One of the recent technology trends in paper for offset printing is reducing environmental impact. Methods include development of technology to utilize deinked pulp, improvement of the paper recycle ratio initiated by the Japan Paper Association, expansion of afforestation, utilization of wood resources from certificated forests, energy saving in manufacturing paper products, fuel conversion, etc. To promote utilization of deinked pulp, an ultraviolet (UV) breaker has been developed to remove UV ink and subliming ink in which a hyper-cell floatator is used to remove ink efficiently, and a de-sticking agent is in use to remove stickiness effectively. The target recycle ratio for paper in 2010 was 62%, and it was achieved in 2008. The goal for 2015 is 64%, which is thought to be difficult, and cooperation of the paper industry, consumers, and paper recyclers is needed. The area of afforestation is increasing yearly in the world to produce forest resources. Some of the wood chips are obtained from certificated forests which are managed sustainably. Black-liquor-containing wood components, waste timber, waste car tires, and waste plastics are being used to generate energy in order to reduce the consumption of fossil fuels in manufacturing.

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The print industry has evolved with the development of civilization and the world economy. However, the environment that surrounds the print industry is changing owing to a number of influences such as slowdown in world economic growth, problems in electricity supply due to the Great East Japan Earthquake, and digitization due to the rapid expansion of IT technology. The ink industry has pursued active development to achieve environmental harmony by producing aroma-free (AF) ink and soy-based ink. Now, a new environmentally harmonious type of offset printing ink is being developed. It is evolving to realize CO₂ reduction and recyclability and to conserve resources, energy, and petrochemical materials. In the present paper, I discuss vegetable oil ink and the rice oil ink using local Japanese-produced rice bran oil and high-sensitivity UV-curable ink for energy saving.

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During the last few years, fountain solutions have been improved in response to requests owing to the following.
1. Amendment of the Water Pollution Control Law.
Nitrate-free and ammonium-free fountain solutions began to be developed.
2. Compliance with the Ordinance on the Prevention of Organic Solvent Poisoning to reduce bile duct cancer.
The changeover to IPA-free fountain solution has not made much progress.
3. Fountain solutions corresponding to high-sensitivity UV printing using LED-UV lamps or UV ozone-free lamps.
Fountain solutions have been improved for pH stability and scumming of the dampening rollers.
4. Response to problems caused by the degradation of paper quality by reducing printing costs and increasing importation of paper.
Specific scratch scumming is increasing rapidly. Scratches occur due to sand grain contamination in the printing paper. It has become possible to suppress this scratch scumming with fountain solution. Over the past few years, newly developed fountain solutions have been able to suppress blanket piling. Blanket piling is caused by small amounts of ink on non-image areas that bleed onto the image. The new fountain solution can suppress blanket piling by reducing this unwanted ink.

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Recently, environmentally friendly computer-to-plate (CTP) systems have attracted attention, and they have been studied actively to reduce the waste alkaline developer generated in the processing step. There are three ways to reduce alkaline waste: (1) reducing the used amount and waste amount of alkaline developer, (2) using alkaline-free developer (reduction in replenishment solution), and (3) using a process-less system. (1) involves concentrating the alkaline developer solution, lowering the pH of the alkaline developer, concentrating waste alkaline developer, and reducing the frequency of developer-exchange (elongation of bath life).In regard to items (2) and (3), various systems have been proposed, but they cannot play a main role in a CTP system because they cannot reproduce perfectly the performance of current CTP systems using alkaline developer. Hereafter, we expect to increase the level of performance of both alkaline-free and process-less systems.

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In Japan, the number of sheet-fed offset presses using power-saving ultraviolet (UV) -curable ink have been increasing dramatically in recent years. As a result, "on-demand handling" for short-run print jobs and "added-value printing" with varnish coating or special substrates are also increasing. Power-saving UV and light-emitting diode (LED) -UV curing systems are mostly used by commercial printers with no previous experience in UV printing, and these systems are successful innovations for print production, sales, and management. The shift from oil-based ink to UV-curable ink eliminates color change due to drying after printing, and it realizes numerical color management. Decreased paper waste and gang printing reduce cost and improve competitiveness of short-run offset printing. Several in-line systems for print quality management, e.g., automatic registration, defect inspection, and color control, have recently been developed. In the near future, production systems integrating both offset and digital printing will be needed for print orders. This means that on-demand handling of offset printing will be increasingly important.

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Improvements in the quality of printing plates in all printing methods have resulted in better ink and paste printability, and new printing techniques have improved performance. The quality of a screen mask as a printing plate for screen printing is determined by the screen mesh. A stainless steel mesh has been used in the electronics field for over 50 years. Higher mesh counts and higher strength have improved the quality and performance of the screen mask. Today's stainless steel wire is 2.5 times stronger and can be woven more densely into a 40% open area mesh that is optimal for fine line printing. This screen mask is called the "no-distortion screen mask." The no-distortion screen mask that is stretched under higher tension has solved previous screen printing problems such as "snap-off" and "distortion." In the future, more high-viscoelasticity pastes that are optimized for the no-distortion screen mask will be developed in the electronics field. It is expected that any company will be able to use these high-quality screen printing techniques as standard process in the electronics field.

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We have developed a series of silk screen inks for optical applications in smart-phones and introduced them to the market as the REXWIN® series. REXWIN UA is an ultraviolet (UV) -curable adhesive for laminating transparent sheets, and it provides excellent visibility. REXWIN SB provides an excellent light shielding effect. REXWIN UD, which is a UV-curable ink for light-diffusion sheets, has useful properties for making fine patterns. Further, REXWIN SBF shows unique properties that are compatible with insulation and conductivity.

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The use of flexographic printing with an aqueous based nano-silver ink to form conductive lines was studied on three substrates (resin coated paper and white and clear polyester films).The objective was to evaluate the feasibility of using this printing technique to achieve printed conductive lines with a lower resistivity and a good printability. The effects of varying the anilox line screen and the printing speed on the resultant print quality, including the measurement of the ink film thickness and its resistivity, were investigated. The results revealed that varying the anilox line screen alone over the range of 300 -700 lines per inch (lpi) did not correlate well to the obtained print quality, whereas increasing the printing speed gave better resolution and uniformity of the printed conductive lines. From this study, it was found that using a 600 lpi anilox screen and a printing speed of 60 m⁄min were a suitable printing condition on these substrates, achieving the smallest printed line width of 0.1 mm with only 5% width spreading. However, the silver coverage was low at 0.53 g⁄sq.m at a thickness of about 1 micron with a corresponding high sheet resistivity of 4.1 W⁄sq. Since the printed silver layer did not significantly affect the surface roughness of the substrates, then increasing the amount of silver coverage by multilayer printing to improve its conductivity is possible. To this end double printing was found to reduce the sheet resistivity to 0.19 W⁄sq. and so multilayer printing may be an option to obtain a low sheet resistivity, even the limitation of this technique is low printing speed. In addition, the conductivity of the printed lines was stable at least a week at 40 or 5 °C.

Keywords: Flexographic printing, nano-silver ink, conductive ink, printed electronic, RFID

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The 3D images became well known following the commercialization of 3D television and 3D movies. However, because many methods need wear the special glasses, the glass-free 3D image displays are required. As a conventional technique, a step shading barrier is proposed. However, a cross talk and intensity moire occur by the step shading barrier. A comfortable stereoscopic vision cannot be got for these reasons. In this paper, we proposed a method to suppress the cross talk and generating of intensity moire. First, a barrier with a slanting line shape opening is made to suppress generating intensity moire. Next, the barrier with less cross talk was designed compared with the conventional technique. Based on the proposal method, a glasses-less 3D display system was made. By the observation experiment using this prototype system, it was confirmed that the proposal method can show a glasses-less 3D image clearer than the conventional method.

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In recent years, the demand for high-speed, high-definition book-scanning technology is increasing. In response to this demand, Dai Nippon Printing and the University of Tokyo have developed a book scanner that scans books at the rate of 250 pages per minute. This book scanner has a hybrid sensor composition for high-speed three-dimensional sensing and a high-resolution camera that recognizes the optimal moment for accommodative electronic imaging as it scans a book. This scan is performed while flipping the pages of the book smoothly, not step-by-step. This report describes the performance of the book scanner that we developed and the technology for realizing it.

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Japan Federation of Printing Industries (JFPI) has been publishing and updating guidelines as well as providing seminars to improve work environment of printing factories. Furthermore, JFPI has recently established a voluntary environmental guideline in the printing industry "Green Printing Certification Scheme" to promote industry-wide efforts on environmental issues. Meanwhile, the incident of high risk bile duct cancer and the death of employees in proof printing companies have triggered further survey on work place safety by JFPI. In order to deal with this issue, JFPI established "Labor Health Seminar" in cooperation with academic experts, work safety specialists, printing industry organization representatives, and printing materials organization & vendors in June 2012. The seminar has ensured the industry-wide implementation of "measures to prevent health disturbance caused by chemical substances" and helped to improve the work place environments.

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