Aqueous electronic circuit assembly cleaner and method
AssigneeChurch & Dwight Co., Inc.
InventorsAnthony E. Winston, Francis R. Cala, Alfredo Vinci, M. Stephen LaJoie
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Abstract
The present invention relates to environmentally safe aqueous cleaning compositions for cleaning electronic circuit assemblies, such as printed circuit or printed wiring boards, during their fabrication. Alkali metal carbonate and bicarbonate salts are utilized with an alkali metal silicate to achieve a variety of objectives, among which are the removal of solder flux, oils, waxes, and greasy substances, adhesives and other residues as well as provide anti-corrosion protection and metal brightening.
Claims16
A cleaning composition comprising (a) alkali-metal carbonate, or mixtures of alkali metal carbonate and bicarbonate salts, (b) an alkali metal silicate, (c) an antifoam agent, a surfactant or both and (d) sodium octanoate or sodium nonanoate, wherein (a), (b), (c) and (d) are so combined that when in an aqueous cleaning solution at a concentration of from about 0.6 to 15 percent by weight said solution has a pH of from about 10 to 13.
An aqueous concentrated solution comprising from about 5 to 45 percent by weight of a cleaning composition, said cleaning composition comprising (a) alkali-metal carbonate, or mixtures of alkali metal carbonate and bicarbonate salts, (b) an alkali metal silicate, (c) an antifoam agent, a surfactant or both and (d) sodium octonoate or sodium nonanoate, wherein (a), (b) (c) and (d) are so combined that when in an aqueous cleaning solution at a concentration of from about 0.6 to 15 percent by weight said solution has a pH of from about 10 to 13.
An aqueous cleaning solution comprising from about 0.6 to 15 percent by weight of a cleaning composition, said cleaning composition comprising (a) alkali-metal carbonate, or mixtures of alkali metal carbonate and bicarbonate salts, (b) an alkali metal silicate, (c) antifoam agent, surfactant or both, and (d) sodium octonoate or sodium nonanoate, wherein, (a) (b), (c) and (d) are so combined that said solution has a pH of from about 10 to 13.
Dependencies are inferred from the claim text.