Application of the hottest thermal CTP in newspape

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The application of thermal CTP in newspaper printing

computer direct plate making technology (CTP) has gone through more than 10 years. So far, the choice of the market clearly conveys such a message: thermal imaging technology is the choice of Commerce, packaging and direct printing; In the newspaper industry, photosensitivity and thermosensitivity are at odds with each other. From the perspective of the gradually rising installed capacity in the world, the growth rate of thermosensitivity is significantly higher than that of photosensitivity; Of course, photosensitivity still accounts for a considerable market share (mainly in Europe) due to long-term accumulation and early installation. The country with the most thermal applications is Japan's newspaper industry, which accounts for 85% of the share. It is also the country with the most popular application of FM printing in the newspaper industry at present; Aluminum, a hot automotive material in North America, sprouted. Sensitivity reached 53% in 2007, and the increment of Asia Pacific newspaper industry is also dominated by thermal sensitivity

by the end of 2007, the total installed capacity of CTP in the world was about 41000, and the total consumption of plates was 330million square meters, of which 95 million square meters were photosensitive and 230 million square meters were thermal, accounting for 70% of the market share; The total installed capacity of CTP in the global newspaper industry is about 4400, and that of Kodak newspaper industry is more than 1200; There are more than 1600 thermal sensors in total, accounting for 37% of the market share

1. Which technology of thermal sensitivity and photosensitivity represents the development direction of the newspaper industry

which technology represents the development direction of the newspaper industry, which is also the most controversial issue when the newspaper industry invests in CTP; Speaking of this problem, it's better to look at the development direction of newspaper printing first. Large scale, large printing volume, speed first and printing quality second have always been the true portrayal of newspaper printing. Therefore, photosensitive has always believed that it is the most suitable technology for the newspaper industry, because the plate making speed once dominated. However, the unique application of thermal technology in the development of CTP in the newspaper industry provides some references for current customer investment. Is the printing quality really so unimportant? If customers can not only enjoy the speed, but also provide high-quality printed matter, but also experience the many conveniences brought by technological progress, why should they stay on their toes? Let's review the development history of the two technologies. You should be able to make your own judgment:

photosensitive camp:

in 1997, Agfa launched the first 532 nm green laser silver salt CTP (using the green laser silver salt version, and the earlier is the 488 nm green laser); In 2001/2, the violet laser CTP with a laser wavelength of 405 nm was introduced. At that time, the laser energy was 5 MW, which was suitable for the violet laser silver salt version; In 2004/5, the purple laser CTP with a laser wavelength of 405 nm (30 MW of laser energy) was launched. The applicable plate is purple laser polymer. Now the laser energy has been increased to milliwatts. Why should the laser energy be increased? In addition to emphasizing the increase speed, the suppliers of photosensitive equipment are mostly vague about the development considerations behind it, which will be discussed later; Photosensitive laser wavelength has changed several times in the past 10 years. The important thing is that the plates applicable to customers are not universal for each change, and silver salt has become an obsolete technology. Therefore, the customer said that CTP technology changes too fast and the technical compatibility is poor, which precisely refers to the changes in photosensitivity. So far, the installed capacity of domestic newspaper industry is about 124. Among them, there are 46 purple laser polymers, 38 thermal sensors and 40 silver salts mentioned above. Of course, if the upgrade cost of the machine is almost the same as that of the new equipment, the upgrade is of little significance

thermal camp:

in 2000, when the development of commercial thermal CTP was very good, Kodak launched a newspaper CTP with a laser wavelength of 830 nm, which was applicable to all thermal plates, but the speed was still slow at that time, only 40 folios/hour. In May 2004, it launched a high-capacity CTP with the same laser wavelength, with a maximum speed of 100 folios. In June 2008, it launched the thermal CTP with the largest publishing capacity in the whole newspaper industry, with a speed of folios/hour, In the whole 8-year development process, in addition to the speed increase, the laser wavelength remains unchanged, and the applicability of the plate remains unchanged; In particular, it is worth mentioning that the CTP installed by China Youth Daily at the end of 2002 is still in use as the main force. This model can upgrade the on-site speed, commercial accuracy and plate size according to the current needs of users, which can be said to have a high degree of effective use of investment; Most of the silver salt CTPs purchased in the same period have been idle, and the non environmental protection and high price of plates are the hidden dangers of continued use. Therefore, every progress of the thermosensitive camp has its technical consistency and stability, and it cherishes the investment of customers. At this point, it is necessary to mention the laser energy mentioned above, because the development of plate technology is faster than CTP equipment. Now the mainstream plate technology is already free of processing plates. In short, it saves the follow-up printing process while keeping the CTP equipment unchanged. This is of course a great contribution to the timeliness of CTP technology. For the photosensitive equipment that has always claimed its first speed, Such efficiency improvement may not be achieved by relying solely on the progress of CTP equipment technology. Therefore, the development of purple laser processing free version has become a top priority. However, as we all know, the washing of plates is to achieve the function of developing and fixing, and the washing steps are omitted. Therefore, this problem needs to be solved in the process of plate making and exposure. Therefore, the laser energy required for the treatment free plate is much higher than that of the ordinary CTP plate. For the thermal laser head with high energy, it is natural to treat the treatment free plate. Customers do not need to replace the CTP equipment, and just use it directly, For purple laser equipment, it is urgent to improve the energy of their laser head as soon as possible to catch up with the trend of technological progress. Therefore, there is a move to increase the energy of purple laser equipment from 5 MW to 100 MW. You know, purple laser equipment suppliers once complained about the energy of laser head. Even so, it is impossible to complete the point fixing on the plate only by relying on 100 MW of energy. Therefore, they still need to complete the final point fixing with the help of the process of printing, but this time they avoid the process of developing with chemical solvents and use water mixed with special solvents to fix instead. Strictly speaking, the processing free plate of violet laser can only be called the chemical washing free plate. For users, it still can't save the washing time, washing equipment and washing process

thermal technology has been greatly limited in the initial process of newspaper CTP development due to its relatively late involvement in the newspaper market and its relatively slow speed in the early stage. Now Kodak thermal has made a new breakthrough in speed. The fastest publishing speed is more than 140 folio editions, and it has a comprehensive product series, which will inevitably have an impact on the development of the newspaper market

2. Outstanding features of Kodak thermal CTP

1) the thermal imaging technology is stable and reliable

Kodak's unique squarespottm square light spot thermal imaging technology has won the GATF Award for five times since its launch, and ranks first in the field of CTP. 12000 sets have been successfully installed worldwide, more than 400 sets have been installed domestically, ranking first in the market for six consecutive years, and is recognized as the best thermal imaging technology

the exposure principle of squarespot TM square light spot thermal imaging technology is as follows: a total of 20 infrared laser diodes are installed on the laser strip, and the light emitted by each laser diode is focused on the whole light valve through the prism to make the energy distribution more uniform. The light passes through 240 square windows opened on the light valve, which are value= "10.6" unitname= "m">10.6mm x value= "2.5" unitname= "m">2.5mm, and then focuses on the printing plate through the prism, Therefore, even if several laser diodes are aging gradually, normal exposure can still be achieved by properly adjusting the laser energy. In addition, the current value of the laser diode can be checked through the remote diagnosis system to accurately predict the life of the laser head

since Kodak launched the first generation of thermal CTP in 1996, the laser head has been upgraded five times in the past 10 years, and it is more and more stable and reliable while keeping the laser wavelength unchanged. Kodak CTP uses a diode laser, which is lit only when exposed. According to the survey of Kodak's huge installation volume all over the world, the average effective exposure time is 5500 hours, that is, the average service life has reached 4-5 years. In addition, customers can skillfully take advantage of the convenience in Kodak's service terms, even if the cost of replacing a laser is very low

generate accurate points and shorten the printing preparation time

usually, a printing point is composed of multiple laser points, which are divided into many light grids during raster image processing. Most other manufacturers fill this point with circular laser points, which are larger than the light grid, so the point size is inaccurate. Moreover, because the Gaussian circular laser point energy gradually decreases from the center to the edge, the formed point edge is not sharp and steep, the ink is easy to emulsify during printing, and the adjustment of ink balance takes more time

Kodak adopts square laser dots, which are completely matched with the grating lattice, and the energy distribution is uniform. Therefore, the edge of the dots is sharp and clear, which can be accurate to 1% to 99% of the dots. Therefore, when printing, the inking is fast, the ink is easier to achieve stability, and the preparation time can be greatly shortened. Moreover, the expansion rate of the dots formed by the square light dots in the printing process can be effectively controlled, which can fully improve the printing quality and production efficiency of the existing printing machines

2) the printing process is simple and easy to realize FM printing.

FM plus technology has been introduced for nearly ten years, but it is rarely applied to large-scale production, because they all use Gaussian circular laser points, whose energy distribution gradually decreases from the center to the circumference, and the exposure boundary is not clear. With the change of laser energy, emulsion thickness and development conditions, the point size and edge are more likely to change. Moreover, the diameter of circular laser points is mostly more than 15 microns, which is larger than the optical grid. When the points are randomly distributed, they cannot accurately represent a certain value, and there are always some unpredictable changes. Therefore, it is necessary to constantly adjust the printing conditions, it is difficult to establish stable process parameters, it is time-consuming and laborious, and it is difficult to put into mass production

Kodak uses square laser points with a minimum side length of 10 microns, which is accurately matched with the light grid, the energy distribution is uniform, and the exposure boundary is very clear. The changes of laser energy, emulsion thickness and development conditions have little impact on the points. The edge of the points is sharp and stable, and the fluctuation is less than 2%. It can be accurately predicted. The adjustment of printing is relatively simple, and it is easy to establish stable process conditions, so it can be widely used in the actual production environment. Kodak is currently the only manufacturer in the world that can provide 10 micron FM plus technology, and a large number of customers have been put into production and application. Through frequency modulation, printing ink can be saved by% and can be printed on paper with value= "40" unitname= "g">40 g without ink penetration

due to Kodak's unique laser head exposure technology, Kodak CTP can make 175 lines of plate at 1200dpi for semi commercial printing on light coated paper, or Kodak's shifangjia FM plus technology can be used to achieve the quality of commercial printed matter of newspaper printing

3) dynamic focusing and temperature compensation to ensure accurate registration

Kodak CTP adopts external drum thermal imaging technology. The printing plate is clamped on the drum with a strong version on one side and fixed on the drum with a strong magnet on the other side. The upper and lower versions are smooth. The physical characteristics of exposure are similar to those of loading to the printing drum. When outputting high-line or frequency modulation, fine points do not deform. When imaging, the drum only has 200 rpm, and the operation is very stable

Kodak's unique dynamic focusing and temperature compensation system has been used in imaging

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