Hello All, First post here and ill give you guys a quick breakdown, I am from Canada currently working as a Paramedic, my knowledge on chemistry probably isn't as superb as some of your, thus the reason I am here for some help! Currently my girlfriend are I are trying to figure out how some hair extension companies do a process called "de-pigmentation" to remove the colour from the hair. they claim to use no harsh chemicals in the process because that causes harm to the fibres within the hair causing it to break. One of the major companies claims: "The hair undergoes a delicate process of de-pigmentation lasting 15 - 20 days. The black pigments are slowly removed from inside the hair, not from the outside. The typical method of lightening/bleaching hair using ammonium derivatives damages the cuticle layer, thus compromising the hair's texture and condition! Our de-pigmentation process does not damage the hair and permits the removal of the black pigment without altering the quality of the hair. The color molecules are actually removed rather than bleached." they say they do a process of "gentle osmosis", similar to the de-pigmentation of Cashmere I am curious if anyone can give me a hand and maybe even discover as to how they do this? I understand the basics of osmosis, but I don't understand how they can literally remove the melanin within the cuticle of the hair. i have been messaging some Cashmere processing companies, but this all seems to be one big super secret, but one company did reply with this information: "Depigmentation Process. The depigmentation process consisted of a mordanting step followed by a bleching step and was carried out at the following experimental conditions: Mordanting Rinsing Bleaching FeSO4°E7H2O: 3.7 g/l Na2S2O4: 1 g/l HCHO (35-40%): 3 g/l L.R.: 1:20-1:50 pH(HCO2H): 3 1h 85°C Warm water 20 min room temperature water 20 min Na4P2O7: 10 g/l EDTA: 2 g/l H2O2: 1-8 vol L.R.: 1:20-1:50 pH: 9 30 min 85°C Different concentrations of hydrogen peroxide in the bleaching bath were tested. Sample A (16.5 µm) was depigmented at a fibre liquor ratio of 1:20 using an Ahiba –Turbocolor 100 Laboratory dyeing apparatus. Concentrations of 2-4 and 8 vol of hydrogen peroxide were used. Sample B (17.1 µm) was depigmented at a fibre liquor ratio of 1:50 in flasks placed in a thermostatically controlled shaking water bath (Grant OLS200). Concentrations of 1-2-3-4-5- 6-7-8 vol of hydrogen peroxide were used." I know they use a very weak based hydrogen peroxide, but would that still not harm the hair? Thank you for any help!