Colour Restore Iced Platinum Hair Toner with Anti-Yellow Infusion is a new way to control pigment levels within colour treated hair. Keratin, the hairs' natural protein, is yellow in colour. When hair is bleached or heavily lightened the natural pigment is stripped away and the keratin exposed, this is why hair can look 'brassy' or 'yellow'. Colour Restore replenishes and returns hair colour to its former glory without the need to use a peroxide or ammonia based colourant. Simple to use, just rinse through (like a shampoo) to maintain tone or leave in for up to 25 minutes for deeper tonal results. Using a concentration of complex violet tone, Colour Restore Iced Platinum counteracts yellow or brassy tones to create crisp, cool, pure white blonde shade. Contains no ammonia, no peroxide, no harsh chemicals. Creates perfect iced white results in naturally high grey or bleached base shades. Replenishes cool tones in highlighted hair. Can be used immediately after perming, colour removal, straightening or bleaching.