GB2074599A

GB2074599A - Monoazo Dyes

Info

Publication number: GB2074599A
Application number: GB8104729A
Authority: GB
Original assignee: Imperial Chemical Industries Ltd
Current assignee: Imperial Chemical Industries Ltd
Priority date: 1980-04-23
Filing date: 1981-02-16
Publication date: 1981-11-04

Abstract

Water-soluble monoazo dyes which, in the form of the free acids, have the formula: <IMAGE> wherein X represents -O- or -NH-, R represents an alkyl, aryl or -NH2 radical and rings A and B may carry other substituents. The dyes give yellow and orange shades on natural and synthetic polyamide textiles.

Description

SPECIFICATION Monoazo Dyes This invention relates to monoazo dyes and their application to textile materials.

According to the invention, there are provided water-soluble monoazo dyes which, in the form of the free acids, have the formula:

wherein X represents -0- or -NH-, R represents an alkyl, aryl or -NH2 radical and rings A and B may carry other substituents.

Other substituents which may be present on rings A and B in addition to those shown include halogen atoms, especially chlorine and bromine, and alkyl and alkoxy radicals.

The alkyl radicals which R may represent preferably contain from one to eight carbon atoms and the aryl radicals are preferably phenyl or substituted phenyl radicals.

Particularly valuable dyes within the scope of Formula I have the formula:

wherein R has the meaning given above, each of R' and R2, independently, represents hydrogen or halogen, especially chlorine, and Z represents hydrogen or alkyl.

Another useful class of dyes within the scope of Formula I has the formula:

wherein ring A may be further substituted and ring B carries at least one halogen, especially chlorine, atom.

The dyes of the invention may be prepared by diazotising a primary amine of the formula:

and coupling the resulting diazo compound with a coupling component of the formula:

the symbols A, B, X and R having the meanings given above.

Examples of primary amines which can be used in making the dyes include 4 (phenoxysulphonyl)aniline, 2-chloro-4-(phenoxysulphonyl)aniline, 2,5-dichloro-4 (phenoxysulphonyl)aniline, 4-(4'-t-butylphenoxysulphonyl)aniline), 3-chloro-4aminobenzenesulphonanilide and 3,6-dichloro-4-aminobenzenesulphonalide.

Examples of coupling components for use in making the dyes include 5-acetylaminoaniline-2sulphonic acid, 5-benzoylaminoaniline-2-sulphonic acid and 5-ureidoaniline-2-sulphonic acid.

The reactions leading to the formation of the dyes of the invention may be performed using conditions that have been fully described in the prior art for such reactions. Similarly, the dyes may be isolated by known methods and, as in the case of other dyes containing sulphonic acid groups, it is often convenient to isolate and use the dyes in the form of their water-soluble salts, particularly their alkali metal or ammonium salts and especially sodium salts. It is to be understood that the invention relates to both the free acids and their salts.

The dyes of the invention are suitable for applying to polyamide textile materials such as wool and silk but especially to synthetic polyamide textile materials, for example nylon 66 and nylon 6, using any of the general methods known for the application of acid dyes to such materials. The dyes provide yellow to orange shades having a high degree of fastness to wet treatments and to light.

The dyes are also valuable in providing colorations on polyamide fibres exhibiting little or no phototropism. In this respect the dyes of Formulae II and Ill are particularly useful.

The invention is illustrated but not limited by the following examples, in which all parts and percentages are by weight.

Example 1 A solution of 24.9 parts (0.1 mol; 100% strength) of 4-(phenoxysulphonyl)aniline in 200 parts of glacial acetic acid and 50 parts of 35% hydrochloric acid is diazotised at 0--50C with 7 parts of sodium nitrite in 50 parts of water. After a further 30 minutes the excess nitrous acid is removed and the diazonium salt solution is added to a solution of 25 parts (0.1 mol; 92% strength) of 5acetylaminoaniline-2-sulphonic acid in 500 parts of water and 10 parts of 32% sodium hydroxide solution at 0--5 OC. Stirring at 0--5 OC and 200C is continued for 2 hours and 16 hours respectively and the monoazo dye is collected and washed with water.Conversion of the product to its sodium salt is effected by dissolving in 500 parts of water and adjusting the pH to 9 with sodium hydroxide solution and after adding 50 parts of sodium chloride it is isolated and dried. The dyestuff obtained corresponds to the formula:

When applied to nylon under neutral or slightly acidic conditions a non-phototropic bright reddish yellow shade is obtained having good fastness to washing and to light.

Example 2 A solution of 28.3 parts (0.1 mol; 100% strength) of 3-chloro-4-aminobenzenesulphonanilide in 200 parts of glacial acetic acid and 50 parts of 35% hydrochloric acid is diazotised at 0--5 OC with 7 parts of sodium nitrite in 50 parts of water and, after removing the excess nitrous acid, the diazonium salt solution is added to a solution of 23.1 parts of 5-ureidoaniline-2-sulphonic acid (0.1 mol; 100% strength) in 500 parts of water at 0--5 OC and pH 5. Stirring at 0--5 OC and 200C is continued for 3 hours and 16 hours respectively and the monoazo dye is collected. The product is converted to its sodium salt and isolated by the procedure described in Example 1.The dyestuff obtained corresponds to the formula:

When applied to nylon under neutral or slightly acidic conditions a non-phototropic orange shade is obtained having good fastness to washing and to light.

Further examples of dyes of the invention are prepared in a similar manner by diazotising the amine listed in the second column of the table below and coupling onto the coupling component listed in the third column. When applied to nylon under neutral or slightly acidic conditions the nonphototropic shades listed in the fourth column are obtained.

Coupling Ex. - Amine Component Shade 3 4-(phenoxysulphonyl) 5-ureidoaniline-2- Reddish aniline sulphonic acid yellow 4 ,, 5-benzoylaminoaniline 2-sulphonic acid 5 2,5-dichloro-4- " Orange (phenoxysulphonyl) aniline

Coupling Ex. Amine Amine Component Shade 6 ,, 5-acetylaminoanilin 2-sulphonic acid 7 ,, 5-ureidoaniline-2 sulphonic acid 8 4-(4'-nonyl 5-acetylaminoaniline- Reddish phenoxysulphonyl) 2-sulphonic acid yellow aniline 9 4-(4'-octyl phenoxysulphonyl) aniline 10 4-(4'-t-butyl phenoxysulphonyl) aniline 11 4-(3'-t-butyl " " phenoxysulphonyl) aniline 12 2-chloro-4- ,, Orange (phenoxysulphonyl) aniline 13 ,, 5-ureidoaniline-2 sulphonic acid 14 5-chloro-4- 5-acetylaminoaniline Orange (phenoxysulphonyl) 2-sulphonic acid aniline 15 3,6-dichloro-4- aminobenzene sulphonanilide 16 " 5-benzoylaminoaniline 2-sulphonic acid 17 .. 5-ureidoaniline-2 sulphonic acid

Claims

1. A water-soluble monoazo dye which, in the form of the free acid, has the formula:

2. A water-soluble monoazo dye according to claim 1 having the formula:

wherein R has the meaning given in claim 1, each of R1 and R2 independently, represents hydrogen or halogen and Z represents hydrogen or alkyl.

3. A water-soluble monoazo dye according to claim 1 having the formula:

wherein ring A may be further substituted and ring B carries at least one halogen atom.

4. A water-soluble monoazo dye according to claim 1 and specifically identified herein.

5. A method for the preparation of a water-soluble monoazo dye as defined in claim 1 which comprises diazotising a primary amine of the formula:

the symbols A, B, X and R having the meanings given in claim 1.

6. A method according to claim 5 conducted substantially as hereinbefore described with reference to any one of the foregoing Examples.

7. A water-soluble monoazo dye whenever prepared by a method claimed in claim 5 or claim 6.

8. A process for the coloration of polyamide textile materials which comprises applying thereto a water-soluble monoazo dye as claimed in any one of claims 1-4 and 7.

9. Polyamide textile materials whenever coloured by the process claimed in claim 8.