Utilización del colorante índigo en el laboratorio docente de Química Orgánica

Abstract

Indigo is one of the first examples of vat dyeing, being the reduction of the dye to its soluble form (leuco-indigo) the critical step of that process. A new method to address such reduction reaction has been tested which improves the overall results for the staining with this dye, at a didactic level in an Organic Chemistry laboratory practice. The innovation introduced consists of using a small sized round-bottom flask along with a balloon and a needle to release the inner overpressure. Compared to the traditional process, the new method allows for the reduction at lower temperatures (30 °C vs. 66 °C) and a more homogeneous fabric dyeing.