2021-10-17 Pageview:1008
MEIBOSS paint anti-mold agent is a liquid compound made of anti-mold preservative. Its advantages are the significant effect of mold pressure, small increase, long duration, safe non-toxic, excellent stability, simple use.
It can be directly poured into oil-based paint, resin, ink, pigment paste and other oil-based products, and then stirred evenly and produced according to the original processing technology.
Shrinkage, thick edges and frame phenomena can be regarded as special cases of shrinkage, that is, the shrinkage of the wet film at the corners of the substrate. Because the area of the wet film at the corners is larger than that of the flat surface and has a higher surface energy, in order to reduce the total surface energy of the system, the surface tension forces the wet film to retract from the corners to reduce the increase in surface area. To the smallest. At the same time, the higher surface tension of the wet film at the corners causes the paint with lower surface tension in the neighboring areas to flow into the corners, resulting in thicker deposits on the edges of the coating. If the thick edges have a darker color, a frame effect is formed. Therefore, shrinking edges, thick edges and mirror frame phenomena are all caused by the imbalance of the surface tension of the wet film, which prevents the shrinkage of the coating film, and improves the anti-shrinkage ability of the coating.
For the substrate, it is through surface treatment. Rice increases its critical surface tension. In addition to adjusting the coating formula, controlling the construction process and eliminating external pollution sources, an effective method is to add anti-cratering and leveling agents that can strongly reduce the surface tension of the coating to make the surface tension of the coating low. The surface tension of the substrate and the contaminants in the coating film helps the wet film to fully wet the substrate and spread evenly, and promote the surface tension of the coating film to reach the uniformity of the surface tension as soon as possible. 2. The effect of surface tension on leveling. After the coated film has gone through the two stages of wetting the substrate and spreading to form a film, it enters the leveling stage of the wet film.
Leveling refers to spreading. During the drying or curing process of the subsequent wet film, relying on the effect of the surface tension of the coating, the uneven surface of the coating film is gradually reduced to a minimum area, that is, the surface tension of the coating film tends to be uniform throughout. polypropylene wax suppliers When the wet film is just formed, because the surface area suddenly expands hundreds to thousands of times, it takes a certain time for the surface tension to be unbalanced and reach an equilibrium state. The leveling of the wet film increases with the volatilization of the solvent and the increase in viscosity. Weakened, if the wet film cannot balance the surface tension within the effective leveling time, that is, when the surface tension gradient still exists, the unleveled coating film cannot continue to be leveled to a smooth surface. Therefore, the most important thing in the leveling process is the process of uniformizing the surface tension of the wet film.
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