Carbon black, which is difficult to disperse, also puzzles our black masterbatch manufacturer, because the dispersion of high-load black masterbatch produced by single or double screw extruder is very poor. When the end users mix or die cast these black masterbatch, its performance is only slightly better than that of carbon black, but the effect is also unsatisfactory. In order to achieve a stable high dispersion, it is necessary to use a high-level shear mixer to mix carbon black, such as a mixture of FCM or BANBURY. With sufficient strength, these mixers can completely mix carbon black and base resin together, and the type of carbon black used also affects the dispersion. The smaller the carbon black particles are, the more difficult the dispersion is. The second factor that determines the quality of black masterbatch is covering power, which is especially important for color masterbatch used in waste or recycled polymer. In these cases, the role of black is to cover other colors in waste. The coloring ability of large particle carbon black is poor, and it is not easy to cover all other colors in the lower layer. As a result, the final product only gets the deviated color. In the melting process, the ability to correctly select carbon black with high coloring ability to cover the existing color is the so-called covering power
