What is silica sol? If you were to get a direct introduction like this, would you be confused? Silica sol is a nanomaterial with excellent performance. It is a colloidal solution formed by uniform dispersion of amorphous silica particles in water or organic solvents. It is an inorganic polymer material with extremely wide applications.
It seems that I have some concepts in my mind, but I still feel a little confused. Don't worry, put silica sol aside first, and look at the close connection between silica sol and our lives. After reading it, you will understand what silica sol can do.
Electronic industry
For more than 70 years, the electronics industry has developed rapidly, and the demand for substrate materials for optoelectronic products has increased day by day. The substrate requires good flatness. Chemical mechanical polishing technology (CMP) is a combination of mechanical grinding and chemical etching. It is used to achieve atomic-level ultra-smooth surfaces on various materials. It is also recognized as the only technology that can achieve global planarization.
This process has been widely used in the fine polishing and rough polishing of silicon wafers, as well as the processing of semiconductor devices, polycrystalline modules, flat panel displays, optical camera tubes, micro-motor systems, etc. Especially in large-scale integrated circuits, it is used for flattening of multilayered films.
Polishing liquid plays an important role in CMP, and the most widely used one is silica sol. The polishing liquid composed of submicron or nano-scale SiO2 abrasives and chemical solutions flows between the workpiece and the polishing pad and produces a chemical reaction. The chemical reactants formed on the surface of the workpiece are removed by the mechanical action of the SiO2 abrasives, that is, ultra-precision surface processing is achieved in the alternating process of chemical film formation and mechanical film removal.
Textile industry
After using silica sol in the dyeing process of fabrics, it can greatly enhance the adhesion between pigments and fabrics, increase uniformity and fastness, and effectively avoid the agglomeration of pigments.
If synthetic wool oil is added to silica sol for the manufacturing process of fibers, it can not only greatly improve production efficiency and obtain high-count fiber products, but also enhance and increase the cohesion and tension resistance between fibers. Similarly, if the resin is treated with silica sol, the washing resistance and wear resistance of the resin can be enhanced, effectively preventing the sliding of synthetic fibers.
Coatings
Since the particles of silica sol are relatively fine, the silicon oxide formed when it precipitates is highly active, and the film-forming effect is also good after forming new silicate inorganic polymer compounds with certain metal oxides and inorganic salts; when the fine particles enter the substrate through super strong penetration force and generate CaCO3 with the alkaline substances in it, a coating layer with strong adhesion is formed.
Refractory materials
Sol can be used as a binder to sinter industrial ceramic devices, such as refractory bricks and high-temperature porcelain tubes. It can be used for aluminum silicate fiber firing insulation equipment, such as capillary tubes. It can also be made into coatings with short fibers to insulate tall furnace bodies. Compared with other binders, the equipment produced has greatly improved and improved in many aspects such as durability, high temperature resistance, and insulation.
In the preparation process of amorphous refractory materials, silica sol is usually used as a binder, mainly because it does not contain low-melting point oxides, which will not cause the performance of refractory materials to deteriorate at high temperatures.
Papermaking industry
After being mixed with monostearate, silica sol can be used on glassine and plastic film to effectively prevent stickiness in summer. In order to improve the strength, anti-slip and moisture resistance of paper products and avoid sliding between paper layers during transportation, the surface of kraft paper and corrugated paper is usually treated with silica sol.
Similarly, in order to make the color of non-gray carbon paper more vivid, silica sol is usually used to replace talcum powder, clay and other powder coatings in its production process.
After the pre-coating of photosensitive paper and offset paper is treated with a mixture of silica sol and photosensitive liquid, the paper surface becomes smoother, the image of the photosensitive paper becomes clearer, and its exposure range is increased.
Other aspects
In electrostatic flocking technology, acidic silica sol is the main component of the flock treatment agent. The silanol group formed on the fiber surface can effectively improve the charging of the flocking hair and solve the problem of hydrophilicity of the fiber.
As an additive, silica sol is also widely used in the production of medicines and toothpaste, and can also be used as a catalyst carrier, etc.
Since silica sol has a large surface area and is dispersed in the solution in the form of spherical particles, it has good optical density and printing clarity in the inkjet coating, can quickly dry the ink, and has good dispersibility, which reduces the use of adhesives in the base material, saves costs, and reduces processes.