In medium temperature dyeing, under the premise of high light fastness, the compatibility of the dyes is excellent, the SERF value of the three dyes is less than 5%, and the dyeing tolerance of the dyes is excellent. The change of process parameters (temperature, pH value, bath ratio, time) during dyeing is minimal, and the size samples are consistent, and the one-time success rate is high, which is especially suitable for sensitive colors with dyeing depth of 0.1-1% and sun
fastness index.