The masterbatch is a plastic colorant which is well dispersed by high proportion of pigments or additives and thermoplastic resins. The resin selected by the masterbatch has good wetting and dispersing effects on the colorant and good compatibility with the colored material. That is: pigments + carriers + additives = masterbatch, this product can be used in plastics very well.

1. Metal soap production: the size of the pigment is about 1 micron after grinding, and soap solution is added at a certain temperature to make the surface layer of each pigment particle evenly wetted by the soap solution, forming a layer of saponification liquid. When the metal salt solution is added, a layer of protective layer of metal soap (magnesium stearate) is formed by chemical reaction with the saponification layer on the surface of the pigment, which makes the surface of the pigment fine. After the pigment particles will not cause flocculation, but protect a certain degree of fineness.

2. Kneading production: mixing pigments with oily carriers, making use of the characteristics of oil-affinity of pigments, through kneading, the pigments are washed from water phase into oil phase. At the same time, the surface of the pigments is coated by an oil carrier to make the pigments disperse stably and prevent the pigments from agglomerating.

3. Ink production: As the name implies, ink paste is used in the production of black masterbatch, that is, a low molecular weight protective layer is coated on the surface of the pigment by three rolls grinding. After grinding, the fine color paste is mixed with the carrier resin, then plasticized by a two-roll plasticizer (also known as a twin-roll mill), and finally granulated by a single screw or twin-screw extruder.

4. Production by washing method: The pigment, water and dispersant are grinded by sand to make the pigment particle less than 1 micron, and the pigment is transferred into oil phase by phase transfer method, then the black masterbatch is dried. Organic solvents and corresponding solvent recovery devices are needed for phase inversion.

Different black masterbatch production methods have different advantages, which should be selected according to the characteristics of their own enterprises.