What is Silica?

What is Silica?

Silica (silicon dioxide: SiO₂) is a component that makes up about 75% of the earth's crust, and its presence can be found throughout the earth.
In addition to the earth's crust, silica is also found in some plants and planktonic skeletons.

■Silica in nature
  • Earth's crust
  • Plants (rice)
  • Plankton (diatoms)

Silica produced by our company

High-purity sodium silicate (Na₂O-nSiO₂), which is industrially extracted from silica abundantly present in nature, is neutralized with an acidic substance to produce silica, which is then filtered and dried to make the product.

It is called "wet-process silica" because it is produced in water.

■Wet-process silica
Wet-process-silica Wet-process-silica_sp
Our wet-process silica has a safe amorphous structure and does not cause health problems such as pneumoconiosis as crystalline silica does. Therefore, it is widely used as a raw material for various industries and as a filler, which is indispensable in our daily lives.

Types of wet-process silica

Industrial products known as "wet-process silica" are further classified according to differences in manufacturing methods. Our wet-process silica is classified into "precipitated silica" and "gel-type silica" according to differences in reaction conditions, and we manufacture and sell precipitated silica under the Nipsil tradename and gel-type silica under the NIPGEL tradename.
■Chemical reaction formula
Chemical-reaction-formula Chemical-reaction-formula

Aggregation structure of wet-process silica

Nipsil and NIPGEL growth and aggregate particles as shown in the figure below. Although the resulting particle structure differs depending on the reaction conditions, in both cases, micron-sized secondary and tertiary particles are formed by aggregation of nano-sized primary particles.
We manufacture products with various characteristics by using advanced technology to control the size (specific surface area) of primary particles, the bonding and structure of primary particles (pore structure), the size of secondary particles (aggregate particle diameter), and the state of surface modification.
Nipsil is characterized by relatively large primary particles and a soft cohesive structure, so it is used in such things as rubber-reinforcing filler and paint matting agents that require uniform dispersion.
NIPGEL, on the other hand, has relatively small primary particles with a hard cohesive structure and large pores, so it is used in such applications as anti-blocking agents for films that require high particle strength and in coating agents for ink-jet printers that require large pores.