Glass is a cup made of glass, usually high borosilicate glass, which is fired at a high temperature of more than 600 degrees. It is a new environment-friendly tea cup. The glass is divided into double-layer glass and single-layer glass. Common glass tableware materials mainly include soda-lime glass, borosilicate glass, lead crystal glass, microcrystalline glass, tempered glass, etc. High borosilicate glass is a food-grade environmental protection material, with high temperature resistance of 150 ℃ and low temperature resistance of – 20 ℃. It can withstand very high instantaneous temperature difference. It will not crack if it is filled with ice water and then directly filled with boiling water. Wear-resistant, acid-resistant and alkali-resistant. It can be used to hold various kinds of tea, fruit juice, carbonated drinks, etc. The crystal glass water cup is a high-end product in glass. Because it contains many metal elements, its refractivity and transparency are very close to natural crystal, so it is called crystal glass. There are two kinds of crystal glass, lead crystal glass and lead-free crystal glass. Lead crystal glass is not recommended for consumption, especially for drinking acidic drinks in common cups. Lead will be dissolved in acidic liquid, and long-term consumption will cause lead poisoning. Lead-free crystal is lead-free and harmless to the body.
High borosilicate glass is a kind of glass with sodium oxide (Na2O), boron oxide (B2O3) and silicon dioxide (SIO2) as the basic components. The content of borosilicate in the glass composition is relatively high, namely, boron: 12.5~13.5%, silicon: 78~80%, so this kind of glass is called high borosilicate glass. The high borosilicate glass is safe, stable, non-toxic, and has a very low coefficient of thermal expansion, which is only about one third of that of ordinary glass. Therefore, it can withstand sudden temperature difference. For example, the glass will not break when taken out of the refrigerator to pour hot water. It is a good glass cup material commonly used in life.