Aerosil Fumed Silica ( Colloidal Silicon Dioxide )

Colloidal Silicon Dioxide (Fumed silica) also known as pyrogenic silica because it is produced in a flame, consists of microscopic droplets of amorphous asilica fused into branched, chainlike, three-dimensional secondary particles which then agglomerate into tertiary particles. The resulting powder has an extremely low bulk density and high surface area. Its three-dimensional structure results in viscosity-increasing, thixotropic behavior when used as a thickener or reinforcing filler.

Scope of Application:


  • Pharmacy, all types of dosage forms
  • Food
  • Feed
  • Adhesives & Sealants
  • Coatings
  • Composites
  • Cosmetics
  • Foods
  • Inks
  • Pharmaceuticals


  • Free flow and anti-caking agent to improve powder properties
  • Improves tablet properties such as hardness and friability
  • Used as viscosity increasing agent to thicken and thixotropize liquids
  • Dessicant for moisture-sensitive actives
  • Improves distribution of active pharmaceutical ingredients
  • Used as anti-setting, thickening and anti-sagging agent
  • High purity, low humidity content
  • No influence on taste
  • Does not alter natural colour of powder formulations

Anti Settling Agent Kunsil FS-200 (Fumed Silica):

The use of Kunsil FS-200 (Fumed Silica) as an anti-settling agent for pigments and fillers in paints and coatings is the oldest application in this industry. The desired anti-settling effect is generally accompanied by an increase in viscosity and the associated yield value.

The selection of Kunsil FS-200 (Fumed Silica) with the best suspension effect is dependent on the usual factors, such as the binder system, the concentration level and other additives and especially on the particular type of pigment and filler.

Kunsil FS-200 (Fumed Silica) is not only a virtually indispensable component in zinc dust paints, but it has also been proven successful in anti-corrosive paints containing alkaline-earth metal chromates, hydrogen phosphates, lead silicates and alkaline-earth metal borates.

Matting Agent Kunsil FS-200 (Fumed Silica):

Paints are used to protect our properties from past 3,000 years. These days, we have a choice of ready-made high gloss, silk matt and matt paints. Silica-based matting agents from Kunshi Industry Company Ltd. Kunsil FS-200 (Fumed Silica) can alter the surface in such a way that the light falling on it is scattered in a defined fashion. The matting agent particles stand out from the paint, invisible to the human eye. Neither the color of the paint nor in the case of clear coatings the base is changed to any great extent.

The traditional way of reducing a coating’s gloss is to use a solid matting agent, Kunsil FS-200 (Fumed Silica). In many applications silica is preferred due to its higher efficiency. Using Kunsil FS-200 (Fumed Silica) as a matting agent utilizes particles for light scattering in the final film. In this approach the matting agent particles lead to a structured coating surface that does not reflect light directionally.

Anti Caking Agent Kunsil FS-200 (Fumed Silica):

Kunsil FS-200 (Fumed Silica) works as anti-caking agents by coating the surface of the host powder, thereby reducing interparticle interactions caused by sticky particles touching one another. Anticaking agents function either by adsorbing excess moisture, or by coating particles and making them water repellent. Some anticaking agents are soluble in water; others are soluble in alcohols or other organic solvents. Kunsil FS-200 (Fumed Silica), a common anti-caking agent which is added to table salt etc. adsorbs both water and oil. Although they are food additives, anti caking agents have other applications too. For example, anticaking agents are popularly used in non-food items like road salt, fertilizers, cosmetics, synthetic detergents, and in other such manufacturing applications.

Anti Blocking Agent Kunsil FS 200 (Fumed Silica):

Anti-blocking property is a key requirements for any type of coated items which are dried and immediately stacked or rolled up for storage or shipment. It tremendously reduces the occuring of surface defects induced by stickiness of freshly painted surface.

Anti-blocking is a non-stick situation between two surfaces. Coatings with enhanced anti-blocking ability have a good resistance to adhesion under the influence of temperature, relative humidity or even pressure fusing the surfaces together. Surface modifying additives help formulat or to improve this property by destroying the surface smoothness and by decreasing the coefficient of friction of the coating film. A well chosen wax will impact these two parameters and help you to enhance anti-blocking performance for your specific paint application. 


Properties and test methods Unit Value
Specific surface area (BET) m2/g 175 - 225
pH value in 4% dispersion 3.7 - 4.5
Loss on drying* 2 hours at 105 °C % ≤ 1.5
Tamped density* g/l approx. 50
SiO2 content based on ignited material % > 99.8