Final answer:
The color left in the hair after decolorizing is known as its base color. Decolorizing removes natural pigments, paving the way for a new hair color through dye application.
Step-by-step explanation:
After the hair goes through the decolorizing process, the color that is left in the hair is known as its base color. Decolorizing stages involve the chemical removal of natural pigments from the hair, potentially leading up to ten stages depending on the desired level of lightness. This process alters the hair's original color and exposes the underlying pigments or the base color, which can then be tinted or toned to achieve a new hue.
Hair coloring techniques vary between permanent and semi-permanent options, with permanent changes involving a reaction that includes a developer and dye molecules that create a new color. Semi-permanent color, on the other hand, washes out over time and is less harsh than permanent dye, but may not completely cover gray or white hair. Understanding the base color is essential for professional or at-home coloring to achieve the desired final hair color.