Sodium Dithionite is a reductive bleaching chemical. It is also known as sodium hydrosulfite. Reductive bleaching is especially essential not only for bleaching but also for removing color from colored recovered paper and carbonless paper.

Many dyes used to color paper can be effectively destroyed by reductive bleaching chemicals. Sodium Hydrosulfite is known to be effective for color stripping and can remove many types of dyes.

Most of the acidic and direct dyes are permanently decolorized by Sodium Hydrosulfite or sodium dithionite because it breaks the azo groups. Some of the basic dyes are temporarily decolorized.

Sodium Hydrosulfite or Sodium Dithionite is also added in the yarn dyeing process with the indigo before denim fabric is made.