During the glass melting process of glass bottles, various salts in the powder will be decomposed at high temperature, and a large amount of released gas will be continuously removed from the melt. The melt enters the refining stage and continues to remove air bubbles. In order to accelerate the removal of bubbles, high temperature melting is generally used to reduce the viscosity of the glass liquid, or substances that reduce surface tension are added, or the pressure in the kiln is reduced to allow the bubbles to escape. But despite this, some bubbles will still remain in the glass liquid, or due to the interaction between the glass liquid and the furnace gas, the bubbles are generated and cannot be removed in time, which forms residual bubbles.
To prevent this defect, it is necessary to strictly abide by the batching and melting system, or adjust the melting temperature, change the type and amount of fining agent, or appropriately change the glass composition to reduce the viscosity and surface tension of the melt. The above are all measures that are beneficial to eliminate air bubbles in the glass liquid.