Development of web printing presses

Today's food packaging mostly uses soft packaging materials. These materials are generally in close proximity to or even in direct contact with food, which may affect the quality of the food. Therefore, it is required that food packaging manufacturers must provide assurance on the quality of food. Materials and commodities with the following characteristics cannot be used for food packaging: 1. Harm to human health; 2. Causes changes in the sensory properties of foods such as internal components or color, smell, and taste. As we all know, odor and food packaging is a very complex field, this article will focus on: odor identification and threshold; odor caused by the packaging material; residual solvent optimization and measurement methods and residual solvent estimates. Web printing presses are more compact, automated, and efficient. Today's web presses are larger, but not necessarily faster. These presses look more like an industrial machine than a technician's tool. However, the automation of web presses is higher and the equipment itself is more complex. It is certain that web presses will gradually be integrated with computer systems as part of a computer integrated system. Thermosetting web presses are more efficient but more expensive. However, when printing companies in the United States invest in equipment, they attach great importance to web printing presses and 40-inch wide, 10-color, sheet-fed, sheet-fed printing machines. Before the 1990s, web offset printing presses were in a state of backwardness, and now printers have begun to become interested in facing thermosetting web printing presses. This size web-fed press produces predominantly four-ply or split print products. Combining this device with a sheet-fed press can create a very dynamic situation in a printing press produced by a sheet-fed press. Production Environment. Don't overlook the narrow web or small web presses in web presses. The small size of this type of press is generally less than 26 inches wide. In the most common case, these web presses range from 18 inches to 20.5 inches in width. Some of the printers in this size range are used in direct mail and in the range of small and medium-sized commercial printing. This type of printer is thermoset and has good performance. The other type is a cold-setting printer with a blanket cylinder and iron roller pair up to 10 units. For printers who want to use a web press, the range of options available for this type of press is very wide. Moreover, they can also choose to improve the productivity of the improved options and the corresponding annex. In addition to size considerations, other features and control methods of web presses must also be considered when purchasing. As thermoset web machines have become a key component of the production system from stand-alone equipment. This phenomenon has been widely recognized under the promotion of manufacturers. The first printing press business model is that the manufacturer should design, produce, and integrate as many components and components of the printing system as possible. Manufacturers no longer only use the press itself as some of their key products, and do not consider the material handling equipment and press ancillary equipment associated with this press. Now they see the press as an integrated printing system from paper input to output. If you want to combine various components, is there a better way than the main manufacturer to process it before it is sold? Of course there is. As an example, part of the design and production of the printing press must be carried out during the production process. However, some of them can be determined based on the requirements of the user or the manufacturer of the auxiliary accessories of the alliance. The purpose of the final printing press is to obtain flexible, high-level production efficiency, and to integrate the entire printing system model from production to final product delivery. For a supplier, this business model is able to control the use of pre-press, plate-making, printing, binding and related sending hardware and software through a strict control software. This method is based on the "digital network production system" authorized by the Research & Engineering Council. Heidelberg's acquisitions, collaborations, and measures to combine publishing and web press operations have shown that they are working in this direction. For printer manufacturers, the second business model is to play a system integration role. In this scenario, the printer gave the printer the right to choose the printer accessories and all other parts of the production system. In the system integration section, the machine-to-machine communication can be implemented using the integrated CIP3 protocol developed by the International Collaboration for prepress, printing, and postpress. Proponents of this program claim that this will give printers a wider range of device choices and also stimulate technology and price competition. The printer needs and wants to be selective about the device. It is very clear that in the market of web presses, the press itself will continue to be a more integrated production equipment under digital control. At least in a short period of time, these two business models will develop side by side. However, from the previous period, economic development may lead to the further merger of printer accessories and component manufacturers. Perhaps this change involves all production of printing production equipment and software. the company. Whether it is a basic web offset printing platform or a component integrated in a computer-integrated production system, this large production process in the printing industry is undergoing tremendous changes. For many years, Heidelberg has been committed to the production of full-web presses. By 1993, the Heidelberg web printing system changed the web production model by introducing the six-color, double-sided M3000 shaftless, seamless blanket cylinder press. With wide web presses operating at 3000 fpm, the confidence of this press technology, called Sunday, can be a new device trend for thermoset web presses. However, with the recognition of gapless technology, it has begun to be widely used among manufacturers. However, this technology trend was completely banned because Heidelberg Web Printing Systems considered this technology as their proprietary technology and filed a lawsuit against its use. Heidelberg claims that it has applied for 100 patents in the development of this Sunday technology. The results of the two lawsuits in March 1998 prohibit other printer manufacturers from using the concept of gapless blankets. However, in addition to the United States, such disputes in other regions have not yet ended. Therefore, MAN Roland continues to use the gapless concept in Europe. The success of Sunday press technology can be illustrated by the two most recently announced presses. Sunday2000 is a 16/24 page (full sheet/larger than full sheet) commercial printer that is intended for commercial printing. Sunday4000 is a 48-page press for short and medium magazines and high-quality commercial printing market. The latest two types of gapless printing presses have a maximum speed of 2500 fpm. The gapless technology is an important development in the thermosetting web printing press market. In fact, there are several other development trends that are also very important. The development in color printing is mainly related to the prepress operation and the printing process through the CTP technology. The control of the color can be achieved by presetting the ink amount on the printing plate through a closed color control loop. For CTP, the reason it caused the reduction of the basic cost is to reduce the prepress time of the printing press. The method of directly outputting the information to the printing plate reduces the problem of image combination and registration, which are always encountered in the traditional production process. As a result, problems with plate exposure and handling are reduced. Therefore, in the end, the printing press gets the desired color effect and the effect of registering is faster. This significantly reduces the prepress time and related issues such as waste of paper. If the amount of ink ink is automatically preset and then added to the printing press, the preparation time and waste will be reduced again. However, there are not many web presses installed with automatic ink presets. This technology has great potential, but it may take some time before it is fully implemented. Closed automatic color control circuits have long appeared on web presses. Closed circuit automatic color control systems are now available from companies such as WPC, QuadTech, and Graphics Micro-systems. About 50 closed loop systems are in operation in the United States. So, for this system, it will be the main standard option for the main press. Every printer manufacturer will assemble the corresponding press according to the customer's needs, but for them, to combine the printer with the color control, it is necessary to jointly develop a connection software with the color supplier. Quad/Graphics has installed seven such systems and has plans for successive installations. The registration system has now become a standard part of every new web press. Therefore, the closed loop automatic color control system will become a standard part. Installing a closed loop automatic color control system for web presses will make the equipment more efficient. Mitsubishi also pays great attention to the improvement of press unit design. Instead of only making it part of an integrated press production system, they develop them into integrated components of key systems. Although the closed automatic color control loop is theoretically very good, not all printers think the price is reasonable. Closed-color loop systems, like computer-to-plate systems, are new technologies that are of great interest, but the application of these technologies will obviously increase the cost of printers. If a printer can maintain a stable color performance, the cost of closing the automatic color loop control system can be compensated by reducing waste in the preparation process. If you want to install a reliable preset system, this compensation is difficult to achieve. Components such as wetting devices can minimize the amount of water during the printing process to minimize emulsification. The ink roller system is now designed so that there is no shortage of ink ink, even at high speeds. Today's printers are better reproduced and more efficient. Even if the staffing is not particularly high quality, the quality can still be kept higher and more stable under high operating speed, and the waste in the work can be reduced to a great extent. Because the press is a complete system, the machine functions better. The current press is not a separate entity; it should be part of a complete integrated system that connects print customers with print buyers. To make the system more efficient, the biggest challenge for printers is to control waste in every part of the production process and perform the required amount of production at the required quality level. To achieve this process, we must carefully plan the continuous process plan to avoid bottlenecks in the work process so that the cost can achieve the most efficient results. At present, the function of the folder has been transformed into a semi-automatic or fully automatic, button-type folding control, which allows very simple operation between two folding products, thus significantly reducing waste. Changing the web width can also be automated. There is a part of the integrated control system that can automatically control the paper input section, cooling section, and upper folding structure. At present, a new generation of combined folding machines can perform on-line crease adjustments to avoid shutdown operations. The folding machine has a higher automation program. Although the folding technology has been significantly improved, experienced operators must also make strict adjustments to the inside of the folding machine, such as folding plates. It is not new, but there are folding machines with very stable improvement measures, which are pinless folding machines. This type of folding machine can save paper as much as possible. Now, hot