Unlike
some of the permanent hair dyes, temporary
hair colors carry very little risk
of irritant or allergic dermatitis when
they are used.
Natural colorings
Natural colors have been used on hair
since ancient times. Most of them are
made from plants. Henna is by far the
best known. It is widely used to this
day to redden hair, especially dark
hair, and the color produced lasts
through several shampoos. But its concentration
is difficult to control, and hence results
can be unpredictable. It has been reported
to cause
asthma and allergies in some people,
and people who suffer from these ailments
should be wary of using it. Henna
should not be used on gray hair, as
it turns it orange!
Semi-permanent dyes
Special hair dye preparations are made
for coloring gray hair. They can be
used to add highlights too. They do
not contain a single dye but mixtures
of red, yellow, blue, and orange dyes
in various proportions. The dyes have
small molecules, which means they can
pass through the cuticle into the cortex
easily, and
This
lady has colored her hair for many
years:
careful treatment and her technician's
expert skill
have concealed the premature graying
she disliked |
|
Here
color has been used to fresh and
dramatic effect
without damaging the scales of the
cuticle. Since they can enter the
hair shaft easily, they can also be
washed out relatively
easily.
The
result of inexpert hair coloring
|
