What is oxidation particularly related to haircoloring.

Hello brockaf,

Thank you for your question about oxidation. To the first part of your
question
oxidation is a chemical reaction in which atoms lose electrons. There
is quite a good definition online from "A Dictionary of Science,
Oxford University Press, © Market House Books Ltd 1999"  at

http://www.xrefer.com/entry.jsp?xrefid=490915&secid=.-

 In relation to hair coloring you are probably thinking of the common
hair treatment called "Peroxiding". In this case a chemical called 
hydrogen peroxide (H2O2) is used. It should be noted that this
chemical is quite strong and should be kept away from eyes. When hair
is treated with hydrogen peroxide it is usually a weak solution.

For more information about hydrogen peroxide from "A Dictionary of
Science, Oxford University Press, © Market House Books Ltd 1999" see
it online at

http://www.xrefer.com/entry/489055

But how does this change the colour of your hair? Most chemicals have
electrons in them that generally allow certain colours of light to
reflect. If you have red hair for example most light being reflected
is red. If you add an oxidising agent like hydrogen peroxide this
'takes away' some of the electrons of the red colour(melanin) in the
hair and changes the way white light is reflected. This results in
more colours being reflected, which generally means it gets whiter.

The university of Hawaii has a page that describes some of this with a
diagram at

http://naio.kcc.hawaii.edu/chemistry/everyday_bleach.html


The process of peroxiding hair is further described at pbs.com as...

"The color of your hair comes from a natural pigmentation called
melanin. It
lives inside the hair shafts. When hydrogen peroxide - which permanent
dyes are made with - makes contact with your hair, it softens the
melanin inside, breaking it down into a colorless liquid that drips
out of your hair. In other words, it "strips" (or melts away) all the
color in your hair. Another chemical in the hair dye then paints a new
color onto the "blank"(yellow white) hair ...  "

http://www.pbs.org/newshour/infocus/fashion/hair.html


You may find some useful information from the cosmetic company
L'oreal, as they research hair quite alot at
 
http://www.loreal.com/loreal-hair-science/us/home.asp


search strategy:

http://www.xrefer.com  oxidation

on google:

hair color melanin


Well I hope this goes some way to answering your question about
oxidation and hair coloring.

kind regards

Oxidation dyeing is the most common way to color hair. The 'dyes' that
are used are not really dyes at all, but dye intermediates that
undergo oxidative coupling reactions in the presence of hydrogen
peroxide to form color in the hair. The dye intermediates diffuse into
the hair and couple to form larger colored molecules, which are locked
into the hair so the dyeing is more or less permanent. Oxidation dye
products are characterized by having two components, a dye bottle (or
tube) and a peroxide bottle. The two are mixed just before using the
product.