The road marking glass beads are a kind of fine glass beads formed by melting glass sand, which served as a raw material after high temperature melting. This glass bead is a colorless, transparent and bright sphere under the observe with the microscope, and there are no obvious bubbles or impurities. The road marking glass beads used in road markings have a refractive index between 1.50-1.65 and a particle size generally between 70 microns and 800 microns, so they can be also called glass beads for road reflection. At present, the main processes for producing road marking glass beads in China are flame floating method and electrothermal melting method. The glass beads are a new type of material with wide application and special performance developed in recent years.It is made by boron salt raw material through high-tech processing which has the advantages of light weight, low thermal conductivity, high strength, good chemical stability, and so on. Its surface has been specially treated to have lipophilic and hydrophobic properties, and it is very easy to disperse in organic material systems.
The road marking glass beads can be divided into surface-spreading glass beads and pre-mixed glass beads according to different usage conditions. The surface spreading glass beads means spread on the surface of the wet marking paint after the paint draws the marking on the pavement. The pre-mixed glass beads are glass beads mixed uniformly in the paint before the marking of the road marking paint. The road marking glass beads are mainly used in normal temperature and hot melt road marking coatings. The pre-mixed glass beads can guarantee the long-term reflection within the lifespan, while spreading glass beads on the surface can play a timely reflection effect.
As a reflective material in road markings, the road marking glass beads can greatly improve the reflective performance of pavement marking paints, thereby improving the safety of driving at night, which has been determined by the transportation departments of various countries. When the car is driving at night, the lights illuminating the road markings with glass beads can reflect the light of the lights back in parallel, so that the driver can clearly see the direction of travel and improve the safety of driving at night. At present, the reflective glass beads have become an indispensable reflective material in road safety products.