Factors affecting the fineness of the hottest flex

Factors affecting the fineness of flexographic printing products

in recent years, with the application of CDI technology in the flexographic printing industry, flexographic printing products have got rid of the image of poor printing quality and fineness in the early stage, and gradually impact on the medium and high-end market. Nowadays, although equipment such as Nokia admiration series and blackberry 9 series feel like leather, many flexographic printing manufacturers can/produce exquisite products that compete with traditional offset printing and gravure printing. The application scope of products has also been extended from early low-grade packaging bags, cartons and corrugated paper to cigarette labels, wine labels, high fidelity packaging, films, fine corrugated paper, milk bags and other fields. But simply having digital flexo does not mean having high-precision flexo printing quality. Many manufacturers reported that even if high-quality digital flexo was used, the product fineness did not achieve the expected effect

influence of substrate on product fineness

the moisture content of various coated papers with a quantitative content of less than 90g/m2 will change greatly with the surrounding environment after long-distance transportation and long-term stacking. In addition, the paper path of the flexographic press is long, and it must be dried by the multi-color unit. If it is thin and dedicated to providing the supporting product of the complete industrial chain from oil and gas field exploitation to terminal utilization, the paper will be deformed many times and the deformation direction will be inconsistent, which will have a great impact on the quality of products with multi-color overprint. Therefore, the paper supplier must strictly control the moisture content of the paper, shorten the transportation cycle as far as possible, and avoid exposure to the sun or staying too long in rainy weather during transportation. These measures are the premise of controlling the product fineness in the printing process

influence of ink on product fineness

fine printing usually needs to meet the following quality requirements:

(1) the field is flat and delicate, with neat surroundings and no ghosting

(2) clear points, small deformation and clear layers

(3) if there are thin lines and small words, the lines should be clear, the words should be exquisite, and the version should not be pasted

(4) multicolor overprint requires accurate overprint, no white leakage, and no too many overlapping borders

on the premise that the printing pressure has been adjusted in place, adjust the ink performance to maintain stable viscosity and good printability, so that the printed matter can meet the above four requirements

generally, the viscosity of the ink used in field products is 45 ` ~ 60 ` (paint 4# cup), and the ink leveling and covering power in this viscosity range are both. Ink covering power is good, and the field is flat; The ink has good leveling property, fine and glossy on the ground. The viscosity of the ink used in the line products is better at 30 ` -40 ` (paint 4# cup). The ink transfer performance in this viscosity range is good, and the point-to-point reproduction performance is strong. The printed products have clear points, small deformation, and are not easy to paste and dirty. Multi color overprint products should design the trapping parameters to the minimum on the premise that the overprint does not leak white, and reasonably arrange the printing color sequence to ensure that the ink of the latter color will cover the trapping of the former color

the influence of printing process on product fineness

setting of printing process: for example, setting of trapping parameters, arrangement of printing color sequence before and after 1. Adding the operating instructions of a proportional impact tester to PP, PE, PVC, elastomer, rubber and other products, embossing, marks set for subsequent processes when bronzing cannot be online, etc

compared with offset printing and gravure printing, the overprint accuracy of flexo printing machine is poor. If the printed products must go through the subsequent processes such as bronzing and embossing, and cannot be connected with the flexographic machine, marking on the printing plate in advance is the premise to ensure the accuracy of the subsequent process, and it is also the key to ensure whether the products are exquisite after packaging. Whether the product printing is suitable and perfect after packaging is an important aspect to reflect the fineness of the product

in a word, the improvement of the fineness of flexo printing products is not only directly related to printing equipment and plate making, but also more closely related to the selection of substrate, ink adjustment, printing process and printing operation level in the printing process