Types of silicone softeners:
micro silicone, very soft; They provide long-lasting softness to the fabric. It has no negative effect on color stability. Their resistance to washing and dry cleaning is good.
Macro silicones are used as silicone softeners for impregnation processes. They provide smoothness and shine of the surface. They give the fabric a soft and slippery touch. They increase the depth of color in dark colors and provide ease of sewing.
Nano silicones are permanent, hydrophilic and jet resistant silicone softeners for all textile fibers. They have excellent tensile properties and resistance to circulation. They have high resistance to yellowing. Since their washing resistance is good, they last a long time. Compared to micro-silicones, they have a wide range of pH resistance and high resistance to temperature and electrolytes.
anti-foam
Chemical foam control agents are called antifoams or defoamers. Antifoams prevent or delay the formation of foam. Defoamers are surfactants that break down foam after it has formed. The function of degassing is to facilitate the rapid rise of microfoams to the surface.
The purpose of foam removal is to reduce the surface tension of the environment. Defoamers must have a low surface tension in order to reduce the surface tension of the environment and remove the foam.
For this reason, they generally show the following three characteristics.
Solution Not in the environment
Positive entry coefficient
Positive diffusion coefficient
This means that for a substance to be considered antifoam, both its entry coefficient and diffusion coefficient must be positive Entry coefficient and diffusion coefficient are factors that vary depending on the surface tension of the foaming medium - interface - defoamer. By calculating the values of these two factors, it is possible to determine the reliability of a material as a defoamer.
Defoamers must meet all expectations incrementally and overcome the mechanism of foam stabilization. To migrate to the air interface, it must have a limited solubility in the coating.
The cutting mechanism of defoamers (especially in aqueous systems) can be explained as the addition of well-dispersed hydrophobic particles. The defoamer acts as a carrier medium by transferring the particles into the foam layer. On the one hand, hydrophobic particles act as foreign particles in hydrophilic liquid lamellae and thus help to reduce adhesion forces, and on the other hand, by trapping active substances on their surfaces, they reduce foam stabilization. >
The stability of the foam is disturbed by the removal of free active substances from the bubble wall. Antifoam products actually do this by absorbing the hydrophobic ends of the active ingredient into their hydrophobic surface. As a result of reducing the adhesion forces, the surface tension decreases and the foam explodes on the coating surface. The surface tension of the defoamer should be lower than the surface tension of the solution. In the solution, the solubility of the defoamer should be low. The defoamer should be easily dispersed in the solution.
It should not react with the defoamer solution.
It should have a high diffusion coefficient.
It should have a high penetration coefficient. which is harmful to the final product.
Types of antifoams
Defoamers based on mineral oil
Defoamers based on mineral oil are used more in water-based systems than in solvent-based systems. Although this type of defoamer is mostly used for matte and medium gloss emulsion paints, it can be safely used in high-quality colors as well.
Defoamers based on mineral oil are generally mineral oils in the carrier part and are composed of hydrophobic active ingredients, emulsifiers and other additives. Defoamers based on mineral oil
Defoamers based on mineral oil in systems Water-based is more commonly used than solvent-based systems. Although this type of defoamer is mostly used for matte and medium gloss emulsion paints, it can be safely used in high-quality colors as well. Mineral oil-based defoamers are generally oils. They are mineral in the carrier part and consist of hydrophobic active materials, emulsifiers and other additives. Defoamer based on mineral oil
Defoamer based on mineral oil is used in water-based systems more than solvent-based systems. to be Although this type of defoamer is mostly used for matte and medium gloss emulsion paints, it can be safely used in high-quality colors as well. Mineral oil-based defoamers are generally oils. They are mineral in the carrier part and consist of hydrophobic active ingredients, emulsifiers and other additives.
Silicone-containing antifoams are more resistant defoamers. However, their use in coatings can lead to severe surface defects such as pitting. Better compatibility is achieved by modifying the hydrophobic polyether with polysiloxanes. Also, this type of defoamer does not tend to negatively affect gloss. If the product containing silicone is chosen correctly, added in the right amount and in the right place, the adverse effects will disappear.
Defoamers are prone to breakdown because they contain hydrophobic silica. For this reason, most defoamers must be shaken before use. They are mostly packaged in 50kg drums with easy shaking capability.
Freezing is usually not a problem, but if it is, the product should be allowed to return to room temperature and shaken.