Poor people's CTP computer direct plate making method
CTP computer direct plate making not only saves the negative output engineering, but also reduces the trouble of negative material and its development and fixing solution recycling. On the other hand, the equipment price of CTP's printing plate output machine is very high, ranging from 70 million to more than 10 million yuan. Not all output centers and printing plants can be exempted from the burden. Moreover, the CTP printing plate price is often twice or more than that of the traditional PS version, such as stretching, stripping, etc., which is higher than the sum of the two materials of negatives and PS version. This burden is in some efficient newspapers or printing industries with high profits, Maybe they don't care, but in some printing industries with low profits, they are very hopeful that the traditional PS version, CTP, which uses ultraviolet and particle convex mirror to focus, can make a way for the future
the simplest CTP is to use the traditional PS version and the platform inkjet printer. The method is to put the unexposed positive PS version on the printer table, and then spray the page file on the PS version with the inkjet printer (the oily ink is easy to adhere, and the water-based ink is easy to wash away). After drying, put it under ultraviolet light for moderate exposure, because the image inkjet is directly attached to the surface of the printing plate, and there is no need for negative and PS version vacuum procedures, There will be no poor sealing, and then the printing will be completed. This kind of equipment is not expensive, and the consumables are exactly the same as the CTP plate making at present. The only thing that cannot be compared with the advanced CTP is estimated that in 2011 (2) 030, the inkjet Lister has only about 600dpi analytical power, which is only suitable for text, lines and 80 line prints. The finer text and dots need to be developed in the future
CTP of large rubber plate uses the original CTF image output machine and changes the negative to CTP sensor of polyester substrate. According to the data error of the pressure testing machine, the plate used for printing plate is thicker than CTP negative, so the laser focus must also be changed. However, the most important thing is the difference in the development method. Originally, CTF is the traditional development of oxidation method, but the silver salt development of CTP is infectious development, that is, two-stage development. The photosensitive part first develops into a black water absorbing non image part, and then the non photosensitive silver salt infects the emerging plate to become an image twice. In this way, the equipment can be used both for negatives and printing plates, and the plate price is low, but the printing plate is pressed down and rolled and stretched due to a long time to check whether the emergency switch is pressed, There will be difficulties in overprinting, and the printing quality is slightly inferior
small size non aluminum CTP printing plates, including the above polyester silver plate or paper-based plate, some only need to be made by laser Lister with resin toner imaging baking, and some also use charged plate imaging to obtain printing plates. One of the features of small-size CTP is to provide plates automatically for a long time with coiled plates, which can greatly reduce the production cost
like Riso rapid printing machine, it uses wax paper perforation technology to achieve digital control imaging. Naturally, it is also a CTP with extremely low cost and fast work, but in the fields of small size, chromatic and black-and-white work
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