The advantage of thermal CTP plate making technology is
which is the better between thermal CTP and visible CTP system? It has been decided eight years ago. The first application of CTP is visible light imaging technology, and due to the launch of Clio platesetter 3244 and other visible light direct imaging equipment, the first round of CTP purchase climax occurred around 1994. However, with the launch of the first thermal imaging system in 1996, the discussion on which is the best imaging technology has obviously been settled
so why is the result thermal rather than visible light? The answer is simple - thermal technology is more suitable for printing plants than visible light. In June, 1995, in Seybold's report on the publishing system, it accurately predicted that "thermal edition technology seems to have a lot of appeal to printing plants... Many experts believe that thermal edition is the direction of the future."
the market has also proved this. Once thermal technology was introduced, almost all printing plants that bought visible light CTP in the early stage upgraded from visible light to thermal. Eight years later, although the publicity of violet laser CTP is very strong, the choice of thermal sensitivity is still the general trend. This is because the fixture that drives the printing factory to invest in CTP has no fixed structure (for example, the metal wire can be clamped by winding or two flat plates. The fundamental reason is not changed, and it is impossible to change.
so what factors urge the printing factory to invest in CTP? First, it is to reduce the production links and save time and money. This is what any CTP can do.
second, it is also more important to eliminate the variable factors in the process of printing plate imaging. These variable factors will directly affect The printing workshop is the Department with the highest cost in the printing factory. Its effects include extended adjustment preparation time, increased material consumption, decreased printing quality caused by inaccurate proofing, inability to ensure accurate addition (am and/or FM), and unstable printing quality. In a word, the great potential of printing plate combined with GMT and lwrt materials, such as the direct consequence of instability, is the increase of cost, the decrease of profit and the decrease of customer satisfaction
thermal CTP is superior to visible light CTP because visible light plates use photosensitive coating, while thermal coating provides binary imaging mode, and it will not be exposed until the critical value
advantages of thermal sensitivity
if the heat energy is insufficient, the printing plate does not image. Once the energy reaches the domain value, it will cause phase transition, and then cause the chemical decomposition reaction of the coating. This means that there is little possibility of underexposure or overexposure. In the past 100 years, binary imaging has been the goal of most prepress R & D departments, and the high energy of thermal imaging makes this goal a reality. Therefore, the imaging of thermal CTP system is more stable and consistent, which is the ultimate goal of prepress and printing
on the contrary, the visible light plate should be very sensitive because it can image with very low energy exposure (it is measured in milliwatts, while the thermal laser is measured in watts). The weak exposure energy can only make subtle changes to the photosensitive emulsion, and this subtle change will be infinitely amplified during the printing process. As long as the plate is slightly overexposed or underexposed in the process of manufacturing, storage, temperature, humidity or development, or some changes will have a serious impact on the imaging area, making the imaging either large or small. The sensitivity of the visible CTP system makes its imaging stability not much improved, or even worse, compared with the phototypesetting system
the thermal plate coating will not react to light energy, so there is no need for darkroom operation. Frankly speaking, are we going to return to the darkroom in 2005? Does plate making in red or yellow light really represent scientific and technological progress
thermal desmocomp is currently used in the manufacturing of components of light commercial vehicles. CTP has other powerful functions in addition to its dualization. First of all, it is the only technology that can image on three main printing methods, namely offset printing, flexo printing and gravure printing. Secondly, thermal imaging technology is also applied to most digital offset printing machines, including Heidelberg, Komori, Manroland and gaobao. In addition, thermal imaging technology can be used not only to expose plates, but also to expose proofing media. More importantly, it can also be used to expose non rinse printing plates - the next major development direction of prepress technology. Visible CTP plates need chemicals to be developed, which is a major variable factor affecting the imaging process mentioned above. The application of thermal laser direct imaging without relying on chemical washing reduces the influence of variable factors and ensures the stability, image integrity and repeatability of plate making
finally, the cost of developing agent storage and waste liquid treatment is also a major problem. The output energy of purple laser diode is only 5 MW (about the same as the laser indicator energy used in our demonstration, which is lower than the scanner used in most supermarket cash registers), which is extremely weak according to the standard of thermal sensitivity. The output energy of violet laser can only be imaged on the most sensitive coating (high-speed silver salt plate). Silver salt version has been available for many years, and there are not many new changes
in the latest "2004" technical report "released by vantage strategic marketing, it is believed that the sales of thermal plate making machines developed rapidly last year, reaching 64% of the total global sales, making the installation of thermal machines reach 56%, and thermal plates account for 68% of the consumption of CTP plates. Unfortunately, most of the people who buy violet laser CTP are small printing houses. They don't have much resources to compare various technologies, and they are more used to adapting to the shortage of equipment. For printing enterprises, it is actually risky to adopt a system that looks "similar" to thermal sensitivity in this highly competitive printing market
on the contrary, the widely used thermal technology has brought real benefits to small printing plants, such as lower prices of plates and equipment, manufacturers' investment in research and development, and a prosperous secondary market. In addition to the low price of the machine, the operating cost of the thermal system is also very low
of course, the new violet laser products have been improved. It is mainly that the current purple laser uses solid-state devices (diode laser heads), rather than the gaseous laser used in the past two decades. This improvement is very important. Why? Compared with the gas laser head in the past, the price of diode laser is relatively cheaper, about several thousand dollars. But when the market hype subsides, you will eventually find that although purple laser is the ideal wavelength for visible light imaging in the future, compared with thermal sensitivity, it does not represent the progress of the printing industry and does not bring real benefits to printers. In short, the imaging and processing problems brought by violet laser imaging are actually the reason why the printing industry shifted from visible light to thermal sensitivity eight years ago
Copyright © 2011 JIN SHI