GB1597959A

GB1597959A - Monoazo dyes

Info

Publication number: GB1597959A
Application number: GB15283/77A
Authority: GB
Original assignee: Imperial Chemical Industries Ltd
Current assignee: Imperial Chemical Industries Ltd
Priority date: 1977-04-13
Filing date: 1977-04-13
Publication date: 1981-09-16
Also published as: FR2387268A1; JPS53128636A; ES468772A1; IT7822192A0; IT1095571B; BE865727A; DE2813981A1

Description

(54) MONOAZO DYES (71) We, IMPERIAL CHEMICAL INDUSTRIES LIMITED, Imperial Chemical House, Millbank, London, SW1P 3JF, a British Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: 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 each of R1 and R2, independently, represents hydrogen, lower alkyl, cyano, halogen, lower alkoxy, nitro, thiocyano, sulpho, -SO2R3 wherein R8 denotes lower alkyl,SO2NR9R1 wherein R9 and R10 independently denote hydrogen or lower alkyl or --COOR11 wherein R11 denotes hydrogen or lower alkyl; each of R3 and R4, independently, represents hydrogen, halogen, nitro, alkyl, alkoxy or sulpho; m and n have values of 1 or 2; R5 represents hydrogen, halogen, lower alkyl, lower alkoxy or acylamino; and R6 represents hydrogen, halogen, lower alkyl or lower alkoxy, with the proviso that only one of R1, R2, R3 and R4 is sulpho.

The expressions "lower alkyl" and "lower alkoxy" used herein mean alkyl and alkoxy groups containing one to four carbon atoms.

Acylamino groups which may be represented by Rs include, in particular, groups of the formulae -NHCOQ1 and -NHSO2Q2 wherein Q1 represents hydrogen, alkyl (especially lower alkyl), aryl or aminoalkyl and Q2 represents optionally substituted lower alkyl or aryl.

It is preferred that either R1 or R2 is sulpho.

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

and coupling the resulting diazo compound with a tertiary amine of the formula:

wherein R1, R2, R3, R', Ra, R6, m and n have the meanings given above, the primary amine and the tertiary amine together containing only one sulphonic acid group.

Suitable primary amines for use in making the dyes include 2-amino-1,3-benzthiazole, 4-, 5-, 6- or 7-chloro-2-amino-1,3-benzthiazole, 4,6-dichloro- (or dibromo)2-amino-1,3-benzthiazole, 6-methoxy-2-amino-1,3 -benzthiazole, 6-thiocyano-2-amino 1,3 -benzthiazole, 6-nitro-2-amino-1,3-benzthiazole, 6-cyano-2-amino-1,3-benzthiazole, 6-methylsulphonyl-2-amino-1,3 -benzthiazole, 6-ethylsulphonyl-2-amino-1,3-benzthiazole, 2-amino-1,3-benzthiazole-6-sulphonic acid methylamide, 2-amino-1,3-benzthiazole-6-sulphonic acid diethylamide, 2-amino-1,3-benzthiazole-4-, 5-, 6- or 7sulphonic acid, 6-chloro-2-amino-1,3-benzthiazole-4-, or 5-sulphonic acid, 6-methoxy2-amino-1,3-benzthiazole-4- or 5-sulphonic acid and 6-methyl-2-amino-1,3-benzthi azole4- or 5-sulphonic acid.The preferred diazo component is 2-amino-l,3-benz- thiazole-5-sulphonic acid.

Examples of suitable coupling components include N,N-dibenzylaniline, N,Ndibenzyl-m-toluidine, N,N-dibenzyl-m-anisidine, N,N-dibenzyl-m-aminoacetanilide, N,N-dibenzyl-m-aminobenzanilide, N,N-dibenzyl-m-chloroaniline, N,N-dibenzyl-mbromoaniline, N,N-di(o-, m- or p-chlorobenzyl)aniline, N,N-di(o-, m- or p-nitrobenzyl)aniline, N,N-di(o-, m- or p-methylbenzyl)aniline, N,N-di(o-, m- or p-methoxybenzyl)aniline and N-benzyl-N- (3 -sulphobenzyl ) aniline.

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, nylon 6 and nylon 11, using any of the general methods known for the application of acid dyes to such materials. The dyes provide orange to red shades having a high degree of fastness to wet treatments and to light.

The invention is illustrated but not limited by the following Examples in which all parts and percentages are by weight Example 1.

0.8 Part of sodium nitrite is dissolved in 10 parts of 98% sulphuric acid at 2535"C and the solution is cooled to 000. 2.3 parts of 2-amino-1,3-benzthiazole-5- sulphonic acid are added with vigorous stirring and the temperature is maintained at 0 C during the addition of 12.5 parts of water. The mixture is stirred at 0 C for a further 2 hours after which the excess nitrous acid present is destroyed by the addition of sulphamic acid.

The diazonium salt suspension is then added, with stirring, to an ice cold mixture of 2.73 parts of finely divided N,N-dibenzylaniline and 100 parts of water and stirring is continued for a further 20 hours. The precipitated crystalline dyestuff, which is in the form of the free sniphonic acid, is collected by filtration, washed with water and converted to its sodium salt by treatment with sodium hydroxide. It dyes synthetic polyamide fibres or fabrics from a neutral or weakly acidic dyebath in clear red shades having good fastness to light and excellent fastness to wet treatments.

The 2-amino-1,3-benzthiazole-5-sulphonic acid used in this Example is prepared as follows: 24 Parts of 4-amino-3-nitrobenzene sulphonic acid sodium salt are dissolved in 125 parts of 1 molar sulphuric acid with stirring and the solution is cooled to OOC and diazotised by the slow addition of 2 molar sodium nitrite solution. 15 Parts of sodium acetate are then added and the mixture is added to a stirred solution of 15.2 parts of ammonium thiocyanate and 0.5 part of cuprous thiocyanate dissolved in 200 parts of water. After 2 hours the evolution of nitrogen has ceased and no diazonium salt can be detected in the reaction mixture.The whole mixture is then added to a mixture of 50 parts of iron filings, 100 parts of water and 1 part of 36% hydrochloric acid which has previously been stirred and heated at 950C for 30 minutes, and stirring at 90-950C is continued for 2 hours. The mixture is then made alkaline by the addition of 4 parts of sodium carbonate and filtered. The clear filtrates are acidified by the addition of hydrochloric acid and the precipitate thus formed is collected by filtration, washed with water and dried at 1200 C.

Example 2.

The N,N-dibenzylanliine used in Example 1 is replaced by 2.87 parts of N,Ndibenzyl-m-toluidine whereupon a dyestuff is obtained which dyes synthetic polyamide fibres or fabrics in bluish-red shades of similar high fastness.

If, in Example 1, the diazo and coupling components are replaced by the compounds indicated in the table, further dyestuffs which dye polyamide in orange to red shades are obtained.

Ex. Diazo Component Coupling Component 3 2-amino-1,3-benzthiazole-5- N,N-dibenzyl-m-anisidine sulphonic acid N,N-dibenzyl-m-aminobenzanilide 4 " N,N-dibenzyl-m-aminobenzanilide 5 " N, N-di b en zy l-m-ch loroani line 6 " N,N-dibenzy l-2-methoxy-5-methyl- aniline 7 " N,N-dibenzy l-2-methoxy-5-acetyl- aminoaniline 8 2-amino-1,3-benzthiazole-6- N,N-dibenzylaniline sulphonic acid 9 " N,NZibenzy!-m-toluidine 10 " N,N-dibenzyl-rn-aminobenzanilide 11 2-amino-6-chloro-l ,3-benzthiazole- N,N-dibenzy l-m-toluidine 5-sulphonic acid 12 2-amino6-methoxy-1,3-benzthiazole- N,N-dibenzyl-m-toluidine 5-sulphonic acid 13 2-amino-6-thiocyano-1,3-benz- N,N-dibenzyl-m-toluidine thiazole-5-sulphonic acid 14 2-amino-l, 3-benzthiazole 3-(N-benzy l-N-3-methy Iphenyl aminomethyl)-benzene sulphonic acid 15 2-amino-6-chloro-1,3 -benzthiazole " 16 2-amino-6-bromo-l ,3-benzthiazole 17 2-amino-6-methyl-l,3-benzthiazole 18 2-amino-6-methoxy-1,3-benzthiazole 19 2-amino-6-cy ano-1,3-benzthiazole " 20 2-amino-6-thiocyano-1,3-benzthiazole 21 2-amino-6-methylsulphonyl-1,3-benz- " thiazole 22 2-amino-6-(N ,N-dimethy Isulpha moyl)-1,3-benzthiazole 23 2-amino-6-nitro-1,3-benzthiazole 24 2-amino-4,6-dichloro-1.3-benz thiazole

Ex. Diazo Component Coupling Component 25 2-amino-1,3-benzthiazole-5- N,N-bis(2-chlorophenylmethyl) sulphonic acid aniline 26 " N,N-bis (2-chloropheny lme thy 1) -m- toluidine 27 " N,N-bis (4-chlorophenylmethy 1) -m- toluidine 28 " N,N-bis(4-methy Ipheny Ime thy l)-m- toluidine 29 2-amino-5-(N ,N-dimethy Isulpha- 3-(N-benzy l-N-3-methy lpheny I- moyl)1 ,3-benzthiazole aminomethyl)benz ene sulphonic acid

The 3-(N-benzyl-N-3-methylphenylaminomethyl)benzene sulphonic acid used in some of the Examples is obtained by the reaction of benzyl chloride with 3-(N-3methylphenylaminomethyl)benzene sulpohonic acid which is itself obtained by sulphonation of N-benzyl-m-toluidine.

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

wherein each of R1 and R2, independently, represents hydrogen, lower alkyl, cyano, halogen, lower alkoxy, nitro, thiocyano, sulpho, -SO2R8 wherein R8 denotes lower alkyl, -SO2NR9R'0 wherein R9 and R10 independently denote hydrogen or lower alkyl or -C0OR11 wherein R11 denotes hydrogen or lower alkyl; each of R3 and R4, independently, represents hydrogen, halogen, nitro, alkyl, alkoxy or sulpho; m and n have values of 1 or 2; R5 represents hydrogen, halogen, lower alkyl, lower alkoxy or acylamino; and R6 represents hydrogen, halogen, lower alkyl or lower alkoxy, with the proviso that only one of R1, R2, R3 and R4 is sulpho, the expressions "lower aLkyl" and "lower alkoxy" meaning alkyl and alkoxy groups containing one to four carbon atoms.

2. A water-soluble monoazo dye as claimed in claim 1 wherein R1 and R2 is sulpho.

3. A water-soluble monoazo dye as claimed in claim 1 and specifically identified in Example 1 or Example 2.

4. A water-soluble monoazo dye as claimed in claim 1 and specifically identified in any one of Examples 3 to 29.

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:

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. Ex. Diazo Component Coupling Component 25 2-amino-1,3-benzthiazole-5- N,N-bis(2-chlorophenylmethyl) sulphonic acid aniline 26 " N,N-bis (2-chloropheny lme thy 1) -m- toluidine 27 " N,N-bis (4-chlorophenylmethy 1) -m- toluidine 28 " N,N-bis(4-methy Ipheny Ime thy l)-m- toluidine 29 2-amino-5-(N ,N-dimethy Isulpha- 3-(N-benzy l-N-3-methy lpheny I- moyl)1 ,3-benzthiazole aminomethyl)benz ene sulphonic acid The 3-(N-benzyl-N-3-methylphenylaminomethyl)benzene sulphonic acid used in some of the Examples is obtained by the reaction of benzyl chloride with 3-(N-3methylphenylaminomethyl)benzene sulpohonic acid which is itself obtained by sulphonation of N-benzyl-m-toluidine. WHAT WE CLAIM IS:

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

and coupling the resulting diazo compound with a tertiary amine of the formula:

wherein R1, R2, R9, R4, R5, RS, m and n have the meanings given in claim 1, the primary amine and the tertiary amine together containing only one sulphonic acid group.

6. A method as claimed in claim 5 wherein the primary amine is 2-amino-1,3benzthiazole-5-sulphonic acid.

7. A method as claimed in claim 5 conducted substantially as hereinbefore described with reference to any one of the foregoing Examples.

8. A water-soluble monoazo dye whenever prepared by a method claimed in any one of daims 5 to 7.

9. 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 to 4 and 8.

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