evaporates far faster than water, allowing instant hold without leaving hair wet or clumped together. The alternative would be water-based hairsprays, but these dry more slowly and deliver a weaker hold — which is why they are rare on the market.

It is worth knowing that alcohol denat. has a drying effect on hair with intensive, daily use. If you use hairspray several times a week, consider products with added panthenol or glycerin, which partly offset the drying effect.

Hold levels — from flexible to strong hold

Hairspray manufacturers use hold scales (most often 1–5, or descriptive ones: light, medium, strong, mega), but there is no industry standard. This means one brand's “medium hold” may correspond to another's “strong hold.”

From an INCI perspective, hold strength is determined by:

• Polymer concentration — the higher up the INCI list, the stronger the hold
• Polymer type — stiff polymers (e.g. Polyurethane-14) give a harder hold than flexible ones (VP/VA)
• VP-to-VA ratio — more VA = stronger hold
• Presence of resins — Shellac in premium hairsprays delivers an extremely durable hold

If you are looking for a specific product with a particular hold level, use our product search to compare formulas.

Aerosol propellants — butane, isobutane and propane in your hairspray

Aerosol hairsprays contain a blend of propellant gases: butane, isobutane and propane. The same gases that power cigarette lighters are responsible for dispersing the hairspray as a fine mist. On the INCI list you will find them as Butane, Isobutane and Propane.

Propellants can make up as much as 40–60% of an aerosol product's mass. They are not active ingredients — their only job is to push the formula out of the can and atomize it into fine droplets. Once applied to the hair, they evaporate immediately.

An alternative to aerosols are hairsprays with an atomizer (pump), which contain no gaseous propellants. They produce slightly larger droplets and less even coverage, but eliminate the problem of VOCs from propellants.

VOCs — volatile organic compounds and their impact on health

VOCs (Volatile Organic Compounds) are volatile organic compounds emitted by both the alcohol and the propellants in hairsprays. In enclosed spaces they can reach concentrations that irritate the airways, especially in people with asthma or allergies.

VOC regulations for cosmetics vary by region. The European Union limits VOC content in cosmetic aerosols, but the limits are relatively liberal compared with California's regulations (CARB), which force formulas with reduced VOC content.

Practical tips to minimize VOC exposure:

• Use hairspray in a well-ventilated room
• Hold the can at least 30 cm from your head
• Consider hairsprays with an atomizer (free of gaseous propellants)
• Check products in our category catalog to find options with lower VOC emissions

What to look for when choosing a hairspray?

Choosing the right hairspray comes down to matching it to your hair type, the desired effect and how often you use it. Fine hair responds better to hairsprays with a light hold and low polymer concentration — strong formulas weigh it down and clump it together. Thick, heavy hair needs stronger polymers and a higher concentration of VP/VA.

If easy wash-out matters to you, look for hairsprays where VP dominates over VA — they will be more water-soluble. If rain resistance is the priority, opt for a formula with Octylacrylamide/Acrylates Copolymer.