Etching glass with HF and fluorine-containing surfactant
AssigneeBayer Aktiengesellschaft
InventorsHans Niederprum, Heinz Gunter Klein, Johann-Nikolaus Meussdoerffer
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Abstract
In the etching of glass wherein glass is contacted with an aqueous etching bath containing hydrofluoric acid, and the glass is thereafter removed from the bath and rinsed, the improvement which comprises dissolving in the etching bath an acid-resistant wetting agent. Preferably the wetting agent contains fluorine, e.g. a perfluoralkane sulfonic acid quaternary ammonium salt, a perfluoralkane carboxylic acid salt, an alkoxylation product of a perfluoralkane sulfonamide, or the like.
Claims3
In the etching of glass wherein glass is contacted with an aqueous etching bath containing hydrofluoric acid, and the glass is thereafter removed from the bath and rinsed, the improvement which comprises dissolving in the etching bath an acid-resistant quaternary ammonium perfluoroalkane sulfonate wetting agent of the formula R.sub.F SO.sub.3 .sup.- NR.sup.1 R.sup.2 R.sup.3 R.sup.4 +, wherein R.sub.F is a linear or branched aliphatic perfluoroalkyl radical with from 6 to 12 carbon atoms, and R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each independently is an alkyl or aralkyl radical of up to 18 carbon atoms, or two or three of R.sup.1, R.sup.2 and R.sup.3 are attached to form a ring through the nitrogen atom.
An etching solution for treating glass, comprising water, hydrofluoric acid and an acid-resistant quaternary ammonium perfluoroalkane sulfonate wetting agent of the formula R.sub.F SO.sub.3 .sup.- NR.sup.1 R.sup.2 R.sup.3 R.sup.4 +, wherein R.sub.F is a linear or branched aliphatic perfluoralkyl radical with from 6 to 12 carbon atoms, and R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each independently is an alkyl or aralkyl radical of up to 18 carbon atoms, or two or three of R.sup.1, R.sup.2 and R.sup.3 are attached to form a ring through the nitrogen atom.
Dependencies are inferred from the claim text.