Event dates: May 04 – May 10
Location: Düsseldorf, Germany
From the initial idea to the thermoformed premium cup
The eye appeal is used to encourage customers to buy, where numerous similar products compete with one another in a small area. This especially applies to food articles in supermarket shelves. Brilliant decoration in photo quality can considerably increase the promotional effectiveness for dairy products since in particular in this sector numerous products of the same type are presented closely together mostly in thermoformed packs. The method of choice for this is in-mold labeling in thermoforming (IML-T® or respective also T-IML®). Not only packs are manufactured with premium decoration, moreover, also functional requirements are fulfilled, such as product protection by the barrier effect, withstanding retort and hot fill processes, break resistance under high stress (top load), benefits in logistics and the high output which can be achieved results in high efficiency.
Benefits of T-IML® technology
T-IML® has been gaining significance compared to surface decoration of thermoformed packaging by means of subsequent printing, sleeving with printed shrink film or by application of printed paper labels. Even cups of a combination pack (product family) can be individually decorated something that is not possible by printing. A benefit of the T-IML® method is the ability to change decoration quickly and easily. Packages of most geometries can be flexibly decorated with labels. Full-area labels reaching up to the cup rim which also merge seamlessly with the cup material with brilliant design at the same time can only be realized by T-IML® in thermoforming. IML thermoforming is clearly more favorable with regard to cost aspects than IML injection molding. The cost factor per pack is a clear advantage in thermoforming. With the same label price, thermoformed items can have thinner walls and thus weigh less than their injection molded counterparts. In addition to this considerably lower material consumption, the energy requirement for thermoforming is lower. T-IML® thermoforming provides economic advantages because of the ability to work with molds of up to 18 cavities and at higher machine cycle rates than those for injection molding. Today’s T-IML® technology provides many possibilities and opens up many opportunities: Labels can be applied on one side, two sides, three sides (e.g. in the shape of a U), four sides or even five sides (including bottom decoration with integrated barcode, for instance) full area until the cup rim. T-IML® makes it possible to combine high-quality visual appearance with functionality. Depending on the requirement, overlapping label surfaces as well as free packaging surfaces are possible. Labels out of standard material can be processed, from polystyrene (PS) and polypropylene (PP) to paper labels. When matched to the cup material, this makes recyclable and sustainable packaging possible.
Suitable multilayer film for special barrier effects can be employed in thermoforming. Since T-IML® does not require vertical walls, this decorating technique offers the additional benefit of being able to enhance product presentation on the supermarket shelf further with a custom packaging design. The RDML 70b offers the required flexibility to produce decorative T-IML® thermoformed parts with a variety of geometries and sizes in a cost-effective way. Today, the quality of thermoformed T-IML® decorated cups is comparable to the standard achieved with injection molding. When it comes to the availability of the production line, IML thermoforming is at the same high level. For quality control it is also possible to employ inspection stations with camera systems and color sensors.
Complete barrier layer
All listed technical arguments in favor of the T-IML® technology were decisive for Coveris Rigid France to make a project request to ILLIG Maschinenbau, Heilbronn, for development of a premium cup. The task was to realize a 250 g butter cup with UV barrier layer, decorated with T-IML® technology for the Président product line of the Lactalis Group, a family-owned dairy group based in Laval (Mayenne), in the west of France. The basic cup shape is decorated with three different PP labels, subject to content, bar code and language – a flexibility with only one cup mold which enables the T-IML® technology, because decoration can be changed fast and easily.
Coveris has developed a T-IML® PP cup with UV barrier and fatty product for the cooling chain. UV barrier layer was important for Lactalis, by thermoforming of a multilayer sheet which is not completely possible in barrier injection molding. The 100 percent UV barrier allows an extended shelf life of the packed product. A further aspect was the cost-effective technology since the products are decorated already after forming.
Right from the beginning the customer wanted the decorated cup to be a sustainable package with premium all-around decoration. Cup and label should be made out of the same PP basic material for easy recycling. This goal was reached by the two companies and the packaging is totally recyclable as label is made of the same material than the packaging. In this case in polypropylene.
Coveris offers also other truly sustainable packaging solutions: Weight savings of up to 20 % can be achieved (as a result of a density decrease) by using foamed, lightweight multilayer sheets like NEOCELL® or NEOCELL+® with a gas-injected middle layer and optional filler materials.
Packaging development, prototyping and mold design including layout of the thermoforming machine were carried out within a short time. The result can be found today at the Coveris site Auneau, west of Paris: An IC-RDM 70K of the latest generation with a 15-up mold and corresponding 15-up label station. The production line is additionally equipped with an optical quality management system. 18 cameras check the label artwork and label positioning within milliseconds at a speed of 16.5 cycles, depending of the sheet thickness. Defective parts are discharged by the stacking system by means of compressed air.
Coveris, the manufacturing company, was very satisfied with the developed T-IML® solution. The ILLIG IC-RDM 70K thermoforming line employed by Coveris together with the T-IML® RDML 70b unit produces tens of millions of cups per year decorated with UV barrier properties and various designs.
T-IML®mode of operation
The sequence of in-mold decoration is described based on the RDML 70b packaging machine which was designed particularly for T-IML® decoration. Suction plates remove labels for the magazine and transfer them to a pre-forming device which pre-forms the plane label blanks to the contour of the thermoformed part. At the same time the format of the magazine, i.e. the distance of the labels formed to part contour, is adapted to the center cavity to center cavity dimension of the forming/punching tool.
These process steps are performed synchronously while the pre-forming and reformatting station moves to a position where it transfers the labels to a pivotable transfer unit. With its suction mandrels the transfer unit picks up the number of pre-formed labels matching the number and position of tool cavities and with the empty suction mandrel side pivots to the waiting position in front of the still closed mold. After the mold opens and the lower mold half tilts by 80°, the formed cups are removed from the cavities by the transfer unit. After pivoting by 180° it places the new labels into the mold cavities for the next cycle. The transfer unit with the thermoformed parts returns to the label pickup position. Here, a two-axis linear robot equipped with suction cups takes the decorated cups, transfers them – if set up in this way – with an intermediate stop to an inspection station to check the quality of the decoration on each cup and then finally to stacking. Stacks are removed horizontally, at most six rows at a time.
The RDML 70b machine features the same forming area as a conventional IC-RDM 70K (680 mm x 300 mm). The most prominent distinguishing feature is that in the T-IML® line which is of the same size, the stacking station is replaced by the label station. It incorporates all devices required for T-IML®, such as magazine for label storage (the number of label positions for manual feed of the label stacks results from geometry and size of application; ILLIG already realized in the Form-, Fill- and Seal-Line with IML-T® unit FSL 48 even up to 24 cavities), label singularization, pre-forming and re-formatting device, label and cup transfer unit as well as two axis handling system to pick up and stack the IML decorated parts.
With this equipment level, the RDML 70b achieves a production output of approx. 25 cycles per minute, regardless of whether the cups being decorated are round or not. Depending on the part and label, forming itself involves merely about 450 ms. For round parts, the minimum diameter (punching dimension) is 75 mm; for rectangular parts 75 mm x 75 mm; the maximum cup dimensions are limited by the maximum label size of 300 mm x 300 mm that can be processed. The minimum label size is 100 mm x 100 mm.
IML-T® and T-IML® are registered and protected trademarks of ILLIG Maschinenbau GmbH & Co. KG.
DuoSmart® is a registered and protected trademark of Coveris
NEOCELL® and NEOCELL+® are registered and protected trademarks of Coveris
Georg Sposny responsible for Marketing Communications, Public Relations at ILLIG Maschinenbau GmbH & Co. KG, Heilbronn; firstname.lastname@example.org