Coprecipitation of aluminum compounds with iron (III) compounds by sodium hydroxide was investigated, for the purpose of studying the preparation of pigments of iron oxide-aluminum oxide system by coprecipitation method. The results were summarized as follow : Aluminum compounds began to precipitate at about pH 4.0 by adding sodium hydroxide to the solution containing only aluminum ion, and this aluminum compounds precipitate dissolved over pH 10.0. On the other hand, amount of precipitated aluminum compounds increased by adding sodium hydroxide to the solu ion containing iron (III) and aluminum ions, remarkably so at pH 11.0. The mechanism of coprecipitation was much influenced by occlusion rather than by adsorption. Iron (III) or aluminum compounds precipitation from corresponding pure salt solution in the range of pH between acidic to neutral was found to be the amorphous basic sulfate. α-FeOOH was observed in such iron (III) precipitate at pH 12.0. However, α-Fe0OH was not recognized in coprecipitation products from (III) and aluminum solution at pH 12.0.
After the measurement of penetration rate of paraffin, alcohol, or acid homologue into glass powder bed by means of the improved penetration-rate-measurement apparatus, the mean capillary radius, contact angle, immersional tension, and adhesion energy of glass powder bed were calculated by the penetration rate equation derived from Poissieulle equation. As the results, the above four values obtained for each homologue were related to carbon number of hydrocarbon chain of liquid molecules. Thus, the following facts were concluded from the values of both immersional tension and adhesion energy. That is, the values became larger by increasing the carbon number of hydrocarbon chain in paraffin homhlogue and, on the contrary, the values decreased inversely in acid homologue. On the other hand, the values were approximately constant in alcohol homologue.
N-Substituted-3, 4-perylenedicarbonimides (N-R-PDCI) were synthesized by the condensation of sulfoperylene-3, 4-dicarboxylic anhydride (PDCA- S03H) with amines and the desulfonation of their products. Sulfoperylene-3, 4-dicarbonimide which was prepared by the sulfonation of 3, 4-perylenedicarbonimide with sulfuric acid was hydrolyzed with dilute potassium hydroxide solution to obtain PDCA-SO3H. By the condensation of PDCA-SO3H with amines (methylamine, ethylamine, monoethanolamine, aniline, p-toluidine and p-anisidine) the corresponding imide derivatives were obtained. Then the desulfonation of these imide derivatives in sulfuric acid solution gave the corresponding N-R-PDCI.