First, the main advantages of offset printing are: printing processes and equipment have been developed very well. The supporting raw and auxiliary materials have also been fully matured. The printing quality is good and the cost is low. Has been accepted by domestic and foreign printing companies. At present, offset printing accounts for more than half of the total printing volume in foreign countries; in China, books, newspapers, and newspapers have almost been offset by 100%. More than 800 offset presses have been introduced in packaging printing. Many companies have not only increased a lot of offset presses, but also introduced multi-color offset presses with advanced world standards. Offset printing has also accounted for about 60%. Offset printing also plays a dominant role in the packaging field. Regardless of domestic and foreign countries, the proportion of offset printing may decrease for a long time, but its dominant position will not change.
Offset printing is mainly used for the printing of paper-based materials. Printing on plastic film has many limitations. Sheet-fed offset presses can be changed in print format and are flexible. At present, most web offset presses have a fixed print format. Its application is limited. With the development of technology, web offset presses are also constantly improving. Now we have successfully developed a web offset press that can change the printing format. At the same time, we have successfully developed a seamless roller web offset press. The printing cylinder of this web offset printing machine is seamless and in this respect has been the same as a web gravure printing machine.
Offset presses are also constantly improving their printing capabilities. The corrugated board can be printed with improved and retrofitted parts. UV printers can be printed with improved UV dryers. The above improvements continue to expand the use of offset presses in the field of packaging and printing. Offset printing inks will soon be put into practical use, which is an improvement for offset printing.
Second, the gravure gravure printing, ink full three-dimensional, in a variety of printing methods, the printing quality is the best, and the printing quality is stable, the printing plate long life, suitable for a large number of large-scale printing. Gravure can print the material of the book, such as a plastic film. However, gravure platemaking is complicated and expensive, and its benzene-containing ink pollutes the environment. These two problems have affected the development of gravure printing. In particular, the reduction of a large number of large-scale prints, the short version also requires a large number of low-cost prints, so that gravure will continue to lose the market. Domestic and foreign experts all believe that the proportion of gravure printing in the printing field will decrease year by year, even in the field of packaging and printing.
In the flexible packaging printing market in the United States, gravure only accounts for 10% and is declining. In China's flexible packaging printing and printing of cigarette packs, gravure printing occupies an important position. More than 200 sets of gravure printing presses have been introduced, and in some regions too many gravure printing presses have been introduced, resulting in excess production capacity, which was formed under the special circumstances of our country.
Due to advances in technology, gravure printing machines are constantly improving. The application of gravure printing plate computer-to-plate (CTP) and the gradual promotion of gravure printing ink have gradually solved two major problems of the gravure printing process. With the resolution of the gravure problem, whether or not to reverse the declining trend of the gravure printing process remains to be tested in practice.
Third, flexo printing (a) the main advantages of flexo 1, a simple device structure, easy to form a production line. In flexographic, gravure, flexo, and other printing equipment, the flexo press is the simplest structure. As a result, the price of flexo presses is relatively low, and printers invest less in equipment. At present, most of the flexo presses are combined with bronzing, glazing, cutting, slitting, die cutting, indentation, punching, and windowing processes to create a production line that greatly increases labor productivity.
2, a wide range of applications and substrates. Flexo can print almost all prints and use all substrates. In particular, corrugated printing in packaging printing has its own unique features.
3, extensive use of water-based ink. Offset, gravure. Among the three printing methods of flexo printing, only Flexo India currently uses water-based inks. Non-toxic, non-polluting, favorable for environmental protection, especially suitable for packaging and printing.
4, the lower cost. The low cost of flexo printing has formed a wide range of consensus in foreign countries, and there are disputes in the country. The main reason is that most flexographic printing machines, flexo printing plates and flexo printing inks used in domestic flexo printing are imported, resulting in a lower cost. high. Offset printing and gravure printing are relatively inexpensive in this regard. With the local production of flexographic equipment, its plates and raw materials, its cost will gradually decrease. (To be continued)