In the paint industry, grinding fineness is a crucial quality index, which is directly related to the film quality of the paint, the gloss of the paint film, the durability and the storage stability of the paint. In this paper, the concept of grinding fineness, measuring method and key role in coating production will be discussed in depth.

The concept of grinding fineness
Grinding fineness is an important measure of color and dispersion in coatings, which reflects the maximum particle size of pigment aggregates in coatings. Specifically, the grinding fineness is the reading obtained by the scraper fineness meter under specified test conditions, which indicates the depth of the groove somewhere in the scraper fineness meter, that is, the size of the solid particles in the paint that protrude above the groove depth. These solid particles are usually pigments or other dispersed solid components.

In the production of coatings, the fineness of grinding is measured not for the size of individual pigments or particle sizes, but for the size of the agglomerates that exist after the pigments are ground and dispersed during the production process. The size of these clumps directly affects the uniformity, fluidity, and quality of the final film. Therefore, accurate measurement of grinding fineness is essential to ensure paint quality.

Discussion on influencing factors and measuring methods of coating grinding fineness

Influencing factor
Grinding fineness has an important impact on the performance and quality of coatings, and the following are some of the main factors:

Film forming quality

The fineness of grinding directly affects the film forming quality of coatings. When the fineness of grinding is large, there are large particles in the paint, which may lead to the surface of the paint film is not smooth and reduce the film quality.

Gloss of the paint film

The fine particles disperse more evenly in the paint, helping to produce a nice glossy paint film. Conversely, rough grinding fineness may result in uneven luster.

durability

Grinding fineness is also related to the durability of the paint. Smaller particles help to improve the weatherability and corrosion resistance of the paint film.

Storage stability

The size of pigment agglomerates in coatings also affects storage stability. Smaller particles disperse more easily, making the paint more stable.

Discussion on influencing factors and measuring methods of coating grinding fineness

Method for measuring fineness of grinding
In the coatings industry, there are many ways to measure grinding fineness, and one of the most common methods is the scraper fineness meter method. The following is the basic principle and operating steps of the scraper fineness meter method:

It is necessary to prepare a flat test surface, usually using a special test plate or glass sheet.

Apply the coating evenly to the test surface to ensure that the coating is uniform and adequate.

Using a scraper fineness meter, scrape off the paint in a vertical direction. The Angle of the scraper and the pressure applied are key to ensure accurate measurements.

Immediately observe the scraped paint surface at an appropriate Angle. Read the scale value on the scraper fineness meter where significant particles appear on the surface of the paint. This value is usually expressed in microns (μm), a reading of grinding fineness.

Record the fineness of the grind and be sure to indicate the conditions of the test and the information of the paint sample.

Discussion on influencing factors and measuring methods of coating grinding fineness

Grinding fineness plays a key role in the coating industry, which is directly related to the quality, performance and stability of coatings. By measuring grind fineness, paint manufacturers can ensure that the product has good film quality, gloss and durability. At the same time, it also helps to improve the storage stability of the paint, ensuring that the product remains stable during long-term storage. Therefore, the measurement of grinding fineness is an integral part of all stages of paint production and is essential to ensure paint quality and market competitiveness. By accurately measuring grinding fineness, we are able to gain insight into the intrinsic properties of the paint, improve its quality and ensure that the paint performs well in a variety of applications