| Abstract: | The paper describes a study of many factors which play a significant part in the dyeing of texturised-polyester yarn at high temperatures. The variables chosen for study are the selection of disperse dyes to give the desired fastness properties, coverage of dyeing-substantivity differences before, during and at the end of the dyeing process. The effects of different types of dispersing agents on dispersion properties and the selection and behaviour of different types of ‘carrier’ suitable for high-temperature dyeing are also considered, the latter in relation to levelling, dye yields, ability to compensate for small differences in dyeing temperature, coverage of yarn variations, minimisation of dye and oligomer crystallisation at the end of dyeing and the stability of the ‘carriers’ themselves. The formation and behaviour of oligomer have also been investigated. Factors governing the choice of optimum dyeing cycles for polyester yarn are also reviewed. |
