Corrugated box is a kind of ordinary paper packaging product which is inseparable from our life and production. The printing quality of corrugated box is not only related to the appearance quality of corrugated box, but also affects the sales prospect of the packaged product and the image of the product manufacturing enterprise. Therefore, it is especially important to analyze the problems of how to improve the surface printing effect of corrugated boxes, how to choose a suitable printing process, and further reduce the processing costs of cartons. Chengdu Yabo Printing will discuss these aspects here. 1. Corrugated cardboard processing technology Corrugated cardboard processing technology is mainly divided into two categories 1. Production process of automatic corrugated cardboard production line The corrugated cardboard production process is widely used, with the advantages of large production batch, large carton forming volume, good corrugated quality and so on. Corrugated paperboard produced by this process is usually made into cartons through water-based printing, grooving, gluing, forming and other processes. The carton produced by this process is mainly used for transport packaging. 2. Production process of semi-automatic corrugated board production line The production process of corrugated paperboard is to print face paper first, and then laminate it with corrugated core paper and paperboard. Corrugated paperboard produced by this process is usually made into boxes by die-cutting, creasing, and nailing. The carton produced by this process has good molding quality and good surface treatment effect. The carton produced by this process can be used as a sales package. 2. Conventional carton printing methods Conventional carton printing methods mainly include flexo, offset and screen printing 1. Flexo printing Corrugated box The conventional flexographic printing corrugated box process is to print directly on corrugated cardboard, using water-based ink, so some people call this process watermarking. Flexographic direct printing has the following characteristics: (1) Large format. The widest flexographic printing machine can reach a maximum width of 2.5m ~ 2.8m. (2) Low price. The flexographic printing plate has high durability and can be reused; the ink price is also low. (3) It can be linked to production, such as printing, slotting, creasing, ordering (sticking) boxes, bundling, etc. can be completed in one machine. (4) There is relatively little reduction in the strength of the carton. Because flexo printing is light pressure printing, it has little effect on the strength of corrugated cardboard. (5) The printing accuracy is not high. The number of screen lines for conventional offset printing is 175 lines / inch, and the number of screen lines for flexographic printing cartons is 35 lines / inch ~ 65 lines / inch. Although the printing quality of four-color images has improved in recent years, there are still limitations. (6) The plate making is easy or difficult, the text line draft is easy to make, and the four-color image making is more difficult. (7) The stability of the printing quality is not good, which is mainly reflected in the difficulty of controlling the color depth of the printing ink. The flexographic direct printing process is suitable for the first type of carton production process, which is currently widely used in carton factories in China. 2. Offset printing Corrugated carton The conventional offset printing corrugated carton uses indirect printing, that is, the carton facial paper is printed first, and then the printed facial paper is mounted on the corrugated cardboard. Because the resolution of the PS version is relatively high, very fine print patterns can be printed. At present, most of the high-end corrugated boxes used for sales and packaging in China are offset printing products. Corrugated cardboard boxes with offset printing have the following characteristics: (1) It is not suitable for the use of cardboard linkage production line, only suitable for single-sided corrugated machine, and the production efficiency is low. (2) The format is limited, generally smaller than that of flexo carton. (3) The printed products are very fine, the number of screen lines can reach 150 lines / inch ~ 200 lines / inch. (4) The plate making is easy, and it is the conventional plate making of PS version. (5) Surface finishing, such as coating and glazing. (6) High printing cost. (7) The printing quality is relatively stable. 3. Screen-printed corrugated cardboard box The screen printing corrugated box process uses direct printing. Since the ink drop rate of the screen is proportional to the hole distance of the screen, the resolution of screen printing is not high, and the image accuracy is low. The number of conventional screen lines is 60 lines / inch to 80 lines / inch. The screen printing corrugated box has the following characteristics: (1) It is not suitable for linkage production line, and the production efficiency is low. (2) The printing format can be large or small. (3) Printing can be completed before mounting and boxing, or after mounting and boxing. (4) Suitable for printing non-fine products. The ink color of screen printing is thick, so its color saturation is high and the visual effect is strong, especially the spot color printing is better on the spot and the effect is better. (5) The plate making is easy, and the plate making cost is low. (6) Low printing cost. (7) The printing quality is relatively stable. Zhejiang Hisun Electrical Appliance Co.,Ltd , https://www.cn-hisun.com