Anti-tarnish aqueous treatment

Abstract

An aqueous solution that has the capacity for removing tarnish and other soil from copper, silver, gold and other noble metals and alloys thereof comprises an acid, thiourea and a transition metal salt. The aqueous material can be used to treat the surfaces of such articles for the purpose of removing tarnish. Such tarnish is removed by the composition and the composition treats the metal surface to retard the re-appearance of tarnish contaminants.

Description

FIELD OF THE INVENTION [0001] The invention relates to an aqueous solution comprising a combination of soluble ingredients forming a product having tarnish removing and tarnish preventing properties. The invention also relates to a method of cleaning and preserving metal surfaces subject to tarnish formation and formation of similar soil deposits. BACKGROUND OF THE INVENTION [0002] Many high value products made from copper, silver, gold, other noble metals and alloys thereof can be subject to soiling, dulling or tarnish formation due to atmospheric contaminants, environmental conditions or by handling and use. These metal objects can often form surface deposits of one or more metal oxides or metal sulfides that can be difficult to remove without reducing the appearance, quality or purity of the metal surface. Many mechanical cleaning methods cause scratching or marring of the surface. Chemical cleaners can visually change surface appearance. Cleaners and polishers are available, but...

AI Technical Summary

Problems solved by technology

Many high value products made from copper, silver, gold, other noble metals and alloys thereof can be subject to soiling, dulling or tarnish formation due to atmospheric contaminants, environmental conditions or by handling and use.

These metal objects can often form surface deposits of one or more metal oxides or metal sulfides that can be difficult to remove without reducing the appearance, quality or purity of the metal surface.

Many mechanical cleaning methods cause scratching or marring of the surface.

Cleaners and polishers are available, but involve substantial time and effort in application, are often difficult to use, tend to clean unevenly and fail often to remove all tarnish or prevent the reformation of an undesirable deposit on the surface.

Many of the materials, however, do not adequately perform the combination of roles by both removing tarnish and, at the same time, preventing tarnish return.