Inkjet Computer Direct Plate Making

In recent years, there has been an upsurge in the use of direct plate printing (CTP) in the printing industry. This is another printing revolution since the printing technology revolution triggered by laser illumination. Now, CTP technology has been recognized by the international printing industry as the development trend of the printing platemaking process, and has been listed by the Economic and Trade Commission of China as the content of the eight new technology projects that need to be introduced urgently. First, the situation of the direct plate making (CTP) According to the survey of American printing technology authority GATF, 55% of the 100 large printing companies in the United States have adopted the CTP system, and the installed and used CTP system in the world has reached 6,200 sets. It is expected to reach 12,150 in 2000. The fastest newspaper industry in China accepts new technology. By the end of 2000, China’s newspaper industry system had only 10 imports (including those that had not yet been ordered). The main reason for the slow introduction is that the direct plate making system is expensive, and non-general printing companies can afford it. Mitchell Limburg in Germany said in his book "Computer-to-plate Technology" that "CTP's initial investment is between 200,000 and 700,000 U.S. dollars. This is a considerable figure for any platemaking institution." Specific to our country's actual situation, the introduction of equipment tariffs, VAT, generally increase the investment by more than 40%. Therefore, the introduction of a direct plate-making system requires 280,000 to 980,000 U.S. dollars, or approximately 2.316 million to 8.015 million U.S. dollars. For most printing companies in China, this is very difficult. This is a huge obstacle to the promotion of direct plate making technology in China. At the same time, the currently imported plate-making materials are too expensive. Each template needs 80-100 RMB, which is 3 to 4 times the price of the domestic ordinary PS plate. This is more difficult for the general printing factory to accept. Of course, with the development of equipment and materials, prices will surely decrease gradually, but this will take time. The mainstream of foreign computer-to-plate systems is the silver salt system and the thermal system. The advantages, disadvantages, and scope of application of these two systems have been familiar to the printing industry, and I will not go into details here. This article will briefly introduce a computer-to-plate system using inkjet printing equipment. Second, the development of foreign inkjet direct plate making At the Drupa 95 exhibition, two companies developed products using inkjet technology, namely the products developed by Italy's Lastra with a resolution of 800dpi, and produced by Polychrome, with a resolution of The 600dpi LJP-1000 equipment can be upgraded to 900dpi and 1200dpi resolution products using a dedicated hot melt ink. In November 1997, Lastra launched the inkjet direct-impression (CTP) device that uses Extrema graphic inkjet imaging and direct-on-machine printing after photocuring. According to another report, Polychrome's hot melt inkjet CTP plate has a printing resistance rate of 150,000 impressions, and can be over 1 million impressions after baking. At Drupa 2000, IrisGraphies and HitachiKoki also launched the inkjet technology CTP system. As a platemaking process, inkjet CTP systems appeared as early as the 1970s. In 1978, HOECHST applied for a patent for the ink jet platemaking technology developed by the company (Patent No. German Patent No. 2806802). This patent uses a surface-roughened and anodized aluminum substrate, ink-jet printing on an ink-jet printing machine using water-based or oil-based inks, heat treatment at 120°C, and hydrophilicization of blanks. Processing, then you can print on the machine. Early development of such products included Tokyo Chemical Corporation and Canon Corporation. Tokyo Chemical's products are similar to those used by HOECHST, and Canon’s published patents use inks dispersed in water to be printed on an ordinary PS plate by ink jet, imaged on a photosensitive coating, printed, and developed. Can be printed on the machine. The image resolution of the inkjet printing equipment introduced earlier was relatively low, it was difficult to form a plate with a higher image quality, and industrial products could not be formed. In the mid-1980s, large-format inkjet printing equipment with higher printing precision appeared, and the quality of image printing improved. Last year, Epson introduced the Epson Stylus Pro9000 and Pro9500 with a resolution of 1440×720 dpi, and HP’s HP Design Jet800PS inkjet printer with a resolution of 2400×1200 dpi. Due to the advancement of printing technology, the second wave of research and development of inkjet type direct printing plates has been triggered in recent years. Many companies, such as Polychrome, Fuji, Canon, Konica, Kodak, Toray, Toyobo, Epson, Japan Paint and Japan's Mitsubishi Chemical have issued patents. Inkjet printing CTP technology can be used with the ordinary PS version of the base, photosensitive coating can be photolytic or photopolymeric. It is also possible to print images directly on a roughened, anodized, porous aluminum plate. The ink used may be a water-soluble ink solution, a thermosetting ink, an ultraviolet (UV) curable ink, or the like. Printed on an ordinary PS plate, printed, printed, and printed on the machine. After bare printing (that is, only roughening and oxidizing treatment, but not coated with sensitized coating for printing plate), it can be directly printed on the machine after printing. This is a non-wet processing type printing plate. No pollution to the environment, known as green products. As Bob Solar's chief executive Bob looks to the future, he said: "From a long-term perspective, ink-jet printing plates have great potential for development because it is a truly green environmental protection material. From the above, the plate used in the inkjet CTP system is a blank plate with an ordinary PS plate or a non-photosensitive layer, so its cost must be low. It should be comparable to or cheaper than the PS plate. The advantage of CTP is that it saves film, saves money, and reduces pollution to the environment. Inkjet computer-to-plate systems are based on the original CTP technology. However, as an inkjet type plate making and printing apparatus, the price of a platform printer manufactured abroad is still relatively expensive, and it is estimated that the price of each unit is also more than 200 to 3 million RMB. It is also more difficult to promote. So far, foreign ink-jet direct plate-making systems and plates have not yet entered the Chinese market. Third, the development of China's ink jet direct plate-making system and media due to the introduction of large-format computer inkjet equipment, especially the Epson StylusPro9000 large-format color inkjet printer into the Chinese market, its performance and price is very noticeable. Its print format width is 1118mm, resolution is 1440×720dpi, price is 80,000～90,000 yuan, and dye ink solution is used for printing ink. Can it replace the official plate-making equipment for plate-making? If it can replace, it can also use the cheap ordinary PS version, put them together to form the cheapest direct plate-making system. Although it can not compare with the image quality of foreign silver salt and thermal plate system, it is not inferior to them in the market positioning and level, which is determined by its own advantages. In its market positioning, it aimed at book printing and color newspaper printing. These two markets require a resolution of less than 133 lpi and a repeatability of less than 25 microns. After research, it proves that this market position is correct. The printing plate produced by using inkjet CTP technology is printed on the machine, the text is clear and sharp, and the color of the picture is vivid, which surpasses the printing effect of the general laser printer. The low price of the ink jet direct plate making system and the cheap plate material price are not matched by the silver salt system and the thermal system. Because of this, it is very suitable for our country's economic situation is not yet developed, can make China's general printing companies can quickly establish a CTP system. In 1999, the author completed the research work on domestic inkjet CTP plates and filed national invention patents in the same year. Now this result has been put into mass production by Beijing Prime Electronics Co., Ltd. and domestic ink-jet CTP plates have been put into the market soon. At the same time, Beijing Stone Investment Co., Ltd., Beijing Tongruida Co., Ltd., and Beijing Sinhongde Co., Ltd., respectively, have introduced inkjet-type direct plate-making systems that combine computer and printing software with Epsonstylus Pro9000 inkjet printers. In the inkjet direct platemaking system introduced by these three companies, Beijing Tongruida’s outlets are well controlled and can fully meet the requirements for plate-making and timeliness of newspapers and periodicals. Beijing Pritech Electronics Co., Ltd. introduced a generation of products based on the ordinary positive-picture PS version of inkjet printing products, the company also plans to introduce a second-generation products without wet operation. In addition to the advantages of the ink jet direct platemaking system referred to in the foregoing, it also has the following advantages: The silver salt or the heat sensitive system cannot be separated from the high power output laser or the complicated optical system, and its own price and maintenance cost are also expensive. The ink-jet direct plate-making system is much simpler and cheaper to repair. IV. Prospects In recent years, the hardware and software of inkjet printing equipment have developed rapidly. Following the release of Lexmark 752, the first 2400dpi color inkjet printer by Lexmark International Ltd., HP also introduced the HP designjet 800 and 800PS inkjet printers with a print accuracy of 2400×1200 dpi and faster printing speeds. A1 format line graphics only takes 60 seconds. This undoubtedly laid a solid foundation for the further development of the inkjet platemaking system. It can be imagined that on the basis of the improvement of equipment performance, this cheap, pollution-free green CTP system will be widely recognized by many printing industry peers.