Oc hair dyes
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Transcript of Oc hair dyes
HAIR DYES
NUR RAIHANAH BINTE MOHD HARION (F)QURAYISHAH BINTE BASARI (F)UMAA GOPINATHAN PILLAI (F)
SITI ZULAIHA BINTE MOHAMED GHAZALIE (F)
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
Hair Dye
PERMANENTSEMIPERMANE
NTTEMPORARY
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.
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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, sprays,
and foams.Typically brighter and
more vibrant than semi-permanent and
permanent hair color.
PERMANENT HAIR DYES
PERMANENT HAIR DYEWhat 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
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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).
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.
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 includeo Temporary skin irritation and allergieso Hair breakageo Skin discolorationo And unexpected hair color results
Bleaching
• For bleach to change the color of hair it has to be able to penetrate below the cuticle surfaceo 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
Bleaching• Bleaching is very damaging to hair as well as
emitting a sulfuric odoro Hydrogen peroxide breaks the sulfur bonds
which releases larger amounts of sulfuro This causes hardening, loss of mass, and
produces smell minimized by using low levels of peroxide in
cosmetic bleach
TEMPORARY HAIR DYES
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.
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
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!
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.
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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
References
http://www.dailymail.co.uk/health/article-2281413/Hair-dye-used-millions-women-linked-chemicals-cause-cancer.html
http://en.wikipedia.org/wiki/Hair_coloring#Temporary_hair_color http://chemistry.about.com/cs/howthingswork/a/aa101203a.htm http://www.onlymyhealth.com/what-difference-between-permanent-semi-permanent-h
air-color-1298015588 http://www.cancer.gov/cancertopics/factsheet/Risk/hair-dyes http://www.livestrong.com/article/211736-the-health-effects-of-hair-coloring/#
ixzz2ZPIsEluT http://en.wikipedia.org/wiki/Hair_coloring#Permanent_hair_color http://www.chemistrydaily.com/chemistry/Hair_dye