What is the Flexographic plate? Points and precautions!

Compared with traditional resin letterpress and offset printing plates, flexographic plates are a kind of photosensitive rubber or resin type printing plates, which have the characteristics of softness and flexibility. Therefore, in the printing production process, flexo plates due to their different characteristics often appear flexo plate resistance rate is low, difficult to control the operation of the plate, the quality is not stable, easy to block the plate, the high cost of plate making, low number of lines of screening and other phenomena, so that the printing workers are troubled. Understanding and familiar with the characteristics of the flexographic plate to eliminate these phenomena will be helpful.

Flexographic printing can be printed on a wide range of substrates (such as corrugated boxes, paper, film, etc.). Compared with the aforementioned resin letterpress and offset printing plates, the mechanical strength of flexographic plates is slightly inferior. However, flexographic printing is a printing method that does not require ink adjustment and uses anilox rollers that provide a stable amount of ink to evenly coat a certain thickness of ink layer on the graphic part of the printing plate, and then transfers the ink layer of the graphic part to the surface of the substrate under the pressure of the impression roller to form a clear graphic.

In this process, the ability to set a stable "kiss-touch" printing pressure is a very critical factor in flexographic printing. Therefore, the accuracy and configuration of the printing press, the viscosity of the ink (pH for water-based inks), the reproducibility and thickness of the printing plate (plate makers), the elasticity of the tape, and the thickness management require a great deal of knowledge on the part of the printer in the daily production process. However, once the relevant characteristics are mastered, it is possible to print as smoothly as conventional resin letterpress and offset printing.

Except for some special plate characteristics, the chemical properties of flexo plates provided by each plate manufacturer are basically the same. In flexo printing, the corresponding types of presses, inks, etc. will vary depending on the type of printing for corrugated boxes, flexible packaging (film), labels, paper bags, etc. Although there are various types of plate thickness, hardness, etc., the characteristics are basically the same. Therefore, the printing plates sold by different plate manufacturers and the water-based inks, solvent inks, and UV inks sold by ink manufacturers are all of a common design.

It is worth noting that UV inks differ in formulation composition from one manufacturer to another, and testing is recommended before use. On the other hand, usually inks for resin letterpress, gravure, and offset printing are less resistant. If used directly, it causes the resin to swell causing a reduction in the physical properties of the printing plate.