Cosmetic Box With Clear PVC Offset Printing Image Color Control Technology

Cosmetic Box With Clear PVC offset printing image color control technology

The eternal theme of printing is the transmission and reproduction of color, how to make the currently commonly used offset printing image quality better in color reproduction through different color control technology, is the current challenge faced by domestic enterprises. Based on the summary of the most advanced offset printing image color control technology in the world, this paper puts forward a new point of view in view of the development trend and characteristics of China's printing industry, and points out the research direction of color control technology in the future.

It is generally believed that due to the printing principle of offset printing, it is an inevitably unstable printing method. The "oil" in the ink and the "water" in the ink tank do not always blend as well as one would expect, so for printing press manufacturers and consumer goods suppliers, the entire process must continue to be painstakingly controlled. For printers and print buyers, this means that a compromise can only be reached at the end of a very long verification process, that is, to achieve "commercially acceptable quality" rather than the print quality that can be foreseen in advance.

But that has changed. The current use of digital technologies in the printing and publishing world is key to their success. Digital technology makes color quality control and consistency control no longer a very technical matter. For example, CTP reduces the capricious uncertainty in the process of plate making. The plates that are exposed now can be sure to get exactly the same plate when they are remade 3 months later.

The current printing press already has good control performance. On the printing press, the auxiliary plate mounting device will reduce the problems caused by uneven padding, and the temperature-controlled roller eliminates some other uncertainties. At present, several common color control methods are as follows.

1 Color control method based on ICC file

The American Reader's Digest magazine, for example, is published in 48 editions and 19 languages in more than 60 countries around the world, including 20 editions in Europe. In addition to magazines, they also distribute other products including books, such as music, videos, and other specialty products. As their distribution and delivery methods have expanded, companies have correspondingly expanded their range of printed products, both electronic and traditional.

Image printing is a task for all print sites that print Reader's Digest, and it involves a lot of repetitive work and expense. Different printing locations make it almost impossible to control the image quality of different versions, and color management is especially a problem. Color quality and appearance differences can occur from tone inconsistencies to severe color deviations. To avoid similar problems, they adopted a set of Colour Systems. This is a website dedicated to managing all the European editions of Reader's Digest files. Including library files, product files, images and graphics. The company has now established a new workflow to ensure consistency across different media and printing houses. In different parts of Europe, operators can use special urls and passwords to access the site to ensure consistent printing.

Colour Systems processes RGB images input from a drum scanner. With each scan, a scan correction ICC file (also known as an ICC device connection file) is used to convert the color of the image into the CMYK color space of the SRD (selected Reader's Digest). When required, the scanner is regularly maintained and checked according to established control procedures and documents. This ensures that both the input original image and the final output image color and ink characteristics are up to standard, thus ensuring color reproduction and matching on the press.

2 Frequency modulation screening technology combined with chroma color control method

These changes have in turn aroused interest in FM and other technologies. Agfa's Sublima, for example, has studied the size of the minimum dot at which a printing press can be reliably replicated. If the dot size is 60μm, it can represent 6% of the dot number of 150lpi plus cable or 8% of the dot number of 250lpi plus cable. Under normal circumstances, this means that the printer is limited to a relatively low resolution. With Sublima, you don't have to try to print smaller than the smallest point of the press, but reduce the number of points in an area of less than 6% to achieve higher profile parts. The effect is immediate, the press can print more surprising network lines than expected, the high profile parts appear brighter and the middle tone is richer.

Creo is one step ahead in promoting the use of FM screening, but it does not only emphasize the impact of very small dots on print quality, it also promotes the application of balanced oil and water distribution due to the consistency of its dot size. This result is better, the printing press can be controlled more consistently, the amount of ink is reduced, and the printing process can be better controlled. This is critical for long-form web offset printing, which is why 40 percent of magazine printing in the United States uses FM screening.

As Polestar began using Creo's Stacatto FM screen in its web offset printing shop, FM screen was also used in magazine printing in the UK.

Between 1970 and 1980, registration control on web presses was a high technology, and now it is added color closed-loop adjustment capability, that is, adaptive capability. The closed-loop color control system from QTI and GMI, once set, ensures that the same color is maintained throughout the printing process. As the ultimate owner of QTI, QuadGraphics is trying to ensure that no human intervention is needed on the printing press. In contrast, GMI is a big step ahead in using chroma values to achieve quantitative printing.