Abstract: An alkaline, aqueous cleaning solution which is capable of removing at least a substantial portion of uncured adhesive residues, e.g., epoxy-based adhesives, from a substrate, preferably a metal stencil substrate, contains water, an alkalinity-providing agent and a synergistic combination of surfactants, specifically an N-alkylpyrrolidone surfactant, which is preferably N-octyl-2-pyrrolidone, and an aminocarboxylic acid surfactant, which is preferably N-coco-beta-aminopropionic acid. At an active-concentration ratio of the N-alkyl-2-pyrrolidone surfactant to the aminocarboxylic acid surfactant of from about 1:1 to about 3.5:1 and a total active concentration of at least 0.30% by weight of the aqueous cleaning solution, the N-alkyl-2-pyrrolidone and aminocarboxylic acid surfactants synergistically improve the ability of the solution to remove uncured adhesive residues from the substrate, even at relatively low wash temperatures, e.g., from about 70.degree. F. to less than about 135.degree. F.

Abstract: An alkaline aqueous cleaning composition for cleaning a substrate, e.g., a plastic or metal substrate, contaminated with industrial-type soil contaminants contains (i) an aqueous portion and (ii) an active-ingredient portion composed of (A) an alkalinity-providing agent and (B) a surfactant mixture containing (a) an active concentration of an N-octyl-2-pyrrolidone surfactant and (b) an active concentration of at least one aminocarboxylic acid surfactant. The active-concentration ratio of surfactant (a) to surfactant (b) is such as to provide the cleaning composition with the ability to remove a substantial portion of the contaminants from the substrate. At an active-concentration ratio of surfactant (a) to surfactant (b) of about 2.5:1, the surfactants have a synergistic effect on the industrial-soil-removing ability of the aqueous composition.