The cell wall of Mycobacterium contains a large number of lipids surrounded by peptidoglycan, so Mycobacterium is generally not easy to color, the traditional staining method should be heated and prolonged staining time to promote its coloring. Once the mycolic acid in Mycobacterium combines with the dye, it is difficult to be decolorized by the acidic decolorizing solution, so it is called antacid staining.

Antacid staining solution (Kinyoun cold staining method) belongs to cold staining solution, without heating, relatively safer than antacid hot staining solution, its staining principle is that the mycobacterial acid binds to the red complex at room temperature, and after the methylene blue re-staining, mycobacteria are still in red color, while the other bacteria and the material in the background are in blue color, the staining method is darker than the improved Kinyoun cold staining method, and is more suitable for the routine antacid staining.