Patent ID: 8293696

Claim:
A composition comprising: water; an alkali metal hydroxide component in an amount of at least 30% by weight of the composition; about 0.5% to about 8% by weight of the composition of a chelating component selected from the group consisting of an EDTA component, a polyacrylate component, a NTA component and mixtures thereof; and about 0.01 to about 2.5% by weight of the composition of a HEIDA component effective to increase the solubility of the chelating component in the composition relative to an identical composition without the HEIDA component including an insoluble amount of the chelating component, the composition being in the form of a liquid solution and, after being stored for 4 weeks at room temperature and quiescent conditions, forms substantially no solid precipitate, and the weight ratio of the chelating component to the HEIDA component is greater than one.