Automatic dishwashing compositions comprising cobalt chelated catalysts

• US 6,020,294 A
• Filed: 05/28/1999
• Issued: 02/01/2000
• Est. Priority Date: 02/02/1995
• Status: Expired due to Term

• Current Assignee: The Procter & Gamble Company
• Original Assignee: The Procter & Gamble Company
• Inventors: Goldstein, Alan Scott, Getty, Edward Eugene, Scheper, William Michael
• Primary Examiner(s): Gupta, Yogendra
• Assistant Examiner(s): DelCotto, Gregory R.
• Application Number:
  US09/322,959
• Time in Patent Office: 249 Days
• Field of Search: 510/220, 510/221, 510/224, 510/372, 510/376, 556/148, 556/149
• US Class Current: 510/220
• CPC Class Codes: C11D 2111/14 Hard surfaces
• CPC Class Codes: C11D 3/3932 Inorganic compounds or complexes
• CPC Class Codes: C11D 3/3947 Liquid compositions

Abstract

Automatic dishwashing detergent compositions comprising certain cobalt catalysts are provided. More specifically, the invention relates to automatic dishwashing detergents which provide enhanced cleaning/bleaching benefits (especially tea stain removal) through the selection of cobalt chelated catalysts having the formula:

[Co.sub.n L.sub.m X.sub.p ].sup.z Y.sub.z.

Preferred automatic dishwashing compositions comprise amylase and/or protease enzymes. Included are methods for washing tableware in domestic automatic dishwashing appliances using the cobalt catalysts.

Claims

1. A method of bleaching a substrate, said method comprising applying an aqueous solution of a composition, to said substrate said composition comprising a catalytically effective amount of an cobalt catalyst having the formula:

space="preserve" listing-type="equation">[Co(NH.sub.3).sub.5 OAc]T.sub.y

wherein T is one or more counteranions present in number y, wherein y is 1 or 2; and

a source of hydrogen peroxide.

2. A method according to claim 1 wherein T is selected from the group consisting of Cl^-, Br^-, I^-, F^-, I₃^-, CH₃ COO^-, formate, nitrate, nitrite, sulfate, sulfite, citrate, carbonate, PF₆^-, BF₄^-, B(Ph)₄^-, phosphate, phosphite, silicate, tosylate, methanesulfonate, and mixtures thereof.

3. A method according to claim 2 wherein said aqueous solution is an aqueous alkaline bath.

4. A method according to claim 1 wherein the pH of said solution is below 11.

5. A method according to claim 1 wherein said composition comprises from about 0.1% to about 70%, of said hydrogen peroxide source;

and from about 0.01% to about 2%, of said catalyst.

6. A method according to claim 1 wherein T is Cl^-.