A highlight of the QuadTech stand was the new Color Quality Solution, which is uniquely capable of sharing and processing offline and in-line color data, thus ensuring a standard spectral color measurement procedure through the ink dispensing and printing stages. The solution comprises in-line spectral data obtained from QuadTech's SpectralCam, ink formulation data from X-Rite and ink dispensing technology from Huber Group or other ink dispensing system suppliers.
The process begins with customer-defined color targets. A spectral color curve is generated for each color target and loaded into the ink formulation software, which then formulates an ink recipe, based on the ink database.
The ink recipe is sent to the ink dispenser, which then prepares the ink batch for production. After successful quality control by means of a draw-down, the ink goes to press.
The color targets are loaded into QuadTech’s Color Measurement System with SpectralCam.
When the press starts up, color measurements are automatically taken and any color deviations are captured and reported in ΔE values.
Comparisons of printed work with the original color information begin immediately. If perfect color is not achieved, for example, due to contamination, a .CxF file is created automatically and sent back to the ink kitchen’s ink formulation software for fine-tuning of the recipe.
Furthermore, during the printing stage, the Color Measurement System shows real-time ΔE, solid density and dot gain values via an operator touch screen.
Stephan Doppelhammer, regional sales manager for QuadTech in Germany, Austria and Switzerland, says: “For the first time, color data can be shared in a common format and processed between in-line closed-loop color control and off-line color measurement technology. As a result, the packaging printer has an accelerated, assured means of arriving at color perfection and maintaining it to the final print. By simplifying one of the most time-consuming and complex stages of the make-ready stage, this solution offers potential for significantly reduced start-up waste and time savings.”
Stable, on-the-fly Measuring of Color on Different Materials
Another highlight at the QuadTech stand was a web stabilizing unit that enables spectral color measurements of transparent and opaque web material on-the-fly without risk of substrate corrugation.
The web stabilizer device consists of a flat-top, low-friction platform, onto which the moving web is stabilized by suction, to enable color measurement over a ceramic tile. The substrate is sucked down for a few milliseconds, in order to take color readings without wrinkles, bubbles and shadows that may result in distortion. Suction occurs when a vacuum is created around the tile, by pumping pulses of high-pressure air through a channel and out through small holes along the side of the tile. Multiple targets can be captured at one time.
The low friction-coefficient of the food-grade contact area prevents scratching or scuffing of either the surface area or substrate. The device contains a black and a white ceramic tile, allowing for precise color measurement on any substrate. Both tiles are slightly depressed, never coming into contact with the substrate. The tiles meet the British Ceramic Research Association (BCRA) ceramic color standard, guaranteeing a long-term constant backing value. The tile assembly is removable for easy cleaning.
The web stabilizer device is found in QuadTech’s Color Measurement System. This uses QuadTech's SpectralCam to accurately measure the spectral response and calculate L*a*b*, ΔE, Density and ΔDensity all at full press speeds, ensuring consistent and predictable results and minimal make-ready waste.