The pigment carbon black undergoes a dispersion process, and the fine particles formed by mechanical crushing form a uniform suspension with the paint, which can maintain a stable dispersion state without the action of external force. It is called a stable stage, and the dispersant plays a role at this stage. Additives. Generally speaking, the molecular weight of the dispersant is large, it can form a thicker adsorption layer. If used properly, the dispersant can not only prevent pigment precipitation, make the coating have good storage stability, but also improve the leveling property, prevent the pigment from floating and blooming, obtain a uniform color coating film, and improve the coloring power and hiding power of the pigment. , Increase the gloss of the coating film, can also reduce the viscosity of the color paste, increase the content of the pigment carbon black in the grinding color paste, improve the grinding efficiency, and achieve the effect of saving manpower and energy.
The performance and type of grinding equipment will have an important impact on the dispersion of pigment carbon black. Different products require different levels of dispersion. In many cases, the lack of plastic performance can be directly attributed to the lack of carbon black dispersion. For example, plastic products such as cable shells and optical fibers require the dispersion level of carbon black to reach a higher level. For products with high performance requirements, the full dispersion of carbon black is very important. If the dispersion level of carbon black can be maximized, the color, hue, viscosity, gloss, stability and extrusion characteristics of the product can be better met.
Commonly used decentralized equipment
The sand mill relies on the centrifugal force generated by the dispersion disk rotating at high speed to act on the dispersion medium to provide the dispersion shear force; while the ball mill relies on gravity to provide the dispersion shear force. The advantages of the sand mill are fast dispersion time, high efficiency, continuous production, and dispersion of low viscosity systems. The disadvantage of the sand mill is that it requires pre-mixing before dispersion. And ball mill cannot meet the higher requirements of carbon black powder fineness.
The main function of the carbon black three-roller mill is to overcome the cohesive force of carbon black by means of pressure and shear force, and to achieve the purpose of crushing and dispersing carbon black. In order to achieve the best dispersion level of the three-roller, the following conditions must be met: the distance between the shear surfaces (rollers) must be carefully
adjusted and stabilized, so that the pressure between the rollers reaches a constant state.
Carbon black three-roller mill produced by us can meet the requirements of producing products with high gloss, high dispersion and deep blackness