The measurement of leveling of bright copper plating from both low and high concentration baths such as CuSO₄⋅5H₂O 100g/l, H₂SO₄ 150g/l and CuSO₄⋅5H₂O 200g/l, H₂SO₄ 50g/l was carried by using Hull Cell test panel. Leveling of bright copper plating from the low concentration bath was found to be less than that from the high concentration bath at the high current density, however, low concentration bath gave the better leveling in the low current density region, and at high temperatures such as above 30°C. The brightener for copper sulfate bath was composed of thiourea derivative, dyestuffs and wetting agents. Neither the levering nor the bright copper plating was obtained from the bath in which each one or two components of the brightener were added. However, when three components of the bringhtener were used together in the bath, copper plating gave good leveling and brightness. The optimum concentration of these compoents for the low concentration copper sulfate bath was as follows; thiourea derivative (1% solution) 2-3ml/l, dyestuffs (1% solution) 0.25-0.5ml/l, and wetting agents (low polymer 1%, high polymer 0.1% solution) 1ml/l.

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In vacuum evaporation of metals, the temperature rise on the substrate surface due to the heat of evaporation is of importance, especially for the materials that are subject to low temperature thermal deformation and also frozen substrates. The present experiment concerns the reflection and absorption of radiation by the evaporated thin films, their influences on the surface temperature rise and differences in the temperature rise of the substrates due to the kinds of evaporated materials, evaporation rates etc. Characteristics of the heat of evaporation and basic conditions for reducing the temperature rise caused by the heat of evaporation are discussed. The results indicate that the absorption and reflection of radiation by the evaporated thin films, different from those by block materials, vary to a great extent with the film thicknesses. For the film thicknesses more than 700Å, inherent values depending on the kinds of evaporated materials were obtained; however, the absorption and refelction affect the temperature rise to a lesser extent. This would be interpreted that the temperature rise due to the kinetic and condensation energies are greater than those by radiation. The temperature rises on the substrates vary with the kinds of evaporated substances and evaporation rates; the rises are greater for C, Cr, and Si but lesser for Cu and Ge. For a constant thickness of an evaporated film, the temperature rise is reduced with greater deposition rate and shorter deposition time.

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Titanium specimens covered with teflon sheets were electrochemically polarized in 3M NaCl solution at 25°C and the pH of the solution in a crevice was measured by using a pH-sensitive glass microelectrode whose tip was about 30 microns in outer diameter. It was found that the pH in the crevice decreases gradually and then steeply as the anodic polarization is increased. The pH was found to increase gradually with increasing cathodic polarization. The effect of surface preparation, such as mechanical polishing and chemical polishing, on the pH change was explained in terms of the electrochemical reactions occurring in the crevice.

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Opaque oxide films from greyish white to milky white in color were obtained when Al-Mg-Si alloy sheets having been anodized at constant voltages (80 and 90V) in 2.5W/V% oxalic acid-7.5W/V% phosphoric acid mixed solution, were reanodized at constant voltages (10, 12.5 and 15V) in 15W/V% sulfuric acid solution. When the mixed acid oxide films were reanodized in sulfuric acid solution, the current of secondary anodizing recovered gradually as the reanodizing time elapsed. The cell structures of mixed acid oxide films changed as the current recovered, thus the colored opaque oxide films were obtained.

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Anodic oxide films on aluminum formed in a sulfuric acid bath are cathodically polarized in a mixed solution of nickel sulfate with boric acid by the potential sweep method. Three peaks of cathodic current are observed on the voltammograms. The peak current at -4 (V) is due to reduction of H⁺ ions, and the cause of the peak current at -13 (V) is unknown. The peak current at -18 (V) is due to reduction of Ni²⁺ ions.

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