In masterbatch production, the selection of pigments is mainly based on their heat resistance, dispersibility, brightness, light resistance and stability. High-quality pigments should have good dispersibility and bright colors, and at the same time remain stable during processing, not easy to fade or chemically react.
The particle size of the pigment is a key factor affecting its dispersion effect. Generally, pigments with small particle size, bright colors and good dispersibility are easier to disperse evenly in the resin carrier, thereby avoiding pigment aggregation and color difference.
In order to further improve the dispersion effect of the pigment, an appropriate amount of dispersant is usually added to the masterbatch formula. Dispersants can effectively reduce the interaction force between pigment particles, making it easier for pigments to disperse in the resin carrier.
The methods of pigment dispersion include dry mixing, melt shearing and liquid grinding. Among them, the dry mixing method mainly achieves the dispersion of pigments by impact grinding, while the melt shearing method uses shear stress to disperse the pigment in the melt. The liquid grinding method uses mechanical force to ultrafinely disperse the pigment and wet the surface.
In the process of pigment dispersion, parameters such as processing temperature, stirring speed and time need to be strictly controlled. Too high a temperature may cause the pigment to change color or decompose, while too low a temperature may affect the dispersion of the pigment.
During the production process of masterbatch, the dispersion, uniformity, color stability and other indicators of the pigment need to be strictly tested and evaluated. This helps to ensure that the quality and performance of the final product meet customer requirements.
During storage and transportation, masterbatch needs to be protected from adverse factors such as high temperature and high humidity to maintain its good dispersion and color stability.
