Leveling agents are widely used in various coating systems, with excellent substrate lubrication and leveling performance, good water and oil solubility, and can also prevent defects such as shrinkage and orange peel; Water based leveling agents can also improve the adhesion of water-based coatings. Leveling agent is a commonly used coating additive, and its role in coatings is irreplaceable. It can promote the formation of a flat, smooth, and uniform coating film during the drying and film-forming process of the coating.
The main function of coatings is decoration and protection. If there are flow and leveling defects, it not only affects the appearance but also damages the protective function. If shrinkage occurs, it will cause insufficient thickness of the paint film, and the formation of pinholes will lead to discontinuity of the paint film, which will reduce the protective effect of the paint film. During the construction and film-forming process of coatings, some physical and chemical changes may occur, which, along with the properties of the coating itself, will significantly affect the flow and leveling of the coating.
After coating application, new interfaces will appear, usually the liquid/solid interface between the coating and the substrate, and the liquid/gas interface between the coating and air. If the interfacial tension between the liquid/solid interface of the coating and the substrate is higher than the critical surface tension of the substrate, the coating cannot spread on the substrate, naturally resulting in leveling defects such as fish eyes and shrinkage cavities.
During the construction and film formation process of coatings, the presence of external pollutants may also cause leveling defects such as shrinkage and fish eyes. These pollutants are usually oil stains, dust, paint mist, water vapor, etc. from the air, construction tools, and substrates.
The main functions were mentioned above, and now let's talk about their uses. After coating application, there is a process of flow and drying to form a film, gradually forming a flat, smooth, and uniform coating. Whether the coating can achieve a smooth and even characteristic is called leveling. Shrinkage refers to the irregular, bowl shaped small depressions formed on the coating, which cause the coating to lose its flatness. It is often centered around a drop or small impurity, forming a circular edge around it. From the perspective of leveling, it is a special "point like" unevenness that occurs on the surface of the coating. Its shape can be divided into flat, volcano like, point like, exposed bottom like, bubble like, etc.
OneTheDefoamer for solvent based coatings
Eliminate bubbles and dents, produce a flat coating, enhance coating and scratch resistance, and avoid recoating issues The bubbles in the thick and thin coating of PU coating can be removed, which can eliminate some shrinkage and oil point defects caused by organic silicon. It prevents air carbon dioxide from remaining in the coating. It is particularly suitable for polyurethane systems and all solvent based air drying and baking coatings, solvent-free coatings, epoxy coatings, etc.
TwoTheRapid defoamer
Has a defect of increasing gloss and reducing color fading. As a special low viscosity molecular weight organic silicon compound, it can quickly remove bubbles when applied to coatings during spraying and immersion, and in certain situations, can increase coating brightness, dryness and smoothness, suppress color separation and floating, and enhance leveling and anti shrinkage functions when used in appropriate amounts.
3The Polyurethane leveling agent
Polyurethane leveling agent is generally used for waterborne coatings, especially in systems containing lotion, which has both leveling and thickening properties. It is prepared by reacting polyepoxyethane with isocyanate and then fat modifying. At present, this leveling agent has been produced by many domestic auxiliary plants, some of which are equivalent to the foreign level. With the improvement of domestic auxiliary production level and variety, people's understanding of leveling agent is gradually improved, and the consumption will increase year by year. It is also worth noting that many varieties of thickeners have a certain leveling property through fat modification or other means. Such as alkali swelling and binding thickeners, small molecular weight fat modified hydroxyethyl cellulose, etc.
4The Smooth leveling agent
It is a widely soluble polyether modified organosilicon compound that not only enhances the excellent leveling and substrate wetting properties of the coating film, but also improves the clarity, transparency, glossiness, and superior smooth touch of the coating film. It can be used for air drying, thermoplastic, thermosetting, photopolymerization, reactivity, and partially water-soluble, emulsion coating ink printing. Whether it's defoaming, foam suppression, bursting, defoaming, or smoothing agents, they all have their own advantages and uses, and their applications are becoming increasingly widespread.
