Thermal ablation board is generally coated with two layers, the bottom layer is an ink-loving layer and the upper layer is a hydrophilic layer. During exposure, laser energy ablates the hydrophilic layer, exposing the ink-hydrophilic layer to form pictures and texts. The unexposed part remains hydrophilic and the layout is blank. Thermal ablation technology is not smooth in practical application, mainly because the dust and debris produced after ablation will affect the accuracy of optical components of plate making machine, which is not good for health and environment. Moreover, the blank part of thermal ablation plate is hydrophilic coating, and the ink balance control ability and printing resistance are not as good as those of traditional PS plate and CTP plate.
The non-treated plate with polarity conversion technology is coated with a single layer, and the drug film is hydrophilic (or lipophilic). After exposure, the polarity of the drug film layer becomes lipophilic (or hydrophilic), and the exposed part is the graphic (or blank) part of the printing plate. This printing plate can be directly printed on the machine without any treatment after exposure. However, due to their unsatisfactory printing control and printing resistance, there is still a long way to go before large-scale commercial application. Untreated CTP plate has many advantages. After inspection exemption, the production efficiency is improved, chemical development is not needed, the energy consumption during exposure is reduced, the overall plate-making cost is reduced, and the plate-making process cycle is shortened. With the increasing emphasis on environmental protection today, its advantages-no pollution to the environment, are more obvious. Although the price of CTP plate without treatment is higher than that of conventional CTP plate, the former can save 35% of the total cost in terms of overall plate making cost, so the high price of each disposable plate is understandable. Kodak CTP Kodak Capricorn GT Thermal Plate Kodak GT Plate is the largest Kodak CTP plate in the domestic market at present.