Also known as alkali-free glass, it is a borosilicate glass. At present, it is the glass fiber with the most widely used glass component. It has good electrical insulation and mechanical properties. It is widely used in the production of glass fiber for electrical insulation. It is also widely used in the production of fiberglass for glass reinforced plastic. Its disadvantage is that it is easy to be Inorganic acid is eroded and therefore not suitable for use in an acidic environment.