Method for manufacturing lithographic printing plate base

Abstract

The invention discloses a method for preparing an offset press printing plate base, which comprises following steps: coating substrate dispersion liquid on at least a lateral surface of the selected substrate; curing the substrate dispersion liquid at a temperature of 100 to 350 DEG C to form a substrate layer; coating hydrophilic dispersion liquid on the lateral surface of the substrate layer which is far way from the substrate; curing the hydrophilic dispersion liquid at a temperature of 100 to 350 DEG C to form a hydrophilic layer. In the preparation process of the offset press printing plate base, the method ensures that the substrate layer and the hydrophilic layer can be rapidly cured at high temperature and ensures that the substrate, the substrate layer and the hydrophilic layer donot deform and / or denaturize. Therefore, the method can greatly improve the production efficiency under the condition of ensuring the quality of the printing plate base.

Description

technical field [0001] The invention relates to a method for preparing a printing plate base, more specifically, the present invention relates to a method for rapidly preparing a lithographic printing plate base. Background technique [0002] Lithographic printing technology is the main printing technology commonly used in the printing industry at present, and the most commonly used ones are PS technology and CTP technology. [0003] Both PS technology and CTP technology use the principle of oil-water separation for printing. That is, during the printing process, all the non-graphic parts of the surface of the printing plate base are evenly covered with water. When the printing ink is supplied to the surface of the printing plate base, the non-graphic parts covered by water cannot be stained with printing ink, so the printing ink It can only be spread on the graphic part, so that the graphic part covered with ink and the non-graphic part covered with water are clearly separ...

AI Technical Summary

Problems solved by technology

[0005] Therefore, the existing PS printing technology has many disadvantages as follows: 1. It is necessary to carry out acid treatment and electrolytic anodizing treatment on the substrate, and the production process has high power consumption, high water consumption, low vehicle speed and low efficiency, which not only increases the manufacturing cost , and will cause serious pollution to the environment; 2. After many times of printing, the traditional PS printing plate base often appears dirty on the non-graphic parts, so the current general PS printing plate base has a short service life. In the production process of the traditional PS printing plate base, it is generally made hydrophilic by corroding and anodizing the base. The main component of the hydrophilic layer formed by this corrosion is Al, which itself is not excellent in hydrophilicity. 2 o 3 , Wear and tear will occur after repeated use, which will reduce the hydrophilicity, and the hydrophilic surface of the printing plate base will easily lose its hydrophilicity during use. In addition, the photosensitive layer will be developed after exposure to remove the unexposed photosensitive layer. 3. Because the traditional PS plate has high requirements on the corrosion resistance of the substrate, and the hydrophilic layer must be formed through the anodic oxidation step , so the substrate is strictly required, it must be aluminum with high purity

However, this patent application has the following disadvantages: First, due to the properties of the hydrophilic lithographic coating it uses, it is necessary to heat the substrate in the temperature range of 140°C to 180°C for 8 to 12 hours before coating. Minutes to shrink the substrate so that it has a shrinkage rate of 0.2% to 2.0%, which increases its process complexity; secondly, the performance of the hydrophilic lithographic coating it uses depends largely on the amount of silica Even particle size, which therefore limits the ratio between catalyst to accelerator to crosslinker to binder to pigment to anionic surfactant to silica microparticles to 1:2 to 1:2 to 2:1 to 20 :25 to 60:80, which basically excludes the possibility of using other oxides, but in fact other oxides can also be used to prepare hydrophilic lithographic coatings; moreover, it limits the base material of the printing plate to the polymer sheet material, which basically excludes the possibility of using other materials, but in fact other materials can also be used as the substrate of the printing plate; finally, the means of modifying the substrate include etching, acid treatment, etc., which will pollute the environment and damage the base

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