Keratin treatment has become a staple in modern hair care, promising smoother, shinier, and more manageable locks. At its core, this treatment is a chemical process that reshapes the structure of the hair to reduce frizz and curl. Understanding how keratin treatment works requires a look at the science behind the formula and how it interacts with the hair shaft on a molecular level.
The Science Behind the Smoothness
The primary active ingredient in most professional keratin treatments is a modified form of keratin, a protein that is already the building block of hair, skin, and nails. When applied to damp hair, this solution is worked into the strands using a flat iron. The heat serves a dual purpose: it dries the hair and acts as a catalyst for the chemical reaction. The heat opens the hair cuticle, allowing the keratin proteins to penetrate deep into the cortex. As the formula bonds with the hair's natural keratin, it effectively fills in the gaps and weak spots that cause frizz and roughness.
Neutralizing the Bonds
For the smoothing effect to set, the hair must undergo a neutralizing phase. After the application and initial drying, a clarifying rinse is performed to remove any remaining residue. The critical step occurs when a flat iron is used again at a high temperature to seal the formula. This heat triggers the cross-linking of the keratin proteins, creating a rigid, protective layer around the hair shaft. During this stage, the disulfide bonds within the hair are broken and then reformed in a straight alignment, locking the hair into a smoother configuration that can last for several months.
The Role of Formaldehyde
One of the most debated aspects of keratin treatments is the use of formaldehyde or formaldehyde-releasing agents. In the classic Brazilian blowout and similar treatments, formaldehyde is released as a gas during the sealing process to create a strong, durable bond. This gas helps the keratin to lock onto the hair structure permanently. However, because this gas can be irritating to the eyes and respiratory system, many manufacturers have developed "formaldehyde-free" alternatives. These alternatives use amino acids or other chemicals to achieve similar bonding results without the harsh fumes, though some argue that the longevity of the treatment may differ.
What to Expect During a Session
A standard keratin treatment session is not a quick trip to the salon; it is a time-intensive process that often requires three hours or more. The stylist will begin by washing the hair with a clarifying shampoo to strip away oils and product buildup. The keratin solution is then applied section by section, ensuring full saturation from root to tip. The hair is dried and flat ironed in small sections, a meticulous process that ensures the heat penetrates the keratin deeply. The final rinse removes the bulk of the residue, leaving behind only the bonded protein.
Maintenance and Aftercare
The longevity of the treatment heavily depends on the client's maintenance habits. To preserve the smoothness, it is recommended to avoid sulfates and sodium chloride in shampoos, as these ingredients can strip the keratin bond. Clients are often advised to use sulfate-free and keratin-specific hair care products. Additionally, swimming in chlorinated or saltwater pools can break down the treatment faster, so tying hair up or wearing a swim cap is essential. Touch-up appointments are usually required every few months to address new growth and maintain the integrity of the style.
