It is now recognized as the most safe glass cup is. Some people say there are leaded glass made of glass is toxic, it is true. There are people that lead glass is more transparent, which is wrong, BPA containing more transparent plastic cup is true. Because lead with a blue silver white metal, melting point of 327.502 DEG C, the boiling point of 1740 DEG C, density 11.3437 g / cm3, the specific heat capacity of 0.13kJ/ (kg – K), soft texture, hardness 1.5, tensile strength is small.
Glass is the raw material is glass, usually the raw material is high boron silicon glass, after more than and 600 degrees of high temperature firing, it is a new type of environmental protection cup, more and more people’s favor.
Join the lead composition in the glass, can greatly improve the refractive index of the glass, looks like crystal out, called crystal glass, some of the various other ornaments, crystal glass, crystal lamp is made of glass. Lead crystal glass products relatively ordinary glass products bright color, refractive index, exquisite workmanship, feel good, looks like a crystal made of metal, gently tapping sound crisp. Lead crystal glass products compared with lead-free crystal glass products, some seem heavy.
My friends who do the insulation Cup, but also admitted that the most secure is the glass.