Claims
- 1. A method for reducing the bleach catalyst carry-over from laundry bleach compositions containing manganese-containing bleach catalyst; said composition having less than about 40 ppm manganese sourced by the catalyst; said method comprising contacting fabrics impregnated with manganese-containing bleach catalysts with an aqueous solution having a pH below about 4.0.
- 2. The method according to claim 1 wherein the fabric impregnated with the bleach catalyst is contacted with the aqueous acidic solution for at least about 15 minutes.
- 3. The method according to claim 2 wherein the acidic solution comprises an acidifying agent selected from the group consisting of sulphamic acid, maleic acid, citric acid, polyacrylic acids, and mixtures thereof.
- 4. The method according to claim 1 wherein the fabric is impregnated with the bleach catalyst Mn.sup.IV.sub.2 (u-O).sub.3 (1,4,7-trimethyl-1,4,7-triazacyclononane).sub.2 (PF.sub.6).sub.2 or with its manganese decomposition by-products.
- 5. A method for reducing the carry-over of the metal sourced by the bleach catalyst from laundry bleach compositions containing the metal-containing bleach catalyst Mn.sup.IV.sub.2 (u-O).sub.3 (1,4,7-trimethyl-1,4,7-triazacyclononane).sub.2 (PF.sub.6).sub.2, said method comprising contacting fabrics impregnated with the metal-containing bleach catalyst Mn.sup.IV.sub.2 (u-O).sub.3 (1,4,7-trimethyl-1,4,7-triazacyclononane).sub.2 (PF.sub.6).sub.2 or manganese-containing decomposition products thereof with an aqueous acidic solution having a pH below about 4.0.
- 6. The method according to claim 5 wherein the fabric impregnated the the bleach catalyst is contacted with the aqueous acidic solution for at least about 15 minutes.
- 7. The method according to claim 6 wherein the acidic solution comprises an acidifying agent selected from the group consisting of sulphamic acid, maleic acid, citric acid, polyacrylic acids, and mixtures thereof.
- 8. The method according to claim 7 wherein the fabric is subsequently washed with an alkaline catalyst-free laundry detergent composition.
- 9. A method for bleaching fabrics, said method comprising the steps of:
- (a) washing one or more times fabrics in need of bleaching with laundry bleaching compositions comprising: (i) a peroxy compound present in an effective amount to cause bleaching; and (ii) less than about 40 ppm manganese sourced by the catalyst of a manganese-containing bleach catalyst present to activate the peroxy compound; followed by;
- (b) contacting the fabrics from step (a) with an aqueous solution having a pH below about 4.0; optionally followed thereafter by;
- (c) washing the fabric from step (b) in an alkaline, catalyst-free laundry detergent composition.
- 10. The method according to claim 9 wherein the manganese-containing bleach catalyst used in the composition for step (a) is the bleach catalyst Mn.sup.IV.sub.2 (u-O).sub.3 (1,4,7-trimethyl-1,4,7-triazacyclononane).sub.2 (PF.sub.6).sub.2.
Parent Case Info
This is a continuation-in-part application of application U.S. Ser. No. 08/224,385, fled Apr. 7, 1994, now abandoned.
US Referenced Citations (42)
Foreign Referenced Citations (1)
Number |
Date |
Country |
143491 |
Jun 1985 |
EPX |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
224385 |
Apr 1994 |
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