The liquid film is dispersed due to the capillary action of the liquid film, and the dispersion phenomenon caused by gravity has the greatest impact.
2. The surface tension of the liquid film on the bubble wall is reduced due to the hot spots on individual parts or the presence of defoaming additives.
3. The van der Waals force between the surface of the bubble liquid film increases the tendency of the liquid film to thin. When the liquid film is very thin, its effect is more obvious.