The detailed understanding of the interaction between dyes and additives in the practical service condition is required to develop an inkjet ink for textiles. In the present study, the interaction between three acid dyes (C. I. Acid Red 88, 13, and 27) and a water-soluble polymer, poly(vinylpyrrolidone) (PVP), with different molecular weight was investigated. The binding constants of the dyes with PVP, K_bind, were determined by means of the visible absorption spectrum measurements. The K_bind values decreased with an increase in the number of sulfonate groups in the acid dyes (an increase in the solubility of the dyes in water). This suggests that the affinity to PVP decreases with increasing water solubility. Furthermore, the binding constants were diminished by increasing molecular weight of PVP. It is presumably due to the conformation change of PVP with molecular weight. For further discussion, the thermodynamic parameters for the binding, viz. the enthalpy change, ΔH_bind, and the entropy change, ΔS_bind, were determined from the temperature dependence of K_bind. The ΔH_bind values for all the dyes were negative, showing that the binding processes are exothermic. The absolute values of ΔH_bind decreased with the increase in the number of sulfonate groups in the dye molecules. On the other hand, the increase of PVP molecular weight made the thermodynamic process to be less enthalpic and more entropic. Thus, the nature of the interaction should be affected by PVP molecular weight, because the polymer conformation is strongly influenced by the molecular weight.

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The metal plating of epoxy polymers has been widely used in industrial products for many years, especially in printed circuit boards (PCBs). It is one of the most important technologies used to manufacture electronic devices due to its high reliability and guaranteed quality. The authors are developing a new concept of PCBs for the next decade is presented, with improved techniques for applying finer lines circuits and higher density conductor layers. An essential objective of this technology is to improve weak copper adhesion peel strength on epoxy insulation materials. The present method for achieving good adhesion of copper plating on different surface is the Pd colloid catalyst method. In order to achieve better adhesion for next generation PCBs, we used the supercritical fluid (SCF) method to impregnate various Pd complexes into epoxy resin, and then decomposed them to produce free metal in the epoxy resin by reduction. An efficient electro-less Cu plating technique was achieved when the metal was deposited into the epoxy resin. This article describes the selection of the metal complexes, impregnation conditions of the complexes, and the peel strength of the plating.

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To preparing the printed circuit boards (PCB's) much more high speed processes are required keeping high quality of electrical properties. High reliability and guaranteed quality are also important. The latest PCB's are shifting into more fine line circuitry, high density and narrow space conductor lines. Recently, PCB's materials change from epoxy type to liquid crystalline polymer (LCP) type. An essential subject for this technology is to improve the weak copper adhesive peel strength on LCP insulation materials. To get the good adhesion property of copper plating, it is now widely applying Pd colloid solution method. To achieve more excellent adhesion for next decade generation PCB's, we are investigating supercritical fluid (SCF) method. In this paper, an attempt has been done to impregnate some metal complexes into LCP material and decomposed them to produce free metal in the resin by reduction. Using the deposited metal an efficient electro-less Cu plating is achieved. We will discuss on the selection of the metal complexes and impregnation condition of the complexes as well as peel strength of the plating.

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Two processes were tested for improving the washing and light fastness of cationic dyeing. The first method was to make pigments by intercalating the cationic dye into smectite and the second was post-treating the cationic dyed fabric with smectite. It was found that the coloration with pigments of dye-intercalated smectite was not as deep as dyeing cotton, silk and wool with a cationic dye, although the washing fastness was improved. Post-treating the cationic dyed cotton, silk and wool fabrics with smectite achieved a considerably deeper color and greatly improved the washing fastness. The depth of coloration of the post-treated fabrics depended on the particle diameter of the smectite used. The low light fastness of cationic dyed natural fibers could be considerably improved by intercalating the dye into smectite or post-treating the dyed fiber with smectite.

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