Abstract
An investigation was made of the relationship between paint adhesion and the various organic compounds coated on the surface of cold rolled steel, tin-free steel (T.F.S.), and electro galvanizedsteel. The effect of the number of double bounds in aliphatic acids, functional groups in aliphatic compounds and Inductive Effect of substituted groups in aromatic molecules were discussed on the basis of the results.
It was found that;
(1) Unsaturated linoleic acid (double bond =2) and linolenic acid (double bond =3) improve the paint adhesion, whereas saturated stearic acid and unsaturated oleic acid (double bond = 1) arerather harmful.
(2) Aliphatic molecules should have two functional groups to improve paint adhesion. -COOH and -NH2 are most desirable.
(3) Effect of aromatic compounds are largely influenced by absolute values of substituent constants (Hammett's σ value). This shows that Electron Inductive Effect must be considered in the case of aromatic molecules.
