Presensitized offset plate and waterless plate have been improved to satisfy various requirements of the printing industry such as high quality, unskilled labor, environment protection, etc. High definition printing and frequency modulated screening are drawing the attention as new technology. In recent years, the field of digital direct printing has seen remarkable development. This paper describes the foundation and progress of these presensitized offset plates.

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During the recent two decades UV curing technology has been widely adopted in various fields of the graphic arts market. This review describes several formulating points of UV curable inks that have to be considered, which include litho-printability of offset inks, the gloss-back problem of the overprinting varnishes/coatings at the in-line application, and adhesion problem of the screen inks. Some important characteristics of the latest applications such as UV waterless offset, UV curable waterbased inks and UV flexo inks are also mentioned.

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Among technologies for color filter (CF) fabrication, pigment-dispersed color resist (PDCR) photolithography is dominant over all others in commercial manufacture of large, fine-resolution CF for liquid crystal displays. Application of several photochemical transformation systems to PDCR is examined to result in the discovery of a chemical amplification system, based on acid-catalyzed cross-linking, has an advantage of high-resolution. The resolution capability of PDCR is directly related to the resist contrast (γ) the same as the case of resist for semiconductor fabrication. The contribution of a certain pigment on photo -initiated radical reaction is also revealed.

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A. C. impedance measurements were applied to study a stability of W/O emulsion. Measurement frequency range was from 10mHz to 100kHz. Diameter of aqueous phase changed smaller with increasing of agitating power at emulsification. Emulsion was observed by Cryo-SEM. The impedance at low frequency showed the whole resistance of emulsion. It was about equal to oil phase resistance when water phases were surrounded with oil phase respectively. Coalescence of emulsion has grown at 60°C faster than room temperature. It's change can be detected by decreasing of impedance at low frequency and obsurved by Cryo-SEM.

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The principle of reproducing image by halftone printing as well as that in continuous tone color photography is supposed to be subtractive color mixture. Light absorbance is proportional to the rate of dot area. And light reflectance of piled solid printing approximates to the product of reflectance of each color solid print. By applying these two assumptions to the color that is producted by superimposing different color dot, it is proved that the principle of reproducing color image by half tone printing is subtractive color mixture. This was already proved by using the measured value of color filter density in the first paper. In this paper we prove it by using the measured light reflection value of halftone printing.

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This paper describes a simple method to verify handwriting mainly based on up-down pen movements of writing process. Many schemes have been proposed for on-line handwriting verification, and it is known that reliable recognition can be reached if we use various kinds of information such as the velocity and acceleration signals of a pen, the force on pen tip and the gripping force of a pen, and so on. Special devices, however, are required to obtain these data. For practical use, it is desirable to use data which can be obtained easily by simple tools like a touching panel. Therefore, the authors have considered trustworthy handwriting verification using as less data as possible. As the result, high recognition ratio was obtained by the use of timing of pen-up and pen-down, and directions of first and last movements of each stroke of Kanji characters representing one's family name. Practical and reliable person verification can be realized by the use of both this method and other simple verification information such as identification number.

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Many kinds of hardcopy imaging systems have been developed and the image quality of these images has improved greatly. Therefore, engineers and designers in the printing industry are showing an incleasing interst in using these hardcopy systems as the proof press instead of conventional printing proof. Two standard color images with test chart were reproduced using 16 kinds of printers; laser printers, sublimation printers, silver halide printers, on-demand type thermal printers and inkjet printers. Color reproduction and resolution of these images were measured and analyzed. The images were then rated by 18 designers and engineers from the printing industry. In that follows, the problems of present hardcopy systems for usage as the proof press in printing are discussed. It is the purpose of this paper to describe the capabilities of direct proof in present hardcopy.

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Development of computers led to computer type-setting (CTS), enabling text data to be processed by computers. Once data are stored in a computer, they can be easily rearranged or transformed. Use of computer's various functionalities in processing data as such changed the way to produce dictionaries or magazines. Further advancement of computer's processing power in recent years made it possible to process text, graphics and images in an integrated manner. It innovated in the forms of manuscripts and the methods of proof-reading, thereby contributing to the reduction of time and cost in producing printed matter.

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