As we all know, the selection of various coating materials has great influence on the performance of coating. The improper selection of one ingredient may result in the failure of the entire paint formulation. Most coatings are composed of raw materials such as base material, pigment, solvent and some small amount of additives.
Therefore, in the overall composition of the coating formula arrangement, in addition to fully consider the role of each component, but also consider the compatibility and synergy between various components. After selecting the right composition, the volume concentration of the pigment must also be taken into account.
In addition, the influence of solvent on coating construction technology and coating performance, as well as the effect of solvent on controlling the fluidity, viscosity and drying time of coating, are the correct selection of coating raw materials and the overall raw material formula design must be considered.
Alkyd resin is the most used resin in coating production, its raw materials are easy to obtain, manufacture I art is simple. Alkyd resin contains a large number of ester groups, so the modification of the way is very wide. Thixotropic coatings can be prepared by modifying polyamide alkyd resin, and amino resin can be used as excellent coating materials for coil and household appliance coatings.
Color, hiding power and coloring power should be considered before pigment is added as a coating material. Color is the color that coating products need to achieve, after the overall plan of coating production is clear, the correct selection of pigments; The covering power of pigment depends on its refractive index, crystal type and particle size.
Varnish does not need pigment ratio. But paint must be added to increase color and cover. Varnish is colorless and transparent, no hiding power, so with color and hiding power of color paint in the highest proportion of paint varieties. Pigment is one of the most important paint materials.
The covering power of pigment depends not only on the amount of light scattered by the paint, but also on the absorption capacity of the light irradiated on it. Carbon black, for example, does not reflect light at all, but absorbs all the light that shines on it, so it has the strongest hiding power. In addition, the particle size of the pigment also has a direct effect on the hiding power.
The coloring power of pigments is the most easily confused concept with the covering power of pigments. The similarity of shading power and covering power is: the result of light absorption and scattering of pigment; The difference is: covering power is biased to scattering, coloring power is biased to absorption. It can be said that the stronger the pigment absorption, the higher its coloring power. The greater the coloring power of pigment, the less it can be used. Therefore, the choice of coloring power of pigment is related to whether the production cost of coating can be reduced.