Pathologies of annealed glass

As we saw in the article [TBA 1 960] , outgassing can occur during the glassmaking process. These bubbles tend to form in contact with heterogeneities (furnace walls, traces of sunken material, existing bubbles, etc.). The refining and braising operations are designed to eliminate them.

For building glass, the degree of homogenization, i.e. the degree of defect acceptance, is the essential quality criterion.

For transparent glass, it is therefore essential that :

• the glass is bubble-free (at most a few fine bubbles...