PROCESS FOR DYEING POLYTRIMETHYLENE TEREPHTHALATE FIBRES AND USE OF THUS DYED FIBRES

摘要

A process is disclosed for dyeing polytrimethylene terephthalate fibres (PTMT fibres). The PTMT fibres are treated in an aqueous bath containing at least one dispersion dye at or below the bath boiling temperature. The process is characterised in that the PTMT fibres are dyed without pressure and without carriers. Dyeing starts at a bath temperature between 20 and 50.degree.C, the temperature is brought within 20 to 90 minutes, preferably within 45 minutes, up to the bath boiling temperature or up to a dyeing temperature at the most 20.degree.C lower than the bath boiling temperature, dyeing continues for at least 20 minutes at the dyeing or boiling temperature, preferably for 30 to 90 minutes, and the temperature is then brought down to 20 to 50.degree.C, preferably at a cooling rate of 1.degree.C per minute, so that at least 95% of the dye contained in the bath is absorbed by the PTMT fibres, and the dispersion dye impregnates the fibres at least down to a relative depth equal to 5% of the diameter of the fibres to be dyed.