Water-based printing of corrugated paper with high mesh line (2)

Plate selection of high net cable plate making

The printing plate used for high screen printing has a hardness slightly higher than that of the general printing requirements. This is because this printing process requires a small amount of ink in order to accurately reflect the fine dots. If the printing plate is too soft, the ink transfer volume will be too large, which is not conducive to the control of the ink volume, and it is easy to appear faults such as color shift and network blocking. In addition, it also requires the plate to have a good dot reproduction range, which can produce small high-gloss dots; it has a uniform thickness and good flatness, which is convenient for light pressure printing and easy reproduction of the original; it has good flexibility , After being pressed, it can restore the original thickness and the plate must have a certain toughness, and the small dots are not easy to wear. At present, the plate materials commonly used for this type of printing include DuPont's TDR.

The requirements of high net line water-based printing on paper, cardboard and water-based ink

cardboard

To achieve an effect comparable to offset printing, it is best to use coated whiteboard. Because the coated white paper has a better finish, the imprint is more shiny and bright. Ordinary whiteboard paper has poor surface gloss and dull, dull color. In addition, coated whiteboard paper is different from offset paper and coated paper. It retains some of the original characteristics of whiteboard paper-permeability and adhesion, which is conducive to the printing of water-based inks. Cardboard can be used with uniform thickness, smooth paper surface, moisture control at 9 ± 2% and good hardness. Corrugated E-type, F-type or G-type corrugated paper with a weight of about 180g / m2. This kind of cardboard has low corrugation and flat cardboard, which can withstand more pressure, reduce ribs and false marks, and improve print quality. Currently coated whiteboard paper can be provided by the Finnish paper company, there are several domestic manufacturers in Guangdong can also provide.

Ink

Ink is a key factor in the entire printing process. For four-color overprinted high-net-line jobs, we must pay attention to the choice of ink. The ink of printed coated paper is different from ordinary ink, it mainly requires the following characteristics:

Good fineness-clear dots, delicate patterns; high gloss-bright and bright colors; low viscosity-no blocking nets, ink bars, clean and refreshing graphics; high color content-full color, rich connotation; attachment Good-anti-wear, no fading; good leveling-uniform color, no exposed bottom; fast drying-good color stacking effect, no dragging; good overprinting-good compatibility between colors, natural color, harmony, level rich. At present, ink manufacturers that can be widely used for printing on coated paper are Guangdong Mingfeng Ink, Yingjie Ink, and Oriental Ink.

Requirements of high net line water-based printing on equipment and printing operations

Equipment requirements

scraper

The printing machine that can complete the high screen printing must have a scraper, and also requires a sealed double scraper, and maintain the effectiveness of the scraper scraping, in order to accurately control the ink transfer.

drying

Drying device is a more important configuration of new printing equipment. Because the ink drying on the coated paper by penetration is significantly slower than ordinary whiteboard paper, multi-color nesting requires the first color ink to dry as soon as possible, and the latter color can be stacked smoothly, so advanced printing machines either use cold air drying or increase the unit Distance to allow the board to have enough time to dry, or equipped with infrared, UV and other drying devices.

Closed circulation ink path

Closing the ink path helps prevent excessive contact between the ink and the air, and prevents certain components of the ink from volatilizing, oxidizing, and dissolving into air bubbles. Only by maintaining the stability of the ink composition can high-quality printing be successfully completed.

High net line anilox roller

This is one of the most important conditions for achieving high screen printing. The higher the number of screen lines, the higher the screen lines that can be printed, and the smaller the amount of ink transfer, which helps to reproduce small high-gloss dots.

Suction paper feeding and full paper feeding can improve the flatness of the cardboard and smoothly feed the paper to ensure accuracy and register accuracy.

Liner (between printing plate and plate roller)

Better pads can cushion and adjust the pressure, protect the fine dots, and increase the life of the printing plate.