Commercial rotary presses have a fast printing speed, and before they reach the normal ink color and registration, there will be a lot of scrap and defective products. In order to improve work efficiency, as soon as possible qualified printed matter, to reduce the unnecessary waste of ink, paper, etc., prepress production should use the printing plate scan, the color difference between the print and the design is controlled within the minimum range. Plate scanning can reach 80% of the normal ink required for printing, and through the adjustment of the overall ink characteristic curve, it can quickly produce genuine products, greatly improving work efficiency, and is especially important for those printing jobs without proofing. . Plate scanning work is more effective for those short-printing proofs that have proofing. It greatly shortens the time for commercial printers to print normal ink, saves a lot of raw materials such as paper and ink, and reduces costs for enterprises. If you encounter the situation where the scanned curve is different from the normal ink used in the actual printing, the following aspects must be checked before printing: Secondly, check whether the smoothness of the plate used is satisfactory. Sometimes the plate has dents, the surface is uneven, and the scan results are also affected. The flatness of general domestic printing plates is slightly inferior to the imported foreign versions. By adjusting the inhalation volume of the plate scanner, the effect of plate unevenness is reduced. Generally, when the imported media is scanned, the inhalation volume level is selected to be one level, and when the domestically produced media is scanned, the inhalation volume of the second or third stage can be selected, and the screen can be used flexibly depending on the leveling condition of the printing plate. After increasing the intake volume, the printing plate is more evenly adsorbed on the scanning panel, which is conducive to correctly reflecting the ink demand of the graphic portion of the printing plate. However, blindly increasing the amount of inhalation may also attract a large amount of dust. Over time, it will block the suction hole and affect the scanning quality. In short, prepress production should gradually realize that: prepress production to adapt to commercial rotation printing, can not be used in commercial rotation printing to adapt to prepress production. The pre-press production of commercial rotation printing is complex, and it is necessary to continuously explore and summarize the actual work in order to continuously improve the production level.
First of all, see whether the width of the long red film on the edge of the film is correct. The width of the red film is different for different models. For example, the roller with a circumference of 598mm for the M-600 in Heidelberg requires a red film width of 23mm, while the M-600 has a circumference of 578mm. The drum requirement is 23.1mm, and the greater the difference from the actual required width, the greater the impact on the scan results. Therefore, in actual operation, it is necessary to combine the used model with a suitable width of the solid block through the red film.
Source: China Desktop Technology
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