Surface colloidal silica colloidal silica is the watery dispersoid of silicon dioxide. Used in investment casting

Surface GS-30 for investment casting

The particle size of this product is smaller than general products, so its propitious to increase compactness of the shells surface.

Designation	Standard
Appearance	Slight milky transparent to translucent
SiO2 (wt%)	29.5-32.5
Na2O (wt%)	≤0.5%
PH (20°C)	8.5-10.5
Density (20°C,g/cm3)	1.19-1.22
Viscosity (20°C,mPaS)	≤10
Particle size (nm)	8-11
Stability	Two years

Packing & Storage

Colloidal silica is packed in 25kg, 250kg or 1000kg plastic drums.

Store the colloidal silica at a temperature between 0 and 50, avoid exposure to the air, and insulate it from the sun.

Wash the empty drums as quickly as possible to avoid SiO2 crystalline deposits.

If you want to remove the deposition from empty drums, use a 10-percent NaOH solution at 50~60.

Surface colloidal silica for investment casting