A trajectory of ink drop ejected from printhead is affected by airflow generated by media moving in parallel with printhead, and dots are formed at undesirable position on a paper. Ink drop becomes smaller for high image quality, or relative moving velocity of paper and printhead becomes higher for high speed printing, this problem will be serious.
In this paper, the trajectory of flying ink drops was analyzed by computational fluid dynamics under the model where paper moves, and the change of orbit was accounted by investigating airflow conditions. In the simple case where single drop was ejected from a nozzle, dot position error dependencies on drop initial velocity, drop volume or paper moving velocity were examined. Relative displacement among dots formed by various volumes of drops was also studied. In the case where ink drops were ejected from multi-nozzles continuously, the effect of print pattern to dot displacement was examined. It also became clear that the effect of print pattern depends on nozzle position. The explanation of this dependency on print pattern or nozzle position was attempted by analyzing the airflow change caused by colliding against continuous ink drop flux.

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In this paper, we present and discuss an estimation method for the life expectancy of optical disks using statistical analysis in order to apply a rough clarification of archival grade disks based on the international standard method. The performance of this international standard method for optical recordable disks was examined experimentally using the Eyring acceleration test with new four stress conditions and statistical analysis. Results demonstrated the capability of this method for estimating a rough clarification of archival grade disks.

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We are involved in complete removal of VOC (volatile organic compounds) by the use of thermally generated holes in oxide semiconductors. In the present investigation, we have studied VOC decomposition characteristics of Cr₂O_3+x (0<x<1) in a fluidized bed system, as well as in a honeycomb-like cartridge system which includes 15 mesh disks coated with Cr₂O₃ powders. In both systems, Cr₂O_3+x is found to exhibit an excellent decomposition characteristic which even exceeds that of the TiO₂ system, although the specific surface of Cr₂O_3+x (3m²/g) is only 1/100 of powdered TiO₂ (298m²/g).

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[in Japanese]

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Inline UV Casting & Foiling System installed on B2-Size High-Speed Multi-Color Offset Presses RYOBI 750G Series/RYOBI 750 Series performs holographic coating or foiling coating, simultaneously with offset printing. Major features are as follows.
1) Holographic coating or foiling can be accomplished inline during printing.
2) Space-saving inline installation on the RYOBI 750G/the RYOBI 750 Series.
3) The UV lamps of this system can also be used for the delivery section. Replacement is easily accomplished in about 3 minutes.
4) The grippers reliably transport the paper, enabling holographic coating or foiling with stable register precision.
5) The lamp unit remains in a raised position when not performing holographic coating or foiling.

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Hologram is recorded into the recording material as the interference fringes using object light from the objects having the information of phase and amplitude and reference light. The hologram image can be reconstructed as the complete 3D image with the information of distance.
There are two types of hologram, one is the embossed hologram that the interference fringes are recorded on the surface of the material and the other is the volume type hologram that they are recorded in the material as the dispersion of refractive index or transmittance. CGH (Computer Generated Hologram) is the recent technologies of the embossed hologram which is microfablicated the interference fringes as a concabo-convex shape using EB (Electron Beam) lithography system. Then the interference fringes are calculated with both the object beam from 3 dimensional data of CG (Computer Graphics) and reference beam using computer. Lippmann hologram is the recent technologies of the volume type hologram which is recorded the interference fringes into the volume type recording materials using laser beam. It has the good color reproducibility and 3-dimensional image is realized.

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The vacuum forming (or compressed air forming) has been used from old times in Japan. In this procedure, the material processed into a plate or sheet in advance is formed into a specific product by softening by heat and by applying a male or female die with a compressed or vacuum force. This forming method originated from the low temperature compression forming (“yushibori kako” in Japanese) of the celluloid sheet. By improving the disadvantages of the vacuum or compressed air forming, the Next Generation Forming (NGF), innovative forming method comparing with existing vacuum or compressed air forming, has been developed. In addition, the most advantageous feature that no vacuum hole is required in this forming method has been further improved to develop the Three-dimensional Overlay Method (TOM). The progress and the future prospect of a series of the development will be reviewed in this article.

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In recent years, inkjet textile printing is being employed, which enables us to respond to quick delivery and various kinds of small amount of order, comparing to traditional screen textile printing. Inkjet textile printing should comply with specific demands, such as safeness to human body and wash-fastness, in addition to conventional inkjet printing technology. In reactive and acid ink, improvement of dye solubility and anti-precipitation measure are crucial. And sedimentation control and preventive measure for crystal-growth are indispensable in dispersed dye ink. In this report, we would like to discuss how to tackle above-mentioned technical issues and future prospects.

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