Make corrugated paper more colorful printing (below)

Defoamers are used to eliminate the trouble caused by the foaming caused by agitation during the printing process and the ink production process. Foams are often difficult to eliminate. Excessive use of defoamers will prevent printing from proceeding properly. Some defoamers contain hydrocarbons that adversely affect flexographic printing plates.
Foam generation is related to the hardness of the water. Silicon-based defoamers need to be diluted with water, and they should be agitated at a constant rate when incorporated into the ink. An undiluted, concentrated silica-based defoamer can cause pinholes or white spots in printed matter. Therefore, defoamers must be used with caution. The amount used should not exceed 1% and should be used after dilution.
The change in the PH value of the pH water-based ink not only affects the ink transfer but also affects the printed color. If the pH is too high, the amino group on the surface is too high and the water-based ink drying speed will slow down. On the contrary, if the PH value is low, the viscosity of the water-based ink tends to fluctuate greatly, and the resin will precipitate in the ink.
The pH value of the water-based ink can be detected with a standard pH meter. The conventional water-based ink is alkaline, the PH value is about 7 or more, and the normal applicable range is 8-9. In addition, the PH values ​​required for different formulations of ink are also different.
In order to obtain good printing quality and meet the requirements of customers, attention should be paid to the entire process from the product design stage to the final product delivery to each household, understand the process requirements of each stage, and try to meet the production requirements, and consider the following factors:
The quality of the original;
Bar code specifications;
Guidelines for optimal number of halftones for multicolor halftones;
Ink type and quality The ink absorption and uniformity of the substrate;
Control element
Anilox roller parameters and scraper type;
Gray balance;
Ink viscosity and pH control;
Ink overprint
The pressure between the anilox roller and the plate roller;
Printing pressure
Loading
Loading system;
Plate type, thickness and quality.
Plates that have a good effect on printing quality can get better printing results. It can reduce the dot gain, make the printed image sharper and the ink transfer better. When printing corrugated board, the best printing effect can be obtained with the minimum pressure. To reduce the dot gain in the corrugated box printing with the post-printing process, the ink transferability in the solid area is good, and generally, 3.18mm or 3.94mm thick can be used. Photoresist flexo, plus PU foam liner. The liner under the plate is compressible and absorbs printing pressure. The printing plate and the foam gasket work together to reduce dot distortion and reduce dot gain. Different types of tape structure, hardness, elasticity, adhesive strength, ink receptivity and ink release, etc., there are differences, and have different effects on the printing quality, should be in accordance with the different image content and adapt to the image of the tape model Used for plate mounting.
The depth of the image after the etching of the printing plate is to be carried out according to different printing machines, printing materials, plates, and printed materials. The company uses a new type of flexographic printing machine to print high quality halftones or fines on coated paper or semi-coated paper. When the graphic is in line, the depth of the graphic highlight should be 1-1.2mm. When using ordinary printing machines to print solid or thick text, the depth of the graphic text should not be too shallow, and the protrusion depth should be 1.5-1.8mm. Corrugated box after printing process should choose thicker photosensitive resin plate thickness of 2.84-3.18mm. If a corrugated red box requires high-quality half-tone printing, with 80 lines/inch images and UPC barcodes, a thicker version should also be used.
Digital version can be used in corrugated box post-printing process. Digital technology-based flexo platemaking is the latest technology in flexo printing today. It enables flexo printing to achieve excellent print quality and achieves and surpasses offset and gravure quality in certain aspects. . Direct Platemaking Process In the process of plate making, oxygen can inhibit the reaction rate of the resin chemical reaction, and can achieve the best balance in the inhibition of oxygen and UVA curing, making the outlets more tax-efficient and effectively suppressing the increase of network points. The use of a hard, compressed gasket material results in excellent screen printing of network images. Compared to conventional flexographic platemaking techniques, the network point reduction can be reduced by 15%-25%.
With the emphasis on environmental protection, the pre-printing process of corrugated cartons has gradually moved from gravure and offset printing to flexo printing, and the digital version is used as the printing plate of the corrugated box pre-printing process, which can also make the flexographic prints colorful and clear.