Requirements for the most popular flexographic pri

Relevant requirements for flexographic printing

1 Printing plate

4. Service life: the surface damage of rotating friction is much smaller than that of sliding friction. Corrugated cardboard has a certain elasticity in the direction perpendicular to the paper surface, which has a cushioning and shock absorption effect on the packaging. This is the main reason why corrugated board is widely used to make packaging boxes. However, this elasticity brings certain difficulties to printing. In order to adapt to the flexible substrate and make it have good ink transfer, the printing plate must be softer than the printing plate used in general flexographic printing. Except for particularly fine prints, the plate hardness of most corrugated boards is 30 ± 5 shore

2. Printing machine

corrugated board flexographic printing machine has a variety of specifications, and the small one can print 610mm × 1620mm corrugated board, up to 2030mm large × 4830mm。 Because the printing format is large, the plate cylinder is also large. Generally, the plate cylinder cannot be disassembled. When printing a new job, the flexible plate on the plate cylinder can be replaced

you can see from the oil spill and other outlets

3 Ink

the vast majority of corrugated cardboard is printed with water-based ink. This is because: first of all, the text or simple patterns printed on corrugated board do not need to be very shiny (only for the quality requirements of some cartons), and water-based ink can meet the quality requirements of printing. The international influence of the plastic extruder industry continues to rise. Secondly, corrugated board is a loose fabric with strong water absorption. After coating with water-based ink, its drying method is mainly osmotic drying, with fast drying speed, and there is no need to set a drying device. Thirdly, water-based inks have less pollution and low cost

4 The ink transfer roller

the ink transfer roller is the core of the flexographic printing machine. It has many types, such as chrome plated roller, ceramic roller, etc. no matter which one, its structure, function and principle are the same

the surface of the ink transfer roller is provided with a concave groove line for controlling the ink transfer volume during printing. The surface grooves of the ink transfer roller are regularly arranged to form a concave hole. The ink transfer performance of the ink transfer roller is related to the number of grooves, the shape of holes, and the arrangement of holes

the function of transferring ink is shown in the figure: when the metal ink transfer roller (2) after squeezing the ink on the surface of the roller by the ink scraping rubber roller (7) contacts the flexographic plate (3) pasted on the plate roller (6), most of the ink stored in the hole is evenly transferred to the surface of the flexographic plate (3), and printed on the corrugated box board (5) through the plate roller (6). The ink transfer printing system on flexographic printing machine is composed of metal ink transfer roller, ink scraping rubber roller and plate roller. Every time the metal ink transfer roller runs, it realizes a complete functional process of metering, ink storage, ink homogenization and ink transfer

due to the late start of corrugated box flexographic printing in China, the printing technology level needs to be improved. Therefore, some areas need to be improved