Pressure is one of the important conditions of offset printing and embossing processes. Moderate printing pressure is also an effective process and technical measure to ensure the normal production and improve the printing quality of products. However, if the operating technical measures are not in place and the printing pressure is not suitable, it will cause some printing failures and must be paid attention to. 1. Overprint fault caused by excessive printing pressure When the surface of the roller's teeth is worn, deformed, and the pressure of the teeth is uneven or insufficient, the printed sheet is likely to slip during imprinting after entering the teeth, resulting in inaccurate product overprinting. Especially in the case of a large ink receiving area on the printing plate and a large viscosity of the ink used for printing, the performance of the product printing failure is more prominent. The main reason is that the printing pressure is obviously heavier, and after reducing the printing pressure, the ink color and imprinting effect are not satisfactory. In this regard, the solution is to replace the severely worn teeth with new teeth; adjust the deformed, uneven bite pressure and insufficient bite to adjust the entire tooth surface to bite the edge of the paper; the ink viscosity If it is too large, use additives to moderately dilute and reduce the viscosity of the ink; for printing special color inks, the ink hue can be properly adjusted to make the printing ink layer thinner, which can reduce the viscosity of the ink and meet the requirements. Printing hue requirements. In addition, appropriate reduction of printing pressure and adjustment of printing pressure are based on the fact that the ink layer on the printing plate surface is evenly transferred to the printed sheet. Of course, the uniformity of the thickness of the liner is the basis and a prerequisite. These operating techniques are well controlled, so the problem of inaccuracy of overprinting caused by the clenching of the paper and the teeth is not solved. 2. Ink stick marks caused by uncomfortable printing pressure When there is a serious problem of roller bearing wear, due to excessive roller yield, it causes sliding friction on the surface of the roller and causes ink streaks to appear. This is a situation. In another case, due to the use of a hard liner, the ink stick is caused by the occurrence of sliding phenomena during the imprinting process. The third situation is that the roller gear is seriously worn, the center distance of the roller is adjusted too large, so that the backlash of the gear is too large, so that the gear trembles after the roller is pressed, and the sliding friction on the surface of the roller causes ink sticks. The fourth situation is that the pressure between the plate cylinder and the blanket cylinder is too high, so that the blanket is pressed, forming a large frictional sliding, which causes the longitudinal deformation of the grid dots to expand and cause ink stick marks. For the above situation, the roller bushing should be replaced; the characteristics of the packing material should be adjusted; the center distance of the roller should be reduced so that the gear backlash is less than 0.1mm; the thickness of the pad should be set according to the requirements of the equipment to avoid the occurrence of excessive pressure To prevent ink sticking. 3. Ghost failure caused by uncomfortable printing pressure When the pressure between the rubber cylinder and the impression cylinder is too large, the displacement of the rubber cloth will increase accordingly. Therefore, the ink layer cannot be restored to its original state in time immediately after the transfer of the ink layer during the imprinting process. At this time, it is easy to produce a small amount of disparity, forming a ghost mark. In this regard, it is necessary to reduce the pressure on the cylinder and reduce the expansion and contraction coefficient of the blanket during imprinting to prevent ghosting failures. In addition, for rubber blankets that have been aged for a long time, they should be replaced with new blankets for printing to eliminate printing ghosting failures. Unsuitable printing pressure in the offset printing process can cause ghosting failures, as does the relief printing process. When the embossing process uses multi-layer glued wood as the printing base pad to print large-area plate products, due to the uneven bottom and poor solidity, the printing plate flutters during the imprinting process and causes printing ghosting failures. In this regard, the elimination measures are that the bottom pad should be flat, and the four sides of the bottom pad should be planed into a straight edge and a right angle state, so that the bottom surface is closely attached to the plate after the plate is tightened, and the ghost failure caused by the "overhang" of the plate is eliminated . 4. Dirty and pasted plates caused by excessive printing pressure 5. Ink color hair flower caused by uncomfortable printing pressure When the liner is uneven or the pressure is uneven or insufficient, during imprinting, poor contact may occur between the printing plate and the rubber, between the rubber cylinder and the impression cylinder, or between the printing plate and the package liner (relief process), affecting the ink layer on the plate surface. Even and full transfer, which causes the ink on the plate with insufficient pressure to become pale and flowery. In order to avoid this unfavorable situation, the printing "three flat" process technology should be well closed. The printing plate and the inking roller should be flat, and the bottom pad of the printing plate should be flat; the printing plate should be flat with the blanket cylinder or liner (embossing) , The blanket or blanket should be leveled; the impression cylinder and the rubber cylinder should be flat, and the surface of the impression cylinder should be protected to prevent the damaged deformation from losing flatness; maintaining uniform and sufficient printing pressure is to eliminate the ink color of the printed product. Effective measures. In short, printing pressure is the basis of product quality. Only by carefully controlling the printing operation technology, scientifically and rationally adjusting and handling various factors that affect the pressure, can the printing quality of the product be ensured. 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When the printing pressure is too high, the friction of the blanket surface against the printing plate surface must be increased, so that the plate surface sand is damaged by abrasion, the hydrophilicity of the blank area changes, the ink is attached and transferred to the printed product. The situation is a dirty version. In addition, when the printing pressure is too high, the elastic deformation value when the rubber is compressed is also large, and the transfer of the imprint is also prone to deformation, especially when printing dots and small text, the deficiencies of paste edition often occur. If it is a letterpress process, this kind of situation is more obvious. Therefore, in order to prevent the occurrence of dirty and pasted plates, the printing pressure must be accurately adjusted. Control liner thickness and roller center distance according to equipment specifications.