Electroless-plating technique

Palladium and palladium-silver alloy membranes on porous alumina tubes were prepared by means of simultaneous and sequential electroless plating techniques [234], The membrane reactor was used for the direct formation of hydrogen peroxide by catalytic reaction of H2 and 02 at 293 K. The concentration of H202 increased with increases in the transmembrane partial pressure gradient of H2. A high concentration of H202 was obtained with a membrane that consisted of a palladium layer on the outer surface, porous alumina in the middle, and a palladium-silver alloy layer on the inside. 

Ozaki, T, Zhang, Y, Komaki, M, Nishimura, C. Preparation of paUadium-coated V and V-15Ni membranes for hydrogen purification by electroless plating technique. Int J Hydrogen Energy. 2002 28 297-302. 

Yeung KL, Christiansen SC, Varma A. Palladium composite membranes by electroless plating technique relationships between plating kinetics, film micro structure and membrane performance. J Memb Sci. 1999 159(1-2) 107. 

K. Kuraoka, H. Zhao, T. Yazawa, Pore-filled palladium-glass composite membranes for hydrogen separation by novel electroless plating technique, J. Mater. Sci. 2004, 39, 1879-1881. 

In one electroless plating technique, which reportedly achieves attenuation levels of 70 dB in layers of 1-2 microns thick, the molded part is immersed in an aqueous solution of copper salt, reducing agent, and initiator to obtain copper deposition as the primary shielding layer. Nickel is then added to form an outer layer that provides corrosion resistance and improved impact strength. 

The membranes are produced in a three-step procedure at first, Pd is deposited onto the AI2O3 support by electroless plating technique, and then Ag is layered on by electroplating using the Pd layer as electrode. The layered Pd-Ag membrane is finally heat-treated to obtain the Pd-Ag alloy membrane. 

Articles formed from mineral-filled PPA resins can be metallized by electroless and electroplating techniques [64]. Special formulations of PPA can be metallized by the same electroless plating techniques developed for ABS resins. Those techniques consist of ... 

By the laser treatment, the surface of PTFE films could be made hydrophilic and the surface energy increased in comparison with that of a native PTFE film. As the results, we intended to extend the hydrophilic modification technique into metallization on the PTFE film by using a chemical (electroless) plating technique. If the activators for the plating will deposit only on the hydrophilic region, area-selective metallization will be performed on the surface of PTTE films modified upon the laser-irradiation through a mask by a projection method. 

Copper and nickel were successfully coated using electroless plating techniques to give excellent penetration of the tows with a uniform deposit, but the method proved to be too expensive. 

Morgan undertook evaluation of carbon fibers produced in Courtauld s research laboratories. He established procedures to coat carbon fibers with metals using electroless plating techniques and developed a surface treatment process to improve the bond of carbon fibers to epoxy resins. 

Protective Chip Pad Layer. As with virtually all flip chip processes, the A1 bond pads must be protected to eliminate the formation of nonconductive aluminum oxide. This ensures a low and stable resistance at bond-bond pad interface. The PFC process utilizes an electroless plating technique, using Ni/Au or Pd, to cover the A1 bond pads prior to polymer bumping. The typical metal thickness is 0.5-1.0 pm for Pd and 3.0-5.0 pm for Ni/Au. 

Cheng, Y.S. Yeung, K.L. (1999). Palladium-silver comp>osite membranes by electroless plating technique. Journal of Membrane Science Vol.158, pp. 127-141. 

The Electroless Plating technique (EPD) [5] was used to obtain dense Pd layers on various PSS substrates. From the characterization results obtained for modified PSS supports, two of them were set as substrates for the synthesis of Pd composite membranes by EPD. The first support was obtained after oxidation at 700°C for 12h and the second one was obtained by coating a thin layer of Zr02. The PSS substrates were activated prior to Pd deposition. The activation process was performed using sequential dipping in SnCl2-HCl (1 g/1, pH 2) and PdC -HCl (0.1 g/1, pH 2) solutions. 

Bottino A., CapanneUi G., Comite A., Di Eelice R., Brogha M. and Pinacci P, Pd and Pd/Ag composite membranes prepared by the electroless plating technique preparation, characterization and interpretation of the Hj transport mechanism, Proc. ofICIM 9, LiUehammer (NO), June 25-29,2006. 

Cheng Y. S. and Yeung K. L., Palladium-silver composite membranes by electroless plating technique,/ Membrane Sci., 158 (1999) 127-141. 

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