Summer 1987
Electrolytic Photoetching and Its Applications
The technique of electrolytic photoetching involves production
of a resist stencil on a metal sheet by standard procedures
used in the photochemical (PCM) industry (1). However,
instead of spray-etching as in conventional PCM, metal
dissolution is achieved electrochemically by connecting the
metal sheet as an anode in an electrolytic cell.
Electrolytic photoetching for part production has probably
been developed from its use in the printing trade to surface-etch
printing plates. Such systems were reported in the 1920s for
etching copper and brass and over the next decade techniques
were refined and extended to include other materials such as
zinc and steel. Practical experimentation suggested that the
method offered distinct advantages (e.g. less undercut and a
faster rate of etching) over paddle-etching; its main rival at that
time (2).
Dr. D.M. Allen, Cranfield Institute of Technology
