Equivalent viscosity of Electro-rheological fluid (ERF) increases extremely when an electric field is applied across the fluid. ERF has a dielectric oily liquid base in which fine solid particles are suspended with small amount of surface active agents to prevent gravitational settling. A jet of this ERF is produced by forcing ink under high pressure if no electric field is applied across the fluid. When the electric field is applied, the ERF ink is not ejected from the nozzle because of its increased viscosity. Therefore, droplets generation of this ink can be controlled electrically. High printing quality and light fitness are expected to this type of DOD inkjet system, because the composition of ERF is similar to that of printing ink. We showed AC electric fields is preferable to control droplet ejection of the ERF ink jet system experimentally. When 500 Hz AC square voltage wave form is used, the maximum droplet generation rate obtained is about100 dps.

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We have been studying the melt-type laser induced thermal transfer printing using a high-power laser diode. In this paper, it is discussed that this laser printing method is suitable to be applied on the full-color printers. There is one important problem that efficiencies of exchanging form energy of laser beam to heat is small for absorption coefficients of color ink layers. This problem could be solved with settling the light absorption layer between polyester film and color ink layers.
As a result of the experiment using a double-1ayer color ink sample, minimum line width was 10 μm that corresponds with the resolution of 2,540 dpi, and printing energy was 0.83 J/cm². This printing method is suspected to be possible to use of the full-color printers.

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Decomposition efficiencies η of SiH₄ and the related gas M in SiH₄-M-Ar glow-discharge plasma sustained by Ar carrier gas for fabrication of hydrogenated amorphous-silicon alloy (a-SiX:H) have been measured by mass spectrometry, where gas M is Si₂H₆, SiF₄, GeH₄, C₃H₈, C₂H₆, C₂H₄, C₂H₂, CH₄, CF₄, NH₃, or CO₂. Relative rate constant of dissociation reaction of gas M to SiH₄, K_d,M/K_d,SiH4 determined from η_M and η_SiH4 enables to correlate with the lowest thermodynamic dissociation energy ΔH of the gas M by K_d,M ∝ exp(-ΔH/1.10). Relative in corporation probability into a-SiX:H alloy of relevant radical R for the gas M to SiH_n (n = 0-3) radicals for SiH₄,γ_R/γ_SiHn has been estimated using the film-compositions [X] and [Si] in the a-SiX:H alloy and decomposition efficiencies η_M and η_SiHn in the plasma, where a-SiX:H alloy is a-SiGe:H, a-SiN:H, a-SiC:H, or a-SiO:H. The variation in γ_R/γ_SiHn is at most three times, while that in K_d,M/K_d,SiH4is of two orders of magnitude.

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The potential distribution in the development zone of an electrophotographic copying machine is analysed using finite element method (FEM).
In the calculation, a finite rectangular wave form pattern is assumed for the latent image on the photosensitive film. It is found that while the potential reaches a maximum at the center of the charged regions of the rectangular wave form pattern, a maximum also exists in the uncharged regions and that it shifts to the development space. At the same time, the electric field reaches a maximum outside the outermost charged pattern. In moving along the surface of the photosensitive film from the center of a charge region to that of the uncharged region, the field charges its direction by180°.
A new equation for evaluating contrast potential is deduced. The effect of bias voltage, ratio of dielectric constant of the film and that of the development space, film thickness, and contrast potential are descussed.

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