Profitable food packaging

With customers comprising a veritable who’s who of food processing multinationals, the Gerosa Group is one of the key players in the European flexible packaging market. Headquartered in Inverigo, the group was established in 1935 as a letterpress printing works while its rotogravure printing operations started in 1949.

Today, the Gerosa Group comprises five other companies: Flexocit in Italy, R2R in France, Cellografica Gerosa and Rieusset in Spain, Artema Plast in Romania – and two sales offices in Germany and Belgium. The Group’s gravure, flexo printing and converting capabilities for flexible materials are complemented by full prepress facilities for artwork preparation and in-house laser engraving technology.

In 2005, the firm installed a 10 colour Rotomec RS 4004 E rotogravure press with in-line coldseal capability. Designed for short production run applications, the Rotomec machine represented a break with Cellografica Gerosa’s tradition.

“Our extensive printing facilities comprised presses with the kind of technical specification best suited to cost effective, long runs at very high production speeds” explains Claudio Gerosa, the group’s md.

“However, the growing demand for shorter print runs prompted us to develop a project for a gravure line that is able to profitably print runs as short as 15,000m, or even shorter, with technical features that would allow a very rapid machine makeready” he says.

“The makeready solutions on the Rotomec RS 4004 E allow the press operators to set up the 10 trolleys for the following job at the same time without help from other personnel. As soon as a job is completed, they can start the next one. With an average printing time of one hour per job, we are able to perform more than 10 job changes a day,” he states.

Instrumental to the fast job makeready and change-overs is the trolley washing system, a special feature of Rotomec’s RS 4004 E press. After being automatically extracted from the press, the trolleys are entered into the dedicated washing machines where all parts are thoroughly cleaned without the need to remove any of them from the trolleys. Cellografica Gerosa has three such machines, which are housed in a separate enclosed area, adjacent to the RS 4004 pressroom.

Like all Rotomec gravure printing lines, the RS 4004 E features integration of the electronic line shaft with the register control system that is said to enable a faster correction of the register at start-up and at speed variations.

“The register control system is excellent, with rapid on-line detection of print defects and the level of waste is greatly reduced. Although the press is mainly dedicated to short run printing, it is suitable for longer runs,” says Claudio Gerosa.

Rotomec’s automation systems for fast job makeready and waste cutting proved so effective in fulfilling Cellografica Gerosa requirements that the company ordered another RS 4004 E press with the same general configuration, which will be installed in the course of this year. In 2007, the group also placed an order for a nine colour Rotomec RS 4003 for Rieusset.

Cellografica Gerosa’s core business is the production of high quality graphics flexible packaging for the demanding and competitive food packaging market, as well as cosmetic, medical and detergent segments, and one of the company strengths lies in technically advanced composite packaging materials.

The latest addition to its extensive converting capabilities has been a Rotomec CL 1000 triplex laminator, which has been in operation since early 2007.

“Our main consideration was the ability to coat thin aluminium foil at high speeds as the new laminator was to be mainly dedicated to the production of sophisticated triplex structures that would include this material,” explains Claudio Gerosa.

Cellografica Gerosa’s CL 1000 includes two flexo coating groups for the high speed coating of solvent based adhesives directly on aluminium foil as thin as 7 micron.

Rotomec’s flexo coating system can be used to apply a lower adhesive coating weight and is said to offer high efficiency drying that brings the residual solvent value very close to zero. Also, the system design prevents the occurrence of foil breaking as well as the formation of orange peel defects on the laminated web.

The laminator is equipped with shaftless winders with automatic splice at maximum line speed. It also offers all round flexibility of process as it provides for one colour printing and duplex lamination in one pass.

“We are very satisfied with the high performance of this laminator,” concludes Claudio Gerosa. “Production speed is up to 450m/min and the machine delivers exactly what we were looking for - superior optical quality laminates with high barrier properties cost effectively produced due to high speed performance with a wide variety of possible material combinations, and very fast machine makeready and job change-overs.” n