Packaging with creases: imperfection with intention

A label with creases — a no-no, but at the Mozart Distillerie in Austria this imperfectionism is quite intentional. The shiny paper foil wrapped around the spherical chocolate liqueur bottles quite deliberately evokes the impression that it has been applied by hand.

In the past few years, output at the Salzburg-based company has more than doubled, producing over 650,000 L of Mozart Chocolate Liqueur in 2019.

Each of the five different chocolate liqueurs are traditionally produced by hand and bottled automatically. But according to Friedrich Guggenberger, Plant Manager of the Mozart Distillerie, the 30-year-old, custom-built bottling machine was struggling to keep up with the increased production demand, and it was hard to find an alternative solution that met their unique requirements.

“Since we wrap our spherical bottles in full-coverage paper foil, we always create creases. And whereas every manufacturer of labellers tries to prevent this, we actually want them, because they give the impression that the containers involved have been labelled by hand,” Guggenberger explained.

“The foil has to fit snugly round the bottle’s body, but in the vicinity of the neck and the base it has to be folded in such a way that it does not twist and subsequently disappears reliably underneath the capsule closure.”

But that’s not all: the machine was also required to incorporate monitoring systems that inspect the labels and the foil for correct placement and for integrity as well. What’s more, the bottles must not turn on the downstream conveyor, so that they enter the capsule closer in the correct orientation.

Krones accepted the challenge — and combined the long years of practical experience and visions of Guggenberger and his team with the technical expertise of its own labelling specialists.

The creasing solution

After being filled, the bottles enter the labeller through a double worm. An optical monitoring system then centres them so that the sloping area for the label is facing outward.

An optical monitoring system at the infeed centres the bottles in such a way that the sloping area for the label is facing outward.

Thereupon the aluminium-coated paper foil is affixed. To make sure it does not slip, first of all, a dot of hotmelt is sprayed onto the bottle and then the fully glued foil blanks are wrapped around it. For this purpose, Krones is deploying a combination of one cold-glue and one wraparound Contiroll labelling station.

The next station uses a sponge to press the foil against the sloping area in such a way that afterwards the pressure-sensitive body labels can be applied to the creaseless front of the containers.

This is followed by an operation that basically every labeller manufacturer tries to prevent: creasing. For this purpose, Krones developed a patented combination of a servomotor, which turns the bottles, and linear motors, which in 12 press-on operations use sponges to carefully press the foil onto the containers.

To enable the foil to be dependably secured at the edge of the base as well, Mozart was already using a small bottle plate in the old line, which raises the containers merely by a recess in the base. This means the edges of the bases remain free and the sponges can fit the foil around the edge. In the discharge, a transfer starwheel then lifts the bottles carefully onto the conveyor. Meanwhile, a Checkmat inspector monitors the base label already applied downstream of the filler for correct position and orientation.

The pressure-sensitive body labels are applied to the sloping area at the front of the container.

The position of the closure cap then applied is also precisely defined. In order to prevent the bottles turning as they travel, Krones has developed a guide rail that transports the bottles with the aid of the sloping label area as an orientation reference point. These rails can be re-adjusted with only a few manipulations, so that all six sizes — from the small 50 mL to the large 1 L bottle — can be handled with the same system.

“I know that we had very many requirements for this labeller — but Krones met all of them. And the result is highly impressive; no other manufacturer could have managed it,” Guggenberger said.

The new line is currently dressing around 5000 bottles per hour, with an option for increasing the output to as much as 9000 bph. And although the labeller now operates fully automatically in line with the very latest state of the art, to the outsider’s eye Mozart continues to embody its craft operation. Because no one crease resembles another — and the labeller handling the containers is just as unique as every single container it dresses.