GB2074597A

GB2074597A - Basic Azo Dyestuffs

Info

Publication number: GB2074597A
Application number: GB8103435A
Authority: GB
Original assignee: Imperial Chemical Industries Ltd
Current assignee: Imperial Chemical Industries Ltd
Priority date: 1980-04-21
Filing date: 1981-02-04
Publication date: 1981-11-04

Abstract

Mid-blue cationic azo dyes for polyacrylonitrile are derived from 2- amino-cycloalkyl thiazole diazo components and para coupling amines. They have the formula (I> <IMAGE> wherein R is optionally substituted alkyl, alkenyl, cycloalkyl or aralkyl, R<1> is hydrogen, optionally substituted alkyl, cycloalkyl, aralkyl or aryl, or completes a 5- or 6-membered ring by joining to ring B, R<2> is hydrogen or optionally substituted alkyl, n is an integer which is 2, 3, 4 or 5, ring B is optionally substituted and A<(-)> is an anion.

Description

SPECIFICATION Basic Azo Dyestuffs This invention relates to new water soluble azo dyestuffs and to their manufacture and use for the colouration of synthetic polymeric materials especially polymers and copolymers of acrylonitrile and dicyanoethylene and also acid modified polyesters and polyamides.

According to the present invention we provide azo dyestuffs devoid of carboxylic acid and sulphonic acid groups and of formula (I)

wherein R is optionally substituted alkyl, alkenyl, cycloalkyl or aralkyl, R is hydrogen, optionally substituted alkyl, cycloalkyl, aralkyl or aryl, or completes a 5- or 6-membered ring by joining to ring B, R2 is hydrogen or optionally substituted alkyl, n is an integer which is 2, 3, 4, or 5, ring B is optionally substituted and As is an anion.

The ring B may be substituted with one or more of the substituents normally to be found in dyestuff molecules. In particular, it is substituted in either or both of the 2 and 5 positions relative to the amino group, being derived from coupling components of formula (II)

wherein R1 and R2 are as hereinbefore defined, R3 is lower alkyl such as methyl, ethyl, propyl or butyl, lower alkoxy such as methoxy and ethoxy or halogen such as chlorine or bromine, and R4 is lower alkyl such as methyl, ethyl, propyl or butyl, lower alkoxy such as methoxy, ethoxy, propoxy or butoxy, halogen such as chlorine or brimine, carbalkoxy such as methoxycarbonyl and ethoxycarbonyl, acyl such as methyl-, ethyl- and phenylcarbonyl, and methyl-, ethyl- and phenyl-sulphonyl, nitro, cyano trifluoromethyl, thiocyano, acylamino such as formamide, acetylamino, propionylamino, phenyl-, ethyland methyl-sulphonylamino, sulphonamido, alkylsulphonamido such as methyl-, ethyl-, dimethyl and diethylsulphonamido, carbonamido and alkyl-carbonamido such as methyl-, ethyl-, diethyl- and dimethylcarbonamido, aryl acid amides such as phenylcarbamoyl and phenylsulphamoyl and ureido.

Preferred examples of R3 include methyl, ethyl, methoxy, ethoxy and chloro. Preferred examples of R4 include methyl, ethyl, methoxy, ethoxy, formamido, acetylamino, propionylamino, ureido, chloro and bromo.

Examples of R are methyl, ethyl, propyl, butyl, allyl, 2-hydroxyethyl, 1-chloro-2-hydroxypropyl, benzyl, 4-methylbenzyl, 2-carbamoyl ethyl, 2-carbamoyl-2-methylethyl, 2-chloroethyl, 2-bromoethyl, 2-acetoxyethyl, cyclohexyl, phenylethyl, methoxyethyl and methoxycarbonylethyl. Most conveniently R is methyl.

Examples of R1 are methyl, ethyl, propyl, butyl, phenyl, tolyl, lower alkoxyphenyl such as methoxy and ethoxy phenyl, hydroxy lower alkyl such as 2-hydroxyethyl, 2- and 3-hydroxypropyl and 3-chloro2-hydroxypropyl, lower alkoxy lower alkyl such as 2-(methoxy and ethoxy)ethyl and 3-methoxypropyl, cyano lower alkyl such as 2-cyanoethyl, aryl lower alkyl such as benzyl and p-phenylethyl, acyloxy lower alkyl such as 2-acetoxyethyl, lower alkoxycarbonyl lower alkyl such as 2-methoxycarbonylethyl, hydroxy lower alkoxy lower alkyl such as 2-(2'-hydroxyethoxy)ethyl, lower alkoxy lower alkoxycarbonyl lower alkyl such as 2-(2'-methoxyethoxycarbonyl)ethyl, 2-carbamoylethyl, cycloalkyl such as cyclo hexyl, hydroxyaryloxy lower alkyl such as hydroxyphenoxyethyl and cycloalkoxy lower alkyl such as cyclohexyloxyethyl. R1 may contain a cationic group and may be, for example, pyridinium or picolinium lower alkyl, or tri lower alkyl ammonium lower alkyl.

Examples of coupling components in which R' forms a 6-membered ring by joining to ring B are the optionally substituted tetahydroquinolines described in our UK Patent Specification No. 1,508,500 and optionally substituted benz morpholines. Examples of coupling components in which R1 forms a 5 membered ring by joining to ring B are the optionally substituted indoles also described in our UK Patent Specification No. 1,508,500.

Examples of R2 are those described for R' when R' is optionally substituted alkyl.

The anion Ao may be any of the organic or inorganic based anions well known to technologists in the field of cationic dyes. Most importantly they include iodide, chloride, bisulphate, tetrachlorozincate, acetate and methyl sulphate. In those cases where the anion is polyvalent the dyestuffs will contain a corresponding molar proportion of the cationic part of the dye.

Of particular interest to us are the dyestuffs of formula (I) in which R is methyl, R1 is hydrogen, optionally substituted lower alkyl, cyclohexyl, benzyl or optionally substituted phenyl, R2 is optionally substituted lower alkyl, n is an integer which is 3 or 4, ring B is optionally substituted with one or more substituents selected from the group comprising methyl, methoxy, bromo, thiomethoxy and acetylamino and As is an anion.

When we use the term "lower" in relation to alkyl or an alkyl-containing group we mean that the alkyl moiety has from 1 to 4 carbon atoms.

In a further aspect of our invention we provide a process for the manufacture of a dyestuff of formula (I) which comprises quaternising a compound of formula (Ill)

with a compound RZ, wherein R, R', R2, n and B have the meanings hereinbefore defined and Z is a group capable of forming an anion, and if the anion of Z is not the same as the anion As, replacing the anion of Z by Ao by metathesis.

Suitable quaternising agents RZ include those alkylating agents and other quaternising agents well known in the art and described in, for example, UK Patent Specification No. 1,508,580. Suitable methods by which quaternisation can be carried out are also described in that specification.

Compounds of formula (Ill) are made by coupling a diazotised amine of formula (IV)

with a coupling component of formula (V)

wherein n, B, R1 and R2 have the meanings hereinbefore defined.

The amine is diazotised in the usual way using mineral acid and sodium nitrite or nitrosyl sulphamic acid in concentrated sulphuric acid. Coupling is carried out in neutral to acid medium, for example, in acetic acid.

Amines for use in the invention are those of formula (IV) in which n is 2, 3, 4 or 5.

Suitable coupling components are, for example, N-ethyl-N-,-hydroxyethylaniline, N-ethyl-N-,B-hydroxyethyl-3-methyianiline, N-ethyi-N-p-pyridiniumethylaniline, N,N-diethylaniline, N,N-diethyl-3-methylaniline, N,N-diethyl-3-methoxyaniline, . N-ethyl-N-y-chloro-,6-hydroxypropyl-3-methylaniline, N,N-diethyl-3-acetylaminoaniline, N-methyl benzmorpholine, N-methyl-N-p-tolylaniline, N-methyl-N-p-tolyl-3-methoxyaniline, N-methyl-N-phenylaniline, N-methyl-N-p-methoxyphenylaniline, N-methyl-N-p-ethoxyphenylaniline, and N-methyl-2,2,4-trimethyltetrahydroquinoline.

The dyestuffs of the invention may be used to colour polymeric materials by application from an aqueous bath.

They give valuable bright mid-blue shades of high tinctorial strength.

Dyes from 2-aminothiazole itself tend to be violet and those coupled onto dialkylanilines have high compatibility values (CV). We have found that incorporation of a cycloalkyl moiety in 2amionothiazole gives an unexpected bathochromic shift to mid-blue and at the same time decreases the CV to a more desirable level of about 3 as assessed by the method for the determination of Compatibility Values described in the Journal of the Society of Dyers and Colourists, Volume 87, No. 2, page 60 (1 971). The importance of Compatibility Values is discussed, for example, in our UK Patent Specification No. 2,021,61 6.

In particular the dyestuffs of the invention are valuable for dyeing polyacrylonitrile materials and may be applied to polyacrylonitrile materials from acid, neutral or slightly alkaline dyebaths (i.e. pH from 3-8) at temperatures between 40-1 200C and preferably between 80-1 200C or by printing techniques using thickened print pastes. Dyeings of good properties are obtained. Generally the dyes exhibit better heat fastness than Basic Blue 41.

The dyestuffs of the invention may be used for the colouration of polymeric textile materials, particularly polymers and copolymers of acrylonitrile, by the wet transfer printing process. In this process a support, such as paper is printed with an ink containing a dyestuff, and printed support is placed in contact with a textile material and the whole then subjected to heat pressure under humid or wet conditions and the dyestuff transferred to the textile material.

The invention is illustrated, but not limited, by the following Examples in which all parts and percentages are by weight unless otherwise stated. Where parts are by volume, the relationship between weight and volume is the same as that between gram and millilitre.

Example 1 1.54 parts of 2-aminocyclohexathiazole, obtained by reacting thiourea with a-bromo- or cg-chloro- cyclohexanone, is dissolved in 25 parts by volume of glacial acetic acid. Concentrated hydrochloric acid (2 parts by volume) is added and the stirred solution cooled to between 5 and 100C. 5 Parts by volume of 2N sodium nitrite solution is added and the resulting diazo solution is stirred for 2 hours to complete the diazotisation.

The diazo solution is poured into a solution of 1.8 parts of N-ethyl-N-p-hydroxyethylaniline in 50 parts by volume of acetone at between 0 and 50C. After stirring at this temperature for 2 hours, the coupling mixture is poured into 200 parts of water and neutralised by the addition of sodium acetate.

The resulting solution is stirred for a sufficient period of time to allow the acetone to evaporate.

A tarry residue is filtered off, dissolved in chloroform, dried over magnesium sulphate and then filtered to remove the insoluble material.

0.5 Parts of magnesium oxide and 2 parts by volume of dimethyl sulphate are added to the filtrate and the mixture stirred at ambient temperature for 3 hours. Analysis by thin layer chromatography indicates complete reaction. After filtering the mixture through "Hyflo Supercel" filter aid to remove the inorganic material, the chloroform is removed by evaporation and the residual solid dissolved in hot water. The dyestuff of formula (Vl) is precipitated from solution by the addition of sodium iodide, and filtered and dried at 400C.

It dyes Orlon polyacrylonitrile an attractive mid-blue shade, similar to that obtained from Basic Blue 41. The dyed fabric has food fastness properties, particularly to heat treatments such as steam pleating and dry heat setting. The dye also displays good resistance to hydrolysis in dyebaths.

Examples 2 to 17 Dyestuffs of formula (VII) are prepared in similar manner to that of Example 1 using the appropriate diazo and coupling components and precipitating agent.

The definitions of E, n and Ao are given in the table for each example together with the shade that the dyestuff dyes polyacrylonitrile (PAN).

Shade Ex. n E Anion wade on PAN CII ZnC1 20 2 3 /25 / 2 5 ZnCl 24;) Mid blue C C2H40H 4 OH 2 4 CII 3 3 2 /=-\ rl L5 C H OH 24 4 2 G H5 6 ZnC1429 | Blue I\/N\%114 5 3 II II II 5 3 ll ll ll

Ex. n E Anion Shade on PAN 6 3 ~ Gl < 3 Mid r/2 blue . a = S 7 --N(C H,) oo II 232 CII.

'I Reddish < ( 2 5)2 blue OCH 3 CII Znt;l Mid 9 3 C2Hs '/"25 2 N // ,N \ blue 'CK,CHCK,C1 CII. LI L 3) OH 10 3 < l Blue ?o,--N I( Blue r NHCOCH 3 11 3 ~ ll Greenish blue L3

Shade Ex. | n | E ~ Anion SOhapAN 12 3 CII CH3 C1E3 Blue NMcH3 OCH 3 13 3 CII znCl at Greenish (N' blue 14 3 CII .

0CII 3 15 3 CH3 II II OC II 25 16 3 6) CH3 - g CH, i3 -7 1/ 17 3 ĭ;3CII3

Claims

1. Azo dyestuffs devoid of carboxylic acid and sulphonic acid groups and of formula (I)

wherein R is optionally substituted alkyl, alkenyl, cycloalkyl or aralkyl, R1 is hydrogen, optionally substituted alkyl, cycloalkyl, aralkyl or aryl, or completes a 5-or 6-membered ring by joining to ring B, R2 is hydrogen or optionally substituted alkyl, n is an integer which is 2, 3, 4, or 5, ring B is optionally substituted and Ae is an anion.

2. Azo dyestuffs according to claim 1 in which R is methyl, R' is hydrogen, optionally substituted lower alkyl, cyclohexyl, benzyl or optionally substituted phenyl, R2 is optionally substituted lower alkyl, n is an integer which is 3 or 4, ring B is optionally substituted with one or more substituents selected from the group comprising methyl, methoxy, bromo, thiomethoxy and acetylamino and As is an anion.

3. Azo dyestuffs according to claim 1 substantially as herein described with reference to any one of Examples 1 to 17.

4. Process for the manufacture of a dyestuff according to claim 1 which comprises quaternising a compound of formula (III)

with a compound RZ, wherein R, R', R2, n and B have the meanings given in claim 1 and Z is a group capable of forming an anion, and if the anion of Z is not the same as the anion Ao, replacing the anion of Z by Ao by metathesis.

5. Process according to claim 4 substantially as herein described with reference to any one of Examples 1 to 17.

6. Process for dyeing polyacrylonitrile material by treating the material with a dyestuff according to any one of claims 1 to 3.

7. Material dyed by a process according to claim 6.