Objective: To improve pulverizing process of Canhuang tablets for promoting its quality stability. Method: Based on the preparation method of composite particles of Chinese medicine

3 kinds of ultrafine grinding process was used to prepare Canhuang tablets.The powder characteristics were investigated parallel with morphology and thermal stability evaluation by scanning electron microscopy and differential scanning calorimetry.Quality stability of Canhuang tablets with different ultrafine grinding processes were evaluated under high temperature

high humidity and strong light conditions. Result: Process 1:Coptidis Rhizoma

Indigo Naturalis

Alumen and Curcumae Radix were mixed in proportion and pulverized 20 min.Process 2:Coptidis Rhizoma and Curcumae Radix were pulverized 25 min together;Indigo Naturalis and Alumen pulverized 10 min together

then 2 kinds of powder mixed evenly.Process 3:Coptidis Rhizoma and Curcumae Radix were ultrafine grinded for 25 min together

added Indigo Naturalis continue to pulverize 10 min

then added Alumen keep on pulverizing for 5 min.The morphology and powder properties of ultrafine powders with 3 kinds of processes were obviously different

specific heat capacities of them were 262.1

242.7

295.9 J·g-1.The results of high temperature

high humidity and strong light test showed that only Canhuang tablets with process 3 was qualified with good stability. Conclusion: The ultrafine grinding process 3 under composite particles design concept can improve the powder characteristics and plasticity of tableting

and the quality stability of Canhuang tablets under this process is greatly improved.