Eyemarklength Tolerances

Processing web shaped packaging materials printed eyemarklength are used for layout positioning and for controlling of sealing and cutting tools. During the manufacturing and converting process tolerances of this eyemarklength can occur. Regarding the packaging process there are differences between the tolerances demanded by the machine supplier and user and the tolerances provided by the packing material manufacturer. Furthermore there is no standard measuring procedure referring to the eyemarklength so the communication between machine manufacturer, purchasing industry and packaging material supplier is obstructed.

Aim of the project is the definition of relevant parameters of material processing with significant influence on tolerances of eyemarklength. Furthermore feasible tolerances have to be shown. With the results of the investigation it is possible to optimise the manufacturing process. The focus thereby is on aluminium- and aluminium based packaging films.

Main topics:

• Process analysis: Determination of feasible tolerances of eyemarklength by a complex investigation of the manufacturing and converting process.
• Measurement: Development of a standardised measurement procedure to enable communication between machine supplier, user and packing material manufacturer.
• Validation: Validation of the relevant process parameters with the length measuring system and the test rig for processing behavior of packaging films.
• State of art: Representation of the feasible tolerances of eyemarklength.

Within an analysis of the manufacturing and converting of three representative aluminium based films, relevant machine and material parameters of the process chain are determined, such as web tension and the profile of web tension. To validate the determined process parameters and to develop a standardised measurement procedure a length measuring system was built. With the test rig for processing behavior of packaging films the processing parameters are simulated. The achieved results are basis for a catalogue containing feasible tolerances as the state of art, which can be used to assess the process to its limits.

Aluminium- and aluminium based films are only a small part of used packaging films. Therefore a continuing research application should be worked out to investigate the tolerances of eyemarklength of polymer based packaging materials.

The project committee consist of 17 companies of packing material manufacturers, packaging machine manufacturers and users.