The application of electronic paper and electronic ink

The concept of "electronic paper" can be said to have been proposed by Xerox Corporation in the early 70s of the last century. The intention was to refer to alternatives to computer monitors; the concept of "electronic paper" will continue to evolve and it will appear to be rolled up like a newspaper. You can write "electronic paper" repeatedly. Philips, based in Eindhoven, the Netherlands, is developing an "electronic paper" consisting of a 1mm-thick "paper" containing "electronic ink", that is, millions of black-and-white pigments. The microcapsules, which can only be seen under a microscope, are black at one end and white at one end. When the "paper" is energized, these microcapsules rotate under the effect of current, with one end facing the "paper" surface. According to the display needs to be controlled, the black and white ends of the ball can be rotated in the specified direction. Facing the surface of the paper, if it is black, it represents a dark image; if it is white, it represents a bright image; in this way, the image or text can be formed. According to Philips’ technologists, the first products will be launched in the first half of 2003.

An American company, E Ink Corp., developed an "electronic ink" product called Ink-In-Motion, which can be used to generate point-of-purchase (point-of-purchase, point-of-purchase) advertisements for the first time at the Salt Lake City Winter Olympics. Debut for "Coca-Cola" vending machines and dynamic display signs around the Olympic Square. A set of such design and display devices worth 500 US dollars, including light and animation display materials. Ink-In-Motion's imaging on POP shows that it is not a still image that can flash changing text and images. The display media is a cardboard sheet no thicker than x-pt. It is driven by 2 AA batteries for 1 year.

E Ink electronic ink is a patented product. It is not an ink but a microcapsule suspended in a transparent liquid and composed of positively charged white particles and negatively charged black particles. When a negative charge is applied, the white particles move to the display surface of the microfilm to form a bright-toned image; when a positive charge is applied, the black particles are pulled to the display surface, resulting in a darkened image. The "ink" is printed on a plastic film that is laminated to a thin layer of electronic system that is controlled by the display driver to produce the desired pixel pattern. The micro-membrane is suspended in liquid and can be printed on most plastic, glass, fiber and paper surfaces.


The concept of electronic ink can be traced back to the 1970s. Nick Sheridon, a researcher at Xerox at the time, proposed this concept. But the real development of electronic ink is the Bell Labs of the Massachusetts Institute of Technology (MIT). Since then, Xerox has been catching up and now both of these technologies are among the best in the world. Although some companies are also researching electronic ink, MIT and Xerox are still respected in terms of mature technologies and products.

1. The principle of electronic ink

Electronic ink uses the principle that the positive and negative electrodes of electricity attract each other. Although the principles are the same, there are some differences in the electronic inks studied by MIT and Xerox. The electronic ink developed by MIT utilizes the principle of electrophoretic movement. The ink is actually a tiny silicone capsule filled with negatively charged black particles and positively charged white particles in each microcapsule. With the change of the current, the motion is carried with black and white particles of positive and negative polarity, respectively, to form a graphic. Xerox uses a small bead with a diameter less than 100 microns. These small beads consist of two hemispheres of different colors, each of which is positively or negatively charged. Small beads are placed in tiny holes in the film. The holes are covered with a transparent liquid that allows the beads to rotate freely. Whenever the current passes through the e-paper, the electric field acts to turn the glue ball and control the text or image of the part.

At present, there are many companies that develop electronic ink, but the most familiar ones are E-Ink and Gyricon Media. E-Ink was established by the staff of MIT's Bell Labs and produced electronic ink based on the results of MIT's research. Gyricon was split from the PARC Institute in Xerox. Both companies are committed to the use of electronic ink in the commercial context.

2. Application of electronic ink in printing

Nowadays, a new type of electronic ink suitable for digital printers is also mentioned in the press. It contains charged liquid ink droplets, making it possible to electronically control the placement of ink droplets in digital printing. Electronic inks can reach very small particles (1 to 2 microns), giving the print higher resolution and smoothness, sharpened image edges, and extremely thin image layers. Electronic inks have now played a role in the following areas: the basic color CMYK (cyan, magenta, yellow, black); wide color gamut six-color settings, increase the orange, purple, so that the color reproduction capability is much higher than the original four-color basis Color reproduction capability; Indigo spot color system compatible with PANTONE; opaque white coating of colorless printing materials; fluorescent ink. Compared with traditional inks, electronic inks generally have the following advantages:
(1) High brightness, high definition and durability.
(2) Strong printability, suitable for almost all material printing.
Today's digital printing technology, with electronic ink, shows many advantages, mainly reflected in the following aspects.
(1) Edge sharpness and sharpness are good. It can be clearly seen from the high-magnification results that the image formed by the electronic ink is clearer and sharper than the image formed by the electro-photographic dry powder, and this advantage is more obvious in continuous-tone images. In addition, since the electronic ink particles are minute and are printed by a transfer method, the background of the formed image is clean and free of pollution.
(2) The dot gain is small and the color consistency is high. Take the Indigo digital color printer as an example, it has a correction function that can control the dot gain and also automatically adjust the density so that each print has the same appearance.
(3) High image smoothness. Electrostatic dry powder printers or copiers can only output images with the same smoothness regardless of the material of the paper. Digital printing machines that use electronic inks match the smoothness of the electronic ink image with the substrate and, like a conventional offset press, can produce effects ranging from rough to dull to high brightness. The actual operation shows that the ideal smoothness of the electronic ink can basically meet the requirements of various papers other than super-glossy paper.
(4) Large color reproduction range. Electronic inks can be printed according to international color standards. All of these standards are based on CMYK. Offset printing requires the use of different ink formulations based on different standards, while electronic ink uses only one set of colors for different standards. The special properties of the electronic ink and the charging characteristics of its ink determine its unique function on the basis of CMYK four colors. In addition to the four-color basic color, the spot color electronic ink can also print a color range that cannot be achieved by the four-color basic color.
(5) Fast drying. The electronic ink can be cured when the finished product leaves the press without further drying. The relatively low drying temperature (100°C) of the electronic ink does not cause the substrate to be damaged or curled.
(6) Prints do not fade under light.

The application and development prospect of electronic paper and electronic ink

At present, the performance of electronic paper and electronic ink is still being matured and perfected, and the application field still needs to be expanded. The current development of electronic paper and electronic ink applications mainly in the following areas.

(1) Display

The appearance of this display is just like printed matter. Compared with general electronic displays, it has many advantages such as low energy consumption and light weight. In addition, it can also be used on televisions. According to reports, the UK's Cambridge Display Technology (CDT) laboratory has created a light-emitting plastic compound that can be used to make thin, curlable televisions. It can be speculated that the future television will be "printed".

(2) Radio receiver

The transistor is printed on electronic paper and a radio receiver is integrated. Newspapers printed using this kind of electronic paper can use the lights in the room as energy sources, receive radio signals such as various news and information, and update the contents at any time and anywhere. The news is truly new and the information is often rich. Everyone needs to check and update the required content at any time. Therefore, it can be said that this will be a newspaper that will never be out of date. (3) Universal Book The universal book consisting of electronic paper is covered with "microencapsulated" particles on each page, and the electrodes can be installed in the book. No matter what the appearance or feel, it is just like ordinary books. The difference is that after reading, people can download new content from the e-book to the page, and they can even do so during the reading process. According to reports, the MIT Media Lab and California's Xerox Company are both developing their own versions of the electronic paper "magic wand." Its shape is like a pencil with internal memory chip and electronic contactor. When the "wand" slides on the surface of the electronic paper, its memory chip converts the acquired information into pixels. If connected to a computer, it becomes a tool for rapid transmission of information. Experts estimate that the memory chips will be smaller and smaller, and the storage of information will be even greater. One day, an e-book will be able to store the contents of 35,000 ordinary books. In addition, overseas research and development of e-schoolbags are also being carried out so as to greatly reduce the weight of students’ schoolbags. As long as they have a lightweight e-schoolbag, they can include all textbooks, extra-curricular exercises and teaching reference books for learning, and they can do illustrations. Lively and lively.
(4) Writing Using the "electric pen," you can write on electronic paper. Perhaps one day, you will use it in teaching.
(5) Used in printing To improve the structure of the printing press and add electronic ink, everyone can use a large number of electronic paper prints.
(6) Electronic wallpaper This type of wallpaper can be selected and changed at any time based on people's preferences, seasons, time, temperature, and activity content, making the wallpaper look new.

In addition, according to expert analysis, the market for e-paper and electronic ink should mainly be e-book readers. There are many articles about e-books and physical books. Everyone agrees that there is still a certain distance between e-book readers' reading comfort and traditional books and periodicals. This limits the degree to which e-books are accepted. Of course, the development of e-books is also affected by many factors such as the development of computer networks and the format of electronic books. However, when the technology of e-paper and electronic ink is mature, e-books and physical books will be closer and easier for people to accept.

Today's e-paper and electronic ink research efforts are mimicking real paper and ink. At present, it is very similar to real paper and ink except that it cannot be compared with real paper and ink. When the technical problem of electronic ink printing on ordinary paper is solved, the difference between electronic paper and plain paper will be minimal.

So, in a world without paper and ink, do you still need to print? As long as the application range of electronic paper and electronic ink is analyzed, it can be easily judged that electronic paper and electronic ink cannot fully replace real paper and ink. Because the scope of printing is too big. In addition to the printing of books and advertisements, there is packaging printing, and packaging printing can almost be said to be an area where electronic paper and electronic ink can never enter. For packaging paper, variability is not what it needs, and in reality, many packages are disposable and are not necessarily recycled. So for the time being, there is no possibility that electronic paper and electronic ink will enter the packaging market. Since there is still a large market for package printing, the demand for paper and ink is still large.

In the publishing field, before the application of electronic paper and electronic ink