Haircoloring and Lightening
Haircolor questions test color theory, level, developer choice, gray coverage, and lightening safety. You need to predict the result from the level and tone you select, then apply it without overlapping or overprocessing.
Color theory and levels
- Levels run from 1 black to 10 lightest blonde; tone can be warm, cool, or neutral.
- Primary colors mix to secondary colors, and complementary colors neutralize unwanted tone.
- Developers commonly work as 10 volume for deposit, 20 volume for about one level of lift, 30 volume for two to three levels, and 40 volume for three to four levels, but always follow the manufacturer.
Safety and application
- Patch-test 24 to 48 hours before color, and strand-test when the formula or hair history is uncertain.
- Section the hair, apply evenly, and control processing time; overlapping lightener or color can damage hair and create bands.
- For gray, use an opaque formula at the desired level; resistant gray may need a base or a longer processing time.
- Lightener lifts pigment; toner adjusts the final tone. Watch the scalp and do not use 40 volume on scalp unless the product allows it.
Worked example
A client at level 5 brown wants level 7 warm brown. A level 7 color with 30 volume can lift about two levels and deposit warmth; strand-test for brass. If the hair is resistant, pre-lighten and tone rather than putting 40 volume on the scalp.
Traps that cost marks
Using the wrong developer volume, skipping the patch test, overlapping bleach, using 40 volume on the scalp, choosing the wrong toner, and leaving color on too long.