CA1086312A - Stabilised phthalocyanines - Google Patents

Abstract

Abstract of the Disclosure A copper phthalocyanine derivative having the formula:

Description

`` 1~8E;312 Tlle present invention relates to stabilised phthaloc-~anines.
Phtha]ocyanine pi~nents~ especially copper phthalocyanines, by virtue of their low cost, high strength, brillia~ shades and outstandi~g general fastness properties are of great commercial significance.
In paint and lacquer systems however, phthalocyanine pigments tend to suffer from a defect, namely f`locculation.
; The defect manifests itself especially in non-aqueous systems.
If paints containing flocculating phthalocyanine pigments are applied under different conditions of shear, widely different -~
cclour strengths can be obtained. Similarly, when paints or prillting inks containing flocculating phthalocyanine pigments are stored, the pigment particles tend to aggregate with resulting loss of tinctorial strength and homogeneity of the paint or i~c.
We have now found copper phthalocyanine derivatives which, when --incorporated i~to a phthalocyanine pigment, piovide a phthalocyanine pigment composition having excell~nt flocculation resistance, when incorporated into paint and printing ink media; moreover, the pigmented media exhibit improved flow and other desira~le-pigmentary properties.
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Accordingly~ the present invention provides a copper phthalocyanine derivative having the forn~ula:-;: O - .
- CuPc - [CH2- 0 - C ~ Y ~n :;
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~,, -~D86312 or a mixture tllereof whert~in CuPc represellts the residuc of a copper phthalocyanine n1olecule, Y is an alkyl or alkenyl residue each having froln 8 to 22 carbon atoms, and each being unsubstituted or substituted by one or more hydroxy groups or being interrupted by one or more nitrogen atoms, or Y is an alkoxyaryl- or aralkyloxyaryl,or an alkyl-aralkyloxyaryl residue wherein the alkoxy-,aralkyloxy or alkyl-aralkyloxy moiety contains from 7 to 22 carbon atoms, and n is àn integer from 1 to 8.
Preferably n is 2, 3 or 4.
Alkyl residues Y are derived from saturated acids Y-COOH, and these acids preferably contain from 12 to 18 carbon atoms and especially from 14 to 16 carbon atoms.
Examples of suitable saturated.acids Y-COOII are n-octanoic, iso-octanoic, n-decanoic,n-dodecanoic(lauric)~ n-tetra-decanoic(myristic),n--hexadecanoic (palmitic), n-octadecanoic (stearic), 12-hydroxystearic, n-eicocanoic and n-docosanoic (behenic) acids. In view of their superior anti-flocculation properties residues Y derived from n-tetradecanoic and n-hexadecanoic acids are preferred.

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When Y is an alkenyl residue, it is deri.ved fron an unsaturated acid Y-COOH which preferably contains from 12 to ..
18 carbon atoms. Suitable examples of unsaturated acids Y-COOX include n-octenoic, n-decenoic, n-dodecenoic and olelc acids as ~ell as ethylenically unsaturated, commercially avallable polycyclic acids such as rosin and hydrogenated rosins.
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Ex~mples of alkoxyaryl, aralkyloxy- or alkyl-aralkyloxy_ aryl residues Y are those having the ~ormula:

y~ II

wherein y1 is an allsyl residue containing from ~to 22 carbon atoms or an optiollally alkyl -substituted aralkyl residue. Examples of suitable and preferred all~yl residues y1 are the same as those listed hereinbefore in respect of Y. When Y is an optionally all~yl-substituted aralkyl residue, it may be e.g. a benzyl, methyl-, ethyl-, propyl-, butyl-, hexyl-, octyl-, decyl-, dodecyl- or tetradecyl-benzyl residue. Specific preferred ~xamples of alkoxy, arall~yloxy- or all~yl-aralkyloxy residues OY are hexyloxy, octyloxy, cetylox~y, ben~yloxy and p-dodecylbenzyloxy residues.
The present invention also pro~ides a process of producing the compounds of formula I comprising reacting a chloromethylated copper phthalocyan~ne of formula:-~,'. ...
. CuPc - ~CH2Cl]n IJI
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... -~
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r wherein CuPc and ~ have their previous significance, with , ,~ .

~ an alkali metal salt of an acid having the formula:- -, ~ :
, . .
YCOOM IV

wh~rein Y has its previous significance and M is an alkali ... . .
- metal, preferably sodium, ~ 4 -.

1~86312 The proccss Or the invention may be convenicntly ef~ected by conducting the reaction in an organic solvent e.g. xylene or toluene inert under the reaction conditions, and optionally in the presence of a catalyst such as cetyltrimethyl ammonium bromide. The reaction mixture may be ~orked up in conventional tnallner e.g. by removing the - solvent by steam distillation, filtering the conlpound of formula I and dryillg it.
The starting~materials of formula III and IV are lcnown compounds.
As already premised, the compounds of formula I have value as flocculation stabilisers for phthalocyanine pigments, and thc fl.occulation-stabilised pigment compositions so produced impart improved flow properties into surface coating media containing said pigment compositions.
Accordingly, the present invention further pr(~vides a pigment composition comprising a phthalocyanine pigment susceptible to flocculation and 2-25,especially. 5-15~ by weight, based on the weight of the flocculating phthalocyanine, of a compound of formula I as hereinbefore defined, The present invention still further provides a , composition comprising an organic material and a pigmenting .~.`,?
. proportion of a pigment composition according to this inven~ion, - The phthalocyanine pigment suscept;ible to flocculation may be a metal free or a me'cal- containing pht.halocyanine pigment, Of these~ the latter cla~ss is more important ',~
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for use in this invention, particularly those containing cobalt, l~ickel or~ especially, 2 copper atom.

Pigment compositions accordin~ to this invention may be produced by a variety of methods. Preferably~
however, the compound of formula I may be incorporated into the flocculating phthalocyanine during the conversion of the latter from its crude state i~to its pigmentary form or, if the phthalocyanine is being prepared directly in pigmentary form, during the synthesis of the pigment Alternatively, the pigmentary flocculating phthalocyanine and the compound of formula I may be physically blended together before, during or after incorporation of the pigments into an application medium e.g. a surface coating medium.

The pigment compositions of this invention can also contain natural reslns such as abietic acid or esters thereof, ethyl cellulose, cellulose acetobutyrate~ alkaline earth metal salts of higller fatty acids, fatty amines such as stearylamine or rosinamine~ vinyl chloride/vinyl acetate i ~ .
i< copolymers~ polyacrylonitrile or polyterpene resins.
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~ Organic materials suitable for colouration by the , 1 pigment compositions of the present invention include ~ natural or synthetic polymers or copolymers, coating ..... .
~` compositions for application to the surface of an art;cle and ~ ,.. .
~ I , . .

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printing ink media. Pre~erred organic materials ar(~
paints, lacquers and other surface coating compositions, or tinting compositions for use in such coating cc~mpositions and printing inks.

Pigment compositions of the in~ention containing compow~cls of forlDula I have excellent flocculation resistance ~ihen incor-porated into paint and printing ink media particularly gra~u~e printing ink and paint media, whereby the flow properties of these ~nedia are considerably impro~ed.
e following Examples further illustrate the present invention. Parts and percentages s~own t~lereln are by weight.

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~X~IPL~ 1 84.5 parts of sodiuln stearate were heated i~ 1000 parts of xylene to gi~e a thick paste which was allo~ed to cool to room temperature be~ore the addition of 44.6 parts of cllloro-meth~la~ed copper phthalocyanine (chlorine content 19,9%).
After the mix~ure had been stirred for 1 h~ur, 10 parts o~
GLOQUAT C ( a c~mmercially available quaternary ammonium salt) were added, followed by 250 parts of xylene. The reaction was heated to 120C, stirred for 5 hours at 120C and then al]owed to cool with stirring. 12 parts of 50% aqueous acetic acid were added, follow~d by 1000 parts of water and the xylene was azeotroped off by distillation, water being added a~ -- ;
necessary. The solids were filtered off, reslurried in ethanol, filtered and dried, giving 71.5 parts of a blue r solid having a ch~orine content of 2.8%.
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- ~XAMPLE 2 - 42.5 parts of behenic acid were refluxed in 390 parts of ,: ~
xylene witll 5 par~s of sodium hydroxide dissol~ed in 25 parts of ~- water~ the water being distilled off leaving a suspension of the 'J sodium salt ~f behenic acid in xylene. This was allowred to ~ cool to ~oom temperature before the addition of 2.5 parts Of ., ,.,: ~
- c~tyl trimethyl ammonium bromide and 24.7 parts of chloro-methylated copper phthalocyanine (chlorine content 17.95%).
: The mixture was heated with stirring at 110-120~C for 8 hours,cooled, the xylene azeotroped off with water, the solids filtered off, washed with water followed by methanol and dried : - 8 --'~ : , ''" , . .. .

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giving 57.5 parts of blue solid, ha~ing a chlorine content of 1.5%.

EX~ll'),l~, 3 ~ 0 parts of lauric acid, 8 parts of sodium hydroxide dissol~ed in 25 parts of water~ 350 parts of methyl isobutyl ketone and 150 parts of toluene were refluxed with stirring until no more water was being boilcd off from the reaction.
The mixture ~as then allowed ~o cool to room temperature before the addition of 3.6 parts of cetyl trimethyl al~ionium bro~ide and 30 parts of chloromethylated copper phthalocyanine(chlorine content 17.9 %). Mle reaction mixture l~as refluxed for 8 hoursO
After cooling 12 parts of 50~ aqueous acetic acid were added followed by 500 parts o~ water and the solvent was azeotroped off.
The solid was filtered off, slurried in ethanol, flltered, washed Wit]l water and dri~d~ giving 3~.2 parts of blue solid (chlorine content 5. 60/o) .

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EXA~LE 4 By replacing the lauric acid in Example 3 with 45.6 parts o~ myristic acid~ a similar product can be obtained, with a yield of 43.3 parts~ and a chlorine content of 1.1%.

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, EX~LE 5 ~:, ~}
. By replacing the lauric acid of ~xample 3 with 51.2 parts of palmitic acid, a yield of 49.7 parts of a product having a chlorine content of o . 7% can be obtailled.

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XA~IPIE 7 36.7 parts of oleic acid, 5.2 parts of sodiwn hydroxide dissolved in 20 parts of water, and 500 parts of xylene were refluxed until no more water was being boiled off from -the i ~eaction. After cooling 2.5 parts of cetyl trimethyl ammonium bromide and 22.3 parts of chloromethylated copper phthalocyanine (chlorine content 1g.9%) were added and the reaction heated at 120-130C for 10 hours. After cooling 500 parts of water ~4 - were added followed by 15 parts of 50% acetic acid and the xylene azeotroped off. The solids were filtered off,slurried in éthanol~ filtered; washed with water and dried~ gI~ing a blue solid ( chlorine content 1.8%).
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., EXA~'LPLE 8 ... .
~; 18.4 parts of undecylenic acid, l: parts of sodium hydroxide dissolved in 25 parts of water and 300 parts of xylene were hea~ed at 110-120C until no more water was being boiled off from the reaction. After cooling to room temperature 1 part of cetyl brimethyl ammonium bromide and 19.8 parts of chloro-methylat-ed copper phkhalocyanine ( chlorine content 17.95%) were added an~ the mixture heated to 110-120C with stirring for _ 10 _ .

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8 hours. The reaction was cooled to 50C before the addition of 500 parts of water and the xylene was azeotroped off. The solids were filtered off, washed with water, slurried in 500 parts of l~arm methanol, filtered, waslIed with water and dried, giving 24.~ parts of a blue solid, having a chlorine content of 4- 'j/

EX~IPIE 9 45.1 parts of staybelite resin ( a commercially prepared partially hydrogenated wood rosin with a carboxylic acid group on the molecule), 7.8 parts of potassi~n hydroxide dissolved in 20 parts of water and 750 parts of toluene wer- refluxed ~.~"
until no more water was being boiled off frotn the reaction.
After the mixture had cooled to room temperature 2.5 parts of cetyl trimethyl ammonium bromide and 22.3 parts of chlorometh-,.",~ .
ylated copper ~hthalocyanine ( chlorine content 19.9%) wereadded and heating continued at 100-110C for 10 hours.
After cooling to room temperature 500 parts of water were added and the solvent azeotroped off. The s:olid was filtered off, washed with water, stirred in ethanol, filtered, washed with -water and dried, giving a blue solid having a chlorine content o f 1 . 5% .
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EX~MPI,E 10 .
14.4 parts of n-octanoic acid, 4 parts of sodium hydroxide dissolved in 25 parts of water and 500 parts of toluene were refluxed until no more water was being ~oiled off from the reaction. 3 parts of cetyl-trimethyl ammonium bromide and 21.1 parts of chloromethylated copper phthalocyanine ( chlorine ;*
content 19.60/~) were then added and the mixture refluxed for 16 hours. Aft:er cooling from the boil, 500 parts of water were then added and the toluene azeotroped off. The slurry was drowned into 2000 parts of metllanol, stirred, filtered and the solid washed with water and dried, giving a blue solid having a chlorine content of 3.2/S.
I~XAMPLE 11 ~ y replacing the n-octanoic acid of Example 10by 17 .9 parts of n-decanoic acid a similar product is obtained , having a chlorine content of 2. 9/0 37.2 parts of 12 hydroxy-stearic acid and 5 parts of sodium hydroxide dissolved ln 25 parts of water were refluxed in 500 parts of toluene for 6 hours to remove all water from the reaction. 26.4 parts of chloromethylated copper phthalocyanine ( of chlorine content 17. 30/o) were added ~ogether with 2.5 parts of cetyl trimethyl ammonium bromlde and the reactants were refluxed for 8 hours. 500 parts of water were added and the toluene azeotroped off. The blue solid was washed with methanol~ followed by water and dried~

~o give ~ product having ~ chlorine content of 7 . 40~o, _ 12 _ ~ . ' : , . ' .; '.

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EXA~I~IE 13 24.7 parts of chloromethyla-ted copper phthalocyaninc, 83.2 parts of a 50% solution of 3-dodecylamino-n-butanoic acid as its sodium salt ( com-nercially l~lown as Armeen SZ), and 2.5 parts of cetyl trimethyl ammonium bromide were refluxed in 300 parts of ~ylene to remove all of the water and then refluxed for a further 4 hours. The xylene was then azeotroped off with water and the blue product washed with methanol and water. -- - . - ,. ' , 128 parts of crude copper phthalocyanine were groùnd with 248 parts of anhydrous sodium sulphate, 20 parts of anhydrous sodium acetate and 4 parts of diethyl- - -aniline to give a salt/pigment mixture in which approximately 650~o of ~he copper phthalocyanine was in the alpha form, the remainder being in the beta form. The salt/pigment mixture was refluxed for 5 hours in 1100 parts of isopropanol/
water azeotrope. The slurry w~s then cool~d to 60C and 13.2 parts of the product of ~xample 6 were added, followed by 20 parts of diethylaniline. The slurry was then stirred for 15 minutes before the addition of 1500 parts of water followed by 120 parts of 5N hydrochloric acid. The iso-propanol/water azeotrope was distilled off and the pigment filtered, washed with water and dried, giving a blue phthalocyanine pigment in the beta form.

_ 13 -~81Ei3~2 EX~MPLE 15 By re~lacing the 13.2 parts of the product of ExaInple 6 wlth 13.2 part~ of tl~e product of Example 7 in the procedure of E~ample 14 a similar product can be obtaincd.

.; ~ , By using the process of Example 14 and replacing the product of Example 6 by an equivalent amount of any of the products of Examples 1-5, 8-11 and 13, samples of pigment may be obtained which, like the productsof Examples 14 and 15 are suitable for use in gravure ink and decorative paint coating systems wherein they exhibit superior flow and flocculation resistance when coqnpared with phthalocyanine pigments prepared in a similar manner but without the addition of the respective composition of the invention.

45.25 parts of p-cetyloxybenzoic acid were refluxed in 500 parts by volume of toluene with 5 parts of sodium hydroxide dissolved in 25 parts by volume of water, until no more ~ater was being boiled off from the reaction. 24.7 parts of chloromethylated phthalocyanine ( of chlorine content 17.3%) were then added and the reaction refluxed for 8 hours.

500 parts b~ voiume of water were added and thetoluene distilled off. The product was filtered off, washed - with meth~nol~ followed by water, and dried in ~he oven at 50C, giving 55.8 parts of a blue solid having a chlorine content of 0. 240~o.

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1~363~2 Ex~lrLE 1 7 500 parts of a mixture containing 160 parts of crude copper phthalocyanine, 25 parts of anhydrous sodium acetate, and 310 parts of anhydrous sodi~ sulphate, l~hich had been ground in the presence of diethylaniline so that the mixture ' contained 70% of the copper phthalocyanine in the alpha form ( the remainder being in the beta form) wer,e refluxed ~ith stirring for 5 hours in 1650 parts by volume of isoprcpanol/water~
azeotrope. 15.8 parts of the product of Exan~ple 16 ~ere added with 25 parts by volume of diethylaniline. After 15 minutes 1900 parts by volume of ~rater were added and the isopropanol/water azeotrope distilled off. The slurry was then allowed to cool to 60C before the addition of 150 par-ts of 6N hydrochloric acid. After~a further 30 mins. ~tirring at 60C the solid product was filtered off, washed free of sulphate ions with water, and dried at 60C giving a blue phthalocyanine pigment in the beta form.

29.0 parts o~ 4(p-dodecylbenzyloxy)-benzoic acid, and ~ parts sodium hydroxide dissolved in approximately 20 parts of water, were refluxed in 250 parts xylene until all the water had been azeotroped off. After cooling 15.5 parts of chloromethylated copper phthalocyanine ( of ch;orine content 12.'8~) were added and the reaction refluxed for 16 hours.

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~86312 Water was then addcd and the xylcne was az~otroped off.
The blue solid was fil~ercd off, washed wit}l alcohol, followed by water and dried. The product ha~ a chlorine content of 1, 60/o.

EXA~lPLL 19 t1.4 parts of p~benzyloxybenzoic acid a~d 2 parts of sodium hydroxide, dissolved in 100 parts of water, were re~luxed in 250 parts of xylene until all the water ~ad been azeotroped off. 1 part of cetyl-trimethyl ammonil~ bromide and 10.15 parts of chloromcthylated copper phthaiocyanine ( of chlorine content 2Q.40/~ ) were added and the reaction mixture refluxed for 8 hours.
After co,oling 250 parts of water were added and some of the xylene azeotroped off. The remainder was removed, during filtration and isolation of the blue solid, by washing with methanol, The solid had a chlorine content of 4.150k, :.

EXA~lPLE 20 .- .
By replacing the benzyloxybenzoic acid of Example 19 with 12.5 parts of p-octyloxy benzoic acid a similar product was obtained. ~he product had a-chlorine content of 3.2/~.

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EXA~J.~ 21 ~, By replacing the bcn~yloxy~enzoic acid of Exalllple 19 with 12.1 parts of hexylo~ybenzoic acid a similar product was obtained. The product had a chlorine content of

2.1%.

By using the process of Example 14 and replacing the product of ~xample 6 by an equivalent amount of any of the prod~cts of Examples 16-21, samples of pign~ent may be obtained which are suitable for use in gravure ink and industrial paint coating systems wherein they exhibit superior-flow and flocculation resistance when compared with phthalocyanine pigments prepared in a similar manner but without the addition of the respective pigment composition of the in~ention.

EXA~LE 22 37.2 parts of cuprous chloride and 5.4 parts of dimethylgly~xime were added to 900 parts of dry methanol and the mixture stirred at room ten]perature until a da k brown complex had formed. 192 parts of 95% pure phthalo~
dinitrile, 18 parts of ammonium chloride and 6 parts of 1,2,4-trichloro-3-phenoxy copper phthalocyanine were added and stirring continued at room temperature for 1 hour.
17.4 parts o~` sodium metal and 6 parts of p~ridine, dissolved in 60 parts of dry methanoln are added simultaneously over 1 hour. After a further 1 hour stir at room temperature . , .

~q~863~2 the mixture was refluxed for 8 hours, coolcd to room temperature and treated witll 144 parts of 9~% sulphllric acid for one hour at room temperature followed by 1 hour at reflux. The suspension was then neutralised with aqueous sodium hydroxide; stirred for 30 minutes and then treated with 11 parts oi the product of Example 16 dissolved or well dispersed in diethylaniline. Stirring at room temperature was continued for 1 hour followed by the addition of dilute hydrocllloric acid to adjust the slurry to pHl.
After 15 minutes stirring the.product was filtered of`f`, washed with l!lethanol and cold dilute hydrochloric acid, and finally with water before being dried at 50-60C to give a blue solid which gives a red-shade blue coating in an industrial allsyd-melamine-formaldehyde paint application and wnich gives improved flow and flocculation resistance when compared with the product obtained when the product of Example 16 is omitted from the process of Example 22.

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Claims (14)

What we claim is:

1. A copper phthalocyanine derivative having the formula I

or a mixture thereof wherein CuPc represents the residue of a copper phthalocyanine molecule, Y is an alkyl or alkenyl residue each having from 8 to 22 carbon atoms, and each being unsubstituted or substituted by one or more hydroxy groups or being interrupted by one or more nitrogen atoms, or Y is an alkoxyaryl- or aralkyloxyaryl, or an alkyl-aralkyloxyaryl residue wherein the alkoxy-, aral-kyloxy or alkyl-aralkyloxy moiety contains from 7 to 22 carbon atoms, and n is an integer from 1 to 8.

2. A derivative as claimed in claim 1 wherein n is 2, 3, or 4.

3. A derivative as claimed in claim 1 or 2 wherein Y
is an alkyl residue derived from a saturated acid Y-COOH
containing from 12 to 18 carbon atoms.

4. A derivative as claimed in claim 1 wherein Y is an alkyl residue derived from a saturated acid Y-COOH
containing from 14 to 16 carbon atoms.

- 19 .

5. A derivative as claimed in claim 4 wherein Y is an alkyl residue derived from n-tetradecanoic or n-hexadecanoic acid.

6. A derivative as claimed in claim 1 wherein Y
is an alkenyl residue derived from an unsaturated acid Y-COOH containing from 12 to 18 carbon atoms.

7. A derivative as claimed in claim 1 wherein Y is a residue of formula:- wherein y' is an alkyl residue containing from 7 to 22 carbon atoms or an optionally alkyl-substituted aralkyl residue.

8. A pigment composition comprising a phthalocyanine pigment susceptible to flocculation and 2 to 25% by weight, based on the weight of flocculating phthalocyanine, of a derivative of formula I as defined in claim 1.

9. A pigment composition as claimed in claim 8 wherein the weight of the derivative of formula I is from 5 to 15%
by weight, based on the weight of flocculating phthalocyanine.

10. A pigment composition as claimed in claim 8 wherein the phthalocyanine pigment is a copper phthalocyanine.

11. A pigment composition as claimed in claim 8 wherein the composition also contains a natural resin, ethyl cel-lulose, cellulose acetobutyrate, an alkaline earth metal salt of a fatty acid, a fatty amine, a vinyl chloride/
vinyl acetate copolymer, a polyalkylnitrile or a polyter-pene resin.

12. A composition comprising an organic material and a pigmenting proportion of a pigment composition as claimed in claim 8.

13. A composition as claimed in claim 12 wherein the organic material is a natural or synthetic polymer or copolymer, a coating composition for application to the surface of an article or a printing ink medium.

14. A composition as claimed in claim 13 wherein the organic material is a gravure printing ink or a paint medium.