Alkaline papermaking technology has recently increased the life span of paper. However, to develop permanent paper that has a life span of more than 1000 years, it is necessary to clarify the factors that influence age resistance such as brightness reversion and strength deterioration. This paper provides a brief explanation of aging resistance specification and reviews recent research on the influence of paper components, storage conditions, and printing ink on aging resistance.

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The ink business world is unified to be benign to the environment. During the decade of 1990-2000 year, ink raw materials changed greatly. There was a change to substitute soybean oil for petroleum solvent. It was decided to change more than 50% of ink raw materials while maintaining good printability. This report explains the way to realize that goal. Then, it is explained that the characteristics of pigment and the action of water with the printing machine have an influence on the printing quality.

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To obtain ISO certification has been the matter of concern to the printing industry. On the other hand, there is the possibility that we cannot focus on enhancing quality when we stick to obtaining ISO certification too much. In this article, we will consider the concept of improving printing quality in the wake of obtaining ISO certification.

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There are usually quality specifications which can be expressed numerically for industrial products. But, there are no such specifications for printed matters. By this reason, various quality problems are evoked between the manufacturers and the clients. Here, I would like to discuss about the present status and problems of the print quality.

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In Japan, gravure is the most common process for plastic package printing. However, this causes a financial problem to gravure companies and environmental problems to the society. There are several factors in this gravure business problem, such as excessive competition among gravure companies due to oversupply, a high quality demand by clients that neglect the quality standard of raw materials such as ink and film and request the standard arts and crafts rather than that of industrial products. In Japan, some one thousand defect-detectors have been used in-line and off-line in gravure printing. At present, the quality standard in gravure printing seems too high as the prints having stains and alien substances undetectable by these defect-detectors are classified as “inferior”, and sometimes clients demand a high quality level than that of bill printing. For further development of the gravure industry, it should take the following points into consideration, not caring only about the appearance of packaging and wrapping materials: 1. To gain confidence from clients by preventing the inclusion of impure materials such as bugs, hairs and others. 2. To establish common rules among clients, designers and gravure companies through information technology. 3. To put priority on ecology in concert with the clients to prevent pollution of the environment through solvent recovery and treatment as well as use of water-based ink.

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Full Pagenation System in Japanese newspaper industry had been developed as Total CTS since late '60s. Japanese Publishing System (JPS) architected by Federal Systems Division of IBM was the first product in this area. JPS was equipped with digital fonts, halftone screening, sharp-unsharpe technologies, and so on. Author have engaged in Next-generation JPS project named NPS, and learnt newspaper production issues. This paper reports some characteristic standards of Japan newspaper industry, and their historical backgrounds.

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Material structure and properties of the rewritable imaging plate consisting of the super-ink-repellent surface and the principle of the proposed variable printing process with the plate are reported in this paper. Fluoro compound and two kinds of SiO₂ particles in the plate material give the super-ink-repellency. Partial concealment of the super-ink-repellent surface by placing certain kinds of hydrophilic organic materials forms latent images on the plate. The organic materials on the plate can be washed out with water. And the plate recover the initial status by drying which is fully covered with the super-ink-repellent material. The formation and erasing processes of the latent image can be repeated. An ink-jet imaging procedure is employed for placing the organic materials on the plate. The plate having the latent image is dipped into water based ink. The latent image is developed by the ink where the organic materials are placed. And then, the ink on the image of the plate is transferred to paper. The plate is recovered to the original status by washing and drying. The authors have examined the processes of the latent image formation, the ink developing and the transferring, and the plate recovering processes, and have confirmed that all processes have been properly performed. Finally, fine ink image sample transferred to paper has been obtained.

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We sometimes can recognize color components that should not be possible with two color prints using two color inks which is a common practice of simplified color printing. The reason for this type of color recognition was discussed in an earlier paper. This study aims to clarify which type of two color set shows this specious full color impression most fully. Subjective tests that examined color impression of various two-color prints were carried out. Prints using cyan and red inks show better performance (fuller color impression) than prints using blue and red inks or green and red inks. The last of which are often used in commercial press prints.

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Recently, photocatalysts have attracted much attention for their application to decompose environmental pollutants and to cleave organisms and bacteria, and also to produce new imaging materials. This paper reviews an outline of property and preparation of photocatalyst, especially TiO₂, and shows the preparation of hydrophobic-hydrophilic micropattern using photocatalyst and irradiation of UV light. The possibility of the application of photocatalyst to imaging materials is also discussed.

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Gravure and flexo inks are used for various purposes, and are required to satisfy various quality specifications. Therefore, they are evaluated with various measuring methods. The quality of gravure and flexo inks should be stable and of excellent printability and suitability for usage. The proper measuring methods of the inks are the first step to get excellent print. These measuring methods are mainly classified into four categories, (1) ink characteristics, (2) printability, (3) printed ink film properties and (4) converting process properties. This paper presents an outline of (1), (2) and (3).

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