Nécessaire Rosemary Leave-In Mask 60 ml — Keratin strengthening treatment, color-safe weekly formula

Nécessaire Rosemary Leave-In Mask is a weekly, leave-in keratin treatment that smooths, softens and strengthens damaged hair while being safe for color-treated strands.

This lightweight 60 ml formula pairs rosemary extract with 5% vegan keratin to deliver immediate slip and longer-term reinforcement of the hair fiber. Designed for both women and men and formulated without sulfates, silicones, parabens, PEGs or phthalates, the mask works as an at-home reconstructive step you leave in—no rinsing required—to reduce breakage and improve manageability over time. The scent blends rosemary with mandarin, jasmine and cedar for a subtle, refined fragrance.

How quickly will I notice smoother hair after using this leave-in mask?

Most users see immediate improvement in surface texture and combability after the first application because the formula adds instant slip and softness. Visible strengthening occurs with repeated weekly use as the vegan keratin helps reinforce weakened strands.

• Instant: reduced tangles and easier brushing right after application.
• Short term (weeks): improved sheen and smoother feel with regular weekly use.
• Long term: reduced breakage from progressive keratin support to the hair shaft.

Can I use this on color-treated or chemically processed hair?

Yes—this mask is safe for color-treated and chemically processed hair because it is formulated without harsh sulfates and silicones that can strip or weigh hair down. It focuses on rebuilding and protecting the fiber while maintaining color integrity.

• Color-safe formulation preserves dye performance between salon visits.
• No sulfates or silicones to accelerate fading or buildup.
• Gentle enough for repeated weekly applications on processed hair.

How do I incorporate the Rosemary Leave-In Mask into my routine?

Apply a small amount to towel-dried or dry hair from mid-lengths to ends once per week, then style as usual—no rinse required. Adjust quantity based on hair length and thickness, using more for coarse or long hair and less for fine textures.

• Step 1: Towel-dry or use on dry hair; distribute evenly.
• Step 2: Focus on damaged zones, avoiding the scalp if you prefer lighter roots.
• Step 3: Leave in and style; repeat weekly or as needed for maintenance.

What are the key ingredients and which benefits do they provide?

The formula centers on rosemary extract for fortifying benefits and 5% vegan keratin to strengthen protein-depleted strands. The product is dermatologist-tested and free from several common additives to reduce irritation risk and avoid buildup.

• Rosemary extract: helps enhance hair resilience and sensory freshness.
• 5% vegan keratin: provides protein support to minimize breakage over time.
• Free-from list: no sulfates, silicones, parabens, PEGs or phthalates for cleaner formulation.

Who this is for: this leave-in mask suits anyone wanting a simple, effective weekly treatment to smooth and strengthen hair—ideal for those with damaged, chemically treated, color-treated or frizz-prone hair, and for anyone seeking a lightweight product that won’t weigh down finer textures. It works for all hair types and textures, for both men and women, and is a convenient at-home step for healthier-looking hair with a subtle herbal fragrance.

Ingredients

Water/Eau/Aqua Propanediol Cetearyl Alcohol Keratin Amino Acids Glyceryl Stearate Rosmarinus Officinalis (Rosemary) Leaf Oil Rosmarinus Officinalis (Rosemary) Leaf Water Rosmarinus Officinalis (Rosemary) Leaf Extract Hydrolyzed Moringa Oleifera Seed Extract Hydrolyzed Jojoba Protein Hydrolyzed Rice Protein Hydrolyzed Pea Protein Hydrolyzed Quinoa Hydrolyzed Vegetable Protein Ceramide AG Ceramide AP Ceramide EOP Ceramide NP Ceramide NG Tocopherol Acetyl Tetrapeptide-3 Biotin Niacinamide