Automatic dishwashing compositions comprising cobalt catalysts
US5705464A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 6, 1997 |
| Grant date | Jan 6, 1998 |
| Priority date | — |
| Expiry date | Feb 6, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC11D3/3932
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
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 bleach catalyst having the formula: EQU Co(NH.sub.3).sub.n (M).sub.m (B).sub.b !T.sub.y wherein cobalt is in the +3 oxidation state; n is 4 or 5 (preferably 5); M is one or more ligands coordinated to the cobalt by one site; m is 0, 1 or 2 (preferably 1); B is a ligand coordinated to the cobalt by two sites; b is 0 or 1 (preferably 0), and when b=0, then m+n=6, and when b=l, then m=0 and n=4; and T is one or more appropriately selected counteranions present in a number y, where y is an integer to obtain a charge-balanced salt (preferably y is 1 to 3; most preferably 2 when T is a -1 charged anion); and wherein further said catalyst has a base hydrolysis rate constant of less than 0.23 M.sup.-1 s.sup.-1 (25.degree. C.). Preferred automatic dishwashing compositions comprise amylase and/or protease enzymes. Included are methods for washing tableware in domestic automatic dishwashing appliances using the …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.