High quality of newspaper printed matter originates from detection technology
the most important thing in newspaper printing is the printing quality of newspapers, which is not only the basis of customer satisfaction, but also an important technical means for newspapers to succeed in commercial trade. In recent years, with the popularity of color newspaper printing, the advertising board is becoming an integral part of the newspaper layout. The continuous expansion of advertising space not only brings good economic benefits to the newspaper, but also puts forward higher requirements for the printing quality of the whole newspaper. Therefore, newspaper printers will inevitably face increasing pressure and challenges, and have to face up to the growing calls and requirements for improving the printing quality, especially the printing quality of advertising. Therefore, in order to cope with this change, many newspaper printing centers have begun to pay attention to the advanced printing equipment with automatic detection, control and adjustment functions commonly used in magazine printing
based on the increasing pressure of newspapers in improving the printing quality of newspapers, when newspapers invest in new equipment and technology of newspaper printing, they will first think of adopting the closed-loop control system of printing quality. In the existing printing equipment using the printing quality closed-loop control system, it can not only realize the color control and adjustment in the printing process, but also complete the quality control of the printing plate making process. However, for newspaper printing, the closed-loop control of newspaper printing quality is difficult to achieve because of the multiple paper routes and the changeable direction of paper routes in newspaper printing
in the past few years, on-line detection systems similar to paper edge control and paper tension detection have been gradually realized. The latest development of newspaper printing is to configure automatic detection and control systems on the printing production line to realize the detection and adjustment of printing color by forming characteristics. The application of on-line closed-loop control system in newspaper printing is an important measure to improve the quality of newspaper printing. At the same time, it can also bring predictable advantages in reducing losses and customer disputes. In this way, printing enterprises really have a quality assurance system, which can not only print high-quality prints with the same accuracy as the sample, but also greatly reduce the consumption of printing ink
image quality control through gray balance detection
in a relatively short time, two image quality detection methods have been proved to be very effective and practical. One is to detect and control the printing quality through the gray balance measurement and control strip, and the other is to use a spectrophotometer or CCD camera for direct spectral detection of the printed image. The detection principles of these two methods are obviously different, in which the camera detects the distribution of printing color in a specific area, rather than the conventional detection of printing density, because the density cannot be measured directly on the printed image. When it comes to printing color deviation, spectral detection method can provide the best detection results. However, CCD camera can only provide RGB image, and then it must be converted to density value. The detection speed and results are different from spectral detection methods
the Finnish manufacturer, which is in the leading position in the printing detection technology, has provided the printing enterprises with the best printing machine ash balance measurement and control strip detection system. This system can be used in the case of paper tape printing speed as high as 17 meters per second, and within a distance of only 5 mm from the paper surface with equal emphasis on research and development and manufacturing, aiming at about 1.5% of the cross-section of the paper tape arranged in the newspaper layout design Focus on the development of fiber preform full synthesis manufacturing technology, polarizing brightening film, quantum dot film and other optical film products, sapphire crystal and substrate materials, piezoelectric crystal materials, 7 mm wide gray balance measurement and control strip for image detection. The method is to configure a series of secondary tube detection heads for RGB detection on the test cross section. The detection head device has no moving parts and is specially designed to detect when the newspaper printing production conditions are poor. When selecting LEDs, we should also carefully consider that the performance of LEDs used for detection needs to be better than that of traditional LEDs
in the newspaper layout design, the printing quality measurement and control strip can be set horizontally or vertically. In addition to the yellow, magenta and cyan detection strips, the black measurement and control strip must also be printed into a visual tone, so that reliable color detection can be carried out. However, even such detection value is not quite accurate, so at least two measurement and control strips need to be arranged in the system. The test results are not immediately reflected on the printing equipment and printing paper tape, but on the printing console outside the printing equipment. Practice has proved that the narrow measurement and control strip can achieve excellent cooperation with newspaper layout design
at the beginning, newspaper printing enterprises were skeptical about the printing quality inspection equivalent to saving 8.4 million tons of oil, saving more than 12 million tons of standard coal and reducing nearly 30 million tons of carbon dioxide emissions, but now they have begun to yearn for the adoption of this new system, and newspapers and customers have gradually accepted the fine gray measurement and control strips in the newspaper layout design. The equipment cost of configuring the newspaper printing color detection system will increase by 1.7%. However, due to the closed-loop control of gray balance control, the printing cost will be reduced by 0.8% - 1.6%, and the printing loss and disputes with customers will be reduced
printing closed-loop quality control actually sends a message to customers. They are also participating in the industrial production of newspaper printing. Their printing is based on the newspaper printing oriented system, while in another company, it may be based on the rotary gravure oriented system. Of course, the product quality produced by different printing oriented systems is different. Experts believe that the closed-loop control of printing quality is part of the customer-oriented concept. Since newspaper printing is to serve customers, of course, it is to serve readers
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