GB/T 2396-2013 "Disperse Dyes – Determination of Fixation – Thermosol Dyeing Method" specifies a method for determining the fixation of disperse dyes using the thermosol dyeing process, which is applicable to evaluating the related properties of disperse dyes. The test requires controlling the dyeing temperature and time with a thermosol dyeing machine. After dyeing, the fabric is subjected to soaping treatment using a high-temperature and high-pressure dyeing sample machine or a color fastness to washing tester. A colorimeter is then used to measure the color difference of the dyed fabric before and after soaping, and the fixation rate is calculated. This provides technical support for optimizing dye application processes.