Leonhard Kurz, a coating manufacturer, has developed a process for combining IMD (In-Mold Decoration) with PUR technology. In this process called IMD PUR, plastic parts are decorated during injection molding by in-mold decoration and then overflooded with PUR (polyurethane) within the same clamping unit. This produces sophisticated designs under a clear, glossy surface. PUR layer thickness varies between 0.3 and 15 millimeters and can give a marked depth effect. Apart from the glossy finish, the PUR coating also provides surface protection. The decoration remains intact when subjected to scratches or stone impact, and the PUR topcoat is self-healing when scratched.
Technological advances in IMD coating and mold technology
The production and PUR flooding of injection-molded parts in a single machine pass is a known process. The novelty, however, is in combining this with the IMD process. Kurz has developed IMD coatings that adhere perfectly to the PUR topcoat. The mold manufacturer, Schöfer, a member of the Kurz Group, with its specialist experience in mold-making, complements Kurz’s comprehensive know-how in thin-layer and process technology. The combined effort has made it possible to perform injection molding, IMD coating and PUR coating in a single clamping unit. Furthermore, the tailored formulations of the IMD and PUR layers, as well as process-optimized molds, are said to ensure reduced cycle times.
The IMD PUR process combines the advantages of the IMD and PUR technologies. Plastic decoration by IMD PUR results in high surface quality, depth effect and glossy appearance of PUR coatings. Simultaneously, IMD PUR offers design freedom to perform design changeovers quickly and efficiently.
Kurz will be presenting the new IMD PUR process at K 2019. At the Kurz stand A19 in Hall 5, Engel duo 2460/900 injection molding machine will produce plastic parts decorated by IMD PUR. The production and decoration of components with complex geometries will be demonstrated by an automotive front panel.