First, the development of ink
In the printing industry, the status of ink is self-evident. The presentation of text and images relies entirely on the use of ink and printing materials. Colorful packaging, eye-catching outdoor advertising, colorful books, these are inseparable from the credit of ink. Different kinds of printing processes have different requirements on the nature of the ink, which makes the type of ink continuously refined. At the same time, with the development of the printing industry, ink has not only been used to present graphics, it also has anti-counterfeiting, decoration and other effects. A variety of inks with special processes continue to emerge, making the ink family more and more large, and its members also have their own characteristics. In recent years, there has been a type of electronic ink that has been quietly appearing in the ink industry, and has attracted people's attention with its unique personality and will have a certain impact on the way humans obtain visual information.
Second, the technical advantages of electronic ink
1. The emergence of the cause network once brought a big impact on traditional books and newspapers. On the Internet, we can read news, read novels, and browse a variety of information, and can be based on personal preferences. With a selective look, the degree of convenience is self-evident. Some people once worried that our traditional paper-based newspapers and newspapers will be replaced by the Internet. However, it turns out that people's reading habits tend to be the traditional way of reading, so the paper and the presentation tools of these images and texts—inks It cannot be abandoned. But now, people's requirements for books are also getting more and more exquisite. This increases the weight of the books to some extent. Therefore, books are no longer simply a tool for leisure, but have become a burden to a certain extent. How can we make traditional books lighter, easier to carry, and increase the amount of information? We need to reconstruct the paper, and electronic ink is the tool for presenting graphics on this new material.
2. Structured electronic ink is produced by E-ink Corporation of the United States, which has the appearance of traditional paper ink and the ability of electronic display. The structure is shown in Figure 1. It is itself a liquid consisting of millions of microcapsules with a diameter of about 100 μm (similar to the thickness of the hair), and the capsule consists of white particles suspended on colored dyes. White particles are key substances and are small particles of titanium oxide. The microparticle capsule is sandwiched between two electric fields of opposite polarity. When titanium oxide itself is negatively charged and the electric field applied to it is positive, it will move to a positively charged surface. Then it can display white pixels; if the polarity is reversed, the negatively charged titanium oxide particles are repelled away from the top layer, the dyed ink is revealed, and these different colored capsules are appropriately arranged and assembled. A variety of characters and patterns can be printed, and grayscale images can be obtained by controlling the position of the titanium oxide particles in the capsule. As long as this electronic paper is not damaged, it can be reused numerous times.
3. Advantages Compared to traditional inks, some advantages of electronic inks are outstanding:
1 High printability, suitable for almost all materials. Regardless of its obvious personality, electronic ink is always an ink, and it must have basic ink compatibility—printability. It can be printed on textiles, paper, plastics and many other materials. Unlike liquid crystal displays, electronic inks can be displayed on plastic surfaces, making them slim, flexible, and non-breakable.
2 The sharpness of the edge is high and the image is clear. Compared with the image formed by the electronic ink and the image formed by the electrophotographic dry powder using a device with higher precision, the former has a sharper degree of sharpness, and this advantage is more prominent in the continuous adjustment of the image during printing.
3 good lightfastness, not easy to fade. Unlike traditional inks, pigment particles in electronic inks are encapsulated in plastic resins that protect the pigment's chemical composition from oxidation or humid air, and do not change under ultraviolet light.
4 Dry quickly. For traditional inks, the ink will have a dry process after reaching the substrate. For different inks, the drying performance is also different, and the required time is not fixed. It is appropriate for different printing processes. Further drying is performed, but this is not required for electronic ink. Once the electronic ink is transferred to the substrate, it will be automatically cured, so it can be said to be instantaneously dry. In addition to the above advantages, it also has some unique features:
1 High brightness. The display brightness of the electronic ink is 6 times that of the LCD liquid crystal display and its display media material thickness is also about 30% thinner than the LCD liquid crystal display. Reading from any angle does not produce a change in brightness, with a 180-degree viewing angle. There is no strict requirement on the strength of light, and the reading effect of light of different strengths and weaknesses will not change.
2 Electronic ink has low energy consumption, long-lasting effect, and stable image quality. After the paint particles in the ink reach a state, the graphic is formed. After the power is turned off, the graphic composed of the electronic ink can remain on the screen, so that after the page is formed, the power supply can be read without additional power. Energy support. Only consume energy when the content changes. To change a 3 inch character takes about 12mj.
3 This type of electronic ink can be used in a large area due to its low cost and can be constantly brushed and new. At present, the design of the symbol display of the electronic ink adopts a refresh frequency of less than 1 second, and the refresh rate that may be achieved exceeds 60 times per second.
4 wide color range. Similar to the color rendering ability of traditional inks, there are many colors. The electronic ink of its spot color system expands the color gamut to a color gamut that cannot be achieved by the four-color basic color. Printing according to international color standards, electronically adjusting the color concentration to suit different printing needs. The color electronic ink display tool can display thousands of colors.
Third, the application of electronic ink
At present, due to the fact that electronic ink has gradually become familiar to people, its application range is also increasing day by day. For example, it can be used for web printing, as an opaque white coating for colorless substrates, it can also be used for glossy advertising papers and other large format labels, and its inherent characteristics allow it to be displayed flexibly, just like on paper. The display is the same as shown in Figure 2. The electronic ink can also be printed on a curved surface, the surface of the printed product can also be curved; and power consumption is only required when the content needs to be changed. Indigo spot color systems compatible with PAN-TONE also have electronic ink applications. In Indigo's color digital offset printer, there is a unique combination of features, the printer uses electronic ink (ie, Indigo's unique liquid ink). The electronic ink can reach very small particles (1 to 2 μm), so that the small particles enable the printing to reach higher resolution and smoothness, sharpen the edge of the image, and form a very thin image layer.
Sony Corp., together with EInk in Massachusetts, Philips in the Netherlands, and Toppan Printing Technology in Japan, introduced the Ebook reader Librie, which also uses E-Ink electronic ink technology. The reader has a resolution of 800600 dpi, and the clarity of black and white fonts is enough to outperform any LCD screen.
At EXPO 2005 in Aichi, Japan, ToppanPrinting demonstrated its mature E-ink electronic ink technology, a wall-sized E-ink display, as shown in Figure 3. This display consists of 272 individual electronic ink panels. ToppanPrinting's E-ink electronic ink technology is similar to the Sony LIBRIe e-reader. The latter has been convinced by many people with its delicate and flat display.
So far, the latest application of electronic ink is the world's first electronic paper watch, as shown in Figure 4. It was jointly launched by several companies such as E-ink Corporation and Japan Epson Corporation. This watch is easy to read, slim and bendable. Since its display does not require a backlight, its inherent stability memory capability does not require energy to maintain the image, so it also features low power consumption. This watch is expected to be on the market in 2006.
Fourth, the market outlook
1. Market potential. The application prospect of electronic ink is full of hopes and attracts many merchants. Hearst has invested millions of dollars in researching and developing reusable newspapers. Motorola also hopes to use it as an outreach product for wireless technology business. When Israel's Indigo introduced the world’s first digital color offset press E-print1000, it also used a new type of liquid toner called electronic ink. Its founding company, E-Ink, is also cooperating with companies such as IBM and Lucent Tech-nologies to produce electronic ink displays.
2. Prospects. At present, domestic manufacturers are still unable to produce electronic inks. In the field of digital printing, this is undoubtedly a blank for us to enable our printing quality to reach international standards as soon as possible, the research and development of new technologies, and the production of new products. Promotion is the direction in which we should focus our efforts. Due to the limitations of its price, equipment, and other objective conditions, the use of electronic ink in the country in a short period of time will not be as popular as traditional ink, but this does not obliterate its advantages. For the vast majority of printing plants, this is still an unknown area, its great market potential can not be ignored. We are pursuing high-quality printing products, and electronic inks have the ability to reflect the high quality of printing products. We believe that in the near future, the application of electronic ink will certainly become more extensive. Domestic printing manufacturers should also seize opportunities and compete in the future. There is an opportunity to take the lead.
Author: School of Information Engineering, Jiangnan University, Wuxi
Reprinted from: Guangdong Printing