Fumed Silica "REOLOSIL™"
REOLOSIL™ is a very fine amorphous silicon dioxide produced by Tokuyama with a diameter between 5 and 50 nanometers. Its surface structure and agglomerated structure after dispersions contributes to viscosity and thixotropy in liquid resins. It is widely used as a reinforcing filler for rubber and elastomeric materials, as well as for fluidization and prevention of caking in powder materials. It can be used in a wide range of other applications thanks to its high level of purity and ultrafine particles.
|Generic names||Fumed Silica|
|Flexible containers, paper bags|
- High purity: REOLOSIL™ is manufactured using highly purified raw materials under strict process controls. Since REOLOSIL™ is high purified silica with a trace of impurities, it can be used in semiconductor materials requiring a high level of purity, including CMP slurry.
- High dispersion: REOLOSIL™ microparticles are manufactured through a vapor release reaction and form loose agglomerates. By dispersing moderately, it is possible to disperse particles smaller than the wavelength range of visible light.
- High specific surface area: The specific surface area for fumed silica is generally about 50-500 m²/g, with primary particles 5-50 nm in diameter. Because it is produced at a high temperature in a gas phase, it is an amorphous silica with no internal surface area.
- Surface chemistry: REOLOSIL™ is available in various hydrophilic grades and hydrophobic grades produced from hydrophilic silica through hydrophobic surface treatment. According to the application objectives of the powder, REOLOSIL™ can be dispersed in various dispersion media, including liquid and powder.
Key properties and effects
- Thickening and thixotropy: REOLOSIL™ provides thickening and thixotropic effects in liquid systems such as polyesters, epoxies, and urethane resins due to interaction between aggregates and the development of three-dimensional networks between REOLOSIL™ particles.
- Matting effect: REOLOSIL™ provides a deep matte surface without sacrificing transparency and tactile feel in coatings for synthetic leather, architectural structures, furniture and car interior applications.
- Reinforcement: Adding REOLOSIL™ as a filler material improves various mechanical properties of elastomers, including modulus, elongation at break, tensile strength and tear resistance. REOLOSIL™'s large specific surface area also makes it possible to achieve excellent transparency in elastomers.
- Anti-settling effects: REOLOSIL™ improves the suspension behavior in liquid systems, such as pigmented coatings or resins containing fillers.
- Anti-caking, effects for improved flow characteristics: Due to a property that makes it behave like ball bearings, REOLOSIL™ resists lumping and clogging. It can be used to improve the storage stability of powders that are especially prone to caking. REOLOSIL™ can also be used to improve flow characteristics and prevent flow problems.
- Anti-blocking effects: REOLOSIL™ is added to film resins to reduce “sticking”.It reduces close contact between film layers.
- Adsorbent: Gaseous, liquid or solid materials can be precipitated or adsorbed on the surface of REOLOSIL™. This serves as an ideal carrier or substrate for active ingredients due to its high specific surface area and inertness in the presence of all chemicals except strong alkalis and hydrofluoric acid.
- Insulation: With its very low solid state conductivity and vast spacing between particles, REOLOSIL™ provides excellent electrical and thermal insulation properties.
- Electrical charge: Hydrophobic REOLOSIL™ is used as a toner additive to stabilize electrical charge characteristics. TOKUYAMA can provide Hydrophobic REOLOSIL™ grades manufactured to custom specifications.
- Polishing: In the semiconductor manufacturing process, the planarization of silicon wafers is achieved via CMP (Chemical Mechanical Polishing) processes such as ILD, STI and metal CMP. REOLOSIL™ is used in certain CMP slurries as a polishing agent, due to high purity, sub-micron particle size and its distribution characteristics.
- Food applications: REOLOSIL™ is fluffy white powder and is used in various food applications for flowability improving, anti-settling, liquid adsorption, liquid thickening, moisture adsorption, microencapsulation, flavor masking, for example.