Packaging is the continuation of the production process of commodities in the circulation process, and is an indispensable condition for commodities to enter circulation and consumption. With the emergence of new technologies and new products, the packaging market will be further expanded. In a sense, packaging printing is a printing industry that never declines. There are many printing methods for packaging printing, and the more commonly used printing methods are as follows.
1. Flexo printing
Flexo printing is a direct printing method that uses a raised image printing plate with elasticity.
The main advantages of flexo printing are as follows.
a. The equipment structure is simple and easy to form a production line.
Among the three printing equipment of offset printing, gravure printing and flexo printing, the flexo printing machine has the simplest structure. Therefore, the price of the flexo printing machine is relatively low, and the investment in printing equipment is small. At the same time, because the equipment is simple, it is easy to use and operate, and it is easy to maintain. At present, most flexo printing machines are connected with processing technologies such as tonic, glazing, cutting, slitting, die cutting, creasing, perforating, and window opening to form a production line, which greatly improves labor productivity.
b. Wide range of applications and substrates.
Flexo printing can print almost all prints and use all substrates. Especially it is very effective for corrugated paper printing.
c. Water-based inks are widely used.
Among the three printing methods of offset, gravure, and flexo, only flexo currently uses water-based inks widely. This printing method is non-toxic and non-polluting, which is beneficial to environmental protection and is especially suitable for packaging printing.
2. Offset printing
Offset printing is mainly used for printing on paper-based materials, and there are many limitations if printing on plastic films. At present, the printing midplane of most of the roll paper offset presses is fixed, and its application is limited. With the development of technology, the roll paper offset printing machine is constantly improving. Now we have successfully developed a web offset printing machine that can change the picture in printing, and at the same time successfully developed a seamless roll offset printing machine. After improving and installing some parts, corrugated cardboard can be printed. Water-based inks for printing will soon enter practical applications, which is another major advancement in offset printing.
3. Gravure printing
The ink color of gravure printing is full and three-dimensional. Among various packaging printing methods, the printing quality is the best and the printing quality is stable. The gravure printing plate has a long life and is suitable for mass printing. Gravure printing can print extremely thin materials such as plastic films. However, gravure printing is complicated and expensive, and its benzene-containing ink will pollute the environment. These two issues have affected the development of gravure printing.