The hollow glass microspheres are small, hollow spherical powders having a density between 0.1 g/cm3 and 0.5 g/cm3, and the particle size can be selected between 1 and 500 microns as needed. It has the advantages of light weight, large volume, low thermal conductivity, high compressive strength, insulation, self-lubrication, sound insulation, non-absorption, fire resistance, corrosion resistance, radiation resistance, non-toxicity, and dispersibility, fluidity and stability. Hollow glass beads can be directly filled into most types of thermoset, thermoplastic resin products. When applied in a powder coating, the hollow glass microspheres can function as follows.
 (1) Insulation, insulation, and low water absorption. The interior of the hollow glass microspheres is vacuum or a thin gas. It has a density and thermal conductivity difference with the epoxy resin, so it has the property of heat insulation and is an excellent filler for high temperature powder coatings. The thermal insulation properties of the beads also reduce the thermal shock caused by the powder coating being subjected to rapid heat and rapid cooling. The extremely low water absorption allows the powder coating to be stored for long periods of time.
(2) It can improve the physical and mechanical properties of the powder coating. Hollow glass microbead fillers increase the hardness and stiffness of powder coatings. However, the impact resistance fell, and the amount of decline was related to the surface treatment of hollow glass beads. If the correct coupling agent is used for pretreatment, the impact on the impact resistance of the material can be reduced.
(3) The oil absorption rate is low. The hollow glass microbeads have a lower oil absorption than the conventional filler material calcium carbonate. Different types of hollow glass microbeads have an oil absorption rate of between 7 mg and 50 mg per 100 g, and the oil absorption rate per 100 g of light calcium carbonate is as high as 120 mg to 130 mg, and that of heavy calcium carbonate is as high as 50 mg to 60 mg. This low oil absorption filler material increases the filling amount in a phase in the production experience and reduces the overall cost.