Hair Colouring Theory and Application Flashcards

What are the three primary colours in hair colour theory?

Answer: Red, blue, yellow

The three primary colours are red, blue, and yellow. They cannot be created by mixing other colours and are the foundation of all colour theory used in hair colouring.

What is the purpose of a developer (hydrogen peroxide) in permanent hair colour?

Answer: To open the cuticle and activate the oxidation process that develops colour

Developer (hydrogen peroxide) serves two purposes: it opens the cuticle to allow colour penetration into the cortex, and it activates the oxidation process that develops the colour molecules and lightens natural melanin.

What volume of developer is most commonly used for standard grey coverage with permanent colour?

Answer: 20 volume (6%)

20 volume (6%) developer is the standard choice for permanent colour applications providing grey coverage. It lifts natural colour by approximately 1-2 levels and provides sufficient opening of the cuticle for deposit.

What does the 'level' system in hair colour refer to?

Answer: The degree of lightness or darkness of a colour

The level system measures the degree of lightness or darkness of a hair colour on a scale from 1 (black, darkest) to 10 (lightest blonde). It is independent of the tone or hue of the colour.

What are contributing pigments (also called undertones)?

Answer: The natural warm pigments revealed when hair is lightened

Contributing pigments are the natural underlying warm pigments (eumelanin and pheomelanin) that are exposed when natural hair colour is lightened. They progress from red (at darker levels) through orange to yellow (at lighter levels).

What is a patch test and when should it be performed?

Answer: A skin allergy test done 24-48 hours before a colour service to check for adverse reactions

A patch test (predisposition test) is a small application of colour mixture applied to the skin, usually behind the ear or inner elbow, 24-48 hours before service. It identifies potential allergic reactions to colour ingredients, particularly PPD.