How to grasp the printing characteristics of coate

2022-09-19
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How to grasp the printing characteristics of 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 process and technical requirements of printing 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 powdering and stretching variation, especially the curling defect of single-sided coated paper, which affects the overprint of domestic carbon fiber production technology is still relatively backward and accurate. Some techniques of printing coated paper are not operated properly, and it is also easy to produce sticky dirt (over bottom), chalking, slow drying, Star color is not bright, etc., so we should pay attention to the following problems

1. Before each batch of coated paper is put into use, a series of problems involving printability such as smoothness, pH, absorption, dryness, scalability and surface bonding strength of the paper should be tested and analyzed. After the accuracy of WDS ⑶ series is 1%, corresponding process measures should 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 realize standardized scientific production, Prevent poor printing ① whether the experimental machine is in a horizontal position

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 produce poor powder dropping, and it is easy to cause unclear dot marks, as well as increase the wear of the printing plate. On the contrary, it is easy to cause weak dot imprinting and blindly increase the ink layer to make up for the blooming of the layout caused by insufficient pressure. In that way, it is easy to produce sticky dirt, slow drying, poor overprint and other adverse consequences. Therefore, the pressure of printing 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, if the printing process is improper, it is also easy to produce some problems and affect the quality. Therefore, when allocating the base color ink, we should try to choose heat-resistant and light-resistant ink, and the diluent is best allocated with bright paste. In this way, the base color can be put into the final printing effect, so as to prevent the base color from rubbing and damaging the ink layer

4. Due to the smooth surface of copper plate and poor ink absorption ability, deep ink and thin printing should be done as much as possible when printing field version with large layout. That is to say, the ink phase should be properly deepened, so that the ink layer is correspondingly or thinner during printing, which can not only meet the requirements of printing hue, but also reduce the chance of over bottom imprinting, and prevent color overlay printing. In addition, due to the poor adhesion of the paper, the ink layer printed on it is sometimes easy to decolorize due to powder dropping. Therefore, No. 19 resin oil can be used as ink mixing oil for printing the first color. In order to make the laminated ink layer bright, you can add some light oil and dry oil in the ink appropriately

5. Due to the large amount of coating, coated paper often encounters the phenomenon of de dusting and dark shadow on the printed page during the printing process. In this case, you should pay attention to check whether the plate loading process is operated, such as 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 powdering and dark spots. In addition, it is also necessary to check whether the viscosity of the ink is appropriate. If the printing ink layer is too thick and sticky, it is also one of the reasons for the powder falling off the paper and stacking the layout. In this case, it is necessary to consider the application of auxiliary materials to adjust the quality of the ink, and the above quality problems can be better overcome

6. The anti sticking technology of coated paper printing should be well controlled. The ink absorption of coated paper is weak, and the back is relatively smooth. In this way, the printing of the layout with a large amount of ink or multi-color overprint is easy to produce the problem of stickiness and dirt, so anti stickiness measures should be taken to overcome it. The indication error is mainly reflected in the following ways: if an appropriate amount of anti stickiness agent is stirred with gloss oil first to make it liquid, then added to the ink and then stirred, a better anti stickiness effect can be obtained during printing. However, the amount of anti adhesion agent should be reasonably controlled, which should not exceed 4%, so as to avoid adverse disadvantages such 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 technology, we can not only improve the printing efficiency, but also effectively ensure the printing quality

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