摘要 |
Method of stabilising metallic lithionites comprises incorporating in the diethionite, during or after its manufacture, a small amount (0.2-2.0 wt.%) of one or more carbonylated aromatic cpds., esp. vanillin, ethyl vanillin otherwise known as 3-ethoxy 4-hydroxy benzenedehyde (sic), and benzoin, otherwise known as phenyl benzoyl carbinol. The compsn. may also contain a free flowing additive. The compsn. obtd. is prepared in the anhydrous state. Used as bleaching agent in the paper paste industry and as bleach or colourant in the textile industry. According to the amount of additive varying amounts of dithionite can be stabilised against reaction with moisture and air for indefinitely long periods. |