In order to prolong the durability of glass bead and prevent its spallation from paint after extruding by vehicles,
these beads are coated with a special coating during the production process to increase the adhesion
between glass bead and paint, so that can prolong the durability of glass bead above 20%.(It is usually used for surface treatment of Drop on glass beads).
The glass bead can be produced based on the standard of countries or areas,
such as EN1423/1424, AASHTO M247, BS6088, JIS R3301 and KS L2521 etc.