Patent ID: 7384902

Claim:
An alkaline brightening and cleaning composition for metal surfaces, the composition providing etching of aluminum without adversely effecting other, non-metallic surfaces, comprising: an alkali metal hydroxide having a concentration of substantially 1.6 to 16 g/l; a polycarboxylic acid having the formula (CH 2 CH 2 O) a N b (CH 2 ) c (CH 2 COOH) d , wherein a is from 0 to 1, b is from 1 to 3, c is from 0 to 4 and d is from 3 to 5 and having a concentration of substantially 0.9 to 9 g/l; an alkali metal salt of an organic acid selected from the group consisting of sodium gluconate and sodium glucoheptonate having a concentration of substantially 1.4 to 14 g/l; a first, amphoteric surfactant having a concentration of substantially 0.03 to 3 g/l; a second, betaine surfactant; a third, nonionic surfactant, the second betaine surfactant and the third nonionic surfactant having a combined concentration of substantially 0.1 to 1.8 g/l; and the balance being water, wherein the ratio of the alkali metal hydroxide or the alkali metal salt of an organic acid to the polycarboxylic acid is substantially from 0.6:1 to 6:1.