In the world of hair coloring, there are various technologies designed to meet every need. Among them, permanent hair dye remains the most popular choice due to its long-lasting results and its ability to provide full coverage. But how does it actually work, and how does it differ from other types of hair dye?
Permanent hair dye
Permanent hair color works deep within the hair shaft to permanently change the hair’s color. Unlike temporary hair colors, which deposit dyes more on the surface, permanent hair color involves a reaction within the hair itself. Permanent hair color is formulated to open the hair cuticles and allow dyes to penetrate deep into the hair shaft. This reaction, known as oxidation, permanently alters the hair’s pigmentation by creating new colored molecules within the keratin itself. This is why the color does not fade with repeated shampooing: the dyes are truly fixed within the hair.
Permanent Hair Dye vs. Tone-on-Tone Hair Dye: The Key Differences
The main difference lies in the longevity and depth of action:
Tone-on-tone hair color works without penetrating deeply into the hair shaft. The dyes settle on top of the natural color, resulting in a temporary effect. The color gradually fades with each wash, lasting about 6 to 8 weeks. However, this type of hair color does not lighten the hair and only partially covers gray hair.
Permanent hair color works by penetrating deep into the hair shaft to permanently alter the hair’s natural pigmentation. This process relies on opening the cuticle scales, allowing the colorants to bind deeply within the hair cortex. Thanks to this mechanism, permanent hair dye offers long-lasting results, remains intact until the roots grow out, ensures 100% gray coverage, and allows for lightening up to two shades above the natural color.
The Benefits of Permanent Hair Dye
Complete coverage of gray hair
That’s the main advantage of permanent hair dye: it completely covers gray hair, even the most stubborn strands.
Long-lasting wear
The color withstands repeated washing and retains its vibrancy for weeks. Only regrowth at the roots will require a touch-up, usually every 4 to 6 weeks depending on how fast your hair grows.