| abstract |
A method of making a metallic pattern on a substrate having a surface comprising bare metal in predetermined areas and metal coated by a resist in remaining areas comprisesn (i) protecting the bare metal by electrodepositing thereon a heat-curable polymeric film having (a) a group which is reactive with an isocyanate group and (b) a blocked isocyanate group, (ii) heating the electrodeposited polymeric film to render it resistant to a solvent with which the resist is removable, (iii) removing the resist from said remaining areas using a solvent which does not remove the electrodeposited polymeric film, thereby exposing metal in said remaining areas, and (iv) etching the metal exposed in step (iii) using an etchant which does not remove the electrodeposited polymeric film, thereby leaving a metallic pattern protected by the electrodeposited polymeric film, which can be removed subsequently using a solvent therefor. n The method is useful in the production of printed circuits. |