Hydrosulfite s. Dithionite

Hydroquinones s. Quinols Hydrosulfite s. Dithionite Hydroxamic acid derivatives... 

The sulfur-containing anion, S204, formed by the reduction of HSOj with zinc, has been called at various times hypomlfite, hydrosulfite, and dithionite. The latter name is that currently assigned to the ion, together with the structural formula O—S—S—02, An alternate structure,... 

In the two-phase process dyes and chemicals are applied in separate steps first dyes and thickener ( solid phase ) are printed, then chemicals and auxiliaries are added as an aqueous solution by padding. Sodium dithionite (Hydrosulfite) is used as reducing agent, and steaming time is kept short (20-40 s). For stabilized reducing agents, see [5, p. 296-298],... 

Of special interest to the dyestuff chemist is the 9,10-dihydroxyanthracene stmcmre since its red, water-soluble sodium salt forms the basis for applying anthraquinone dyes to cotton (qv). Because the reductions were originally carried out in large mbs or vats, the operation became known as "vatting" and the dyes as "vat" dyes. The most commonly used reducing agent is alkaline hydrosulfite, also known as dithionite (Na S O]). Use of thiourea... 

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