Combination printing

As the name implies, combined printing is a combination of multiple types of printing. The printing processes of different printing and post-press processing have been completed on the same production line. This is the way of printing (such as plastic film or other printing materials) to complete multiple printing processes.
Combination printing had existed for a long time. The meaning of the combination at the time was not as complicated as it was now. Sheet-fed printing machines had been coated with glazing and printing marks for a long time. To a certain extent, this was also considered as combination printing. . However, the complexity of today's combined printing makes such a simple combination printing pale, and now referred to as the combination printing, which no longer includes these simple "combination" printing.
Today's combination printing is mainly for the production of certain special products, such as lottery tickets, packaging of certain commodities, and for the purpose of processing, the purpose of anti-counterfeiting, and the requirements of printing products, there is a lack of new work and new technologies. . It is a combination of various printing processes and post-printing processes. It is an inevitable trend for the development of large-scale production and an inevitable requirement of the market. Due to the development of technology, the application of computers in the design and manufacture of printing machinery, and the realization of digital process flow, the combination printing has made great progress in recent years, and it has occupied a considerable proportion in the current printing applications.
I. Advantages of combination printing and application The combination of printing appearance and development conforms to some of the major trends in the development of printing. It is the need and common result of cooperation in many aspects such as technology, technology, machinery, electronics, and management science. These include:
1. The need for large-scale production. Combined printing has traditionally been printed or processed on different stand-alone machines. In the relatively backward technology development, it is necessary to deal with many technical problems, such as the beat rate and failure rate.
(1) Beats. Different printing processes have different processing speeds that can be achieved in a single machine. Some printing processes are simple and the speed of completion is fast. However, due to the complexity of the process or problems caused by material properties (such as ink drying), certain processes can be caused. Can not be processed at excessive speed. If you link together processes that have different speeds (that is, different beats), you will inevitably drag the legs of some simple processes and affect the productivity of the entire production line. However, in today's printing, in general, all machines that handle the same material can reach a certain speed limit that is limited by the material, so there is not much problem in achieving the beat.
(2) Failure rate. Faults are also a major problem that has plagued online production in the past. Due to the relatively high failure rate of stand-alone machines in the past, the time and frequency of single-process shutdowns are often one or more orders of magnitude higher compared to today's machinery and equipment. If it is a stand-alone production, the impact on the overall productivity is not great. If the machines with such a high failure rate are linked together, the faults in each step of the production process will come up one after another. As long as some of them go wrong, the entire production line will stop. This has a great impact on equipment utilization. As the failure rate of production stand-alone machines is greatly reduced, online production conditions are now available.
(3) The openness of the system. Online production is the result of many years of hard work by printing equipment suppliers. Similar to the development of the computer industry, the current printing equipment is also a considerable effort on the modular design, making the interconnection between different devices to reduce the very hurdles, such as the beat problem in the past by mechanical is not easy to achieve, now Electronic control is no longer a problem. Many equipment manufacturers are also designed to operate on the basis of other manufacturers' models, so compatibility with other models is one of the important design criteria of some smaller equipment. In addition, the modular design is not only an indicator to ensure the online operation of the machine, but also ensures that the machine can run off-line, which is the choice of the flexibility of the production process.
2. The need of printing process. Different printing processes have different printing characteristics, and these characteristics cannot be replaced by other printing processes in many occasions. Therefore, using different printing characteristics of different printing processes is also one of main purposes of combination printing. For example, some products require the low cost of offset printing. Some products require the ink thickness of screen printing. Some products require special printing materials (such as fluorescent inks, UV coatings, etc.). In order to meet these special needs, different requirements are required. Printing process for printing.
This of course also includes the post-printing process. In combination printing, it is often necessary to add some post-printing processes such as coating, hot stamping, die-cutting, marking, laminating, etc. in order to make the prints have a certain function. . These were achieved in the past after printing on a stand-alone machine and are now done directly on the production line.
3. Anti-counterfeiting needs. Combination printing was first used in the printing of banknotes, securities, and lottery securities. For example, the printing of banknotes has been preceded by engraving of gravure with techniques such as typography and embossing. The use of the characteristics of different printing processes on a printed matter increases the difficulty of counterfeiting and increases the level of anti-counterfeiting.
4. The need for printing products. This is mainly reflected in packaged prints and special prints. This kind of product has many special requirements. In addition to the common bronzing, glazing, and marking, there are some die-cutting, indentation, embossing, etc., as well as variable data printing with new technologies (this type of printing is mainly Inkjet system to complete).
In packaging printing, the combination printing is mostly connected to the back end of the production of the packaging product. In such a linkage, the printing and post-press processing is only a foil. In a huge packaging production line, adding a few printing processes can not be regarded as excessive requirements, so the combination printing is also a matter of course. Although the combination printing is not obvious in such a field, it is a combination of high technical requirements from the printing point of view.
5. The need for management. The management of printing production is now fully computerized. On-line production is the need of printing and processing plants. It is to improve the management level, reduce the labor force, reduce the inventory of semi-finished products, and shorten the printing cycle. (One pass can complete multiple processes of the product.) The need for such, as well as some additional advantages, such as accurate overprinting, waste reduction and so on.
6. The need to print a single product. The unity of producing products is also a reason for the rapid development of combination printing. The printing industry currently seems to be taking two extremes. One is that more and more short-lived versions require more and more printers to be able to cope with the needs of different printing processes. That is, printing companies need to have multifaceted functions; on the other hand, due to the market structure Adjustment, production of a single product can form an advantage in a small production environment, so online, large-scale, specialized is the need of enterprises with large production needs and a single species, using a single machine to produce a relatively fixed number of large production The products, such as bill production, bank savings, etc., are one of the main application areas of combination printing.
Second, the combination of printing process problems Combination printing is a printing process that combines different printing processes, so the combined printing in the technical implementation of the problem is mainly the process before and after the arrangements. This generally follows the order of arrangement during stand-alone machining, such as printing before printing and then printing. This may seem simple, but it is difficult to achieve. It is very knowledgeable in specific arrangements. It depends to a great extent on experience and some printing materials used in production (such as paper and ink). .
1. Printability on printed materials. Refers to the use of paper, plastic film, ink and other materials compatibility issues, mainly mutual coverage and attachment capabilities. Due to the interaction of these materials in a short period of time (one paper feed), the compatibility between them may cause many problems.
(1) Ink. The printing suitability of inks used in different printing processes is quite different from that of substrates such as paper. The inks used in different printing processes have very different indexes such as adhesion, drying speed, etc. Therefore, different analysis should be made according to different situations. This is somewhat similar to the previous debate about wet-damp printing: In the past, when the drying speed of printing inks was not yet able to adapt to the speed of the printing press, when the wet ink was imprinted on the last-colored ink, it would cause anti-sticking or printing. The problem is caused by the inaccurate amount of ink being printed, thereby affecting the reproduction of duplicated colors. In the combination printing, what we need to consider is no longer the mutual covering performance of the different printing inks of the same printing process, but the mutual coverage of the inks used in different printing processes, that is, to consider the consistency of different printing inks. Transparency, hiding power, and adhesion affect the printing process and product.
In terms of ink coverage, the opacity of screen-printed inks is often much greater than that of plain inks. Which type of ink is first printed is a requirement in the design of prints and a requirement in the printing process. If offset printing is first followed by silk screen printing, the screen printing ink completely covers the graphics of the offset printing section. If, in turn, the offset printing image cannot cover the printed graphics of the screen, etc., these need to be designed during the printing process. Think about it all.
Combination printing also includes the content of post-press processing, and ink compatibility and post-press processing compatibility also need to be considered. For example, if bronzing and then printing, then the osmotic drying type ink can not penetrate into the paper fiber inside and dry, the degree of drying on the metal foil surface and the adhesion between the metal foil will affect the next process Even the use of the product. The degree of resistance of the ink to post-processing also requires attention, such as the scratch resistance of the ink before and after the decision factors.
(2) Substrates. Combination printing is usually used in some special printing departments, such as packaging printing, securities printing, etc. The substrates used are often not as single as commercial printing, and only offset and coated paper. Combining printing is about printing materials that can be imagined. Apart from ordinary paper, there are paperboards, cardboards, plastic films, plastics, glass, rubber, and so on, which are almost all inclusive. The printing suitability of different substrates is very different. The compatibility of different substrates for different printing processes and different inks is an important aspect that needs to be considered. Different analyses should be made according to different situations.
From the printing materials, the absorption of the material, gloss, and the degree of resistance to temperature, etc., are the main considerations for the arrangement before and after the production process. For materials with high ink absorption, printing processes that are not afraid of absorption are often carried out before printing processes that are afraid of absorption. For example, a flexographic printing is used to perform a primer printing and then an ink jet printing. If this process is reversed, the jetted ink is quickly absorbed and the quality of the product cannot be guaranteed.
2. The realization and adjustment of combination printing. The combined printing production models are generally designed and installed by the printing equipment manufacturers, and the manufacturers are also designed according to the needs of the printing and packaging processing factories. Therefore, some major problems have been solved by the manufacturers. However, the current trend in the production of equipment that is modular and modular is such that the person who implements combined printing is transferred from the manufacturer to the system integrator, and even to the printing and packaging manufacturer himself. The system integrators appearing to adapt to this situation are relatively new types of commercial organizations. Unlike ordinary commercial organizations, they not only engage in the wholesale and resale of goods, but also include the design of printing processes, the selection of equipment, and the adjustment of integration. Work in many ways. The design of printing and packaging manufacturers relying on system integrators to complete the combination printing is a key link in realizing the combined printing process.
In order to adapt to this change in situation, printing system integrators need to understand the needs of various aspects, not only to understand the performance of various manufacturers' production equipment and their compatibility, but also to understand the requirements of the end user of the machine and even the end user of the product. In order to achieve the perfect combination of design, composition and unity of printing. Printing system integrators have done a lot of work in this area and also have rich experience, which is an indispensable link in the current equipment selection.
(1) Selection of equipment. The production of printing equipment tends to be specialized, and different manufacturers only produce a single model with a certain degree of standardization. The larger printing press manufacturers and printing system integrators are integrated and systemized, and large-scale printing machinery, Some of the production linkage