China is the third country that can produce float high borosilicate glass 3.3. High borosilicate 3.3 thermal shock-resistant float glass (plat borosilicate glass 3.3 in English, which can replace SCHOTT company's trademark borofloat 3.3 and Corning company's trademark pyrex 7740) is a kind of flat glass produced by float, with sodium oxide (Na2O), boron oxide (B2O3) and silicon dioxide (SiO2) as basic components. The contents of boron and silicon in this glass are relatively high, that is, boron:. 13.5%, silicon: 78? 80%。 So this kind of glass is called high borosilicate glass. Belonging to Pax glass in borosilicate glass. It is characterized by low thermal expansion coefficient and good thermal stability, chemical stability, light transmittance and electrical properties, so it has the characteristics of chemical corrosion resistance, thermal shock resistance, good mechanical properties, high service temperature and high hardness, so it is also called heat-resistant glass, thermal shock-resistant glass and high-temperature resistant glass, and it is also a special fire-resistant glass.