Underlayer color hair, also known as undercoat, refers to the layer of hair that lies beneath the topcoat in animals, providing insulation and protection. In humans, underlayer color hair can refer to the natural hair color that grows beneath visible highlights or dyes.
The underlayer color of hair plays a significant role in determining overall hair color, depth, and tone. Understanding the impact of underlayer color hair can help in choosing the right hair color and achieving desired results. Historically, hair coloring techniques have evolved to enhance or alter underlayer colors, leading to multi-dimensional and sophisticated hair hues.