Cleaning compositions for solid surfaces – auxiliary compositions – Cleaning compositions or processes of preparing – For cleaning a specific substrate or removing a specific...
Reexamination Certificate
2001-05-08
2003-03-25
DelCotto, Gregory (Department: 1751)
Cleaning compositions for solid surfaces, auxiliary compositions
Cleaning compositions or processes of preparing
For cleaning a specific substrate or removing a specific...
C510S303000, C510S372000, C510S376000, C510S500000, C008S111000, C502S200000, C252S186330, C252S186390
Reexamination Certificate
active
06537959
ABSTRACT:
This invention relates to compositions and methods for catalytically bleaching substrates, more particularly using a defined class of ligand or complex as catalyst, and further relates to ligands and complexes useful in such compositions and methods.
Peroxygen bleaches are well known for their ability to remove stains from substrates. Traditionally, the substrate is subjected to hydrogen peroxide, or to substances which can generate hydroperoxyl radicals, such as inorganic or organic peroxides. Generally, these systems must be activated. One method of activation is to employ wash temperatures of 60° C. or higher. However, these high temperatures often lead to inefficient cleaning, and can also cause premature damage to the substrate.
A preferred approach to generating hydroperoxyl bleach radicals is the use of inorganic peroxides coupled with organic precursor compounds. These systems are employed for many commercial laundry powders. For example, various European systems are based on tetraacetyl ethylenediamine (TAED) as the organic precursor coupled with sodium perborate or sodium percarbonate, whereas in the United States laundry bleach products are typically based on sodium nonanoyloxybenzenesulfonate (SNOBS) as the organic precursor coupled with sodium perborate.
Precursor systems are generally effective but still exhibit several disadvantages. For example, organic precursors are moderately sophisticated molecules requiring multi-step manufacturing processes resulting in high capital costs. Also, precursor systems have large formulation space requirements so that a significant proportion of a laundry powder must be devoted to the bleach components, leaving less room for other active ingredients and complicating the development of concentrated powders. Moreover, precursor systems do not bleach very efficiently in countries where consumers have wash habits entailing low dosage, short wash times, cold temperatures and low wash liquor to substrate ratios.
Alternatively, or additionally, hydrogen peroxide and peroxy systems can be activated by bleach catalysts, such as by complexes of iron and the ligand N4Py (i.e. N,N-bis(pyridin-2-yl-methyl)-bis(pyridin-2-yl)methylamine) disclosed in WO95/34628, or the ligand Tpen (i.e. N,N,N′,N′-tetra(pyridin-2-yl-methyl)ethylenediamine) disclosed in WO97/48787.
Although many types of bleach catalysts are known in the art, nevertheless there still remains a need for further classes of bleach catalysts.
According to WO95/34628 or WO97/48787, molecular oxygen may be used as the oxidant as an alternative to peroxide generating systems. However, no role in catalysing bleaching by atmospheric oxygen in an aqueous medium is reported. It has long been thought desirable to be able to use atmospheric oxygen (air) as the source for a bleaching species, as this would avoid the need for costly hydroperoxyl generating systems. Unfortunately, air as such is kinetically inert towards bleaching substrates and exhibits no bleaching ability. Recently some progress has been made in this area. For example, WO 97/38074 reports the use of air for oxidising stains on fabrics by bubbling air through an aqueous solution containing an aldehyde and a radical initiator. A broad range of aliphatic, aromatic and heterocyclic aldehydes is reported to be useful, particularly para-substituted aldehydes such as 4-methyl-, 4-ethyl- and 4-isopropyl benzaldehyde, whereas the range of initiators disclosed includes N-hydroxysuccinimide, various peroxides and transition metal coordination complexes.
However, although this system employs molecular oxygen from the air, the aldehyde component and radical initiators such as peroxides are consumed during the bleaching process. These components must therefore be included in the composition in relatively high amounts so as not to become depleted before completion of the bleaching process in the wash cycle. Moreover, the spent components represent a waste of resources as they can no longer participate in the bleaching process.
Accordingly, it would be desirable to be able to provide a bleaching system based on atmospheric oxygen or air that does not need to rely primarily on hydrogen peroxide or a hydroperoxyl generating system, and that does not require the presence of organic components such as aldehydes that are consumed in the process. Furthermore, it would be desirable to be able to provide a bleaching system that is capable of being based either on atmospheric oxygen/air or on hydrogen peroxide/hydroperoxyl-generating systems as a source of the primary bleaching species, or on both. Moreover, it would be desirable to provide such bleaching systems that are effective in aqueous medium.
It may also be noted that the known art teaches a bleaching effect only as long as the substrate is being subjected to the bleaching treatment. Thus, there is no expectation that hydrogen peroxide or peroxy bleach systems could continue to provide a bleaching effect on a treated substrate, such as a laundry fabric after washing and drying, since the bleaching species themselves or any activators necessary for the bleaching systems would be assumed to be removed from the substrate, or consumed or deactivated, on completing the wash cycle and drying.
It would be therefore also be desirable to be able to treat a textile such that, after the treatment is completed, a bleaching effect is observed on the textile. Furthermore, it would be desirable to be able to provide a bleach treatment for textiles such as laundry fabrics whereby residual bleaching occurs when the treated fabric has been treated and is dry.
We have found that a selected class of ligand or complex is surprisingly effective in catalysing the bleaching of substrates, either using atmospheric oxygen or air, or using hydrogen peroxide or a hydroperoxyl generating system, or using both. Furthermore, we have found certain novel ligands and complexes which are useful in the bleaching of substrates.
Accordingly, in a first aspect, the present invention provides a compound of the general formula (I):
wherein
Z represents a group selected from —NH
2
, —NHR
4
, —N(R
4
)
2
, —N(R
4
)
3
+
, —NO
2
, —NHC(O)R
4
, —N(R
4
)C(O)R
4
(wherein R
4
represents alkyl, cycloalkyl, aryl, arylalkyl or heteroarylalkyl, each optionally substituted by —F, —Cl, —Br, —I, —NH
3
+
, —SO
3
H, —SO
3
−
(Na
+
, K
+
), —COOH, —COO
−
(Na
+
, K
+
), —P(O)(OH)
2
, or —P(O)(O
−
(Na
+
, K
+
))
2
), an optionally substituted heterocyclic ring or an optionally substituted heteroaromatic ring selected from pyridine, pyrimidine, pyrazine, pyrazole, imidazole, benzimidazole, quinoline, quinoxaline, triazole, isoquinoline, carbazole, indole, isoindole, oxazole and thiazole;
each Q independently represent a group of the formula:
wherein
5≧a+b+c≧1; a=0-5; b=0-5; c=0-5; n=1 or 2;
Y independently represents a group selected from —O—, —S—, —SO—, —SO
2
—, —C(O)—, arylene, alkylene, heteroarylene, heterocycloalkylene, —(G)P—, —P(O)— and —(G)N—, wherein G is selected from hydrogen, alkyl, aryl, arylalkyl, cycloalkyl, each except hydrogen being optionally substituted by one or more functional groups E;
R1, R2, R3, R5, R6, R7, R8 independently represent a group selected from hydrogen, hydroxyl, halogen, —R and —OR, wherein R represents alkyl, alkenyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl or a carbonyl derivative group, R being optionally substituted by one or more functional groups E,
or R5 together with R6, or R7 together with R8, or both, represent oxygen,
or R5 together with R7 and/or independently R6 together with R8, or R5 together with R8 and/or independently R6 together with R7, represent C
1-6
-alkylene optionally substituted by C
1-4
-alkyl, —F, —Cl, —Br or —I; and
E independently represents a functional group selected from —F, —Cl, —Br, —I, —OH, —OR′, —NH
2
, —NHR′, —N(R′)
2
, —N(R′)
3
+
, —C(O)R′, —OC(O)R′, —COOH, —COO
−
(Na
+
, K
+
), —COOR′,
Appel Adrianus Cornelis
Hage Ronald
Russell Stephen William
Tetard David
DelCotto Gregory
Honig Milton L.
Unilever Home & Personal Care USA , division of Conopco, Inc.
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