Some problems that should be paid attention to in

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Some problems that should be paid attention to in printing coated paper coated paper is an important material for packaging and decoration printing process. The printing quality of its products largely depends on the advantages and disadvantages of the material itself and the degree to which the operator knows the characteristics of the paper. In other words, to print coated paper products well, corresponding technological measures must be taken according to the characteristics of the paper. Therefore, it is necessary to know and understand the technological requirements of coated paper

the varieties of coated paper are generally divided into single-sided light and double-sided light according to the difference between filling and calendering. From the nature of the coating, it can be divided into casein coating. So coated paper is also called coated paper. Due to the defects in the process of some domestic coated paper, it is easy to produce different degrees of de dusting and stretching variation, especially the curling defect of single-sided coated paper, which affects the accuracy of overprint. Improper operation of some techniques of printing coated paper is also prone to sticky dirt (over bottom), chalking, slow drying, Star color is not bright, etc. Therefore, the following problems should be paid attention to

1. Before each batch of coated paper is put into use, a series of printing suitability problems involving smoothness, pH, absorption, dryness, scalability and surface bonding strength of the paper shall be tested and analyzed, and then corresponding process measures shall be taken according to the characteristics of the paper, such as adjusting the viscosity, fluidity, dryness and anti sticking measures of the ink, so as to achieve standardized and scientific production, Prevent printing defects

2. It is necessary to check the pad technology and printing pressure adjustment to ensure that the printing ink layer is uniform and bright. The printing pressure of coated paper should be uniform and appropriate. Excessive pressure is easy to cause poor powder dropping, and it is easy to cause unclear dot marks and increase the wear of printing plate. On the contrary, it is easy to cause weak dot imprinting, and blindly increase the ink layer to make up for the layout blooming caused by insufficient pressure. In that way, it is easy to produce sticky, slow drying, poor overprint and other adverse consequences. Therefore, the pressure of the coated paper should be uniform and appropriate. The lining should be made of neutral and hard materials

3. Use coated paper to print trademarks and packaging products, often with light color as the background color, which is made by overlapping and overprinting. In this way, improper printing process can easily lead to some problems and affect the quality. Therefore, when preparing the base color ink, we should try to use heat-resistant and light-resistant ink, and the diluent should be prepared with bright paste. In this way, the base color can be put into the final printing effect, so as to prevent the ink layer from being damaged by the friction of the first printing of the base color

4. Due to the smooth surface of copper plate and poor ink absorption ability, the field version with large layout should be printed with "deep ink and thin printing" as much as possible. That is to say, the ink phase should be properly deepened so that the ink layer can be correspondingly or thinner when printing with the goal of mastering the key core technology, which can not only meet the printing color phase requirements, but also reduce the chance of over bottom imprinting and prevent color stacking printing. In addition, due to the poor adhesion of the paper, the printed ink layer is sometimes easy to decolorize due to powder dropping. Therefore, No. 19 resin oil can be used as the ink mixing oil for the first color printing. In order to make the laminated ink layer bright, you can add some light oil and dry oil in the ink. Wire rod and profile (Anyang Iron and Steel Group, Xinpu and other companies) machining railway equipment (Anyang railway equipment, Lida comprehensively analyzed the core issues of railway equipment, Northern Railway equipment, Hongyuan wheel and other companies that car enterprises pay attention to lightweight)

5. Due to the large amount of coating, coated paper often encounters the phenomenon of de dusting and black shadow on the printed page in the printing process. In this case, pay attention to check whether the plate mounting process is operated. For example, whether the printing plate is padded too heavily, because if the paper surface pressure is too large, it is easy to crush the coating powder on the surface of the coated paper, resulting in de dusting and black shadow spots. In addition, it is also necessary to check whether the ink viscosity is appropriate. If the printing ink layer is too thick and sticky, it is also one of the reasons that cause the paper surface to drop powder and accumulate the layout. In this case, it is necessary to consider using auxiliary materials to adjust the ink quality, and the above quality problems can be better overcome

6. Control the anti sticking technology of coated paper printing. Coated paper has weak ink absorption and relatively smooth back. In this way, printing pages with large ink receiving amount or multi-color overprint are prone to sticky and dirty problems. Therefore, anti sticking measures should be taken to overcome them. For example, a proper amount of anti sticking agent should be stirred with gloss oil to make it liquid, and then added to the oil and ink to mix well. A better anti sticking effect can be achieved during printing. However, the amount of anti adhesion agent should be reasonably controlled, which should not exceed 4%, so as to avoid such undesirable defects as ink emulsification, printing ink layer blooming and ink layer gloss reduction

in a word, as long as we master its characteristics and correctly control the printing and operation skills, 6 According to the structure principle, it can be divided into electronic, hydraulic, mechanical and servo experimental machines; The technology can not only improve the printing efficiency, but also effectively ensure the printing quality

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