Sumitomo (SHI) Demag Plastics Machinery GmbH

Systec SP and IML/IMD injection moulding – Sumitomo (SHI) Demag presents a new packaging machine and a production cell for multitouch displays

An IML-decorated bucket, content 1.2 l, very economically manufactured using the new Systec SP 280 packaging machine.

At this year’s K trade fair, held in Dusseldorf on 16 - 22 October, Sumitomo (SHI) Demag Plastics Machinery will be presenting two technical innovations on Stand D22 in Hall 15. These are Systec SP, a packaging machine based on the Systec platform that has proved itself over many years, and a fully-automated IML/IMD production cell, in which for the first time, a 5” multitouch display is created by injection moulding in a single step.

High flexibility through a freely combinable range of features, available from the comprehensively equipped basic version to the complete finishing cell; these are features of the Systec machine platform that is trusted all over the world by processors from a wide range of industries. At the K in Dusseldorf, Sumitomo (SHI) Demag will now for the first time demonstrate to the international professional audience two new developments based on this platform under production conditions.

Systec SP – developed for economic packaging injection moulding

With the Systec SP 280 (clamping force 2,800 kN), Sumitomo (SHI) Demag is presenting at K a new type of machine, tailored to the packaging injection moulding. The “SP”, as an abbreviation for “Speed Performance” in the machine name, documents that the demands for increased performance and speed for packaging injection moulding are covered by a hybrid drive system and specific feature modules. Combined with the robust Systec platform, this, at the same time, leads to a very good price-performance ratio. The application area for the Systec SP is the process stable, commercial mass production of packaging articles, such as latches, lids, buckets, stacking boxes, etc. An example of the performance will be demonstrated on the exhibition stand in Dusseldorf with the production of IML-decorated PP buckets (content 1.2 l). With the double mould used for this and an injected weight of 84 g, the cycle time is only 5.3 s. Parallel removal of the decorated bucket and the insertion of the IML label into the mould for the next cycle are performed by high-speed linear handling, developed by Sepro Robotique in collaboration with Machines Pagès.

With the new packaging machine based on the Systec platform, Sumitomo (SHI) Demag offers an economic machine base for packaging injection moulding in a single application area. This is ideal for those not requiring the high-performance EL-Exis SP, previously established predominantly in the high-end sector of packaging injection moulding. The Systec SP also has a motor system that is optimally tuned with regard to speed, acceleration, precision and energy efficiency. Thus, the machine is equipped with a strong electric motor for the dosing procedure, as well as hydraulic motors for the mould and injection movements, which are supplied by a central, usage-optimised activeDrive “servo technology”. A hydraulic accumulator and a fast position-controlled hydraulic valve ensure highly dynamic injection. Further integrated technical components range from the active tool protection system activeQ, to the function activeAdjust, which offers the user the opportunity of accelerating each piece- or process-related individual machine movement, thus increasing the cycle time and with it, the productivity of the Systec SP. Naturally, all cycle-relevant axes can be moved in parallel.

Injection moulding cell for multitouch displays - IML for the function, IMD for the decoration

The manufacture of a multitouch display using a Systec 210 (clamping force 2,100 kN) documents the expertise of Sumitomo (SHI) Demag regarding complex, fully automated injection moulding cells with efficient and process-reliable mass production of innovative products. During the mass production of a 5” touch display, demonstrated for the first time on the K exhibition stand, the functional foils developed by PolyIC - PET-based coating foils with thin metallic conduction structures – are spray-coated with PMMA in the Inmold Labeling (IML) process. The narrow frame, which is also injected, is decorated at the same time using Inmold Decoration (IMD) in black piano lacquer finish. All the processes take place within the production cell in a cleanroom environment (ISO Class 7), from the insertion of the IML foil in the tool cavity, to the last of the multiple steps necessary for the post-processing, to the finishing of the display. The conductive IML foils used are optimised for injection moulding processing, and can be used for touchscreens to replace many of currently established foils, which are generally made of indium tin oxide (ITO foils). ITO alternatives are not only technologically but also economically very interesting, because indium is a rare heavy metal that is becoming increasingly expensive with rising demand. Furthermore, the very expensive laminating process of the foil on the carrier is not required.

The central coordinating point in the injection moulding cell is a suspended industrial robot, which Sumitomo (SHI) Demag realised, together with its system partners, for the respective process stages. In each cycle, it takes one conductive Inmold label from a stack and positions it precisely onto the solid half of the single-cavity mould. At the same time, the IMD forward travelling instrument, fitted on the closing side above the moving mould half, precisely positions a carrier foil with individual images for decorative coating of the moulded part space into the cavity. After closing the mould, the display is injection moulded in PMMA using a film gate and variotherm mould temperature control; the injected weight is 25 g.

Even if the most important part of the procedure is the injection moulding process itself, the subsequent steps taking place outside the mould in a 40 s cycle period considerably contribute to the quality of the piece and the economic value. After the six axis robot has taken an injected display frame from the mould and inserted a new label, it places the piece on a workpiece carrier. From there, the piece moves to a sealed laser separation station, where a CO2 laser with extraction system removes it cleanly and free from breakage from the film gate. Finally, the robot transfers the display to a UV-curing unit, in order to harden the covering topcoat lacquer of the decorative foil. For the last processing step, the robot transfers to the piece finally to the cleaning station, positioned below the UV station. Here, brushes ensure thorough and gentle removal of the residues of the IMD foil; loose particles are sucked from the edges without leaving a residue.