The future development direction of color box printing process

The development of market economy has greatly enriched commodity trade and increased export products. As the most widely used form of product transportation and packaging, the color box has changed from the original single text line printing to the color high-quality sales packaging. As an important process of the color box after the process, printing has become a production link that enterprises pay more and more attention.
1. Introduction of color box printing method
At present, China's color box printing a variety of ways, the traditional offset printing, flexographic printing, screen printing and in recent years the rise of flexographic pre-printing, gravure pre-printing, digital printing methods have occupied their respective markets. Each method has its own advantages and disadvantages and the scope of printing. Enterprises should choose correctly according to the actual production and product characteristics.
2. Offset printing process of color box
Offset printing is currently the most mature printing technology, occupies the first place in the packaging printing. The graphic part and the blank part on the printing plate have no difference between high and low, and are almost on the same plane. When printing, water is applied to the printing plate first, and then ink is supplied to the printing plate, thus printing is realized by using the principle of ink repulsion. Its plate-making process is simple, low cost, high production efficiency, exquisite patterns and stable quality. However, offset printing is not suitable for joint line production and has low efficiency.
There are two main ways to use offset printing, one is to print directly on the cardboard, and the other is to print the face paper first, and then mount the face paper. Among them, the indirect printing method is the pre-printing of a single sheet of paper, and its printing quality is high. After printing, it can also be used for surface decoration such as polishing and laminating, which can greatly improve the appearance of the color box. It has always occupied a major position in the sales and packaging of high-end products. But the mounting processing efficiency is low. The direct printing method is mainly aimed at micro corrugated products, which is widely used in foreign markets and is relatively mature. The improved offset printing machine can be used in production, such as Roland 900 large-format printing machine can be competent for direct printing of corrugated board. This printing method can effectively ensure the formability of the color box under the condition of losing the strength of the limited cardboard, and can realize the exquisite printing effect. However, the cost of equipment input is still relatively high.
3, the color box of the flexographic printing process.
Flexographic printing is a short ink path direct printing method. The plate material is made of a certain elastic feeling resin, the graphic part is convex, the blank part is concave, the ink supply device is used for scraping knife and anilox roller, and the water-based ink of environmental protection is used for production. There are two kinds of printing methods for color boxes: direct cardboard printing and pre-printed face paper before mounting. Direct printing can be linked production, currently in the middle and low color box production is the most widely used.
Flexographic printing machines mainly have two types: organic group type and satellite type, with large printing format, many colors, relatively high quality and low cost. Wide format with flexo printing equipment can print 2.5~2.8 meters in width. Flexographic printing is a light pressure printing method, the strength loss of corrugated board is small, and the water-based ink meets the requirements of environmental protection. The weakness of flexographic printing is that its printing plate is easy to be deformed under pressure, and the dot expansion is difficult to control. The dot in the highlight part of the image is easy to lose or increase seriously. In the dark part, the dot will be expanded and merged into a real state at about 85%, thus resulting in a small range of tone replication, only about 5% ~ 85%. It is difficult to achieve the desired effect for high-grade printed matter with rich levels. In addition, due to the current printing ink and surface treatment of printing materials, the actual production speed is only about 100 meters to 300 meters. With the progress of flexo printing technology, the quality of water-based ink continues to improve, adhesion, tinting power continues to increase, the use of closed scraping knife system can also better ensure the transfer effect of ink, flexo plate printing speed and quality will be greatly improved.
4. Pre-printing method of color box
At present, there are two main ways of pre-printing: flexographic pre-printing and gravure pre-printing, and gravure pre-printing is the main way. The process is to first use gravure or flexographic printing web, rewind and then tile line mounted to become corrugated cardboard, and finally die-cut to get the color box technology. The problem of pattern alignment should be considered when the pre-printed tissue paper is mounted. Generally, a photoelectric tracking control system is installed on the cross-cutting knife to achieve accurate cutting at the pattern. Compared with printed cardboard, pre-printing can provide more exquisite products, and the printing quality is more stable and reliable, and the quality of the color box is better. From the point of view of production efficiency, the use of web printing can achieve non-stop paper change operation, which is particularly suitable for color box products with large quantity and high printing quality requirements.
To adapt to the high speed of pre-printing production, the use of printing inks and paper materials also have higher requirements, such as the smoothness of the paper is better, its edge pressure strength and resistance to breaking performance to good. Practice has proved that although coated white board paper has a good color expression, but in the process of high temperature drying, the color will change, affecting the pattern effect; hanging pulp white board paper, its surface smoothness is poor, the quality of the printing dot image is poor, while the ink consumption is large, it is not the most ideal preprinted paper. The white cardboard, its smoothness is high, printing dot image quality is good, but also can withstand the test of corrugated high temperature baking channel bonding process, is the ideal pre-printing paper.
5. The intaglio pre-printing process of the color box
Gravure printing is also a direct printing method with short ink paths. The graphic part on the printing plate is concave, and the thickness of the ink layer is used to express the gradation of the image. Its products have the characteristics of thick ink layer, full, bright color, strong three-dimensional sense, high clarity and gloss, which has great advantages for the printing of high-end products. The gravure equipment for color box preprinting is mainly a large unit type printing machine, and is equipped with a computer cross-cutting and slitting machine with photoelectric detection function to meet the requirements of cross-cutting accuracy when mounting. The installation of the base paper preheating device and humidifier on the production line can effectively adjust the moisture content of the base paper, ensure the stability of the tension, and reduce the wrinkling of the base paper during paper supply and affect the subsequent production and processing. The use of dust removal and explosion-proof electrostatic ink absorption device, PLC computer correction device, automatic printing registration device, and the application of automatic image detection device provide guarantee for the printing production of high-quality products. But also can print glaze a complete, improve the product grade.
At present, the printing plate for intaglio is mainly produced by electronic engraving technology, which greatly reduces the cycle, but the cost is still high. Although the price of domestic equipment is cheaper than imported equipment, the equipment is complex and the cost input is still large.
6. Digital printing process of color box
The application of digital printing is another development direction of color box printing, which can make graphic information directly from the computer to the surface of the paper, eliminating the need for intermediate plate making and other links. Moreover, digital variable information can be printed, which can make the contents of each sheet different and even the materials can be changed. On-demand, timeliness, and variability are the characteristics of digital printing. But the printing quality is at least equivalent to the traditional printing technology, much higher than the printing technology. The investment cost of a general digital printing machine can be 40%-50% lower than that of traditional offset printing or flexo printing. Compared with traditional printing, its printing speed is faster, the cost per page is lower, and it has a competitive advantage. Among various digital printing methods, inkjet digital printing equipment has developed rapidly.
Digital printing is a development direction of on-demand printing in the future, but compared with a large number of industrial packaging, the printing speed, format and other aspects need to be improved. However, with the continuous development of personalized, short version of a small number of products, such as corrugated cardboard display stands, small trial packaging production, digital printing will occupy a dominant position in this field.
7, the future development of color box printing process
Color boxes are constantly transitioning to sales packaging, which requires the printing quality of their products to be higher and higher. Of course, the requirements of green printing make them colorful and meet the requirements of green environmental protection. This puts forward higher requirements for printing equipment and auxiliary materials for printing. In addition, the development and application of new color box products, such as miniature color boxes, heavy-duty color boxes, corrugated extended products, etc., have different characteristics, and the printing process has also improved the corresponding requirements. In the choice of printing methods, for a long period of time, various printing methods will exist at the same time. In the long run, the pre-printing process has a high printing quality and effect, avoiding the impact of printing on the strength of the cardboard. From the efficiency point of view, and tile line linkage production, can greatly shorten the production cycle, to meet the customer's timely supply requirements. For high-quality, high-volume product production, pre-printing is undoubtedly the best way.
To improve the quality of color boxes, we must pay attention to the development of post-processing. To meet the market demand, the printing quality must be continuously improved. There are many factors involved in printing and processing. Plates, equipment, ink, paper, environment, and operations must be strictly controlled. All processes must be closely coordinated to reduce production failures and increase corporate profits. Of course, all enterprises should also recognize the development situation of the industry, actively carry out reasonable upgrading and transformation of equipment technology, and constantly improve their competitiveness.