Glass beads
 
Glass beads are made by firing glass sand. Glass beads can be divided into glass beads (glass beads are a kind of glass beads, which refer to solid spheres with a particle size of less than 1mm) and glass beads. By use
 
It is divided into glass beads for reflection, sand beads for pill, glass beads for grinding, glass beads for filling. Among them
 
Light glass beads can be divided into safety protection reflective glass beads and screen glass beads; According to the refractive index, it can be divided into ordinary refractive index and high refractive index glass beads. The general refractive index is 1.5-1.64, and the high refractive index is generally 18-22. If the glass beads with refractive index of 1.93 are most suitable for reflection, this refractive index can perfectly refract back to parallel light, so the higher the refractive index, the better the reflection effect. According to the shape, it can be divided into regular glass beads and irregular glass beads. According to color, it can also be divided into colored glass beads and colorless transparent glass beads. Let's talk about the glass beads for road reflection.
 
Reflective glass beads for roads
 
Road reflective glass bead is a kind of small glass bead formed by melting glass sand (waste glass) at high temperature. It is spherical, colorless and transparent under the microscope, with a refractive index of 1.50-164 and a diameter of 75 microns to 1400 microns. It is also called reflective glass bead. At present, the main processes for producing road reflective glass beads in China are flame floating method and electrothermal melting method.
 
As a reflective material in road marking (paint), road reflective glass beads can improve the retroreflective performance of road marking paint and improve the safety of driving at night, which has been determined by the transportation departments of various countries. When the vehicle is driving at night, the lamp shines on the road sign line with glass beads, which can make the light of the lamp reflect back in parallel, so that the driver can see the forward direction and improve the safety of driving at night. Now, reflective glass beads have become irreplaceable reflective materials in road safety products.
 
Rate. The performance of glass beads after coating treatment is more superior. It has better reflective function in wet environment with frequent rain and fog
 
technical parameter
 
Appearance: colorless transparent sphere, smooth and round, without obvious bubbles or impurities.
 
Rounding index: rounding index ≥ 80%, density: 2.4-2.6g/cm3, refractive index: Nd ≥ 1.50
 
Composition: sodium calcium glass, SiO2 content > 70%
 
Some national executive standards:
 
Chinese standard GB / t24722 -- 2009 No. 1, 2, 3;
 
Korean standard ksl2521 No. 1 and 2;
 
British standard bs6088 class A and B;
 
American Standard AASHTO M247 type 1 and type2;
 
European standard en1423and en1424;
 
Turkish standard TS en1423:
 
New Zealand Standard nzs2009:2002: