Hair Colouring Theory and Application Flashcards

What is the effect of applying 40 volume (12%) developer with permanent colour?

Answer: Up to 4 levels of lift with significant lightening

40 volume (12%) developer provides the maximum lift available with permanent colour, lightening up to approximately 4 levels. It is the strongest developer and should be used with caution as it can cause significant damage.

What is the underlying pigment exposed when hair is lightened to level 7 (medium blonde)?

Answer: Orange-yellow

At level 7 (medium blonde), the contributing pigment exposed is orange-yellow. As hair lightens from dark to light, the underlying tones progress from red → red-orange → orange → orange-yellow → yellow → pale yellow.

What is a colour filler and when is it used?

Answer: A product that replaces missing underlying pigments to ensure even colour results when going darker

A colour filler replaces the missing contributing pigments in pre-lightened or colour-treated hair before applying a darker target colour. Without filling, the final colour may appear dull, ashy, muddy, or fade quickly.

What is the term for the first time a client receives an all-over permanent colour application?

Answer: Virgin application

A virgin application is the first permanent colour applied to hair that has never been chemically coloured. The application technique differs from a retouch — colour is typically applied mid-lengths and ends first, then roots.

Why is colour applied to the mid-lengths and ends before the roots during a virgin lightening application?

Answer: Body heat at the scalp accelerates processing, so roots are applied last to ensure even results

During a virgin lightening application, the roots are applied last because body heat from the scalp accelerates the chemical reaction. Applying roots first would result in the roots processing faster and becoming lighter than the lengths.

What is a secondary colour?

Answer: A colour created by mixing two primary colours together

Secondary colours are created by mixing equal parts of two primary colours: red + yellow = orange, red + blue = violet, blue + yellow = green. These are essential in understanding colour wheel relationships for corrective work.