Fundamental aspects for low- and medium-vacuum regions are described. Some long-standing problems, such as slip flow, pumpdown curve for viscous flow region, and vacuum drying are presented. The importance of slip velocity at a pipe wall for the Knudsen number between 0.01 and 0.1 is enlightened. A numerical result for a pumpdown curve with a pressure dependent conductance in the viscous flow regime was presented with an emphasis on a t⁻¹ pressure decrease. In addition, vacuum drying process is modeled with a water containing capillary and pressure dependent mass flow is discussed.

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  The unique properties of diamond like carbon (DLC) film, including its chemical inertness and impermeability, make it possible for new applications in food and beverage.
  In this paper, I summarize and review the recent progress of gas barrier enhancement of polyethylene terephthalate (PET) bottles for beverage from the view point of the application of DLC coating.
  A unique technique of plasma CVD method has been developed to deposit DLC layer on the inside surface of PET bottles. The DLC-coated PET bottle exhibits extremely high gas barrier properties against oxygen, carbon dioxide and flavors compared to conventional bottles.
  For the practical use of PET bottles as a commodity, high speed and low cost coating are essential; accordingly several high speed coating machines with a capacity of up to 18000 bottles per hour have been developed, and successfully operated so far for a large production of soft drink. Low speed machines have also been introduced for wine, Japanese sake, edible oil, seasonings and others.

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  Energy-saving in the household refrigerators is attracting attention from consumers because their energy consumption is the largest in the home. Increasing capacity and improving energy-saving performance, which are both major consumer needs, are key technological challenges in the development of more environmentally friendly refrigerators. Energy-saving performance was improved by using vacuum insulation panels to reduce the amount of heat escaping through the insulation walls and by using high efficiency compressors to reduce input energy. Furthermore, Hitachi has achieved both high capacity and energy-savings by using unique energy-saving technologies.
  Additionally, with the rise of health consciousness, a “Vacuum Compartment” has been used to successfully preserve food items for longer.

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  The tabletop scanning electron microscope (the tabletop SEM) was developed to provide “a leading-edge electron microscope even easier to use and more accessible to people”. Combining the resolution of an electron microscope with the ease-of-use feature of an optical microscope, the tabletop SEM revolutionized the idea of an electron microscope and it is now used in a wide range of fields world-wide, including private sectors to government agencies, universities, hospitals and science museums. The tabletop SEM also plays a role in Hitachi's corporate social responsibility (CSR) activities supporting education for elementary school to college students around the world. By providing children with an opportunity to experience the micro-world at first hand, and potentially arousing their interest in science, Hitachi aims to develop human resources that are ready to work in the fields of science, technology, engineering, and mathematics (STEM).

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  We fabricated Zinc oxide (ZnO) films on a glass substrate by using RF magnetron sputtering. The effect of ion irradiation controlled by target RF power P_T and Ar pressure P_Ar on the ZnO film properties was investigated. Argon ion line intensity I_ArII near the target increased with P_T. The I_ArII was almost constant with the increase in P_Ar. The effect of ion irradiation was enhanced by increasing P_T, while the effect decreased with the increase in P_Ar. Carrier density n and hall mobility μ of the fabricated ZnO films were strongly dependent on the film structure affected by ion irradiation. For P_T=70 W and P_Ar=0.7 Pa, the lowest film resistivity ρ of 2.4×10⁻³ Ωcm was measured. The average visible transmittance T_AV was estimated assuming the thickness of fabricated ZnO films was consistently 150 nm. T_AV increased with the effect of ion irradiation. We found that the effect of ion irradiation was useful for controlling the properties of ZnO films.

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