At present, the commonly used printing methods of self-adhesive paper/thermal paper are lithographic printing, letterpress printing (including flexo printing) and screen printing. The machine structure is divided into three types: round pressing, round pressing and flat pressing, and qz. Stamped form. Products with a slightly larger printing layout, such as posters, trademarks, etc., are generally printed by offset printing machines with circular or circular flattening structure, and letterpress automatic printing machines can obtain satisfactory results in product quality and printing efficiency. The small-format multi-imposition structure, and the trademarks and label products that require die-cutting, lamination, and bronzing, are most suitable for printing with letterpress self-adhesive paper/thermal paper label printing machines.
Self-adhesive paper and thermal paper printing process
This type of machine has the characteristics of integrating ink distribution and printing mechanism of glue and convex printing machines. Foil, lamination, die-cutting, rewinding offcuts and slitting. The machine can use metal plate and resin plate for printing. Due to the building block structure, certain functional parts can be added or removed flexibly and conveniently according to the characteristics of the printed parts. The paper feeding structure and delivery structure of the machine are basically similar to those of the flexographic printing machine. The difference is that a mechanism that can control the paper stepping printing is added during the entire traveling process. This mechanism requires strict time control and positioning control to avoid Ensure overprinting is accurate. Products that require a thick layer of printing ink can be printed by a screen printing machine. The printing ink is bright in color and has high color brightness. It is an ideal printing process for posters and large-area trademarks. What is the principle of thermal paper?
Analysis of the relationship between printing equipment structure and product quality:
When the roll paper self-adhesive paper/thermal paper is printed, the direction of the paper is different from the general printing method. It realizes the overprinting by the axial jumping movement, that is, several sets of printing plates are installed on the plate cylinder at the same time. Each time the self-adhesive paper/thermal paper jumps on the embossing platform, the plate cylinder rotates back and forth in the horizontal direction, and one color can be printed. Then, to print the overprint of several colors, overprint the label of the layout, and the self-adhesive paper/thermal paper must move the corresponding number of times on the platform to complete the overprinting of all the layouts. The design of this machine structure simplifies the structure of the equipment and reduces the size of the machine. However, due to the short printing stroke, the printed product is not easy to dry, which is not conducive to the completion of large-area wet-press wet overprinting, and is only suitable for small-area overprinting. or overprint.
The letterpress automatic printing machine with circular flattening or circular pressing structure has high printing pressure, full and uniform ink color, and is more suitable for printing large-format self-adhesive paper/thermal paper products. Well, it is beyond the reach of the multi-color self-adhesive paper/thermal paper printing machine with a flat-flat structure. From the point of view of the embossing structure, the printing quality of the model with a circular flattening structure is obviously better than that of the flattening machine, especially in terms of printing solid layout, the good effect of uniform and thick ink layer can be achieved. On the other hand, the self-adhesive paper/thermal paper machine with a flat and flat structure, printing a large-area solid layout (printed product) is likely to present an "oily" ink layer, and the printing quality is not satisfactory. Through the analysis and comparison of the product printing process effect, we can find that the printing quality and process effect are satisfactory.
In the production practice process of letterpress printing machine, I also have a deep understanding of the printing process of self-adhesive paper/thermal paper. We originally used the self-adhesive paper/thermal paper machine with a flat-flat structure to print large-area solid layout products, such as Labels for TV sets and other electrical products are often prone to "oily" ink layers on the printed layout, which are very unsatisfactory and really annoying. Later, the author switched to a letterpress automatic printing machine with a circular flattening structure to print this type of product. Due to the sufficient and uniform printing pressure, and the good inking and ink distribution structure, the printed product has a uniform ink color, thick, high brightness, and the ink layer is regenerated. There is no "oil flower" shape, and the printing quality effect of the product is deeply satisfied by users.