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New [Keratin Alpha Sleek] Professional hair mask for long-lasting smoothness, frizz & volume control.
Description
Keratin Alpha Sleek professional hair mask by L'Oréal Professionnel, formulated with Keratin-alpha shaper and Amino-acid chains. For long-lasting smoothness, frizz & volume control.
This professional mask has a rich, sensorial texture that deeply nourishes, hydrates and conditions whilst reshaping and smoothing hair keratin. It provides up to 3x less unwanted volume1, helps protect the hair from breakage and improves softness from the first use2.
1Instrumental test. 2Instrumental test after 1 application of shampoo, mask & serum.
Results & Benefits
- Reprogram hair for up to 2 weeks of frizz control1.
- Up to 5x smoother hair and 2x less frizz2.
- Controls unwanted volume for daily styling in half the time2.
- Adds softness and instant shine that lasts up to 5 days3.
1Consumer test on 68 participants, 1 application/week for 4 weeks. Based on 15-day break observation. 2Instrumental tests with 4 uses of the Shampoo + Smooth Transformer + Serum routine. 3Instrumental test after 1 application of shampoo, mask & serum.
Instruction of use
Leave on for 5 minutes and rinse. In case of contact with eyes, rinse immediately and thoroughly.
Ingredients
AQUA / WATER / EAU • CETEARYL ALCOHOL • BEHENTRIMONIUM CHLORIDE • CITRIC ACID • CETYL ESTERS • GLYCERIN • GLYCINE • ISOPROPYL ALCOHOL • AMINOPROPYL DIMETHICONE • POTASSIUM HYDROXIDE • ISODODECANE • PHENOXYETHANOL • BIS(C13-15 ALKOXY) PG-AMODIMETHICONE • BUTYROSPERMUM PARKII BUTTER / SHEA BUTTER • STEARETH-100 • PROPYLENE GLYCOL • HYDROXYPROPYL GUAR • PEG-150/DECYL ALCOHOL/SMDI COPOLYMER • TETRAMETHYL ACETYLOCTAHYDRONAPHTHALENES • POLYQUATERNIUM-37 • LINALYL ACETATE • PROPYLENE GLYCOL DICAPRYLATE/DICAPRATE • CHLORHEXIDINE DIGLUCONATE • CARVONE • CITRUS LIMON PEEL OIL • LIMONENE • COUMARIN • LINALOOL • CITRUS AURANTIUM BERGAMIA PEEL OIL • BUTYLENE GLYCOL • PPG-1 TRIDECETH-6 • PINENE • ACRYLATES/STEARYL METHACRYLATE COPOLYMER • SORBITAN OLEATE • CARBOMER • SODIUM LACTATE • TAURINE • POLYSORBATE 20 • EDTA • PALMITOYL TRIPEPTIDE-1 • PALMITOYL TETRAPEPTIDE-7 • PARFUM / FRAGRANCE
This ingredients list is subject to change and depends on country location selling. Consumers should refer to the product packaging for the most relevant ingredients list. In case of problem, please contact the consumer care center.
Your questions and our answers on Keratin Alpha Sleek range.
What is Keratin Alpha?
It is the primary protein that forms the very core structure of your hair, residing at the deepest level of the fiber. It is the building block that dictates each strand’s shape, strength, and elasticity.
Why does Keratin Alpha determine hair outer shape?
Alpha-keratin is the fundamental structural protein that forms the hair. Its internal helical arrangement, along with the extensive network of bonds within the hair's cortex, dictates the strand's overall geometry, and ultimately determines if hair appears straight, wavy, or curly.
What hair needs does this range address?
The Keratin Alpha Sleek range has been formulated with stylists for all those who want to reduce frizz, improve smoothness, and keep hair straighter and softer, with results that last. In fact, whilst other at-home smoothing treatments only act on the surface of the hair for temporary results, KAS transforms hair at the Keratin Alpha level, for up to 2 weeks of frizz & volume control, ensuring daily styling in half the time1. It is suitable for all hair types.
1Instrumental tests with routine 4 times of Shampoo, Smooth Transformer and Serum.
Does Keratin Alpha Sleek range contain keratin?
Keratin is an animal-derived ingredient, also found in human hair. These products don’t contain keratin, but reprogram hair from deep inside the fiber at Keratin Alpha level, reshaping Keratin Alpha chains for up to 2 weeks of smooth, frizz-controlled hair1.
1Consumer test on 68 participants, 1 application/week for 4 weeks

















