The GB/T 1725-1979 standard specifies a method for the determination of Coating solids by volume, which is suitable for evaluating the proportion of solids remaining in Coating after heating. This method uses Glass culture dish or watchglass to determine the solid residue of the sample by stoving it at a specific temperature. The standard describes the instrumentation, operation steps and calculation methods in detail, ensuring the accuracy and Repeatability of the measurement. This method is of great significance for Coating production and quality control, helping to determine the actual solids by volume of Coating.