Removing stains from clothes is a quid pro quo affair -- for bleaching agents to work, the clothes have to be washed in warm water, which can ruin texture and colour. But now, researchers at Unilever Laboratories in the US and Holland claim to have developed a low-temperature bleacher (Nature, Vol 369, No 6482).

Bleaching agents work by converting stains, which generally consist of insoluble organic matter, into soluble oxides. Hydrogen peroxide, the cloth-friendly bleaching agent, can perform only above 60oC. However, the new compounds, claims Unilever, can make hydrogen peroxide effective at low temperatures. Unilever has already released two detergents containing the new bleaching agents.