Full Article

Chemistry of Hair Coloring

The chemistry of hair coloring is not difficult to understand. Having a working knowledge of the color wheel will make a hair-coloring project go smoothly with great results. A color wheel is a diagram that illustrates how all visible colors originate from the three primary colors of red, yellow, and blue.

The Chemistry of Color

Hair is made up of keratin protein fibers. The process of coloring or dying hair involves an interaction between the keratin fibers and various types of chemical dyeing compounds. Coloring hair consists of carefully guiding this process through the use of bleach or natural hair color enhancing chemicals.

The dyeing procedure can be accomplished through the use of temporary, semi-permanent, and permanent dyes as well as bleaches. These chemicals are worked into the hair structure and either temporarily or permanently alter natural color.

Determine the Underlying Pigment in Natural Hair Color

All naturally occurring hair colors are made up of different percentages of the three primary colors. An equal mixture of all three primary colors will make brown. Natural hair color is determined using a chart of hair swatches of varying levels of darkness. These are numbered from one to ten with one being black and ten being the palest blonde. Each of these hair swatches corresponds to an underlying pigment of red, yellow, oranges, or a combination. Determining the underlying pigment is critical to successful hair coloring. For example, hair darkness of number 7 has an underlying pigment of yellow.

Determine the Color to Neutralize

The next step in a successful hair-coloring project is to determine the primary color to be neutralized. Be it red, blue, or yellow, there is a secondary color exactly opposite on the color wheel that will tone it out. A blonde number 6 will need a blue-based color to neutralize the underlying pigment of orange. Hair this dark may require a toner to be included in the technique to also mask out any remaining brassy tones.

It is important to remember that even if attempting to color hair that has never before been colored, it is not a clean slate. Previously colored hair is a bit more complicated. Not only must the color of the natural re-growth be considered when choosing colors and techniques, considering the processed hair color are essential for success as well. According to the FDA, studies regarding the safety of long-term hair coloring are still ongoing and inconclusive.