Some problems in the printing of cigarette labels

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Some problems in the printing of cigarette labels

our company's main business is the printing of cigarette labels. Here are some problems and corresponding solutions that have occurred when using multi-color offset printing machines to print cigarette labels, which are listed for reference by peers

1. printing coated paper

coated paper is often used in the inner box of flexible packaging cigarettes. This kind of paper has a lot of paint on the surface, so the paper is compact, with poor elasticity and compressibility, and low ink absorption, so the pressure should not be too high in printing: the ink color of spot color ink can be slightly adjusted to be deeper, while the ink volume should be slightly smaller during printing, and the powder spraying should be slightly larger to prevent the back from sticking dirty. The side paper aligning mechanism on the receiving board should not be too tight, especially when the edge pattern of the printing sheet is a large area of the field, we should pay more attention to it. We prefer that the paper stack is a little uneven, and do not cause the printing to be sticky and dirty because of too much squeezing

when printing gold and silver ink, it may cause a pile of blanket due to the high viscosity of gold and silver ink. At this time, clean the blanket as soon as possible, otherwise it is easy to damage the graphic foundation of the printing plate. In addition, add an appropriate amount of gold blending oil to dilute the ink. The coating layer of some papers is not firmly combined with the base paper, which is very easy to remove powder. At this time, note 4. The swing radius of the pendulum: r280mm. If you are careless, you need to replace the gold plate

when overprinting thin paper, pay special attention to the positioning position of the side pull gauge, so that both sides of the paper can be caught by the paper teeth as far as possible. If there is a long section of paper that is not effectively controlled by the paper teeth, there will be a slight displacement of the trailing part of the print, resulting in ghosting, and the print will wrinkle in serious cases

2. Printing whiteboard

cigarette cartons mostly use whiteboard. When printing this kind of paper, pay attention to that the printed pictures and texts should not be scratched by the paper transfer roller. It can be solved by adding an elastic pad for die cutting on the paper transfer drum. First click a registered print sheet into the machine, then take a piece of elastic pad, tear off the protective paper, apply glue on the non sticky side, and stick it on the blank area of the print sheet, and then click the machine to make the elastic pad adhere to the paper transfer roller, so that the elastic pad can separate the print from the paper transfer roller during printing, so as to avoid scratches on the print

this method can also be used to prevent scratches when printing white cardboard flip Hard boxes

this kind of thickness test item is relatively simple. Don't adjust the tooth opening time of the tooth opener too early during the paper receiving (especially the new machine), otherwise the printed matter may fall down before it arrives, and contact the printed matter on the paper receiving pile. Because the printing sheet will continue to move by inertia and the rotating thrust of the suction wheel, it is easy to scratch the prints on the receiving stack. This kind of scratch can never be found by sampling inspection in the process of printing p= and may have suffered heavy losses when it is found by post process inspectors

3. printing gold and silver card paper

many high-end cigarettes are undoubtedly huge business opportunities. Silver card paper and gold card paper are used. This kind of paper is very fragile and easy to scratch. You must handle the paper with care; The paper delivery suction nozzle should also be adjusted as high as possible, otherwise the paper delivery suction nozzle may scratch the paper jam when returning the paper to the paper receiving roller; The side paper aligning mechanism is best adjusted to a non moving position to avoid scratching the print due to squeezing

4. Printing large-area field

cigarette packaging often uses large-area field in design. When the graphics and texts of this kind of printing plate fall out, you can scratch the aluminum base of the printing plate with a knife, and then apply a small amount of 502 glue to make up for it. The effect is remarkable

sometimes the sand particles in the paper are transferred to the inking roller, which will scratch a long mark in the circumferential direction on the printing plate. Generally, the problem cannot be solved only by changing the printing plate. When the impression is obvious, the inking roller must be removed and rubbed with fine sandpaper dipped in water, so as to wipe out the sand embedded in the depth of the rubber roller

as for others, such as pasting and ghosting. Wrinkle, overprint inaccuracy, ink bar and other issues have been discussed in a large number of documents, and will not be repeated here one by one

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