Waterproof Coatings The Solvent Is Evaporated And Cured To Form A Film

Waterproof Coatings The solvent is evaporated and cured to form a film

▌ gloss and gloss factors

Determination of gloss and gloss

Light to the surface of the object will be reflected in the light, the object surface of the light reflection ability called luster. Different objects on the surface of the gloss is not the same, to measure the size of the object on the light reflection capacity of the size, known as the gloss. Gloss is expressed as a percentage. The higher the gloss of the surface of the object, the stronger the ability to reflect the light, the higher the brightness. The size of the gloss is measured by an electro-optical gloss meter. According to the size of the gloss, paint can be divided into light, matt, no light and so on.

▌ factors that affect the gloss

Coat surface roughness

The surface gloss of the object is closely related to the roughness of the surface of the object. When the light is incident on the surface of the object, part of the object will be absorbed, part of the reflection and scattering will occur, there will be part of the refraction. The smaller the roughness of the surface of the object, the more light is reflected, the higher the gloss. On the contrary, if the surface of the object is uneven, the scattered light increases, resulting in reduced gloss.

Coating film forming process

After the coating is applied to the surface of the object, the film is cured by evaporation of the solvent. The coating film formation process is critical to the surface roughness and gloss of the coating. In the wet film stage, the volatilization rate of the solvent is controlled on the surface of the coating. When the volatilization rate of the components of the solvent is not very different, it is possible to obtain a high gloss surface; conversely, when the components of the solvent are in the wet film stage Of the volatile rate is not the same, it will make the polymer molecules tend to form crimp, and even precipitation, into different sizes of particles or groups, the coating surface showing rugged. In the dry film stage, the volatilization rate of the solvent is mainly controlled by the diffusion of the solvent in the whole coating film, and also affects the roughness of the coating surface. In addition, during the formation of the coating film, with the solvent evaporation, the coating will be thinned and shrink, some of the suspended particles in the coating will be rearranged in the coating surface, resulting in uneven coating surface.

The particle size and distribution of the pigment, fine material

The particle size and particle size distribution of the coating in the coating are one of the important factors affecting the gloss of the coating. When the diameter of the pigment particles is less than 0.3 m, a high gloss coating film can be obtained. The reason is that the pigment particles dispersed in the paint are made of a certain thickness of the coating film and dried, only the top layer of the pigment particles on the local protrusion, the particle diameter of less than 0.3μm pigment ions caused by the coating surface roughness Not more than 0.1μm. When the average particle diameter of the pigment is between 3-5 μm, a coating film having a better extinction effect can be obtained.