HAIR CARE

1. HAIR CARE Assoc. Prof. Dr.Pleumchitt RojanapanthuPharmacy 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 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

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 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

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 - 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 • allhairs 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 thearmpit, groin & legs chin,chest & forearm

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

25. Middle age and beyond • thehairs 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) • lastfor 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