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

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

5. Hair Getting to know hair Types of hair Hair structure
Hair growth cycle

6. Hair (con.) Hair Color Physical properties of hair
Chemical properties of hair

7. Hair Care Products
Shampoos
Conditioners
“2 in 1” shampoos
Hair sprays

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

9. 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

10. Hair distribution 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)

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

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

13. Types of hair develops on an unborn baby
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

14. 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

15. Terminal hairs 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

16. 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

17. 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

18. 2-3 months old baby on the back of the head
- 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

19. 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

20. First year baby 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

21. Features of children hair
unruly hair which sticks straight up
natural curls
hair without pigment

23. Adolescence 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

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

25. Middle age and beyond 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

26. Hair Structure Hair follicle 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

27. Hair Structure (con.) 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

28. 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

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

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

31. (d) Cross section of a hair and hair follicle.

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

33. 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).

34. The Hair Shaft 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

35. Nature of cuticle 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)

36. 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)

38. The cuticle scale on a normal hair
(electronmicrograph)

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

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

41. Hair shape (con.) 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

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

43. Hair growth cycle 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

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

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

46. Anagen (the growing phase)
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

47. Anagen (con.) 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

48. Catagen (the intermediate phase)
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

49. Telogen (the shedding phase)
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

50. Telogen (con.)
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

51. The hair follicle cycle

53. 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

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

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

56. 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

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

58. Electronmicrograph showing new hairs emerging from
the hair follicles of the scalp

59. What controls hair growth ?
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

60. Hair growth (con.) 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

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

62. Hormones (con.)
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

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

64. Hair Color Pigmentation phase (anagen)
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

65. Pigmentation (con.) 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

67. Melanin granules in the cortex of a hair

68. Factors affecting hair structure :
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

69. Factors affecting hair structure (con.)
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

70. Physical properties of hair
Strength
Elasticity
Static electricity
Moisture content
Porosity
Texture

71. Hair strength 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

72. Hair strength (con.)
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

73. Chemical bonds within the hair maintain its shape

74. Elasticity 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

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

76. Elasticity (con.) 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

77. Tensile and Elasticity of hair

78. 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

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

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

82. Porosity Normal hair 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)

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

84. Porosity (con.) 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

85. Porosity (con.) 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

86. Texture 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

87. Texture (con.) 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

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

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

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

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

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

93. Structure for a- keratin