Glass microsphere toys for sound insulation and heat insulation, made of 3-4mm transparent glass microspheres and reflective material for road surface.

Hollow glass microspheres are specially processed glass microspheres. Their main feature is that they have a lower density and poorer thermal conductivity compared to regular glass microspheres. They were developed in the 1950s and 1960s as a micrometer-sized lightweight material. Their main component is borosilicate, with a typical particle size ranging from 10 to 250 μm and a wall thickness of 1 to 2 μm. Hollow glass microspheres possess the characteristics of high compressive strength, high melting point, high resistivity, low thermal conductivity coefficient, and low thermal contraction coefficient.