No abstract

Hair dye products are popular worldwide, and are most used by women in Europe and the USA. 1 Hair dyeing involves treating hair with natural and/or synthetic dyes to cover greying hair or to change the natural hair colour, according to the current fashion. Permanent hair dye products containing synthetic dyes are the most popular, but they cause allergic contact dermatitis in hairdressers and frequent users. 2 Synthetic hair dyes are also considered to be environmentally unfriendly and non-renewable.Natural hair dyes are becoming more and more in demand due to their conceivably greater safety, eco-friendliness and development from renewable resources. Accordingly, hair dye manufacturers and researchers have been investigating new sources of natural dyes and identifying their biological activities, colour characteristics, dyeing properties, formulations and safe use. [3][4][5] Natural dyes are colourants derived from plants, animals or minerals. Plants are the largest source of a wide variety of dyes given their extreme biodiversity, and many plants have traditionally been used as hair dyes in many