Abstract

SAURA, A. Vanessa  and  GALINDO, Francisco. Use of indigo dye in Organic Chemistry teaching laboratory. Educ. quím [online]. 2016, vol.27, n.2, pp.133-138. ISSN 0187-893X.  https://doi.org/10.1016/j.eq.2015.11.005.

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.

Keywords : Indigo; Synthetic dyes; Vat dyeing; Laboratory practice.