The automation of packaging lines also includes the printing of product information such as texts, codes, and logos. Though the selection of print systems is indeed large, database connections and printing of variable information in rapid alternation tend to be less common – even in coding and marking systems. This requirement was needed at Ciba in Lampertheim, for example, for use in their light stabilizer production process. These are additives which are applied to plastics to reduce the effects of the UV radiation and thus improve durability. They are produced here, where they are sacked and then packaged in cardboard boxes.

 

The packaging station is the point of contact for two production lines with different products. It is therefore essential to ensure that the cardboard boxes can be labeled using the labels 1 or 2 alternately, depending on which conveyor is delivering the product. This is because as soon as the robot has picked up the sack from one of the two conveyors with the gripper, the cardboard box is printed with the relevant product data and conveyed to the loading position. The printer that was initially being used was not up to this task, as the assignment of new print fields or variables was too time-consuming. In other words, the packaging lines and the fill stations either had to be slowed down or stopped. The conveyors would only resume once the printer had printed the new text and was ready for printing. Considering these limitations, it was simply not feasible to achieve a high output. In addition, there was the problem that the impression was not applied with ink but with hot wax, which always dried up after long pauses.

The final decision for a new coding and marking system was made when an additional label was required for the SAP implementation. Since there had previously been two labels positioned side by side in a row, there would not have been enough space for a third. The design on this printing system did not allow an additional print head for a second row either. The main requirements for a new coding and marking system were therefore clear: An ink jet printer with two print heads for an overall height of at least 140 mm, a network protocol for rapid communication, a database connection, and the coupling with the production SPS.

The new solution for the packaging line at Ciba Lampertheim GmbH was provided by REA Elektronik, a company with expertise in every area of printing technology. Ranging from large and small character to high-resolution printers (as with Ciba) and including HP-based versions and laser systems. "The key factor in the decision was that REA offered an all-in-one package and was a turn-key solution," says Karlheinz Mattern, a project planning engineer at Ciba. Though the print heads are purchased separately, as is standard with other manufacturers - the ink systems, electronic components, and especially the software are designed and developed in house. The special feature of the new DataCon software is the ability to integrate different databases and systems, even when they speak “different languages". In this way, the customer's existing infrastructure can communicate and exchange data efficiently - one of the requirements for quick and automatic assignment of print contents.  

On request, the software can even be customized to meet specific customer needs. This is the great advantage when it is directly developed by the manufacturer. Ciba has benefited from this opportunity. Not only are the cardboard boxes filled with different products from two lines, but each cardboard box is additionally assigned an internal sequence number. In exactly the same way as the label text, this needed to be assigned automatically when the product changes and integrated into the sequence of the feed- and packaging lines. REA's task here was to assign the correct data to the print heads at the right time. The procedure is as follows: First a print order is issued from the SPS to the REA DataCon software, or the printer PC, via OPC. The latter then uses SQL to access the Access database and automatically transfers the required text elements and logos into the print layouts. In this way all the required data is available online and flows dynamically into the current production. A similar process occurs with the sequence number. This number is managed by the SPS, is incremented starting with a specific starting number, and is likewise transferred to the printing system.

The GK 768/256 ink jet printer from REA used at Ciba is designed for coding and marking on absorbent surfaces and by default includes an Ethernet port. Linking it to the network via TCP/IP enables rapid data communication and product speeds of up to 200 m/min. The print head has a print height of up to 100 mm, 256 selectable channels, and can print up to 42 lines simultaneously. It handles all the common linear barcodes and 2D codes, as well as a 2D DataMatrix code (a GS1 128 is used at Ciba). Users can use up to 100 variables (texts and logos) per print head for linking with the database.

With this coding and marking system even an additional label is no longer a problem. With two print heads mounted one above the other, the heads reach 200 mm and print the texts and logos retrieved in two rows. The first one holds the product name and product information, the batch number, along with company address and emergency contact number. The second row contains the hazardous material information for handling and storage, along with related symbols. Up to two product-specific hazard symbols can be printed in the orange field provided on the cardboard box. The ink is not only smudge and scratch-proof, it is also sea-water resistant. Likewise, a requirement at Ciba. Supply occurs via the controller using cartridges of 125 and 500 ml, which can even be changed during printing. A useful aspect for the operator is the optional maintenance module, which can be used for cleaning the print head, for example in case of excessive concentration of dust in the surrounding air - just press once and the cleaning process is performed automatically. This minimizes the effort required for maintenance and increases the output in packaging.

The automatic assignment of print texts described here with the new DataCon software is suitable for all of the company's coding and marking systems. The user can therefore not only choose from different print technologies, but they can also be combined without interrupting production. This increases flexibility and thus the level of automation in production and internal logistics. And here is another piece of good news: The customer-specific software which was initially developed for Ciba is now available to all customers as a standard solution.