Compositions – Oxidative bleachant – oxidant containing – or generative – Contains activator admixed with inorganic peroxide
Reexamination Certificate
2001-11-16
2003-11-18
Rotman, Alan L. (Department: 1625)
Compositions
Oxidative bleachant, oxidant containing, or generative
Contains activator admixed with inorganic peroxide
C252S186400, C549S396000
Reexamination Certificate
active
06649085
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to the use of certain cyclic sugar ketones for enhancing the bleaching action of peroxygen compounds during the bleaching of colored soilings both on textiles and also on hard surfaces, and to laundry detergents and cleaners which comprise such cyclic sugar ketones.
BACKGROUND OF THE INVENTION
Inorganic peroxygen compounds, in particular hydrogen peroxide and solid peroxygen compounds which dissolve in water to liberate hydrogen peroxide, such as sodium perborate and sodium carbonate perhydrate, have been used for a long time as oxidizing agents for disinfection and bleaching purposes. The oxidation effect of these substances depends heavily on the temperature in dilute solutions; thus, for example, using H
2
O
2
or perborate in alkaline bleach liquors, a sufficiently rapid bleaching of soiled textiles is achieved only at temperatures above approximately 80° C.
At lower temperatures, the oxidation effect of the inorganic peroxygen compounds can be improved by adding “bleach activators”. For this purpose, numerous proposals have been worked out in the past, primarily from the substance classes of N- or O-acyl compounds, for example polyacylated alkylenediamines, in particular tetraacetylglycoluril, N-acylated hydantoins, hydrazides, triazoles, hydrotriazines, urazoles, diketopiperazines, sulfurylamides and cyanurates, and also carboxylic anhydrides, in particular phthalic anhydride and substituted maleic anhydrides, carboxylic esters, in particular sodium nonanoyloxybenzenesulfonate (NOBS), sodium isononanoyloxybenzenesulfonate (ISONOBS) and acylated sugar derivatives, such as pentaacetylglucose. By adding these substances it is possible to increase the bleaching action of aqueous peroxide solutions to the extent that even at temperatures around 60° C. essentially the same effects arise as with the peroxide solution on its own at 95° C.
In efforts for energy-saving washing and bleaching processes, use temperatures significantly below 60° C., in particular below 45° C. down to cold-water temperature have gained in importance in recent years. At these low temperatures, the effect of the activator compounds known hitherto usually noticeably decreases. There has therefore been no lack of attempts to develop more effective activators for this temperature range although hitherto a convincing success has not been recorded.
A starting point for this arises from the use of transition metal salts and complexes thereof, as are described, for example, in EP 0 392 592, EP 0 443 651, EP 0 458 397, EP 0 544 490 or EP 0 549 271. EP 0 630 964 discloses certain manganese complexes which, despite not having a marked effect with regard to a bleach boosting of peroxygen compounds and not decoloring textile fibers, are able to effect bleaching of soil or dye detached from the fiber and present in wash liquors. DE 44 16 438 discloses manganese, copper and cobalt complexes which can carry ligands from a large number of groups of substances and are reportedly used as bleach and oxidation catalysts. WO 97/07191 proposes complexes of manganese, iron, cobalt, ruthenium and molybdenum with ligands of the salene type as activators for peroxygen compounds in cleaning solutions for hard surfaces. The use of metal-containing bleach activators, however, frequently has the disadvantage that damage to the textile fabric can arise under unfavorable conditions.
The literature also describes metal-free bleach catalysts. Thus, U.S. Pat. No. 3,822,114, for example, describes bleaches which, in addition to an organic or inorganic peroxygen compound, comprise ketones or aldehydes as bleach boosters. U.S. Pat. No. 3,822,114 teaches, in tables 2, 3, 4 and 5, the use of a large number of cyclic and open-chain ketones which have good effectiveness at temperatures above 80° F. However, there is neither indications that ketones based on sugar can be used, nor that these are already effective at temperatures below 80° F. WO 95/31527 describes bi- and tricyclic ketones as bleach activators. Decalin-1,5-dione, methyldecalin-1,6-dione and tricycloundecanediones are mentioned as examples. Also described in U.S. Pat. No. 5,785, 887 are open-chain or cyclic monoketals of diketones such as cyclohexanedione as bleach activators. This specification does not give information on ketones based on sugar either.
The aim of the present invention is to improve the oxidation and bleaching action, in particular of inorganic peroxygen compounds, at low temperatures below 80° C., in particular in the temperature range from about 5° C. to 45° C.
SUMMARY OF THE INVENTION
Surprisingly, it has now been found that certain keto group-carrying sugars, in the presence of organic or inorganic peroxygen compounds, contribute significantly to the cleaning performance toward colored soilings present on textiles or on hard surfaces.
The invention provides for the use of cyclic sugar ketones of the formula
in which R
1
and R
2
are hydrogen, C
1
-C
22
-alkyl, C
2
-C
22
-alkenyl or phenyl, R
3
is C
1
-C
4
-alkoxy, phenyl-CH
2
—O— or a group of the formula
R
4
is hydrogen or R
3
and R
4
together are a group of the formula
and n is zero or 1, as catalysts for peroxygen compounds.
DETAILED DESCRIPTION OF THE INVENTION
Corresponding sugar ketones are described, for example, in Z. -X. Wang et al., J. Org. Chem., 1997, 62, 2328-2329, Z. -X. Wang et al., J. Amer. Chem. Soc., 1997, 119, 11224-11235, W. Adam et al., Tetrahedron Asymmetry, 1999,10, 2749-2755 and 1998, 9, 4117-4122. As is known to the person skilled in the art, the ketones can be obtained by acetalation or ketalation of the corresponding sugars and subsequent oxidation of an alcohol function. Oxidation reactions are described, for example, in R. F. Butterworth and S. Hanessian, Synthesis, 1971, 19 and P. H. Grisebach and H. Schmid, Angew. Chem., Int. Ed. Engl., 1972, 11, 159.
As is known from J. Amer. Chem. Soc., 1997, 119, 11224-11235, the sugar ketones can form dioxirane structures in aqueous solution in the presence of peroxy compounds in accordance with the following reaction equation:
These dioxirane compounds represent the actual bleaching agent.
Particularly preferred sugar ketones are:
1,2:4,5-di-O-isopropylidene-D-erythro-2,3-hexodiuro-2,6-pyranose,
1,2:4,5-di-O-isopropylidene-L-erythro-2,3-hexodiuro-2,6-pyranose,
1,2:5,6-di-O-isopropylidene-&agr;-D-glucofuranos-3-ulose hydrate,
methyl-3,4-O-isopropylidene-&bgr;-L-erythropentopyranosid-2-ulose.
Also particularly preferred are the pyranose derivatives of the following formulae 1 to 3, and their lower homologs with C
2
-, C
3
-, C
4
-, C
5
-, C
6
- or C
7
- instead of the C
8
-radical:
The cyclic sugar ketones are used in the laundry detergents and cleaners according to the invention, which also comprise organic or inorganic peroxygen compounds, in concentrations of 0.01-10%, preferably 0.1-8% and in particular 0.5-5%.
Suitable peroxygen compounds are primarily all alkali metal or ammonium peroxosulfates, such as, for example, potassium peroxomonosulfate (industrially: Caroat® or Oxone®). However, it is also possible to use alkali metal perborate mono- or tetrahydrates and/or alkali metal percarbonates, where sodium is the preferred alkali metal. In a particularly preferred embodiment, mixtures of peroxosulfates with perborates or percarbonates in the mixing ratio 1:10 to 10:1, preferably 1:5 to 5:1 are used. The concentration of the inorganic oxidizing agents in the overall formulation of the cleaner is 5-90%, preferably 10-70%.
Additionally or alternatively, the cleaners according to the invention can comprise oxidizing agents on an organic basis in the concentration range 1-20%. These include all known peroxycarboxylic acids, e.g. monoperoxyphthalic acid, dodecanediperoxy acid or phthalimidoperoxycarboxylic acids such as PAP.
The term bleaching is understood here as meaning both the bleaching of soil on the textile surface and the bleaching of soil detached from the textile surface and present in the wash liquor. Analogous statements apply for the bleaching of soilings on hard surf
Reichardt Nicole
Reinhardt Gerd
Clariant GmbH
Covington Raymond
Rotman Alan L.
Silverman Richard P.
LandOfFree
Cyclic sugar ketones as catalysts for peroxygen compounds does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Cyclic sugar ketones as catalysts for peroxygen compounds, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cyclic sugar ketones as catalysts for peroxygen compounds will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3131983