Generally, Flexible Printed Circuits (FPCs) are made of polyimide (PI), because of its excellent heat resistance, flexibility, size stability, and surface smoothness. Metallization on PI substrate are used for high density flexible printed circuit formation. In this study, we have focused on how to achieve good adhesion between the PI and the electrolessly deposited copper without micro-roughening. Adhesion strength between PI and plated copper showed about 1.0kN/m by UV irradiation for one to three minutes. A modified layer of a depth of about 150nm was formed on the PI surface by the irradiation of UV light. Adhesion was derived from the nano-level anchor effect by the formation of co-existed layer between the modified PI surface and the deposited copper. Moreover, selective and fine copper patterns were also obtained using selective UV light irradiation and conventional copper plating.

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A thick platinum metal layer was deposited on ceramics using electroless- and electro-plating. The ceramics, which consist of ZrO₂, Al₂O₃, SiO₂, Na₂O, and other oxides, were etched in HF solution, and then immersed in a platinum electroless plating solution containing Pt(NH₃)₂(NO₂)₂ and N₂H₄ as a reducing regent. The mass of the ceramics specimen decreased slightly with the electroless plating time and then increased at a rate depending on temperature, but independent of Pt²⁺ concentration. A2μm thick platinum layer could be deposited uniformly on ceramics by electroless plating for 14.4ks at 323K. Electroplating of platinum in Pt(NH₃)₂(NO₂)₂ solution after electroless plating caused the formation of a platinum layer as think as several tens of microns, and many cracks were formed on the platinum layer after a long period of electroplating.

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In this research, it is aimed to control the flow velocities of some liquids by surface energy control on the channel of a chemical chip substrate.
Chemically adsorbed monolayers were used to control the flow velocities on a Y shaped channel of a chemical chip substrate. Five kinds of glass substrates covered with chemically adsorbed monolayers of a fluorocarbon compound, two hydrocarbon compounds, and two mixture compounds of those were made. With the use of Zisman's plot, the surface energies were determined on these glass substrates.
In measurement of the flow velocity, three chemically adsorbed monolayers having different surface energies were chosen. Each of the chemically adsorbed monolayers was selectivity formed on one side of the branching channels to control the flow velocity, and not on the other side. Xylene, methyl benzene, and tetrabromoethane were respectively injected into the channel of the chemical chip substrate, and relationships between the surface energy and the flow velocity of the liquids were measured. The flow velocity increased with increasing the surface energy of the channels. It was shown to be possible to control the surface energy of the channel without spoiling the channel function by the chemically adsorbed monolayers, and to be possible to control the flow velocities of the liquids on the channel of the chemical chip substrate by surface energy control. It was confirmed that the effect of the surface energy became stronger with decreasing the liquid viscosity.

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