Seven, printing quality failure caused by bad ink 1. Insufficient ink drying. When the ink is dried too fast, it will cause the early conjunctiva phenomenon of the ink layer, and the ink may be unevenly colored and the paste may be caused to malfunction when printing. This is mainly due to the excessive use of dry oil in the ink and the excessive drying of air humidity. For the above reasons, the ink is crusted on the ink roller, and an appropriate amount of dry oil can be added to suppress the drying speed. 2. The discoloration of ink on the printed page causes poor coloration. Due to the poor pigment performance of inks, inferior organic pigments are used, or heterogeneous pigments are mixed in, so that a chemical reaction causes discoloration. This ink is not suitable for color printing. 3. The ink on the printed page fades. If too much ink is added to the ink or the detackifier is added, and the water content of the plate is too large, the sensory quality of the printing plate graphic part will be reduced, and the ink color of the printing product will appear faint. This should be renewed. To adjust the ink, that is, to tighten some of the original ink in the thin ink, so that the concentration of the ink is increased; reduce the moisture of the printing plate to improve the coloring power of the ink. 4. The ink on the back of the dirty print. When the ink layer of the printing plate is thick, or the amount of the auxiliary agent is not appropriate when adjusting the ink, the drying speed of the ink is slowed down, so that the phenomenon of sticky product is easily caused, and a certain amount of desiccant and anti-adhesion may be added into the ink. Agent to eliminate blotting (dirty) malaise. 5. The layout ink lacks gloss. Due to the poor quality of the oil varnish, the insufficient amount of varnish, and the excessive water content on the plate, the printing ink layer will lack luster. For color printing products, bright ink can be used for printing, or an appropriate amount of brightener can be added to the ink to increase the gloss of the printed ink layer. Eight, the printing ink layer is not firmly attached to the fault phenomenon The printing ink layer can not be adhered firmly and can be divided into the following types: the print with insufficient abrasion resistance is not strong; the print with weak light fastness is not strong; and the print with insufficient chemical resistance is not strong. 1. Due to the overabsorbed surface of the printing ink, the excessive binder in the printing ink layer penetrates into the capillary structure of the substrate, resulting in the pigment in the printing ink layer not having enough binder to consolidate the film and protecting it. The phenomenon of discoloration of the imprinting powder on the rub. 2. As the semi-finished products are processed in the post-printing process, such as the light machine, the folder-gluer, and the cover machine, due to the presence of friction, the printing ink layer of the printed product appears discoloration. 3. Due to the fact that the printing ink layer is not light fast, it is prone to discoloration under strong light or UV process conditions. 4. Due to lack of chemical resistance of the printing ink layer, the color of the imprint or the imprinting is not firm. When the printed product is in contact with packaged acids, alkalis, salts, soaps, greases, alcohols and other chemicals, fading occurs easily. Nine, to prevent printing quality failure of a number of technological measures 1. Always stir the ink inside the ink fountain and pay attention to increase the ink in the ink fountain. Color inks are often formulated from a wide range of colors. Due to the different nature of pigments, binders, and fillers in different inks, it is inevitable that different substances in the ink will be precipitated and suspended. Once this state is apparent, Existence will inevitably result in the variation of the ink color of the printed product. Therefore, the ink in the ink fountain should be frequently used in the printing process to prevent the ink from being precipitated and suspended to ensure that the ink color of the product before and after printing is consistent. In addition, due to the reduction of the amount of ink in the ink fountain, it is easy to make the gap between the ink fountain steel sheet and the transfer iron roller smaller, so that the ink output amount is reduced, and the ink color of the print product is lightened. In order to avoid this from happening, it is also necessary to pay attention to adding ink regularly during production so that a certain amount of ink is always maintained in the ink fountain. 2. The adjustment of the local ink shade in the lateral position of the print. Due to different layouts of printed products, such as horizontal layout of a section of text, webbing, and lines, the amount of ink suction is relatively small, and the corresponding ink steel adjusting screw can be screwed in, so as to reduce appropriately. The amount of ink delivered to this site. If the position of a certain section of the horizontal layout is based on the field or the plate, the amount of ink is relatively large, the corresponding adjustment screw should be twisted outward to increase the amount of ink, so that the entire color of the ink remains uniform and the problem of color printing is prevented. The emergence of. 3. Full-size ink shade adjustment. Ink fountain ink to increase or decrease the total amount of ink, there are two ways to adjust, the first by adjusting the ink fountain steel and transfer ink (to ink) iron roller gap to achieve; second is to adjust the transfer of iron roller Turn the arc to achieve the size. In the case of a thin ink, it is not appropriate to adjust the gap between the steel sheet and the iron roll so as to prevent the ink from causing ink unevenness or color miscellaneous defects. When adjusting the amount of ink, the rotating arc of the transfer roller should be controlled within 1/2 of its adjustment range. This can allow the ink to be flexibly adjusted during the printing process to variably variate to prevent ink from being printed. Inconsistent ink. 4. Correctly adjust and use the ink to prevent the production of color differences. Scientific and reasonable use of ink is an important part of guaranteeing the quality of printed ink. The ink of printed color products is too thick or too thin, which is not conducive to uniform ink and ink. In general, when the temperature is low, the ink is thick and its flowability is poor, which may easily result in poor transfer and uneven distribution. In this regard, according to the characteristics of the printed product, an auxiliary agent should be used to appropriately dilute the ink to keep it. Good fluidity and transfer effect to keep ink uniform. If the ink is too thin, the ink will fade. Adjustment of ink flow, should fully consider the characteristics of the printer speed and ink structure, if the printer speed, ink path length, ink roller and more, because the friction coefficient is large, the ink is easy to thin and fade, so deployment Ink should fully consider the above situation and reasonably adjust the printability of the ink. In addition, when blending color and double color inks, we should try to avoid mixing the inks with large specific gravity, so as to avoid the ink on the ink fountain caused by the difference in the specific gravity of the printing, resulting in “layered†(precipitation and suspension) phenomenon causing the printing color difference. . 5. Turn off the process technology to prevent the production of color differences. When printing, if the operation and technical measures are not in place, frequent stoppages occur in the production process, which is very likely to cause printing and color difference. In order to avoid this situation, first of all, we must pay attention to the reasonable maintenance of the machine. We must always maintain the Feida parts and the air pump to maintain a good use of mechanical parts, so that the air flow is smooth and unobstructed. According to the thickness and size of the printed sheets, feeders, air pumps, and parts related to the transport of paper should be adjusted to ensure the normal transport of printed sheets. Third, the printability of the white paper must be adjusted as necessary, for example, by hitting the cardboard. Shake and knead the processing operation, so that the cardboard to achieve the effect of transmission, in order to eliminate the adhesion and adhesion phenomenon, and to achieve a flat cardboard, in order to facilitate the smooth transport of paper, while better avoid empty sheets, suction paper And the occurrence of skew failure; Fourth, we must put a good pile of paper operation technology, the paper pile is not smooth, should take measures to carry out flat processing, so that no significant difference in height. Through these process and technical measures, the control is checked so that the paper feeding is maintained in order to prevent printing chromatic aberration caused by parking. In summary, the quality problems of white board printing are various, there are a variety of bad factors, and there are several defects, as long as we carefully analyze and summarize the experience of the production process, put a good printing process technology and operating machine brush Off, not only can better prevent the occurrence of printing quality problems, improve product quality, but also can effectively improve production efficiency. Source: Qingdao Runhai Packaging Materials Co., Ltd.