Different CTP Plate Features

The mainstream CTP of the lithographic plate in the future is originally started by machinery and equipment in the production system planning. However, the question of indecisiveness is not to select which kind of machine, but what kind of light source should it match? Is it visible light in the end? Near infrared red? Far-infrared ... ... and so on, and then the use of light sources back to the decision to use what plate, what equipment and operations. The current three major categories of CTP plates:

(1) The silver salt photosensitive infection development method is very satisfactory in terms of price, engineering stability, and resolution. The defect is that the silver halide exists in the waste development and cleaning solution, and the end-of-pipe treatment must be done.

(2) High-sensitivity photosensitive resin, operating conditions, and ink receptivity are as normal as the PS version, but whether the resolution and stability are still to be improved?

(3) The thermal CTP plate can operate in bright room with a high resolution of 5μm. If it can be invented in the future, it will be very ideal if it is free of the development plate. However, it still seems to be difficult to use.

This article gives a clearer explanation of the current and future development of the three media.

Silver salt photosensitive development CTP plate

Silver salt sensitized and developed CTP printing plate has a long development time in technology, regardless of material, process, resolving power, printing capacity and UV ink printing, it has a good adaptability, and the light source is not related to argon laser, The dual-frequency YAG neon and helium neon lasers can all be used to meet the market demand. Although the darkroom or on-line equipment must be processed consistently, the cost is also very reasonable, but only at the end of the pipe, waste treatment, silver salt recovery and Neutralization of pH neutrality can avoid sequelae.

Therefore, in the current world CTP plate use field, the silver salt version still occupies the largest proportion, and the future will not disappear, because it is a mature technology, there is often room for existence. Representative manufacturers include DuPont SDB Silver Edition (when the glue is owned by Affa), and Japan's Mitsubishi Paper Board SDP. Because the silver version is quite popular and customary in the small-volume photoreceptor cameras, the silver salt version will continue to be used in the small-size, fast-moving market in paper-based and polyester-based formats.

Photosensitive resin CTP plate

The high-sensitivity photosensitive resin CTP plate is very similar to the current PS plate in terms of chemical composition and plate construction and use. It is particularly excellent in ink repellency, and the imprint resistance and baking operations are completely the same as those of the conventional PS plate. However, such a high-sensitivity resin cannot achieve a high photosensitivity under photoacid and photosensitive resin molecular bond formation. It must be baked at a high temperature of 160-180° C. in order to make the upper layer of the non-imprinted resin lower layer. Full effect, but also because of this to enter the pre-heating operation before development, or photosensitive to rinse time changes, will make these photosensitive bond acidification can not be stable, so that the development of the quality of the instability of trouble, in the front and back and around In addition, the length of the developing machine also lengthens the length of the developing machine because of this preheating process.

The photosensitive resin CTP plate must be used in the working environment, and it must use a nearly dark working environment. If an automatic version and automatic flushing on-line equipment is used, the bright room can be operated unattended. If the manual supply is used, the plate is fully dark. Under long-term operation in the environment, I am afraid that the operator's intention is not high. In addition, the resolving power of the three current CTP plates is also considered to be the worst in this high-sensitivity photosensitive resin plate from 2% to 98% of line 200. Fujifilm, Affa, and other manufacturers have all launched and it is still necessary to strive to become a meter-stream product.

The thermal Th e rm o CTP plate can be operated in the bright room environment, using a single-frequency YAG neon laser, so regardless of the automated on-line production line, or manual upper and lower plate production, photolithography can be made under normal circumstances. The resolving power of the thermal printing plate reaches 1% of the reproducibility of the 600 lines, which is what everyone calls the embarrassment. Because it is necessary to realize the FM frequency modulation network printing, it is very easy to complete the printing plate operation with 3000μp i or more frequency modulation network with 10 μm spot sensitivity.

Currently, in the world, the Creo machine with Kodak thermal printing plate is more popular in the United States. This version can print excellent quality of the imprint, which is what customers like to see, but the thermal tolerance of the printing plate is Extremely narrow, because of the large changes, so it is extremely difficult to work within this narrow tolerance. Many early printing machines that bought this equipment will not be able to sustain and stop production. Some large printing companies in the early days of production continue to use thermal CTP. When printing plates, Kodak's technical staff must also work to adjust and instruct them in the printing factory. It can be seen that there are still many areas for technical improvement. Fuji, A g fa, Konica, P re ss tek and other companies all sell thermal CTP plates.

Another obstacle for the introduction of CTP plates is the high price of the plate. Some people in the industry believe that the CTP plate not only replaces the PS plate, but also replaces the composite function of the film output machine. Therefore, the cost of the two materials is combined. Is it reasonable to calculate the price of a CTP plate for payment?

Source: Print China