The development of super-high-resolution and high-throughput printing technologies was necessary for the advancement of printed electronics. We investigated a microcontact printing technique for making the super-fine patterns required in printed electronics. The interfacial phenomena are essential for using microcontact printing to print super-fine patterns. An all-printed organic thin film transistor (TFT) array (200 ppi, 192 M transistors, 10 inches in size) was successfully fabricated on a polymer film by printing silver nano-particles as a conductive material, poly (3-hexylthiophene) and⁄or its derivatives as a semi-conductor, and organic dielectrics as an insulator. For high-throughput production, new printing methods are proposed: screen-offset printing and wet-on-wet printing. We attempted to fabricate sensor grids for touch panel devices and organic TFT arrays by using a screen-offset printing technique and wet-on-wet printing technique, respectively.

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Unlike other general printing methods, because the mask inking mechanism in screen printing is based on the so-called "first in, first out" principle, the ink in the mask is unlikely to dry out. Thus, screen printing is able to consistently print the high-viscosity, functional pastes used in electronics. In order to print with high precision, a screen with a high mesh count and fine wire diameter is required, but, until now, such screen meshes have been problematic in terms of insufficient strength. Recently, however, the "non-distortion screen mask" was developed and commercialized. This is a screen with an extremely high mesh count of 650 and 2.5 times the strength of conventional screen meshes. This "non-distortion screen mask" is ushering in the "third generation" of screen printing, which will allow anyone to achieve high-quality screen printing; this will contribute toward speeding up the commercialization of printed electronics.

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Screen printing for solar cells has continued to evolve rapidly. The Ag paste used for printing the front side of a solar cell requires both fine-line and fire-through control. It is necessary to thoroughly understand this control to improve cell efficiency. A "shallow emitter" is one of the high-performance solar cell technologies. To fabricate a shallow emitter cells, it is necessary to optimize the next generation of screen printing. A shallow emitter requires an increase in the finger number, fine lines to decrease the shadow loss, and a high screen mesh. We have been able to achieve a resolution finer than 50 μm for finger lines of screen printing on a solar cell wafer using a properly tuned combination of an ultra-high mesh and a new lead-free Ag paste. For every target line width from mass production to the next generation, there are three steps (50⁄40⁄30 μ m).We propose the idea of screen spec, which provides good fine-line printing. In addition to ultra-fine lines, the new lead-free Ag paste is potentially capable of being adapted for use with values greater 100 Ω⁄□ for high sheet resistance cells (∼120 Ω⁄□).We recently obtained part of the solution for 30-μm line screen printing, which will make a 120 Ω⁄□ cell available for fabricating high performance solar cells. The end goal requires the "total optimization of the solar cell process," not just individual improvements.

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Printing technology has attracted much attention because it can create a new paradigm in the field of electronics. Among the various printing methods, screen printing is widely used for forming the wires and⁄or electrodes of electronic devices such as solar cells, touch screen panels, and multilayer ceramic capacitors. However, mainly because of ink bleeding, patterns with widths smaller than 50 μm are difficult to form using the screen printing method, which limits the range of applications. To address this issue, a new printing method called screen-offset printing has been developed. In this method, ink is first screen-printed on a silicone-resin blanket with a flat surface. The ink is then transferred from the blanket to a substrate. Because the silicone resin absorbs the organic solvents in the ink, the viscosity of the ink pattern on the blanket increases. Therefore, fine patterns can be transcriptionally formed on the substrate without ink bleeding, and the line width reaches 20 mm. In addition, the ink pattern has a rectangular cross section, which contributes toward making wires and electrodes highly reliable. In the present paper, this printing method is detailed, and its impact is elucidated by comparing the experimental results obtained by conventional screen printing and the developed screen-offset printing.

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Several printing techniques for fabricating organic thin film transistor arrays have been studied. However, conventional printing techniques such as flexo, screen, and ink jet printing show poor printing resolutions of only 20 μm or higher, which is not sufficient for high-resolution thin film transistors (TFTs).Reverse offset printing has attracted much attention recently because of its ability to make fine patterns of less than 5 μm with smooth surfaces. The key point of such printing is introduced here, along with several functional inks developed for printed TFTs. From the perspective of enabling the industrialized production of printed flexible TFTs, the key points for printing technology include a technique for fabricating fine patterns, a method for realizing precise overlays, and the construction of simple and low-cost production processes. This paper introduces a promising printing process for achieving precise pattern overlays on a flexible plastic substrate, which will significantly simplify the printing process. This is a wet-on-wet process for reverse offset printing, in which subsequent layers can be printed on previous semi-dried layers, after which all the layers are sintered simultaneously.

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Printed electronics has been required to respond to the demand for not only lower costs but also higher accuracy and finer lines. Gravure offset printing is a high-quality printing technology that makes it possible to achieve high accuracy and fine lines. The potentiality of printing technology is determined by the "equipment for securing high accuracy and repeatability," "a paste that possesses the quality required for the products and adequate processing," and "a low variation in the quality of the materials." It can raise the production process to a mature level by synergizing complementary technologies. Gravure offset printing must be a highly mature printing technology for the next generation.

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E-book in Thailand is increasing rapidly as the trend is growing along with the increasing of electronic gadget market such as Tablet, Smartphone and Kindle e-paper etc. It has less cost to produce and can be sold in lower price compared to that of paper book. Interestingly, the content can be transferred to other reading device platforms. Moreover, in the viewpoint of an environmental concern, many scientists still believe that the e-book emits the greenhouse gases (GHGs) lower than that of paper book. This research surveyed the environmental awareness and e-book reading behavior of Thai people in order to analyze its carbon footprint on iPad. The result showed that the average reading speed of Thai people was 312 words⁄min, which is slightly slower than reading a printed paper book about 16 words ⁄min. Chi-square test at 95 % significance level represented that the relationship between the selected reading devices and types of media to read was dependent one another. This implies that Thai people still prefer reading magazines on printed paper, while reading the news on electronic device. To calculate the carbon foot print of the printed paper book and its relevant electronic book, by the same number of copies and downloads, the techniques of Life Cycle Assessment (LCA) was employed. It was found that the electronic book can reduce the amount of CO₂e emission up to 63 %, or about 3 times of that emitted from the printed paper book.

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The manufacturing technology for security printing has been improved by innovations several times. As a result, the characteristics of anti-counterfeiting security printing have been enhanced. On the other hand, because security design is always confronted with new counterfeiting methods, it is important to be equipped with advanced technology to meet the demands of the age. In the third collection, I explain anti-counterfeiting technologies that have been used for security, from the photomechanical processes that began in the 20th century to the current digital imaging technology to counteract copying and replication.

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