Claims
- 1. An automatic dishwashing detergent composition comprising:
- a) 1 to 20 weight percent of a bleaching agent selected from the group of a peroxygen agent, a hypohalite agent and its corresponding salts, and mixtures thereof;
- b) 0.05 to about 10 weight percent of a 1,3-N azole compound which prevents silver tarnishing having a formula: ##STR14## wherein X is C--R.sub.3 or X is nitrogen if, and only if Y is nitrogen, Y is nitrogen or C--R.sub.2, and R.sub.1, R.sub.2, and R.sub.3 are each independently a hydrogen, an amine, an amido, a straight or branched alkyl chain having from 1 to 20 carbon atoms, an amino or carboxylic containing chain, an alkoxy, an alkylthio, a hydroxy, a hydroxyalkyl, and an alkenyl, or R.sub.1 and R.sub.2 taken together form a substituted or unsubstituted aryl and salts corresponding thereto
- provided that the 1,3-N azole compound has a pK.sub.a value of more than 1 unit below a pH value of an aqueous solution of an automatic dishwashing detergent composition in which it is incorporated;
- c) 1 to 75 weight percent of a builder; and
- d) 0 to 40 weight percent of a surfactant,
- wherein the automatic dishwashing composition substantially prevents tarnishing of silver and silver plated articles and the composition has a pH in a range of about 7 to about 8.8.
- 2. A detergent composition according to claim 1 wherein the anti-tarnishing compound of formula I is a compound wherein X is nitrogen provided Y is nitrogen or X is CR.sub.3, Y is C--R.sub.2 and R.sub.1, R.sub.2 and R.sub.3 are each independently having 1 to 6 carbons, an amine branched alkyl chain and an amino or carboxylic containing moiety or R.sub.1 and R.sub.2 taken together form the substituted or unsubstituted aryl.
- 3. A detergent composition according to claim 1 wherein the anti-tarnishing compound of formula I is a compound wherein the substituted or unsubstituted aryl contains a N or an O.
- 4. A detergent composition according to claim 1 wherein the anti-tarnishing compound of formula I is selected from the group consisting of imidazole, benzimidazole, and 1,2,4-triazole, 5-aminotetrazole, 3-amino 1,2,4-triazole and histidine.
- 5. A detergent composition according to claim 1 wherein the peroxygen agent is an organic agent or an inorganic agent.
- 6. A detergent composition according to the claim 5 wherein the organic agent is selected from the group consisting of epsilon-phthalimido peroxyhexanoic acid, o-carboxybenzamidoperoxyhexanoic acid and N,N-terephthaloyldi(6-aminopercaproic acid).
- 7. A detergent composition according to claim 5 wherein the inorganic agent is selected from a group consisting of salts of monopersulfate, perborate monohydrate, perborate tetrahydrate, percarbonate and mixtures thereof.
- 8. A detergent composition according to claim 1 further comprising an effective amount of a peracid precursor.
- 9. A detergent composition according to claim 8 wherein the peroxygen peracid precursor is selected from a group consisting of sodium p-benzoyloxybenzene sulfonate, N,N,N',N'-tetraacetylethylenediamine, sodium nonanoyloxybenzene sulfonate and choline sulfophenyl carbonate.
- 10. A detergent composition according to claim 1 wherein the hypohalite agent is sodium hypochlorite.
- 11. A detergent composition according to claim 1 wherein the builder is selected from the group consisting of alkali metal citrates, succinates, aluminosilicates, polycarboxylates, tartrate disuccinates and mixtures thereof.
- 12. A detergent composition according to claim 1 wherein the anti-tarnishing compound is present in an amount of from about 0.25 to about 2.5 weight percent.
- 13. A detergent composition according to claim 1 further comprising about 0.1 to 40 weight percent of an alkalinity agent.
- 14. A detergent composition according to claim 1 further comprising an enzyme in an amount of up to about 10 weight percent.
- 15. A detergent composition according to claim 1 wherein the pK.sub.a value of the 1,3-N azole compound is more than 1 unit and up to 6 units below the pH value of the aqueous solution of the composition.
- 16. A method for substantially preventing tarnishing of silver or silver plated articles in an automatic dishwashing machine comprising the steps of:
- washing silver or silver plated articles in an effective amount of a detergent composition having a pH of about 7 to 8.8 comprising:
- i) 1 to 20 weight percent of a bleaching agent selected from the group of a peroxygen agent, a hypohalite agent and its corresponding salts, and mixtures thereof;
- ii) 0.05 to about 10 weight percent 1,3-N azole compound which prevents silver tarnishing having a formula: ##STR15## wherein X is C--R.sub.3 or X is nitrogen if, and only if Y is nitrogen, Y is nitrogen or C--R.sub.2, and R.sub.1, R.sub.2, and R.sub.3 are each independently a hydrogen, an amine, an amido, a straight or branched alkyl chain having from 1 to 20 carbon atoms, an amino or carboxylic containing chain, an alkoxy, an alkylthio, a hydroxy, a hydroxyalkyl, and an alkenyl, or R.sub.1 and R.sub.2 taken together form a substituted or unsubstituted aryl and salts corresponding thereto provided that the 1,3-N azole compound has a pK, value of more than 1 unit below the pH value of an aqueous solution of an automatic dishwashing detergent composition in which it is incorporated;
- iii) 1 to 75 weight percent of a builder; and
- iv) 0 to 40 weight percent of a surfactant, to substantially prevent tarnishing of the silver or silver-plated articles.
- 17. A method according to claim 16 wherein the anti-tarnishing compound of formula I is a compound wherein X is nitrogen provided Y is nitrogen or X is CR.sub.3, Y is C--R.sub.2 and R.sub.1, R.sub.2 and R.sub.3 are each independently having 1 to 6 carbons, an amine branched alkyl chain and an amino or carboxylic containing moiety or R.sub.1 and R.sub.2 taken together form the substituted or unsubstituted aryl.
- 18. A method according to claim 17 wherein the anti-tarnishing compound of formula I is a compound wherein the substituted or unsubstituted aryl contains a N or an O.
- 19. A method according to claim 16 wherein the anti-tarnishing compound of formula I is selected from the group consisting of imidazole, benzimidazole, and 1,2,4-triazole, 5-aminotetrazole, 3-amino 1,2,4-triazole and histidine.
- 20. A method according to claim 16 wherein the pK.sub.a value of the 1,3-N azole compound is more than 1 unit and up to 6 units below the pH value of the aqueous solution of the composition.
RELATED APPLICATIONS
This application is a continuation-in-part of U.S. Ser. No. 08/136,791, filed Oct. 14, 1993, abandoned.
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Continuation in Parts (1)
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Number |
Date |
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Parent |
136791 |
Oct 1993 |
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