HAIR CARE: HAIR CARE Assoc. Prof. Dr.Pleumchitt Rojanapanthu Pharmacy Department, Faculty of Pharmacy Mahidol University, Bangkok, Thailand


Slide2: Women from all around the world choose hair styles to their type of hair. Hair our personalities, whichever race we come from


Slide5: Hair Getting to know hair Types of hair Hair structure Hair growth cycle


Slide6: Hair Color Physical properties of hair Chemical properties of hair Hair (con.)


Slide7: Shampoos Conditioners “2 in 1” shampoos Hair sprays Hair Care Products


Slide8: Hair Care Products (con.) Hair gels Perming solutions Hair dyes etc. General remarks about product development


Getting to Know Hair: Getting to Know Hair All Land mammals (including) humans have hairy skins Hair characteristics are inherited directly from our parents hair color hair type The same as your eyes & your skin


Slide10: Human are covered all over in hair except on the palms of hands the sole of the feet the lips Hair is most obvious on the head and face including the nose and ears in some people the armpits / the groin the chest and legs (in men) Hair distribution


Slide11: Average : 100,000-150,000 hair follicles Baby’s head : 1,100 follicles/m2 Age 25 : ~ 600/m2 Age 30-50 : ~ 250-300/m2 Each follicle grow about 20 new hairs in lifetime Each new hair grows several year 1 meter Each hair falls out eventually and is replaced by a new hair How much hair do we have


Slide12: Different people have hair that differs in color, length diameter, distribution Influence factors : Racial type Age Variation in human hair


Slide13: Types of hair 3 types Lanuga hair develops on an unborn baby 3 months after the baby’s conception fine and soft grows all over the body, at the same rate shed about 4 weeks before the baby is due to born


Slide14: Vellus hairs short hair, only 1 or 2 cm. Long contains little or no pigment follicle doesn’t have oil glands never produce any kind of hairs


Slide15: long hairs that grow on the head, body arms and legs produced by follicles with sebaceous glands people inherited a tendency to baldness the hair become thinner and shorter until look like vellus hair Terminal hairs


Slide16: d Vellus hairs on a woman’s chin. These are normal when female hormones decline, hairs on the chin can grow as strongly as terminal hairs


Slide17: Variation with age Childhood Newly born full-term baby Terminal hairs grow on the scalp &eyebrows All the rest of hair is vellus hair Baby grows the hair on the head grows Hair growth begin at the forehead then extends to the back


Slide18: 2-3 months old baby - first hair may be shed naturally over an area on the back of the head - was thought to be head rubbing Hair broken by rubbing - may found in other part of the head


Slide19: Naturally occurring hair loss, which begins at age 8-12 weeks Mosaic patterns starting to develop; the beginning of hair streams can also be seen


Slide20: all hairs on the head grow at the same rate head carries an even covering of hair individual hair begin to grow independently grow at different rate and different cycles First year baby


Slide21: unruly hair which sticks straight up natural curls hair without pigment Features of children hair


Slide23: Before puberty : - Scalp carries a mixture of short vellus-like hair and longer terminals hairs together with various ‘in between’ hair At puberty : - Terminal hairs begin to appear in the armpit, groin & legs chin, chest & forearm Adolescence


Slide24: most of scalp hair are terminal hairs thicker in diameter After puberty :


Slide25: the hairs continue to grow strongly/hair at 80 = at 50 the hairs get thinner as the age/at 80s only a few wisps remain Middle age and beyond


Slide26: a tiny cup-shaped pit burried deep in the fat of the scalp follicle is the point from which the hair grows well supplied with minute blood vessels temperature is normal body temperature Hair Structure Hair follicle


Slide27: temperature is not affected by cold or hot water the rate of growth depends on the amount of natural light : growing a little faster in winter when the days are short Hair Structure (con.)


Slide28: Hair follicle Hair bulb Hair shaft Hair bulb - lines in side the hair follicle - is a structure of actively growing cells - produce a long fine cylinder of hair - new cells are continuously produced in the lower part of the bulb


Slide29: (a) Longitudinal section of a hair within its follicle. (b) Enlarged longitudinal section of a hair.


Slide30: (c) Enlarged longitudinal view of the expanded hair bulb of the follicle which encloses the matrix, actively dividing epithelial cells that produce the hair.


Slide31: (d) Cross section of a hair and hair follicle.


Slide32: (e) Photomicrograph of scalp tissue showing numerous hair follicles (24 X).


Slide33: Scanning electron micrograph showing a hair shaft emerging from a follicle at the epidermal surface. Notice how the scalelike cells of the cuticle overlap one another (1500 x).


Slide34: can be seen above the scalp consist mainly of dead cell Keratin + binding material + small amount of water terminal hairs are lubricated by natural oil (sebum) produced by sebaceous glands high level of hormones (androgens) high level of sebum The Hair Shaft


Slide35: scales growing over the youngest part (closet to the scalp) are smooth and unbroken further along the hair have been damaged by cosmetic treatments and by mistreatment : (over-energetic brushing) Nature of cuticle


Slide36: Nature of cuticle (con.) little by little, they may break away : “weathering” healthy cuticle is more than just a protective layer intact cuticle cells are smooth, glossy, and reflect light from their surface (black hair reflects less light than blond hair)


Slide38: The cuticle scale on a normal hair (electronmicrograph)


Slide39: Another normal hair - but this came from one of our nearest relatives an orangutan! A perfect hair seen under the electron microscope


Slide40: keratin chains link by : disulphide bond and hydrogen bonds disulphide bonds can be changed by chemical methods : perming and relaxing permanent Hair shape


Slide41: hydrogen bonds can be easily broken apart whenever the hair is wetted and form again as it dries when they break the shape of hair changes wet hair is wound on the roller, the dried hair keep the roller shape temporary Hair shape (con.)


Slide42: European around 70-90 micron Asian around 120 micron People have average hair around 100,000 – 150,000 hairs Hair dimensions


Slide43: individual hair form inside a hair bulb deep in hair follicle is tiny but powerful factory each hair grows during many years shampooed, conditioned, cut, blown dry, exposal to the sun and wind, colored, bleached, permed none of these affected the hair growth Hair growth cycle


Slide44: the hair spontaneously falls out the follicle rests for a little while and starts to produce a new hair Hair growth cycle (con.)


Slide45: anagen : the growing phase (~1000 days) catagen : the intermediate phase (~10 days) telogen : the shedding phase (~100 days) Stage of the hair cycle


Slide46: last between 3-7 years without interruption roughly 1 cm/month > 1 meter faster rate in winter than summer melanin is made in hair bulb throughout this phase Anagen (the growing phase)


Slide47: less pigment is made in older people, hair cycle becomes shorter follicles gradually give up producing long, strong hair : hairs become thinner and shorter thinning of the hair degree of baldness Anagen (con.)


Slide48: short resting phase : 2-4 weeks no pigment is made follicles stop producing hair the base of follicle moves upwards towards the surface of the skin Catagen (the intermediate phase)


Slide49: last for 3-4 months new hair begin to grow from the hair follicle as it grow s upwards the old hair will be shed naturally or easily be pulled out Telogen (the shedding phase)


Slide50: at anytime around one in ten of the follicles at individual’s head is in the shedding phase shedding is part of normal process of the replacement of old hair with new hair new hair emerges from the same opening as the old one Telogen (con.)


Slide51: The hair follicle cycle


Slide53: Each of these long hairs has been growing  for at least six years: eventually it will fall out spontaneously; this growth and fall makes up the hair cycle


Slide54: Naturally blond hair: this lady's anagen phase lasts for about  four years


Slide55: Hair this long must have been growing for seven or eight years: just look at its beautiful condition


Slide56: 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 job 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


Slide57: A method of measuring the rate of hair growth: both cut hairs and newly emerging hairs can be seen


Slide58: Electronmicrograph showing new hairs emerging from the hair follicles of the scalp


Slide59: general health and nutritional factors starvation or crash diet loosing hair in 6-10 weeks alcoholic people have poor hair some minerals may particularly important for hair growth What controls hair growth ?


Slide60: lack of Zn : produces only fine, sparse hairs even lost their hairs Vit B : known as panthenol, plays a part in hair growth, improves physical properties (elasticity, strength and gloss) of the hair shaft Hair growth (con.)


Slide61: thyroid hormone speeds up growth in resting hair follicles steroids taken by mouth slow down the growth Hormones :


Slide62: Androgen : the most important factor regulating hair growth, thickness of hair shaft : changes vellus - like hair terminal hair oestrogen : slow down hair growth during growth period, make the period longer Hormones (con.)


Slide63:  This boy has a zinc deficiency, and his hair is very thin and sparse; after treatment his hair is growing more strongly


Slide64: Pigmentation Melanin : - produced by melanocytes at growing phase (anagen) - spread out throughout the cortex, the more near outer edge lie along the amino acid chains - does not protect the harmful effect from sunlight - is found in 2 forms Hair Color


Slide65: 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 Pigmentation (con.)


Slide67: Melanin granules in the cortex of a hair


Slide68: the arrangement of keratin bundles the way the large bundles of keratin are arranged within each hair shaft the position of hair bulb : African hair bulb may lie to the side of the follicle, so the hair shaft grows out of the follicle at an acute angle Factors affecting hair structure :


Slide69: irregular growth in the hair bulb : if it varies slightly to one side or the other, hair may grow wavy the shape of the follicle : whether it is straight or curved the number of twists per unit length : African hair has 12 times as many twist per cm. as Caucasian hair Factors affecting hair structure (con.)


Slide70: Strength Elasticity Static electricity Moisture content Porosity Texture Physical properties of hair


Slide71: a single hair can support a load of about 100 gm keratin protein of the cortex responsible for the hair strength keratin is a protein chains contain high concentration of an amino acid called “cystine” matrix contains high level of cystine Hair strength


Slide72: each cystine unit contains 2 cysteine amino acids in different chain the chains are linked by two sulphur atoms, forming a very strong chemical bond “disulphide linkage” many disulphide bonds form down the length of the keratin chains Hair strength (con.)


Slide73: Chemical bonds within the hair maintain its shape


Slide74: one of the most important properties can resist forces that could change its shape, volume and length lest spring back to its original form without damage wet hair can increase the length up to 30% and return to original length when it is dried Elasticity


Slide75: elasticity of hair depends on the long keratin fibers in the cortex chemical treatment can alter the cortex and change the hair elasticity Elasticity (con.)


Slide76: poor elasticity : - stretch only to a limited extent - will break easily - cannot be permed satisfactorily natural sunlight and artificial UV light damage chemicals of hair and its elasticity Elasticity (con.)


Slide77: Tensile and Elasticity of hair


Slide78: Static electricity rubbing drug hair / brushing / combing builds up static electric charge the charges tend to push each other apart charged hair never lie smooth against each other “ fly away ” hair stands out from the head


Slide80: Moisture content : Heat and humidity more moisture less static electricity collapse Heat and dryness less moisture more static electricity more volume


Slide81: - wet hair swell cortex / lift cuticle scales - hair surface temporaly loses its smoothness - wet hair more friction matting and tangles (over vigorous shampoo) Moisture content (con.)


Slide82: cuticle covering cortex is intact : almost water proof (very little water can go in and out) shampoos do not damage the cuticle treating the hair (permed or tinted) Porosity Normal hair


Slide83: temperature / applying an alkaline lotion separate the scale allowing chemicals to go inside after processing scales close up Porosity (con.)


Slide84: processing many times / too much blow drying/ too high temperative / effect of sun and wind the scales lose the tightness the porous damage cuticle is fragile develop split end Porosity (con.)


Slide85: the damage is worse as the time goes by the greater the damage, the more the cortex swells with water the more water loses when it dries repeated wetting and drying of the cortex, gradually weakens the hair Porosity (con.)


Slide86: the larger the hair diameter the coarser it will feel different people’s hair naturally feel different soft / hard / silky / wiry effected by degree of weathering of hair Texture


Slide87: Texture is affected by what has been put on it : - spray : makes different feeling - conditioner : feel soft and smooth - conditioner with silicone : protect the hair cuticle - damage to cuticle : alter the hair texture Texture (con.)


Slide88: Chemistry of Hair Keratinization process in the follicle keratin + water soluble substances : pentose, phenols, uric acid, glycogen, glutamic acid, valine, leucine


Slide89: Chemistry of Hair (con.) Keratin is composed of amino acid 18 out of 25 normal amino acids are found in keratin


Slide90: Organization of hair protein sets up by bonding in 3 ways : Chemistry of Hair (con.) between parallel peptide chains I Formation of H-bonds


Slide91: between acidie and basic side chain Chemistry of Hair (con.) II Formaton of salt linkage


Slide92: Chemistry of Hair (con.) amino acid contains two amino and two carlygl groups link together by a disulphide bond III Formates of disulphide linkages


Slide93: Structure for a- keratin