Information security is one of the most important issues in the network society. Threats to the society such as cyber-terrorism, computer crimes, copyright infringement, privacy violation etc. will be serious if we do not take any action of improving security of the network. In this paper, we first present a conceptual framework of information security measures. Then we discuss information security technology, for which two major subjects are user identification and protection of information. Finally we survey recent trends of cryptographic techniques which play the central role in the information security technology.

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A digital watermark is secretly embedded into creative multimedia works such as document, video and audio data by the hiding techniques, and it becomes a robust proof for copyright protection issues when the works would be copied illegally. In this paper, first, we survey many watermarking techniques proposed up to now and classify them according to each media and property. Comparing them for practical use, we investigate several characteristics that enable us to evaluate whether a watermark is robust or not against some attack.

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Introduction of EC into the new infrastructure of the society can potentially cause massive changes to the total system of commerce in the future. Various experimental sessions of EC were started from last year, and its introduction to practical systems has just begun now. However, in order to promote its use in real businesses, exchange of information over Internet and protection of privacy must be guaranteed, and therefore “security technology” is quite an essential factor. This article will discuss how our encryption technology and other security technologies are applied to Business to Consumer EC systems (i.e. Internet Shopping systems), and review issues to be resolved there in terms of extension of EC business model.

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Digital image processing technology brought remarkable advancement of color copier, scanner, color printer etc. which can be bought inexpensively and wide-spread in our society and are very easy to access by everyone. Security printing industry is now encountering with a new threat of counterfeiting, in addition to conventional counterfeiting and forgery. In the computerized and automated society, security papers are demanded to have machine readable features for automatic vending machines, ATM, money changers, etc. Security printers must cope with this tendency. In this paper, present situation of security papers and security features are discussed. Conventional security features such as watermark, security thread, intaglio printing, microprintings etc. and newly developed security features such as color shift ink, OVDs, embossing, microperforation are described.

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An analytical method is proposed to investigate elastic deformations of the blanket in offset printing. The blanket is modeled to a multilayered medium of anisotropic material and the contact problem of the impression (or plate) cylinder indenting the blanket bounded to the blanket cylinder is analyzed by using the elastic theory of plane strain. The contact stresses are related to the surface displacements of the blanket by employing integral transforms and a matrix formulation approach. The numerical solutions are obtained by using a load increment method. Besides distributions of the contact pressure the numerical results show relations among the contact load, the deformation of the blanket surface and the contact width. Influences of Young's moduli and thickness of each layer of the blanket and the coefficient of friction on the contact pressure and deformations of the blanket, are examined. The experiments are carried out for measuring the contact pressure and deformations of blankets and the calculated results are in fair agreement with the experimental data.

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Rheological properties of microcapsule ink were investigated using a cone-and-plate type rheometer. The ink consists of microcapsules, of which diameter is about 2μm, and UV curable oligomers as a disperse medium. In steady shear flow the viscosity decreases with increasing the shear rate in the region under 0.05s^-1. This phenomenon is attributable to breaking down of the network structure formed by microcapsule particles under the shear. Dilatant behavior was also observed in a certain shear rate range between 0.05 and 0.2s^-1. In order to investigate the peculiar flow behavior, we measured the flow properties of various disperse systems of microcapsules having different core and shell stiffness.

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This paper explains the theories, characteristics, actual utilization, effects, and future developments of GIS (Golden Imaging Software) that is a rational and systematic digital color separation tool. Color separation techniques developed in the analog age involve many parts that are dependent on a user's sense, and therefore, are not directly applicable to digital techniques. GIS solves this problem and fundamentally clarifies intricate color separation works. The basics of color separation by GIS are to rationally and systematically adjust and manage the gradations of color plates. GIS employs a reverse color separation method to match the finish tone of a color copy with market requirements. A technical concept of color separation by GIS is to use dot percentages to express images. To convert density values into dot percentages, GIS employs NY (Numakura Yamatoya) equation whose theoretical handling has been established by the author. This paper also explains in detail the characteristic mechanisms and applications of GIS-based color separation works, as well as actual procedures of the GIS-based color separation works. Lastly, the paper explains the contribution of GIS to developing the intricate conventional color separation technique into a simple, explicit one. The paper writes that GIS is applicable not only to the fields of plate-making and printing but also to a variety of fields that handle color images.

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The development is mainly based on the advance of the semiconductor technology. Particularly the digital signal processing technology has made it possible to utilize new control method. This paper gives an outline of the control system for a newspaper printing press.

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Wet coating treatments on plastic surface have been widely conducted to give packaging materials with various functions. This paper describes the ways of wet coating to improve properties of gas barrier, heat sealability, adhesive, antistatic as well as light protection. The effects by wet coating treatments are also discussed.

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Surface modification of plastic material is necessary and important to get good wettability, adhesion, when we have converted such as printing, coating, and laminating, so on in the packaging material field. In this peport, I would like to explain each method and property in brief, which can be valuable in the Dry Process Treatment. And also a few application, transparent gas barrier films, No AC laminating technology which can be achieved are introduced.

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