How to realize water-based printing of corrugated paper with high mesh line

Most of the printed samples will see some water-based direct prints with high mesh lines (some up to 110 lines) or some offline pre-printed products. And several well-known domestic machinery and equipment manufacturers are also promoting such products. Water-based direct printing equipment factories such as Nanhai Dongfang, Shanghai Dinglong, Beijing Dobeck and Taiwan Changsheng, TCY, etc .; offline pre-printing machinery manufacturers such as Qingzhou's Egofa and Guangzhou Kesi Gao. It is unthinkable that the high-net-line prints they produced were made with domestic equipment a few years ago.

The water-based printing of corrugated paper with high mesh line is a comprehensive system coordination process. It does not depend on which link does the job well. It requires related links such as plate making, ink, corrugated paper and cardboard, printing equipment, printing technology, etc. Adjust and cooperate with each other to achieve a relatively optimal value, so that a beautiful product can be printed. The following is a brief discussion on how to realize the water-based printing of high-net-line corrugated paper.

· In terms of flexible plate making, determine the best solution that is suitable for both printing and product design

Determine printability conditions

First, we must understand the customer's printing equipment, such as the color number of the unit, the type and line number of the anilox roller, the basic conditions of the paper feeding system, and the scraper system. And the type of paper, is it white paper or coated paper or other. Conditional platemakers generally provide a set of test plates to test the printing suitability of the printing press. It includes a ladder bar for testing the expansion of different network lines and dots of the flexographic version, a color block used to measure the solid density value of the ink, a simple chromatogram with different dot ratios overprinted, yin and yang characters and straight lines of different font sizes, a module for measuring color error To observe the pressure bar of the printing equilibrium pressure and so on. The test printing plate needs to be completed under normal production conditions such as normal printing board, standard production of water-based ink, normal printing pressure and vehicle speed. Of course, you can change some printing conditions to get different test samples. Through the analysis of the test sample, we can get the printability of this type of printing machine under this condition. The dot expansion curve of each color, the solid density of the water-based ink, the hue value, the dot collision situation, the influence of the color sequence, the reduction of thin lines, the overprint error, and the printing balance pressure can be obtained.

Combining the test data obtained above and the printing effect of the test sample, the plate-making company can establish a color matching management system for this printer, such as establishing a dot compensation curve for dot expansion, screen color and gamma curve correction, and proofing machine Color simulation and matching, etc.

Determine the plate making process and color separation plan

In flexo platemaking, the determination of the color separation process is a critical factor. To a certain extent, it plays a decisive role in the success of printing high-wire products. The outstanding research and development in this respect is Yingjie plate-making company. The company has been devoted to the research and promotion of carton color water-based high network cable platemaking for many years. In 2004 and 2005, China Flexo Association and DuPont Corrugated Competition were the biggest winners, and won the "Outstanding Contribution Award" in the platemaking industry. The specific details of the two award-winning works of the company will be explained below.

The foreground of the "JVC" audio packaging box is a clear speaker, and the background is a kind of effect that gradually changes to a net, which is a little hazy. This effect of gradual transition to absolute screen is easier to achieve for offset printing, but it is more difficult for watermarks to follow the conventional halftone method. Discrete frequency modulation dots will destroy the details of the image, but for corrugated boxes such as large areas with pitted surface printing, it is not easy to appear ribs. In addition, it will be more natural for the screen, and there will be no hard holes. Therefore, the company decided to use the usual dot network for the foreground sound, while the background uses a discrete FM network, and adjusts the range and sequence of each color in accordance with the color of the product. The watermark effect obtained in this way, on the one hand, because the foreground and background use different mesh types, the foreground effect is more prominent, the background gradient is natural and reasonable, highlighting the sense of haze, and well reflects the designer's design ideas. On the other hand, the discrete outlets adopt a certain screening technology, which increases the anti-counterfeiting of products. So the customer was very satisfied, the signing was successful once, and all series of "JVC" were transferred to the watermark.