Keep a good printing process and operating technology (a)

Flexo printing is one of the four major printing processes in China. It is compatible with the advantages of letterpress, lithographic, and gravure printing processes. It has the advantages of convenient operation, short production cycle, clear product marking, light printing pressure, high printing plate printing rate, and stable product quality. The good advantages. The flexographic printing process can not only print substrates with good surface glossiness, but also can print rough surface materials; it can print non-absorbent substrates and can print a variety of materials with strong absorption; it can be used to print internal packaging. Products, but also print packaging cartons, cartons products. The good process characteristics of flexographic printing make it widely used in printing paper, paperboard, plastic film, cellophane, stickers and aluminized materials, etc. It is a production with wide market prospects for printing and packaging, commercial and other products. Process. However, as with other printing processes, the flexographic printing process inevitably causes some print quality problems and affects the quality of the product. One of the most common problems with print quality is the loss of dots, the enlargement of dots, the distortion of the printing plate size, and the print bar marks.

First, the issue of printing quality of flexographic printing outlets

Reticle version is a common product form of flexographic printing. In the printing production process, if the production process is not properly controlled, quality problems such as dot loss, deformation, and enlargement are prone to occur. For example, the small dot of the layout highlight area is easy to lose, and dark dot network parts It is prone to enlargement, affixing, and becoming real. Due to the expansion of outlets, the print layout lacks a sense of hierarchy, and the quality of printing is significantly reduced. The printing plate is soft and flexible, which is the main reason why the quality of the flexographic printing screens is prone to quality problems. Process analysis shows that in the flexographic printing process, under the effect of pressure, the graphic size of the printing plate becomes larger, so that the dot area becomes larger, and the fine dots are easily lost due to wear or uneven pressure. On the other hand, due to the flexographic printing, using a low-viscosity ink, when the contact pressure between the surface of the printing plate and the print is slightly larger, the ink on the printing plate will spread outward, making the ink layer in the middle of the expanded dot thinner. The edge of the ink layer is thick, forming a tired-like hollow point, with a magnifying glass to observe the edge of the dot visible paste, which is the basic characteristics of the flexographic printing dot increase. The production process also shows that the higher the dot number of the flexographic plate, the larger the dot gain; the coarser the ink particles used, the larger the dot enlargement; the larger the ink volume on the plate or the ink is too thin, and the dots are also enlarged. The larger the printing pressure and the pressure of the anilox roller, the larger the dot enlargement. The softer the substrate, the rubber roller, the pad or the flexible plate, the bigger the dot enlargement; the worse the accuracy of the machine is, and the dot gain is also larger. The bigger. In addition, the thickness of the printing plate is inconsistent and it is easy to make the printing dot enlarge or lose. Therefore, to prevent the emergence of flexographic printing quality problems, it is necessary to pay attention to good process technology and operation technology, but also to choose a good quality, high precision media, but also pay attention to good equipment maintenance, can be better Guarantee the printing quality of outlet products.