IV. Computer-to-plate (CTcP) and Features of Traditional PS Plates
CTcP technology is the English abbreviation of Computer to Conventional Plate. Its meaning refers to direct computer plate making on the traditional PS plate material. It uses a UV light source with a laser wavelength range of 360 nm to 450 nm to expose the traditional PS plate to make a printing plate. As early as Drupa's 2000 International Printing Exposition, the German basysPrint company first introduced a UV-Setter platemaking machine that uses traditional PS plates for direct plate making. Since then, as a epoch-making direct-to-platemaking technology, CTcP technology has entered the big stage of printing history. In order to directly use the data for exposure, basysPrint Germany has developed digital screening imaging technology (DSI). With a digital micro-mirror device, there are approximately 1.3 million independently controllable micro-mirrors on a 2 cm square surface. In the imaging process, the light irradiated on the micromirror is projected onto the plate material through the lens, and finally an image consisting of halftone dots is generated on the plate. Due to the unique DSI-specific technology and special optics used by the basysPrint company's CTcP system, the edge of the generated network is sharp and sharp. It uses square dot imaging for precise, seamless connectivity without the need for edge overlap.
The main features of this CTcP system are high quality, high efficiency and significant economics:
The first is to reduce the process of film and printing in the traditional process, saving consumables and related expenses.
The second is that compared with other CTP technologies, the CTcP system has a large price advantage due to the use of traditional PS plates, developing machines, and potions, enabling low-cost operation of production. The third is that the CTcP system uses UV photosensitive media, which can be easily operated under bright room conditions, and companies can introduce the system without changing the other operating environments before printing. Its light source uses UV lamps, its lifetime has been increased to 2,500 hours, and its price is less than one-tenth of the laser light source, so the cost of operation and maintenance of the equipment is very low. The fourth reason is that since the CTcP system can use ordinary PS plates, developing and developing machines and chemical liquids, customers only need to install a UV-Setter platemaking machine, and they can perform better and faster in the original enterprise. In addition, because the CTcP system is the same as the printing process using the traditional PS version, it has great advantages in process technology management and the replaceability of CTcP and traditional process printing. Although the CTcP system entered the market later, the improvement in light source life and exposure speed reflected the rapid development momentum. In the past year or two, it has been developed at an extraordinary rate. At present, nearly 500 CTcP platesetters have been installed and used in the world. Among them, BasysPrint UV-Setter series CTcP systems have sold more than 400 units.
V. Future Development Trends
At present, CTP technology is relatively mature, and its market has a relatively complete distinction, such as: newspaper market, commercial printing market, and quick printing market. In addition, the matching of CTP equipment with the printing press format has also been increasingly perfected. Many manufacturers have launched CTPs from four-on-one, half-on, full-sheet, and double-sheets to CTPs and super-duplex sheets. The categories are very complete. Commercial CTPs mainly pursue large format, high quality, and high production efficiency. In response to this requirement, manufacturers have mostly introduced inner drum and outer drum CTP equipment. In terms of accuracy and stability, the inner drum type is slightly better, and most high-end photo-composing machines currently use inner drum technology. However, in the early days of thermal printing, the outer drum type had unique advantages because it allowed the laser spot to stay longer on the plate and increase the speed by increasing the number of beams. As the sensitivity of the thermal CTP plate continues to increase, this advantage of the outer drum type has gradually lost. However, for different plate sizes, the inner drum type and the outer drum type each have their own advantages. Generally, the full width sheet below is suitable for the inner drum type technology, and the larger sheet type is more suitable for the outer drum type technology. From the 2004 International Printing Expo, we have seen that the two countries have each occupied half of the country.
The CTP used in the newspaper industry is mainly pursuing high production efficiency and high stability. For this reason, various manufacturers have introduced platform-based CTP equipment. For example: Agfa's Polaris Polaris series, Model 200 output speeds up to 235 plates per hour (57mmX36cm, 1016dpi), much higher than any commercial CTP device. This platform-type CTP has a resolution of 800 to 2540 dpi and can be adjusted in multiple stages. It is sufficient for newspapers to meet the quality requirements. The platform-type mechanical structure is very simple, so the stability is extremely high and maintenance is also very convenient.
In short, based on the above analysis, we can make such judgment: No CTP technology has yet become an absolute advantage, and no imaging technology can prove to be the leader of the entire market, even in the foreseeable future. might have. At present, the CTP market is dominated by the thermal technology, but this technology is encountering the strong impact of the new violet laser CTP technology and the traditional PS plate material CTcP technology. In the next few years, besides silver salt technology, there will be coexistence of various CTP technologies and there will be no qualitative changes. The overall development trend of the market structure should be more balanced and it is very difficult to happen.
Author : Liu Fei Liu Shiliang Foshan Shunde Feiyou Automation Technology Co., Ltd.