Title of Invention

LIQUID DYE FORMULATIONS OF NONSULFONATED METAL COMPLEX DYES

Abstract uqina dye formulations of nonsulfonated metal complex dyes The invention relates to liquid dye formulations of nonsulfonated metal complex dyes and to their use for producing aqueous dye liquors, in particular for producing dye liquors for spray-dyeing leather. The liquid dye formulations of the present invention, as well as a nonsulfonated metal complex dye A, comprise a mixture of at least two organic solvents and if appropriate water, the solvent mixture comprising essentially i) at least a first solvent of the hereinbelow defined general formula I which has a solubility in water of more than 100 g/l at 25°C; and ii) at least a second organic solvent which comprises at least one oxygen atom and has a solubility in water of less than 100 g/l at 25°C.
Full Text

Ljquid dye formulations of nonsulfonated metal complex dyes
Description
The invention relates to liquid dye formulations of nonsulfonated metal complex dyes and to their use for producing aqueous dye liquors, in particular for producing dye liquors for spray-dyeing leather.
Leather finishing, in particular leather spray dyeing, frequently utilizes liquid dye formulations of nonsulfonated metal complex dyes, in particular of 1:2 azo metal complex dyes. Applied to the leather sunace, tnese ayes produce strong, ievei io^ dyeings of the leather surface, since the chemical properties of these dyes are such that their tendency to penetrate through the leather is minimal. Depending on field of use and application technique, such metal complex dyes are provided in the form of concentrated stock solutions which are thinned with solvent, but preferably with a mixture of predominantly water and water-miscible solvents, before use as a dyeing liquor or to be more precise a spraying liquor. Stock solutions generally consist of dye dissolved in a water-miscible solvent or solvent mixture of water-miscible solvents and if appropriate a low fraction of water and customary additives. The water-miscible solvents used for this purpose are chiefly lower alcohols such as methanol, ethanol, isopropanol, glycols, polyglycols and their monoethers and monoesters.
Depending on the quality of the water used for setting the liquor, in particular in the case of hard water, i.e., water comprising calcium and magnesium ions, sparingly solubles form in the spraying liquor in the course of and after thinning and lead to undesirable effects in relation to the dyeing, in particular the effect known as "bronzing". This is allowed for in commercial practice by employing higher fractions of organic solvents in the liquor. But this diminishes the desired strong top color effect on the leather surface, since the increased solvent fraction means that a large portion of the dye is carried into the leather matrix.
A customary measure to improve the stability of liquid dye formulations of such dyes and to reduce bronzing is to use suitable cosolvents. These are generally additives which are miscible with water in any proportion, in particular lactams such as N-methylpyrrolidone, N-alkylamides such as dimethylformamide and dimethylacetamide and also N-alkylureas such as tetramethylurea. Base solvents for the dyes are respectively freely water-miscible alcohols, glycols, polyglycols, their freely water-miscible monoethers, monoesters and their mixtures and also ethylene carbonate and propylene carbonate. N-Alkylated carboxamides and lactams, such as N-methylpyrrolidone (NMP), dimethylformamide (DMF) and dimethylacetamide

PMAC), however, have an elevated toxic potential and therefore are undesirable on occupational hygiene and consumer protection grounds. In addition, some of these agents actually are not capable of conferring a sustained improvement in the stability of nonsulfonated metal complex dye formulations to thinning with water, in particular hard Abater.
DE-A 28 02 326 describes concentrated liquid dye formulations which as well as a dye,
water and/or a water-miscible organic solvent and also
at least one nonionic hydrotrope, for example a reaction product of a Ci-Ce-alkanol, of a monoalkyl- or monoalkylolamine or of a polyalkylenepolyamine with propylene oxide, a reaction product of an aliphatic rnonGaikanc! having at least 8 carbon atoms and an alkylene oxide etc., the reaction product having a molecular weight in the range from 2000 to 7000, and at least one further constituent selected from the group consisting of anionic surfactants of polyether structure and reaction products of a fatty acid with 1 to 2 mol of diethanolamine.
EP-A-169 816 describes liquid anionic dye formulations comprising a d-C4-monoalkyl ether of propylene glycol or of butylene glycol and/or its Ct-C4 monocarboxylic ester as solvent.
EP 00 524 520 describes liquid dye formulations for leather dyeing which, besides one or more ionogenic metal-free azo dyes and/or metal-containing azo and/or azomethine dyes, comprise at least one alkoxy alcohol, at least one solvent selected from the lactones, lactams and cyclic ureas, and water.
However, prior art liquid dye formulations are not entirely satisfactory in the case of nonsulfonated metal complex dyes, in particular in the case of nonsulfonated 1:2 azo metal complex dyes, in particular with regard to the color strengths achieved and the occurrence of bronzing effects.
It is an object of the present invention to provide such liquid dye preparations of nonsulfonated metal complex dyes, in particular of liquid dye preparations of nonsulfonated 1:2 azo metal complex dyes, as overcome the disadvantages of the prior art, i.e., as possess good stability to thinning with water, in particular with hard water, and at the same time reduce the occurrence of bronzing effects and as make it possible to achieve high color strengths.
We have found that this object is achieved, surprisingly, by the hereinbelow described liquid dye formulations which, as well as a nonsulfonated metal complex dye A,

comprise a mixture of at least two organic solvents and if appropriate water, the solvent mixture comprising essentially
i) at least a first solvent of the hereinbelow defined general formula I which has a solubility in water of more than 100 g/l at 25°C; and
ii) at least a second organic solvent which comprises at least one oxygen atom and has a solubility in water of less than 100 g/l at 25°C.
The present invention accordingly provides liquid dye formulations of a nonsulfonated metal complex dye A, comprising at lease an organic meta* complex aye ana a mixture of organic solvents and also if appropriate water, the mixture of organic solvents comprising essentially, i.e. in an amount of at least 90% by volume, in particular at least 95% by volume and specifically at least 99% by volume, based on the total amount of organic solvents in the liquid dye formulation,
i) at least one first solvent of the general formula I

where k represents 1, 2 or 3, R represents CrC6-alkyl and A represents 1,2-ethanediyl, 1,2-propanediyl or 1,3-propanediyI, the solvent of the formula I having a solubility in water of more than 100 g/l at 25°C; and
ii) at least a second organic solvent which comprises at least one oxygen atom and has a solubility in water of less than 100 g/l at 25°C.
The liquid dye formulations of the present invention are stable to prolonged storage even at a comparatively high temperature and do not give rise to any significant precipitates, if any at all, on thinning with water, in particular with water which is hard, i.e., comprises magnesium and/or calcium ions, in particular on thinning with water having a total hardness (concentration of alkaline earth metal ions per liter) of at least 1.3 mmol/L, in particular at least 2 mmoi/L and specifically >2.5 mmol/L (corresponding to a water hardness of at least 7° German hardness, in particular at least 11 ° German hardness and specifically at least 14° German hardness). When used for surface dyeing leather as for example by spray dyeing, aqueous liquors produced by thinning the liquid dye preparations of the present invention with water, in particular with hard water having a total water hardness >1.3 mmol/L, in particular >2 mmol/L and specifically >2.5 mmol/L, lead to a lesser extent to bronzing effects and/or deeper shades than comparable liquid dye preparations of the prior art.

Accordingly, the present invention also provides for the use of the liquid dye formulation of the present invention for producing an aqueous dye liquor, in particular for producing an aqueous dyeing liquor by thinning with hard water, i.e., water having a total hardness of at least 1.3 mmol/L, in particular at least 2 mmol/L and specifically >2.5 mmol/L.
Here and hereinbelow the term alkyl (and also corresponding groups in alkoxy, alkoxyalkyl, alkyisulfonyl, alkylaminosulfonyl, dialkylaminosulfonyl and alkylcarbonyl-amino) represents a linear or branched aliphatic hydrocarbyi radical. The designation Cn-Cm in this context indicates the number of carbon atoms possessed by the respective radical. Accordingly, CrC4-alkyi and CrC6-aikyi represent aliphatic hydrocarbyi radicals having respectively from 1 to 4 carbon atoms and from 1 to 6 carbon atoms, examples being methyl, ethyl, n-propyl, isopropyl, n-butyl, 2-butyl, 2-methylpropyl, tert-butyl, n-pentyi, 2-pentyl, 1,1-dimethylpropyl, n-hexyl, 2-hexyl, 2-methylpropan-2-yl and the like.
R represents in particular Ci-C^alkyl in the solvents of the formula I. The variable k represents in particular 2.
Examples of solvents of the formula I are 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, 2-butoxyethanol, 2-methoxypropan-1-ol, 1-methoxypropan-2-ol, 2-ethoxypropan-1-ol, 1-ethoxypropan-2-ol, 2-isopropoxypropan-1-ol, 1-isopropoxy-propan-2-ol, 2-isobutoxypropan-1-ol, 1-isopropoxypropan-2-oI, 2-(2-methoxy-ethoxy)ethanol, 2-(2-ethoxyethoxy)ethanol, 2-(2-butoxyethoxy)ethanol (= C4H9-(0-CH2CH2)2-OH), 2-[2-(ethoxyethoxy)ethoxy)ethanoI, 2-[2-(butoxyethoxy)-ethoxy]ethanol, dipropylene glycol monomethyl ether (= CH3-(0-C3H6)2-OH) and dipropylene glycol monoethyl ether (= C2H5-(0-C3H6)2-OH) and also mixtures thereof. Examples of preferred solvents I are methoxypropanols such as 1-methoxypropan-2-ol, 2-methoxypropan-1-ol, 2-(2-methoxyethoxy)ethanol, 2-(2-ethoxyethoxy)ethanol, 2-(2~butoxyethoxy)ethanol, dipropylene glycol monomethyl ether and dipropylene glycol monoethyl ether. Of these, particular preference is given to methoxypropanol, for example technical grade 1-methoxypropan-2-ol, 2-(2-butoxyethoxy)ethanol and dipropylene glycol monomethyl ether.
The solvents of the formula I which are present in the liquid dye formulations of the present invention have a solubility in water of more than 100 g/l at 25°C and are preferably selected from such compounds as are fully miscible with water at 25°C.
The amount of solvent of the formula I present in the liquid dye preparations of the present invention is preferably in the range from 20% to 80% by weight, in particular in

the range from 30% to 70% by weight and specifically in the range from 40% to 60% by weight, based on the total weight of the liquid dye formulation.
The organic solvent comprising at least one oxygen atom may in principle be any low molecular weight organic substance, i.e., an organic substance having a molecular weight n-butanol, isobutanol, alkanols having at least 5 carbon atoms, in particular 5 to 16 carbon atoms and specifically 5 to 14 carbon atoms such as amyl alcohol, isoamyl alcohol, hexanols such as n-hexanol, 2-ethyl-1-butanol, 4-methyl-2-pentanol, 2-ethylhexanol, isononanol, n-nonanol, technical grade mixtures of isomeric nonyl alcohols, 2-propylheptanol, isotridecanol, technical grade mixture of isomeric isotridecanols, and the like;
cycioalkanols having at least 5 carbon atoms in particular having 5 to 12 carbon atoms such as cyciopentanol, cyclohexanol, cycloheptanol, 2-, 3- and 4-methylcyclohexanol, 3,3,5-trimethylcyclohexanol and the like;
aliphatic and cycloaliphatic ketones having at least 5 carbon atoms, in particular having 5 to 12 carbon atoms such as diethyl ketone, methyl propyl ketone, methyl butyl ketone, methyl isobutyl ketone, cyclohexanone, methylcyclo-hexanone, dimethylcyclohexanone, 3,3,5-trimethylcyclohexanone, isophorone and the like;
C2-Ci0-alkyl esters and C5-Ci0-cycloalkyl esters of aliphatic CrC4 carboxylic acids, in particular of acetic acid such as ethyl acetate, n-propyl acetate, n-butyl acetate, isobutyl acetate, sec-butyl acetate, n-amyl acetate, isoamyl acetate, hexyl acetate, 2-ethylhexyl acetate, octyl acetate, nonyl acetate, cyclohexyl acetate, 2-butoxyethyl acetate, and also the corresponding propionates and butyrates;

1
esters of compounds i with aliphatic CrC4 carboxylic acids, in particular with acetic acid such as butyiglycol acetate and butyldiglycol acetate;
diols having at least 6 carbon atoms in particular 8 to 12 carbon atoms such as 2-ethylhexane-1,3-diol and 2,4-diethyloctane-1)5-diol and also mixtures thereof, for example technical grade mixtures such as high-boiling fractions from the hydroformylation of alkenes, such as Oxooel 740 (CAS 68551-11-1, main constituents: 2-ethylhexane-1,3-diol and n-butanol) and Oxooel 800 (CAS 68609-68-7, main constituent: 2,4-diethyloctane-1,5-dioI).
The amount of the second organic solvent, comprising at least one oxygen atom, present in the liquid dye formulations of the present invention is preferably in the range from 1% to 40% by weight, in particular in the range from 5% to 30% by weight and specifically in the range from 10% to 25% by weight, based on the total weight of the liquid dye formulation.
The liquid dye formulations of the present invention may further comprise water, in which case the fraction of water in the liquid dye formulation preferably does not exceed 30% by weight and is for example in the range from 5% to 30% by weight and in particular in the range from 10% to 20% by weight, based on the total weight of the liquid dye formulation.
The amount of metal complex dye A present in the liquid dye formulations of the present invention is generally in the range from 2% to 30% by weight, in particular in the range from 5% to 20% by weight and specifically in the range from 8% to 15% by weight, based on the total weight of the liquid dye formulation. The dye fraction is reckoned on the basis of the metal complex with any counter-ions on the assumption of complete conversion in the synthesis of the dye.
The dye A may in principle be any nonsulfonated metal complex dye, i.e., any metal complex dye devoid of sulfonic acid groups or anionic sulfonate groups. Nonsulfonated dyes are insoluble or substantially insoluble in water because of the absence of solubilizing sulfonic acid groups or sulfonate groups.
The metal complex dyes A can be neutral or charged, the net charge of the complex naturally being dependent on the charge of the metal cation and of the ligand and being typically 0, -1 or -2, although in the case of ca'rboxylate-substituted ligands it may also be -2 or -3 at high pH values, for example pH > 8 and especially > 9, depending on the number of carboxylate groups. The metal complex dyes then have cations as counter-ions for reasons of electroneutrality. The counter-ions are in particular alkali metal ions, in particular sodium or lithium ions or ammonium ions such as NH4+, mono-,

di-, tri- and tetra-CrC^alkylammonium, hydroxyethyiammonium, hydroxypropyl-amrnonium, bis(hydroxyethyl)ammonium, bis(hydroxypropyl)ammonium, tris(hydroxyethyI)ammoniurn, tris(hydroxypropyl)ammonium, bis(hydroxyethyl)-CrC4-alkylammonium and bis(hydroxypropyl)-CrC4-alkyIammonium.
The metal complex dyes are generally complexes of nonsulfonated chelating dye molecules comprising transition metals of groups VI to X of the periodic table, for example of Cu, Cr, Fe, Ni, Co, Mn, Zn or Cd, in particular of Cr3\ Co3+ or Fe3+. The molar ratio of transition metal to dye molecule in these metal complexes is typically in the range from 2:1 to 1:2. In general, the metal ions are complexed in these dyes by deprotonated hydroxyl groups, deprotonated carboxyl groups, deprotonatea amino groups, deprotonated imino groups, via nitrogen atoms incorporated in an aromatic TT-electron system, or via azo groups or azomethine groups. Typical ligands are mono-and bisazo dyes, porphyrins, azomethine dyes and the like.
In a preferred embodiment of the present invention, the dye A is a symmetrical or asymmetrical 1:2 metal complex of a mono- or disazo dye or a mixture of such dyes. One skilled in the art will understand by this metal complexes of chelating ligands from the group of the ortho-ortho'-(o,o,)-disubstituted monoazo or o,o'-disubstituted disazo dyes with multivalent metal cations, for example 2-, 3- or 4-valent metal cations, in particular of transition metal cations, examples being Cr3", Co3+ or Fe3+. Appropriately substituted azomethine dyes are similarly useful as chelating ligands.
Symmetrical and asymmetrical metal complexes may respectively be described by the general formulae [MLJ* and [MLL']k, where L and L' represent chelating ligands from the group of o,o-disubstituted monoazo and disazo dyes, M represents a multivalent metal cation, for example a 2-, 3- or 4-valent metal cation, and in particular a transition metal cation, for example Cr3*, Co3+ or Fe3\ and k represents the net charge of the complex and is generally -1.
Typically, the o,o'-disubstituted ligands are o-carboxy-o'-hydroxy, o-hydroxy-o'-amino or o,o'-dihydroxy azo dyes of the benzene-azo-benzene type, of the benzene-azo-naphthalene type, of the naphthalene-azo-naphthalene type, of the benzene-azo-pyrazolone type, of the benzene-azo-pyridone type or of the benzene-azo-acetoacetanilide type, and the benzene, naphthalene, pyrazolone, pyridone and anilide groups may in turn comprise further substituents, selected for example from the group consisting of halogen, nitro, cyano, OH, COOH, CrC4-alkyl, CrC4-alkoxy, CrC4-alkoxy-CrC^alkyl, Ci-C4-alkylsulfonyl, aminosulfonyl, mono-or di-CrC4-alkylaminosulfonyl, CrC4-alkylsulfonylamino, CrC4-alkylcarbonylamino, -N=N-phenyl, phenyl and phenylsulfonylamino, the phenyl radical in the last three groups mentioned itself being unsubstituted or substituted by 1, 2 or 3 identical or different substituents

selected from the group consisting of halogen, nitro, cyano, OH, COOK CrC4-alkyl, C1-C4-aikoxy, CrC4-alkoxy~C-rC4-alkyl, C^-C^alkylsulfonyl, aminosulfonyi, mono- or di-CrC4-aIkylaminosulfonyl and CrC4-alkylsutfonylamino.
More particularly, the free iigands of the metal complex dye A can be described by the formulae L1-H2 or L2-H2:

where
X-H and Y-H independently represent OH, NH2 or COOH, X in particular being OH or COOH and Y in particular being OH;
n, m and o independently represent 0,1, 2 or 3;
A represents an aromatic radical selected from the group consisting of phenyl, naphthyl, pyridyl and pyrazolyl, in particular from the group consisting of phenyl, 1-naphthyl, 2-naphthyI and 4-pyrazolyl,
R1 in each occurrence is independently selected from the group consisting of
halogen, nitro, cyano, OH, COOH, CrC4-alkyl, CrC4-alkoxy, CrC4-alkoxy-C1-C4-alkyl, CrC4-alkylsulfonyl, aminosulfonyi, mono- or di-CrC^alkylaminosulfonyl, CrC4-alkylsulfonylamino, CrC4-alkylcarbonylamino, phenyl and phenylsulfonylamino, the phenyl radical in the last two groups mentioned being unsubstituted or substituted by 1, 2 or 3 identical or different substituents selected from the group consisting of halogen, nitro, cyano, OH, COOH, CrC4-alkyl, CrC4-alkoxy, Ci-C4-alkoxy-CrC4*alkyl, Ci-C4-alkylsulfonyl, aminosulfonyi, mono- or di-CrC4-alkylaminosulfonyl and d-C^alkylsulfonylamino, although one R1 radical may also be an N=N-Ph group where Pfr represents a phenyl radical which is unsubstituted or substituted by 1, 2 or 3 identical or different substituents selected from the group consisting of halogen, nitro, cyano, OH, COOH, Ci-C4-

alkyi, (VC^alkoxy, C^C^alkoxy-CVC^alkyl, Ci-C^alkylsulfonyl, aminosulfonyl, mono- or di-CrC4-aikyiaminosulfonyi and CrC4-aIkylsuifonylamino;
R2 and R3 are independently selected from the group consisting of halogen, nitro,
cyano, OH, COOH, NH2, CrC4-alkyl, CrC4-alkoxy, CrC^alkoxy-d-C^alkyt, Cr C4-aIkylsulfonyl, aminosulfonyl, mono-or di-CrC4-alkyiaminosulfonyl, CfC4-alkylcarbonylamino and CrC4-aIkylsulfonylamino, or one of R2 and R3 may also be an N=N-Ph group where Ph represents a phenyl radical which is unsubstituted or substituted by 1, 2 or 3 identical or different substituents selected from the group consisting of halogen, nitro, cyano, OH, COOH, CrC4-alkyl, CrC4-alkoxy, CrC^alkoxy-CrC^alkyl, CrC4-alkylsulfonyl, aminosulfonyl, mono- or di-Ct-C4-alkylaminosulfonyl and Ci^-aikylsulfonylamino; and
R4 represents CrC4-alkyl, in particular methyl.
More particularly, the A(R1)m group represents phenyl, phenyl-N=N-phenyl, 1-naphthyl, 2-naphthyl and 1-phenyl-3-methylpyrazol-4-yl, where phenyl, naphthyl and the phenyl groups in phenyl-3-methylpyrazol-4-yI and phenyl-N=N-phenyl may comprise 1 or 2 from the group consisting of halogen, nitro, cyano, OH, NH2, d-C^alkyl, CrC4~aIkoxy, CrC4-alkoxy-CrC4-alkyl, CrC4-a!kylsulfonyl, aminosulfonyl, mono- or di-CrC4-alkylaminosulfonyl, d^-alkylcarbonylamino and CrC4-aikylsulfonylamino.
n is in particular 0, 1 or 2. Preferred R1 substituents comprise nitro, chlorine, cyano, OH, CrC4-alkyl, Ci^-alkoxy, CrC4-alkylsulfonyI, aminosulfonyl, mono-or di-C-i-CA-alkylaminosulfonyl, CrC4-aIkylcarbonylamino and Ci-d-alkylsulfonylamino.
Examples of ligands of the formula L1-H2 are the compounds L1-H2-1 to L1-H2-53 identified in Table A.
Table A: Ligands of the formula L1-H2:






f
Examples of 1:2 meta! complexes preferred according to the present invention are in particular the symmetrical complexes of the formula [(L1)2Cr]1" and [(L1)2Co]1~, where L1 represents a ligand derived from the free ligands L1-H2.1 to L1-H2.53 identified in Table A.
Examples of 1:2 metal complexes preferred according to the present invention further include in particular the asymmetrical complexes of the formula [(L1)(L1')Cr]1_ and [(L1)(L1')Co]1', where L1 and L1' represent two different ligands derived from the free ligands L1-H2.1 to L1-H2.53 identified in Table A.
Examples of 1:2 metal complexes preferred according to tne present invention airther include in particular the asymmetrical complexes of the formula [(L1)(L2)Cr]1_ and [(L1)(L2)Co]1", where L1 represents a ligand derived from one of the free ligands L1-H2.1 to L1-H2.53 identified in Table A and L2 represents a ligand derived from one of the free ligands L2-H2.1 to L2-H2.20 identified in Table B.
The metal complex dyes A are known or preparable by analogy to known methods of the prior art. Metal complexes of monoazo and disazo dyes and their preparation are described for example in DE-A 26 33 154, DE 28 02 326, EP-A 19 152, EP-A 24 609 and EP-A 524 520.
The liquid dye formulations of the present invention are notable for improved stability to thinning with water and in particular with hard water. They are therefore particularly useful for producing aqueous dyeing liquors, since when liquor production is by thinning the liquid dye formulations of the present invention with water the hardness of the water used for thinning is less problematical than in the case of prior art liquid dye formulations.
The liquid dye formulations of the present invention can in principle be used for producing any desired aqueous dyeing liquors. However, the present invention's advantages come to bear in particular in the surface dyeing of leather and specifically in the spray-dyeing of leather, since the improved stability to hard water reduces the formation of insolubles in the aqueous liquor so that bronzing effects are reduced or completely avoided and strong surface dyeings are possible. Accordingly, a preferred embodiment of the present invention relates to the use of liquid dye formulations of the present invention for producing an aqueous liquor for the surface dyeing and in particular for the spray-dyeing of leather.
The present invention further provides a process for dyeing substrates, in particular leather, and specifically a process for surface dyeing leather by application of an aqueous dyeing liquor produced by thinning a liquid dye formulation according to the

present invention with water, specifically with hard water, in a particularly preferred embodiment, the present invention provides a process for surface dyeing leather by spray application of a dyeing liquor thus produced.
Dyeing processes for leather and other substrates involving the use of aqueous dyeing liquors will be well known to those skilled in the art, for example in the case of leather from "Bibliothek des Leders" Band 5 (Das Farben von Leder) [1987] Umschau Verlag; "Leather Technicians Handbook", 1983, by J. H. Sharphouse, published by Leather Producers Association; and "Fundamentals of Leather Manufacturing", 1993, by E. Heidemann, published by Eduard Roether KG.
The aqueous dyeing liquors may, depending on the method of application and the substrate to be dyed, customary auxiliaries, examples thereof in the case of leather dyeing being agents to set the pH, fatliquors, tanning agents, retanning agents, hydrophobicizers, fixatives, penetrants and binders in the customary amounts. In the case of the surface dyeing which is preferred according to the present invention, the aqueous dyeing liquor (a spray liquor), as well as the aforementioned dyes and solvents, may typically comprise further constituents. These include further water-miscible solvents, agents to set the pH, for example organic acid and/or bases, also penetration aids, hydrophobicizers, binders composed of natural or synthetic, water-soluble or water-insoluble polymers and also reactive crosslinkers. They may also comprise fatliquors, retanning agents and/or cationic fixatives, if appropriate. The fraction of such auxiliary materials in the liquor may be a multiple of that of the dye.
The process of the present invention is in principle useful for all types of leather, i.e., nonretanned intermediate products such as metal oxide tanned leather (wet-blue in the case of chromium oxide tanning and wet-white in the case of aluminum oxide tanning) and organically, for example aldehydically, tanned leather (wet-white) or vegetable-tanned leather, and also retanned intermediate products such as crust material.
Dyeing is effected in the customary apparatus for the method of application, in the case of spray-dyeing, for example, manually or mechanically by atomizers for liquids, for example by means of air-atomizing spray guns, HVLP (high volume low pressure) guns or by means of airless atomizers. Application is typically at temperatures in the region of the ambient temperature, for example in the range from 10 to 50°C. This is generally followed by a drying operation, for example at temperatures in the range from 60 to 140°C.
The inventive and comparative examples which follow illustrate the invention.

Dyes:
Dye A: mixture of symmetrical and asymmetrical 1:2 chromium complexes of the ligands L1-H2.1 and L1-H2.2 from Table A, prepared similarly to DE 2918634 by diazotization of a mixture of 2-amino-5-nitrophenol and 2-amino-4-nitrophenol, coupling onto (3-naphthol and subsequent chroming with chromium(lli) salts. Solution in butyldiglycol (2-(2-butoxyethoxy)ethanof).
Dye B: symmetrical 1:2 cobalt complex of the ligand L1-H2.2 from Table A, prepared similarly to DE 2918634 by diazotization of 2-amino-5-nitrophenol, coupling onto p-naphthol and subsequent metalization with CoCI2 x 6 H20. Solution in butyldiglykol or dipropylene glycol monomethyl ether.
Dye C: asymmetrical 1:2 chromium complex of the ligands L1-H2.5 and L1-H2,11 from Table 1, prepared similarly to DE 2918634 by diazotization of a mixture of 2-amino-5-nitrophenol with anthranilic acid (molar ratio 1:1), coupling onto p-naphthol and subsequent chroming with chromium(lll) salts. Solution in butyldiglycol or dipropylene glycol monomethyl ether.
I. Liquid dye formulations:
1.1 Liquid dye formulations of dye A
The solution of dye A in butyldiglycol is adjusted to a customary, storage-stable concentration and about pH 8 with the respective solvent or solvent mixture as per Table 1, completely ion-free water and, if appropriate, 20% aqueous sodium hydroxide solution.
1.2 Liquid dye formulations of dye B
The solution of dye B in butyldiglycol or in dipropylene glycol monomethyl ether is adjusted to a customary, storage-stable concentration and about pH 8 with the respective solvent or solvent mixture as per Table 1, completely ion-free water and, if appropriate, 20% aqueous sodium hydroxide solution.
1.3 Liquid dye formulations of dye C
The solution of dye C in butyldiglycol or in dipropylene glycol monomethyl ether is adjusted to a customary, storage-stable concentration and about pH 8 with the respective solvent or solvent mixture as per Table 1, completely ion-free water and, if appropriate, 20% aqueous sodium hydroxide solution.



1 ■ I ■ ' ■ ' ■ ■ '
1) weight ratio
2) Nonanol N: mixture of isomeric primary nonyl alcohols (CAS Reg. No. 68515-81-1)
3) acetic ester of 2-butoxyethanol
4) acetic ester of 2-(2-butoxyethoxy)ethanol
5) V = comparative example
Abbreviations:
PM; 1-methoxy-2-propanol
NMP: N-methylpyrrolidone
DAA: diacetone alcohol (= 2-oxo-4-hydroxy-4-methylpentane)
BDG: butyldiglycol
DPM: dipropylene glycol monomethyl ether
PC: propylene carbonate
EC: ethylene carbonate
II. Application examples
The stock solutions are used to produce spray mixtures according to the following recipes:
A 75 parts of stock solution
325 parts of 1-methoxy-2-propanol (technical grade)
600 parts of completely ion-free water, rendered completely ion free by
conventional methods
B 100 parts of stock solution
200 parts of 1-methoxy-2-propanol (technical grade) 700 parts of hard water

The hard water is prepared by dissolving 260.0 mg of CaCI2 x 6 H20 and 145.4 mg of MgS04 x 7 H20 in distilled water to form a 100 ml solution and thinning with distilled water to 500 ml.
Commercial standard undyed chrome cattle hide leather is spray-dyed by means of conventional spray guns using about 4.5 g of spraying liquor per A6-sized piece of leather. The leather is dried at room temperature and evaluated and colorimetrically measured after complete drying (after at least 1 day).
The evaluation for bronzing is done by visual inspection using the following ratings:
Mark 5 = none 4 = weak 3 = moderate 2 = medium
1 - strong
The color strength of the dyeings is assessed in terms of the lightness difference L* or dL* (CIELAB system) according to German Standard Specification DIN 6174:1979-01 compared with a reference sample: the smaller the value (dL* negative compared with a control dyeing), the greater the intensity, the depth of shade of the dyeing.
The color strengths and bronzing effects obtained by method A and by method B are used to calculate plus points for every liquid dye formulation. This is done by performing at least 2 comparative dyeings with noninventive dye formulations for each series. The worst value achieved for a given series (lowest depth of shade, most severe bronzing) is assigned the value "0". A noticeable improvement in one property scores 1 plus point, a distinct improvement 2. The plus points of a sample are then summed over all properties assessed.
The results of the dyeings are summarized in Table 2.
Table 2











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1149-CHE-2005 CORRESPONDENCE OTHERS 09-08-2010.pdf

3860-chenp-2007 amended claims 30-06-2011.pdf

3860-chenp-2007 correspondence others 30-06-2011.pdf

3860-CHENP-2007 AMENDED CLAIMS 08-11-2010.pdf

3860-CHENP-2007 AMENDED PAGES OF SPECIFICATION 08-11-2010.pdf

3860-CHENP-2007 EXAMINATION REPORT REPLY RECIEVED 08-11-2010.pdf

3860-CHENP-2007 FORM-13 08-11-2010.pdf

3860-chenp-2007 form-3 08-11-2010.pdf

3860-CHENP-2007 OTHER PATENT DOCUMENT 08-11-2010.pdf

3860-chenp-2007-abstract.pdf

3860-chenp-2007-claims.pdf

3860-chenp-2007-correspondnece-others.pdf

3860-chenp-2007-description(complete).pdf

3860-chenp-2007-form 1.pdf

3860-chenp-2007-form 18.pdf

3860-chenp-2007-form 26.pdf

3860-chenp-2007-form 3.pdf

3860-chenp-2007-form 5.pdf

3860-chenp-2007-pct.pdf


Patent Number 248694
Indian Patent Application Number 3860/CHENP/2007
PG Journal Number 32/2011
Publication Date 12-Aug-2011
Grant Date 05-Aug-2011
Date of Filing 04-Sep-2007
Name of Patentee BASF AKTIENGESELLSCHAFT
Applicant Address D-67056, LUDWIGSHAFEN
Inventors:
# Inventor's Name Inventor's Address
1 ADAMS, STEFAN WISSMANNSTRASSE 77, 67065 LUDWIGSHAFEN, GERMANY.
2 REINHARDT, ROBERT FREIHEITSSTRASSE 12, 67149 MECKENHEIM
3 DORNER, MICHAEL KARL-BLUM-WEG 4, 64625 BENSHEIM, GERMANY.
4 BUCHHOLZ, OLIVER AMSELSTRASSE 16, 68623 LAMPERTHEIM, GERMANY.
5 HEISER, STEPHAN DEIDESHEIMER STRASSE 10, 67161 GONNHEIM, GERMANY.
PCT International Classification Number C09B 67/44
PCT International Application Number PCT/EP2006/001978
PCT International Filing date 2006-03-03
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 102005010022.8 2005-03-04 Germany