Coatings have a wide range of applications in construction, industry and decoration. In order to ensure the smooth process of coating and the superior performance of the final coating film, it is necessary to carry out coating performance testing. This test includes a number of indicators, such as covering power, usage, leveling, drying time and sanding.

1. Covering power of paint

The covering power of the coating refers to the ability of the coating film to cover the background color after the coating is evenly coated. The strength of the hiding power is affected by many factors, including refractive index, light absorption ability, crystallinity and dispersion. According to the GB/T 1727 standard, the hiding power can be measured by brushing or spraying. Coating with high hiding power can paint more surfaces under the same construction conditions, so the hiding power is an important parameter to measure the performance of the coating.

Coating construction performance test: hiding power usage level drying time and sanding

2. Coating rate

Coating rate refers to the amount of paint required to obtain a certain thickness of paint film on a unit area. It can be expressed in the form “g/m2” or “m2/L”. GB/T 1758 specifies the method of determining the amount of paint used, usually by determining the density of paint, the thickness of the brush coating film and the amount of paint used to calculate the coating rate. The theoretical coating rate can be used to calculate the amount of coating and construction cost, and is an important parameter in the process of coating construction.

3. Levelling

The leveling property of the paint refers to the ability of the wet paint film to flow to eliminate paint marks and form a smooth paint surface in a certain period of time after the paint is applied. The leveling property is related to the viscosity of the coating, surface tension and the solvent used. JB/T 3998 specifies the determination method of paint leveling, by observing the surface state of the film within a specified time to assess the leveling property. Good leveling helps to obtain a smooth and uniform film.

Coating construction performance test: hiding power usage level drying time and sanding

4. Drying time

Drying time refers to the process of gradually drying the paint from the liquid state into a solid paint film. This process usually includes three stages of surface drying, practical drying and complete drying. GB/T 1728 specifies the method for determining the drying time of paint film and putty film. The accurate measurement of drying time is helpful to arrange construction schedule reasonably and ensure coating quality.

5. Polish

Sanding refers to the degree to which the coating or putty layer is treated with sandpaper or other abrasive materials to produce a smooth, dull surface. For primer and putty, sanding is an important performance index. GB 1770 specifies the sanding test method for primer and putty film, usually by observing the surface state of the film after a specified number of sanding to assess sanding.

To sum up, coating performance testing is an important step to ensure the efficiency of the coating process and the quality of the coating film. Different performance parameters can help manufacturers and builders choose the right paint and ensure the smooth painting process. Compliance with relevant standards and test methods is key to ensuring paint performance and quality. Accurate performance testing ensures better performance and reliability of coatings in different application fields.