In order to reveal the scope and limitation of applicability of our kinetic tribocharging model for the two-component developer in which the tribocharging process was an equilibrium of the transfer of charge between the toner and the carrier, our model equations were applied to some reported data which were determined to be not consistent with the linear relationship between the reciprocal of toner charge-to-mass ratio (q_e^t) and the toner-to-carrier ratio (m_t/m_c = C_t), 1/q_e^t ∝ C_t. Consequently, all cases tried were consistent with the equations over extremely wide ranges of C_t, whereas in the small C_t region, C_t < 0.01, plots slightly disagreed with the model equations. On the other hand, it was demonstrated that the adhesion of the toner materials to the carrier and the wire-net for the blow-off measurement and the passage of some carrier-particles through meshes of the wire-net could not be avoided and neglected in the small C_t region. These results strongly suggested that the disagreement in the small C_t region was due to the experimental error in the blow-off measurement.

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Human visual system is capable of seeing over five orders in magnitude simultaneously and can gradually adapt to scenes with high dynamic ranges of over nine orders in magnitude. The current display device, such as CRT, can not reproduce the dynamic range more than 100: 1. This paper proposes a novel method to improve the image appearance based on Retinex model using Integrated Surround. The first novelty is that several number of surround images are integrated and unified to a single surround. The integrated surround is applied to Center/Surround Single-Scale Retinex (SSR) model, which reduces a “banding artifact” seen in normal SSR and simplifies the complicated computational steps in conventional Multi-Scale Retinex (MSR). The second novelty is its fast algorithm to generate the surround images. We introduced Gaussian Pyramid method to cut the computation time for generating a large-scale surround by tracing a “reduction” and “expansion” sequences using down-sampling and up-sampling followed by linear interpolation. The computational expense is dramatically saved less than 1/100 for getting a surround by Gaussian convolution with large-kernel size. The proposed model worked stable to compress the dynamic range and to improve the visibility in heavy shadow areas of natural color images.
The paper discusses the scales and weights to integrate the surround images and presents the color reproducibility measured for a synthesized target image on monitor screen visually matched to a real scene set in our experimental room.

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Corona discharge is affected by various factors. Siloxane gas is known as one of influential gases to the corona discharge. The voltage to maintain corona current constant is monitored as a function of time. When siloxane gas is blended to air flow to corona discharge area, the voltage increase is observed. Siloxane gas is blended in the duration of 30 minutes after 30 minutes when discharge is stared. In the duration, the voltage increase is observed and the voltage decrease is observed just after the stop of the siloxane gas blend. From the increase and the decrease of the voltage, two mechanisms of the voltage change are considered as wire degradation and discharge restraint by siloxane gas itself.

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The purpose of image quality evaluation is optimizing a specific imaging system to human visual system. And many image quality measures showing a good correlation with psychological factor of image quality (image quality attribute) have been developed in various imaging systems such as graphic arts, silver halide photography, television and electro-photography.
As the international standardization of image quality evaluation, the standardization of a physical measurement method for quantifying an imaging system with a common measure has mainly been advanced. Recently, standardization of the measurement method of image quality attribute showing a good correlation with subjective evaluation has been advanced.
ISO/IEC JTC1//SC28 (Office Equipment) has been developing international standards that can measure the image quality attributes for hardcopy output. ISO/IEC 13660 entitled “Measurement of image quality attributes for hardcopy output” provides basic definitions of image quality attributes for binary monochrome hardcopy outputs, and has a significant impact in the office equipment and printing industry. ISO/IEC 13660 is the first international standard which specified a set of image quality attributes although it has some issues on the variations in measurement values or the mismatching with subjective evaluation.
This paper describes the current status of an improvement of ISO/IEC 13660 which JBMIA SC28 as the Japanese representative of SC28 takes charge of, and the development of “Appearance based image quality standards for printers” which INCITS W1 as U. S. representative of SC28 takes charge of are reported.

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EU has been promoting an environmental conservation of the earth with a magnificent vision and goal also in the field of environment while driving a strategy to become the most competitive economic bloc in the world by 2010. Environmental policies, strategy, action plan, regulations and EU harmonized standards are taken into account to enhance their consistency, and various methods are adopted to promote the environmental action plan. Of such methods, effective methods are chosen to evolve their effectiveness in a wide variety of other fields. Looking at trends significantly coming out from environmental policies on products development, it will be necessary for those operating their business in EU in the future not only to implement environmental conservation activities taken to date mainly in production sites but to expand their activities also in the stages of material procurement, designing, production, marketing, product collection to recycling while taking into account product life cycle. Since environmental regulations enforced in EU last several years has been implemented under such background and aims, a fundamental direction of EU regulations seems to be unchanged but they will probably be accelerated furthermore in the future. Therefore, manufacturers need to realize such fundamental direction to promote development of their products while setting high environmental targets on a routine basis so as not to rush into an immediate countermeasure after a regulation is enforced.

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In electrophotographic machines, a fuser portion consumes almost all electric power. And the power consumption at standby state is larger than that of operation state. Therefore fusers that can be heated-up rapidly have been developed to reduce electric power. Strong heaters and fusers with low heat capacity are required for quick warm-up fuser systems. On the other hands, in the low heat capacity fuser systems, excess temperature rise at the both ends portion of the fuser roller inevitably occurs when smaller sized paper is continuously printed. This phenomenon reduces printing productivities. This paper introduces recently announced energy-saving type fusers.

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The copying machine and printer based on electrophotographic technologies has added much technical development of energy saving and ecology for considering the environment. Recently, in office use, a viewpoint how to lose futility is demanded. Now, we'll discuss EP Imaging process technologies that considered the ecology, based on the following items. The first discussion is the long-life technology of OPC (organic photoconductor) and a-Si (amorphous silicon). The second discussion is changes and the present condition of technology, such as how to reduce the spent toner and a cleaner-less system.

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Recent environmental regulations and CO₂ exhaust control based on Kyoto Protocol have a great effect on not only basic industries such as steel and automobile but also business machines and home electric products. Also the movement of saving natural resources and energy has been promoted much stronger by public agencies, enterprises and homes. These tendencies has been established by rise in raw material prices such as petroleum and problem of constant increasing CO₂, and Japan, who has been a top runner on smaller products, saving energy and antipollution, is expected as a leader of these movements in the international society. Toner and developer for Xerographic copiers and printers also need environmental considerations under the above tendency. The hardware makers are concentrated their powers on energy saving, resource saving and the preparation for future environmental regulations. This paper describes an outline of recent stream of new process toners considering environmental issues.

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Reconditioned copier is developed from the basis for the concept of circulating society realization. It meets most recent safe standard and acquired some environmental label even though it is produced with more than 80 weight percent reused parts. For mass-producing reconditioned copier, we try to increase the rate of reuse parts and reduce the cost, by constructing product recovery information system, producing recondition and diagnosis technique. Furthermore, We tried to make a research on environmental load in life cycle process of this reconditioned copier from the view point of Life Cycle Assessment. As the result of our research, we conformed that reconditioned copier reduced a lot of environmental load in comparison with new manufacturing.

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A novel disposal system of plastic wastes has been developed, utilizing thermally-generated holes in TiO₂ at high temperatures. Any polymers such as thermoplastic as well as thermosetting ones can completely be decomposed into CO₂ and H₂O at the interface between TiO₂ and polymers. The present technology can also be applied to the disposal of medical wastes, odors, dioxins, as well as exhaust of diesel engines.

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