Common types of base paper used for corrugated cardboard box paper are: box board paper, liner paper, kraft cardboard, tea board paper, whiteboard paper and single-sided coated whiteboard paper. Due to the differences in the papermaking materials and the papermaking process of each base paper, there are large differences in the physical and chemical indicators, surface properties and printing suitability of the above base papers. The following will discuss the problems caused by the above paper products to the process of starting the corrugated cardboard ink printing. 1. Problems caused by low-grit base paper When using low-grit base paper as corrugated cardboard surface paper, the corrugated cardboard surface will show signs of corrugation. It is easy to cause the obvious flute and the required graphic content cannot be printed in the low concave of the flute. For the uneven surface of the corrugated cardboard caused by the flute, a flexible resin plate with better resilience should be used as the printing plate to overcome the printing failure. Clear and uncovered defects. Especially for A-type corrugated board produced from low-granularity paper, printing by a printing machine will cause great damage to the flat compressive strength of the corrugated board. In addition, after the corrugated board passes through the printing roller and the embossing roller, its edge pressure strength will also be There is greater damage. If the surface rick degrees of the corrugated cardboard are too different, it is easy to cause the corrugated cardboard produced by the corrugated cardboard line to warp. The warped cardboard will cause overprinting and printing slotting irregularities to the printing, so the warped cardboard should be flattened before printing. If the corrugated cardboard is forced to be printed unevenly, it is easy to cause the rule. It will also cause the thickness of corrugated cardboard to decrease. 2. Problems caused by different surface roughness of the base paper When printing on raw paper with rough surface and loose structure, the ink permeability is large, and the printing ink dries quickly, while printing on paper with high surface smoothness and dense fiber toughness, the drying speed of the ink is slow. Therefore, the amount of ink application should be increased on rougher paper, and the amount of ink application should be reduced on paper with a smooth surface. Printing ink on paper without sizing dries quickly, and printing ink on paper with sizing dries slowly, but the reproducibility of the printed pattern is good. For example, the coated whiteboard paper has lower ink absorption than boxboard paper and teaboard paper, and the ink drying is slower, and the smoothness is higher than that of boxboard paper, liner paper, and teaboard paper. The rate is also high, and the reproducibility of its patterns is better than that of lined paper, cardboard paper, and tea board paper. 3. Problems caused by differences in the absorption of the original paper Due to differences in papermaking raw materials and differences in base paper sizing, calendering, and coating, the energy absorption is different. For example, when overprinting on single-sided coated whiteboard paper and kraft paper, the drying speed of the ink is low due to the low absorption performance. Slower, so you should reduce the concentration of the previous ink and increase the viscosity of the overprinted ink. Put the lines, text, and small patterns in the first color printing, put the full version on the ground in the last color printing, which can improve the effect of overprinting. In addition, the dark color is printed on the front, and the light color is printed on the back. It can cover the overprint error, because the strong coverage of the dark color is conducive to the overprint standard, and the light color coverage is weak, and it is not easy to observe even if there is a running rule in the post-print. Different sizing conditions on the surface of the base paper will also affect the amount of ink absorption. Paper with a small sizing amount absorbs more ink, and paper with a large sizing amount absorbs less ink, so the gap between each ink roller should be adjusted according to the paper sizing state, that is, the gap between each ink roller should be adjusted to control the printing plate The amount of ink. It can be seen that the absorption performance of the base paper should be tested when the base paper enters the factory, and the printing slotting machine and the ink matching personnel should be given an absorption performance parameter of the base paper, so that they can match the ink and adjust the equipment. And adjust the ink viscosity and PH value according to the absorption state of different base papers. Aloe Vera Skin Care,Aloe Vera Face Pack,Natural Aloe Vera Gel,100 Pure Aloe Vera Gel Zhejiang Laizhen Biotechnology Co., Ltd. , https://www.laizhen-bio.com
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