Most commonly occurring carpet stains are caused by the dyes present
in household items including food items, beverages, deodorizers, detergents
etc. Many of these stains become permanent unless treated IMMEDIATELY.
Any spills must be completely blotted using soft, white, absorbent material.
For dye stains, hot transfer method is the most effective: the affected
area must be covered with a towel treated with a surfactant and a hot
iron applied over it. Under the heating and lubricating influence, the
fibers swell and release the culprit dyes, which haven't yet had time
to settle into the fiber. Take care to frequently use fresh towels as
required.
In case of disperse dyes like those present in mustard and herbal tea,
bleaching agents must be used.
This treatment might also cause some discoloration or fading of the original
dyes in the carpet which might require re-dyeing.