GB2332208A - 4-(2-amino-3,6-disulpho-8-hydroxynaphth-1-ylazo)anilino- pyrimidine or 1,3,5-triazine dyes & their use in ink jet printing inks - Google Patents

Abstract

Compounds of Formula (6): wherein: L<SP>3</SP> is L<SP>1</SP> or a labile atom or group; L<SP>4</SP> is L<SP>2</SP> or a labile atom or group; A is N, C-CI, C-CN or C-NO 2 ; R<SP>1</SP> is H or optionally substituted alkyl; G is sulpho, carboxy, optionally substituted alkyl, optionally substituted alkoxy, -CF 3 or -PO 3 H 2 ; L<SP>1</SP> and L<SP>2</SP> are each independently -SR<SP>2</SP>, -OR<SP>3</SP> or -NR<SP>4</SP>R<SP>5</SP>; R<SP>2</SP>, R<SP>3</SP>, R<SP>4</SP> and R<SP>5</SP> are each independently H, optionally substituted alkyl or aryl optionally substituted by a group other than vinyl sulphone, sulphatoethylsulphonyl or phosphonooxyethylsulphonyl; or R<SP>4</SP> and R<SP>5</SP> together with the nitrogen to which they are attached form an optionally substituted five or six membered ring; provided that at least one of L<SP>3</SP> and L<SP>4</SP> contain one or more substituents selected from carboxy, sulpho and -PO 3 H 2 , may be formulated as an ink and used in an ink jet printer cartridge for use in printing. (57) continued overleaf (57) cont Dyes of formula (6) wherein L<SP>3</SP> is L<SP>1</SP> only and L<SP>4</SP> is L<SP>2</SP> only, but wherein the proviso for L<SP>3</SP> and L<SP>4</SP> still applies, are claimed as novel compounds. An ink preferably comprises: (a) from 0.01 to 30 parts of a compound of the Formula (6); and (b) from 70 to 99.99 parts of a medium comprising a mixture of water and an organic solvent, an organic solvent free from water, or a low melting point solid; wherein all parts are by weight and the number of parts of (a)+(b)=100:

Description

1 1 COMPOUNDS AND COMPOSITION 2332208 This invention relates to dyes, to

inks and to their use in ink jet printing ("UP"). UP 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 UP. 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 to the present invention there is provided a mono-azo compound of Formula (1) and salts thereof:

G R H03S NH2 1 A N-6--N N 4P N W--( OH H03s Formula (1) wherein: A R' G L' and L 2 R 2, R 3 R and R' L' L 2 is N, C-C], C-CN or C-N02; is H or optionally substituted alky]; is sulpho, carboxy, optionally substituted alkyl, optionally substituted alkoxy, -CF3 or -P03H2; are each independently -SR 2, -OR 3 or -NR 4 W; are each independently H, optionally substituted alkyl or aryl optionally substituted by a group other than vinyl sulphone, sulphatoethyisulphonyl or phosphonooxyethyisulphonyl; or R and R' together with the nitrogen to which they are attached form an optionally substituted five or six membered ring; provided that at least one of L' and L 2 contain one or more substituents selected from carboxy, sulpho and -P03H2.

The term mono-azo refers to compound with one azo group (-N%W).

2 By "phosphonooxyethylsulphone" is meant a group of the formula S02CH2CH2OPO3H2- Preferably A is N.

R' is preferably H or optionally substituted C,-alkyl, more preferably H, C,,-alkyl or C2,-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 R' is H.

G is preferably attached ortho to the azo group. Preferably G is -S03H, COOH, -CF3, alkyl (preferably optionally substituted C1-4-alkoxy), alkoxy (preferably optionally substituted C1-4-alkyl) or -P031-12, more preferably -S03H, -COOH or -CF3 and especially -S03H.

When R 2, R 3, R' or R' is optionally substituted alkyl it is preferably optionally substituted C1.10-alkyl, more preferably optionally substituted C1-6-alkyl and especially optionally substituted CI-4-alkyl. Preferred optional substituents include, for example hydroxy, carboxy, sulpho, -P031-12, cyano, a 5 or 6 membered heterocyclic group, or a group represented by T, wherein T is an optionally substituted amino group. Especially preferred substituents are selected from hydroxy, carboxy, sulpho, a group represented by T or a 5 or 6 membered heterocyclic group.

Preferred 5 or 6 membered heterocyclic groups are optionally substituted furanyl and tetrahydrofuranyl, more preferably furanyl or tetrahydrofuranyl and especially furan-2-yl and tetra hyd rofu ra n-2-yl.

Preferably T is a group of the formula -NR'R' wherein R' and R' are each independently H, optionally substituted alkyl, -CO(alkyl) -CO(phenyl) or R' and R' together with the nitrogen to which they are attached form an optionally substituted morpholine or piperazine ring.

When R 6 or R 7 is optionally substituted alkyl it is preferably C,-6alkyl optionally substituted by -COOH, -S03H, -OH or -NH2, more preferably it is C,,-alkyl. For example methyl, ethyl, n-propyl and iso-propyl.

When R' or R' is -CO(alkyl) it is preferably -CO(Cl-6-alkyl), more preferably -CO(C,,-alkyl). For example -COCH2CH3 and -COCH2CH2CH3 When R6 and R' together with the nitrogen to which they are attached form a substituted morpholine or piperazine ring it is preferably substituted by C,-4-alkyl, -CO(C,-4-alkyl) or a group of the formula -M-NR'RI where M is an alkylene linking group and R' and R' each independently is H or C,-6-alkyl optionally substituted by a hydroxy, carboxy or C,-,-alkoxy.

M is preferably C1.6-alkylene, more preferably C2-6-alkylene and especially -(CH2)9-, where g is from 2 to 6.

3 Further preferred groups represented by T include -NH2; -NH(C,-6-alkyl), for example ethylamino; -INI(C,-6-alky02, for example di-ethylamino; NHCO(C,-alkyl), for example -NHCOCH3 and -NHCOCH2CH3; morpholino; piperazinyl; and substituted piperazinyl groups of the Formula (2):

-N /-\ N-Y Formula (2) wherein:

Y is C,-4-alkyl, C,-4-hydroxyalkyl, -CO(C1-4-alkyl) or a group of the formula -M-NWIR'; and M, R' and R9 are as hereinbefore defined.

Preferred groups of the Formula (2) include for example:

-N N-(C,,,-alkylene)NH2 -N N-(C,,-alkylene)NH(C,.,,-alkyt) and -N /--\ N-(C1-4-alkyl) A preferred alkyl group substituted by T which may be represented by any of R 2 ' R', R and R' is of the formula -(CdH2d)-T wherein cl is 1 to 6, more preferably 2 to 6 and T is as hereinbefore defined.

A further preferred optionally substituted alkyl group represented by any of R 2, R', R 4 and R 5 is of the Formula (3):

-(C.H2.0)P(CbH2bo)qR" Formula (3) wherein: R p is H or alkyl; a and b are different and from 1 to 6; is from 1 to 4; and q is from 0 to 3.

Preferably WO is H or C,-4-alkyl, more preferably H.

Preferably a and b are each independently 2 to 6, more preferably 2 or 3, p is 1 or 2 and q is 0.

Preferred groups of the Formula (3) include -(C2-,-al kyle ne)O(C2-,-al ky lene) OC, -4alkyl, for example, - C^OC2H4OCH3, -(C2-6-alkylene)O(C2-,-alkylene)OH, for example -C2H40C2H40H, -CH2CH(CH3)CH20C,H40H and-C3H.OC21H140H.

4 When R', R 3, R 4 or R5 is optionally substituted aryl it is preferably optionally substituted phenyl or naphthyl, more preferably optionally substituted phenyl. Preferred optional substituents include for example Cl-6-alkoxy, Cl-6-alkyl, Cl-6-alkyl substituted by hydroxy, carboxy or sulpho, halogen (preferably F or Cl), hydroxy, cyano, carboxy, sulpho, P031-12, nitro, amino, -COC1.4-alkyl or -NI-ICOC1-4-alkyl.

A preferred optionally substituted aryl group is of the formula:

-a wherein:

(R1% R" is C,-alkyl, C,-alkoxy, halogen, carboxy, sulpho or -P031-12; and n is 0 to 5.

n is preferably 0, 1 or 2.

When R 4 and R5 together with the nitrogen to which they are attached form an optionally substituted 5 or 6 membered ring it is preferably an optionally substituted piperazine or morpholine ring. The substituents are preferably selected from hydroxy, carboxy, sulpho, halogen, C,-6-alkoxy, -COC,,-alkyl, C1-6-alkyl and C,-6- alkyl substituted by hydroxy, carboxy, sulpho or a group represented by T as hereinbefore defined. More preferably the substituents are selected fromC,-6-alkyl or a group of the formula -Cl-6-alkylene-T. When R 4 and R' together with the nitrogen to which they are attached form a substituted piperazine ring it is preferably substituted on a nitrogen atom.

It is especially preferred that when R 4 and R5 together with the nitrogen to which they are attached form a 5 or 6 membered ring it is morpholine or piperazine optionally substituted by a group Y as hereinbefore defined.

R', R', R 4 and R' are preferably free from sulphatoethylsulphonyl and vinylsulphone groups.

It is preferred that R', R 3, R4 and R' are each independently H, C,-,alkyl optionally substituted by hydroxy, carboxy, sulpho, -P03H2, a 5 or 6 membered heterocyclic group or a group represented by T, or R 4 and R 5 together with the nitrogen to which they are attached form a morpholine ring or an optionally substituted piperazine ring.

In view of the foregoing preferences, preferred compounds of the Formula (1) are of the Formula (4) and salts thereof:

H 3 R 1 X!-- (-CPH2p)-W' H03s NH2 N N- N- N X-- (_CqH2q) -W 2 OH H03S Formula (4) wherein:

X' and X2 each independently is -0-, -S- or -NR 12_; W1 and W2 each independently is H, carboxy, sulpho, hydroxy, _P03H2, a group T; -OC,-6-alkylene-OR"', C,-6-alkoxy or a 5 or 6 membered heterocyclic group; R 12 is H or C,,-alkyl optionally substituted by hydroxy, carboxy, sulpho or Cl-4-alkoxy; p and q are each independently 1 to 6; T, R1 and R'O are as hereinbefore defined; provided that at least one of W' and W' is sulpho, carboxy or _P03H2.

The compounds of Formula (4) provide prints which exhibit a high lightfastness when incorporated into inks for ink jet printing.

When W' or W' is a 5 or 6 membered heterocyclic group it is preferably piperazinyl, morpholinyl, furanyl or tetrahydrofuranyl group, more preferably it is a tetra hyd rofu ran-2-yl group of the formula:

"0 "In R 12 is preferably H or Cl,-alkyl optionally substituted by hydroxy, carboxy or sulpho. It is especially preferred that R 12 is H.

A first preferred embodiment of the present invention comprises a compound of Formula (4) and salts thereof wherein:

W1 W2 is sulpho or carboxy; is H, hydroxy, a group T, -OCI-6-alkylene-OR", C1-6-alkoxy or a 5 or 6 membered heterocyclic group; or _X2_(C H2,)-W2 form a piperazine or morpholine ring; and Xi, X2, R, R'O, T, p and q are as hereinbefore defined.

The compounds of the invention 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 alkali metal salts are those with sodium.

6 Especially preferred ammonium and substituted ammonium salts have cations of the formula +NQ4 wherein each Q independently is H or optionally substituted alkyl, or two groups represented by Q are H or optionally substituted alkyl and the remaining two groups represented by Q, together with the N atom to which they are attached, form a 5 or 6membered ring (preferably a morpholine, pyridine or piperidine ring).

Preferably each 0 independently is H or Cl_.4kyl, more preferably H, CH3 or CH3CH2, especially H. Thus the cation is preferably ammonium (i.e.+NH4).

Examples of cations include NH,, morpholinium, piperidinium, pyridinium, (CH3)3N+H, (CH3)2N+H2, H2N+(CH3)(CH2CH3),CH3N+H3, CH3CH2WH3, H2W(CH2CHI, CH3CH2CH2WH3, CH3CH2CH2WI-13, (C HICHWH3, N+(CH3)4, W(CH2CHI, N-methyl pyridinium, N,N-dirriethyl piperidinium and N,N-dimethyl morpholinium.

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 compounds of the invention may be prepared using conventional techniques for the preparation of azo dyes. For example a suitable method comprises condensing a compound of the Formula (5) with a compound of the Formula L 2 H:

H03S G L 1 HO 3S NH 2 R' A --\ 1 N" N N--/ N \ / OH 7J Formula (5) N 2- Cl wherein A, R', G, L' and L 2 are as hereinbefore defined.

The condensation is preferably performed in a liquid medium, more preferably an aqueous medium and especially water. Temperatures of 150C to 1000C are preferred, more preferably from 60 to 701C. 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 N-(C,-,alkyi)morpholine, example, N-alkylated heterocycles, for example N-(C,,-alkyl)piperidine, N, N'-di(Cl-4-alkyl)piperazine; 7 tri(C,-4-alkyi)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 (5).

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. Alternatively, 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, ultraffiltration or a combination thereof.

The product of the above process may be converted, if desired, to the NI1,, quatemary ammonium or organic amine salt by the addition of ammonia, ammonium hydroxide, primary, secondary, tertiary or quaternary 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 (5) may be prepared using conventional techniques, for example by:

(1) diazotising the compound of the formula:

G H 2N--1 NHCOCH, wherein G is as hereinbefore defined, to give the corresponding diazonium salt; (2) coupling the diazonium salt from stage (1) with 2-amino-8-naphthol-3,6-disulphonic acid at a pH < 7, preferably at a pH of from 3 to 5; (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:

cl N 1 "N CIAA';CI 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 L'H.

8 is 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 H2S04, 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 HCL Normally at least one mole of diazotisation agent per mole of the amine in stage (1), 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 -50C to 2WC, preferably from 0 to 1 OOC and especially from 0 to 50C.

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 900C.

The compounds of 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.

The compounds of Formula (1) are useful as dyes, especially for the coloration of inks for ink jet printing.

comprising:

(a) from 0.01 to 30 parts of a compound of the Formula (6); and (b) from 70 to 99.99 parts of a medium comprising a mixture of water and an organic solvent, an organic solvent free from water, or a low melting point solid; wherein all parts are by weight and the number of parts of (a)+(b)=100:

According to a second aspect of the present invention there is provided an ink G L 3 HO 3S NH 2 R 1 A 1 N N N N:( L OH S H03 Formula (6) wherein:

L 3 is L' or a labile atom or group; L4 is L 2 or a labile atom or group; A, W, G, L' and L 2 are as hereinbefore defined; provided that at least one of L 3 and L4 contain one or more substituents selected from carboxy, sulpho and -P03H2.

9 When L' or L' is a labile atom or group, it is preferably an atom or group which is bound by a chemical bond to the compound of Formula (6) which is displaceable by a hydroxyl group of cellulose under mildly alkaline aqueous conditions to form a covalent bond between the compound of Formula (6) and cellulose.

Preferred labile atoms and groups represented by L 3 and L" include halogen atoms, for example F and Cl; sulphonic acid groups; thiocyano groups; quaternary ammonium groups, for example trialkylammonium groups and optionally substituted pyridinium groups, for example 3- and 4-carboxy pyridinium groups.

Preferably L 3 is L' and L4 is L 2 as hereinbefore defined.

In the inks according to the second aspect of the present invention the dye of Formula (6) is preferably of Formula (1), more preferably of Formula (4) as hereinbefore defined.

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.

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 200C 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 991 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 Cwalkanols, preferably methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, n-pentanol, cyclopentanol and cyclohexanol; linear amides, preferably dimethy1formamide 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)ethoxylethanol, 2-[2-(2-ethoxyethoxy)-ethoxy]-ethanoI and ethyleneglycol monoallylether; cyclic amides, preferably 2-pyrrolidone, N-methyl-2-pyrrolidone, N-ethyl2-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 amides, especially 2-pyrrolidone, N-methyl-pyrrolidone and N-ethyl-pyrrolidone; diols, especially 1,5-pentane diol, ethyleneglycol, thiodiglycol, diethyleneglycol and triethyleneglycol; and mono- C,,-alkyl and C1_4alkyl ethers of diols, more preferably mono- C1,-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, caprolactarn 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 300 to 2000C, more preferably of from 400 to 1500C, especially from 50 to 1250C. The organic solvent may be water-im miscible, 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 CH2C'2; 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) Wor an alcohol (especially a Cl-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 11 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 C1,-24 chains, and sulphonamides. The dye of Formula (6) may be dissolved in the low melting point solid or may be finely dispersed in it.

The dyes according to 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 composition 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 dye(s) according to the present invention may be, and preferably are, purified to remove undesirable impurities before they are incorporated into inks for ink jet printing. Conventional techniques may be employed for purifying the dyes, for example osmosis and / or dialysis.

A third aspect of the present invention provides a process for printing an image on a substrate comprising applying an ink containing a compound of Formula (6) to the substrate by means of an inkjet printer.

The ink used in this process preferably comprises an ink as defined in the second aspect of the present invention.

The ink jet printer preferably applies the ink to the substrate in the form of droplets which are ejected through a small orifioe onto the substrate. Preferred ink jet printers are piezoelectric ink jet printers and thermal ink jet printers. In thermal ink jet printers, programmed pulses of heat are applied to the ink in a reservoir by means of a resistor adjacent to the orifice, thereby causing the ink to be ejected in the form of small droplets directed towards the substrate during relative movement between the substrate and the orifice. In piezoelectric ink jet printers the oscillation of a small crystal causes ejection of the ink from the orifice.

The substrate is preferably paper, plastic, a textile, metal or glass, more preferably paper, an overhead projector slide or a textile material, especially paper.

12 Preferred papers are plain or treated papers which may have an acid, alkaline or neutral character. Examples of commercially available treated papers include HP Premium Coated Paper (available from Hewlett Packard Inc), HP Photopaper (available from Hewlett Packard Inc), Stylus Pro 720 dpi Coated Paper, Epson Photo Quality Glossy Film (available from Seiko Epson Corp.), Epson Photo Quality Glossy Paper (available from Seiko Epson Corp.), Canon HR 101 High Resolution Paper (available from Canon), Canon GP 201 Glossy Paper (available from Canon), and Canon HG 101 High Gloss Film (available from Canon).

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 composition to the textile material using an ink jet printer; and ii) heating the printed textile material at a temperature of from 500C 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 pretreatment 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.534660Al.

A fifth aspect of the present invention provides an ink jet printer cartridge containing an ink, wherein the ink contains a compound of the Formula (6) as hereinbefore defined. The ink in the ink jet cartridge is preferably 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 Dye (1) was prepared using the process described below:

13 Na03S NI-12 Na03S r_ Na03 N- NaOOC OH N /r N N-- S03Na \- H N Na03SCH,Cl-12CH2S Dye (1) Stage (1): Diazotisation and Couplinq To N-acetyl p-phenylenediamine sulphonic acid (0.5moles) in water (400mi) was added concentrated hydrochloric acid (250mi) and the solution was cooled to 0- 50C. 2N sodium nitrite (250mi) was added dropwise over 5 minutes with stirring. After 15 minutes, excess nitrous acid was destroyed by the addition of sulphamic acid (0.2g). To the resulting suspension was added a solution of 2-amino-8-naphthol-3,6-disulphonic acid (0.5 moles in 600m] of water at pH6) and the pH was adjusted to 4 by the addition of sodium acetate.

The mixture was stirred at 0-511C for 4 hours before being allowed to warm to room temperature.

Stne (ii) Hydrolysis The acetyl group present on the product of stage (i) was removed by alkaline hydrolysis by adding concentrated sodium hydroxide (200mi) to the mixture resulting from stage 1 and heating at 70-800C for 1.5 hours.

After cooling to room temperature, the pH was adjusted to 7 by the addition of concentrated hydrochloric acid. Sodium chloride (20% weightlvolume) was added and the precipitated solid was collected by suction filtration, washed with 30% brine and dried at 700C. Yield 132g (strength 45%). Stne (iii) Condensations The product from stage (ii) (0.12moles) was

dissolved in water (500mi) at pH7. Cyanuric chloride (0.13moles) was dissolved in acetone (300mi) and added dropwise over 10 minutes to the stirred solution at 0-511C. The mixture was stirred for 40 minutes at this temperature before 2-amino-4- sulpho benzoic acid (0.13 moles) dissolved in water (400mi) was added.

Mercaptopropanesulphonic acid (0.12 moles) was added and the reaction mixture was stirred for 4 hours at a temperature of 70 to 800C and a pH of 9. Acetone was added to precipitate the title dye which was collected by suction filtration and washed with more acetone.

14 Staqe Ov) Purification The product of stage (iv) was redissolved in distilled water and dialysed using Visking tubing to a permeate conductivity of below 100pS. The solution was evaporated to dryness. Yield 69.6g.

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.

Ink Jet Printinq Ink 1 was loaded into a Hewlett Packard Deskjet 560c ink jet printer and was printed onto HP Premium Glossy Paper (available from Hewlett Packard Inc. ). The resulting print was a bright magenta (chroma = 70, as measured using an X-Rite Densitometer).

The optical density of the print was 1.98, as measured using an X-Rite densitometer.

The print exhibited good light fastness, with a AE value of 4.6, as measured by an X-Rite Densitometer, and an optical density loss of 14% after 64 hours irradiation in the Atlas Weatherometer.

Examples 2 to 12 Dyes of the general formula H03S NH2 H03S HO 3 S N- OH -N N / \)- L 2 = N were prepared by condensing the product of stage (ii) in Example 1 with the compound of the formula L'H, followed by a further condensation with the compound L 2 H, wherein L1H and L 2 H are shown in Table 1. The dyes had the AE and reflected optical density (ROD) values shown in the final two columns of Table 1.

Table 1

Example L'H L 2 H AE ROD 2 Morpholine 2-amino-4-sulpho- benzoic acid 5.6 1.86 3 HSC3H6SO3H HSC3H6SO3H 0.8 1.28 4 HNC2H4SO3H I-IN(C21-1401-1)2 2.4 1.8 HSC3H6SO3H I-IN(C21-1401-1)2 - - 6 Morpholine HSC3H6SO3H 5.1 2.23 7 HNC2H4SO3H Morpholine - - A "-" in Table 1 indicates that the value was not measured.

Example 8

The inks described in Tables 1 and 11 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 ink may be applied to paper by thermal or piezo inkjet printing.

The following abbreviations are used in Table 1 and ll: PG = propylene glycol DEG = diethylene glycol NIVIP = N-methyl pyrollidone DIVIK = diethyiketone IPA = isopropanol MEOH = methanol 2P = 2-pyrollidone M113K = methylisobutyl ketone P12 propane- 1,2-diol BDL butane-2,3-diol CET cetyl ammonium bromide PHO Na2HP04and TBT tertiary butanol TDG thiodiglycol TABLE 1 -L 0) Dye Dye Water PG DEG NMP DMK NaOH Na IPA MEOH 2P MIBK Content Stearate 2 2.0 80 5 6 4 5 4 3.0 90 5 5 0.2 7 10.0 85 3 3 3 5 1 2.1 91 8 1 1 3-1 86 5 0.2 4 5 1 1.1 81 9 0.5 0.5 9 3 2.5 60 4 15 3 3 6 10 5 4 4 5 65 20 10 3 2.4 75 5 4 5 6 5 7 4.1 80 3 5 2 10 0.3 6 3.2 65 5 4 6 5 4 6 5 1 5.1 96 4 6 10.8 90 5 5 2 10.0 80 2 6 2 5 1 4 3 1.8 80 5 15 2.6 84 11 5 4 3.3 80 2 10 2 6 7 12.0 90 7 0.3 3 6 5.4 69 2 20 2 1 3 3 7 6.0 91 4 5 TABLE 11

Dye Dye Water PG DEG NMP CET TBT TDG BDL PHO 2P P12 Content 2 3.0 80 15 0.2 5 3 9.0 90 5 1.2 5 1.5 85 5 5 0.15 5.0 0.2 7 2.5 90 6 4 0.12 6 3.1 82 4 8 0.3 6 1 0.9 85 10 5 0.2 2 8.0 90 5 5 0.3 2 4.0 70 10 4 1 4 11 4 2.2 75 4 10 3 2 6 10.0 91 6 3 9.0 76 9 7 3.0 0.95 5 6 5.0 78 5 11 6 7 5.4 86 7 7 3 2.1 70 5 5 5 0.1 0.2 O'l 5 0.1 5 4 2.0 90 10 2 2 88 10 5 78 5 12 5 3 8 70 2 8 15 5 7 10 80 8 12 6 10 80 10 -L -4 A R' G wherein:

L' and L' R 2, R', R 4 and R5 18

Claims (15)

CLAIMS 1. A mono-azo compound of Formula (1) and salts thereof:

1 G R L H03S NH2 1 A--\ N N N 11 N N:-( L

2 OH S H03 Formula (1) is N, C-Cl, C-CN or C-N02; is H or optionally substituted alkyl; is sulpho, carboxy, optionally substituted alkyl, optionally substituted alkoxy, -CF3 or _P03H2; are each independently -SR 2, -OR 3 or -NR 4 R'; are each independently H, optionally substituted alkyl or aryl optionally substituted by a group other than vinyl sulphone, sulphatoethylsulphonyl or phosphonooxyethylsulphonyl; or R 4 and R5 together with the nitrogen to which they are attached form an optionally substituted five or six membered ring; provided that at least one of L' and L 2 contain one or more substituents selected from carboxy, sulpho and _P03H2- 2. A compound according to claim 1 wherein G is attached ortho to the azo group.

3.

A compound according to either claim 1 or claim 2 wherein G is sulpho.

4. A compound according to any one of the previous claims wherein A is N.

5. A compound according to any one of the previous claims wherein:

R 2, R 3, R 4 and R' each independently is H, C,.,,-alkyl optionally substituted by hydroxy, carboxy, sulpho, _P03H2, a 5 or 6 membered heterocyclic group or a group represented by T; or R 4 and R' together with the nitrogen to which they are attached form an optionally substituted morpholine ring or an optionally substituted piperazine ring; and 19 T is an optionally substituted amino group.

6. A compound according to any one of the preceding claims of the Formula (4) and salts thereof:

HO, R 1 XI--(-C,H,P-Wl H03S NH2 N N 0 H H03S Formula (4) X 2 (-C q H2q)-W 2 wherein:

12, X1 and X2 each independently is -0, -S- or -NR.

W1 and W2 each independently is H, carboxy, sulpho, hydroxy, -P03H2, a group T; -OC,-6-alkylene-OR'O, C14-alkoxy or a 5 or 6 membered heterocyclic group; R 12 is H or C1-6-alkyl optionally substituted by hydroxy, carboxy, sulpho or C1-4-alkoxy; T is an optionally substituted amino group; p and q are each independently 1 to 6; and R' is as defined in claim 11; provided that at least one of W' and 0 is sulpho, carboxy or -P03H2.

7. A compound according to claim 6 wherein:

W1 is sulpho or carboxy; W2 is H, hydroxy, a group T, -OC,-6-alkyleneOR'O, C,-6-alkoxy or a 5 or 6 membered heterocyclic group; or _X2_(C qH2q)_W2 form a piperazine or morpholine ring; and X1, X2, R', R'O, T, p and q are as defined in claim 6.

8. A compound according to any one of the preceding claims wherein the compound is in the form of an alkali metal, ammonium or substituted ammonium salt.

9. An ink comprising: (a) from 0.01 to 30 parts of a compound of the Formula (6); and (b) from 70 to 99.99 parts of a medium comprising a mixture of water and an organic solvent, an organic solvent free from water, or a low melting point solid; wherein all parts are by weight and the number of parts of (a)+(b)=1 00:

H03S NH 2 R 1 A N N--/ N N N ( L 4 OH h H03S Formula (6) wherein:

L 3 is L' or a labile atom or group; L 4 is L 2 or a labile atom or group; A, W, G, L' and L' are as defined in claim 1; provided that at least one of L 3 and L contain one or more substituents selected from carboxy, sulpho and -P(M2.

10. A process for printing an image on a substrate comprising applying thereto an ink containing a compound of the Formula (6) as defined in claim 9 by means of an ink jet printer.

11. A process according to claim 10 wherein the ink is as defined in claim 9.

12. A paper, an overhead projector slide or a textile material printed with an ink according to claim 9.

13. An ink jet printer cartridge containing an ink, wherein the ink contains a compound of the Formula (6) as defined in claim 9.

14. A compound substantially as hereinbefore described with reference to any one of the examples.

15. An ink substantially as hereinbefore described with reference to any one of the examples.