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US 6,551,977 B2Granted
Air bleaching catalysts with enhancer and moderating agent
AssigneeUnilever Home & Personal Care USA, Division of Conopco, Inc.
InventorsRonald Hage, Roelant Mathijs Hermant, Simon Marinus Veerman
Life of this patent
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Abstract
The invention relates to catalytically bleaching substrates, especially laundry fabrics, with a bleaching catalyst in the presence of an unsaturated organic compound and an activity moderator.
Claims22
A bleaching composition comprising an organic ligand which forms a complex with a transition metal for bleaching a substrate with a group selected from:
- a) atmospheric oxygen, the bleaching composition upon addition to an aqueous medium providing an aqueous bleaching medium substantially devoid of a peroxygen bleach or a peroxy-based or peroxyl-generating bleach system;
- and,
- b) a peroxygen bleach or source thereof,
- together with a surfactant having an allylic hydrogen, said surfactant having an HLB of greater than 2, and at least two antioxidants, whereby the combination of the at least two antioxidants provides in a solution containing oleic acid an effective reduction in the formation of hexanal from the oleic acid under ambient atmospheric conditions by a factor of at least three in comparison with same bleaching composition having a molar equivalent of a single antioxidant equivalent to the combined molar concentration of the at least two antioxidants, said single antioxidant being one of the at least two antioxidants.
1 more element
A bleaching composition for bleaching a substrate, the bleaching composition comprising:
- (i) an organic ligand which forms a complex with a transition metal for bleaching with oxygen sourced from the air;
- (ii) 0.01 to 60 wt/wt % of a surfactant having an HLB of greater than 15, the surfactant a sodium salt of an unsaturated carboxylic acid having an allylic hydrogen;
- and,
- (iii) 0.001 to 5% wt/wt % of at least two antioxidants in a molar ratio of at least 5%,
- said bleaching composition comprising less than 2% mMol of peroxide per Kg, wherein upon addition of the bleaching composition to an aqueous solution and in the presence of the substrate and least 10% of any bleaching of the substrate is effected by oxygen sourced from the air and wherein the combination of the at least two antioxidants provides in a solution containing oleic acid an effective reduction in the formation of hexanal from the oleic acid under ambient atmospheric conditions by a factor of at least three in comparison with same bleaching composition having a molar equivalent of a single antioxidant equivalent to the combined molar concentration of the at least two antioxidants, said single antioxidant being one of the at least two antioxidants.
2 more elements
Dependencies are inferred from the claim text.