METHOD OF PRODUCING A POLYMER USING A PIGMENT DISPERSION FIELD OF THE INVENTION

[0001] The disclosed technology relates to a method of producing a pigmented polymer using a pigment dispersion which is stable at elevated temperatures.

SUMMARY OF THE INVENTION

[0002] The present invention relates to a method of producing a polymer using a pigment dispersion that is stable at elevated temperatures, comprising the steps of (1) providing a pigment dispersion containing (a) a solvent, having a boiling temperature (T), wherein the solvent comprises or consists of ethylene glycol or oligomers of ethylene glycol, (b) a pigment, for example, carbon black, and (c) a dispersant, (2) adding a material having a boiling point higher than temperature (T), and (3) heating the dispersion to at least the boiling temperature (T) of the solvent.

[0003] The dispersant used in the present invention comprises a salt of P and X. P is a polyether functionalized polyacid intermediate formed via the reaction of (i) a polyacid Z, (ii) optionally polyether mono-nucleophile C, and (iii) optionally a non-polymeric mono-nucleophile D. X is an alkali metal, an alkaline earth metal, ammonia, an amine or mixtures thereof.

[0004] In the dispersant used in the method described herein, polyacid Z has the formula (A)n-(B)m-(E)t-(G)q. In polyacid Z, A is a carboxylic acid repeat unit having the structure

R is selected from H, CH3, or CH2COOH and R' is selected from H or COOH, with the proviso that R' can only be COOH when R is H. In polyacid Z, B is an alkyl or aryl repeat unit having 2 to 30 carbon atoms, optionally substituted with halides, ethers, or nitro groups, with the proviso that B is substantially free of or is free of acid functionality. Also, in polyacid Z, E is a repeat unit having the structure where R'' is H or CH3, Y is -P(=O)-(OH)k or -S-(=O)2-OH, and W is a direct link between a backbone carbon atom and the P or S atom of Y or hydrocarbylene linking group of 1-7 carbon atoms, which optionally includes ether, ester or amide linking groups, and k is 1 or 2. Also in polyacid Z, G is a repeat unit having the structure

[0005] R '' is H or CH3, J is ethylene oxide or propylene oxide with at least 50% or at least 70% of J being ethylene oxide, L is H or a linear or branched, saturated or unsaturated chain having 1 to 20 carbon atoms, optionally containing a carbonyl group to form an ester with the oxygen atom between J and L, and r is 1 to 100. In polyacid Z, n is 10 - 200 or 20 to 100, m is 0 to 40 or 0 to 20, t is 0 to 20, and q is 0 to 70, with the proviso that n is at least 30% of all repeat units (n + m + t + q). Polyether mono-nucleophile C contains 6 to 70 ethylene glycol repeat units, and, optionally, contains propylene glycol and/or butylene glycol repeat units, with the proviso that at least 50%, or at least 70% of all repeat units are ethylene glycol. The polyether mono-nucleophile C also contains a single alcohol, primary amine, or secondary amine group. The non-polymeric mono-nucleophile D is a linear or branched, saturated or unsaturated alkyl or aryl chain having 1 to 22 carbon atoms and contains a single alcohol, primary amine, or secondary amine group and optionally one or more tertiary amine, halide, or nitro groups with the proviso that D is substantially free of or free of acid groups.

[0006] In polyether functionalized polyacid P, if q is 1 or greater, 0% to 50% of the total moles of repeat unit A are reacted with C or if q is 0, then 10% to 50% of the total moles of A are reacted with C. Also, in polyether functionalized polyacid P, 0% to 30% of the total moles of A is reacted with D. In the dispersant described above, one or more of the carboxylic acid repeat units of A react with polyether nucleophile C and/or non-polymeric nucleophile D to form one or more bonds, where the bonds are selected from (i) an ester bond formed from the reaction product of an alcohol group of polyether nucleophile C and/or non-polymeric nucleophile D with a carboxylic acid repeat unit of A; (ii) salt bonds and/or amide bonds formed from the reaction product of a primary or secondary amine of polyether nucleophile C and/or non-polymeric nucleophile D with a carboxylic acid repeat unit of A; or (iii) imide bonds formed from the reaction product of a primary amine group of polyether nucleophile C and/or non-polymeric nucleophile D with two adjacent carboxylic acids from the same repeat unit A or adjacent repeat unit A.

[0007] The present invention also includes the use of the dispersant described above to provide a stable pigment dispersion at elevated temperatures.

DETAILED DESCRIPTION OF THE INVENTION

[0008] Definitions. To simplify the disclosure, we will use parentheses around “meth” to indicate that a named molecule can optionally include a methyl substituent such as (meth)acrylic acid will refer to methacrylic acid and/or acrylic acid and methyl (meth)acrylate will refer to methacrylate and/or acrylate. We intend that the polyethers used herein can be random or blocky and do not intend for them to limit the polyethers to a single block or blocks of any particular repeat unit. We will use the symbolic representation C(=O)-OH to represent carboxylic acid in any form such as the acid form, the salt form, or if two carboxylic acids are physically adjacent and can form an anhydride ring, the anhydride form. If the C(=O)-OH is adjacent to a nitrogen of an amide linkage we will also anticipate that it can be converted to a C(=O)- as part of an imide. We will use the term hydrocarbyl to describe a hydrocarbon type group with one hydrogen removed. Hydrocarbyl in this specification will mean hydrocarbon like and can include up to one oxygen or nitrogen for every four carbon atoms in the group, but preferably is just carbon and hydrogen atoms. Hydro- carbylene will mean hydrocarbon with two hydrogen atoms removed. Hydro- carbylene will also optionally include up to one oxygen or nitrogen atom for every two carbon atoms in the group, but preferably is just carbon and hydrogen. For the avoidance of doubt, when we are counting carboxylic acid or carbonyl groups, we will count an anhydride of a dicarboxylic acid and an imide as having two carbonyl groups. [0009] The present invention relates to a method of forming a pigment dispersion that is stable at elevated temperatures. The method comprises the steps of (1) preparing a dispersion containing (a) a solvent, having a boiling temperature (T), wherein the solvent comprises or consists of ethylene glycol or oligomers of ethylene glycol, (b) a pigment, and (c) a dispersant, (2) adding a material having a boiling point higher than temperature (T), and (3) heating the dispersion to a temperature that is at least the boiling temperature (T) of the solvent. The invention also includes the use of a dispersant to provide a stable pigment dispersion at elevated temperatures.

[0010] The solvent used in the present invention comprises ethylene glycol or oligomers of ethylene glycol or mixtures thereof. In one embodiment the solvent comprises or consists of ethylene glycol. In another embodiment, the solvent comprises or consists of oligomers of ethylene glycol. Where the solvent comprises or consists of oligomers of ethylene glycol, the oligomers may comprise 2 to 5 repeat units of ethylene glycol. If the dispersion used in the present invention contains one or more other co-solvents, these solvents may be selected from water, alkanols, alkane carboxylic acids and esters of alkane carboxylic acids among other solvents known to those skilled in the art. In one embodiment, the solvent will have a boiling temperature of at least 180°C, or at least 190°C, or at least 195°C, or at least 200°C. For example, ethylene glycol has a boiling temperature of 197°C. In embodiments where mixtures of solvents or oligomers of ethylene glycol are used, the boiling temperature refers to the initial boiling temperature, or the temperature at which any of the components of a mixture boil.

[0011] The dispersant used in the present invention comprises a salt of P and X. where P is a polyether functionalized polyacid intermediate formed via the reaction of (i) a polyacid Z, (ii) optionally polyether mono-nucleophile C, and (iii) optionally a non-polymeric mono-nucleophile D. X is an alkali metal, an alkaline earth metal, ammonia, an amine or mixtures thereof.

[0012] The polyacid Z has the formula (A)n-(B)m-(E)t-(G)q. In polyacid Z, A is a carboxylic acid repeat unit having the structure R is selected from H, CH3, or CH2COOH and R' is selected from H or COOH, with the proviso that R' can only be COOH when R is H. A may be derived from free radically polymerizable unsaturated monomers with one or more carboxylic acid group (such as acrylic, methacrylic, maleic, fumaric, itaconic, mesaconic, or citraconic acids or mixtures thereof).

[0013] B is an alkyl or aryl repeat unit having 2 to 30 carbon atoms, optionally substituted with halides, ethers, or nitro groups, with the proviso that B is substantially free of or is free of acid functionality. For example, B may be derived from a free radically polymerizable monomer containing a carbon-to-carbon double bond without a carboxylic group or acids from sulfur or phosphorus. Such repeat units of B will be from styrene, ethylene, propene, butenes, (meth)acrylate esters of (meth)acrylic acid and Ci-Cis alcohols, and (meth)acrylate hydroxyl ester such as hydroxyl ethyl (meth)acrylate, hydroxyl butyl (meth)acrylate, vinyl acetate, (meth)acrylamides, vinyl substituted heterocyclics such as vinyl pyrrolidinone, vinyl imidazole, vinyl carbazole, 2-vinylpyridine, and 4-vinylpyridine.

[0014] E is a repeat unit having the structure where R'' is H or CH3, Y is -P(=O)-(OH)k or -S-(=O)2-OH, and W is a direct link between a backbone carbon atom and the P or S atom of Y or hydrocarbylene linking group of 1-7 carbon atoms, which optionally includes ether, ester or amide linking groups, and k is 1 or 2. In one embodiment, E is derived from anionic monoethyleni- cally unsaturated monomers containing sulphonic acid groups and/or phosphoric acid groups and/or phosphonic acid groups which may be in the free acid form or salt. As used herein, the term "phosphoric acid group" and "phosphonic acid group" of a phosphorus containing repeat unit refers to a phosphorus oxo acid having a POH moiety in which the hydrogen atom is ionizable. Also included in the term "phosphoric acid group" and "phosphonic acid group" are salts of the phosphorus oxo acid. In its salt or basic form, the phosphorus acid group has a cation such as an alkali earth or alkaline earth metal, an ammonium, substituted ammonium, quaternary ammonium or pyridinium ion replacing at least one acid proton. In its salt or basic form, the sul- phonic acid group has a cation such as an alkali earth or alkaline earth metal, an ammonium, substituted ammonium, quaternary ammonium or pyridinium ion replacing at least one acid proton.

[0015] Examples of anionic monoethylenically unsaturated monomers containing sulphonic acid groups which may be in the free acid form or salt include allylsulfonic acid, methallyl sulfonic acid, styrenesulfonic acid, vinylsulfonic acid, vinyl benzylsulphonic acid, allyloxybenzenesulfonic acid, 2-acrylamido-2-meth- ylethanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-acrylamido-2- methylbutanesulfonic acid, 2-methacrylamido-2-methylethanesulfonic acid, 2-meth- acrylamido-2-methylpropanesulfonic acid, 2-methacrylamido-2-methylbutanesul- fonic acid, acryloyloxymethylsulfonic acid, 2-(acryloyl)oxyethylsulfonic acid, 3-(ac- ryloyl)oxypropyl sulfonic acid, 4-(acryloyl)oxybutylsulfonic acid, methacryloyloxymethylsulfonic acid, 2-(methacryloyl)oxyethylsulfonic acid, 3-(methacry- loyl)oxypropylsulfonic acid, 4-(methacryloyl)oxybutylsulfonic acid, and their salts thereof.

[0016] Examples of anionic monoethylenically unsaturated monomers containing phosphoric or phosphonic acid groups which may be in the free acid form or salt include monovinyl phosphate, monoallyl phosphate, 3-butenylphosphonic acid, mono-3 -butenyl phosphate, mono(4-vinyloxybutyl) phosphate, the phosphate esters of [hydroxyalkyl(meth)acrylates, hydroxy alkyl(meth)acrylamides or their polyalkox- ylate derivatives of molecular weight Mn 150-700 such as 2-hydroxy- ethyl(meth)acrylate, hydroxypropyl(meth)acrylate and 4-hydroxybutyl(meth)acry- late, N-hydroxyethylacrylamide, N-hydroxyethylmethacrylamide hydroxypoly(eth- yleneoxide)(meth)acrylate, and polypropyleneglycol (meth)acrylate], mono(2-hy- droxy-3-vinyloxypropyl) phosphate, mono(l-phosphonoxymethyl-2-vinyloxy ethyl) phosphate, mono(3-allyloxy-2-hydroxypropyl) phosphate, mono(2-allyloxy-l-phos- phonoxymethylethyl) phosphate, their salts and/or esters, especially Cl to C8 monoalkyl, dialkyl and, if appropriate, trialkyl esters, of the monomers containing phosphoric acid and/or phosphonic acid groups. Other suitable phosphonic acid monomers are disclosed in WO 99/25780 Al, and include vinyl phosphonic acid, allyl phosphonic acid, 2-acrylamido-2-methylpropanephosphonic acid, a-phosphonostyrene, 2- methylacrylamido-2-methylpropanephosphonic acid. Further suitable phosphorus functional monomers are 1,2-ethylenically unsaturated (hydroxy)phosphinylalkyl (meth)acrylate monomers, disclosed in US 4,733,005, and include (hydroxy)phos- phinylmethyl methacrylate. One preferred monomer is vinylphosphonic acid, or hydrolyzable esters thereof.

[0017] G is a repeat unit having the structure where R'" is H or CH3, J is ethylene oxide or propylene oxide with at least 50% or at least 70% of J being ethylene oxide, L is H or a linear or branched, saturated or unsaturated chain having 1 to 20 carbon atoms, optionally containing a carbonyl group to form an ester with an oxygen atom between J and L, and r is 1 to 100 or 10 to 50.

[0018] In polyacid Z, n is 10 - 200 or 20 to 100, m is 0 to 40 or 0 to 20, t is 0 to 20, and q is 0 to 70, with the proviso that n is at least 30% of all repeat units (n + m + t + q). In one embodiment, the polyacid Z will be primarily poly(meth)acrylic acid (e.g. > 50% of the repeating units will be conventional repeat unit from polymerizing acrylic acid). In one embodiment, the polyacid will include from 5 to 50 number percent of repeating units from maleic acid or a maleic anhydride. In another embodiment, the polyacid Z may include a variety of copolymers such as poly(meth)acrylic-co-maleic acid; polyacrylic-co-itaconic acid; polyacrylic-co- AMPS acid, polyitaconic-co-acrylate acid; polyitaconic-co-acrylamide acid; etc. in place of poly(meth)acrylic acid

[0019] Polyether mono-nucleophile C contains 6 to 70 ethylene glycol repeat units, and, optionally, contains propylene glycol and/or butylene glycol repeat units, with the proviso that at least 50%, or at least 70% of all repeat units are ethylene glycol. In one embodiment, C contains from 1 to 15 or even 1 to 10 propylene glycol repeat units. The polyether mono-nucleophile C also contains a single alcohol, primary, amine, or secondary amine group.

[0020] Polyether mono-nucleophile may be derived from a poly(alkyleneox- ide) monoalkyl ether monoamine. Exemplary monoamine compounds of this type are commercially available as the Surfonamine® or Jeffamine™ amines from Huntsman Corporation. Specific examples of Surfonamine® amines are L-100 (propylene oxide to ethylene oxide mole ratio of 3: 19), L-207 (propylene oxide to ethylene oxide mole ratio of 10:32), L-200 (propylene oxide to ethylene oxide mole ratio of 3:41), L-300 (propylene oxide to ethylene oxide mole ratio of 8:58).

[0021] When C contains a single alcohol group, C may be derived from a poly(alkyleneoxide) monoalkyl ether. These mono-alkyl ethers are available from a variety of sources such as Sigma-Aldrich, Croda, BASF, Dow, and Ineos.

[0022] The non-polymeric mono-nucleophile D is a linear or branched, saturated or unsaturated alkyl or aryl chain having 1 to 22 carbon atoms and contains a single alcohol, primary amine, or secondary amine group and optionally one or more tertiary amine, halide, or nitro groups with the proviso that D is substantially free of or free of acid groups.

[0023] In some embodiments where non-polymeric mono-nucleophile D contains a primary amine, the primary amine may include methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, 2- ethylhexyl amine, nonylamine, decylamine, undecylamine, dodecylamine, tridecyl amine, tetradecylamine, pentadecylamine, hexadecylamine, heptadecylamine, octadecylamine, nonadecylamine, eicosylamine, or mixtures thereof.In some embodiments, the amine may include benzyl amine, 2-phenylethanamine (often referred to as phenylethyl amine), 3- phenylpropanamine, 4-phenylbutanamine, or mixtures thereof. In one embodiment, the primary amine may include benzyl amine or 2- phe- nylethanamine. In one embodiment, the primary amine of formula R ⁴ -NH2, may include 2-phenylethanamine.

[0024] In some embodiments where non-polymeric mono-nucleophile D contains a secondary amine, the secondary amine may be, for example, dimethyl amine, diethyl amine, dipropyl amine, dibutyl amine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, N,N-diisopropylamine, N,N- diisobutylamine, diisoamylamine, piperidine, N,N-dimethylpiperidin-4-amine, N,N- dibenzylamine, N-benzylmethylamine, N-phenyl-N-propylamine, N-methyl-phene- thylamine, N-methyl-N-(l-phenylethyl)amine, 4-Bromo-N-methylbenzylamine, or 4-Fluoro-N-methylbenzylamine. [0025] Specific examples of suitable mono-functional nucleophiles D containing a hydroxyl functionality include alcohols with optionally substituted Cl-22 hy- drocarbylene groups such as methanol, ethanol, propan- l-ol, propan-2-ol, butanol, isobutanol, neopentyl alcohol, hexanol, octan-l-ol, 2-ethylhexanol, decanol, dodecanol, oleyl alcohol, stearyl alcohol, behenyl alcohol, cyclohexanol, benzyl alcohol, phenol, octylphenol, nonylphenol, phenylethanol, fluorinated alcohols such as lH,lH,2H,2H-perfluoro-l -decanol, C8-22 branched alcohols available under the trademark Isofol™ (ex Sasol).

[0026] The polyacid Z may be prepared by processes known to a skilled person and functionalized with the polyether mono-nucleophile C and, optionally, non-pol- ymeric nucleophile D, by any method known in the art. For example, the polyacid may be prepared by esterification or amidation of poly(meth)acrylic acid or poly(meth)acrylic acid/maleic acid copolymer, or polymerization of (meth)acrylic acid with (meth)acrylic esters and/or amides or polymerization of (meth)acrylic acid with maleic acid (or maleic anhydride), (meth)acrylic esters and/or amides and maleic acid esters and/or amides by any known polymerization technique or a combination of polymerization techniques using a bulk, solution, suspension or emulsion process. The polymerization may comprise of a radical, anionic, cationic, atom transfer or group transfer polymerization process or combinations thereof.

[0027] In the dispersant described herein, one or more of the carboxylic acid repeat units of A react with, polyether nucleophile C and/or non-polymeric nucleophile D to form one or more bonds, where the bonds are selected from (i) an ester bond formed from the reaction product of an alcohol group of polyether nucleophile C and/or non-polymeric nucleophile D with a carboxylic acid repeat unit of A; (ii) salt bonds and/or amide bonds formed from the reaction product of a primary or secondary amine of polyether nucleophile C and/or non-polymeric nucleophile D with a carboxylic acid repeat unit of A; or (iii) imide bonds formed from the reaction product of a primary amine group of polyether nucleophile C and/or non-polymeric nucleophile D with two adjacent carboxylic acids from the same repeat unit A or adjacent repeat unit A.

[0028] In another embodiment, the polymer intermediate P may be obtained or obtainable by reacting polyacid Z (typically with a number average molecular weight between 700 to 50,000, or 700 to 28,000), either as an aqueous solution or a solid with polyether mono-nucleophile C and, optionally, non-polymeric nucleophile D, optionally in the presence of a catalyst, such as an acid or base catalyst. In one embodiment of polymer intermediate P, if q is 1 or greater, 0% to 50% of the total moles of repeat unit A are reacted with C. In another embodiment of polyether intermediate P, if q is 0, then 10% to 50% of the total moles of A are reacted with C.In one embodiment, 0% to 30%of the total moles of A is reacted with D. Polymer intermediate P is subsequently reacted with X weight ratio of the P to X of 30: 1 to 1 : 1 or 15: 1 to 1 : 1 to form a salt. The reactions described herein are performed under conditions that would be known and understood to be useful by those skilled in the art.

[0029] The dispersant used in the present invention comprises a salt of P and X. X is an alkali metal, an alkaline earth metal, ammonia, an amine or mixtures thereof.

[0030] In some embodiments, the salt may be formed by using ammonia, an amine, quaternary ammonium or pyridinium cation as X. Examples of amines are methylamine, diethylamine, ethanolamine, diethanolamine, hexylamine, 2-ethylhex- ylamine and octadecylamine. The quaternary ammonium cation may be a quaternary ammonium cation or a benzalkonium cation. The quaternary ammonium cation may contain one or two alkyl groups containing from 6 to 20 carbon atoms. Examples of quaternary ammonium cations are tetraethyl ammonium, N-octadecyl-N,N,N-trime- thyl ammonium; N,N-didodecyl-N,N-dimethyl ammonium, N-benzyl-N,N,N-trime- thyl ammonium and N-benzyl-N-octadecyl-N,N-dimethyl ammonium cation.

[0031] In other embodiments, the salt may be formed by using an alkali metal or alkaline earth metal as X. For example, monovalent alkali metals (Li, Na, K, Rb, Cs, and Fr) or divalent alkaline earth metals (Be, Mg, Ca, Sr, Ba, and Ra) may be used. In some exemplary embodiments, lithium, sodium and potassium may be used. [0032] In another embodiment, X can be a polyamine such as poly(vinyla- mine), alkylenepolyamine, or polyallylamine or poly(C2-6-alkyleneimine), for example, in one embodiment, polyethyleneimine. The polyamine or polyalkyleneimine may be linear or branched. The polyamine or polyalkyleneimine may have a number average molecular weight of from 140-100, OOOg/mole; more desirably from 140 to 75,000; or preferably from 200 to 10,000 or 20,000. In some embodiments, X may have a total of at least four primary and/or secondary amine groups per molecule and more desirably at least six primary and/or secondary amine groups.

[0033] Examples of polyamines that may be used as X in the present invention may include but are not limited to: amino-functional polyamino acids such as poly(ly- sine) from Aldrich Chemical Co.; amino-functional silicones which are available under the trade name Tegomer® ASi 2122 from Degussa AG; poly amidoamines which are available under the trade names Polypox®, Aradur® or "Starburst®" dendrimers from Aldrich Chemical Co.; polyallylamines and poly(N-alkyl)allylamines which are available under the trade names PAA from Nitto Boseki; polyvinylamines which are available from Mitsubishi Kasei and under the trade name Lupamin® from BASF AG; polyalkyleneimines, such as polyethyleneimines, which are available under the trade names Epomin® (Nippon Shokubai Co., Ltd.) and Lupasol® (BASF AG); and polypropyleneimines, which are available under the trade name Astramol® from DSM AG. Linear polyethyleneimine may be prepared by the hydrolysis of poly(N- acyl) alkyleneimines as described, for example, by Takeo Saegusa et al in Macromolecules, 1972, Vol 5, page 4470. Polypropyleneimine dendrimers are commercially available from DSM Fine Chemicals and poly(amidoamine) dendrimers are available as “Starburst” dendrimers from Aldrich Chemical Company. Alkylenepolyamines may be characterized as having less than two, usually less than 1% (by weight) material boiling below about 200°C and include still bottoms such as ethylene polyamine still bottoms obtained from the Dow Chemical Company of Freeport, Texas [0034] When X is a polyimine, in one exemplary embodiment, it is poly (C2-6- alkyleneimine) or polyethyleneimine (PEI). The polyimine may be linear or especially branched.

[0035] As both P and X may have multiple co-reactive groups, in some cases, there may be more than one bond (as defined above) between them. It is also acknowledged that more than one P can be bonded to a single X. Similarly, there can be more than one X chemically bonded to a single P.

[0036] In the dispersant used in the present invention, polymer intermediate P and species X are reacted together such that -CO2H or -CCL" of P reacts with the amine, metal, or other basic groups of X to give ionic salt bonds and/or covalent bonds or a mixture of ionic salt bonds and covalent bonds. The weight ratio of P to X 30: l to 1 : 1, or 15: 1 to 1 : 1, or 14: 1, 13 : 1, 12: 1, 11 : 1, 10: 1, 9: 1, 8: 1, 7: 1, 6: 1, 5: 1, 4: 1, 3 : 1, or 2: 1.

[0037] In one embodiment, the reaction product or co-polymer product of P and X may be presented as a neat polymer or a polymer in an organic solvent. This can be achieved by dissolving the neat reaction product or co-polymer product into the solvent, or by carrying out the synthesis of the reaction product or co-polymer product in the solvent. In one embodiment, the solvent comprises or consists of ethylene glycol, oligomers of ethylene glycol, or mixtures thereof.

[0038] In some embodiments, the reaction product of P and X can be further functionalized to adapt their properties and application performance to specific requirements. The modification reactions below may be combined where necessary, to give multiply modified polyacid polybasic addition compounds. Where two or more modifying reactions are to be carried out in succession, it should be ensured that enough groups are available that are reactive for one or more subsequent reactions in the molecule.

[0039] The stated modifications are advantageous embodiments of the present invention and can be realized by: a) reaction of one or more of the remaining free amino groups of the aminic polybasic species with isocyanates, lactones, anhydrides, epoxides, cyclic carbonates, or (meth)acrylates; b) salification and/or reaction of one or more of the remaining free amino groups of the aminic polybasic species with mono or polycarboxylic acids, mineral acids, phosphorus and polyoxometallate containing acids or strong acids; c) oxidation of one or more of the of the remaining free amino groups of the aminic polybasic species to nitrogen oxides; d) quaternization of one or more of the remaining free amino groups of the aminic polybasic species; or e) reaction of one or more of the remaining free amino groups of the aminic polybasic species with one or more mono amino-reactive group terminated polymer(s) of MW 150 - 3000. [0040] The modification of any remaining amino groups may take place in a way which is known to the skilled person. For example, salification and quaterniza- tion of the amino nitrogen atom can be achieved using mineral acids, strong acids, alkyl sulfates, alkyl or aralkyl halides, halocarboxylic esters, alkyl oxalates or epoxides. Such quaternization is preferred when, for example, amino groups will react with a binder system into which the pigment paste is incorporated and cause flocculation. Suitable reagents for this purpose include hydrochloric acid, acetic acid, sulphuric acid, alkyl sulphonic acids, alkyl hydrogen sulphates or aryl sulphonic acids. Quaternizating agents include dimethyl sulphate, benzyl chloride, methyl halides such as chlorine, bromine and iodine, dimethyl oxalate, ethylene oxide, propylene oxide and styrene oxide in the presence of acids, and propane (or butane) sultone.

[0041] Salification and/or reaction of one or more of the remaining free amino groups of the aminic polybasic species with mono or polycarboxylic acids or phosphorus containing acids are disclosed in JP9,157,374, US2010/0017973 and US2013/0126804. Specific examples of suitable mono carboxylic acids include optionally substituted C1-50 aliphatic monocarboxylic acids such as acetic acid, propionic acid, caproic acid, caprylic acid, 2-ethylhexanoic acid, nonanoic acid, decanoic acid, lauric acid, myristic acid, palmitic acid, oleic acid, linoleic acid, stearic acid, arachidic acid, erucic acid, behenic acid, methoxyacetic acid, mixtures of fatty acids derived from oils from naturally occurring sources such as sunflower oil, rape seed oil, castor oil and olive oil, branched alkyl carboxylic acids available under the trademark Isocarb™ (ex Sasol), Unicid™ acids which are linear C25-50 synthetic primary acids commercially available from Baker Hughes and aromatic carboxylic acids such as benzoic acid, salicylic acid and naphthoic acid. Specific examples of suitable polycarboxylic acids include succinic acid, malonic acid, adipic acid, sebacic acid, malic acid, fumaric acid, citric acid and tartaric acid. Specific examples of suitable phosphorus containing acids include phosphoric acid and phosphorous acid. Specific examples of suitable poly oxometallate containing acids include phosphomolybdic acid, phosphotungstic acid and silicomolybdic acid.

[0042] Reaction of one or more of the remaining free amino groups of the aminic polybasic species with anhydrides are disclosed in US6,878,799 and US7,767, 750. Specific examples of suitable anhydrides include maleic anhydride, succinic anhydride, phthalic anhdride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, trimellitic anhydride, Ci -20 alkenyl and alkyl succinic anhydrides.

[0043] Reaction of one or more of the remaining free amino groups of the aminic polybasic species is disclosed in JP4, 031,471. Specific examples of suitable epoxides include styrene oxide, propylene oxide and ethylene oxide.

[0044] Reaction of one or more of the remaining free amino groups of the aminic polybasic species abd carboxylic acid, sulfonic acid, sulfuric acid, phosphonic acid, phosphoric acid, isocyanate, epoxide, (meth)acrylate, acetoacetoxy or cyclocarbonate terminated polymers. The reaction products can be in the form of an amide and/or the corresponding salt when a carboxylic acid terminated polymer is used, a salt when sulfonic acid, sulfuric acid, phosphonic acid and phosphoric acid terminated polymers are used and a covalent bond is formed between the NH functionality of the amino group and i) an isocyanate terminated polymer to give a urea, ii) an epoxide terminated polymer to ring open the epoxy group giving an amino alcohol, and iii) a (meth)acrylate terminated polymer via a Michael addition across the double bond. These mono-reactive terminated polymers can be based on polyesters, polyethers, polyether/polyester, polyamide, polyesteramide, poly(meth)acrylates, polyurethanes and mixtures thereof. Particularly useful mono-reactive polymers have been disclosed in various patents.

[0045] Suitable examples of carboxylic acid terminated polyester, polyesteramide and polyamide polymers are disclosed in US4,224,212, US4,861,380, US5,700,395, US5,760,257, US6, 197,877, US8,202,935, JP4,866,255, JP8,010,601, JP9, 157,361, W02006/113258 and W02007/039605 in which; a) the polyesters are derived from the polymerisation of:- one or more of a hydroxycarboxylic acid and/or a lactone optionally in the presence of initiator molecules containing a carboxylic acid or ester functionality; or one or more of a diol with one or more of a dibasic acid/ anhydride optionally in the presence of initiator molecules containing a carboxylic acid or ester functionality; b) the polyesteramides are derived from the polymerisation of:- one or more of a hydroxycarboxylic acid and/or a lactone with one or more of an aminocarboxylic acid and/or a lactam optionally in the presence of initiator molecules containing a carboxylic acid or ester functionality; and c) the polyamides are derived from the polymerisation of - one or more of an aminocarboxylic acid and/or a lactam optionally in the presence of initiator molecules containing a carboxylic acid or ester functionality; or one or more of a diamine with one or more of a dibasic acid/anhydride optionally in the presence of initiator molecules containing a carboxylic acid or ester functionality. [0046] Specific examples of suitable hydroxy carboxylic acids and lactones include ricinoleic acid, 12-hydroxystearic acid, 6-hydroxy caproic acid, 5-hydroxy valeric acid, 12-hydroxy dodecanoic acid, 5-hydroxy dodecanoic acid, 5-hydroxy decanoic acid, 4-hydroxy decanoic acid, 10-hydroxy undecanoic acid, lactic acid, glycolic acid, P-propiolactone, P-butyrolactone, optionally Ci-6-alkyl substituted s-ca- prolactone and optionally Ci-6-alkyl substituted 6-valerolactone such as s-caprolac- tone and the 7-methyl-, 3-methyl-, 5-methyl-, 6-methyl-, 4-methyl-, 5 -tetra-butyl-, 4,4,6-trimethyl- and 4,6,6-trimethyl- s-caprolactone, 6-valerolactone, P-methyl-6- valerolactone or mixtures thereof.

[0047] Specific examples of suitable diols include alkylene glycols such as ethylene glycol, propylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, diols with ether linkages such as diethylene glycol, dipropylene glycol, tripropylene glycol and tri ethylene glycol. Examples of suitable polyalkylene glycols include polyethylene glycols, polypropylene glycols, polybutylene glycols, mixed block and random copolymers of polyethylene glycol and polypropylene glycol (Pluronic and reverse pluronic ex BASF) with MW less than 1000.

[0048] Specific examples of suitable dibasic acids and anhydrides include maleic anhydride, succinic anhydride, glutaric anhydride, fumaric acid, malonic acid, adipic acid, sebacic acid, phthalic anhydride, and cyclohexane dicarboxylic anhydride.

[0049] Specific examples of suitable aminocarboxylic acids include sarcosine, beta-alanine, 4-aminobutyric acid, 6-aminocaproic acid and 11-aminoundecanoic acid. [0050] Specific examples of suitable lactams include laurolactam and caprolactam.

[0051] Specific examples of suitable diamines include alkylene diamines such as ethylenediamine, 1,2-propylenediamine, 1,3-propylene diamine, the isomeric butylenediamines, pentanediamines, hexanediamines, heptanediamines, 1,12-diamino- dodecane, diaminocyclohexanes, and diamines with ether linkages such as 1 ,2-bis(2- aminoethoxy)ethane. Examples of suitable polyetherdiamines include Jeffamine diamines commercially available from Huntsman such as D230, D400, ED600.

[0052] Examples of suitable initiator molecules containing a carboxylic acid or ester group include optionally substituted C1-50 aliphatic monocarboxylic acids as described above and their methyl or ethyl esters.

[0053] Suitable examples of phosphate, sulphate and sulphonate terminated polyester polymers are disclosed in US4,861,380 and US6, 197,877 in which the polyesters are derived from the polymerisation of hydroxycarboxylic acids and/or lactones as disclosed above using initiator molecules containing a hydroxyl or amino functionality. Specific examples of suitable initiator molecules containing a hydroxyl functionality include alcohols with optionally substituted Cl-50 hydrocarbylene groups such as methanol, ethanol, propan- l-ol, propan-2-ol, butanol, isobutanol, neopentyl alcohol, hexanol, octan-l-ol, 2-ethylhexanol, decanol, dodecanol, oleyl al- chol, stearyl alcohol, behenyl alcohol, cyclohexanol, benzyl alcohol, phenol, octylphenol, nonylphenol, phenylethanol, fluorinated alcohols such as 1H,1H,2H,2H- perfluoro-1 -decanol, C8-36 branched alcohols available under the trademark Isofol™ (ex Sasol), Unilin™ alcohols which are linear C25-50 synthetic primary alcohols commercially available from Baker Hughes. Specific examples of suitable initiator molecules containing an amino functionality include amines such as butylamine, dodecylamine, stearylamine.

[0054] Suitable examples of (meth)acrylate terminated polyester, polyesteramide and polyamide polymers are disclosed in EP713894, JP3,488,001, JP2010222522 and US8,202,935 in which the polyesters are derived from the polymerisation of hydroxy carboxylic acids and/or lactones as disclosed above using:- i. initiator molecules such as 2-hydroxyethylacrylate directly; ii. initiator molecules containing a hydroxyl functionality then subsequent transesterification reaction with a (meth)acrylate ester; iii. initiator molecules containing a carboxylic acid or ester functionality as described above and then subsequent reaction with a (meth)acrylate ester containing a hydroxyl functionality such as 2-hydroxyethylacrylate or an epoxy functionality such as glycidyl methacrylate.

[0055] Suitable examples of phosphate, sulphate and sulphonate terminated polyether, polyether/polyester, polyether/polyurethane and polyether/polyester/poly- urethane polymers are disclosed in US5, 130,463, US5,151,218, US6,l l l,054, US6,310,123, US7,595,416 and US8,202,935 in which the polyethers are derived from the polymerisation of alkylene and alkarylene oxides such as ethylene oxide, propylene oxide, butylene oxide and styrene oxide using initiator molecules containing a hydroxyl or amino functionality as disclosed above. These polyether mono alcohols can be further reacted with one or more hydroxy carboxylic acids or lactones as disclosed above or with diols and diacids as described above to give the polyether polyester polymers containing an alcohol group which can then be phosphated as disclosed in US5, 130,463. The polyether mono alcohols and polyether polyester monoalcohols can be reacted further with diols as disclosed above in combination with diisocyanates to give polyether polyurethane and poly ether polyester polyurethane polymers respectively containing an alcohol group which can then be phosphated as disclosed in US5, 130,463. Specific examples of suitable diisocyanates include hexamethylenediisocyanate (HDI), 2,4- and 2,6-toluenediisocyanate (TDI) , isophoronediisocyanate (IPDI), a,a-tetramethylxylene diisocyanate (TMXDI), di- phenylmethane-4, 4 -diisocyanate (4,4’ -MDI), diphenylmethane-2, 4 -diisocyanate (2,4’ -MDI) and di cyclohexylmethane-4, 4 -diisocyanate (HMDI)

[0056] Suitable examples of (meth)acrylate terminated polyether polymers are disclosed in US7,923,474 and JP2010222522.

[0057] Suitable examples of carboxylic acid terminated polyether polymers are disclosed in JP4,248,207, US7,767,750, US7,671,119, US7, 872,070, US8,076,409 and US8, 168,713 in which polymers are derived from i) the reaction of polyalkyleneglycol mono substituted ethers with halocarb oxy late salts such as sodium monochloroacetate and then acidified using hydrochloric acid; ii) the reaction of polyalkyleneglycol mono substituted ethers with acrylonitrile and then hydrolysed in the presence of acids such as hydrochloric acid; and iii) the reaction of polyetheramines with anhydrides.

[0058] Suitable examples of isocyanate terminated polyester and polyether polymers are disclosed in JP4,031,471, JP7, 149,855 and W02007/039605. Suitable examples of epoxide or acetoacetoxy or cyclocarbonate terminated polyacrylate polymers are disclosed in US5,100,969.

[0059] The dispersion used in the present invention also includes one or more pigments or other particulate solid material. In one embodiment, the solid is an organic pigment from any of the recognised classes of pigments described, for example, in the Third Edition of the Colour Index (1971) and subsequent revisions of, and supplements thereto, under the chapter headed “Pigments”. Examples of organic pigments are those from the azo, disazo, trisazo, condensed azo, azo lakes, naphthol pigments, anthanthrone, anthrapyrimidine, anthraquinone, benzimidazolone, carbazole, diketopyrrolopyrrole, flavanthrone, indigoid pigments, indanthrone, isodibenzanthrone, isoindanthrone, isoindolinone, isoindoline, isoviolanthrone, metal complex pigments, oxazine, perylene, perinone, pyranthrone, pyrazoloquinazolone, quin- acridone, quinophthalone, thioindigo, triarylcarbonium pigments, triphendioxazine, xanthene and phthalocyanine series, especially copper phthalocyanine and its nuclear halogenated derivatives, and also lakes of acid, basic and mordant dyes. Carbon black, although strictly inorganic, behaves more like an organic pigment in its dispersing properties. In one embodiment, the organic pigments are phthalocyanines, especially copper phthalocyanines, monoazos, disazos, indanthrones, anthranthrones, quinacridones, diketopyrrolopyrroles, perylenes and carbon blacks.

[0060] Examples of inorganic pigments include metallic oxides such as titanium dioxide, rutile titanium dioxide and surface coated titanium dioxide, titanium oxides of different colours such as yellow and black, iron oxides of different colours such as yellow, red, brown and black, zinc oxide, zirconium oxides, aluminium oxide, oxy-metallic compounds such as bismuth vanadate, cobalt aluminate, cobalt stannate, cobalt zincate, zinc chromate and mixed metal oxides of two or more of manganese, nickel, titanium, chromium, antimony, magnesium, cobalt, iron or aluminium, Prussian blue, vermillion, ultramarine, zinc phosphate, zinc sulphide, molybdates and chromates of calcium and zinc, metal effect pigments such as aluminium flake, copper, and copper/zinc alloy, pearlescent flake such as lead carbonate and bismuth oxychloride.

[0061] Inorganic solids include extenders and fillers such as ground and precipitated calcium carbonate, calcium sulphate, calcium oxide, calcium oxalate, calcium phosphate, calcium phosphonate, barium sulphate, barium carbonate, magnesium oxide, magnesium hydroxide, natural magnesium hydroxide or brucite, precipitated magnesium hydroxide, magnesium carbonate, dolomite, aluminium trihydroxide, aluminium hydroperoxide or boehmite, calcium and magnesium silicates, aluminosilicates including nanoclays, kaolin, montmorillonites including bentonites, hectorites and saponites, mica, talc including muscovites, phlogopites, lepidolites and chlorites, chalk, synthetic and precipitated silica, fumed silica, metal fibres and powders, zinc, aluminium, glass fibres, refractory fibres, carbon black including single- and multi-walled carbon nanotubes, reinforcing and non-reinforcing carbon black, graphite, Buckminsterfullerenes, asphaltene, graphene, diamond, alumina, quartz, silica gel, wood flour, wood flake including soft and hard woods, saw dust, powdered paper/fibre, cellulosic fibres such as kenaf, hemp, sisal, flax, cotton, cotton linters, jute, ramie, rice husk or hulls, raffia, typha reed, coconut fibre, coir, oil palm fibre, kapok, banana leaf, caro, curaua, henequen leaf, harakeke leaf, abaca, sugar cane bagasse, straw, bamboo strips, wheat flour, MDF and the like, vermiculite, zeolites, hydrotalcites, fly ash from power plants, incinerated sewage sludge ash, pozzolanes, blast furnace slag, asbestos, chrysotile, anthophylite, crocidolite, wollastonite, attapulgite and the like, particulate ceramic materials such as alumina, zirconia, titania, ceria, silicon nitride, aluminium nitride, boron nitride, silicon carbide, boron carbide, mixed silicon-aluminium nitrides and metal titanates; particulate magnetic materials such as the magnetic oxides of transition metals, often iron and chromium, e.g., gamma-Fe2O3, FesC , and cobalt-doped iron oxides, ferrites, e.g., barium ferrites; and metal particles, for instance metallic aluminium, iron, nickel, cobalt, copper, silver, gold, palladium, and platinum and alloys thereof.

[0062] Other useful solid materials include flame retardants such as pentabromodiphenyl ether, octabromodiphenyl ether, decabromodiphenyl ether, hexabromocyclododecane, ammonium polyphosphate, melamine, melamine cyanu- rate, antimony oxide and borates.

[0063] In one particular embodiment of the invention, the pigment comprises or consists of carbon black.

[0064] The dispersion of the present invention may be prepared by methods known and understood by those skilled in the art. In some embodiments, the dispersion used in the methods of the present invention comprises 0.5% to 40% by weight pigment, 0.5% to 40% by weight of the dispersant described herein, and 20% to 99% by weight solvent. Small amounts of other additives may be included in the dispersion as described herein and understood to those skilled in the art. In one embodiment, the solvent is primarily or solely ethylene glycol. In another embodiment, the solvent is primarily or solely oligomers of ethylene glycol having 2 to 5 repeat units of ethylene glycol.

[0065] In one embodiment, the dispersant used in the methods of the present invention has a pH of greater than or equal to 5, or even greater than or equal to 7, when measured in a 50% solution of the dispersant in ethylene glycol.

[0066] After preparing the dispersion comprising the solvent, dispersant, and pigment (all as described above), the method of the present invention further includes the steps of adding to the dispersion a material having a boiling point higher than temperature (T), which is the boiling point of the solvent. In one embodiment, the solvent comprises or consists of ethylene glycol or oligomers of ethylene glycol having 2 to 5 repeat units. In such embodiments, temperature T may be at least 180°C, or 190°C, or 195°C, or even at least 200°C. Materials which have a boiling point higher than temperature T may include other solvents but may also include reactive monomeric components. In a particular embodiment, the materials having a boiling point higher than temperature (T) include monomers formed by the reaction product of a lower-aliphatic glycol with dimethyl terephthalate or the reaction product of a lower-aliphatic diol with terephthalic acid. The materials having a boiling point higher than temperature (T) may also include bis(2-hydroxyethyl)terephthalate, 2- hydroxyethyl terephthalic acid, or mixtures thereof.

[0067] After mixing or while mixing the material having a boiling temperature higher than (T) with the dispersion described herein the mixture is heated to a temperature that is at least T or higher. In some embodiments, the mixture is heated to temperatures above 180°C, or 190°C, or 195°C, or 200°C, or even at least 250°C, for example, 200°C to 300°C, or even 250°C to 295°C. The dispersant of the present invention unexpectedly provides a stable pigment dispersion at elevated temperatures.

[0068] In one embodiment, the present invention also provides a method for producing a pigmented polymer comprising the steps of providing a pigment dispersion comprising, (i) a solvent, comprising or consisting of ethylene glycol; (ii) a dispersant comprising a salt of P and X; wherein P is a polyether functionalized polyacid formed via the reaction of (i) a polyacid Z, (ii) polyether mono-nucleophile C, and, optionally, (iii) a non-polymeric mono-nucleophile D, and X is an alkali metal, an alkaline earth metal, ammonia, an amine or mixtures thereof. Each of the components and the preparation of the dispersant are as described hereinabove. The present invention also includes the use of a pigment dispersion in the manufacture of a polymer, for example, polyethylene terephthalate, wherein the pigment dispersion contains the dispersant as described herein.

[0069] In one embodiment, the pigmented polymer prepared by the method of the present invention is polyethylene terephthalate (PET). Preparation processes for PET are known to those skilled in the art and are described in references such as US Publication No. 2003/0105214 which is incorporated by reference herein. In the process, monomers for preparation of PET polymer are formed by transesterification or esterification reactions. The monomers are prepared by the transesterification or esterification reaction of dimethyl terephthalate and a lower-aliphatic diol (such as ethylene glycol or mono-ethylene glycol) or terephthalic acid and a lower aliphatic diol (such as ethylene glycol or mono-ethylene glycol). The products of the transesterification or esterification reactions include bis-(2-hydroxy ethyl) terephthalate or 2-hy- droxyethyl terephthalic acid. In one embodiment of the invention, the dispersion described herein and the product of the transesterification or esterification reaction are mixed and then heated to temperatures of at least 180°C, or at least 190°C, or at least 195°C, or at least 200°C, or even at least 250°C, for example, 200°C to 300°C, or even 250°C to 295°C. [0070] In one embodiment, the polymer produced by the method of the present invention comprises from 0.01 to 20% based on the weight of the polymer, further for example 0.1 to 2% by weight, or even 0.4% to 1.6% by weight of the pigment. In one exemplary embodiment, the pigment comprises carbon black.

[0071] The following examples provide illustrations of the invention. These examples are non-exhaustive and are not intended to limit the scope of the invention.

EXAMPLES

[00183] A series of polymer intermediates (Z) are prepared as follows:

[00184] Intermediate 1: Aqueous polyacrylic acid (49.5% active) (Carbos- perse™ K-732) (500.00 parts) and polyether amine (Surfonamine® L-207) (920.81 parts) are heated at 120 °C and water removed for 7.5 hours, yielding a clear light yellow viscous liquid. Acid value = 128.23 mgKOH g' ¹ , Amine Value = 21.72 mgKOH g' ¹ , Active content = 97.5%.

[00185] Intermediate 2: Aqueous polyacrylic acid (49.5% active) (Carbos- perse™ K-732) (250.00 parts) and polyether amine (Surfonamine® L-207) (460.41 parts) are heated at 120 °C and water removed for 12.5 hours, yielding a clear colourless viscous liquid. Acid value = 122.68 mgKOH g' ¹ , Amine Value = 10.75 mgKOH g' ¹ , Active content = 98.6%.

[00186] Intermediate 3: Aqueous polyacrylic acid (49.5% active) (Carbos- perse™ K-732) (50.00 parts) and polyether amine (Surfonamine® L-207) (92.08 parts) are heated at 150 °C and water removed for 24.0 hours, yielding a clear light yellow viscous liquid. Acid value = 105.55 mgKOH g' ¹ , Amine Value = 4.37 mgKOH g' ¹ , Active content = 99.7%.

[00187] Intermediate 4: Aqueous polyacrylic acid (49.5% active) (Carbos- perse™ K-732) (50.00 parts) and polyether amine (Surfonamine® L-100) (46.04 parts) are heated at 120 °C and water removed over 7.5 hours, yielding a clear amber viscous gel. Acid value = 201.33 mgKOH g' ¹ , Amine Value = 16.10 mgKOH g' ¹ , Active content = 99.7%.

[00188] Intermediate 5: Aqueous polyacrylic acid (49.5% active) (Carbos- perse™ K-732) (240.00 parts) and polyether amine (Surfonamine® L-207) (441.99 parts) are heated at 120 °C and water removed over 7.3 hours. Resulting material is heated to 140°C and phenethylamine (53.56 parts) is added over 30-45 minutes. Resulting material is heated at 150 °C and water removed over 6.75 hours, yielding a clear yellow viscous liquid. Acid value = 45.22 mgKOH g-1, Amine Value = 7.76 mgKOH g' ¹ , Active content = 99.2%.

[00189] Intermediate 6: Aqueous polyacrylic acid (49.5% active) (Carbos- perse™ K-732) (50.00 parts) and polyethylene glycol monomethyl ether MW 750 (85.64 parts) are heated at 160 °C and water removed over 24.0 hours, yielding an opaque yellowish grey solid. Acid value = 62.61 mgKOH g' ¹ , Active content = 100.0%.

[00190] Intermediate 7: Aqueous polyacrylic acid (49.5% active) (Carbos- perse™ K-732) (50.00 parts) and polyethylene glycol monomethyl ether MW 2000 (92.08 parts) are heated at 160 °C and water removed over 24.0 hours, yielding a hard, opaque cream solid. Acid value = 89.98 mgKOH g' ¹ , Active content = 100.0%. [00191] Intermediate 8: Aqueous polyacrylic acid (49.5% active) (Carbos- perse™ K-732) (250.00 parts) and polyethylene glycol monomethyl ether MW 1000 (230.20 parts are heated at 160 °C and water removed over 24.0 hours, yielding a clear amber viscous liquid. Acid value = 152.63 mgKOH g' ¹ , Active content = 99.8%. [00192] Intermediate 9: Aqueous polyacrylic acid (49.5% active) (Carbos- perse K-732) (75.00 parts) and polyether amine (Surfonamine L-300) (182.47 parts) are heated at 120 °C and water removed for 21 hours, yielding a clear brown solid. Acid value = 89.34 mgKOH ^-1 -, Amine Value = 3.31 mgKOH g' ¹ , Active content = 100.00%.

[00193] Intermediate 10: Aqueous polyacrylic acid (49.5% active) (Carbos- perse K-732) (53.48 parts) and polyether amine (Surfonamine L-300) (98.53 parts) are heated at 120 °C and water removed for 13 hours, yielding an opaque yellow solid. Acid value = 121.14 mgKOH g-1, Amine Value = 4.73 mgKOH g' ¹ , Active content = 100.00%.

[00194] Intermediate 11: Aqueous polyacrylic acid (49.5% active) (Carbos- perse K-732) (150.00 parts) and polyether amine (Surfonamine L-207) (212.71 parts) are heated at 120 °C and water removed for 19 hours, yielding a clear dark amber viscous liquid. Acid value = 151.60 mgKOH g-1, Amine Value = 11.61 mgKOH g' ¹ , Active content = 99.49%. [00195] A series of dispersant examples were prepared or provided as described below. The pH of the dispersant was measured using a 50% solution of the dispersant in ethylene glycol:

[00196] Example 1: Intermediate 5 (30.00 parts) and deionized water (20.00 parts) are heated at 50 °C for 1 hour then cooled. 2-dimethylamino-2-methylpropanol (80% in water) (2.33 parts) is added to the resultant material and stirred for 2 hours, yielding a clear yellow solution. Active content = 58.6%, pH = 7.

[00197] Example 2: Intermediate 5 (60.00 parts) and deionized water (40.00 parts) are heated at 50 °C for 1 hour then cooled. 2-dimethylamino-2-methylpropanol (80% in water) (2.33 parts) is added to the resultant material and stirred for 2 hours, yielding a clear yellow solution. Active content = 58.2%, pH = 9.

[00198] Example 3: Example 2 (50.00 parts) and hydrochloric acid solution (0.5 M in water) (7.03 parts) are stirred for 2 hours, yielding a clear yellow solution. Active content = 52.61, pH = 7.

[00199] Example 4: Intermediate 1 (220.00 parts) and deionized water (220.00 parts) are heated at 50 °C for 1 hour. 2-dimethylamino-2-methylpropanol (80% in water) (72.84 parts) and deionised water (43.70 parts) are added to the resultant material and heated for 1.5 hours, yielding a clear colourless solution. Active content = 50.0%, pH = 10.

[00200] Example 5: Intermediate 1 (25.00 parts) and ethylene glycol (50.00 parts) are heated at 60 °C for 1 hour. Polyethylene imine MW 1800 (Epomin™ SP- 018) (2.50 parts) is added to the resultant material and heated for 1.5 hours, yielding a clear light yellow solution. Active content = 39.2%, pH = 8.

[00201] Example 6: Intermediate 1 (25.00 parts) and ethylene glycol (50.00 g) are heated at 60 °C for 1 hour. Polyethylene imine MW1800 (Epomin™ SP-018) (3.75 parts) is added to the resultant material and heated for 2 hours, yielding a clear yellow viscous solution. Active content = 35.6%, pH = 9.

[00202] Example 7: Intermediate 1 (25.00 parts) and ethylene glycol (50.00 parts) are heated at 60 °C for 1 hour. Polyethylene imine MW 1800 (Epomin™ SP- 018) (5.00 parts) is added to the resultant material and heated for 2 hours, yielding a clear yellow viscous solution. Active content = 37.0%, pH = 10. [00203] Example 8: Intermediate 2 (230.00 parts) and ethylene glycol (253.00 parts) are heated at 60 °C for 1 hour. Polyethylene imine MW1800 (Epomin™ SP-018) (23.00 parts) is added to the resultant material and heated for 1 hour, yielding a clear yellow viscous solution. Active content = 49.0%, pH = 7.

[00204] Example 9: Intermediate 1 (25.00 parts) and ethylene glycol (50.00 parts) are heated at 60 °C for 1 hour. Polyethylene imine MW600 (Epomin™ SP- 006) (2.50 parts) is added to the resultant material and heated for 1 hour, yielding a clear yellow solution. Active content = 35.5%, pH = 7.

[00205] Example 10: Intermediate 3 (25.00 parts) and ethylene glycol (27.50 parts) are heated at 60 °C for 1 hour. Polyethylene imine MW 1800 (Epomin™ SP- 018) (2.50 parts) is added to the resultant material and heated for 3 hours, yielding a clear yellow gelled solution. Active content = 49.2%, pH = 6.

[00206] Example 11: Intermediate 4 (25.72 parts) and ethylene glycol (28.29 parts) are heated at 60 °C for 1 hour. Polyethylene imine MW 1800 (Epomin™ SP- 018) (2.57 parts) is added to the resultant material and heated for 3 hours, yielding a clear yellow gelled solution. Active content = 48.3%, pH = 6.

[00207] Example 12: Intermediate 5 (35.00 parts) and ethylene glycol (38.50 parts) are heated at 60 °C for 1 hour. Polyethylene imine MW 1800 (Epomin™ SP- 018) (3.50 parts) is added to the resultant material and heated for 1 hour, yielding a clear yellow solution. Active content = 49.9%, pH = 8.

[00208] Example 13: Intermediate 6 (25.00 parts) and ethylene glycol (27.50 parts) are heated at 60 °C for 1 hour. Polyethylene imine MW 1800 (Epomin™ SP- 018) (2.50 parts) is added to the resultant material and heated for 1 hour, yielding a clear yellow gelled solution. Active content = 49.4%, pH = 7.

[00209] Example 14: Intermediate 7 (194.00 parts) and ethylene glycol (320.10 parts) are heated at 60 °C for 1 hour. Polyethylene imine MW1800 (Epomin™ SP-018) (19.40 parts) is added to the resultant material and heated for 2.25 hours, yielding a clear amber solution. Active content = 39.6%, pH = 6.

[00210] Example 15: Intermediate 9 (158.36 parts) and ethylene glycol (348.39 parts) are heated at 60 °C for 0.25 hours. Polyethylene imine MW 1800 (Epomin SP- 018) (15.84 parts) is added to the resultant material and heated for 1 hour, yielding a clear yellow solution. Active content = 33.7%, pH = 6. [00211] Example 16: Intermediate 10 (83.32 parts) and ethylene glycol (91.65 parts) are heated at 60 °C for 0.25 hours. Polyethylene imine MW 1800 (Epomin SP- 018) (8.33 parts) is added to the resultant material and heated for 0.75 hours. Ethylene glycol (158.13 parts) is added to the resulting material and heated for 5.75 hours, yielding a clear yellow solution. Active content = 26.6%, pH = 6.

[00212] Example 17: Intermediate 11 (201.35 parts) and ethylene glycol (221.49 parts) are heated at 60 °C for 0.25 hours. Polyethylene imine MW1800 (Epomin SP-018) (20.14 parts) is added to the resultant material and heated for 2.33 hours. Ethylene glycol (157.70 parts) is added to the resulting material and heated for 4.5 hours, yielding a clear amber solution. Active content = 36.1%, pH = 6.

[00213] Comparative example 1: Intermediate 1

[00214] Comparative example 2: Example 7 of patent WO2012125609A1

[00215] Comparative example 3: Morwet D-809 (Nouryon) Naphthalene sulfonic acid-formaldehyde condensate

[00216] Comparative example 4: Orotan SN (Dow) - Naphthalene sulfonic acid-formaldehyde condensate

[00217] Test 1 - High temperature test 200°C: 1.05 g of the example or comparative example (of 100% active material not including ethylene glycol or water i.e. 2.10 g of a 50% active material would be used) to be tested and 7.45 g of ethylene glycol (this value is reduced by the amount of non-active material added as part of the example or comparative example i.e. for a 50% active material 6.40 g) were charged to 32 mL vial and shaken until the sample fully dissolves. Glass beads (17.00 g) and carbon black (Special Black 4, 1.50 g) were charged to the vial and the vial sealed. The material was then milled for 16 hours on a horizontal shaker to produce a mill base. The mill base (1.00 g) was then removed from the vial and charged to a 32 mL vial. Ethylene glycol (6.75 g) was charged to the vial and the contentswere then stirred until homogeneous to produce a dilute mill base. The vial was heated to 200 °C. Once the dilute mill base had reached 200 °C it was examined to determine if it was homogeneous or not. With non-homogeneous materials having a much greater proportion of pigment at the bottom of the vial and with homogeneous being a pass. The results are summarized in Table 1.

[00218] Table 1

[00219] Test 2: Addition of Material Having a Boiling Point Higher than Ethylene Glycol solvent (Bis-(2-hydroxyethyl) terephthalate (“BHET”)) at 200 °C: The material resulting from Test 1 was carried forward into Test 2. BHET (7.75 g) was charged to the vial at 200 °C. Once the BHET had melted the sample was stirred and heated for a further hour. This process was repeated a further two times, so that in total 23.25 g of BHET had been added in total and the sample had been heated for a total of 3 hours. The sample is allowed to cool to room temperature. Once the sample had cooled it was examined firstly to determine homogeneity, with a non-homogeneous sample having either/both black specs throughout or a black layer at the bottom. Secondly, to determine the colour. With a pass being a homogeneous sample that was black in colour. The results are summarized in Table 2.

[00220] Table 2

[00221] This test indicates that the pigment dispersion described herein is able to be used at elevated temperatures, for example, the temperature required to polymerize a PET polymer.

[00222] Each of the documents referred to above is incorporated herein by reference, including any prior applications, whether or not specifically listed above, from which priority is claimed. The mention of any document is not an admission that such document qualifies as prior art or constitutes the general knowledge of the skilled person in any jurisdiction. Except in the Examples, or where otherwise explicitly indicated, all numerical quantities in this description specifying amounts of materials, reaction conditions, molecular weights, number of carbon atoms, and the like, are to be understood as modified by the word "about." It is to be understood that the upper and lower amount, range, and ratio limits set forth herein may be independently combined. Similarly, the ranges and amounts for each element of the invention can be used together with ranges or amounts for any of the other elements. [00223] As used herein, the transitional term “comprising,” which is synonymous with “including,” “containing,” or “characterized by,” is inclusive or open- ended and does not exclude additional, un-recited elements or method steps. However, in each recitation of “comprising” herein, it is intended that the term also encompass, as alternative narrower embodiments, the phrases “consisting essentially of’ and “consisting of,” where “consisting of’ excludes any element or step not specified and “consisting essentially of’ permits the inclusion of additional un-reci ted elements or steps that do not materially affect the basic and novel characteristics of the composition or method under consideration.

[00224] While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. In this regard, the scope of the invention is to be limited only by the following claims.