Abstract An etchant liquid for metals (which consist mainly of aluminum) comprising an aqueous sulfuric acid solution containing halogen ions and the ions of a metal having an ionization tendency less than that of aluminum. An etching bath containing the above liquid also comprising a water-immiscible organic liquid, and a surface active agent prepared by the phosphoric esterification of a polyalkylene glycol having alkylene oxide linked with the hydrocarbon residual group thereof. A process for forming a photographic image of an acid-resistant coating applied to the surface of a metallic plate (which consists mainly of aluminum) which comprises etching the plate using the described etchant liquid or etching bath.
The etching process of claim 1 wherein the etchant liquid further comprises NO3 in an amount less than about 2 gram-ions/liter.
Claim 2
Dependent Claim
35 words
The etching process of claim 1 wherein said metal is an aluminum alloy consisting essentially of about 0.5 to about 10 percent by weight Zn and a small amount of impurities, the balance being aluminum.
Claim 3
Dependent Claim
44 words
The etching process of claim 1 wherein said metal is an aluminum alloy consisting essentially of about 0.5 to about 10 percent by weight Zn, about 0.04 to about 2.0 percent by weight Sn and a small amount of impurities, the balance being aluminum.
Claim 4
Dependent Claim
145 words
An etching process which comprises splashing an etching bath upon the surface of a metallic plate, said plate comprising a metal consisting essentially of aluminum and having thereon a photographic image of an acid-resistant coating, said etching bath comprising at least one halogen ion present in a concentration of from about 0.1 to about 7.0 grams-ions/liter, from about 0.004 to about 2.0 gram-ions/liter of the ions of a metal having an ionization tendency less than that of aluminum, from about 1 percent to about 10 percent by volume of a water-immiscible organic liquid, from about 0.05 percent to about 8 percent by weight of a surface active agent prepared by the phosphoric-esterification of a condensation-type nonionic surface active agent of an alkylene oxide and from about 3 percent to about 20 percent by weight sulfuric acid, the materials recited being present in an aqueous solution.
Claim 5
Dependent Claim
21 words
The etching process of claim 5 wherein said etching bath further comprises NO3 in an amount less than about 2 gram-ions/liter.
Claim 6
Dependent Claim
44 words
The etching process of claim 5 wherein said metal is an aluminum alloy consisting essentially of about 0.5 to about 10 percent by weight Zn, about 0.04 to about 2.0 percent by weight Sn and a small amount of impurities, the balance being aluminum.
Claim 7
Dependent Claim
35 words
The etching process of claim 5 wherein said metal is an aluminum alloy consisting essentially of about 0.5 to about 10 percent by weight Zn and a small amount of impurities, the balance being aluminum.