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Hair Color Pigmentation Melanin : - produced by melanocytes during the growing phase (anagen) - spread out throughout the cortex, more near outer edge where it lies along the amino acid chains - does not protect from the harmful effect of sunlight - is found in 2 forms


- Eumelanin : dark pigmented which predominates in black and brunette hair/oval shape - Phaeomelain : lighter pigment, found in red and blond hair/smaller, partly oval and partly rod- shape


Melanin granules in the cortex of a hair


Range of color produced by melanins: yellow, brown, red, black Black hair: contains mostly eumelanin Grey hair: contains only little melanin White hair: contains no melanin Unpigmented hair: look yellow when they first grow (color of the keratin), later turn white


Seriously weathered hair: she needs to see a hair stylist, urgently!


This woman's coloration is typically Celtic: her hair pigment consists overwhelmingly of phaeomelanin, her skin is freckled and tends to bum easily, and her eyes are blue


Hair Care Hair condition: Good condition - shiny : ability to reflect the light - easy to manage - healthy appearance - just look good, shine and body


Factors that influence hair condition: - enough protein in diet (starvation or anemia due to lack of protein in the diet can damage the hair) - lack of protein: the color change from black to gingery-red - cuticles should be intact - cortex has not been affected by heat or chemicals - no cake with grease and old hair spray


Caring for your hair - regularly cleaning - using good quality products - remember to condition it well - cut regularly by skilled stylist - prevent weathering effects


- changing color by experienced hair technician - perming hair: improving condition first - after perming: more attention to conditioning your hair - don’t repeat the perm too often


Hair this long must have been growing for seven or eight years: just look at its beautiful condition


The straight blonde hair of this tanned young woman is naturally sun-bleached, and reflects light well


This man is head of a religious cult which requires its leader to be able to grow his hair long enough to reach the ground: his anagen period is probably around ten or twelve years. As he grows older and the anagen period shortens, he may lose his position The golden hair of the imprisoned fairy-tale princess Rapunzel was long enough to allow her lover to climb it in order to reach her in her tower - a demonstration not only of the length of anagen in Rapunzel, but also of the inherent strength of hair


Cosmetic Hair Treatment The most important treatments: Perming Coloring Stylist and technician: - expected to have a thorough understanding of: hair structure hair growth cycle continuing care of hair


- need a working knowledge of the disorders of the hair and scalp - knowing the chemistry of hair care products - the way in which they protect the hair


- the science that underlies the various cosmetic procedures - looking at the history of a client’s hair - examining the hair condition - deciding what is or is not possible to be done


Styling hair - temporarily or permanently altering its shape


Temporary - no chemical reaction in the hair - some weak hydrogen bonds are broken - re form in the newly positioned hair as the water evaporates by allowing wet hair to dry while twisted around the form - heat’s a great enemy of hair - dryer must be used with great care


- highest setting of a hair dryer will reach the temperature of boiling water - curls produced by setting are tight - all hair gradually absorbs moisture from the air - as the hydrogen bonds break it will in time re form and style will be lost


Perming Hair - disulphide linkages in hair are formed when the hair cells harden into keratin in the hair follicle - disulphide bonds keep the hair shaft in shape - disulphide bonds have to be broken down and re formed into different pattern - chemical changes to disulphide bonds are permanent


The history of perms - people have been trying to lure straight hair into waves and curls for thousand of years - only for temporary waving - first truly permanent waves became available in 1920


- the waving lotion was activated by heat from an electrical device for each curl - no thermostat: heavy uncomfortable - perms were harsh, dry, tight frizzy curl difficult to manage


- in 1946, the “cold wave” was introduced - this was basically the perming process we use today - the unpleasant heat and weight of the old appliances were completely eliminated - the hair could be waved closer to the scalp


Modern perm - a permanent wave is a process that create a curl in the hair shaft by altering its internal chemical structure - the curls cannot be destroyed except by further chemical treatment - some hair can stand up to repeated perming quite well, some can’t


Factors that influence the perm - the basic nature of hair - its past history of chemical treatments - hair that has had a long history of perming combined with tinting or bleaching may have become so damaged as to be near the limit of what it will tolerate


pH and hair - alkali  pH > 7 - acid  pH < 7 - hair is swollen in alkali solution: the scales of the cuticle are lifted - in a slightly acid solution, the scales lie smoothly and soft - in a strong acid or alkali solution, the keratin protein starts to break down


An excellent example of 'setting‘ to give a spectacular effect to already curly hair


A perfect example of hair which has been given body and volume by perming


This permed and bleached long hair looks good at first glance, but the hair is dry and has no lustre


Dry, lifeless hair that has been repeatedly permed: the hair has also been bleached, and the darker roots are growing out in much better condition: at this stage it can no longer take a perm because virtually all the disulphide bonds have been broken


The perming process - hair is first washed, wound on to some kind of former - perm lotion (alkali lotion of pH~9) is applied - the cuticle slightly opens up - the lotion flows under the cuticle and into the cortex


- the lotion reacts with keratin of the cortex - disulphide bonds between protein chains are broken - the hair swells, soften and can stretch to take up the shape of the formers - after a while, the perm lotion is thoroughly rinsed - neutralizing lotion is applied and thoroughly rinsed


- the broken disulphide bonds are reformed - the hair is harden into its new shape * failure to rinse and neutralize properly can lead to many problems: scalp irritation and damage to the structure of the hair shaft


What happens during perming process? reducing agents in alkali lotion (ammonium thioglycollate)  breaking disulphide linkage (joins the pairs of cysteine units)  keratin softens and swells  Softened hair is then put into its new shape


 cysteine linkages slip past each other and realign themselves with new cysteine partners  Neutralizing lotion is then applied (oxidising agents i.e. hydrogen peroxide)  cysteine units link together into pairs again, hardening the hair and giving its new permanent shape


After perming - the hair continue to form new bonds for 2 or 3 days - the hair should not be shampooed during those few days - shampooing may interrupt this “curling” process: shampooing spoils the carefully constructed curls and could even lead to hair damage


Hair breakage at the back of the neck associated with relaxing  and traction


Grossly over-permed hair: repeated perming will produce dry, damaged hair unless very expertly performed


Over-bleached hair: the damage is all too obvious


Relaxing (straightening) hair - the chemistry of relaxing process is identical to that of perming - breaking of disulphide linkages - reforming of the hair shape in a straighter arrangement - following by re-making of the linkage


This lady's hair has been gently relaxed


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