Silica-gel Characteristics

Controlled Porosity

Silica Gel CharacteristicsFuji Silysia Chemical products have a range of pore volume (PV) and pore diameters (PD). The pore volume plays a significant factor for each type of application that can affect performance in matting, anti-block, clarity, receptivity, dispersion, absorption and various other properties. The pore volume is associated with Oil Absorption and Surface Area. This requires vigorous quality control during the manufacturing process.

PV (ml/g) 1.80 1.60 1.25 0.80 0.44
PD (nm) 24 21 17 7.0 2.5


Silica-gel has a very high purity at 99.7% SiO2. This makes it a very safe and inert product used across the board for food and pharmaceutical applications. The low impurity content will not affect formulations in coatings and cause adverse reactions. All Fuji Silysia untreated grades qualify for FDA certification.

SiO2 99.7%
Na2O 0.06%
Al2O3 < 0.01%
Fe2O3 < 0.01%
Ca O 0.07%
Pb below detection limit
Cd below detection limit
Hg below detection limit
Cr6+ below detection limit

Particle Size Distribution

Narrow particle size distribution is the hallmark of Fuji Silysia’s technical engineering. Obtaining more particles of a given average particle size increases consistency and reduces unexpected errors, deformation and lack of performance. FSC particle control is steady from each lot manufactured to maintain high product reliability.

Silica Size Chart

Surface Treatment & Morphology

SilanolThe silica surface is covered by hydroxyl groups (-OH) called silanol (Si-OH). To improve wetting in solvent or low polar systems, various chemical treatments are applied to mask this functional group. These treatments can also moderate hard settling, mar and burnish resistance and UV performance. Other engineering modifications are performed for chromatography, corrosion resistance and catalyst support.

Through different manufacturing techniques, silica-gel can be formed into spheres. While most FSC products are granular, spherical products are engineered in particle sizes ranging from micron to millimeter.