KBA North America, a global press manufacturer based in Dallas, Texas, is introducing its new and unique DensiTronic PDF reader for its sheetfed offset presses. This new scanning system can be easily added onto the press as a part of the KBA DensiTronic Professional closed-loop scanning spectrodensitometer system that provides density and color measuring for quality control both during and after printing.

"Once again KBA leads the industry with the introduction of a highly-automated PDF reader," says Chris Travis, KBA director of technology. "KBA customers who use this system can provide assurance to their customers that they are capturing every pixel from the approved PDF onto the printed sheet thus assuring a perfect match. The printed sheet is compared to the original PDF resulting in less waste and achieving the required quality faster."

The DensiTronic PDF reader provides a wide range of benefits for its KBA customers. It provides detailed documented quality reports from the printer, and reduces waste since errors are detected at the beginning of the press run. "The DensiTronic PDF reader provides reliable detection of small, difficult-to-spot errors," says Travis. "It is the only integrated system with 300 dpi resolution and detection and the only system designed for sheets up to 47 x 64-inches."

One of the first KBA customers to install the DensiTronic PDF reader is a large German packaging printer specializing in the pharmaceutical and cosmetic markets. Since DensiTronic PDF went live, this company has been able to reduce its already low costs for returns and complaints by an additional 50%. The greatest potential for savings lies in avoiding errors during printing. The DensiTronic Professional and the PDF reader add-on installed on both of the customer's two KBA Rapida 105 presses have given a boost to production reliability and quality awareness within the company. The employees have fully accepted the new electronic tools and are able to feel even more confident in the quality of their work. While the majority of its competitors rely exclusively on color measurement or control, and only a few perform an additional comparison with a reference sheet, the KBA German packaging company compares its production with the original PDF files provided by the customer. With an inspection resolution of 36 measuring points per square millimetre, the document comparison reveals even the tiniest deviations in the printed image, many of which would probably have remained unnoticed during a normal check with the naked eye. To this end, the printer on the press uses the KBA DensiTronic PDF reader to scan the first good sheet of his run. The automatic evaluation pinpoints even the slightest deviations from the original PDF within just a few moments. Alongside any spots of dirt which may have contaminated plate exposure, the system also detects additional die-cutting and register marks on the sheet, the numbering of individual blanks, dot gain in the packaging barcodes (when printing on inexpensive card grades) and the like. The facility for automatic exclusion of individual detected differences enables the operator to gain a fast and compact overview of all production-relevant deviations. He can then decide whether the job can be printed as it is, or whether consultation with the quality assurance department is necessary.

Here's how easily DensiTronic PDF reader works:
- Operating software for the PDF scanner is integrated in the DensiTronic Professional standard user interface
- A scanner beam incorporating a series of individual cameras produces an image every .7874 inches
- Scan resolution 300ppi
- Measuring time is approx. 60 seconds in 29 x 41-inch format
- Individual elements stitched into an overall image on the system computer
- Overall image passed to the quality control program
- Parallel import of the reference PDF (automatic or manual)
- Definition of the monitoring parameters (error size threshold, error contrast, max. dot gain from squeeze, max. register offset, color mode, resolution) via simple screen menus
- Comparison of the overall image against the PDF file
- Test certificate plus comprehensive reporting and evaluation functions are produced as either a simple, single-page statement to a detailed report, either as a PDF file or in paper form.