Creating detailed shapes on the moulding tool surfaces with different manufacturing techniques

Environmentally friendly paperboard packaging is rapidly increasing its market share. The growth has been driven by consumers’ knowledge of ecological materials and consequent change in their consumption behaviour. Substitution of oil-based materials in the packages with sustainable alternatives, such as paperboard, has major effects on package manufacturing processes. With the advancements in digitalization and automation, the importance of identification and product safety markings has been emphasized and the integration of markings directly into packaging materials is desirable. The object of the study was to investigate manufacturing of small and detailed shapes on surface of the forming tools using these methods and how deviations on the mould surface are transferred (i.e. embossed) to the created pattern. Simultaneously, the impact of manufacturing technology on the process and parameter selection was investigated. A set of small patterned forming tools were manufactured from pre-hardened engineering and tool steel with three different manufacturing methods: precision machining, electro-erosion and laser engraving. Patterns were formed on the surfaces of the uncoated and plastic coated SBS-paperboard samples using a pressing jig designed for the purpose. Trials showed that shape of the pattern edge is essential for the preservation of the surface layer of the material. Similarly, the usable pressing force depends on the pattern edge properties. The results of the study indicate that tested simple geometry marking patterns can be created on the forming tool surfaces with commonly used manufacturing techniques.