Main problems encountered in label flexo

Update:06 Mar 2020

Flexo printing is the mainstream of China's label indus […]

Flexo printing is the mainstream of China's label industry. Although flexo printing is not as good as embossing in terms of total printing volume or offset printing and gravure printing on fine dots, the advantages of the stability, quality, and productivity of flexographic control of color difference are widely used in the market for high-end label products. Shares, which have become the mainstream of the label industry, do not have to be self-defeating.
However, there are very few label printing companies in China that can solve the defects of flexo blocking. In the printing of high-gloss small dots, the gradient screen of 150 to 175 lines / inch printing plate is attenuated to zero, which is the mastery of the absolute screen technology. The industry is far from universal. Therefore, in most of the flexo labels, the blank part of the screen where the net should be used is often replaced by a small dot bottoming process, which causes the highlights to be dark and the layers to be stuffy.
Because the ink on the printing plate cannot be completely transferred, it is easy to remain on the printing plate. When the residual amount reaches a certain level, it will be transferred to the printing material irregularly. The matching relationship between this ink and the printing plate has not yet been clearly established. At present, it is still at the experimental level, which has affected the advantages of high productivity and low consumption of flexo printing.
Label flexo printing uses a large number of UV inks, but the curing problem of UV inks restricts the high-speed production of flexo printing. Compared with the flexo ink production line and the production speed of 600m / min for the Tetra Pak production line, the curing problem of label flexo UV ink should attract the attention of the industry.
Currently, a large number of flexo label printers use gear transmission. The classic configuration is 1 / 8CP, that is, 3.175mm gear. The gear bar caused by the mismatch between the transmission gear pitch circle and the outer circle of the plate roller has always troubled the front-line operators, and the label waste rate caused by the ink bar is also an important aspect of flexo loss that cannot be ignored.