GB/T 33795-2017 "Reactive Dyes — Determination of the Rate of Hydrolysis" applies to the determination of the hydrolysis rate of reactive dyes and specifies the specific test method. The dye sample is placed in a buffer solution at a specific temperature and pH for reaction. Samples are taken at different time points, and a high-performance liquid chromatograph is used to separate and detect the hydrolysis products and unhydrolyzed dye. The hydrolysis rate is determined by calculating the residual proportion of the dye. The standard clarifies requirements for sample handling, chromatographic conditions, and data calculation, providing a basis for evaluating the application performance of reactive dyes.