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The first consideration is to measure the fineness, and it is even believed that as long as the fineness meets the requirements, it means that the dispersion is good. Actually, it’s not right. Once the pigment is truly dispersed, there will be significant improvements in the gloss and vividness of the paint film, not to mention the coloring power, dyeability, color vividness, and color saturation.

For carbon black, the better the dispersion, the higher the blackness and bluish tint. Compared to inorganic pigments, the better the dispersion and coverage of titanium dioxide, the higher the whiteness. It can also reduce viscosity, improve the fluidity of the color paste system, increase the loading capacity of raw materials, reduce flocculation, increase workability, and usability. It can improve the stability of the system, including storage stability, dust resistance, prevention or improvement of floating color and flower, as well as enhance its grinding efficiency, shorten grinding time, and reduce production costs. Whether the pigment is well dispersed is closely related to the dispersant.

Usually, we can use the following methods to determine whether the pigment is well dispersed. Firstly, we need to measure the fineness. If the fineness does not meet the standard, it is 100% due to poor dispersion. Secondly, we can conduct flow chart experiments, also known as Pour out. This experiment involves adding the ground color paste or paint to a resin or diluent, adjusting it to a construction viscosity or a viscosity lower than the construction viscosity. Flow coated on transparent PET film. After drying, observe its transparency or covering power, luster or physical coagulation condition, granulation and color development, etc.

Thirdly, it refers to research experiments, also known as Rub out. Add the ground paint or color paste to white paint or varnish, stir evenly, and then use a wire rod to scrape it onto black and white cardboard. After applying half dry, gently grind with your fingers on a white paper until the paint film is almost dry. Observe the color changes in the areas of the finger study and other areas without finger study.

Fourth, observe viscosity or rheological curve testing.

Generally speaking, the better the viscosity reducing effect of flocculent dispersants, the better their dispersion effect.

Fifth, it is the coating, observe its popularity, luster, fullness, and so on. At the same time, observe the color, its saturation, saturation, blackness or whiteness, coloring power, coverage or transparency, and so on.

The sixth point is to test the storage stability of his color paste. Generally speaking, the color paste is placed in an oven at 50 °~60 ° C for 15 days to observe its thermal storage stability, or in a refrigerator at minus 17 ° C and frozen for 10 days. It is to observe its cold storage stability. We will evaluate it later and compare the experiments we just conducted, such as flow coating, finger grinding, coloring power, and changes in rheological curves.