Enhancement of air bleaching catalysts

Cleaning compositions for solid surfaces – auxiliary compositions – Cleaning compositions or processes of preparing – With oxygen or halogen containing chemical bleach or oxidant...

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C510S375000, C510S399000

Reexamination Certificate

active

06518231

ABSTRACT:

FIELD OF INVENTION
This invention relates to the enhancement of air bleaching catalysts in laundry.
BACKGROUND OF INVENTION
The use of bleaching catalysts for stain removal has been developed over recent years. The recent discovery that some catalysts are capable of bleaching effectively in the absence of an added peroxyl source has recently become the focus of some interest, for example: WO9965905; WO0012667; WO0012808; WO0029537, and, WO0060045.
Ways of enhancing the activity or improving the stain bleaching profile of these catalysts are desired.
SUMARY OF INVENTION
We have found that the presence of an organic substance having an allylic hydrogen enhances the effectiveness of an air bleaching catalyst in use. The organic substance is provided in a bleaching composition as either an ionic unsaturated surfactant and/or unsaturated non-ionic surfactant.
The present invention provides a bleaching composition comprising an organic substance which forms a complex with a transition metal for bleaching a substrate with 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, said composition comprising a surfactant having an allylic hydrogen and an HLB of greater than 2.
The surfactant having an allylic hydrogen has an HLB (hydrophilic/lipophilic balance) greater that 2, more preferably greater than 5, and most preferably greater than 10. For a discussion of HLB the reader is directed to and article by Griffin, W. C. in J. Soc. Cosmetic Chemists Vol. 1 page 311, 1945 and Davies, J. T. and Rideal, E. K. in Interfacial Phenomena, Acad. Press, NY, 1961, pages 371 to 382. The HLB value requirement reflects the importance of the rate of solubility and dispersibility of the surfactant having an allylic hydrogen from the bleaching composition to the aqueous wash medium in conjunction with surface activity towards the substrate being washed. The threshold value of HLB as required excludes compounds that have an allylic which do not have the required surfactant properties, for example linoleaic or oleic acid have an HLB of 0.8.
It is preferred that the surfactant having an allylic hydrogen has a CMC of 2×10
−2
M or less. It is most preferred that the surfactant is anionic has a critical micelle concentration value of 3×10
−3
M or less. Generally, a surfactant will form a micelle when present in an aqueous solution above a specific concentration that is intrinsic to the surfactant. A micelle is a neutral or electrically charged colloidal particle, consisting of oriented molecules. Above what is known as the critical micelle concentration CMC amphiphilic compounds tend to adopt specific aggregates in aqueous solution. The tendency is to avoid contact between their hydrophobic alkyl chains and the aqueous environment and to form an internal hydrophobic phase. Such compounds can form monomolecular layers [monolayers] at the air-water boundary and bimolecular layers [bilayers] between two aqueous compartments. Micelles are spherically closed monolayers.
The property required is that the surfactant used in the present invention is and forms a micelle at a concentration of 2×10
−2
M and below in an aqueous solution at a temperature of 25° C. One skilled in the art will be aware that the standard CMC is measured in deionized water and that the presence of other components in solution, e.g. surfactants or ions in solution will perturb the CMC value. The CMC values and requirement thereof as described herein are measured under standard conditions (N. M. Van Os, J. R. Haak, and L. A. M Rupert, Pysico Chemical Properties of Selected Anionic Cationic and Nonionic Surfactants Elsevier 1993; Kresheck, G. C. Surfactants-In water a comparative treatise- (ed. F. Franks) Chapter 2 pp 95-197 Plenum Press 1971, New York; and, Mukerjee, P. and Mysels K. J. Critical Micelle Concentrations of Aqueous Surfactant Systems, NSRDS-NBS 36, National Bureau of Standards. US Gov. Print office 1971, Washington, D.C.).
The term “substantially devoid of a peroxygen bleach or a peroxy-based or peroxyl-generating bleach system” should be construed within spirit of the invention. It is preferred that the composition has as low a content of peroxyl species present as possible. Nevertheless, autoxidation is something that is very difficult to avoid and as a result small levels of peroxyl species may be present. These small levels may be as high as 2%. The additionally added organic compounds having labile CH's are particularly susceptible to autoxidation and hence may contribute more to this level of peroxyl species than other components. However the presence of an antioxidant in the composition will serve to reduce the presence of adventitious peroxyl species. The composition of the present invention bleaches a substrate with at least 10%, preferably at least 50% and optimally at least 90% of any bleaching of the substrate being effected by oxygen sourced from the air.
The present invention extends to a method of bleaching a substrate comprising applying to the substrate, in an aqueous medium, the bleaching composition according to the present invention.
The present invention extends to a commercial package comprising the bleaching composition according to the present invention together with instructions for its use.
The bleaching composition may be contacted to the textile fabric in any suitable manner. For example, it may be applied in dry form, such as in powder form, or in a liquor that is then dried, for example as an aqueous spray-on fabric treatment fluid or a wash liquor for laundry cleaning, or a non-aqueous dry cleaning fluid or spray-on aerosol fluid.
Any suitable textile that is susceptible to bleaching or one that one might wish to subject to bleaching may be used. Preferably the textile is a laundry fabric or garment.
In a preferred embodiment, the method according to the present invention is carried out on a laundry fabric using an aqueous treatment liquor. In particular, the treatment may be effected in a wash cycle for cleaning laundry. More preferably, the treatment is carried out in an aqueous detergent bleach wash liquid.
In a preferred embodiment, the treated textile is dried, by allowing it to dry under ambient temperature or at elevated temperatures. The elevated temperatures are commonly provided by a heated agitated environment, as for example found in a tumble dryer, which has been found to accelerate and enhance the air bleaching effect. The effect of ironing the treated textile also serves to accelerate bleaching.
The bleaching method may be carried out by simply leaving the substrate in contact with the bleaching composition for a sufficient period of time. Preferably, however, the bleaching composition is in an aqueous medium, and the aqueous medium on or containing the substrate is agitated.
The bleaching composition may be contacted with the textile fabric in any conventional manner. For example it may be applied in dry form, such as in powder form, or in a liquor that is then dried, for example in an aqueous spray-on fabric treatment fluid or a wash liquor for laundry cleaning, or a non-aqueous dry cleaning fluid or spray-on aerosol fluid.
In a particularly preferred embodiment the method according to the present invention is carried out on a laundry fabric using aqueous treatment liquor. In particular the treatment may be effected in, or as an adjunct to, an essentially conventional wash cycle for cleaning laundry. More preferably, the treatment is carried out in an aqueous detergent wash liquor. The bleaching composition can be delivered into the wash liquor from a powder, granule, pellet, tablet, block, bar or other such solid form. The solid form can comprise a carrier, which can be particulate, sheet-like or comprise a three-dimensional object. The carrier can be dispersible or soluble in the wash liquor or may remain substantially intact. In other embodiments, the bleac

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Enhancement of air bleaching catalysts does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Enhancement of air bleaching catalysts, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Enhancement of air bleaching catalysts will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3178773

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.