Method for dyeing linen fabric/fibres by reduced dye at high temperature

The invention relates to a method for dyeing linen fabric/fibres by a reduced dye at a high temperature. The method comprises the following steps of: (1) dye selection, namely, in the existence of reduced dyes, a reducer, NaOH and a dye high-temperature stabilizer, completely reducing the dyes into leuco bodies, and then determining the absorption curve of the completely-reduced-state dye solution before and after the treatments via temperature-rising, high-temperature and constant-temperature treatments, so as to find the reduced dye suitable for high-temperature drying; and (2) a dyeing process, namely, preparing the suspension of the reduced dye in a dye vat according to proper dyeing conditions including a bath ratio, a dye amount, the reducer, sodium hydroxide, and the high-temperature stabilizer, adequately reducing and then adding the linen fabric, heating, raising temperature and dying at 100-160 DEG C, then washing by cold water, developing via the complete oxidation of H2O2, performing soap-boiling in liquid soap, washing by hot water, drying and the like. The linen fabric dyed via the high-temperature dyeing process aforementioned is bright in colour, high in colour yield, and especially great in dye permeability.