Page 41 - HAIR COLOUR

Do not carry out a skin test for a bleach and toner. Bleach contained
under a plaster on sensitive skin for 48 hours will always give a reaction,
due to the fact that the bleach will just burn the skin. If the bleach is
mixed to strong, say with 40 volume peroxide, or left on the scalp to long,
red swelling around the hairline may occur leaving the scalp slightly sore,
but is otherwise unaffected and will return to normal after 24 hours.

Bleach toners are usually just toners with out a base shade, and do not
contain the PPD’S you usually find in dark colours, so there is no need
for a skin test.

A strand test however, is a good idea. A lot can be learnt from a strand
test, such as whether the hair is strong enough to stand bleaching without
breaking, drying or over processing. It always good to know the
percentages of yellow pigments in the hair before you begin, so as you
can mix the appropriate bleach mixture to achieve the target colour.

To carry out a strand test expose an area of hair behind the ear holding
the rest of the hair away with clips. Select a shallow, but wide section as
you would for a streak, place inside a Visi-Color packet and apply bleach
to the hair just beneath the adhesive strip, do not apply bleach to the root
area, because this area has not been keratinised and will lift very quickly
misleading you as to how long it will take to lift the whole length of the
hair to the desired colour.

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