Lyophilic zinc powder has been prepared by reacting the zinc powder with n-butanol under the conditions of the high temperature and high pressure. By means of the microanalysis of the surface-treated zinc powder, observation through the electron microscope and dissolution into dil. HCl and also the fact that the surface-treated sample cannot be suspended into water, but into organic solvent, it was found that the only surface property of the powder was changed into the lyophilic, accompanying with no change of any fundamental property of the powder, e. g., surface area, pore structure or any chemical properties. This surface-treatment on the zinc powder was interpreted as the esterification of the acidic group of the surface oxide of the zinc powder with n-butanol. The zinc-rich paint from the surface-treated zinc powder shows the well-dispersed one into vehicle than from the untreated native zinc powder, whilst, the dry film of the paint prepared from the surface-treated zinc powder shows the easily breakable one than from the untreated native ones.
With regard to the methylated methylolmelamine produced by the reaction of methylolmelamine having different methylolation degree (tri-, tetra-, and hexa-methylolmelamine) with methanol catalyzed by an acid, the analyses of the functional groups, the solubility into various solvents, and the thermal property were investigated ; then its reaction mechanism was proposed. Next, the water soluble alkyd resin paint by the use of the methylated methylolmelamine as a cross-linking agent was investigated. As a main result, it was found that the increase of the viscosity decreases markebly, and the storage stability increases remarkably with increasing methylolation degree ; moreover, the effect of the solvents upon the increase of the viscosity, and the effect of the methylolation degree upon the hardness and flexibility after baking were tested.