normally hair can grow 0.3mm each day,3days grow 1mm,one year can grow to 13.8mm.sunshine can promote hair growth,and each hair life is around 2-4years,and the longest can be 6 years.
we all know hair can have different kinds natural color,and the different color decided by melanin.the number of melanin is more,and density is heavy ,the hair will be more black.or hair will be more lighter,and will show different color under sunshine.
the root of hair is thicker,and hair tips is thin ,so the diameter is also different,can be divided into general hair,thick hair and fine hair.
natural hair style normally have four kinds,straight,wave,big curl and african curl.but the thicker or not is no relation to hair style.
the elasticity of hair is the ability to hair to pull to the maximum extent,still can restore its original state.a human hair can stretch 40%-60%,the expansion rate is determined by the cortex. The tension of the hair is refers to the hair to the limit without fracture strength. A healthy hair about can support the weight of 100-150 grams
hair main component is keratin hair, accounts for about 97%. And keratin is composed of amino acids.
oriental hair features hard weight is heavy, because it contains carbon, hydrogen, larger particles is more, so the color deep. For westerners to send qualitative characteristics are soft, gentle containing hydrocarbon is less, so with lighter color.
hair itself is no pH value, what we call the pH value refers to the hair around the secretion.
hair in alkaline cuticular layer will open, split, hair into a rough into porous, cannot achieve the effect of hot ZhengRan. In acid fold epidermis layer, keep the hair natural pH 4.5 ~ 5.5, hair texture, luster, easy to achieve the effect of marcel and dye hair.
normal daily can fall off 70-100 hairs, at the same time also has the same amount of hair regrowth. Different parts of the hair length associated with different growth cycle length. Their eyebrows and eyelashes growth cycle was only about 2 months, so short. Hair growth by genetics, health, nutrition, and hormone levels, and other factors.