GLASS MICROSPHERE FOR RETROREFLECTIVE COATINGS Russian patent published in 2019 - IPC C03C12/02 C03C3/87 

FIELD: chemistry.

SUBSTANCE: invention relates to glass microspheres which can be used in road surface marking and in fabrication of retroreflective devices. Glass microsphere is made from transparent colorless sodium-calcium-silicate glass and is formed at a rate which prevents the appearance of a crystalline phase. Glass sphere contains the following components, wt. %: 54.0–70.0 SiO₂, 17.0–30.0 CaO, 7.0–16.0 Na₂O and/or K₂O, 0–5.0 MgO, 0–5.0 Al₂O₃, not more than 0.1 Fe₂O₃ and has a refraction index of more than 1.53, preferably of not less than 1.539.

EFFECT: technical result consists in improvement of efficiency of reflection of glass microspheres by increasing the refraction index of glass, increasing the coefficient of optical transmission of glass and increasing the fraction of spherical glass microspheres.

3 cl, 2 tbl