The color management and quality control density meter in flexo printing will replace the magnifying glass

Controlling the quality of printing and checking and evaluating the quality of printed matter is a complicated issue. The traditional method is only to observe the printed matter with a simple method, such as using a magnifying glass to observe whether there is an increase in deformation of the dot, and then comparing the printed matter with the original, and often neglecting it. The complexity of the cause of errors in prints. There is no scientific basis for this subjective judgment on a printed matter that depends purely on human factors. In addition, with the wide adoption of FM screening technology and digital proofing technology, methods that are accustomed to observing AM screens with a magnifying glass have gradually been eliminated.
Printing requires scanning, color separation, computer production, film output, plate making, printing and post-press processing, and other complex links. Separating equipment, printing presses, ink, and paper will all affect the printing quality. From the manuscript to the color separation film, the color separation film to the printing plate, the printing plate to the final printed matter, errors may occur at each link, and problems may be effectively controlled and avoided, or the errors and losses may be reduced to Minimally, it is the highest requirement for printing that the original is copied to the maximum degree.
In general, the assessment of print quality is nothing more than from the reproducibility of hue, inhomogeneity, the sharpness of the image, and the stability of quality. Then, we must control the quality of printing from the detection of film, print, and printed matter output by color separation. Both the quality of the film and the quality of the printing plate will affect the quality of the printed matter. Detection of the film, printing plate, and printed matter using special testing equipment can accurately determine the specific parameters and provide reliable data for printing, standardization, and modern production. Technical information.
The flexographic prepress portion is as important as the other print methods. Image color separation and film output are critical for the entire print. In addition to the selection of best-in-class hardware and software, it is more important to use transmission densitometers to test the dot gain and density values ​​of the four-color film to ensure non-forest quality. The standards for image color separation and film output are clear gradation, complete gradation, and correct color.
The most special part of flexographic printing is the plate making process. From plate-making materials to platemaking processes, flexographic printing is very different from other platemaking methods. Because flexographic printing uses a flexible resin plate, when the flexographic plate is pressed, the dot enlargement rate is large, and the printing plate is transferred to the surface of the substrate. Inevitably, the printing of four weeks around the dot is enlarged. Unlike the square-shaped and chain-shaped screens of offset printing, flexographic printing uses the circular-shaped screen with the shortest circumference, so the shape of the web changes, and the place where the highest dot is expanded also changes. Therefore, compensation must be given during the plate making process. As for the number of high screen lines, the longer the total perimeter of the network, the larger the dot gain value formed during printing.
During the plate-making process, the small dots in the high-light part of the thin network cable absorb more solvent during flushing after the printing, resulting in greater expansion. Due to the peculiarities of the flexographic platemaking process, it is difficult to accurately assess the quality of the flexographic plate based solely on experience. In addition to the advanced plate-making equipment and software support, the plate-making company also has experienced masters of plate-making and flexographic measuring instruments. VIPTRONIC's VIPFLEX 333+ densitometer can be used to measure flexographic dot area, lines per inch or centimeters. The obtained parameters are evaluated to objectively determine whether the printing plate meets production requirements.
Lai spectrum VIPFLEX 333 + quality control device consists of measurement hardware and a software program system. The measurement hardware is equipped with a CDD camera with an area of ​​1.5 x 1mm. The ingested image is sent to a PC and analyzed by a software program. The evaluated area is displayed on the image as a red grid and checked by the operator on the display. The red circles and lines on the display indicate that only good points will be calculated, while damaged points will not affect the dot area and the number of lines. VIPFLEX 333+ also calculates a new parameter “contour factor”, which describes the relationship between the perfect circle and the true shape of the mesh, and gives the measured results of damaged meshes and irregularly shaped mesh points. VIPFLEX 333+'s "Eye-Eye" window software can complete and measure several parameters of reflection and transmission in one second: "dot size", "contour factor", "varicolored" and "number of lines/cm or inch" .
Laipu VIPFLEX 333+ density meter can measure the dot area and the number of network lines/cm or inch on the transparent flexographic, film, lithographic and printed products, and can automatically measure the percentage of screen points and screens of the transparent flexible version in a few seconds. Contour factor. The application of VIPFLEX 333 + simple and fully automated measurement methods enables problems to be quickly discovered and resolved quickly, taking quality control to a new level.
Reed Spectrum VIPDENS2000 is the world's first color measurement with 7 colors, multi-language display, interactive multi-function densitometer, the operator can complete all the measurement functions on the four-line LCD display. This kind of density meter with automatic colorimetric function does not need to use any buttons and can automatically perform various identification functions. Reed Spectrum VIPDENS2000 has a wide range of measurements, with up to 30 measurements and a measurement time of less than 0.4 seconds. It has seven color determination functions for cyan, magenta, yellow, orange, green, blue, and black and can also measure spot colors. The spectral function of Reed Spectrum VIPDENS2000 spectrometer can store up to 9 sets of reference data at the same time, providing users with scientific proofreading standards when testing and visually evaluating prints. (China Packaging News)