from 2 to 5 carbon atoms illustrative are monoethanolamine diethanolamine triethanolamine the mono di and tripropanolamines ethanolpropanolamine diethanolpropanolamine and the mono di and tributanolamines particularly preferred alkanolamines are those in which each alkanol group contains 2 3 carbon atoms such as the ethanolamines the propanolamines and the ethanolpropanolamines in a particularly preferred embodiment of the invention monoethanolamine is employed although the proportions of the ingredients may vary over wide ranges the etching solution preferably contains about 3 6 mole percent of the aromatic compound about 32 56 mole percent of the amine and about 65 38 mole percent of water more preferably the etching solution contains about 4 6 mole percent of the aromatic compound about 39 56 mole percent of the amine and about 57 38 mole percent of water various other ingredients may be added to the etching solution for example a small amount such as about 0 2 0 3 mole percent of pyrazine or piperidine or of hydrogen peroxide e g 0 5 3 ml 1000 ml of amine compound may be added in order to further enhance the etch rate of the solution in addition a small amount of a surfactant e g 0 5 3 ml 1000 ml of amine compound such as 34 fc 129 34 commercially available from minnesota mining amp manufacturing company or other fluorinated hydrocarbon surfactants may be added the presence of.