Bleach activating cyanopyridinium compounds

0001This invention relates to the use of cyanopyridinium compounds as bleach activators and detergent compositions containing these quaternary bleach activators.

0002It is known that the bleaching power of peroxidic bleaching agents such as perborates, percarbonates, persilicates and perphosphates can be improved so that the bleaching action begins at lower temperatures, for example at or below 60 ° C., by adding the precursors of bleaching peroxyacids which often referred to as bleach activators.

0003Many substances are known in the art as bleach activators. These are usually reactive organic compounds with an O-acyl or N-acyl group which form the corresponding peroxy acids in alkaline solution together with a source of hydrogen peroxide.

0004Representative examples of bleach activators are, for example, N, N, N ', N'-tetraacetylethylenediamine (TAED), glucose pentaacetate (GPA), xylose tetraacetate (TAX), sodium 4-benzoyoxybenzenesulfonate (SBOBS), sodium trimethylhexanoyloxybenzenesulfonate (TetraHolUlSulfonate (TetraHolUtol) glucosulfonate (STetraHolUlol) glucosulfonate (TetraHolurolSulfonate) Tetraacetylcyanoic acid (TACA), di-N-acetyldimethylglyoxin (ADMG) and 1-phenyl-3-acetylhydantoin (PAH). For example, reference is made to GB-A-836 988, GB-A-907 356, EP-A-0 098 129 and EP-A-0 120 591.

0005In the meantime, cationic peroxyacid precursors, which contain, for example, a quaternary ammonium group in addition to O-acyl or N-acyl groups, have become more important because they are highly effective bleach activators. Such cationic peroxyacid precursors are described, for example, in US Pat. No. 5,460,747, US Pat. No. 5,047,577, US Pat. No. 4,933,103, US Pat. No. 4,751,015, US Pat. No. 4,397,757, GB-1,382,594, WO-95 21150, EP -A-403 152, EP-A-427 224, EP-A-402 971, EP-371 809, EP-A-284 292 and EP-A-284 292. Corresponding free, stable quaternary peracids are described, for example, in EP-340 754 and WO-94 01399.

0006Ammonium nitriles of the formula<chemistry id="chem0001" num="0001"><img file="EP0806473A2_D0001.tif" /></chemistry> form a special class of cationic bleach activators. Compounds of this type and their use as bleach activators in bleaching agents are described in EP-A-303 520, EP-A-464 880, EP-A-458 396 and US-A-4 883 917. On the one hand, the quaternary charge appears to have an increased solubility on the other hand to cause a preferred fiber affinity. EP-303 520 in particular describes the use of 3-cyano-N-methylpyridinium iodide as a bleach activator.

0007Surprisingly, it has now been found that quaternary nitriles, which are derived from 2- or 4-cyanopyridinium salts, have a better bleaching effect than bleach activators according to the prior art.

0008The invention thus relates to the use of the compounds of the general formula I as bleach activators,<chemistry id="chem0002" num="0002"><img file="EP0806473A2_D0002.tif" /></chemistry><ul id="ul0001" list-style="none" compact="compact"><li>where R₁ Hydrogen, C₁- to C₂₄-Alkyl, C₂-C₂₄-Alkenyl, aryl, cyanomethyl or C₁-C₄-Alkoxy-C₁-C₄-Alkyl means</li><li>R₂, R₃ and R₄ independently of one another hydrogen, C₁- to C₂₄-Alkyl, C₂-C₂₄Alkenyl, aryl, C₁-C₄-Alkoxy-C₁-C₄Are alkyl or cyano, and<ul id="ul0002" list-style="none" compact="compact"><li>a) Z is cyano, and Y has the same meaning as R₂, R₃ and R₄, or</li><li>b) Y is cyano and Z has the same meaning as R₂, R₃ and R₄,</li></ul></li><li>and X is an anion.</li></ul>

0009For R₁ unsubstituted C₁- to C₁₀-Alkyl groups, C₂- to C₄-Alkenyl groups or phenyl groups used.

0010The alkyl and alkenyl groups under the definition of R₁, R₂, R₃ and R₄ can be substituted or unsubstituted. For R₂, R₃ and R₄ independently of one another, unsubstituted C.₁- to C₄-Alkyl groups, unsubstituted C₂- to C₄-Alkenyl groups, phenyl groups or hydrogen are used.

0011The anion X used is preferably chloride, bromide, iodide, fluoride, sulfate, hydrogen sulfate, carbonate, hydrogen carbonate, phosphate, mono- and di-hydrogen phosphate, pyrophosphate, metaphosphate, nitrate, methosulfate, dodecyl sulfate, dodecylbenzenesulfonate, phosphonate, methyl sulfonate, methane sulfonate, methane sulfonate Ethanesulfonate used.

0012N-Alkyl-4-cyanopyridinium salts which carry hydrogen on the ring and alkyl substituents on the nitrogen atom, such as N-methyl-4-cyanopyridinium chloride, N-ethyl-4-cyanopyridinium chloride and N-hexyl-4-cyanopyridinium chloride, are particularly preferred.

0013These compounds are likely to form both peroxyimidic acids and hydroperoxide derivatives in perhydrolysis as a bleaching species.

0014The synthesis routes to the cyanopyridinium compounds according to the invention are to be illustrated using a general example.

0015Isonicotinonitrile is known from the literature and is obtained by direct oxidation of 4-methylpyridine or by ammonium oxidation of 4-methylpyridine. By alkylation of the isonicotinonitrile z. B. with methylating agents such as methyl chloride or dimethyl sulfate at temperatures between 20 and 100 ° C, preferably between 70 and 80 ° C, the corresponding N-alkyl-4-cyanopyridinium salts are obtained. The other cyanopyridinium salts can be prepared in an analogous manner.

0016The invention also relates to the use of these cyanopyridinium compounds in bleaching detergents and cleaning agents. In addition to a peroxy compound and the cationic bleach activator, these washing and cleaning agents usually also contain surface-active compounds and other known ingredients.

0017Suitable peroxy compounds are alkali peroxides, organic peroxides such as urea peroxide, and inorganic persalts, such as the alkali perborates, percarbonates, perphosphates, persilicates and persulfates. Mixtures of two or more of these compounds are also suitable. Sodium perborate tetrahydrate and in particular sodium perborate monohydrate are particularly preferred. Sodium perborate monohydrate is preferred because of its good storage stability and its good solubility in water. Sodium percarbonate may be preferred for environmental reasons.

0018Alkyl hydroperoxides are another suitable group of peroxy compounds. Examples of these substances are cumene hydroperoxide and t-butyl hydroperoxide.

0019In such detergents and cleaning agents, the cyanopyridinium bleach activator according to the invention can be present in a weight fraction of approximately 0.1% to 20%, preferably 0.5% to 10%, in particular 1% to 7.5%, together with a peroxy compound . The proportion by weight of these peroxy compounds is usually from 2% to 40%, preferably from 4% to 30%, in particular from 10% to 25%, the molar ratio of peroxide anion to bleach activator being from 1500: 1 to 1: 2.

0020In addition to the cyanopyridinium bleach activators according to the invention, the detergents and cleaning agents can also contain other suitable bleach activators, such as TAED.

0021The surface-active substance can be derived from natural products, such as soap, or is a synthetic compound from the group of the anionic, nonionic, amphoteric, zwitterionic or cationic surface-active substances, or mixtures thereof. Many suitable substances are commercially available and are described in the literature, for example in "Surface active agents and detergents", Vol. 1 and 2, by Schwartz, Perry and Berch. The total proportion of the surface-active compounds can be up to 50% by weight, preferably 1% by weight to 40% by weight, in particular 4% by weight to 25% by weight.

0022Synthetic anionic surfactants are typically water-soluble alkali metal salts of organic sulfates and sulfonates with alkyl groups of about 8 to 22 carbon atoms, the term "alkyl" including the alkyl substituents of higher aryl groups.

0023Examples of suitable anionic detergents are sodium and ammonium alkyl sulfates, especially those obtained by sulfating higher (C₈ to C₁₈) Alcohols obtained sulfates; Sodium and ammonium alkylbenzenesulfonates with an alkyl radical of C₉ to C₂₀, in particular linear secondary sodium alkylbenzenesulfonates with an alkyl radical of C.₁₀ to C₁₅; Sodium alkyl glycerol ether sulfates, especially the esters of higher alcohols derived from tallow and coconut oil; the sodium sulfates and sulfonates of the coconut fatty acid monoglycerides; Sodium and ammonium salts of higher sulfuric acid (C₉ to C₁₈) oxyalkylated fatty alcohols, in particular the fatty alcohols oxyalkylated with ethylene oxide; the reaction products of the esterification of fatty acids with isethionic acid and subsequent neutralization with sodium hydroxide; Sodium and ammonium salts of the fatty acid amides of methyl taurine; Alkane monosulfonates such as those from the reaction of α-olefins (C₈-C₂₀) with sodium bisulfite and those from the reaction of paraffins with SO₂ and Cl₂ followed by basic hydrolysis, resulting in a mixture of different sulfonates; Sodium and ammonium dialkyl sulfosuccinates with alkyl residues of C₇ to C₁₂; and olefin sulfonates which are used in the reaction of olefins, in particular C₁₀- to C₂₀-α-olefins, with SO₃ and subsequent hydrolysis of the reaction products. The preferred anionic detergents are sodium alkylbenzenesulfonates with alkyl radicals of C.₁₅ to C₁₈, and sodium alkyl ether sulfates with alkyl radicals of C₁₆ to C₁₈.

0024Examples of suitable nonionic surface-active compounds, which are preferably used together with anionic surface-active compounds, are in particular the reaction products of alkylene oxides (usually ethylene oxide) with alkylphenols (alkyl residues of C.₅ to C₂₂), the reaction products generally containing 5 to 25 ethylene oxide units (EO) in the molecule; the reaction products are more aliphatic (C₈ to C₁₈) primary or secondary, linear or branched alcohols with ethylene oxide, with generally 6 to 30 EO, and the addition products of ethylene oxide to reaction products of propylene oxide and ethylenediamine. Other nonionic surfactants are alkyl polyglycosides, long chain tertiary amine oxides, long chain tertiary phosphine oxides and dialkyl sulfoxides.

0025Amphoteric or zwitterionic surface-active compounds can also be used in the compositions according to the invention, but this is mostly undesirable because of their high cost. If amphoteric or zwitterionic compounds are used, this is usually done in small amounts in compositions which mainly contain anionic and nonionic surfactants.

0026Soaps can also be used in the compositions according to the invention, preferably in a proportion of less than 25% by weight. They are particularly suitable in small amounts in binary (soap / anionic surfactant) or in ternary mixtures together with nonionic or mixed synthetic anionic and nonionic surfactants. The soaps used are preferably the sodium salts, and less preferably the potassium salts of saturated or unsaturated C.₁₀- to C₂₄Fatty acids, or mixtures thereof. The proportions of such soaps can be from 0.5% by weight to 25% by weight, smaller amounts from 0.5% by weight to 5% by weight are generally sufficient for foam control. Soap contents between about 2% and about 20%, especially between about 5% and about 10%, have a positive effect. This is particularly the case in hard water, where the soap serves as an additional builder.

0027The washing and cleaning agents generally also contain a builder. Possible builders are: calcium-binding substances, precipitants, calcium-specific ion exchangers and their mixtures. Examples of calcium binding agents include alkali metal polyphosphates such as sodium tripolyphosphate; Nitrilotriacetic acid and its water-soluble salts; the alkali metal salts of carboxymethyloxysuccinic acid, ethylenediaminetetraacetic acid, oxydisuccinic acid, mellitic acid, benzene polycarboxylic acids, citric acid; and polyacetal carboxylates as disclosed in U.S. 4,144,226 and U.S. 4,146,495.

0028Examples of precipitants are sodium orthophosphate, sodium carbonate and soaps from long-chain fatty acids.

0029Examples of ion exchangers which are specific for calcium are the various types of water-insoluble, crystalline or amorphous aluminum silicates, of which the zeolites are the best known representatives.

0030These builder substances can be present from 5% by weight to 80% by weight, a proportion of 10% by weight to 60% by weight being preferred.

0031In addition to the ingredients already mentioned, the washing and cleaning agents can contain any of the conventional additives in amounts that are usually found in such agents. Examples of these additives include foaming agents such as alkanolamides, especially the monoethanolamides made from palm kernel oil fatty acids and coconut fatty acids; anti-foaming agents such as alkyl phosphates and silicones; Graying inhibitors and similar auxiliaries such as sodium carboxymethyl cellulose and alkyl or substituted alkyl cellulose ethers; Stabilizers such as ethylenediaminetetraacetic acid; Softeners for textiles; inorganic salts such as sodium sulfate; and, usually in small amounts, fluorescent substances, perfumes, enzymes such as proteases, cellulases, lipases and amylases, disinfectants and dyes. The bleach activators of this invention can be used in a variety of products. These include textile detergents, textile bleaches, surface cleaners, toilet cleaners, dishwasher cleaners, and also denture cleaners. The detergents can be in solid or liquid form.

0032For reasons of stability and manageability, it is advantageous to use the bleach activators in the form of granules which contain a binder in addition to the bleach activator. Various methods for producing such granules are described in the patent literature, for example in CA-1 102 966, GB-1 561 333, US-4 087 369, EP-A-0 240 057, EP-A-0 241 962, EP-A-0 101 634 and EP-A-0 062 523. Each of these methods can be used for the bleach activators according to the invention.

0033The granules containing the bleach activators are generally added to the detergent composition along with the other dry ingredients such as enzymes, inorganic peroxide bleaches. The detergent composition to which the activator granules are added can be obtained in various ways, such as dry blending, extrusion, spray drying.

0034In a broad embodiment, the bleach activators according to the invention are particularly suitable for non-aqueous liquid detergents, together with a bleaching peroxy compound, for example sodium perborate, in order to give the detergent great cleaning power for fabrics and textiles. Such non-aqueous liquid detergents, including pasty and gelatinous detergent compositions, are known in the art and are described, for example, in U.S. 2,864,770, U.S. 2,940,938, U.S. 4,772,412, U.S. 3,368,977. GB-A-1205 711 GB-A-1 370 377, GB-A-1 270 040, GB-A-1 292 352, GB-A-2 194 536, DE-A-2 233 771, EP-A- 0 028 849.

0035These are compositions in the form of a non-aqueous, liquid medium in which a solid phase can be dispersed. The non-aqueous, liquid medium can be a liquid, surface-active substance, preferably a non-ionic surface-active substance; a non-polar liquid medium such as liquid paraffin; a polar solvent, such as polyols, for example glycerol, sorbitol, ethylene glycol, possibly in combination with low molecular weight monohydric alcohols such as ethanol or isopropanol; or mixtures thereof.

0036The solid phase can consist of builder substances, alkalis, abrasive substances, polymers and other solid ionic surfactants, bleaches, fluorescent substances and other common solid ingredients.

0037The following non-exhaustive examples are intended to provide an overview of the embodiments of the invention.

Example 1:

00389.3 g (0.05 mol) of methyl toluenesulfonate are added dropwise to 5.2 g of 4-cyanopyridine (0.05 mol) in 25 ml of toluene at room temperature. The mixture is then heated to 110 ° C. for 30 minutes. The colorless precipitate which precipitates on cooling is filtered off with suction, 9.9 g (68%) of N-methyl-4-pyridinium tosylate (mp. 167 ° C.) are obtained.

Example 2:

0039A bleaching composition was obtained by combining 200 ml of an aqueous solution of 5 g / l reference detergent (WMP) obtained from WFK-Testgewebe GmbH, Krefeld, 150 mg sodium perborate monohydrate (PB * 1) and 50 mg of an activator. Four pieces of tissue soiled with black tea (BC-1 tea on cotton, 1.25 g, WFK) were added for a thirty-minute isothermal washing experiment in a Linitest device. The fabric pieces were rinsed with water, dried and ironed after the specified washing time. The bleaching effect was then determined using an ELREPHO 2000 whiteness measuring device (Datacolor) by determining the differences in the remissions before and after bleaching.

0040The investigations were repeated with different types of soiling (e.g. grass, curry).

0041The bleaching agent compositions given in Table 1 with the activators 1 and 2 and the comparative compound 3 were prepared. Their effectiveness was determined by comparing the remissions of the fabric before and after the bleaching process. The results are shown in Table 1. The ΔΔ R values ​​indicate the improvement in the bleaching effect of the composition according to the invention compared to PB * 1 and TAED:<maths id="math0001" num=""><math display="block"><mrow><mtable><mtr><mtd><mrow><mtable><mtr><mtd><mrow><mtext>Δ Δ R CP-PB * 1 = Δ R (CP) - Δ R (PB * 1)</mtext></mrow></mtd></mtr><mtr><mtd><mrow><mtext>Δ Δ R CP -TAED = Δ R (CP + TAED) - Δ R (TAED)</mtext></mrow></mtd></mtr></mtable></mrow></mtd></mtr></mtable></mrow></math><img file="EP0806473A2_D0003.tif" /></maths>

0042Compounds 1 to 3 are<chemistry id="chem0003" num="0003"><img file="EP0806473A2_D0004.tif" /></chemistry><tables id="tabl0001" num="0001"><table frame="all"><title>Table 1</title><tgroup cols="5" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="31.50mm" /><colspec colnum="2" colname="col2" colwidth="31.50mm" /><colspec colnum="3" colname="col3" colwidth="31.50mm" /><colspec colnum="4" colname="col4" colwidth="31.50mm" /><colspec colnum="5" colname="col5" colwidth="31.50mm" /><thead valign="top"><row><entry namest="col1" nameend="col1" align="center">Activator no.</entry><entry namest="col2" nameend="col2" align="center">Δ R (CP)</entry><entry namest="col3" nameend="col3" align="center">Δ R (CP + TAED)</entry><entry namest="col4" nameend="col4" align="center">Δ Δ R (CP)</entry><entry namest="col5" nameend="col5" align="center">Δ Δ R (CP-TAED)</entry></row></thead><tbody valign="top"><row><entry namest="col1" nameend="col1" align="center">PB * 1</entry><entry namest="col2" nameend="col2" align="char" char=",">10,8</entry><entry namest="col3" nameend="col3" /><entry namest="col4" nameend="col4" /><entry namest="col5" nameend="col5" /></row><row><entry namest="col1" nameend="col1" align="center">TAED</entry><entry namest="col2" nameend="col2" /><entry namest="col3" nameend="col3" align="char" char=",">12,9</entry><entry namest="col4" nameend="col4" /><entry namest="col5" nameend="col5" /></row><row><entry namest="col1" nameend="col1" align="center">1</entry><entry namest="col2" nameend="col2" align="char" char=",">26,3</entry><entry namest="col3" nameend="col3" align="char" char=",">23,9</entry><entry namest="col4" nameend="col4" align="center">15,5</entry><entry namest="col5" nameend="col5" align="center">11</entry></row><row><entry namest="col1" nameend="col1" align="center">2</entry><entry namest="col2" nameend="col2" align="char" char=",">16,7</entry><entry namest="col3" nameend="col3" align="char" char=",">16,6</entry><entry namest="col4" nameend="col4" align="center">5,9</entry><entry namest="col5" nameend="col5" align="center">3,7</entry></row><row rowsep="1"><entry namest="col1" nameend="col1" align="center">3</entry><entry namest="col2" nameend="col2" align="char" char=",">14,9</entry><entry namest="col3" nameend="col3" align="char" char=",">13,4</entry><entry namest="col4" nameend="col4" align="center">4,1</entry><entry namest="col5" nameend="col5" align="center">0,5</entry></row></tbody></tgroup></table></tables>

0043The washing experiments show that the bleach activators according to the invention provide better washing results than the comparison substance 3.