Metal printing technology

With the continuous improvement of the people’s living standards, the use of metal packaging has become more and more popular. As a traditional printing method, metal printing has undergone tremendous changes. In the coming period, metal printing inks, printing methods, printing equipment The development will have the following trends.
Metal printing inks Metal printing inks are mainly composed of pigments, binders, fillers and auxiliary agents. In addition to the printability of general offset inks, metal printing inks should also have impact resistance, strong adhesion, heat resistance, light resistance, and resistance to cooking. Other characteristics.
Due to the impermeability of the surface of the metal printing material, dot gain tends to occur. Compared to paper printing inks, high-viscosity inks should be used for metal printing lithographic printing. The surface of the metal is poor in water absorption, and too much wetting water on the plate will easily cause the emulsification of the ink. Therefore, the water and ink balance on the plate should be achieved by controlling the thickness of the water film on the plate and the amount of ink applied.
In the metal printing, in order to improve the adaptability of the post-press processing, and to make the surface of the print have a certain degree of gloss, the glazing treatment should be performed before the printing ink is not completely dried to form a uniform and smooth coating film to avoid bleeding. phenomenon. At the same time, the metal printing ink should have a certain hardness and toughness, can not change its properties when repeated heating, the base color coating and coating oil should have good adhesion.
UV glazing and its curing UV varnish are mainly composed of photosensitive resin, reactive diluent, photoinitiator and additives. UV curing is under ultraviolet irradiation, the photoinitiator in the component absorbs the light energy of ultraviolet light, generates free radicals through the excited state, and initiates the polymerization reaction, so that the free-radical-polymerized acrylic glazing coating is cured and formed into a film. Since the metal surface is a non-absorbent surface, the post-printing drying problem is one of the main technical problems in metal printing. Instantaneous drying with ultraviolet irradiation not only accelerates the drying of the varnish but also contributes to environmental protection.
UV curing has the characteristics of rapid curing and low temperature curing: the film is bright and smooth, and the refraction effect produces a strong sense of text and a more vivid color; it helps to maintain the same color and solves the problem of solvent-based glazing coatings due to temperature and humidity. Adhesion caused by the change; After drying, the film surface is firm, with good heat resistance, cold resistance, water resistance, abrasion resistance and protection; printing time is short, production efficiency is high, occupation of the market is small; it is environmentally friendly and improves the working environment. .
UV curing light sources generally use high-pressure mercury lamps or metal halide lamps. For different UV light sources, the wavelength range of the emitted light is different, and the spectral energy distribution in the waveband is also different. Solving the problem of UV glazing and UV light source matching will help speed up the speed of varnish curing, increase energy efficiency, and reduce the company's production costs.
The use of chamber-type scraper and anilox roller devices to quantify glazing and UV drying are the development trends of foreign metal printing, and the development of low-temperature drying UV varnishes is used to save energy and increase productivity.
Metal Plates Non-Horizontal Plates Offset Metal Plates Horizontal Plate Offsets are lithographic printing methods that use an ink-repelling silicone rubber layer as a blank part of the printing plate and do not require dampening. Due to the non-absorbing properties of the metal plate, the elimination of the wetting water is more advantageous for the printing of the metal plate. Therefore, no horizontal offset printing has been promoted and applied in foreign metal plate printing.
The metal plate horizontal offset printing press is an offset printing press which uses a metal plate as a printing material and a horizontal printing plate. It is mainly composed of a plate cylinder, a blanket cylinder, an impression cylinder, and an inking device. The printing plate adopts a positive-type horizontal printing plate or a negative-type horizontal printing plate. The layout of the printing plate is lower than the blank portion, which not only improves the glossiness of the printing plate, but also facilitates the drying of the ink layer.
The development direction of metal printing equipment (1) The use of intelligent tooth transfer device, double-diameter impression roller and transfer roller, can extend the transfer time of the caries, to ensure accurate transfer of printed sheets at the highest speed, to ensure the smooth passage of printed sheets.
(2) Automated feeding, fully automatic quick plate change, quick ink change and ink roller automatic clutch, automatic cleaning plate and blanket, and impression cylinder, increase the automatic setting of metal sheet size functions to improve the automation of metal printing equipment degree.
(3) Adopt print quality control and modular open system to automatically set and control ink and dampening water, properly adjust printing pressure, realize register adjustment of circumferential, transverse and diagonal lines, and improve multi-color register accuracy And the accuracy of register accuracy. Data exchange between pre-press, printing and post-press processing integration and management levels to monitor the production of printed iron.