MXPA96006667A

MXPA96006667A - Acuo coloring solutions

Info

Publication number: MXPA96006667A
Application number: MXPA/A/1996/006667A
Authority: MX
Inventors: Kaser Adolf; Hohener Alfred; Frick Roland
Original assignee: Ciba Sc Holding Ag
Priority date: 1995-12-22
Filing date: 1996-12-19
Publication date: 1997-06-01

Abstract

The aqueous coloring solutions of the composition shown in claim 1 are distinguished by good storage stability and are suitable for dyeing paper in shades of red color.

Description

AQUEOUS COLORING SOLUTIONS The present invention relates to aqueous dye solutions of red disazo dyes, to processes for their preparation, and to their use for dyeing paper. The use of concentrated aqueous solutions of dyes has gained importance in recent years, in particular due to the advantages these solutions have over dyes in powder form. By using its solutions, the difficulties associated with the formation of dust are eliminated, and users are freed from the delayed and often difficult dissolution of the dye powder in water. The use of concentrated solutions has also been stimulated by the development of continuous dyeing processes for paper, since, in these processes, it is convenient to introduce the solution directly in the blender, or add it in any other suitable point of papermaking. For some dyes, for example, the dyes of Formula (1) defined below, however, the formulation of the concentrated dye solutions presents difficulties, since deposits occur in the concentrated solutions during storage, especially at lower temperatures than the room temperature, and these can not be completely dissolved again, or they can dissolve only with an additional work expense. In addition, the concentrated solutions which are suitable as a commercial form, should give clear solutions comprising from about 1 to 3 weight percent of dye, without a precipitate, when diluted for the preparation of the dyeing bath, and this also it should be applied on the widest possible pH scale. The present invention was based on the object of providing concentrated solutions suitable for the dyes of Formula (1) defined below. It has now been discovered that the dye solutions described below meet the requirements imposed in an outstanding manner. Accordingly, the present invention relates to A) concentrated aqueous coloring solutions comprising: a) at least 5 weight percent, based on the weight of the solution, of a red dye of the Formula: wherein: R and Rlf independently of each other, are each hydrogen, Cl, methyl or methoxy, R2 and * 3 'independently of each other, are each hydrogen, methyl or methoxy, R4 and R5 »independently of each other, are each hydrogen, or alkyl of 1 to 4 carbon atoms, A is an unbranched or branched alkylene radical, which may be interrupted by O, and R6 and R7, independently of each other, are each hydrogen or alkyl of 1 to 6 carbon atoms, or where R6 and R7, together with the N atom bonded thereto, form a substituted or unsubstituted 5, 6 or 7 membered ring, which may contain other heteroatoms, b) formic acid or a alkyl acid of 1 to 4 carbon-carboxylic atoms, c) a solubilizing agent, d) water, and if appropriate, e) other additives, or B) concentrated aqueous coloring solutions comprising: a) at least 5.por percent by weight, based on the weight of the solution, of a red dye of Formula (1), b) formic acid or an alkyl acid of 1 to 4 carbon-carboxylic atoms, c) water, and if appropriate, d) other additives, with the proviso that the solutions do not comprise a solubilizing agent , and comprise less than 0.1 weight percent alkali metal halide, based on the total weight of the solution.

The present invention relates preferably to the coloring solutions of group A). In the dyes of Formula (1), R and R are preferably each H, methyl or methoxy, with H.sub.2 preferably being preferred, and R.sup.2 and R.sup.3 are each preferably H. R.sup.4 and R.sup.5 are preferably each methyl or particular, hydrogen. The radicals A are, in particular, alkylene radicals of 2 to 6 carbon atoms, wherein the alkylene chain is straight or branched, or it can also be interrupted by bridging members, for example, -O-, or wherein the alkylene chain is substituted, for example, by OH. A is preferably a radical of the formula - (CH2) n-, wherein n is an integer from 2 to 6. Particularly suitable radicals A are ethylene, normal propylene, isopropylene, or normal butylene. Among these, normal propylene is especially preferred. R6 and R7, independently of each other, are each alkyl of 1 to 6 carbon atoms unsubstituted linear or branched, or alkyl of 1 to 6 carbon atoms which is substituted, for example, by OH or alkoxy of 1 to 4 atoms of carbon. The alkyl chains may also be interrupted, for example, by -0-. Preferably, R6 and R7, independently of one another, are each alkyl of 1 to 4 unsubstituted carbon atoms, and in an especially preferred embodiment, R6 and R7 are identical, and are each methyl or ethyl. A ring of 5, 6 or 7 members of R6 and R7 together with the N atom that joins them, is, in particular, a pyrrolidine, piperidine, morpholine or piperazine ring. The piperazine radical can be substituted on the N atom that is not linked to the alkylene chain, for example, by alkyl. In the dyes of Formula (1), the sulfo group is preferably located in the m position, or in particular in the p position in relation to the azo group. The preferred concentrated solutions according to the invention comprise a dye of the formula: wherein: m is 2, 4 or, in particular, 3, and R6 and R7 are each alkyl of 1 to 2 carbon atoms. The concentration of the dye may vary within wide limits, and is at least 5 weight percent, preferably 6 to 15 weight percent, in particular 8 to 10 weight percent, based on the weight of the dye. the concentrated solution. The alkylcarboxylic acid is, for example, acetic acid, propionic acid, butyric acid, or valeric acid. Propionic acid, and in particular acetic acid, are preferred. Suitable solubilizing agents are, for example, compounds of the following groups: I) alkali metal or ammonium salts of alkyl acids of 1 to 4 carbon atoms, II) low molecular weight amides, III) lactams or low molecular weight lactones, IV) alkanolic amines or reaction products of ethylene oxide and / or propylene oxide with alkanolic amines. The solubilizing agents of group I) are, in particular, the sodium, potassium, lithium or ammonium salts of acetic acid or propionic acid. Sodium and ammonium acetate are particularly preferred. The solubilizing agents of Group I), of course, do not have to be used in the form of the mentioned salts, but can also be prepared in the solutions from the corresponding bases and acids by neutralization. The low molecular weight acid amides are, in particular, formamide, and especially urea. Suitable solubilizing agents of Group III) are, for example, β-butyrolactam or e-caprolactone, but in particular β-butyrolactone, or especially e-caprolactam. The solubilizing agents of group IV) are, for example, dietanolic amine or trietanolic amine, but in particular the reaction products of 1 to 6 moles of ethylene oxide and / or propylene oxide with 1 mole of dietanolic amine or trietanolic amine. Particularly preferred compounds are those of the formula: N-l-CH2-CH2-O- (CH-CH-O) p-H] 3 I I (3) R8 R9 wherein: p is an integer from 1 to 6, and of the substituents R8 and R9, one is hydrogen and the other is hydrogen or methyl. Preferably, in the compounds of the formula (3), p is 1. The solubilizing agents of group I) are preferably present in an amount of 1 to 6 percent by weight, in particular 1 to 3 percent by weight , based on the weight of the solution. The solubilizing agents of groups II), III) and IV) are preferably present in an amount of 3 to 20 weight percent, in particular 6 to 15 weight percent, based on the weight of the solution. It is also possible to use mixtures of solubilizing agents of a group, or mixtures of solubilizing agents of different groups, for example, mixtures of ammonium acetate and urea. The alkyl acid of 1 to 4 carbon-carboxylic acids is preferably used in an amount of 3 to 20 weight percent, in particular 6 to 15 weight percent, based on the weight of the solution. Other additives which may be present in the concentrated solutions according to the invention are organic solvents, for example, dimethyl sulfoxide, N-methyl pyrrolidone, ethylene glycol, propylene glycol or glycerol, and boric acid. The concentrated aqueous solutions of group A) according to the invention can be prepared, for example, by filtering the dye solution obtained during the preparation of the dye, the subsequent addition of the alkyl acid of 1 to 4 carbon-carboxylic atoms, solubilizing agent, and if appropriate, other additives, with agitation, and finally the adjustment of the desired concentration with water. The concentrated aqueous solutions according to the invention of group B) do not comprise solubilizing agents, and therefore, can only comprise little alkali metal halide, since otherwise highly viscous solutions or those having inadequate storage stability are obtained. . As a result of the synthesis of the dyes of the Formula (1), which is normally carried out by reaction of cyanuric chloride with the corresponding amines at an alkaline pH, however, the dye solutions usually comprise considerable amounts of alkali metal halide, and consequently, they must be brought to an alkali metal halide content. less than 0.1 percent by weight, based on the total weight of the solution, by an appropriate process. This is achieved in a manner known per se, for example, by reverse osmosis, ultrafiltration or dialysis. These desalting processes are known, for example, from European Patent EP-A 0,059,782. The membranes used in these processes are also known, for example, from European Patent EP-A 0,061,424. The process conditions of this desalination are selected such that dye solutions are obtained which comprise less than 0.1 weight percent, preferably less than 0.07 weight percent, based on the total weight of the solution, of metal halides alkaline. The alkali metal halide of this Application should be understood to mean the lithium, sodium or potassium fluoride, chloride, bromide or iodide. The concentrated aqueous solutions according to the invention of group B) can, therefore, be prepared, for example, by filtration and desalting the dye solution obtained during the dye preparation, the subsequent addition of the alkyl acid from 1 to 4. carbon-carboxylic atoms, and if appropriate, other additives, with agitation, and finally the adjustment of the desired concentration with water. The concentrated aqueous coloring solutions according to the invention are stable for several weeks at storage temperatures of between 60 ° C and -20 ° C, and are suitable for dyeing paper, in which they produce attractive red shades of a high firmness to light with or without the use of a sizing agent and / or filler. The coloring solutions can be used by all the usual processes for the substantive dyes in the paper industry, in particular in the dyeing of pulp and in surface dyeing of paper for the grades, ready and without sizing, starting from bleached cellulose or not bleached of variable origin, such as sulphite cellulose and / or soft wood sulphate or hard wood, mechanical wood pulp or mixtures thereof with cellulose. The dyes of Formulas (l) and (2) are known, for example, from Japanese Patent Number JP-A-075, 924, or can be obtained in a manner analogous to the preparation process described therein. In the following examples, the parts are parts by weight, and the temperatures are declared in degrees Celsius.

Example 1: 120 parts of glacial acetic acid are added dropwise to 780 parts of an aqueous solution comprising 96 parts of the dye of the Formula: H5) 2 in the course of 50 minutes, with agitation. 120 parts of urea are added to the resulting thin liquid solution in the course of 10 minutes, with stirring, and the mixture is stirred for another 20 minutes. After the addition of 180 parts of water, the mixture is stirred for another 30 minutes. A thin liquid coloring solution is obtained which is stable to storage for several months, both at room temperature and at 4 ° C, at -20 ° C and at 60 ° C. This solution can be diluted as desired with water, without the occurrence of precipitates. A dyeing liquor containing 2 percent of the above coloring solution is stable to storage for several days at room temperature.

Example 2; 120 parts of glacial acetic acid are added dropwise to 780 parts of an aqueous solution comprising 96 parts of the dye of Example 1, over the course of 50 minutes, with stirring. 24 parts of ammonium acetate are added to the resulting thin liquid solution over the course of 10 minutes, with stirring, and the mixture is stirred for another 20 minutes. After the addition of 276 parts of water, the mixture is stirred for another 30 minutes. A thin liquid coloring solution is obtained which is stable to storage for several months, both at room temperature and at 4 ° C, at -20 ° C, and at 60 ° C. This solution can be diluted with water, as desired, without precipitates. A dyeing liquor containing 2 percent of the above coloring solution is stable to storage for several days at room temperature.

Example 3; 120 parts of glacial acetic acid are added dropwise to 780 parts of an aqueous solution comprising 96 parts of the dye of Example 1, over the course of 40 minutes, with stirring. 84 parts of the reaction product of 3 moles of propylene oxide with 1 mole of trietanolic amine are added to the resulting thin liquid solution over the course of 10 minutes, with stirring, and the mixture is stirred for another 20 minutes. After the addition of 240 parts of water, the mixture is stirred for another 30 minutes. A thin liquid coloring solution is obtained which is stable to storage for several months, both at room temperature and at 4 ° C, at -20 ° C, and at 60 ° C. This solution can be diluted with water as desired, without the occurrence of precipitates. A dyeing liquor containing 2 percent of the above coloring solution is stable to storage for several days at room temperature.

Example 4; 1 part of 48% acetic acid is added dropwise to 2.6 parts of an aqueous solution comprising 0. 32 parts of the dye of Example 1. 0.1 part of sodium acetate is added to the resulting thin liquid solution.

After the addition of 0.3 parts of water, the mixture is completely stirred. A thin liquid coloring solution is obtained which is stable to storage for several months, both at room temperature and at 4 ° C, at -20 ° C, and at 60 ° C. This solution can be diluted with water as desired, without the occurrence of precipitates. A dyeing liquor containing 2 percent of the above coloring solution is stable to storage for several days at room temperature.

Example 5; 1 part of 40 percent propionic acid is added to 2.6 parts of an aqueous solution comprising 0.32 parts of the dye of Example 1. 0.3 parts of urea are added to the resulting thin liquid solution. After the addition of 0.1 parts of water, the mixture is stirred vigorously. A thin liquid coloring solution is obtained which is stable to storage for several months, both at room temperature and at 4 ° C, at -20 ° C, and at 60 ° C. This solution can be diluted with water, as desired, without precipitates. A dyeing liquor containing 2 percent of the above coloring solution is stable to storage for several days at room temperature.

Example 6; 2662 parts of an aqueous solution having a pH of 9.7, comprising 256 parts of the dye described in Example 1, 40 parts of NaCl, and 26 parts of diethylaminopropyl amine, is brought to a pH of 12 by the addition of 40% NaOH. percent, and then desalted in a laboratory reverse osmosis unit under the following conditions: MPT 30 (MPS) membrane (polyethylene); approximately 50 ° C; 12 liters per minute feed; 25 bar; initial flow rate of 1425 liters / m2d. After 6 hours, 1234 parts of solution are obtained comprising 20.75 percent dye, and 0.04 percent NaCl. The solution no longer contains diethylaminopropyl amine. It is brought to a pH of 3.7, and to a dye content of 10 percent, by the dropwise addition of glacial acetic acid and the addition of water. A thin liquid coloring solution is obtained which is stable to storage for several months, both at room temperature and at 4 ° C, at -20 ° C, and at 60 ° C. This solution can be diluted with water, as desired, without precipitates. A dyeing liquor containing 2 percent of the above coloring solution is stable to storage for several days at room temperature.

Example 7: 70 parts of chemically bleached sulphite cellulose (softwood), and 30 parts of chemically bleached sulphite cellulose (hardwood), are beaten in 2000 parts of water in a blender. 2.5 parts of the coloring solution described in Example 1 are added to this pulp. After the 20 minute mixing time, paper is produced from this pulp. The absorbent paper obtained in this way is red. The dyeing shows a high firmness in light. The waste water is practically colorless.

Example 8i 3.0 parts of the coloring solution of Example 6 are dissolved in 100 parts of water, and the solution is added to 100 parts of chemically bleached sulphite cellulose, which has been beaten with 2000 parts of water in a blender. After a complete mixing for 15 minutes, the pulp is prepared with rosin size and aluminum sulfate in the usual manner. The paper produced from this pulp has a red hue with good properties of firmness to moisture and good firmness to light.

Claims

NOVELTY OF THE INVENTION
Having described the foregoing invention, it is considered as a novelty and, therefore, the content of the following is claimed as property:
CLAIMS 1. A concentrated aqueous coloring solution, which comprises A): a) at least 5 weight percent, based on the weight of the solution, of a red dye of the Formula: wherein: R and R 1 t independently of one another, are each hydrogen, Cl, methyl or methoxy, R 2 and R 3, independently of each other, are each hydrogen, methyl or methoxy, R 4 and R 5, independently of each other, are each hydrogen, or alkyl of 1 to 4 carbon atoms, A is an unbranched or branched alkylene radical, which may be interrupted by O, and R6 and R7 independently of each other, are each hydrogen or alkyl of 1 to 6 carbon atoms, or where R6 and R7 * together with the N atom bonded thereto form a substituted or unsubstituted 5, 6 or 7 membered ring, which may contain other heteroatoms, b) formic acid or an acid alkyl of 1 to 4 carbon-carboxylic atoms, c) a solubilizing agent, d) water, and if appropriate, e) other additives, or B) a) at least 5 weight percent, based on the weight of the solution, of a red dye of Formula (1), b) formic acid or an alkyl acid d and 1 to 4 carbon-carboxylic atoms, c) water, and if appropriate, d) other additives, with the proviso that the solutions do not comprise a solubilizing agent, and comprise less than 0.1 weight percent metal halide alkaline, based on the total weight of the solution. 2. A concentrated aqueous coloring solution according to claim 1, which comprises: a) at least 5 weight percent, based on the weight of the solution, of a red dye of the Formula: wherein: R and R1 (independently of each other, are each hydrogen, Cl, methyl or methoxy, R2 R3 'independently of each other, are each hydrogen, methyl or methoxy, R4 and R5, independently of each other, are each hydrogen, or alkyl of 1 to 4 carbon atoms, A is an unbranched or branched alkylene radical, which may be interrupted by O, and R6 and R7, independently of each other, are each hydrogen or alkyl of 1 to 6 carbon atoms, or where R6 and R7 / together with the N atom bonded to them, form a substituted or unsubstituted 5, 6 or 7-membered ring, which may contain other heteroatoms, b) formic acid or an acid alkyl of 1 to 4 carbon-carboxylic atoms, c) a solubilizing agent, d) water, and if appropriate, e) other additives. 3. A concentrated aqueous coloring solution according to claim 1 or 2, wherein R and Rx are each
H, methyl or methoxy. 4. A concentrated aqueous coloring solution according to claim 3, wherein R and Rj are each H.
5. A concentrated aqueous coloring solution according to any of claims 1 to 4, wherein R2 and R3 are each H.
6. A concentrated aqueous coloring solution according to any of claims 1 to 5, wherein R4 and R5 are each methyl or hydrogen.
7. A concentrated aqueous coloring solution according to any of claims 1 to 6, wherein A is a radical of the formula - (CH2) n-, wherein n is an integer from 2 to 6.
8. A coloring solution concentrated aqueous according to claim 7, wherein A is ethylene, normal propylene, isopropylene or normal butylene.
9. A concentrated aqueous coloring solution according to any of claims 1 to 8, wherein R6 and R7, independently of each other, are each unsubstituted alkyl of 1 to 4 carbon atoms.
10. A concentrated aqueous coloring solution according to claim 9, wherein R6 and R7 are identical, and are each methyl or ethyl.
11. A concentrated aqueous coloring solution according to any of claims 1 to 10, where the sulfo group is located in position m or in position p, in relation to the azo group.
12. A concentrated aqueous coloring solution according to any of claims 1 to 11, which comprises from 6 to 20 weight percent of dye, based on the weight of the solution.
13. A concentrated aqueous coloring solution according to claim 12, which comprises from 8 to 10 weight percent of dye, based on the weight of the solution.
14. A concentrated aqueous coloring solution according to any of claims 1 to 13, which comprises a dye of the Formula: wherein: m is 2, 3 or 4, and R6 and R7 are each alkyl of 1 to 2 carbon atoms.
15. A concentrated aqueous coloring solution according to any of claims 1 to 14, which comprises, as the solubilizing agent, a compound of one of the following groups: I) alkali metal or ammonium salts of alkyl acids of 1 to 4 carbon-carboxylic atoms, II) low molecular weight acid amides, III) low molecular weight lactams or lactones, IV) alkanolic amines or reaction products of ethylene oxide and / or propylene oxide with alkanolic amines.
16. A concentrated aqueous coloring solution according to claim 15, which comprises, as the solubilizing agent, sodium acetate or ammonium acetate, formamide, urea, e-caprolactam or a compound of the Formula: N - [- CH2-CH2-O- (CH-CH-O) p-H] 3 I I (3) R8 R9 wherein: p is an integer from 1 to 6, and of the substituents R 8 and R 9, one is hydrogen and the other is hydrogen or methyl.
17. A concentrated aqueous coloring solution according to claim 16, wherein p is 1.
18. A concentrated aqueous coloring solution according to any of claims 1 to 17, which comprises a solubilizing agent of group I) in an amount of 1 to 5 weight percent, based on the weight of the solution, or a solubilizing agent of groups II), III) or IV) in an amount of 3 to 20 weight percent, based on the weight of the solution .
19. A concentrated aqueous coloring solution according to claim 18, which comprises a solubilizing agent of group I) in an amount of 1 to 3 weight percent, based on the weight of the solution, or a solubilizing agent of the groups II), III) or IV) in an amount of 6 to 15 weight percent, based on the weight of the solution.
20. A concentrated aqueous coloring solution according to any of claims 1 to 17, which comprises an alkyl acid of 1 to 4 carbon-carboxylic atoms, in an amount of 3 to 20 weight percent, based on the weight of the solution.
21. A concentrated aqueous coloring solution according to claim 20, which comprises an alkyl acid of 1 to 4 carbon atoms, in an amount of 6 to 15 weight percent, based on the weight of the solution.
22. A process for the preparation of a concentrated aqueous solution of a dye of the Formula (1) according to claim 1, which comprises filtering, and if appropriate, desalting the dye suspension obtained during dye preparation, subsequently adding the alkyl acid of 1 to 4 carbon-carboxylic atoms, the solubilizing agent, and if appropriate, other additives, with stirring, and finally adjusting to the desired concentration with water.
23. The use of a concentrated aqueous coloring solution according to claim 1 for dyeing paper.