Patent ID: 7638473

Claim:
A method for using a warewashing detergent composition, the method comprising: (a) diluting a solid warewashing detergent composition with water at a dilution ratio of water to warewashing detergent composition of at least about 20:1 to form a warewashing detergent use composition, wherein the warewashing detergent use composition comprises: (i) a cleaning agent comprising a detersive amount of a surfactant; (ii) an alkaline source in an amount effective to provide the use composition with a pH of at least about 8, wherein the alkaline source comprises at least one of sodium hydroxide, potassium hydroxide, or mixtures thereof; and (iii) between about 6 ppm and about 300 ppm of a corrosion inhibitor for reducing corrosion of glass, the corrosion inhibitor comprising a source of zinc ion and a source of aluminum ion in amounts sufficient to provide the use composition comprising zinc ion and aluminum ion at a weight ratio of zinc ion to aluminum ion of at least about 2:1; and (b) washing ware with the use composition in an automatic dishwashing machine.