How to determine the fineness of paint?

Fineness refers to the size or uniformity of dispersion of particles such as pigments and extender pigments in paint or paint paste, expressed in microns (µm). The quality of paint fineness can affect the gloss, water permeability and storage stability of lacquer rattan. Due to different varieties, the required fineness of primer and topcoat is different.

At present, the most commonly used method for determining the fineness is the scraper Fineness Meter (also known as the grinding fineness plate). It is constructed as a polished flat plate made of tool alloy steel. There is a groove on the board, and there is a scale line on the bad side, which is divided into several specifications such as 0-50 microns, 0-100 microns and 0-150 microns; there is also a scraper, both edges are polished.

When in use, drop the sample into the deepest part of the ditch so that it can be filled with ditch essence and slightly redundant;

Use two hands to hold the scraper perpendicular to the plate, and pull it from the deep part of the groove to the shallow part at an appropriate speed (generally takes three seconds), so that the sample fills the groove without leaving residual paint on the plate, immediately (generally no more than Six seconds) Use a 30° angle to observe the position where the particles in the groove are evenly exposed.

Write down the reading on the scale line, which is the fineness of the sample. This method is easy to operate, easy to clean, and has a fast test speed. It is suitable for production control. However, it should be noted that the dilution of the sample should meet the requirements of the product standard to avoid errors during the test.