2. Hair Dye Statistics:
It is estimated that more than one-third of women over age 18
and about 10 percent of men over age 40 use some type of hair
dye
THIS ONE I NEED TO FIND INFO
3. Hair Dye
PERMANENT
SEMIPERMANE
NT
TEMPORARY
This is mixed with developer
and remains in the hair shaft
until new growth of hair occurs.
It's used to match, lighten, and
cover gray hair. Permanent hair
color generally contains
ammonia, oxidative tints, and
peroxide.
???????
Hair dyes that changes the
hair colour temporarily for
a certain period of time
and can be removed after
used.
Available in various forms
including
rinses, shampoos, gels, sp
rays, and foams.
Typically brighter and
more vibrant than semi-
permanent and
permanent hair color.
5. PERMANENT HAIR DYE
What chemical processes have my ~100000 strands of hair gone
through?
Hair dyeing by oxidation came from the observation
that colourless p-phenylenediamine produces a
coloured compound when subjected to
oxidation. More scientifically put, permanent hair
colouring involves the in-fibre formation of indo-
dyes from colourless precursors by oxidation with
hydrogen peroxide, under alkaline conditions. The
primary intermediates are p-phenylenediamines
or p-aminophenols which are easily oxidised by
hydrogen peroxide to form p-benzoquinone imines. 3
I NEED TO EDIT A BIT
6. PERMANENT HAIR DYE
primary intermediates couplers
aromatic para
compounds, such as
1,4-diaminobenzene
or 4-aminophenol.
The couplers are
meta-substituted
derivatives of aniline.
They come in three
major classes based
on the color that
they produce when
they react with the
primary
intermediate.
chemical compounds
that define the color
of the hair dye.
Shown here are
three red couplers
(A,B,C), two yellow-
green couplers (D,E)
and a blue coupler
(F).
7. The mechanism of oxidation dyes involves three steps:
(1) oxidation of p-phenylenediamine (or similar stuctures, below) to the quinonediimine
derivative
(2) involves the attack of this quinonediimine on the coupler (with chosen colour properties) by
electrophilic aromatic substitution.
(3) the product from the quinonediimine-coupler reaction oxidises to the final hair dye.
OXIDATION IN HAIR DYES: The use of hydrogen peroxide to develop the colour also
allows for bleaching of the natural pigment by one or two shades at the same time as the
synthetic colour is being formed.
8. Caution!
secondary amines, which are either found in all permanent hair
dyes or are formed in them, can penetrate the skin and stay on
the hair for weeks, months or even years after the dye is
applied.
Adverse effects include
o Temporary skin irritation and allergies
o Hair breakage
o Skin discoloration
o And unexpected hair color results
9. Bleaching
• For bleach to change the color of hair it has to be
able to penetrate below the cuticle surface
o Usually done by mixing bleach component with a
alkaline solution (often ammonia)
o This alkali (pH of 8 or 9)swells the hair fiber
causing cuticles to separate and open, allowing
bleach to penetrate the cortex
10. Bleaching
• Bleaching is very damaging to hair as well as emitting
a sulfuric odor
o Hydrogen peroxide breaks the sulfur bonds which
releases larger amounts of sulfur
o This causes hardening, loss of mass, and produces
smell
minimized by using low levels of peroxide in
cosmetic bleach
12. Temporary Hair dye
Consists of:
•water
•organic solvents
•gums
•Surfactants
•conditioning agents.
Usually does not contain as much harmful chemicals compared to
permanent hair dyes.
CIK ZUZU THIS ONE NEED MORE INFO.
MECHANISM? FORMULA? ETC.
13. Differences Between Permanent &
Temporary Hair dyes
Temporary Hair Dyes Permanent Hair Dyes
safer to use as the chemicals can be
washed of
may cause permanent damaged to
users as the chemicals are harmful
form a layer on hair shaft and do not
penetrate it. So they usually wash out
the next time you shampoo
fully penetrates the hair shaft & use
chemicals that strip the hair of its
natural color and replace it with
another color—a permanent dye.
Can be washed off immediately Cannot be wash off
14. Potentially Dangerous Chemicals in Hair Colouring Products
Chemicals in hair colouring products include:
•PPD(para-phenylenediamine)which can cause allergic reactions such as
burning and headaches and is also a potential carcinogen;
•coal tar, which is in 70 percent of hair colouring products and can cause
allergic reactions;
•lead acetate, which has been banned in European countries as a possible
carcinogen and, as with, other lead products, may cause potentially
serious neurological problems;
•DMDM hydantoin, a preservative that has been linked to immune system
problems;
•ammonia, which can be toxic and corrosive and may cause respiratory
problems;
•resorcinol, which can be an irritant and is a potential carcinogen.
Caution!
15. Effects of hair dyes:
Temporary skin irritation and allergy
Hair breakage
Skin discoloration and unexpected hair color results
Loss of hair and in extreme cases BALDING
It can also caused constipation and other dangerous disruptions
within human organs if inhaled or digested by body.
I NEED TO EDIT A BIT
16. HI BELOVED FRIENDS
THANK YOU FOR GIVING
ME ON TIME AND SORRY
IF I’M DEMANDING TOO
MUCH OK HERE TAKE
MY FLYING KISS
MUACKS XOXOXOX
Permanent hair color generally contains ammonia, oxidative tints, and peroxide. All permanent haircolor products and lighteners contain both a developer, or oxidizing agent, and an alkalizing ingredient as part of their ammonia or an ammonia substitute. The purpose of this is to1)raise the cuticle of the hair fiber so the tint can penetrate,2)facilitate the formation of tints within the hair fiber,3)bring about the lightening action of peroxide.
This is achieved by mixing the peroxide bleach with an alkaline solution, most commonly ammonia-I need to memorise thisBefore the bleach can change the colour of the hair, must penetrate below the surface of the hair’s cuticle. –l need to memorise this
Currently there is not an organic permanent hair dye that is made entirely without the following, even tho researchers are trying to make the ones that does not contain these chemicals