FIELDS OF APPLICATION
Pyrogenic silica "Orisil" is used in many different applications:
Paints and coatings
Orisil fumed silica functions as a stabilizer, prevents settling of pigments and acts an anti-sedimentation additive. Silica improves thixotropy, rheological properties of paintwork materials without staining transparent varnishes. In liquid compositions containing solid particles, such as pigmented varnishes, paints and enamels, the addition of Orisil facilitates pigment dispersion and prevents solid phase sedimentation, stabilizing the system. It also has the effect of significantly strengthening the coating film, adhesion to the applied surface, slowing down the rate of aging of the coating as well as the burn-out of materials under the clear coat.
In powder coatings, Orisil promotes free flow, prevents caking and modifies electrostatic effect. Orisil can also be used to control gloss in some coating applications, such as urethane satin finishes.
Inks
In industrial inks Orisil fumed silica is primarily used as a thickener. In offset printing, hydrophilic Orisil speeds up ink drying, reduces the risk of smearing and improves image definition. Treated Orisil reduces water absorption of the ink, inhibits foaming, increases color intensity preserving the luster of the surface. In engraving, flexography and silkscreen printing, Orisil is used to regulate viscosity and prevent pigment deposition.
Orisil can also be used to control ink flow in printers and copiers.
Sealants and adhesives
Besides the thickening effect, Orisil fumed silica provides necessary mechanical strength of sealant after curing.
During production of adhesives, a small amount of Orisil slows down sedimentation, increases viscosity, reduces curing time and the ability of the adhesive to be drawn into threads.
In cases where particularly high moisture repellency is required, a treated Orisil fumed silica may be used.
PVC plastisols
Orisil fumed silica is used as a filler in PVC plastisols. A small amount of the product significantly increases the viscosity of the plastisols. In addition, the presence of Orisil in plastisols greatly increases adhesion to metal surfaces. This is important for industrial applications where plastisols are spray applied.
Battery acids
The plates of modern lead-acid batteries are contained in the acidic electrolyte, which when thickened with Orisil fumed silica, becomes gel-like. This significantly reduces shedding of the plates and prevents leaking. Orisil does not react with acid and does not affect the properties of the electrolyte.
Thermal insulation
Due to microscopic particle size and large spacing between the particles Orisil fumed silica has excellent thermo-isolating properties. The thermal stability of Orisil at 1200 ºC makes it possible to use it in the insulation of furnaces, aircraft turbines, etc. As an effective thermal insulating material Orisil is used in refrigeration units of air separation plants, as well as for thermal insulation of liquefied gas storage tanks at sub-zero temperature.
Orisil is a key component in production of VIP (vacuum insulation panel) based on pyrogenic silica.
The mixture consists of micronized cells, the distance between which is less than the free path of air molecules. Accordingly, VIP panels are not affected by thermal processes associated with the collision of molecules and heat dissipation.
Powders and bulk materials
Orisil fumed silica is used as an anti-caking agent during fertilizer production because it prevents agglomeration of particles. Since Orisil is an inert product, it does not affect the chemical properties of powders. It enhances the fluidity of powders, prevents sticking in molds, and is used in powder based fire extinguishers.
Orisil also prevents powdered sugar, flavored salt and spices from sticking together when making potato chips.
It regulates dry toner flowability in printer cartridges.
Сosmetics and personal care products
Orisil fumed silica is used in cosmetics and personal care products because of its specific properties. In coloring products, Orisil controls viscosity and prevents agglomeration of pigments. In powders, Orisil increases fluidity. In nail polishes, Orisil influences pigment distribution, reduces sedimentation and controls rheology. Orisil can also be used in lipsticks, antiperspirants, toothpastes, haircare products and other products.
Food industry
Orisil fumed silica is used in the food industry as an anti-caking agent for bulk products, it promotes free flowing and ensures stable storage.
Orisil adsorbs liquids and forms dry powders that can be easily mixed with other solids. At high concentrations, pyrogenic silica can act as a flavor masking agent, facilitating the preparation of fortified foods.
Orisil is also an effective thickener, emulsifier and gelling agent. It prevents sedimentation and is able to retain heavier elements in the system.
Pharmaceutical industry
Orisil fumed silica provides pastes and ointments with the desired consistency and prevents the components from separating. Small additives stabilize emulsions and lotions. Powder products (antiseptic and cosmetic powders) are well distributed and applied to the skin due to Orisil additives.
Orisil is used as an auxiliary substance for tabletting and drugging medications.
The use of Orisil in medicine is important because all substances previously absorbed on its surface, such as medications, are gradually desorbed in the aqueous environment of the human body, providing prolonged action and increased efficacy of medications.