Extrusion International 4-2022

46 Extrusion International 4/2022 SHEET EXTRUSION – CASE STUDY Multi-Touch Roll Stack is Good for our Feet The sustainable plastic floor boards made of CERAMIN by CLASSEN for healthy living are recently being produced on a complete extrusion line with aMulti-Touch roll stack frombattenfeld-cincinnati Germany GmbH. CLASSEN, based in Kaisersesch, Germany, is the inventor andmanufacturer of these innovative, PVC-free floor coverings with the “Blue Angel” seal of quality. C ERAMIN is produced from polypropylene as base ma- terial. It is pollutant-free, 100 per cent recyclable and produced with recycled materials. The sturdy, durable floor coverings based on CERAMIN offer all the advantages of plastic flooring for private residences as well as for pub - lic and industrial buildings. The floors are dimensionally stable, abrasion- and water-proof, warm to the touch and resistant to UV light. Conventional plastic floors based on soft PVC have the disadvantage of poor recyclability and are subject to criti- cism due to their pollutive ingredi-ents such as chlorine, stabilizers, phthalates and other plasticizers. This is why the CLASSEN Group has developed CERAMIN as a material for the car-rier boards of PVC-free floor coverings. In detail, CERAMIN boards consist to 60% of a natural mineral filler material, to 39% of polymers based on polypropylene, and to 1% of environmentally friendly and health-compatible additives. The carrier boards in plastic floors from CLASSEN are covered with a protective undercoat as well as a primer and decorative layer with a soft-touch surface finish tomake human feet feel comfortable. In the production of themain component, that is, the 2-to- 5-mm-thick board, it is of course vital that the board is abso- lutely even, has a clean, ripple-free surface and complieswith extremely narrow strength toleranc-es. This is important for further processing as well as for its later use as floor cover - ing. In the battenfeld-cincinnati line, the impeccable quality standard of the CERAMIN board with high filler content is primarily due to the Multi-Touch roll stack. Due to continu- ous contact between the board and the rolls, this device en- sures perfect conditions for calibration and cooling. The two lines now installed at CLASSEN are equipped with two twin screw extruders from Leistritz Extrusion GmbH, based in Nuremberg/Germany, which are connected to the dosing unit and ensure perfect homogenizing of up to 8 t of melt per hour. Downstream, these are connected to an auto-matic flat-sheet die, through which the melt film pro - ceeds into the 2.6 m-wide Multi-Touch roll stack. Here, pre- calibration takes place in a two-roll stack, before the board passes through several more rolls for recalibration. In this way, the surface of the board is continuously in contact with the roll surfaces over a considerable period of time, with the result of perfect di-mensional stability and excellent visual attributes. The haul-off is followed by a size cutter. The com- plete line is controlled by BCtouch UX, which is integrated in the customer’s PDA system. In a second processing step, the boards are laminated as described above with the various layers of film and thus provided with a decoration chosen from a large, diversi- fied range of patterns. battenfeld-cincinnati Germany GmbH Bad Oeynhausen, Germany www.battenfeld-cincinnati.com CLASSEN www.classengroup.com