It’s all about the perfect print result

Schattdecor is an internationally leading German family owned manufacturer of surface decorations located in Bavaria. To meet the challenges of the increased quality requirements of the world markets it upgraded its gravure printing presses with the latest generation of BST inspection and web monitoring systems.

Tailored to the conditions in gravure printing, the pilot system proved so successful that Schattdecor decided to purchase 12 BST inspection systems iPQ-Check and web monitoring systems iPQ-View each. Eight of these systems each are installed at locations in Germany.

Modern surface decors from Schattdecor meet current trends. The surfaces, which are produced using gravure or digital printing, are used for furniture or laminate flooring and also to design caravan interiors as well as public spaces. Visually, the decors are in no way inferior to natural materials such as wood or stone. Based on textiles, sand or concrete, as well as pure fantasy decors, the company’s latest developments inspire customers all over the world due to their authenticity, colour brilliance and design.

As a high-speed printing process for premium products such as decorative paper and foils, gravure printing in particular requires the highest precision and continuous, full-coverage quality control. At the same time, material and energy costs as well as waste must be kept as low as possible. So it’s all about nothing less than the perfect print result, i.e. making printing processes as profitable as possible and fully satisfying every customer.

The challenges of gravure printing

Schattdecor has been working successfully with BST for many years. Now the challenge was to find a solution for the increased demands in gravure printing. For example, this means to display decors in full width and to ensure a particularly high accuracy when displayed on the screen. Particularly in decoration printing, it is a great challenge to detect misprints of faulty substrates accurately and at an early stage. This is due to the fact, that they are hardly to detect at grained wood décors or vivid fantasy designs. “In the past the press had to be stopped to remove a sheet from the roll and check it. With the new systems by BST this step can now often be avoided. In case it does become necessary, reaction times are significantly reduced. This relieves the press operators in terms of quality control and saves substrate waste”, explains Josef Maximilian Hintler, project engineer at Schattdecor.

Faster than the human eye

Conspicuous features in the decor are automatically reported by iPQ-Check and visualised in high resolution by iPQ-View. Thanks to the high resolution of the cameras, they are inspected without interrupting the printing process. The systems are many times faster than the human eye. They detect recurring defects as well as one-off defects with absolute reliability and allow for immediate assessment at running speed. Subsequent quality checks on rewinders or the interruption of the production process can often be avoided in favour of efficiency. During quality control, machine operators are supported by a complete logging of events that have occurred. iPQ-Check and iPQ-View are the basic modules of the versatile iPQ-Centre system. Various additional functions such as additional cameras, screens or special lighting options are optionally available.

100% print image inspection at full production speed

As an innovative 100% print image inspection system for quality assurance, iPQ-Check enables print image inspection across the entire print format and can be fully integrated into the digital workflow. At press speeds of up to 1000 m/min and web widths of up to 2800 mm, three high-resolution line-scan cameras combined with LED illumination detect defects in real time and deliver detailed colour image data. In total, a machine can be equipped with up to four cameras. Even on vividly patterned decorations, iPQ-Check detects defects such as veils or stripes reliably and quickly. This allows operators to intervene immediately, quickly eliminate the cause of the error and avoid waste and thus costs. Incidentally, iPQ-Check is also suitable for highly reflective materials, holograms, translucent substrates and highly flexible substrates.

The intuitive operating concept minimises reaction times and frees the operator to do other tasks. Christoph Kalb, project manager at BST, mentions further advantages: “The iPQ-Check is the ideal solution for first-class print image inspection. The system not only delivers reliable results, but is also fun to use. In addition, further iPQ products can be integrated into the user interface at any time.”

High-precision web inspection for faultless print products

As a perfect complement to the iPQ-Check inspection system, the previous web video systems from BST/Eltromat have been replaced by the advanced iPQ-View web inspection system. Serving as a highly effective quality control device, the digital web inspection supports the continuous monitoring of the production results.

Coupled with high-resolution 3-chip HD cameras, the system’s intelligent image processing software enables print image visualisation of the running web in high detail and colour fidelity. Even weak contrasts are displayed, meaning that “invisibles” such as missing varnish or fogging can be made visible. At the touch of a button, the image is displayed with enhanced contrast. Based on such visualisation, well-founded decisions can be made for visual quality assurance and subsequent adjustments. Volker Reinholdt, product manager at BST, emphasises: “The iPQ-View leaves nothing to be desired in terms of image quality and range of functions and enables full print image inspection. As part of the iPQ Centre, the products integrate seamlessly into uniform user interfaces.”

User-friendly interface

Both the iPQ-Check and the iPQ-View are integrated on the iPQ-Centre’s intuitive multi-touchscreen interface, whose most prominent feature is a clear error display. For this, each fault is documented with the first and last faulty image as well as the image of the most severe fault. This enables quick and realistic decisions to avoid waste.

Tailor-made installation

Before using the new systems at Schattdecor, adjustments had to be made to suit the conditions in gravure printing. This is also due to the fact, that iPQ-Check has never been used in decorative printing before. During the test phase, the system was adapted in such a way that it now detects faults even in wood decors with branch structures and changing grain patterns.

To make space for the system in the existing press, a steel structure was developed through which the printed paper web is additionally guided. The customised installation means that the system is well protected but still easily accessible. The additional screen was inserted into the ergonomic control console so that the press can be monitored and adjusted from the console. During the test phase, minor optimisations were made to adapt the system to the special requirements of decoration printing.

The installation of the BST systems including cabling and insulation was carried out by Schattdecor itself. In addition, the construction of the steel frames for the mechanical integration of the systems was carried out by a partner company.

Smooth commissioning after extensive testing

The pilot plant was intensively tested for a year to meet all respective challenges. The installation of the systems required only two to three days per machine. During commissioning, a BST technician checked the complete cabling once again. In addition, the staff was trained and final optimisations were made.

Conclusion

Schattdecor has been using systems from BST/Eltromat for over twenty years. These include web inspection systems in various generations as well as register control systems. The 100% inspection iPQ-Check is now a valuable addition. Hubert Rothmayer, who has been with Schattdecor for more than 20 years and knows how the printing trade has changed since then, remarks on the system’s advantages: “With BST we have a reliable and competent partner with whom we have been working for many years. From the reliability, user-friendliness and performance of the systems to the range of services and support – everything is just right!”