PROPERTIES OF THE HAIR AND SCALP

1. PROPERTIES OF THEHAIRANDSCALP

2. What is the technical term for the study of hair, and it’s diseases and care? TRICHOLOGY

3. A mature strand of hair is divided into two parts: • HAIR ROOT 2. HAIR SHAFT

4. STRUCTURES OF THE HAIR ROOT The Follicle – tube-like pocket which protects the root Hair Root-the part located below the surface of the scalp Hair Shaft – the portion of the hair that projects above the skin The Hair Bulb – lowest part of the hair strand. Fits over the papilla The Arrector Pili Muscle – tiny, involuntary muscle. Causes goose bumps Sebaceous Glands – oil glands of the skin, connected to hair follicles. Produces oil called sebum which lubricates the hair and skin Epidermis – top layer of the skin. Dermis – the layer of the skin under the epidermis

5. STRUCTURE OF THE HAIR SHAFT There are three main layers of the hair shaft: Cuticle Cortex Medulla

6. CUTICLE • Outermost layer of the hair. • Consists of overlapping layer of cells that look like shingles on a roof • Protects the cortex • Responsible for creating the shine and the smooth, silky feel of healthy hair

7. CORTEX • Middle layer of the hair • Contains melanin pigment • 90% of total weight comes from the cortex • Elasticity and natural colour located in the cortex

8. MEDULLA • Innermost layer • Quite common for very fine and naturally blonde hair to entirely lack one • All male beard hair contains a medulla • Medulla is not involved in salon services

9. CHEMICAL COMPOSITIONOF HAIR • Composed of a protein called KERATIN • 90% protein – made up of long chains of amino acids which in turn are made of elements • COHNS elements are the 5 elements that make up human hair and are found in the skin and nails • CARBON, OXYGEN, NITROGEN, SULFUR and HYDROGEN

10. SIDE BONDS OF THE CORTEX • 3 different side bonds • HYDROGEN • SALT • DISULFIDE BONDS • Side bonds hold the keratin fibres and are responsible for the strength and elasticity of human hair • Important for roller sets, thermal styling, perming and chemical relaxing

11. HYDROGEN BOND • Is a weak physical side bond • Easily broken by water or heat • Eg. Wet set (roller set)

12. SALT BOND • Also weak, temporary side bond • Easily broken by strong alkaline or acidic solutions • Eg. Some mild permanent waves

13. DISULFIDE BOND • Chemical side bond that is very different from the other two. • Are much stronger, far fewer of them • Disulfide bonds joins to sulfur atoms to create a cystine • Not broken by heat or water • Thio perms break disulfide bonds which are then reformed by thio neutralizers • Hydroxide chemical hair relaxers break disulfide bonds and they can never be reformed

14. HAIR PIGMENT • All natural hair colour is the result of the pigment located within the cortex called MELANIN. • MELANIN are tiny grains of pigment that give natural colour to hair. • There are two different types of melanin: Eumelanin and Pheomelanin

15. EUMELANIN • Provides brown and black colour to hair

16. PHEOMELANIN • Provides colours ranging from red and ginger to yellow/blonde tones.

17. HAIR ANALYSIS Different types of hair react differently to the same service Essential that a thorough analysis be performed prior to all salon services The four most important factors to consider in hair analysis are: texture, porosity, elasticity and density. Also consider growth patterns and dryness versus oiliness

18. HAIR TEXTURE • Is the thickness or diameter of the individual hair strand. • Can be classified as coarse, medium, or fine • It is not uncommon for hair from different areas of the head to have different textures.

19. Coarse Hairis stronger than fine hair and usually requires more processing time and is often more resistant to processing. Medium Hair texture is the most common and is the standard to which other hair is compared. Medium hair does not pose any special problems or concerns Fine Hair has the smallest diameter and is more fragile, easier to process, and more susceptible to damage from chemical services than coarse or medium hair.

20. HAIR DENSITY • Measures the number of individual hair strands on 1 square inch of scalp. • Can be classified as thin, medium or thick/dense. • Different from hair texture in that individuals with the same hair texture can have different densities

21. HAIR POROSITY • Is the ability of the hair to absorb moisture • Healthy hair with a compact cuticle layer is naturally resistant • Porous hair has a raised cuticle layer that easily absorbs moisture

22. HAIR ELASTICITY • Is ability of the hair to stretch and return to its original length without breaking • Is an indication of the strength of the side bonds that hold the hair’s individual fibres in place. • Wet hair with normal elasticity will stretch up to 50% of its original length and return to that same length without breaking • Dry hair stretches about 20% of its length • Hair with low elasticity is brittle and breaks easily

23. GROWTH PATTERNS It is important when shaping and styling hair to consider the hair’s growth patterns. Most hair follicles grow at an angle other than 90 degrees, and most hair grows in a direction other than straight out from the head. These growth patterns result in hair streams, whorls, and cowlicks.

24. Hair Streamis hair flowing in the same direction, resulting from follicles sloping in the same direction. Two streams flowing in opposite directions form a natural part in the hair.

25. Whorlis hair that forms in a circular pattern, as on the crown. A whorl normally forms in the crown with all the hair from that point growing down.

26. Cowlickis a tuft of hair that stands straight up. Cowlicks are usually more noticeable at the front hairline, but they may be located anywhere.

27. DRY HAIR AND SCALP • Can be caused by inactive sebaceous gland, and aggravated by excessive shampooing or dry air, such as during winter or in a desert climate. • Lack of sebum leads to hair that appears dull, dry and lifeless • Should be treated with products that contain moisturizers and emollients • Frequent shampooing should be avoided, along with the use of strong soaps or products with a high alcohol content

28. OILY HAIR AND SCALP • Caused by improper shampooing or overactive sebaceous glands, and is characterized by a greasy build up on the scalp and an oily coating on the hair • Can be treated by properly washing with a normalizing shampoo • A well-balanced diet, exercise, regular shampooing, and good personal hygiene are essential to controlling oily hair and scalp

29. HAIR GROWTH • 2 main types of hair found on the body: VELLUS and TERMINAL HAIR VELLUS: also known as lanugo • Short, fine and downy • Not pigmented and almost never has a medulla • Found nearly everywhere except the palms of the hands & soles of the feet • Vellus hair helps in the efficient evaporation of perspiration

30. TERMINAL HAIR: • Is the long hair found on the scalp, legs, arms, and bodies of males and females. • Coarser than vellus hair and with the exception of grey hair, it is pigmented • Usually has a medulla and is easily distinguished from vellus hair by its dark colour and coarse texture • All hair follicles are capable of producing either vellus or terminal hair, depending on genetics, age and hormones

31. GROWTH CYCLES OF HAIR Hair growth occurs in cycles. Each complete cycle has three phases that are repeated over and over again throughout life. Anagen Catagen Telogen

32. Factors that Influence Hair Growth • Diet • Blood Circulation • Emotion Disturbances • Endocrine Glands • Medication • Heredity • Environment • Products • Appliances