This standard specifies the general method for determining the melting point of dye intermediates using the capillary method, applicable to the inspection of crystalline or powdered dye intermediates. During testing, in addition to traditional manual devices such as capillary tubes, heating baths, and precision thermometers, modern laboratories more widely employ fully automatic melting point apparatuses. These instruments, based on photoelectric detection and digital temperature control technologies, can automatically complete the entire process of heating, monitoring the initial and final melting of the sample, and directly record the melting curve, significantly improving the efficiency of the determination and the objectivity and accuracy of the results.