In the past, the main function of corrugated boxes was as a transport package, and the surface printing was also very simple. The reason is as follows: First, the carton factory and users do not attach importance to the packaging design of corrugated boxes, and only use the carton as a tool to protect and hold the products. Second, the flatness of corrugated boxes is relatively poor, making it difficult to print exquisite designs; Previous print editions were all hand-printed and could not reproduce the fine lines and dots. Of course, there are also a few printing units and other reasons, which have limited the rapid development of carton printing.
In recent years, with the rapid economic development and increasing exchanges with foreign countries, people are increasingly aware of the importance of packaging and decorating, especially the influx of international supermarkets such as Wal-Mart and Carrefour, and the increasing number of domestic supermarkets. People have changed the traditional shopping habits. At the same time, the sales function of corrugated cartons has become increasingly prominent. Users have increasingly valued the outermost packaging of cartons, the display products and the company's image. At the same time, the universal application of flexographic printing plates (photosensitive resin plates) and the rise of flexographic prepress technology have also given strong support for carton printing.
In the field of packaging design, past color packaging or exquisite packaging designs are mostly achieved through offset printing and gravure printing. Offset printing and gravure printing are mature printing methods. There is still a lot of printability that designers need to pay attention to when designing packaging. Flexo printing is a new printing method. To truly reproduce the designer's packaging design, designers need to Flexography features to learn more. In the prepress design for direct flexo printing of corrugated boxes, designers must pay attention to the following points.
First, a clear expression of the color number of creativity
Daqian world, colorful, especially the designer's eyes, is also good at discovering beautiful colors, and organically organize them together to create a variety of or elegant, or bold, or warm, or have a strong visual impact works. As a packaging design, the ultimate goal is to achieve its own creative results after printing, and to achieve industrial production. Therefore, for the packaging design of corrugated cartons directly flexo printing, in the use of color, we must first understand their own creativity in a few color printing machine to achieve, clear their own ideas through a few colors to express. The number of domestic corrugated cartons flexo printing presses is generally 2, 3, 4, and 6. Before confirming several colors, on the one hand, it is necessary to take into consideration the number of color groups on the printing press, and on the other hand, it must be considered whether the white ink is used or the lacquer is used in the process, so as to finally determine the number of colors that can be used to express the idea.
Of course, under the premise that the same can fully express the design creativity, the number of printing colors should be reduced as much as possible, which is beneficial for the printing operation, quality control, and cost control in mass production.
In addition, there are also many manufacturers who wish to use as many spot colors as possible in order to achieve the uniform color of each batch of products and to play a certain anti-counterfeiting effect. Thus, in addition to the traditional CMYK4 color, its packaging uses spot color inks. However, in actual operation, due to limitations of printing machines, manuscripts that need to be printed on a four-color machine do not show up in any of the four colors at the time of color separation. In the end, they have to communicate with the designer, and the colors are similar to each other. Or make changes to the designer's work.
Because the flexographic printing is transmitted through the anilox roller, the number of the anilox roller determines the amount of ink transferred and the fineness of printing. Normal screen adjustments use high-line anilox rollers to make the dots clear; while field versions use low-number anilox rollers to achieve color saturation. In a color, there are both halftone images, and on the ground, and when they are visually prominent, this color is generally divided into a halftone edition and a field edition separately to facilitate the printing operation. Therefore, when considering the overall color number in the design process, do not ignore this feature of color separation in flexo printing.
In addition, it is often encountered in practice that many corrugated box printers are three-color machines and cannot achieve normal four-color printing. Therefore, in the process of watermarking a corrugated cardboard box, three colors are often used. Reproduce four-color manuscripts. There are two actual situations to consider when producing black with three-color overprint:
(1) ink color cast to produce non-standard black three-color overprint;
(2) Three-color overprinting can make the ink layer too thick, affecting the printing quality and effect.
For the above two cases, the designer needs to understand the condition of the ink when processing the packaging product printed with the tricolor machine. Some printers use the ink color cast to properly consider reducing the color intensity of the selected color. Some articles may not necessarily remove the black version. For example, the reproduction of the food can eliminate the cyan version, and the reproduction of the tree can remove the red version. This maximizes the original style and hierarchy. If the problem of printing color number is taken into consideration at the time of design, the above difficulties will not be encountered before mass production. For example, when we dealt with the design of Tsingtao beer cartons, we took into consideration the fact that we had to implement it through three-color printing presses. Therefore, the watermark color printing process of corrugated cartons was successfully implemented and was promoted in the market.
(to be continued)