MXPA00004509A - Bleach catalysts - Google Patents

Abstract

The invention relates to bleach catalysts for use in cleaning or detergent compositions. The bleach catalysts used are water-soluble complexes of (a) one or more cobalt ions and, as ligand, (b) one or more aminated and/or alkylated mono- or oligo-saccharides, optionally in reduced or oxidised form, and salts thereof. The complexes according to the invention are good bleach catalysts and have high hydrolytic stability.

Description

BLEACHING CATALYSTS This invention relates to bleach catalysts for use in cleaning or detergent compositions. European laundry detergents usually contain oxygen-based bleaching agents such as sodium perborate or sodium percarbonate. These bleaches work well at temperatures above 60 ° C, but to increase their overall effectiveness at the relatively low wash temperatures that are used today (for example between 40 and 60 ° C), they are used more frequently with what co-or bleach activator compounds are known. The bleach activator, an example in commercial use is tetraacetylethylenediamine (TAED), is typically used at a level of 3-6% in the detergent and reacts stoichiometrically with the persal to provide a stronger oxidizing agent, for example, paracetic acid. This oxidant can whiten, stains better than hydrogen peroxide and also has a higher biocidal activity. However, as wash temperatures continue to drop, as a result of the demand for higher energy efficiency, even commercially used activated bleach systems become less attractive as their performance rapidly decreases below a temperature of 40 °. C. Other . Drawback of these types of activators is their significant contribution to the cost of the detergent formulation, especially compared to the cost of the persal component. Its rate of dissolution at low temperatures can also reduce its effectiveness and can cause localized damage to the color. The development of interfacially active bleach activators, which react with persalts to produce perishables, which in turn are interfacially active, has improved the performance of oxygen bleaches under certain conditions. The technology has meant that lower concentrations of the bleach system in the wash liquor are required to provide equivalent performance since the bleach is effectively focused towards the spots. Sodium nonanoyloxybenzenesulfonate (SNOBS) according to that described in US-A-4, 412, 934 is an example of this type of activator. Although this presentation resulted in the successful introduction of perborate bleach-based detergents in the United States of America where lower concentrations of detergent are typically employed, it has meant little to improve the performance of detergents at temperatures below 40 ° C. Numerous efforts are being made to find new activators of organic bleach, however at present no effort has given a result that meets all the requirements, which must include (I) a significantly improved bleaching activity at a temperature below 40 ° C (II) a high dissolution rate, (III) low cost, (IV) ease of processing in detergent formulations, (V) storage stability, (VI) compatibility with other detergent ingredients, and (VII) non-toxic nature . Another approach considered has been the use of preformed perishes as bleaches. An example of this is diperoxidodecandioic acid (DPDDA). Although this and other examples of preformed perishables can lead to a better bleach performance than tetracetyl ethylenediamine activated perborate (TAED), the perished usually require stabilization coatings (as described, for example, in the US document). -A-4,100,095). Their use can also cause pinhole damage to colored fabrics. Another approach within the detergent industry has been the use of bleach catalysts that work with oxygen bleaches such as sodium perborate or sodium percarbonate. EP-A-237,111 and EP-A-443,651 describe bleach compositions comprising a water soluble complex of manganese with a multidentate ligand such as hydroxycarboxylic acid and polyhydroxy compounds without carboxylate, respectively. EP-A-272,030 and EP-A-392, 592 present complexes of Co (III) amine (for example, [Co (NH3) 5C1] C12) and complexes of Co (bispyridylamine) Cl2 respectively, as effective catalysts for the activation of hydrogen peroxide compounds in the removal of substrate stains, such as fabrics. Other patent specifications, for example WO 96/23859, WO 96/23860 and WO 96/23861, present cobalt catalysts such as [Co (NH3) 5C1] C12 and Co-SALEN type complexes to provide improved benefits cleaning / bleaching in detergents in automatic dishwashers. Catalysts described by Hage et al., In Nature 369, 637-639 (1994) and also in EP-A-458,397 and EP-A-458,398 are examples that offer a considerable improvement to bleaching by persalts of fabric spots during Washing at temperatures below 40 ° C. However, these catalysts have a tendency to cause unacceptable damage to color and fabrics due to the formation of catalyst decomposition products. Another important feature of bleach catalysts is their hydrolytic stability. The lack of hydrolytic stability of the catalysts can result in precipitation, under alkaline washing conditions, of insoluble transition metal oxides or insoluble transition metal hydroxides which results in an increase of undesirable brown spots. It is therefore important that the complex used as a catalyst has a good hydrolytic activity on the one hand, but that it also continues to have good effectiveness as a bleach catalyst on the other hand. It has now been surprisingly found that water soluble complexes of cobalt with monosaccharides or oliginated and / or alkylated oligosaccharides, optionally in reduced and oxidized form, and salts thereof have a high effectiveness as bleach catalysts and have a high hydrolytic stability. . According to one aspect of the present invention, there is provided a water-soluble complex of (a) one or more cobalt ions and, as a ligand, (b) one or more monosaccharides or oligosaccharides to and / or alkylated, optionally in reduced form or oxidized, and salts thereof for use as a bleach catalyst, particularly for cleaning or detergent composition. Suitably, in the complex employed according to the present invention, the cobalt ion (s) (a) form (n) complexes with (b) one or more compounds of the general formula I wherein R1 is selected from CH2OH, COH2, C02 ~ ~ (where M is an ammonium or alkali metal ion) and groups of the formulas (a) to (d) and n is an integer from 1 to 3; one of R2 and R3 is H and the other is selected from H, OH and groups of the formulas (e) to (h) and m is an integer from 1 to 3; one of R4 and R5 is H and the other is OH; one of R6 and R7 is H and the other is OH or NH2; and one of R8 and R9 is H and the other is OH, 0CH2 (CH2) PCH3 (where p is an integer from 6 to 16), or a group of the formula provided that one of R6 and R7 is NH2 and / or one of R8 and R9 is OCH2 (CH2) pCH3. Likewise, in the complex used according to the present invention, the cobalt ion (s) (a) can (n) form complexes with (b) one or more compounds of the general formula II R, 1 ^ 0 [, C1E21-k. { OE) k] CBR11 (II) I NH2 where each of R10 and R11, which may be the same or different, represents H, CH2OH, C02H, or C02"M" (where M is in accordance with that defined above); and each of 1 and k is an integer from 2 to 5 and k is equal to 1 or less than 1. Preferably, the cobalt ion (s) (a) form (n) complexes with (b) D- mannosamine, D-glucosamine, or D-galactosamine, or with (b) one or more alkyl polyglucosides having a degree of polymerization of up to 5 and where the alkyl groups contain from 8 to 18 carbon atoms. Suitably, the complex employed according to the invention is a Co (II) or Co (III) complex. The complexes used according to the invention can be prepared by a method comprising contacting in an aqueous solution (A) a water-soluble compound capable of releasing Co (II) or Co (III) ions upon addition. to water with (B) one or more monosaccharides or oligosaccharides aminated and / or optionally alkylated in reduced or oxidized form, and salts thereof. For example, cobalt chloride hexahydrate (0.53 g) and mannosamine hydrochloride (24.1 g) were dissolved in 500 ml of demineralized water, the pH of the solution was adjusted to 10 using a 1M sodium hydroxide solution and the solution was evaporated to dryness in a rotary evaporator. The molar ratio between the ligand and the cobalt can generally be within a range of 1: 1 to 500: 1 with ratios in the region of 50: 1, for example 20: 1 to 80: 1 being particularly preferred. In accordance with another aspect of the present invention, there is provided a cleaning or detergent composition comprising: (I) a bleaching agent; and (II) a bleach catalyst, a water soluble complex according to the definition according to the present invention. The cobalt bleach catalyst can be formed in situ at the beginning of the wash cycle and in fact it is preferable that it be formed in situ at the beginning of said wash cycle. Accordingly, in accordance with a further aspect of the invention, there is provided a cleaning or detergent composition comprising: (I) a whitening agent, and as precursors to the bleach catalyst, (IIA) a water soluble compound capable of releasing ions Co (II) or Co (III) when added to water and (IIB) one or more monosaccharides or oligosaccharides, amino and / or alkylated, optionally in reduced or oxidized form, and salts thereof. The water-soluble Co2 + or Co3 + compound (HA) must be a compound that forms complexes preferably with the compounds (IIB) in the composition. These compounds can be cobalt chloride or cobalt compounds with weak complex formation. The complexes used according to the invention promote the bleaching activity and this is particularly visible at low temperatures (ie from 20 to 40 ° C). The bleaching agent (I) will generally be a peroxy compound that releases hydrogen peroxide in water, preferably sodium perborate or sodium percarbonate. The ligand component of the bleach catalyst of (b) or precursor ingredient (IIB) may suitably be a cyclic ligand of formula I. Some of the ligands of formula I have surfactant properties that provide additional cleaning benefits in terms of oily solids and in particles, particularly. The ligand compounds used in accordance with the present invention are derived from starches or from carbohydrates which occur naturally and are therefore environmentally acceptable and toxicologically inert. The compositions according to the invention may be laundry detergents or hard surface cleaners including automatic dishwashing detergents and may comprise other ingredients well known to those skilled in the art. They may contain a bleach activator, for example, TAED.

The compositions according to the present invention may contain a surfactant, for example, an anionic surfactant such as for example linear or nonionic alkyl alcohol benzenesulfonate or alkyl benzene sulphonate such as for example an alcohol ethoxylate. In addition, the compositions according to the present invention generally contain building elements such as aluminosilicates (eg, zeolite A), layered silicates, phosphate, particularly sodium tripolyphosphate, trisodium citrate, sodium carbonate or sodium borate. Also, polymeric derivatives such as maleic / acrylic copolymers that act as building coelements, and stain release polymers such as polyethylene oxide terephthalate may be present. The compositions according to the present invention may also contain suds suppressors such as for example soaps; enzymes such as for example lipase, amylase, cellulase and protease; optical brighteners such as stilbene derivatives; sequestering agents or a combination of sequestering agents with low affinity for cobalt but that form complexes with other transition metals and, if this is not the case, at a sufficiently low level they do not affect the performance of the catalyst, as well as flow auxiliaries. fillers such as sodium sulfate.

Typically, in the case of detergent formulations according to the present invention, considering a typical detergent use level of 5 g / 1 (Europe), an appropriate level of cobalt chloride hexahydrate and, for example, a mannosamine ligand in the detergent formulation would be of the order of 0.024% by weight and 1.08%, respectively.

In use, the cobalt level can be, for example within a range of 0.85 to 85 μmoles Co / liter of wash liquor (from 0. 05 to 5 ppm). More detailed information on typical detergent compositions is presented, for example in WO 92/06161. The invention is further described in the following examples. EXAMPLE 1 Comparison of bleaching performance of tea stain from mixed systems of cobalt salt / organic / persal polyol with. organically activated persalts at a temperature of 40 ° C.

The test wash liquor was prepared from 1 liter of deionized water to which was added as appropriate: (a) 5 x 10 ~ 6 M CoCl2.6H20 (CoCl2.6H20) (b) 8.6 x 10 ~ 3 M H202, as a peroxygen source to provide active oxygen in solution, and 8.6 x 10 ~ 3 M sodium metaborate as a borate regulator to simulate the use of sodium perborate (PBS), (c) 8.6 x 10-3 M H202, as was peroxygen, and 5.7 x 10 ~ 3 M sodium carbonate as a carbonate buffer to simulate sodium percarbonate (PCS), (d) 6. 6 x 10-4 M tetraacetylethylenediamine (TAED), as activator, (e) 2.5 x 10"" 4 M of the specified polyhydro compound to provide a bleach system in accordance with that set forth in Table I below. - Bleaching tests were carried out on a Terg-o-tometer (United States Testing Co.) at a temperature of 40 ° C. The pH was monitored at which it was maintained at a level of 10 using dilute sulfuric acid or a sodium hydroxide solution as needed. Four samples of 10 x 10 cm2 of cotton stained with tea (BC1) were used in the bleaching studies. The duration of the washing was 31 minutes. ~ ~ The reflectance of all samples was measured before and after washing in a HunterLab UltraScan XE spectrophotometer. The change in reflectance of the washed and unwashed fabrics (? R) was calculated at the established wavelength and the four? R values were averaged to provide a global value per wash. The results appear in table I below. TABLE I Bleaching system? R46o PBS 67.27 PBS + TAED _ 8.40 PCS 7.18 PCS + TAED 7.90 PBS + C? Cl2.6H20 9.86"PCS + CoCl2.6H20 11.75 PBS + CoCl2.6H20 + D-manosamine 10.25 PCS + CoCl2.6H20 + D-manosamine 11.89 PBS + CoCl2.6H20 + Simulsol SL 10 * 11.81 PCS + CoCl2.6H20 + Simulsol SL 10 11.23 PBS + C0CI2.6H2O + D-glucosamine 9.8_4 PCS + CoCl2.6H20 + D-glucosamine 10.96 PBS + CoCl2 .6H20 + D-galactosamine 10.27 PCS + CoCl2.6H20 + D-galactosamine 10.71 * Simulsol SL 10 (formerly SEPPIC) is a mixture of alkyl polyglycosides having a degree of polymerization of up to 4, 1-4 (50%) and 1-6 (50%) of interglucosidic links and where the algil groups are predominantly decyl. Hydrolytic stability tests were carried out in a molar ratio of 10 ligand: ICo2- as C0CI2.6H2O (0.5 mmol ligand / 0.05 mmol Co2-). Where indicated, PBS was added as 8.6 x 10 ~ 3 M sodium metaborate and 8 ^ 6 x 10 ~ 3 M H202, and PCS was added as 5.7 x 10 ~ 3 M ~ sodium carbonate and 8.6 x 10 ~ 3 M H2O. The test solutions were prepared in deionized water and all solutions were adjusted to a pH of 10 before the addition of Co. The results are shown in Table II below. TABLE II Composition of stable solution * stable * after after 1 hour 24 hours CoCl2.6H20 yes no CoCl2.6H20 + PBS yes no C0CL2-.6H2O + PCS yes no C0CI2..6H2O + D-mannosamine + PBS yes yes CoCl2. 6H20 + D-manosamine + PCS yes yes C0CI2.6H2O + Simulsol SL 10 + PBS yes yes C0CI2.6H2O + Simulsol SL 10 + PCS yes yes CoCl2.6H20 + D-glucosamine + PBS yes yes CoCl2.6H20 + D-glucosamine + PCS yes yes C0CI2.6H2O + D-galactosamine + PBS yes yes CoCl2.6H20 + D-galactosamine + PCS yes yes * stable solutions are defined as optically transparent and do not contain visible precipitate. EXAMPLE 2 Comparison of bleaching performance of tea stain of cobalt salt / organic / persal polyol mixed systems with organically activated persalts at temperatures of 20 ° C, 30 ° C and 40 ° C.

Wash liquors were prepared, as in Example 1, to provide bleaching systems in accordance with that set forth in Table III below. Reflectance and bleach test measurements were carried out as in Example 1, except that the bleaching test temperatures employed were 20 ° C, 30 ° C and 40 ° C. The results appear in Table III below TABLE III Bleaching system? 460 20 ° C 30 ° C 40 ° C PBS 2.98 - 6.27 PBS + TAED 4.53 7.00 8.40 PBS + C0CI2.6H2O 5.35 - 9.86 PBS + CoCl2.6H20 + D-mannosamine 4.69 7.85 10.25 PBS + CoCl2.6H20 + D-Simulsol SL10 6.29 8.08 11.81 EXAMPLE 3 Effect of concentration of peroxide and cobalt salt on the performance of bleaching of tea stain at a temperature of 40 ° C. A test wash liquor composed of 1 liter of deionized water was prepared to which was added, as appropriate: (a) 5 x 10 ~ 6 or 10 x 10"6 M CoCl2.6H20 (b) 8.6 x 10 ~ 3 M H202 and 8.6 x 10 ~ 3 of sodium metaborate or 17.2 x 10 ~ 3 M H202 and 17.2 x 10"3 M sodium metaborate (c) 6.6 x 10 M tetraacetylethylenediamine (TAED) (d) 2.5 x 10"4 M of the polyhydroxy compound specified to provide the bleach system in accordance with the provisions of Table IV below. bleaching and reflectance measurements in accordance with that established in -example 1. The results appear in table IV below.

TAED or compound [CoCl2.6H20] / [H20] (in? R 460 polyhydroxy present x 10"° M borate buffer) / xlO" 3 M TAED 0 8.6 8.40 None 5 8.6 9.86 D-mannosamine 5 8.6 10.25 Simulsol SL 10 5 8.6 11.81 D-mannosamine 10 8.6 12.55 Simulsol SL 10 10 8.6 11.27 TAED 0 17.2 11.54 none 5 17.2 15.50 * D-mannosamine 5 17.2 16.72 Símulsol SL 10 5 17.2 13.62 D-galactosamine 5 17.2 13.24 * a high reflectance value was obtained from the wash containing Co (5xl0 ~ 6 M) + H2O2 (17.2 mmol), however this combination could not be accepted in. laundry conditions due to its hydrolytic instability. EXAMPLE 4 Comparison of the performance of PBS with and without the addition of Co / Simulsol SL 10 salt complex against several stains and grime in washing tests at a temperature of 40 ° C. A test wash liquor composed of 1 liter of deionized water was prepared to which was added, as appropriate (a) 8.6 x 10 ~ 3 M H202 and 8.6 x 10-3 M sodium metaborate (PBS), (b) 6.6 x 10 ~ 4 M TAED, (d) 2.5 x 10"4 M Simulsol SL 10 to provide a bleaching composition in accordance with Table V below: Bleaching tests were carried out using four samples of 10 x 10 cm2 as indicated The protocol for bleaching and bleaching / cleaning studies was in accordance with the bleaching tests of example 1. The reflectance was measured as described in example 1.

The results obtained were in accordance with Table V below. TABLE V Bleaching composition? R460 EMPA BC1C BC2C CS- EMPA 114a 5Sd 101 * PBS / TAED 24.15 8.40 7.71 6.91 18.04 PBS + CoCl2.6H20 + 22.37 11.81 9.12 5.12 23.21 Simulsol SL 10 aEMPA 114 = coton stained with red wine bBCl = coton stained with tea CBC2 = coton stained with coffee dCS-5S = coton stained with mayonnaise / bean eEMPA 101 = coton stained with black smoke / olive oil.

Claims (1)

1. CLAIMS The use of a water-soluble complex of (a) one or more cobalt ions and, as a ligand, (b) one or more aminated and / or alkylated monosaccharides or oligosaccharides, optionally in reduced or oxidized form, and salts thereof , as a bleach catalyst. The use according to claim 1, wherein, in the complex, the cobalt ion (s) (a) forms (s) complexes with (b) one or more compounds of the general formula I where R1 is selected from CH2OH, COH2, C02"M" (where M is an ammonium or alkali metal ion) and groups of the formulas (a) to (d) (c) Ofl and n is an integer from 1 to 3; one of R2 and R3 is H and the other is selected from H, OH and groups of the formulas (e) to (h) 03) Ch) ! and m is an integer from 1 to 3; one of R4 and R5 is H and the other is OH; one of R6 and R7 is H and the other is OH or NH2; and one of R8 and R9 is H and the other is OH, 0CH2 (CH2) PCH3 (where p is an integer from 6 to 16), or a group of the formula provided that one of R6 and R7 is NH2 and / or one of R8 and R9 is 0CH2 (CH2) pCH3. The use according to claim 1, wherein in the complex, the cobalt ion (s) (a) forms (s) complexes with (b) one or more compounds of the general formula II R [C? H2? - k (0H) k] CHR 11 (II) NH NH2 where each of R10 and R11, which may be the same or different, represents H, CH2OH, C02H, or C02 ~ M ~ (where M is in accordance with defined above); and each of 1 and k is an integer from 2 to 5 and k is equal to less than 1. The use according to claim 1, wherein, in the complex, the cobalt ion (s) (a) forms (n) complexes with D-mannosamine, D-glucosamine, or D-galactosamine. The use according to claim 1 wherein, in the complex, the cobalt (ies) io (a) forms (s) complexes with (b) one or more alkyl polyglycosides having a degree of polymerization of up to 5 and where the alkyl groups contain from 8 to 18 carbon atoms. 6. The use according to any of the preceding claims, wherein, in the complex, the cobalt ion or each of the cobalt (a) ions is a Co (II) or Co (III) ion. 7. A cleaning or detergent composition comprising (I) a bleaching agent, and (II) a bleach catalyst, a water-soluble complex according to any one of claims 1 to 6. 8. A composition of cleaning or detergent comprising: (I) a bleaching agent, and as precursors for a bleach catalyst (HA) a water soluble compound capable of releasing Co (II) or Co (III) ions upon addition to water, and ( HB) one or more aminated and / or alkylated monosaccharides or oligosaccharides, optionally in reduced or oxidized form, and salts thereof. 9. A composition according to claim 8, wherein cobalt chloride is used as the component (HA). 10. A composition according to claim 8 or 9 wherein component (IIB) is used as one or more compounds of the general formula I wherein R1 is selected from CH2OH, COH2 / C02 ~ M ~ (where M is an ammonium ion or alkali metal) and groups of the formulas (a) to (d) and n is an integer from 1 to 3; one of R2 and R3 is H and the other is selected from H, OH and groups of the formulas (e) to (h) and is an integer from 1 to 3; one of R4 and R5 is H and the other is OH; one of R6 and R7 is H and the other is OH or NH2; one of R8 and R9 is H and the other is OH, OCH2 (CH2) PCH3 (where p is an integer from 6 to 16), or a group of the formula provided that one of R6 and R7 is NH2 and / or one of R8 and R9 is OCH2 (CH2) pCH3. . A composition according to claim 8 or according to claim 9, wherein one or more compounds of the general formula II are used as component (IIB). NH2 where each of R10 and R11, which may be the same or different, represents H, CHOH, C02H, or "well C0 ~ M ~ (where M is as defined above); and each of 1 and k is an integer from 2 to 5 and k is equal to l or less than 1.. A composition according to claim 8 or 9, wherein D-mannosamine, D-glucosamine, or D-galactosamine is used as component (HB). . A composition according to claim 8 or according to claim 9, wherein one or more alkyl polyglycosides having a degree of polymerization of up to 5 and wherein the alkyl groups contain from 8 to 18 atoms are used as component (IIB). of carbon. . A composition according to any of claims 7 to 13, wherein the bleaching agent (I) is a peroxy compound which liberates hydrogen peroxide in water, preferably sodium perborate or sodium percarbonate.