Basic principles, types and application scope of t

2022-08-22
  • Detail

With the rapid development of science and technology such as computer and electronics, mankind has entered the information and electronic age. Nowadays, technologies such as electronics, computers and networks have made rapid changes in the printing field from prepress system, printing, post press processing and other production links. In terms of technology and equipment, computer typesetting, graphic computer production, online publishing and printing, digital printing, e-books and e-newspapers are constantly emerging and developing. In terms of materials, the research and development of e-paper and e-ink have begun to move towards the market. What it brings to people is paper and ink completely different from the tradition. The application of e-ink adds wings to digital printing. The significant role of electronic technology in printing shows that the rapid development of science and technology will bring us unexpected results. But in these materials, electronic ink and electronic ink often give people some confused concepts, and some articles often call electronic ink electronic ink, in fact, the two are different things

electronic ink and electronic paper are interdependent things. They seem to be two things, but in fact they are one thing, so they are always mentioned in the same breath in narration. In short, electronic paper is a thin film, and a layer of charged material coated on the film is electronic ink. On the contrary, electronic ink needs a carrier. This piece of paper used to contain electronic ink is electronic paper. It can also be regarded as a thin embedded remote control display panel. Therefore, the concepts of electronic paper and electronic ink are different from those of traditional printing. Among electronic paper and electronic ink, only with electronic ink can there be the so-called electronic paper. The concept of electronic ink can be traced back to the 1970s, when Nick sheridon, who was also a researcher at Palo Alto Research Centre (PARC) of Xerox, put forward this concept. However, it was Bell Laboratories of Massachusetts Institute of Technology (MIT) that really carried forward the electronic ink. After that, Xerox rushed to catch up, and now both research are in the forefront of the world. Although other companies are also studying electronic ink, MIT and Xerox should still be respected in terms of technology maturity and product achievements

The basic principle of electronic ink is derived from the principle that the positive and negative poles of electricity attract each other. Although the principle is the same, there are some differences between the electronic ink cooled by MIT and Xerox. The electronic ink developed by MIT uses the principle of electrophoretic motion. This ink is actually some tiny silicone capsules. In each microcapsule, it is filled with transparent liquid, black particles with negative electricity, and white particles with positive electricity. Then use the change of current to move black-and-white particles with positive and negative poles respectively to form pictures and texts. The electronic ink produced by e-ink company, which was established by the staff of MIT Bell laboratory, is actually some very small resin capsules, which are transparent. There are carbon (black particles) with negative electrode and titanium oxide (white particles) with positive electrode in the capsule. The capsule is coated with film, which is called the front plate, and another layer of electrode is set under the capsule. If the current is passed through the electrode, carbon and titanium oxide will move up and down due to the principle of electrophoresis, and then form pictures and texts. These pictures and texts composed of black carbon and white titanium oxide look very similar to the printed text. Moreover, electronic paper does not have the error of viewing angle like ordinary monitors. Patterns and words can be read at different angles

Xerox does not use charged particles suspended in liquid, but small rubber beads with a diameter of less than 100 microns. These small rubber beads are composed of two hemispheres with different colors, each of which is positively or negatively charged. The small glue beads are put into the tiny holes in the film, and the holes are filled with transparent liquid, so that the glue beads can rotate freely. Whenever the current passes through the electronic paper, the electric field makes the rubber bead rotate, controlling what words or images appear in this part

at present, electronic paper and electronic ink generally have the following types

1 Microcapsule electrophoresis

this is a technology researched and developed by Massachusetts Institute of technology and E - ink company. The basic principle is to put dark dye liquid such as blue and light charged particles into the cell size transparent microcapsule, and connect the microcapsule to the film with transparent electrode with adhesive

adjust the electric field to electrophoresis the light colored particles to display the image formed by white and cyan. Titanium oxide particles are used in white particles, which are charged and stably dispersed in blue insulating liquid. The microcapsule was coated on the film with ITO electrode with silicone resin as adhesive. When the negative charge pattern is applied to the surface in the form of ion flow, the white particles move to the lower part of the microcapsule, so a blue image is drawn from the surface. Then, when the positive charge is fully applied, the white particles move to the upper part of the microcapsule, so the surface becomes white, and the image is eliminated. A color image can be formed by replacing a single tone charged particle with a material of different colors. The full thickness can reach 0 2 mm. The main problem of this method is that the response speed is only about 100 milliseconds, so it can not be well adapted to the continuous broadcasting of video images

2. Rotating ball (rotating ball)

Xerox company and 3M company jointly researched and developed electronic paper in the way of rotating ball (rotating ball), which makes the yield point difficult to identify

the basic principle is to produce a kind of spherical particles with white and black hemispheres, paint each half of the ball into white and black spherical particles, use silicone resin as adhesive to coat the two-color particles on the film with electrode and other supports, and fill the surrounding of the particles with specific liquid to form holes. The direction is controlled by the electric field, and the image is displayed in white and black. When filled with a specific liquid, the white side of the particle surface is negative; The black side is positive; Different charges appear between the two colors to form a dipole. If a negative charge pattern is applied to the surface of the cardboard, the particles will rotate so that the black hemisphere faces upward. If a positive charge is applied to the surface of the cardboard, the white hemisphere faces upward. In this way, the rotation direction can be controlled by the change of the electric field to form a black-and-white image or text. But its disadvantage is that it cannot be colored

3. Bichromatic dye liquid crystal

this technology is mainly developed by big Japan printing company and Tokai University. The basic principle is that the recording butterfly liquid crystal molecule a is mixed with two-color dyes to form peritectic shape. Under the action of applied voltage, the arrangement of liquid crystal molecules changes, and at the same time, the absorption of pigments changes. The specific composition is that on the ITO transparent electrode, the mixture of liquid crystal, bichromatic dye and resin is coated on the support with a thickness of about 6 microns. At the beginning, the pigment forms an irregular direction and is gray, but with the ion flow recording and writing image, the dye will be oriented to generate the recording of white image. Then, when the medium is heated to more than 60 ℃, it will return to the original gray state, so that the image can be eliminated. If it is contrary to this method, it can be made into a white state first according to the corona discharge, and the thermal head can also be used for thermal writing to form an image

4. Liquid crystal organic photosensitive composite film

the basic principle of liquid crystal organic photosensitive composite film is that when there is no electric field, cholesteric liquid crystal is parallel oriented, which adapts to the helical spacing of liquid crystal to selectively reflect light. When the electric field is weak, it becomes the focal cone orientation and transmits light to maintain its state. If the electric field is further strengthened, it will return to the parallel orientation. Therefore, display and non display can be controlled through the change of electric field. To write to the media, just fit the organic photoconductive film. In practice, organic photoconductive films need to be laminated to control the partial pressure of the liquid layer. In this way, 600dpi patterns or 8-point text can be displayed, and A6 specification on-demand media can be further made. It is reported that as long as RGB is overlapped in three layers, it can be used to display color patterns

5. The method of toner display panel

also belongs to electrophoretic display. Its basic principle is: fill the adhesive layer of black powder and white particles between the two glass plates with ITO transparent electrodes. After applying voltage, the black powder moves between the electrodes, displaying black and white patterns. The commonly used black powder is conductive toner such as carbon black, which will directly affect the working effectiveness of the machine. The white particles are carbon fluoride particles that are easy to slide. The ITO electrode is coated with a charge transport layer, which plays the role of injecting positive charge from the electrode into the toner. The black powder contacting the lower electrode is charged due to the charge injection from the charge transport layer, and moves towards the upper electrode according to the Coulomb attraction with the negative charge of the upper electrode

basic principle, type and application scope of electronic ink

2007/3/23/10:38 source: China packaging daily

there are 0 comments from friends entering the forum

at this time, it is drilling around in the white particle layer; The black powder reaching the upper electrode uses the charge transport layer as an insulating layer and is bonded with the help of Coulomb force. At this time, from above, it is black. Then change the polarity of the applied voltage. Then the black powder will move towards the lower electrode, and most of the charge transfer attached to the lower electrode has been realized in advance or close to the realization layer, when viewed from above; We see white particles, so they are white. Change the polarity of the applied voltage in this way; It can display black or white. At present, electronic paper mainly displays monochrome graphics and texts, and color electronic paper is still in the stage of in-depth research

at present, the performance of electronic paper and electronic ink is still maturing and improving, and their development and utilization are also in the initial stage. The application fields need to be continuously explored and developed

in terms of the application range of electronic paper and electronic quantity developed at present, there are mainly the following aspects

1 Display

this kind of display looks like a printed matter. Compared with general electronic displays, it has many advantages, such as less energy consumption, light weight and so on. When the power is turned off, it still retains the image. In addition, it can also be used in TV sets. It is reported that the display technology (CDT) laboratory in Cambridge, UK, has been improved to produce a luminous plastic compound. Using this material, TV sets that are as thin as paper and can be curled can be made. This compound material can be printed on very thin plastic. It can be speculated that TV sets in the future will be "printed". Because this material can be curled, this kind of TV can be rolled up and stored like the projector screen when not in use. Experts predict that people will see this high-tech TV set on the market in the next five years. In addition, the material can also be used in various portable display devices, such as watch type TVs and displays

2. Radio receiver

because electronic paper only needs a small amount of energy to control electronic ink particles, a solar cell is enough. If more transistors are printed on this paper, a radio receiver can be integrated. The newspaper printed with this kind of electronic paper can use the light in the room as its energy, receive a variety of radio signals such as information, and update these contents anytime and anywhere, so as to really keep them fresh and rich in information, and can check and update the required contents at any time according to everyone's needs. Therefore, it can be said that this newspaper will never be out of date

3. Omnipotent book

nowadays, e-books have begun to occupy the book market, but there are still ways such as display reading

Copyright © 2011 JIN SHI