Rinse additive compositions providing glassware protection comprising insoluble zinc compounds
AssigneeThe Procter & Gamble Company
InventorsGregory S. Caravajal, Gretchen R. Hatfield
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Abstract
Disclosed are rinse additive compositions containing an insoluble inorganic zinc salt useful for inhibition of glassware corrosion caused by automatic dishwashing detergents in the dishwasher. These compositions are particularly desirable because use of them in the dishwasher does not result in precipitation of zinc insolubles on the dishware or dishwasher parts.
Claims15
A liquid rinse additive composition, for use in an automatic dishwashing machine to inhibit glassware corrosion caused by washing with an automatic dishwashing detergent composition, comprising:
- (a) from 0% to about 70% of a low-foaming polyoxyalkylene nonionic surfactant;
- (b) an amount of an insoluble inorganic zinc compound, having an average particle size of less than about 250 microns, that will provide the composition with a level of zinc of from about 0.01% to about 10.0%;
- and
- (c) from about 25% to about 90% of a solvent system.
A solid rinse additive composition for use in an automatic dishwashing machine to inhibit glassware corrosion caused by washing with an automatic dishwashing detergent composition comprising:
- (a) from 0% to about 70% of a low-foaming polyoxyalkylene nonionic surfactant;
- (b) an amount of an insoluble inorganic zinc compound, having an average particle size of less than 250 microns, that will provide the composition with a level of zinc of from about 1.0% to about 70%;
- and
- (c) from about 30% to about 98% of a binder.
A method of inhibiting corrosion of glassware caused by washing with an automatic dishwashing detergent composition, comprising adding to the rinse water an amount of an insoluble inorganic zinc compound which provides between 0.5 and 10 ppm solubilized zinc to the rinse water.
Dependencies are inferred from the claim text.