Borosilicate glass is obtained by substituting boron oxide for a part of the alkali metal oxide in ordinary glass. That is, high boron low silicon borosilicate glass containing no alkali metal oxide. Glass and bismuth glass belong to the alkali-containing borosilicate glass system. Heavy glass is an alkali-free borosilicate glass system. The content of B2O5 is gradually increased in borosilicate glass, and this phenomenon is called boron anomaly. It has good chemical stability and is therefore widely used in the chemical industry.