Report of the Committee on the Dyeing Properties of Disperse Dyes

Four tests are prescribed for assessing the dyeing properties of disperse dyes on polyester fibres. The tests for migration and build‐up properties correspond essentially to those already developed for disperse dyes on other fibres. The critical temperature test classifies dyes in terms of relative rate of initial strike. The diffusion test is a simple means of comparing relative rates of penetration of dye into polyester. As with tests recommended in previous reports, these tests permit individual dyes to be rated on an A‐E scale for each property, with the exception of the critical temperature test where an A‐D scale is used.