Summary:

K20 glass bubbles have a density of 0.2 g/cc and an isostatic crush strength of 500 psi.

Properties:

Lower viscosity, improved flow
Increased filler loading, reduced cost
VOC reduction
Chemical stability and inertness
Reduced dielectric constant
Thermal conductivity reduction
Temperature resistance
Applications:

Mining
Paints and coatings
Insulation and buoyancy
Transportation

from: palmerholland