Thiourea dioxide is currently out of stock. Sodium hydrosulphite(‘hydros’ or ‘spectralite’) can be used in the same way and in the same quantities.
Sodium hydrosulphite, also referred to as ‘hydros’ or under the brand name spectralite is an effective, oxygen-reducing agent for use in indigo and woad (vat) dyeing.
Used in conjunction with sodium carbonate (‘soda ash’) it is reliable and straightforward to use.
Can be used as an alternative to thiourea dioxide (‘thiox’).