It came into being all kinds of masterbatch processing equipment and production technology based on the basic theory of pigment dispersion. Mainly to solve the pigment wetting, dispersion, dispersion stability. Its goal is the pursuit of high-quality, high yield, low energy consumption, low cost. For wide range of processing generally, mainly dry production process and wet production process method.
Dry production process method is the use of additives for pigment surface treatment, the use of resin melt viscosity on shear pigment dispersion, kneading the stabilization process. The most typical is the high-speed mixer and twin-screw extruders and mixers processing process.
Wet production process rule is the use of media (solvents and water) using mechanical force ultrafine pigment dispersion and surface wetting process. The use of pigment lipophilic properties, phase inversion technique using a pigment dispersing agent into phase and stabilized. The most typical method of kneading phase inversion method and a three-roll ink.
Kneading washing method for the introduction of the Swiss company Ciba-Geigy (CIBA) wet process, the production principle: water as a medium, the pigment polyethylene wax and a surfactant in a certain speed, temperature, PH value, so that the dispersed pigment from the aqueous phase into the oil phase, and polyethylene wax coated particles formed from 0.1 to 3mm. A resin of Sciences, Beijing introduced a full set of production lines and technology and after successfully using domestic pigments. The production process uses semi ------ pigment predispersed material supply market, and achieved good economic returns. The process to produce good quality products, mainly for PP fiber spinning masterbatch, relatively high cost.
Melt shear method is to transfer high shear stress through the resin, so as to achieve the purpose of dispersion methods. Usually plastic when it close to the softening point, can have a great internal shear stress. Mixer process is the use of the above principles. Its two rotors was shaped wings, when the two rotors rotated in opposite directions, up and down and left and right roll materials can be kneaded, and the material produces a large friction. Shear the pigment aggregates is cut, pulled and dispersion. Because when kneading ram down, closed pressurized, so that the uniformity of materials. The quality of the melt shear dispersion and can produce a suitable shear force, whereas the shear size of the force is proportional to the viscosity of the polymer, the viscosity of the polymer is directly dependent on the processing temperature, so choose a suitable temperature directly affects the pigment The quality of the dispersion of its product quality and specific energy (consumed voltage / output volume) and shear rate (screw and mixing chamber minimum gap / Screw maximum line speed) related. The process is best suited for the production of carbon black masterbatch. The world's largest black masterbatch production plant such as the United States Cabot Corporation (CABOT) on the use of the process route.
