When it comes to costs, every single millimeter of board counts for packaging printers. The latest software version of the Prinect Image Control color measurement system once again sets new standards in this respect. With this system, the development engineers at Heidelberger Druckmaschinen AG (Heidelberg) have succeeded in controlling coloring on the press using nothing but full tones and CMYK images on the print sheet. The process uses CIP4-PPF data (formerly CIP3) from the prepress stage and is highly automated. In many cases, this means there is no need for a conventional print control strip at the edge of the sheet. Depending on order volumes, just this 4 mm reduction in the amount of board required can save between €20,000 and €40,000 each year.

The new Prinect Image Control was demonstrated in early May this year at the Packaging Days in Wiesloch-Walldorf. A further benefit in addition to the material saving achieved by the absence of a conventional print control strip is the Proof Match option, which optimizes the uniformity of multiple ups on a print sheet. A new and unique feature is that it is now also possible to use digital proofs as color samples and set up the press accordingly to the proof’s color information.  

The new software is available with immediate effect and can be retrofitted on all IPEX 2010 generation Prinect Image Control systems. Over 2,000 systems have been installed since the market launch of Prinect Image Control in 1998.

Prinect Image Control can be connected to between one and four presses, which makes it a cost-effective way of also enabling existing presses to deliver optimum color accuracy. Connection to all Speedmaster presses in the 52, 74, 75, 102, and 106 series is possible.

In addition to Prinect Image Control, Heidelberg also offers the Prinect Inpress Control inline color measurement system, which has proved a hit with industrial-scale print shops thanks to its impressive productivity. Prinect Image Control is ideal for extremely narrow color consistency tolerances in applications such as hair dye packaging, labels, and also long runs on poor-quality board where paper dust quickly clogs up the blanket and thus affects the print image. It is the only system in the industry that measures the entire print image and not just individual dots. This quickly detects and corrects any change to the print image. 

No more print control strip

Many layouts in packaging printing enable color control elements to be positioned between the individual repeats or on glue flaps. Such elements use Prinect Image Control, together with the full-tone areas in the repeats, for color control on the press. The correct position, size, and color are taken from the CIP4-PPF file. The necessary information is available as soon as the job has been loaded. There is no need for the printer to assign it manually. Color control is based on all full-tone areas in the print image, which means there is often no need for a conventional print control strip. What’s more, a degree of inking uniformity is achieved that would be impossible using only a print control strip.

High added value for manufacturers of branded goods – optimum color matching of repeats thanks to Proof Match 

CMYK images supplied for a repeat can also be scanned in and archived along with the full-tone areas. Once Prinect Image Control has measured the first pull, the printer loads the sample from the archive. The Proof Match function identifies identical repeats on the print sheet fully automatically, displays these on the monitor, and compares the coloring of the print sheet with the correct coloring on the sample. Recommended settings for the press’s ink zones are then calculated accordingly. This ensures that the coloring of all repeats matches. It also works with repeats from a freshly printed sheet. The printer selects the repeat whose coloring is to be used for all the other repeats and Prinect Image Control does the rest automatically. Many printers are already familiar with this function from the first-generation Prinect Image Control system. The innovation is that digital proofs, from an inkjet printer for example, can now be used as the sample.  

Commercial printer uses Proof Match for precise coloring and faster processes

B&K Offsetdruck GmbH in Ottersweier, Germany is renowned for its high-quality sheetfed offset printing for advertisements, image brochures, and illustrated books. “We receive proofs that we match on the press in consultation with the customer. Before we started using Proof Match, it wasn’t unusual for six or seven adjustment stages to be needed, with all the waste paper that entailed, to get very close to the proof and thus achieve a salable result,” explains Hans Geideck. As a color management expert, he has seen how Prinect Image Control has developed at B&K from the outset and is now delighted that things work faster. “Since we’ve been using Proof Match, we often only need two pulls. Further optimization is then achieved with a maximum of three control steps on the fly, which saves us a great deal of time and setup waste. As well as ensuring reliable results for our customers, the quality of their runs is always documented by the reports of the integrated Quality Monitor, which is a big help in the event of a complaint,” continues Geideck.

Prinect Image Control goes further still at B&K. “Naturally, end-to-end color management is a basic prerequisite for successful use. The proof and print need to match. By measuring the Fogra media wedge with Prinect Image Control, we already know before the first pull whether correct reproduction in print is actually possible. We involved our printers in the process at an early stage so that everything runs smoothly. They were skeptical to start with, but now they’ve been won over by Prinect Image Control,” says Geideck.

Unique feature – opaque white can now finally be controlled

Uniform printing of opaque white in an offset printing unit is a big challenge in packaging and label printing. Up till now, the quality of chromatic colors has always depended on how skillfully the printer visually set the opaque white underneath and kept it constant. Prinect Image Control is the first color measuring system that is able not only to measure and display opaque white, but also control it. This even works when opaque white needs to be printed in several units, as is normally the case with foil and reverse printing. Since opaque white is usually completely overprinted with chromatic colors in the print image, measurement takes place exclusively in the print control strip. One measuring patch for each opaque white in the print control strip is sufficient. 

“We print labels on aluminized paper from the reel. We have long been using color measuring technology from Heidelberg to measure and control chromatic colors, but we had to measure and control opaque white manually on aluminum with a hand-held densitometer using a method we developed ourselves,” explains Josef Stelzle, head of department at Engelhardt-Druck GmbH (EE) in Nördlingen, Germany. “We have now further developed our EE method in collaboration with Heidelberg so that Prinect Image Control can measure and control opaque white automatically for the first time,” he adds. The new Prinect Image Control function helps in several ways here. The opaque white stabilizes faster and remains more uniform, which means the same applies to the chromatic colors. “That saves us around five to ten minutes per job. Thanks to the spectral measuring technology, we also detect ink soiling much earlier and can take the necessary action,” says Stelzle with evident satisfaction.