The coatings consisting with the vehicle of chlorinated rubber and rosin and the nutrients for shellfish, seaweed and plankton were formulated and applied on the test pannels of which the attachment and growth of shellfish and seaweed were expected after submersion in the sea. The effectiveness of the coatings was thus evaluated on the amount of attached shellfish and seaweed. As the nutrients, crab shell, gelatin, bean cake powder, cuppric oxide, urea, phosphatic manure, calcium phosphate, seaweed ash, fish meal, guanos, ammonium lignosulfonate and polymeric fertilizer such as the urealized chitosan, were employed. In any case, it was noted that the test panels incorporated with nutrient exhibited over twice more attached amount than the blank test panel did. Moreover, the color tone and hardness of coatings showed some effect to the amount of attachment, though it was only notable for earlier period of submersion. It was also investigated that the coatings incorporated with nutrients, and a pesticide which had selective toxicity against a particular living thing, such as 2, 4-dichlorophenoxy-acetic acid, prohibited seaweed from attachment, but only shell fish dominated on the panel.
A quantitative evaluation method of fabricability of cured enamel on the substrate in deep drawn cylindrical cup fabrication was proposed. In case of deep drawn cylindrical cup fabrication, compressive force acts in the circum-ferential direction and tensile force acts in the radial direction to the original sheet of fabrication. If the coated film on the substrate can not stand these forces, the film will fail. By determining the strain where the film failure arised, the fabricability of the coated film was evaluated. As the result, coated films were considered to be more vulnerable to compressive force than tensile force. The relationships between formulation of phenolic-epoxy enamels, curing schedule, kinds of substrate and fabricability for these enamels were also discussed.