Spherical Silica

This refers to silica particles with a perfectly or nearly perfectly spherical shape. It is the most widely used term.

· Applications: Electronic packaging materials (e.g., epoxy molding compounds/EMC, underfill), high-end coatings, cosmetics, chromatographic packing materials, precision polishing, etc.
· Characteristics: The spherical shape provides excellent properties such as high fluidity, low viscosity, high packing density/filling rate, and low abrasiveness.

2. Classification by Production Method

· Fused Spherical Silica:
· Produced by melting quartz powder at high temperatures (via flame or plasma), causing it to instantly spheroidize under surface tension and then cool and solidify.
· This is the most common type of high-end product, known for its high purity and excellent sphericity.
· Precipitated Spherical Silica:
· Produced via chemical reactions in solution (e.g., reaction of sodium silicate with acid) to generate silica, with process control to form spherical particles.
· Relatively lower cost, with tunable particle size and porosity.

3. Application-Specific Terminology

· In Electronic Packaging:
· Often referred to simply as Spherical Silica or Spherical Silica Powder.
· Since it is used as a filler, it is also commonly termed Spherical Silica Filler.
· In Chromatography:
· Called Spherical Silica Gel, specifically referring to porous spherical silica with defined pore sizes and surface chemical modifications used as column packing material.
· In High-End Polishing (e.g., Semiconductor Wafers, Optical Glass):
· Called Colloidal Silica or Silica Slurry (silica polishing slurry), where the silica particles are typically spherical, monodisperse nanoparticles.

4. Differentiation from Related Products

· Spherical Silica vs. Angular/Irregular Silica:
· The key distinction lies in particle shape. Spherical silica is a specially processed, high-value-added product whose performance far exceeds that of ordinary crushed quartz powder.
· Spherical Silica vs. Silica Fume:
· Silica fume is typically amorphous, but its particles are irregular, chain-like agglomerates.
· Spherical silica emphasizes a regular spherical shape and can be either amorphous or crystalline (fused spherical silica is amorphous/glassy).