GB2330841A - Di- & tri-azinylamino monoazo dyes for use in ink jet inks - Google Patents

Abstract

Monoazo compounds of the Formula (1) and salts thereof: wherein R<SP>1</SP>, A, L<SP>1</SP>, Z, W, j, k and m are as defined in the description. Also claimed are inks containing a compound of the Formula (1), an ink jet printing process using the inks and an ink jet printer cartridge containing an ink containing a compound of the Formula (1). Such inks may be used to print paper, an overhead projection slide or a textile material. In Formula (1): A is N, C-CI, C-CN or C-NO 2 ; each W independently is a substituent other than carboxy, sulpho, sulphatoethylsulphonyl or vinyl sulphone; L<SP>1</SP> is -SR<SP>3</SP>, -OR<SP>4</SP> or -NR<SP>5</SP>R<SP>6</SP>; Z is -O-, -S- or -NR<SP>2</SP>-; R<SP>1</SP>, R<SP>2</SP>, R<SP>3</SP> and R<SP>5</SP> are each independently H or optionally substituted alkyl; R<SP>4</SP> is substituted alkyl; R<SP>6</SP> is a group of the formula -(C a H 2a O) p (C b H 2b O) q X, or alkyl optionally substituted by carboxy, sulpho, alkoxy, hydroxy(alkoxy), a group represented by T or a 5- or 6- membered heterocyclic group; or R<SP>5</SP> and R<SP>6</SP> together with the nitrogen to which they are attached form an optionally substituted five or six membered ring; (57) continued overleaf T is an optionally substituted amino group; X is hydrogen or alkyl; a and b are different and from 1 to 6; p is from 1 to 4; q is from 0 to 3; j, k and m each independently is 0 to 5; and (j+k+m) is from 1 to 5; with the provisos that: (a) when j = 0 and m = 0, then at least one W is a group represented by T or is a group substituted by T; and (b) when j = 0, k = 0 and m = 1, than R<SP>5</SP> and R<SP>6</SP> together with the nitrogen to which they are attached do not form a morpholine ring.

Description

COMPOUNDS This invention relates to dyes, to inks and to their use in ink jet printing ("IJP). IJP is a non-impact printing technique in which droplets of ink are ejected through a fine nozzle onto a substrate without bringing the nozzle into contact with the substrate.

There are many demanding performance requirements for dyes and inks used in IJP. For example they desirably provide sharp, non-feathered images having good water-fastness, light-fastness and optical density. The inks are often required to dry quickly when applied to a substrate to prevent smudging, but they should not form a crust over the tip of an ink jet nozzle because this will stop the printer from working. The inks should also be stable to storage over time without decomposing or forming a precipitate which could block the fine nozzle.

According a first aspect of the present invention there is provided a monoazo compound of Formula (1) and salts thereof:

Formula (1) wherein: A is N, C-CI, C-CN or C-NO2; each W independently is a substituent other than carboxy, sulpho, sulphatoethylsulphonyl or vinyl sulphone; L1 is -SR3, -OR4 or -NR5R6; Z is -O-, -S- or -NR2-; R', R2, R3 and R5 are each independently H or optionally substituted alkyl; R4 is substituted alkyl; Re is a group of the formula -(C,H,,O),(C,H,,O),X, or alkyl optionally substituted by carboxy, sulpho, hydroxy(alkoxy), a group represented by T or a 5- or 6- membered heterocyclic group; or Rs and R6 together with the nitrogen to which they are attached form an optionally substituted five or six membered ring; T is an optionally substituted amino group; X is alkyl; a and b are different and from 1 to 6 p is from 1 to 4; q is from 0 to 3; j, k and m each independently is 0 to 5; and (j+k+m) is from 1 to 5; with the provisos that: (a) when j = 0 and m = 0, then at least one W is a group represented by T or is a group substituted by T; and (b) when j = 0, k = 0 and m = 1, then R5 and R6 together with the nitrogen to which they are attached do not form a morpholine ring.

Preferably A is N.

Z is preferably -NR2-, more preferably -NH-.

Preferably each W independently is halogen, preferably F or Cl; a group represented by T; hydroxy; nitro; cyano; optionally substituted alkyl, preferably optionally substituted C1.20-alkyl, more preferably optionally substituted C1-10-alkyl and especially C1-4-alkyl; optionally substituted alkoxy, preferably optionally substituted C, 20-alkoxy, more preferably optionally substituted C1.10-alkoxy and especially optionally substituted C,-alkoxy ; optionally substituted aryl, preferably optionally substituted phenyl or optionally substituted naphthyl; optionally substituted aralkyl, preferably optionally substituted C7. 12-aralkyl, more preferably phenyl-(C,-alkylene)-, especially phenylene-CH2-;-SRa ;-CORa -COORa; -SO2Ra; Or -SORa; wherein Ra is optionally substituted C,, 0-alkyl (more preferably C1.8-alkyl), optionally substituted phenyl or a group represented by T.

Preferred optional substituents carried by W and Ra include carboxy, sulpho, hydroxy, nitro, cyano, halogen and a group represented by T.

When W is a group substituted by T it is preferably of the formula -G-T or -SO2-T wherein G is an optionally substituted, optionally interrupted alkylene group G is preferably an optionally substituted, optionally interrupted alkylene group containing from 1 to 20, more preferably 1 to 10 and especially from 1 to 6 carbon atoms.

When G is an interrupted alkylene group it is preferably interrupted by one or more groups selected from -0-, -S-, -CO- -COO-, -SS- -SO,- and phenylene optionally substituted by carboxy, sulpho or hydroxy. More preferably the interrupting groups is / are -O-, -S-, -CO- or -SO2-, especially-SO2-. The interrupting group may interrupt the alkylene group at any position along the chain of carbon atoms, including a terminal position.

It is especially preferred that G carries an -SO2- group at a terminal position on the alkylene group. When G is a group of the formula -SO2(C1.10-alklene)- it is preferred that the sulphonyl group is attached to the phenyl group more preferably at a position para to the group Z An especially preferred group represented by -G-T is of the formula -SO2(C1.10-alklene)-T, more preferably-SO2(C1-6-alkylene)-T, for example -SO2C2H4-T and -SO2C3H6-T.

More preferably each W independently is optionally substituted C1-10-alkyl, optionally substituted C1-6-alkoxy, F, Cl, cyano, nitro, hydroxy, a group T , -COO(phenyl), -COO(C1-6-alkyl), -SO2-T or -SO2(C1.10-alkylene)-T.

It is especially preferred that each W independently is a group T, C16-alkyl substituted by a group T, -SO2-T or -SO2(C110-alkylene)-T.

R1 and R2 are preferably each independently H or optionally substituted C14-alkyl, more preferably H, C1-4-alkyl or C2-4-alkyl substituted by hydroxy, carboxy, sulpho or cyano. Examples include methyl, ethyl, n-propyl, iso-propyl, hydroxyethyl, cyanoethyl, sulphopropyl and carboxyethyl. It is especially preferred that R1 and R2 are H.

R4 is preferably substituted C1-10-alkyl, more preferably substituted C1-6-alkyl and especially substituted C1-4-alkyl. The substituents are preferably selected from hydroxy, more preferably alkoxy (preferably C1 6-alkoxy), hydroxy(C1-6-alkoxy), carboxy, sulpho, a group represented by T or a 5- or 6- membered heterocyclic ring.

When any of R3, R5 or R6 is alkyl it is preferably C1-10-alkyl, more preferably C1-6-alkyl and especially C1-4-alkyl.

Preferred substituents on R6 are selected from carboxy, sulpho, hydroxy(C1-6-alkoxy)-, a group represented by T and a 5- or 6- membered heterocyclic ring.

Preferred substituents on R3 and R5 are the preferred substitutents on R6, C1-6-alkoxy or -OH, more preferably the preferred substituents on R6 or C1-6-alkoxy.

When a substituent on any of R3, R4, R5 or R6 is a 5- or 6- membered heterocyclic ring, it preferably comprises carbon atoms and one or two atoms selected from 0, N and S, more preferably one 0 or S atom and four or five carbon atoms. Preferred rings are furanyl, tetrahydrofuranyl, pyranyl, dihydropyranyl, tetrahydropyranyl or thienyl each of which is optionally substituted. Especially preferred rings are furanyl and tetrahydrofuranyl, more especially tetrahydrofuranyl rings each of which is optionally substituted by -COOH.

When any of R3, R4, R5 or R6 is alkyl substituted by hydroxy(C1-6-alkoxy) it is preferably of the formula -(C2-6alkylene)O(C2-6-alkylene)OH, for example -C2H4OC2H4OH and -C3H6OC2H4OH.

An especially preferred substituted alkyl group which may be represented by any of R3, R4, R5 and Re is of the formula (CdH2d)-T where d is 1 to 6, more preferably 2 to 6 and T is as hereinbefore defined.

Preferably X is C14-alkyl, more preferably methyl.

Preferably a and b are each independently 2 to 6, more preferably 2 or 3.

Preferably p is 1 or 2. Preferably q is 0.

When R6 is a group of the formula -(CaH2aO)p(CbH2bO)qX it is preferably -(C2-6-alkylene)O(C2-6-alkylene)OC1-4-alkyl, for example -C2H4OC2H4OCH3, -C2H4OC3H6OCH3, -CH2CH(CH3)CH2OC2H4OCH3 and C3HeOC2H4OC2H5.

When R5 and R6 together with the nitrogen to which they are attached form an optionally substituted 5 or 6 membered ring it is preferably optionally substituted morpholine, or more preferably optionally substituted piperazine. Preferred optional substituents are selected from hydroxy, carboxy, sulpho, C1-6-alkoxy, C1-6-alkyl and C14-alkyl substituted by hydroxy, carboxy, sulpho or a group represented by T. More preferably the substituents are selected from C1-6-alkyl or a group of the formula -C, 6-alkylene-T. When R5 and R6 together with the nitrogen to which they are attached form a substituted piperazine ring it is preferably substituted on a nitrogen atom.

Preferred groups represented by T independently have a pka of from 12 to 4, more preferably of from 10 to 6.

Preferably T is a group of the formula -NR7R8 wherein R7 and RB are each independently H, optionally substituted alkyl, a group of the formula -COB wherein B is H, optionally substituted alkyl or optionally substituted aryl; or R7 and R8 together with the nitrogen to which they are attached form an optionally substituted morpholine or piperazine ring.

When R7, R8 or B is optionally substituted alkyl it is preferably optionally substituted C1-6-alkyl, more preferably optionally substituted C14-alkyl. Preferred substituents are selected from carboxy, sulpho, hydroxy, amino and C1-4-alkoxy.

When B is optionally substituted aryl it is preferably optionally substituted phenyl, more preferably phenyl optionally substituted by carboxy, sulpho, C1-4-alkyl, C1-4-alkoxy, C1-4-hydroxyalkyl, halo, amino or hydroxy.

Preferred groups of the formula -COB include -CO(C1-4-alkyl), -COphenyl, -COCH3, -COCH2CH3 and -COCH2CH2CH3.

When R7 and R8 together with the nitrogen to which they are attached form a substituted morpholine or piperazine ring it is preferably substituted by a group of the formula -M-NR9R10 where M is alkylene and R9 and R10 each independently is H, C1-6-alkyl or C,-alkyl substituted by hydroxy, carboxy, sulpho, amino or C,-alkoxy.

M is preferably C1-6-alkylene, more preferably C24-alkylene and especially -(CH2)9-, where g is from 2 to 6.

Preferred groups represented by T include -NH2; -NH(C1-6-alkyl), for example ethylamino; -N(C1-6-alkyl)2, for example di-ethylamino; -NHCO(C1-4-alkyl), for example -NHCOCH3 and -NHCOCH2CH3; -NH(C1-6-hydroxyalkyl), for example -NH(C2H4OH); -N(C1-6-hydroxyalkyl)2, for example -N(C2H4OH)2; morpholino; piperazinyl; and substituted piperazinyl groups of the Formula (2):

Formula (2) wherein M, R9 and R10 are as hereinbefore defined.

Preferred groups of the Formula (2) include:

7Th 7Th - N N--(C,,-alkylene)NH, -N N-(C,,-alkylene)NH(C,,-alkyl) \/and \ J It is especially preferred that L1 is a group of the formula -NR5R6, more preferably -NHR6 or piperazinyl optionally substituted by C1-6-alkyl or a group of the formula -(C14-alkylene)-T, wherein T, R5 and R6 are as hereinbefore defined. when L1 is a group of the formula -NHR6, R6 is preferably C1-6-alkyl optionally substituted by furanyl, tetrahydrofuranyl or a group T as hereinbefore defined; more preferably R6 is of the formula -(CdH2d)-T wherein d is 1 to 6.

Examples of -NHR6 include:

In a first preferred embodiment k = 0; m = 0; and j = 1 or 2 (more preferably 1).

In a second preferred embodiment k = 0; j = 0; and m = 1 or 2 (more preferably 1).

In a third preferred embodiment j = 0; m = 1 or 2; k = 1 or 2; (m + k) = 2 or 3 (preferably 2); and each W independently is: optionally substituted C1-20-alkyl, optionally substituted C1-20-alkoxy, a group T, halogen, hydroxy, cyano, nitro, -COO(C1.20-alkyl), -COO(phenyl) -G-T or -SO2-T; wherein T and G are as hereinbefore defined.

In a fourth preferred embodiment m = 0; j = 1 or 2; k = 1 or 2; (j + k) = 2 or 3 (preferably 2); and each W independently is as defined in the third preferred embodiment.

In a fifth preferred embodiment j = 0; m = 0; k = 1 or 2 (more preferably 1); and each W independently is as defined in the third preferred embodiment, with the proviso that at least one W1 is a group T or is a group substituted by T.

In a sixth preferred embodiment j = 1 or 2; m = 1 or 2; and (m + j) = 2 or 3 (preferably 2).

In view of the forgoing preferences a preferred monoazo compound according to the first aspect of the present invention is a compound of the Formula (3) and salts thereof:

Formula (3) wherein: Z1 is -O-, -S- or -NR11-; R11 is H or C1-4-alkyl optionally substituted by hydroxy, carboxy, sulpho or cyano; L2 is -SR12, -OR13 or -NR14R15; R13 is C,., 0-alkyl substituted by hydroxy, carboxy, sulpho, furanyl, tetrahydrofuranyl, C1-6-alkoxy, or by a group represented by T1; R15 is -(C2-6-alkylene)O(C2-6-alkylene)OX1 or C1-10-alkyl optionally substituted by carboxy, sulpho, furanyl, tetrahydrofuranyl, C1-6-alkoxy or by a group represented by T'; R12 and R14 each independently is H, or a group as defined for R'3; or R'4 and R15 together with the nitrogen to which they are attached form a piperazine ring optionally substituted by C, 6-alkyl or C14-alkyl substituted by T'; each W1 independently is Cl, nitro, cyano, C1-10-alkyl, or C,, 0-alkyl substituted by hydroxy, carboxy, sulpho, or C1-6-alkoxy; each Y is T1, C1-6-alkyl substituted by T1, -SO2-T1 or -SO2(C1-10-alkylene)-T1; xl is H or C1-4-alkyl; T1 is -NR9R10 or a group of the Formula (2); f, g, t and d are each independently 0 to 2; (f+g+t+d) = 1 to 5; R9, R10 and the group of the Formula (2) are as hereinbefore defined; with the proviso that when f = 0 and g = 0, that d = 1 or 2.

X1 is prefeably C1-4-alkyl, more preferably methyl.

R13is preferably C,. 6-alkyl substituted by carboxy, sulpho, tetrahydrofuranyl or by a group represented by T1.

R12 and R14 are preferably each independently H or C1-6-alkyl optionally substituted by carboxy, sulpho, tetrahydrofuranyl or by a group represented by T1.

W1 is preferably C1-6-alkyl.

Preferably Z1 is -NR11-, L2 is -NR14R15 and RIA and R'5 are as herein before defined.

Especially preferred compounds of the Formula (3) are those wherein Z1 is -NR11- L2 is -NHR15 or a piperazine ring optionally substituted by C1-6-alkyl or C1-6-alkyl substituted by T1, wherein R11, R15 and T1 are as hereinbefore defined. More especially L2 is -NHR1.

Preferably f, g, d and t each independently is 0 or 1.

When (f + g) is 1 or more, d is preferably 0. More preferably, when (f + g) is 1 or more and d = 0, then W1 is C1-6-alkyl.

When f and g are both 0, preferably d = 1 and t = 0.

The compounds of Formula (1) may be in the free acid or salt form. Preferred salts are water-soluble, for example alkali metal salts, especially lithium, sodium and potassium salts, ammonium and substituted ammonium salts. Especially preferred salts are salts with sodium, ammonia and volatile amines. The dyes may be converted into a salt using known techniques. For example, an alkali metal salt of a dye may be converted into a salt with ammonia or an amine by dissolving an alkali metal salt of the dye in water, acidifying with a mineral acid and adjusting the pH of the solution to pH 9 to 9.5 with ammonia or the amine and removing the alkali metal cations by dialysis.

The dyes of Formula (1) may be prepared using conventional techniques for the preparation of azo dyes. For example a suitable method comprises condensing a compound of the Formula (4) with a compound of the Formula L'H:

Formula (4) wherein: R1, Z, A, L', W, j, k and m are as hereinbefore defined.

The condensation is preferably performed in a liquid medium, more preferably an aqueous medium and especially water. Temperatures of 15"C to 1000C are preferred, more preferably from 60 to 900C. Preferably a reaction time of 1 to 48, more preferably 3 to 24 hours is used.

The condensation is preferably performed in the presence of a base. The base may be any inorganic base for example, ammonia, an alkali metal or alkali earth metal hydroxide, carbonate or bicarbonate, or an organic base. Preferred organic bases are tertiary amines for example, N-alkylated heterocycles, for example N-(C,-alkyl) morpholine, N-(C1 -alkyl) piperidine, N, N'-di (C1 -alkyl) piperazine ; tri (C14-alkyl) amines, for example triethylamine, and optionally substituted pyridines, especially pyridine.

The amount of base used may be varied between wide limits but it is preferred to use less than 40, more preferably less than 10 and especially from 3 to 5 moles for each mole of the compound of Formula (4).

After the condensation the product may be isolated by precipitating the product as a salt from the reaction mixture for example by the addition of a suitable alkali metal salt, especially sodium chloride. Altematively, the product may be isolated in its free acid form by acidifying the reaction mixture, preferably using a mineral acid, especially hydrochloric acid. Where the product precipitates as a solid it may be separated from the mixture by filtration.

If desired unwanted anions may be removed from the product of the above process by dialysis, osmosis, ultrafiltration or a combination thereof.

The product of the above process may be converted, if desired, to the NH4+, quaternary ammonium or organic amine salt by the addition of ammonia, ammonium hydroxide, primary, secondary, tertiary or quatemary amine. When the base used in the condensation process is an organic amine an excess may be used so that the compound of Formula (1) is formed as the organic amine salt.

The compound of the Formula (4) may be prepared using conventional techniques, for example by: (1) diazotising 2-naphthylamine-1-sulphonic acid to give the corresponding diazonium salt; (2) coupling the diazonium salt from stage (1) with 1-acetamido-8-naphthol-3,6-disulphonic acid at a pH > 7, preferably at a pH of from 8 to 9; (3) alkaline hydrolysis of the product of stage (2) to remove the acetyl group;.

(4) condensing the product from stage (1) with a compound of the formula:

wherein A is as hereinbefore defined; and (5) condensing the product from stage (4) with approximately 1 molar equivalent of the compound of the formula:

wherein Z, j, k and m are as hereinbefore defined.

The diazotisation in stage (1) is preferably performed in an aqueous medium at a pH below 7 in the presence of a suitable diazotisation agent. Dilute mineral acid, e.g. HCI or H2SO4, is preferably used to achieve the desired acidic conditions. Conveniently the diazotisation agent is formed in-situ, for example by dissolving an alkali metal nitrite, preferably sodium nitrite, in a molar excess of mineral acid, preferably HCI. Normally at least one mole of diazotisation agent per mole of 2-naphthylamine-1-sulphonic acid, preferably from 1 to 1.25 moles will be used in the diazotisation.

The temperature of the diazotisation is not critical and may conveniently be carried out at from 5cm to 20"C, preferably from 0 to 10 C and especially from 0 to 5"C.

The hydrolysis in stage (3) is preferably performed at a pH in the range 9 to 14.

The temperature during hydrolysis is preferably from 40 to 90"C.

The compounds of the Formula (1) may exist in tautomeric forms other than those shown in this specification. These tautomers are included within the scope of the present claims.

According to a second aspect of the present invention there is provided an ink comprising: (a) from 0.01 to 30 parts in total of one or more compounds of the Formula (1) and salts thereof as hereinbefore defined in the first aspect of the invention; and (b) from 70 to 99.99 parts of a medium comprising (i), (ii) or (iii): (i) a mixture of water and an organic solvent; (ii) an organic solvent free from water; or (iii) a low melting point solid; wherein all parts are by weight and the number of parts of (a)+(b)=100.

The number of parts of component (a) is preferably from 0.1 to 20, more preferably from 0.5 to 15, and especially from 1 to 5 parts. The number of parts of component (b) is preferably from 99.9 to 80, more preferably from 99.5 to 85, especially from 99 to 95 parts.

Component (a) of the ink may contain a single compound, or two or more compounds according to the first aspect of the invention. Preferably the compound(s) in component (a) of the ink is of the Formula (3) as hereinbefore defined in relation to the first aspect of the present invention.

When the medium is a mixture of water and an organic solvent or an organic solvent free from water, preferably component (a) is completely dissolved in component (b). Preferably component (a) has a solubility in component (b) at 20"C of at least 10%.

This allows the preparation of concentrates which may be used to prepare more dilute inks and reduces the chance of the dye precipitating if evaporation of the liquid medium occurs during storage.

When the medium comprises a mixture of water and an organic solvent, the weight ratio of water to organic solvent is preferably from 99:1 to 1:99, more preferably from 99:1 to 50:50 and especially from 95:5 to 80:20.

It is preferred that the organic solvent present in the mixture of water and organic solvent is a water-miscible organic solvent or a mixture of such solvents. Preferred water-miscible organic solvents include C14-alkanols, preferably methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, n-pentanol, cyclopentanol and cyclohexanol; linear amides, preferably dimethylfomtamide or dimethylacetamide; ketones and ketone-alcohols, preferably acetone, methyl ether ketone, cyclohexanone and diacetone alcohol; water-miscible ethers, preferably tetrahydrofuran and dioxane; diols, preferably diols having from 2 to 12 carbon atoms, for example pentane-1 ,5-diol, ethylene glycol, propylene glycol, butylene glycol, pentylene glycol, hexylene glycol and thiodiglycol and oligo- and poly-alkyleneglycols, preferably diethylene glycol, triethylene glycol, polyethylene glycol and polypropylene glycol; triols, preferably glycerol and 1 2,6-hexanetriol; mono-C, -alkyl ethers of diols, preferably mono-C,,-alkyl ethers of diols having 2 to 12 carbon atoms, especially 2-methoxyethanol, 2-(2-methoxyethoxy)ethanol, 2-(2-ethoxyethoxy)-ethanol, 2-[2-(2-methoxyethoxy)ethoxyiethanol, 2-[2-(2-ethoxyethoxy)-ethoxyl-ethanol and ethyleneglycol monoallylether; cyclic amides, preferably 2-pyrrolidone, N-methyl-2-pyrrolidone, Nethyl-2-pyrrolidone, caprolactam and 1, 3-dimethylimidazolidone; cyclic esters, preferably caprolactone; sulphoxides, preferably dimethyl sulphoxide and sulpholane. Preferably the liquid medium comprises water and 2 or more, especially from 2 to 8, water-soluble organic solvents.

Especially preferred water-soluble organic solvents are cyclic am ides, especially 2-pyrrolidone, N-methyl-pyrrolidone and N-ethyl-pyrrolidone; diols, especially 1, 5-pentane diol, ethyleneglycol, thiodiglycol, diethyleneglycol and triethyleneglycol; and mono- 4-alkyl and C, 4-alkyl ethers of diols, more preferably mono- 4-alkyl ethers of diols having 2 to 12 carbon atoms, especially 2-methoxy-2-ethoxy-2-ethoxyethanol.

A preferred medium comprises: (a) from 75 to 95 parts water; and (b) from 25 to 5 parts in total of one or more solvents selected from diethylene glycol, 2-pyrrolidone, thiodiglycol, N-methylpyrrolidone, cyclohexanol, caprolactone, caprolactam and pentane-1,5-diol; wherein the parts are by weight and the sum of the parts (a) and (b) = 100.

Examples of further suitable ink media comprising a mixture of water and one or more organic solvents are described in US 4,963,189, US 4,703,113, US 4,626,284 and EP 4,251 ,50A.

When the liquid medium comprises an organic solvent free from water, (i.e. less than 1% water by weight) the solvent preferably has a boiling point of from 30 to 2000C, more preferably of from 40 to 1500C, especially from 50 to 125"C. The organic solvent may be water-immiscible, water-miscible or a mixture of such solvents. Preferred water-miscible organic solvents are any of the hereinbefore described water-miscible organic solvents and mixtures thereof. Preferred water-immiscible solvents include, for example, aliphatic hydrocarbons; esters, preferably ethyl acetate; chlorinated hydrocarbons, preferably CH2Cl2; and ethers, preferably diethyl ether; and mixtures thereof.

When the liquid medium comprises a water-immiscible organic solvent, preferably a polar solvent is included because this enhances solubility of the dye in the liquid medium. Examples of polar solvents include C"-alcohols. In view of the foregoing preferences it is especially preferred that where the liquid medium is an organic solvent free from water it comprises a ketone (especially methyl ethyl ketone) For an alcohol (especially a C1-4-alkanol, more especially ethanol or propanol).

The organic solvent free from water may be a single organic solvent or a mixture of two or more organic solvents. It is preferred that when the medium is an organic solvent free from water it is a mixture of 2 to 5 different organic solvents. This allows a medium to be selected which gives good control over the drying characteristics and storage stability of the ink.

Ink media comprising an organic solvent free from water are particularly useful where fast drying times are required and particularly when printing onto hydrophobic and non-absorbent substrates, for example plastics, metal and glass.

Preferred low melting solid media have a melting point in the range from 60"C to 125 C. Suitable low melting point solids include long chain fatty acids or alcohols, preferably those with C14 chains, and sulphonamides. The compound of Formula (1) may be dissolved in the low melting point solid or may be finely dispersed in it.

The compounds according to the first aspect of the present invention exhibit a high solubility in aqueous media, accordingly it is preferred that the liquid medium is a mixture of water and one or more water miscible organic solvent(s).

The ink may also contain additional components conventionally used in ink jet printing inks, for example viscosity and surface tension modifiers, corrosion inhibitors, biocides, kogation reducing additives and surfactants which may be ionic or non-ionic.

The presence of impurities in an ink jet printing ink can result in the formation of precipitates in the ink. This is undesirable because the precipitates can block the narrow ink jet nozzle in the printer. Therefore, the compound( 201 Glossy Paper, Canon HG 101 High Gloss Film (all available from Canon Inc.), Wiggins Conqueror paper (available from Wiggins Teape Ltd), Xerox Acid Paper and Xerox Alkaline paper, Xerox Acid Paper (available from Xerox).

A fourth aspect of the present invention provides a paper, an overhead projector slide or a textile material printed with an ink according to the second aspect of the present invention, or by means of the process according to the third aspect of the present invention.

When the substrate is a textile material the ink according to the invention is preferably applied thereto by: i) applying the ink to the textile material using an ink jet printer; and ii) heating the printed textile material at a temperature of from 50"C to 2500C Preferred textile materials are natural, synthetic and semi-synthetic materials.

Examples of preferred natural textile materials include wool, silk, hair and cellulosic materials, particularly cotton, jute, hemp, flax and linen. Examples of preferred synthetic and semi-synthetic materials include polyamides, polyesters, polyacrylonitriles and polyurethanes.

Preferably the textile material has been treated with an aqueous pre-treatment composition comprising a thickening agent and optionally a water-soluble base and a hydrotropic agent and dried prior to step i) above.

The pre-treatment composition preferably comprises a solution of the base and the hydrotropic agent in water containing the thickening agent. Particularly preferred pre-treatment compositions are described more fully in European Patent Application No.534660A1.

According to a fifth aspect of the present invention there is provided an ink jet printer cartridge containing an ink, characterised in that the ink contains a compound according to the first aspect of the present invention.

Preferably the ink contained in the ink jet printer cartridge is an ink according to the second aspect of the present invention.

The invention is further illustrated by the following Examples in which all parts and percentages are by weight unless otherwise stated.

Example 1 Dye (i)

Dye (1) was prepared using stage (i) to (iv) described below: Stage (i) 2-Naphthylamine-1-sulphonic acid (0.304M, 67.849 at 100% was added to water (500ml) and cooled to 0-5"C. Concentrated HCI (150ml) was then added followed by 2N NaNO2 (150ml). The solution was stirred for 1 hour at 0-5"C and excess NaNO2 was destroyed by addition of sulphamic acid.

To the above solution was added 1-acetamido-8-naphthol-3,6-disulphonic acid (0.304M, 109.83g at 100%) in water (500ml). The pH was then raised to 7.0 by addition of a concentrated solution of NaOH and the solution was stirred for 3 hours at 0-5"C. The solution was then adjusted to 1. 5M NaOH by addition of NaOH pellets and was heated to 850C for 6 hours.

The pH was then reduced to 7.0 by addition of concentrated HCI and the solution was salted to 20% with NaCI. The resulting precipitate was filtered off, washed and dried.

Strength estimated at 71.6%.

Stage (ii) The product of stage (i) above (86.5g, 0.1 mole at 71.6% strength) was dissolved in water (800ml). Cyanuric chloride (19.369, 0.105 mole) was dissolved in acetone (200ml) and added to icelwater (3009). To this was added the solution of the product of stage (i) allowing the pH to fall. The resulting solution was stirred for 2 hours at 0-5"C.

The pH was then raised to 7.0 by addition 2N NaOH solution and the solution was allowed to self-warm to room temperature.

Staae (iii) 4-amino-3-carboxybenzenesulphonic acid (0.11 mole, 23.879) was added to the solution from stage (ii) whilst maintaining the pH maintained at 7 by addition of 2N NaOH.

The solution was stirred at room temp and pH 7 for 6 hours and then salted to 20% with NaCI. The resulting precipitate was filtered off washed and dried.

Stage (iv) The product of stage (iii) was dissolved in water (11). To this solution was added N,N-dimethylethylenediamine (0.11 mole 9.68g). The solution was heated to 80"C for 3 hours at pH 10.0 maintaining the pH by the addition of 2N NaOH. After cooling the solution to room temperature, the pH was adjusted to 7 by the addition of concentrated HCI and salted to 20% with NaCI.

The resulting precipitate was isolated by filtration, dialysed and converted to the ammonium salt by ion exchange solution to give the title product.

Ink Ink (1) was prepared by dissolving 2 parts of Dye (1) in 98 parts of a mixture comprising 90 parts water and 10 parts 2-pyrrolidone. The pH of the ink was 8.5.

Ink Jet Printing Ink 1 was applied to plain paper using a Hewlett Packard HP 660C ink jet printer, giving prints which were bright magenta in shade.

The optical density of the resulting prints was 1.07, as measured using an X-Rite densitometer.

The prints exhibited an excellent light fastness. After 50 hours exposure in an Atlas Weatherometer the optical density of the prints had only reduced by 33.8%.

Examples 2 to 21 Dyes, which in the free acid form are of the Formula:

were prepared by condensing the product of stage (ii) in Example 1 with an approximately equimolar quantity of the compound L1H shown in Table 1. The resulting product was then condensed with an approximately equimolar quantity of the compound L2H shown in Table 1 using analogous conditions to those in Example 1.

Each dye was purified by dialysis and then converted into the ammonium salt using the methods described in Example 1.

Each dye, in the form of its ammonium salt, was formulated into an ink comprising 2 parts of the relevant dye dissolved in 98 parts of a mixture comprising 10 parts 2-pyrrolidone and 90 parts water. Each ink was ink jet printed onto plain paper and the light fastness and optical density of the resulting prints was measured as in Example 1.

Thus in Column 5 headed "Light-Fastness" , the figure refers to the % reduction in optical density after exposure for 50 hours in the Atlas Weatherometer.

TABLE 1

Example L'H L2H Optical Light ~ Density Fastness 2 NH, /7 1.0 48.8 6 COOH H,NCZH,N NH SO,H 23.9 3 rY 7 I.o 6 COOH HN O SO,H 4 Hz 7 107 31 05 ooH HN NH SO,H 5 Hz NH2CH2CH,N(CH3)2 12 35 i 6 H2N COOH HN NCH2CH2NH2 1.1 38 H2N cOOH HN NCH,CYNH, 7 H,NCOOH H,NCH,CH,N NCH,CH,NH, s COOH 7 1.06 77 H,NCH,CH,N\ NCH,CH,NH, 9 COOH /-7 1.08 49 - HN NcH2cH2NH2 H2N\/ 'U COOH 10/=\ NH2CH2CH2N(CH3)2 1.208 51 H,N 1 1 H2N < COOH O NCH2CH2CH2NH2 1. 12 36 TABLE 1 (continued)

Example L'H L2H Optical Light Density Fastness 12 HO3S HN O 1.2 25.44 H2NM 'U 13 NH2 H2NC2H4N(CH3)2 1.2 33 SO3H CH3 14 NH2 7Th 1.25 15 (rso3H H, NCHsCH2CH2NuNCH2CH2CH2NH2 15 H3C COOH NH2CH2CH2OCH2CH2OH 1. 16 17 H 2N 16 H2N&num;$/ OOH NH2ccH2N(cH 1.12 2 1. 12 30 OH 17 N F\ 1.12 51 17 HN NH2CH2CH2NwO 1. 12 510 'U H3C COOH TABLE 1 (continued)

Example L1H L2H Optical Light Density Fastness 18 - /m 1.16 48 H2N / NH2cH2cHN'UNH H3c cooH 19 - 'em 1.18 33 HN NH2cH2cHN 0 'U HaC COOH 20 HNS0NHCHCHCH 7Th 7Th 1.29 31 co o, o, 21 - 7Th NH2CH2CH2OCH2CH2OH 1.09 31 I The compound of the Formula L'H in examples 20 and 21 was prepared as follows: N-Acetylsulfanilyl chloride (116.5g, 0.5 mole) was stirred in water (300ml) . To this was added 4-(3-Aminopropyl)morpholine (108.15g, 0.75 mole) dropwise over approx. 30 minutes. The reaction mixture was then stirred for 12 hours at room temperature.

Concentrated HCI (100ml) was then added and the solution heated to 70"C for 5 hours.

The pH was then raised to 7 by the addition of concentrated NaOH and the solution salted to 20% with NaCI. The resulting precipitate was filtered off, washed and dried to leave the product of the formula:

Example 22 The inks described in Tables 2 and 3 may be prepared wherein the Dye described in the first column is the Dye made in the above example of the same number. Numbers quoted in the second column onwards refer to the number of parts of the relevant ingredient and all parts are by weight. The inks may be applied to paper by thermal or piezo ink jet printing.

The following abbreviations are used in Table 2 and 3: PG = propylene glycol DEG = diethylene glycol NMP = N-methyl pyrrolidone DMK = dimethylketone IPA = isopropanol MEOH = methanol 2P = 2-pyrrolidone MIBK = methylisobutyl ketone P12 = propane-1,2-diol BDL = butane-2,3-diol CET= cetyl ammonium bromide PHO = Na2HPO4 and TBT = tertiary butanol TDG = thiodiglycol TABLE 2

Dye Dye Water PG EG NMP DMK NaOH Na IPA MEOH 2P MIBK Content Stearate 1 2.0 80 5 6 4 5 2 3.0 90 5 4.8 0.2 3 10.0 85 3 3 3 5 1 5 2.1 91 8 1 3 3.1 86 5 0.2 4 4.8 5 1.1 81 9 0.5 0.5 9 6 2.5 60 4 15 3 3 6 5 4 6 5 65 20 5 10 7 2.4 75 5 4 5 6 5 8 4.1 80 3 4.7 2 10 0.3 8 3.2 65 5 4 6 5 4 6 5 9 5.1 96 4 01 10.8 90 5 5 11 10.0 80 2 6 2 5 1 4 12 1.8 80 5 15 13 2.6 84 11 5 14 3.3 80 2 10 2 6 15 12.0 90 6.7 0.3 3 16 5.4 69 2 20 2 1 3 3 17 6.0 91 4 5 TABLE 3

Dye Dye Water PG EG NMP CET TBT TDG BDL PHO 2P PI2 Content 18 3.0 80 15 0.2 4.8 2 9.0 90 5 4.65 1.2 3.8 2 1.5 85 5 5 0.15 0.2 11 2.5 90 6 3.88 0.12 19 3.1 82 4 8 0.3 5.7 20 0.9 85 9.8 5 0.2 1 8.0 90 5 4.7 0.3 2 4.0 70 10 4 1 4 11 21 2.2 75 4 10 3 2 6 1 10.0 91 6 3 2 9.0 76 9 7 3.0 0.95 4.05 1 5.0 78 5 11 6 14 5.4 86 7 4.6 7 5 2.1 70 5 5 5 0.1 0.2 5 0.1 5 8 2.0 90 10 9 2 88 10 2 12 5 78 5 12 5 11 8 70 2 8 15 5 10 10 80 8 12 13 10 80 10

Claims (16)

1. CLAIMS 1. A monoazo compound of Formula (1) and salts thereof:

   Formula (1) wherein: A is N, C-CI, C-CN or C-NO2; each W independently is a substituent other than carboxy, sulpho, suiphatoethylsulphonyl or vinyl sulphone; L1 is -SR3, -OR4 or -NR5R6; Z is-O-, -S- or -NR2-; Rt, R2, R3 and R5 are each independently H or optionally substituted alkyl; R4 is substituted alkyl; R6 is a group of the formula -(CaH2aO)p(CbH2bO)qX, or alkyl optionally substituted by carboxy, sulpho, hydroxy(alkoxy), a group represented by T or a 5- or 6- membered heterocyclic group; or R5 and R6 together with the nitrogen to which they are attached form an optionally substituted five or six membered ring; T is an optionally substituted amino group; X is alkyl; a and b are different and from 1 to 6; p is from 1 to 4; q is fromOto 3; j, k and m each independently is 0 to 5; and (j+k+m) is from 1 to 5; with the provisos that: (a) when j = 0 and m = 0, then at least one W is a group represented by T or is a group substituted by T; and (b) when j = 0, k = 0 and m = 1, then R5 and R6 together with the nitrogen to which they are attached do not form a morpholine ring.
2. 2. A compound according to claim 1 wherein: each W independently is halogen, a group represented by T, hydroxy, nitro, cyano, optionally substituted alkyl, optionally substituted alkoxy, optionally substituted aryl, optionally substituted aralkyl, -SRa, -CORa, -COORa, -SO2Ra or -SORa; is is optionally substituted C, 10-alkyl, optionally substituted phenyl or a group represented by T ; and T is as defined in claim 1.
3. 3. A compound according to either claim 1 or claim 2 wherein: each W independently is optionally substituted C,, 0-alkyl, optionally substituted C1-6-alkoxy, F, Cl, cyano, nitro, hydroxy, a group T , -COO(phenyl), -COO(C1.6-alkyl), -SO2-T or -SO2(C1-10-alkylene)-T; and T is as defined in claim 1.
4. 4. A compound according to any one of the preceding claims wherein each T independently has a pKa of from 12 to 4.
5. 5. A compound according to any of the preceding claims wherein: T is a group of the formula -NR7R8; R7 and R8 are each independently H, optionally substituted alkyl, a group of the formula -COB; or R7 and R8 together with the nitrogen to which they are attached form an optionally substituted morpholine or piperazine ring; and B is H, optionally substituted alkyl or optionally substituted aryl.
6. 6. A compound according to any one of the preceding claims wherein A is N.
7. 7. A compound according to any one of the preceding claims wherein: L1 is a group of the formula -NR5R6; and R5 and Re are as defined in claim 1.
8. 8. A compound according to claim 1 wherein the monoazo compound of the Formula (1) is of the Formula (3) and salts thereof:

   Formula (3) wherein: Z1 is -O-, -S- or -NR11-; R11 is H or C1-4-alkyl optionally substituted by hydroxy, carboxy, sulpho or cyano; L2 is -SR12, -OR13 or -NR14R15; R13 is C1.10-alkyl substituted by hydroxy, carboxy, sulpho, furanyl, tetrahydrofuranyl, C1-6-alkoxy, or by a group represented by T1; R15 is -(C2-6-alkylene)O(C2-6-alkylene)OX1 or C1-10-alkyl optionally substituted by carboxy, sulpho, furanyl, tetrahydrofuranyl, C1-6-alkoxy or by a group represented by T'; R12 and R'4 each independently is H, or a group as defined for R'3; or R'4 and R15 together with the nitrogen to which they are attached form a piperazine ring optionally substituted by C1-6-alkyl or C1-6-alkyl substituted by T1; each WI independently is Cl, nitro, cyano, C1-10-alkyl, or C1-10-alkyl substituted by hydroxy, carboxy, sulpho, or C1-6-alkoxy; each Y is T', C1-6-alkyl substituted by T1 , -SO2-T1 or -SO2(C1-10-alkylene)-T1; X1 is H or C1-4-alkyl; T1 is -NR9R10 or a group of the Formula (2):

   Formula (2) M is alkylene; R9 and R10 each independently is H, C1-6-alkyl or C1-6-alkyl substituted by hydroxy, carboxy, sulpho, amino or C1-4-alkoxy; f, g, t and d are each independently 0 to 2; (f+g+t+d) = 1 to 5; with the proviso that when f = 0 and g = 0, that d = 1 or 2.
9. 9. A compound according to claim 8 wherein: Z1 is -NR'1-; L2 is -NHR15 or a piperazine ring optionally substituted by C1-6-alkyl or C1-6-alkyl substituted by T1; and R", R15 and T1 are as defined in claim 8.
10. 10. An ink comprising: (a) from 0.01 to 30 parts in total of one or more compounds according to any one of claims 1 to 9; and (b) from 70 to 99.99 parts of a medium comprising (i), (ii) or (iii): (i) a mixture of water and an organic solvent; (ii) an organic solvent free from water; or (iii) a low melting point solid; wherein all parts are by weight and the number of parts of (a)+(b)=100.
11. 11. An ink according to claim 10 wherein the compound(s) in component (a) of the ink is of the Formula (3) as defined in claim 8.
12. 12. A process for printing an image on a substrate comprising applying thereto an ink containing a compound according to any one of claims 1 to 9 by means of an ink jet printer.
13. 13. A paper, an overhead projector slide or a textile material printed with an ink according to either claim 10 or claim 11, or by means of the process according to claim 12.
14. 14. An ink jet printer cartridge containing an ink, characterised in that the ink contains a compound according to any one of claims 1 to 9.
15. 15. A dye substantially as hereinbefore described with reference to any one of the Examples.
16. 16. An ink substantially as hereinbefore described with reference to any one of the Examples.