How does the curing process of qinghua offset printing ink black affect the shrinkage of different printing materials?
Publish Time: 2025-05-07
In the printing industry, qinghua offset printing ink black is widely used in various printing materials due to its unique color performance and good printability. Its curing process has a significant impact on the shrinkage of different printing materials. In-depth understanding of this impact will help optimize the printing process and improve the quality of printed products.For paper printing materials, the thermal effect and chemical reaction during the curing process of qinghua offset printing ink black will affect the shrinkage of the paper. During curing, the volatile components in the ink gradually evaporate, and at the same time, the resin and other components undergo cross-linking and curing reactions, releasing a certain amount of heat. Paper has a certain degree of hygroscopicity, and its water content will change with the ambient humidity. The heat generated during the curing process may cause the local moisture of the paper to evaporate, resulting in shrinkage of the paper fibers. Different papers have different fiber structures, tightness and sizing degrees, and their sensitivity to heat is also different. For example, the coating on the surface of coated paper is thicker, and the heat conduction is relatively slow, but the difference in thermal expansion coefficient between the coating and the paper substrate may cause slight curling or shrinkage of the paper after curing; while the fiber arrangement of offset paper is relatively loose, and the fiber shrinkage may be more obvious under the action of curing heat, which will affect the overprinting accuracy and dimensional stability of the printed product.As a special printing material, gold and silver cardboard is covered with a metal layer on its surface. When qinghua offset printing ink black is cured on gold and silver cardboard, the thermal conductivity of the metal layer will accelerate the curing speed of the ink, and will also affect the shrinkage of the paper substrate. The bonding force between the metal layer and the paper substrate may change during the curing process. If the curing process is not properly controlled, the stress generated by the curing of the ink may cause delamination between the metal layer and the paper substrate, which will affect the overall shrinkage rate of the paper. In addition, the metal layer of the gold and silver cardboard may be affected by thermal stress during the curing process, and may undergo slight deformation, which will also indirectly affect the shrinkage of the paper and cause dimensional deviations in the printed product.Laser paper has a unique optical effect, and its surface has a special laser pattern layer. When qinghua offset printing ink black is cured on laser paper, the thermal expansion coefficient of the laser pattern layer may be different from that of the paper substrate and the ink layer. During the curing process, the mismatch in thermal expansion between different materials will cause internal stress in the laser paper, which will cause shrinkage. Moreover, the structure of the laser pattern layer is relatively complex. The penetration and curing degree of the ink during the curing process may have a certain impact on the pattern layer, change its optical properties and physical structure, and further affect the shrinkage rate of the paper.When printing on ordinary plastic materials, the thermal effect of the curing process of qinghua offset printing ink black has a more significant effect on the shrinkage of the plastic. The thermal expansion coefficient of plastic materials is usually large. The heat released by the ink during curing will increase the local temperature of the plastic surface, causing thermal movement of the plastic molecular chain, thereby causing shrinkage. Different types of plastic materials, such as polyethylene, polypropylene, etc., have different molecular structures and thermal stability, and respond differently to curing heat. Some plastics may deform, warp, etc. during the curing process, which seriously affects the quality and appearance of the printed product.The curing process of qinghua offset printing ink black has many effects on the shrinkage rate of different printing materials. In actual printing production, it is necessary to reasonably adjust the curing process parameters, such as curing temperature and time, according to different printing materials, so as to reduce the impact of the curing process on the shrinkage rate of the printing material and ensure the quality and dimensional stability of the printed product.
