Talk about the printing of corrugated boxes

In order to adapt to changes in the market economy and enhance the competitiveness of products, many corrugated carton layouts have begun to use dot pattern to highlight products. Rich layout, but also improve the packaging quality of the product. In terms of packaging design, the graphic expression and visual impact are strong and can easily attract people's attention. The use of dot-printed graphics is difficult to counterfeit, and the anti-counterfeiting performance is good, rich in sense of hierarchy, three-dimensional, and pleasing to the eye. In order to obtain high-quality dot effect, we must first work hard on the draft: For corrugated box printing, too dense dots can easily cause stencil printing; if the dot is too thin, it will lose graphical details and affect the graphics effect. . The graphics are divided into vector and bitmap, and their dot processing methods are different. For vector diagrams, grayscale is controlled, gray levels are used to represent levels, and the size of grayscale determines dot size and thinness. Handle the scanned image. When it is full, it is converted to grayscale mode, and then processed by the color halfone in the Pixelate filter in PHOTOSHOP. The size of the dot is adjusted according to the graphic gray level through the parameters in the color halfone dialog box, and the dot pattern suitable for printing conditions is obtained. After the vector image and bitmap are processed, the output center must output the negative film for printing. The number of output network lines also determines the important parameters of the graphic network points. The larger the number of network lines, the more the network points, and the output must be selected properly. The number of network lines. In the process of making dot patterns, we must consider the number of grayscale graphics and output lines of vector graphics, as well as the halftone processing graphics of the bitmap and the number of output net lines, in order to obtain the overall net-shaped effect. Under normal circumstances, as much as possible to avoid the printing of dot pattern and large area color pattern in the same block, if large area color pattern and dot pattern are separately printed, pressure adjustment and color control are much simpler. After the design draft has been output as a negative film, it can be plated. The resin plate used to make the dot pattern requires a high hardness of 45. -50. Shore A is suitable, and the material with low elasticity and slow recovery of denaturation can better ensure the reproducibility of the dot pattern. The production of resin screens on the same product packaging should be carried out as much as possible at one time. It is extremely easy to see differences in shades of printing at different points in time and produce different results. If the dot version cannot be processed at one time, the back-exposure, main exposure, rinse, drying, de-sticking, and post-processing time must be strictly controlled during the process of plate making, so that each processing data is consistent to obtain the same effect of the dot resin version. When designing dot patterns, it is also important to consider the number of screen lines of the anilox roller in the company's printing press. Correct selection of anilox rollers is very important and determines success or failure. The plating roller is the most common type. With the widespread use of back-scraping blades and the promotion of new high-speed printing presses, rapid wear of the anilox roller is a problem. Many companies have started to use ceramic ink rollers with wear resistance. Its grace is good for dot printing. When the same color printing contains full plates and dots, the thickness of the full plate portion can be increased by 0.15-0.30 mm to improve the plate pressure and the printing pressure. There will be dot gain during printing, which requires the printer to adjust the pressure as little as possible to obtain the smallest dot gain, and to make detailed records of the adjustment parameters of the printing press so that the same printing effect can be traced later. After printing, it is necessary to immediately clean the dot resin plate to prevent the ink from drying on the plate, resulting in clogging of the dots, resulting in a bad plate.