Compounding: Quick-Color-Change Lab Twin

KraussMaffei demonstrated the quick-color-change capabilities of its ZE 28 BluePower laboratory twin-screw compounding extruder at K 2019, running liquid color.

Use of liquid color is a growing among masterbatch compounders because it gives them greater flexibility to respond to market requirements, says KraussMaffei. The machine builder explains that because liquid colors are metered directly in the extruder, there is no need for the  intermediate step of manufacturing a monoconcentrate, making the process especially economical and suitable even for very small volumes and special colors. Even converting from dark to light is possible without any problem thanks to the self-cleaning effect of the twin-screw extruder, says KraussMaffei. Throughout the show, KraussMaffei ran nine different colors with a talc-filled PP masterbatch, making changes at the touch of a button.

The line also was equipped with automatic inline melt  monitoring. The spectral-photometric inline system uses high-resolution glass fiber sensors to measure the light reflected by the melt during the process, then compares this with the defined target value to detect even the very slightest difference in brightness or color in real time. Benefits include no need for sampling, no loss of material and real-time results.