Bio-renewable energy-curable inkjet inks

Abstract

An energy-curable inkjet ink comprises 30-80 wt.% monofunctional (meth)acrylate monomers, 5-35 wt.% N-vinyl monomer, 10-60 wt.% isobornyl acrylate, 1-25 wt.% monofunctional, linear or branched C6-C18

Description

As part of the pursuit for increased sustainability and reduced carbon footprint, raw materials with a bio-renewable content (BRC) are now available to the ink formulator. Reference has been made to formulations which, although possessing a significant BRC content, are lacking in some performance aspects required for commercial end use applications. The present invention details an approach which can deliver high bio-renewable content whilst maintaining performance properties (e.g. cure speed, adhesion and flexibility) required for industrial end use applications. While maintaining high levels of BRC, one particular material that the present invention aims to minimize or eliminate is decanediol diacrylate (DDDA) to provide formulations with good flexibility, cure and adhesion to typical graphics substrates. As is shown in the examples section, anything more than a small amount (0.1 to about 8%) of DDDA has a detrimental effect on adhesion. A further aspect of the invention is the use of iso-octyl acrylate (IOA) and lauryl acrylate (LA) derived from biorenewable raw materials. These monomers have been found to provide useful adhesion properties to energy-curable inkjet ink compositions over a range of substrates. Background Documents: GUANGZHOU MEIJING COMPUTER GRAPHIC TECH CO LTD CN108530990 (B): A preparation method of bio-based modified UV curable inkjet ink, characterized in that it first synthesizes the acrylated product of vegetable oil-based tricarboxylic acid and acrylated gallic acid, and then blends with basic film-forming resin to prepare bio-based modified ink. Permanent UV curable inkjet ink. Based on different materials than the present application. INST CHEMICAL IND FOREST PRODUCTS CAF CN113461847 (B): Photocurable resin based on epoxy vegetable oil and gallic acid as well as a preparation method and application. The preparation method comprises reacting gallic acid with an acrylic anhydride to obtain a gallic acid triacrylate / acrylic acid compound; then carrying out epoxy ring-opening reaction to obtain a biobased epoxy acrylate prepolymer; and finally, adding a diluting monomer, a photoinitiator, a polymerization inhibitor and the like. The resin can be used in photocuring 3D printing materials, coatings, printing ink and the like. Based on different materials than the present application. SIEGWERK DRUCKFARBEN AG &CO KGAA [DE] PL2620480 (T3): Printing ink, in particular a gravure printing ink or a flexographic printing ink, comprising a nitrated lignin as at least one binder component. Based on different materials than the present application. SAKATA INX CORP US2023257608A1: An active energy ray-curable inkjet printing ink composition according to (A) thru (E) below, where the total content of (D) and (E) accounts for 30.0 to 60.0% by mass. (A) an acrylated amine compound having two photopolymerizable functional groups and two amino groups at 1.0-20.0% by mass; (B) alkoxy group-containing (meth)acrylate monomers at 2.0-20.0% by mass; (C) a (meth)acrylate monomer containing an alkyl group with 10-20 carbon atoms at 2.0 to 25.0% by mass; (D) at least one material selected from 1,6-hexanediol diacrylate, 3-methyl-l,5-pentanediol diacrylate, dipropylene glycol diacrylate, propoxylated(2)neopentyl glycol diacrylate, and hydroxypivalic acid neopentyl glycol diacrylate at 5.0-25.0% by mass; and (E) a plant oil-derived 1,10-decanediol diacrylate is contained at 10.0-40.0% by mass. Requires the use of DDDA between 10-40% and alkoxy acrylate between 2-20% which gives very limited adhesion and flexibility. No mention of iso-octyl diacrylate. Citation or identification of any document in this application is not an admission that such represents prior art to the present invention. DETAILED DESCRIPTION Definitions Single pass inkjet printing = a printing process where the inkjet printheads are fixed and the substrate passes underneath the printheads either as a reel or is sheetfed. A single pass inkjet press capable of a multi-UV exposure process may comprise two or more UV light sources positioned after the printing stations in order to provide the multiple irradiations required by the method of the invention in a single pass of the inkjet head. Multipass inkjet printing = the printheads passes over the substrate multiple times to build up the print image. A single UV light source could be used with multipass inkjet printing to provide multiple irradiations. (Methjacrylate refers to both acrylates and methacrylates. Unless otherwise stated, all percentages are weight percent (wt%). References to the wt% of a component, e.g., 0 to 25wt% of one or more linear or branched Ce-Cis alkyl acrylates, define the total amount of all components that satisfy the component definition that are included in the composition. High BRC content - comprises at least 50% biorenewable content. Monofunctional acrylate - an acrylate comprising a single polymerisable group, wherein the polymerisable group is polymerisable via radical polymerisation (e.g., an acrylate or vinyl group). Non-alkoxylated - compounds that do not comprise repeated ethyleneoxide and / or propylene oxide monomeric units as chain extenders. The present application is drawn to energy curable inkjet inks having a bio-renewable carbon content >30%, containing the following materials: 30-80 wt%, preferably 40-70 wt% monofunctional (meth)acrylate monomers; 5-35 wt%, preferably 10-30 wt% N-vinyl monomer; 10-60% wt%, preferably 30-60 wt% plant-derived isobornyl acrylate; 0-25 wt%, preferably 5-20wt% iso-octyl acrylate (ISOA); 0-25 wt%, preferably 5-20wt% lauryl acrylate; and 0-25 wt%, preferably 1-10 wt% acrylated amine. Ultraviolet light (UV) reactive inkjet printing has become well known as a reliable printing method for graphic display and single pass applications such as printing onto labels. Within the market area of graphics printing, multi-pass energy curing inkjet can be used where short runs are required, or there are advantages in eliminating time taken for image change over; or to avoid the need to hold printed stock (‘Point of fill’ printing). After printing, there is a cure stage where photoinitiators (Pi’s) interact with UV light to form free-radicals which then react with double bonds in the acrylate monomers to initiate free radical polymerization, creating a cured, colored image. The photoinitiators may be eliminated, and the inks would be cured by electron beam to alleviate some of the issues related to migration, taint and odour associated with unreacted photoinitiator. Monomers play a major role in determining the physical properties of a radiation curable inkjet formulation and the resulting cured ink film. Regardless of their chemical structure, they always require at least one polymerizable group. In the case of curing by a free-radical polymerization mechanism, which can be initiated by electron beam ionization radiation or via radical-generating photoinitiators, the polymerizable groups are in general carbon-carbon double bonds. The most important radically curable monomers used in inks contain acrylate or, less frequently, methacrylate groups. The monomers are usually derived from monoalcohols, diols, or polyols that are sometimes alkoxylated which are usually esterified with either acrylic or methacrylic acid. The functionality, i.e., the number of polymerizable groups per molecule, is of major importance to the final performance of the ink. Formulations containing monomers with one polymerizable group will produce a linear polymer structure, while those with two or more polymerizable groups will give rise to crosslinked polymer structures. As the crosslink density increases, so will the hardness, chemical and scratch resistance but a resultant loss of adhesion often occurs. The crosslink density depends upon the average number of polymerizable groups per molecule of the monomer (i.e., the functionality) and the molecular weight between two crosslinks. The functionality normally lies between one and six for acrylate monomers with either one or two polymerizable groups being preferred for the formulation of free radically cured inkjet inks. Examples of suitable monofunctional ethylenically unsaturated monomers include but are not limited to the following (and combinations thereof), where the terms ethoxylated refers to chain extended compounds through the use of ethyleneoxide, propoxylated refers to chain extended compounds through the use of propylene oxide, and alkoxylated refers to chain extended compounds using either or both ethyleneoxide and propylene oxide. Equivalent methacrylate compounds are also capable of being used, although those skilled in the art will appreciate that methacrylate compounds have lower reactivity than their equivalent acrylate counterparts: isobutyl acrylate; cyclohexyl acrylate;; n-octyl acrylate; iso-nonyl acrylate; octyl / decyl acrylate; 2- propyl heptyl acrylate; tridecyl acrylate; hexadecyl acylate; stearyl acrylate; iso-stearyl acrylate; behenyl acrylate; tetrahydrofurfuryl acrylate; 4-t.butyl cyclohexyl acrylate; 3,3,5-trimethylcyclohexane acrylate; isobornyl acrylate; dicyclopentyl acrylate; dihydrodicyclopentadienyl acrylate; dicyclopentenyloxyethyl acrylate; dicyclopentanyl acrylate; benzyl acrylate; phenoxy ethyl acrylate; 2-hydroxy-3-phenoxypropyl acrylate; alkoxy lated nonylphenol acrylate; cumyl phenoxyethyl acrylate; cyclic trimethylolpropane formal acrylate; 2(2-ethoxyethoxy) ethyl acrylate; polyethylene glycol monoacrylate; polypropylene glycol monoacrylate; caprolactone acrylate; ethoxylated methoxy polyethylene glycol acrylate; methoxy triethylene glycol acrylate; tripropyleneglycol monomethyl ether acrylate; diethylenglycol butyl ether acrylate; alkoxylated tetrahydrofurfuryl acrylate; ethoxylated ethyl hexyl acrylate; alkoxylated phenol acrylate; ethoxylated phenol acrylate; ethoxylated nonyl phenol acrylate; propoxylated nonyl phenol acylate; polyethylene glycol o-phenyl phenyl ether acrylate; ethoxylated p-cumyl phenol acrylate; ethoxylated nonyl phenol acrylate; alkoxylated lauryl acrylate; ethoxylated tristyrylphenol acrylate; N-(acryloyloxyethyl)hexahydrophthalimide; N-butyl 1,2 (acryloyloxy) ethyl carbamate; acryloyl oxyethyl hydrogen succinate; octoxypolyethylene glycol acrylate; octafluoropentyl acrylate; 2-isocyanato ethyl acrylate; acetoacetoxy ethyl acrylate; 2-methoxyethyl acrylate; dimethyl aminoethyl acrylate; 2-carboxyethyl acrylate; 4-hydroxy butyl acrylate. Increasing the BRC content of ink compositions is desirable, for the reasons discussed herein. However, due to a lack of commercial availability of many common ink components with high BRC, increasing the BRC of inks is not trivial. Accordingly, it may be necessary to replace components with different components having high BRC. However, non-like-for-like replacement of components can result in unforeseen variations in ink properties. As discussed herein, the inventors have identified a composition comprising a particular combination of monomers, which can be obtained with high BRC, that desirable properties to the inks (e.g., adhesion and retaining substrate flexibility). As will be shown m the Examples section, three particularly useful monomers for the present application are isobornyl acrylate (IBOA), iso-octyl acrylate (ISOA) and lauryl acrylate (LA) due to their BRC content and ability to impart good performance properties, such as adhesion, cure and flexibility. Other monofunctional, linear or branched Ce-Cis alkyl acrylates, such as stearyl acrylate, may also be used with the invention. Examples of suitable multifunctional ethylenically unsaturated monomers include but are not limited to the following (and combinations thereof), where the terms ethoxylated refers to chain extended compounds through the use of ethyleneoxide, propoxylated refers to chain extended compounds through the use of propylene oxide, and alkoxylated refers to chain extended compounds using either or both ethyleneoxide and propylene oxide. Equivalent methacrylate compounds are also capable of being used, although those skilled in the art will appreciate that methacrylate compounds have lower reactivity than their equivalent acrylate counterparts: 1,3-butylene glycol diacrylate; 1,4-butanediol diacrylate; neopentyl glycol diacrylate; ethoxylated neopentyl glycol diacrylate; propoxylated neopentyl glycol diacrylate; 2-methyl-l,3-propanediyl ethoxy acrylate; 2-methy 1-1,3-propanediol diacrylate; ethoxylated 2-methyl-l,3-propanediol diacrylate; 3 methyl 1,5- pentanediol diacrylate; 2-butyl-2-ethy 1-1,3-propanediol diacrylate; 1,6-hexanediol diacrylate; alkoxylated hexanediol diacrylate; ethoxylated hexanediol diacrylate; propoxylated hexanediol diacrylate; 1,9-nonanediol diacrylate; 1,10 decanediol diacrylate; ethoxylated hexanediol diacrylate; alkoxylated hexanediol diacrylate; diethyleneglycol diacrylate; triethylene glycol diacrylate; tetraethylene glycol diacrylate; polyethylene glycol diacrylate; propoxylated ethylene glycol diacrylate; dipropylene glycol diacrylate; ripropyleneglycol diacrylate; polypropylene glycol diacrylate; poly (tetramethylene glycol) diacrylate; cyclohexane dimethanol diacrylate; ethoxylated cyclohexane dimethanol diacrylate; alkoxylated cyclohexane dimethanol diacrylate; polybutadiene diacrylate; hydroxypivalyl hydroxypivalate diacrylate; tricyclodecanedimethanol diacrylate; l,4-butanediylbis[oxy(2- hydroxy-3,1-propanediyl)]diacrylate; ethoxylated bisphenol A diacrylate; propoxylated bisphenol A diacrylate; propoxylated ethoxylated bisphenol A diacrylate; ethoxylated bisphenol F diacrylate; 2-(2-Vinyloxyethoxy)ethyl acrylate; dioxane glycol diacrylate; ethoxylated glycerol triacrylate; glycerol propoxylate triacrylate; pentaerythritol triacrylate; tnmethylolpropane tnacrylate; caprolactone modified trimethylol propane triacrylate; ethoxylated trimethylolpropane triacrylate; propoxylated trimethylol propane triacrylate; tris (2-hydroxy ethyl) isocyanurate triacrylate; e-caprolactone modified tris (2-hydroxy ethyl) isocyanurate triacrylate; melamine acrylate oligomer; pentaerythritol tetraacrylate; ethoxylated pentaerythritol tetraacrylate; di-trimethylolpropane tetra acrylate; dipentaerythritol pentaaacrylate; dipentaerythritol hexaacrylate; ethoxylated dipentaerythritol hexaacrylate. The inventors have found that the presence of non-alkoxylated (e.g., ethoxylated and / or propoxylated) monomers of high functionality can have a detrimental effect on the properties of the inks. Therefore, the compositions may comprise reduced amounts of non-alkoxylated monomers having a functionality of 6 or greater. However, the inventors found that alkoxylated (i.e., ethoxylated and / or propoxylated) monomers of high functionality can be included, preferably in amounts up to 10wt%, up to 5wt% or more preferably up to 3wt%, without compromising ink properties. As mentioned previously, inventors have found that using decanediol diacrylate (DDDA) at concentrations much m excess of 5% (w / w) m the inventive UV-curable inkjet compositions can have a detrimental effect on the adhesion and flexibility of the cured prints. This is demonstrated by way of the examples. Alkoxylated glycerol and other alcohols, especially ethoxylated polyols, for example polyethylene glycol and polypropylene glycol, could serve as sources for high BRC acylated materials for use in the compositions of the present application. A further class of high BRC materials that could be used in the compositions of the present are acrylated rosin maleic esters. Other functional monomer classes capable of being used in part in these formulations include cyclic lactam such as N-vinyl Caprolactam; N-vinyl oxazolidinone and N-vinyl pyrrolidone, and secondary or tertiary acrylamides such as acryloyl morpholine; diacetone acrylamide; N-methyl acrylamide; N-ethyl acrylamide; N-isopropyl acrylamide; N-t.butyl acrylamide; N-hexyl acrylamide; N-cyclohexyl acrylamide; N-octyl acrylamide; N- t.octyl acrylamide; N-dodecyl acrylamide; N-benzyl acrylamide; N-(hydroxymethyl)acrylamide; N-isobutoxymethyl acrylamide; N- butoxymethyl acrylamide; N,N-dimethyl acrylamide; N,N-diethyl acrylamide; N,N-propyl acrylamide; N,N-dibutyl acrylamide; N,N-dihexyl acrylamide; N,N-dimethylamino methyl acrylamide; N,N-dimethylamino ethyl acrylamide; N,N-dimethylamino propyl acrylamide; N,N-dimethylamino hexyl acrylamide; N,N-diethylamino methyl acrylamide; N,N-diethylamino ethyl acrylamide; N,N-diethylamino propyl acrylamide; N,N-dimethylamino hexyl acrylamide; and N,N’-methylenebisacrylamide. It should be understood that, although the invention is directed towards energy-curable inkjet ink compositions comprising for example, IO A, LA and IBOA derived from BRC raw materials, other monomers derived from BRC raw materials may also be used in inkjet compositions described in the present invention. Photoinitiators include, but are not limited to, the following: a-hydroxyketones such as; 1-hydroxy-cyclohexyl-phenyl-ketone; 2-hydroxy-2-methyl-1 -phenyl-1 -propanone; 2-hydroxy-2-methyl-4’-tert-butyl-propiophenone; 2-hydroxy-4’-(2-hydroxyethoxy)-2-methyl-propiophenone; 2-hydroxy-4’-(2-hydroxypropoxy)-2-methyl-propiophenone; oligo 2-hydroxy-2-methyl-1 -[4-( 1 -methyl-vinyljphenyl] propanone; bL[4-(2-hydroxy-2-methylpropionyl)phenyl]methane; 2-Hydroxy-1-[1 -[4-(2-hydroxy-2-methylpropanoyl )phenyl]-l ,3.3-inmethy lindan-5-yl]-2-methylpropan-1 -one and 2-Hydroxy-l-[4-[4-(2-hydroxy-2-methylpropanoyl)phenoxy]phenyl]-2-methylpropan-l-one; acylphosphine oxides such as; 2,4,6-trimethylbenzoyl-diphenylphosphine oxide; ethyl (2,4,6-trimethylbenzoyl)phenyl phosphinate; and bis-(2,4,6-trimethylbenzoyl)-phenylphosphine oxide; a-aminoketones such as; 2-methyl-l-[4-methylthio)phenyl]-2-morpholinopropan-l-one; 2-benzyl-2-dimethylamino-l-(4-morpholinophenyl)-butan -l-one; and 2-dimethylamino-2-(4-methy 1-benzyl)-1 -(4-morpholin-4-yl-phenyl)-butan-1 -one; thioxanthones such as; 2-4-diethylthioxanthone, isopropylthioxanthone, 2-chlorothioxanthone, and l-chloro-4-propoxythioxanthone; benzophenones such as; such as benzophenone, 4-phenylbenzophenone, and 4-methyIbenzophenone; methyl-2-benzoyIbenzoate; 4-benzoyl-4-methyldiphenyl sulphide; 4- hydroxybenzophenone; 2,4,6-trimethyl benzophenone, 4,4-bis(diethylamino)benzophenone; benzophenone-2-carboxy(tetraethoxy)acrylate; 4-hydroxybenzophenone laurate and 1-(-4-[benzoylphenylsulpho]phenyl]-2-methyl-2-(4-methylphenylsulphonyl)propan-l-one; phenylglyoxylates such as; phenyl glyoxylic acid methyl ester; oxy-phenyl-acetic acid 2-[hydroxyl-ethoxy]-ethyl ester, or oxy-phenyl-acetic acid 2-[2-oxo-2-phenyl-acetoxy-ethoxy]-ethyl ester; oxime esters such as; 1-phenyl-l,2-propanedione-2-(O-ethoxycarbonyl)oxime; [1-(4-phenylsulfanylbenzoyl)heptylideneamino]benzoate, or [ 1 -[9-ethyl-6-(2-methylbenzoyl)carbazol-3-yl]-ethylideneamino]acetate; Examples of other suitable photoinitiators include diethoxy acetophenone; benzil; benzil dimethyl ketal; titanocen radical initiators such as titanium-bis(r) 5-2,4-cyclopentadien-l-yl)-bis-[2,6-difluoro-3-(l H-pyrrol-l-yl)phenyl]; 9-fluorenone; camphorquinone; 2-ethyl anthraquinone; and the like. An amine synergist may also be included in the formulation. Suitable examples include, but are not limited to, the following: Aromatic amines such as; 2-(dimethylamino)ethylbenzoate; N-phenyl glycine; benzoic acid, 4-(dimethylamino)-, l,r-[(methylimino)di-2,l-ethanediyl] ester; and simple alkyl esters of 4-(N,N-dimethylamino)benzoic acid, with ethyl, amyl, 2-butoxyethyl and 2-ethylhexyl esters being particularly preferred; other positional isomers of N,N- dimethylarnino)benzoic acid esters are also suitable; aliphatic amines such as N-methyldiethanolamine, triethanolamine and tri- isopropanolamine; Aminoacrylates and amine modified polyether acrylates EBECRYL 80, EBECRYL 81, EBECRYL 83, EBECRYL 85, EBECRYL 880, EBECRYL LEO 10551, EBECRYL LEO 10552, EBECRYL LEO 10553, EBECRYL 7100, EBECRYL Pl 15 and EBECRYL Pl 16 available from ALLNEX; CN501, CN550, CN UVA421, CN3705, CN3715, CN3755, CN381 and CN386, all available from Sartomer; GENOMER 5142, GENOMER 5161, GENOMER 5271 and GENOMER 5275 from RAHN; PHOTOMER 4771, PHOTOMER 4967, PHOTOMER 5006, PHOTOMER 4775, PHOTOMER 5662, PHOTOMER 5850, PHOTOMER 5930, and PHOTOMER 4250 all available from IGM, LAROMER LR8996, LAROMER LR8869, LAROMER LR8889, LAROMER LR8997, LAROMER PO 83F, LAROMER PO 84F, LAROMER PO 94F, LAROMER PO 9067, LAROMER PO 9103, LAROMER PO 9106 and LAROMER PO77F, all available from BASF; AGISYN 701, AGISYN 702, AGISYN 703, NeoRad P-81 and NeoRad P-85 ex DSM-AGI. Polymeric photoinitiators and sensitizers are also suitable, including, for example, polymeric aminobenzoates (GENOPOL AB-1 or AB-2 from RAHN, Omnipol ASA from IGM or Speedcure 7040 from Lambson), polymeric benzophenone derivatives (GENOPOL BP-1 or BP-2 from RAHN, Omnipol BP, Omnipol BP2702 or Omnipol 682 from IGM or Speedcure 7005 from Lambson), polymeric thioxanthone derivatives (GENOPOL TX-1 or TX-2 from RAHN, Omnipol TX from IGM, JRCure 1508 from Jiuri or Speedcure 7010 from Arkema), polymeric aminoalkylphenones such as Omnipol 910 from IGM; polymeric benzoyl formate esters such as Omnipol 2712 from IGM; and the polymeric sensitizer Omnipol SZ from IGM. The addition of inert (non-reactive) resins can also be advantageous as these can be used to influence the adhesion of the coating. Typically acrylic based inert resins are preferred. Especially preferred would be inert resins with high BRC content. A stabilizer may also be used in the composition to ensure good pot life of the ink, examples of which are nitroxy based stabilizers such as OHTEMPO, TEMPO, and Irgastab UV10. Phenolic stabilizers such as hydroquinone (HQ), methyletherhydroquinone (MEHQ), butylhydroxytoluene (BHT) and 2,6-di-tert-butyl-N,N-dimethylamino-p-cresol. Nitrosophenylhydroxylamine(NPHA) base inhibitors NPHA, amine salts, and metal salts (Al salt, N-PAL) plus the aromatic amine inhibitors diphenylamine(DPA) and phenylenediamine(PPD). Other suitable stabilizers are florstab UV-1, UV-8, Genorad 16 and 18. A stabilizer based on bioderived materials can be selected to boost the overall BRC content of the formulation. Included in the ink formulation can be a suitable de-aerator, these prevent the formation of air inclusions and pinholes in the cured coating. These also reduce rectified diffusion which can cause reliability issues in the printhead. The following products are available from EVONIK: TEGO AIREX 900, 910, 916, 920, 931, 936, 940, 944, 945, 950, 962, 980, 986. A de-aerator based on bioderived materials can be selected to boost the overall BRC content of the formulation. The compositions of the present application can also include small amounts of solvent to enhance certain properties. When used, solvents would typically be added in an amount not to exceed 5 wt%. BRC solvents are preferred as they would boost the overall BRC content of the formulation. Defoamers can also be included in the formulation, these prevent the formation of foam during manufacture of the ink and also while jetting. These are particularly important with recirculating printheads. Suitable defoamers include TEGO FOAMEX N, FOAMEX 1488, 1495, 3062, 7447, 800, 8030, 805, 8050, 810, 815N, 822, 825, 830,831,835, 840,842, 843, 845, 855, 860, 883, TEGO FOAMEX K3, TEGO FOAMEX K7 / K8 and TEGO TWIN 4000 available from EVONIK. Available from BYK is BYK-066N, 088, 055, 057, 1790, 020, BYK-A 530, 067A, and BYK 354. A defoamer based on bioderived materials can be selected to boost the overall BRC content of the formulation. An example of such a defoamer is one derived from soybean oil. Surface Control Additives are often used to control the surface tension of the ink which is required to adjust the wetting on the face plate of the printhead and also to give the desired drop spread on the substrate or and in the case of multi pass inkjet printing wet on dry drop spread. They can also be used to control the level of slip and scratch resistance of the coating. Suitable surface control additives include but are not limited to TEGO FLOW300, 370,425, TEGO GLIDE 100, 110,130,406, 410,411,415, 420, 432, 435,440, 482, Al 15, B1484, TEGO GLIDE ZG400, TEGO RAD2010, 2011, 2100, 2200N, 2250, 2300, 2500, 2600, 2650, 2700, TEGO TWIN 4000, 4100, TEGO WET 240,250,260,265,270, 280, 500, 505, 510 and TEGO WET KL245 all available from EVONIK. Available from BYK are BYK 333,337, BYK UV3500, BYK UV3535, BYK 378, 347,361, BYK UV3530, 3570, CERAFLOUR 998, 996, NANOBYK 3601, 3610, 3650 and CERMAT 258. From CYTEC EBECRYL 350, 1360, MODAFLOW 9200, EBECRYL 341. From ARKEMA the aliphatic silicone acrylate CN9800 may be used. Surface control additives based on bioderived materials can be selected to boost the overall BRC content of the formulation. Other possible components that can be used to boost the overall BRC content of the compositions of the present application include soybean oil-derived materials, wetting aids derived from alkoxylated natural alcohols, or any other high BRC material. The ink compositions of the present invention may optionally contain one or more colorants, including pigments and / or dyes. Examples of suitable organic or inorganic pigments include carbon black, zinc oxide, titanium dioxide, phthalocyanine, anthraquinones, perylenes, carbazoles, monoazo and disazobenzimidazoles, rhodamines, indigoids, quinacridones, diazopyranthrones, dimtramlines, pyrazoles, diazopyranthrones, dmityamhnes, pyrazoles, diamsidines, pyranthrones, tetracholoroisoindolines, dioxazines, monoazoacrylides and anthrapyrimidines. The dyes include but are not limited to azo dyes, anthraquinone dyes, xanthene dyes, azine dyes, combinations thereof and the like. Commercial organic pigments classified according to Colour Index International according to the following trade designations, blue pigments PB1, PB15, PB15:1, PB15:2, PB15:3, PB15:4, PBI 5:6, PB16, PB60; brown pigments PB5, PB23, and PB265; green pigments PG1, PG7, PG10 and PG36; yellow pigments PY3, PY14, PY16, PY17, PY24, PY65, PY73, PY74, PY83, PY95, PY97, PY108, PY109, PY110, PY113, PY128, PY129, PY138, PY139, PY150, PY151, PY154, PY156, PY175, PY180 and PY213; orange pigments PO5, PO15, PO16, PO31, PO34, PO36, PO43, PO48, PO51, PO60, PO61 and PO71; red pigments PR4, PR5, PR7, PR9, PR22, PR23, PR48, PR48:2, PR49, PR112, PR122, PR123, PR149, PR166, PR168, PR170, PR177, PR179, PR190, PR202, PR206, PR207, PR224 and PR254: violet pigments PV19, PV23, PV32, PV37 and PV42; black pigments. The compositions of the present application may incorporate colorants based on high BRC content to boost the overall BRC content. Examples include algae; biochar; laked carminic acid (cochineal); natural food colors such as alizarin (from madder root), phycocyanin, anthocyanins, beets, beta carotene, curcumin, chlorophyll, etc. A further description and listing of natural colorants can be found in the following article: h ttpa: / / www. scicncedifect.com / science / articte / pii / S26661 54323001357 The pigments are preferably dispersed to less than 1 micrometer with a preferred particle size distribution of 10-500 nm, more preferably 10-350 nm to have better transparency and a wide color gamut. The pigments may be provided in the form of dispersions typically containing 60-90% monomer which can be a mono or multifunctional (meth)acrylate monomer, with added stabilizer, inhibitor, dispersant and optionally a pigment additive / synergist and / or a wetting additive / oligomer / resin. The ratio of pigment to dispersant would usually be between 1:2 to 9:1 depending on the chemistry of the pigment and dispersant. Examples of typical dispersants would include EFKA 7414, 7476, 7477, 7700, 7701, 7702, 7710, 7731, 7732, PX4701 available from BASF and SOLSPERSE 1700, 1900, 24000SC / GR, 26000, 32000, 33000, 35000, 36000, 39000, 41000 and 71000 available from LUBRIZOL. Examples of additive / synergists to aid dispersion stability include SOLSPERSE 5000, 12000 and 22000 from LUBRIZOL. In an energy curable inkjet formulation the solvent resistance will be directly proportional to the crosslink density of the cured coating which will in turn be determined by the functionality of the polymerizable monomers although this will be reduced if the degree of conversion of the monomers is reduced. The degree of conversion could be reduced if the photoinitiator package is not optimized to the spectral output of the lamps or if an inert resin is used in the formulation. The principle will follow that the higher the reactive functionality, the more rapidly crosslink density increases during polymerization. Degree of conversion can also be increased by either elevating the ink temperature during cure, increasing the substate temperature or curing under nitrogen to prevent oxygen inhibition. Steric factors such as the location of the polymerizable groups can also affect degree of conversion. As crosslinking proceeds, the glass transition temperature (Tg) of the cured film will increase with double bond conversion. If the Tg point is lower than the curing temperature, double bond consumption can continue until close to 100% conversion is achieved. The vitrification point and hence the properties of the cured ink can be altered by careful selection of monomers, photoinitiators and stabilizers plus control of external factors such as lamp spectra output, temperature of cure and the presence of nitrogen inerting. Polar groups such as hydroxy or carboxy groups will increase the surface tension, while nonpolar groups such as long alkyl chains, siloxanes, or (fluoro)alkyl groups, reduce it. Good adsorption between the film and the substrate will improve the adhesion. Typically, inclusion of materials with hydroxyl or carboxyl functionality can be beneficial. Selection of monomers that can swell the substrate and increase penetration of the ink into the substrate will help adhesion. Examples of these can include n-vinylcaprolactam and ACMO (acryloyl morpholine) for energy curable inkjet formulations. Another area that causes problems is shrinkage during cure, this will reduce the contact of the cured ink with the substrate which will reduce adhesion. Higher crosslink density will result in greater shrinkage and hence reduced adhesion which can be overcome by curing by electron beam bombardment. The inks of the invention provide a desirable combination of good adhesion and substrate flexibility. The substrates for use in the invention are preferably acrylic and / or vinyl substrates. Bio-renewable raw materials and polymers play a crucial role in promoting sustainability and reducing reliance on fossil fuels. These materials are derived from biomass, such as plants or microorganisms, rather than geologic sources. They can be fully or partially biobased and may also be biodegradable or compostable. Closed-loop recycling of these materials is essential for a sustainable and efficient recycling system. Industry research continues to explore lignocellulose and vegetable oils amongst other materials as sources for bio-acrylate monomers. The invention also covers the use of any monomer that might be derived from raw materials using any portion of recycled material. A possible source of such material, for example, could be from a pyrolysis oil of recycled plastic material. Such materials may not comprise BRC but are sustainable in that they use recycled products. To date it has proven difficult for the inkjet industry to design formulations with a significant biorenewable carbon content, which deliver the range of print properties needed to make them technically viable. In order to discern the level of renewable carbon in a material or product, the AMS (accelerator mass spectrometry) technique may be employed. Biobased testing utilizes carbon-14 measurement via AMS based on standards such as ASTM D6866, ISO 16620, and EN 16640. Materials sourced from biomass contain a known level of the weakly radioactive isotope, carbon-14. At the end of the lifecycle of the plants from which the BRC raw materials are derived they no longer exchange this isotope with the biosphere. Thus, the level of carbon-14 decreases through radioactive decay. Fossil-derived materials that have completed the process of radioactive decay of their carbon-14 content do not have any carbon-14. After pretreatment, samples for radiocarbon dating are prepared for use in an accelerator mass spectrometer by converting them into a solid graphite form. This is done by conversion to carbon dioxide with subsequent graphitization in the presence of a metal catalyst. Burning the samples to convert them into graphite, however, also introduces other elements into the sample like nitrogen 14. When the samples have finally been converted into few milligrams of graphite, they are pressed on to a metal disc. Reference materials are also pressed on metal discs. These metal discs are then mounted on a target wheel so they can be analyzed in sequence. Ions from a caesium gun are then fired at the target wheel, producing negatively ionized carbon atoms. These negatively ionized carbon atoms pass through focusing devices and an injection magnet before reaching the tandem accelerator where they are accelerated to the positive terminal by a voltage difference of two million volts. At this stage, other negatively charged atoms are unstable and cannot reach the detector. The negatively charged carbon atoms, however, move on to the stripper (a gas or a metal foil) where they lose the electrons and emerge as the triple, positively charged carbon atoms. At this stage, molecules that may be present are eliminated because they cannot exist in this triple charged state. The carbon atoms with triple positive charge further accelerate away from the positive terminal and pass through another set of focusing devices where mass analysis occurs. In mass analysis, a magnetic field is applied to these moving charged particles, which causes the particles to deflect from the path they are traveling. If the charged particles have the same velocity but different masses, as in the case of the carbon isotopes, the heavier particles are deflected least. Detectors at different angles of deflection then count the particles. At the end of an AMS run, data is gathered on the number of carbon-12, 13 and 14 atoms in the sample. From this data, a concentration ratio of the isotopes may be calculated to allow evaluation of the level of fractionation. The ratio of carbon-14 to carbon-12 may subsequently be used to quantify the proportion of bio-renewable carbon within the sample. The present invention has been described in detail, including various embodiments thereof. However, it will be appreciated that those skilled in the art, upon consideration of the present disclosure, may make modifications and / or improvements on this invention that fall within the scope and spirit of the invention. EXAMPLES The invention is further described by the following non-limiting examples which further illustrate the invention, and are not intended, nor should they be interpreted to, limit the scope of the 5 invention. Inks were prepared according to Table 1 below and stirred until homogeneous using a silverson mixer. Table 1: Inkjet formulations to compare adhesion and flexibility when cured by 395nm UV LED (E=Inventive; C=Comparative) Material BRC % E-l E-2 E-3 E-4 E-5 E-6 E-7 E-8 E-9 E-10 polyester acrylate 46 ethoxylated TMPTA polyethylene glycol 400 diacrylate lauryl acrylate 80 15.0 hexanediol diacrylate 2-Phen oxyethylacrylate Cyclic Trimethylolpropane Formal Acrylate polyethylene glycol o-phenyl phenyl ether acrylate isobomyl acrylate 70 39.5 34.5 42.0 39.5 38.5 37.5 34.5 35.5 33.5 30.5 1,10 decanediol diacrvlate 60 1.0 2.0 5.0 iso-octvl acrylate 73 15.0 15.0 13.0 15.0 15.0 15.0 14.0 13.0 12.0 N Vinyl Caprolactam 20.0 25.0 16.0 20.0 20.0 20.0 20.0 20.0 18.0 17.0 cellulose acetate butyrate 40 5.0 Soybean oil, epoxidized, acrylate 85 10.0 15.0 di pentaerythritol hexacrylate tricyclodecanedimethanol diacrylate ethoxylated dipentaerythritol hexaacrylate 2.5 triethylene glycol divinyl ether 2.5 2,4-Diethyl thioxanthone 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 Bis(2,4,6-Trimethylbenzoyl)Phenylphosphine Oxide 4.0 4.0 4.0 4.0 4.0 4.0 4.0 4.0 4.0 4.0 2,4.6-Trimethylbenzoyl-Diphenyl Phosphine Oxide 3.5 3.5 3.5 3.5 3.5 3.5 3.5 3.5 3.5 3.5 Ethyl(2,4,6-Trimethylbenzoyl)-Phenyl Phosphinate stabiliser 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 aliphatic silicon acrylate 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 urethane acrylate 1.5 1.5 2.0 1.5 1.5 1.5 1.5 1.5 1.5 1.5 Acrylated Amine Synergist 4.5 4.5 2.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 cyan pigment dispersion 1 7.5 7.5 7.5 7.5 7.5 7.5 7.5 7.5 7.5 7.5 cyan pigment dispersion 2 Total 100 100 100 100 100 100 100 100 100 100 Material BRC % C-ll C-12 C-13 C-14 C-15 C-16 C-17 C-18 polyester acrylate 46 7.0 ethoxylated TMPTA 12.0 polyethylene glycol 400 diacrylate 14.0 lauryl acrylate 80 12.0 5.0 hexanediol diacrylate 19.2 19.2 2-Phenoxyethylacrylate 34.6 2.0 36.1 Cyclic Trimethylolpropane Formal Acrylate 6.0 19.0 14.5 polyethylene glycol o-phenyl phenyl ether acrylate 7.0 isobornyl acrylate 70 31.5 42.5 15.0 32.0 1.10 decanediol diacrylate 60 8.0 15.0 17.0 30.8 35.8 iso-octyl acrylate 73 15.0 15.0 15.0 N Vinyl Caprolactam 20.0 28.4 26.9 23.5 10.0 cellulose acetate butyrate 40 Soybean oil, epoxidized, acrylate 85 dipentaerythritol hexacrylate 9.5 2.0 tricyclodecanedimethanol diacrylate 5.0 ethoxylated dipentaerythritol hexaacrylate triethylene glycol di vinyl ether 2,4-Diethylthioxanthone 2.5 2.5 1.0 2.0 1.3 2.5 2.5 2.5 Bis(2,4,6-Trimethylbenzoyl)Phenylphosphine Oxide 4.0 4.5 4.6 2.6 4.0 4.0 4.0 2,4.6-Trimethylbenzoyl-Diphenyl Phosphine Oxide 3.5 4.0 4.9 4.9 3.5 3.5 3.5 Ethyl(2,4,6-Trimethylbenzoyl)- Phenyl Phosphinate 4.9 stabiliser 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 aliphatic silicon acrylate 1.0 1.0 1.0 2.0 1.0 1.0 1.0 1.0 urethane acrylate 1.5 2.5 1.0 2.0 1.5 1.5 Acrylated Amine Synergist 4.5 3.5 5.0 4.5 5.0 5.0 cyan pigment dispersion 1 7.5 7.5 7.5 8.1 7.5 7.5 7.5 cyan pigment dispersion 2 9.7 Total 100 100 100 100 100 100 100 100 Table 2: Cyan Dispersion Formulations Milled to D100 <1 micrometer Material cyan dispersion 1 cyan dispersion 2 BRC content, % 2-Phenoxyethylacrylate 54.21 Cyclic Trimethylolpropane Formal Acrylate 51.30 stabiliser 1 0.44 0.44 stabiliser 2 0.18 ~0 stabiliser 3 1.25 1.25 M) stabiliser 4 0.66 EFKA®PX4701 dispersant 14.10 Uj CGPS-392 dispersant 21.17 FASTOGEN® BLUE 543 5K pigment 30.00 ~0 HELIOGEN®BL D 7110 F pigment 25.0 Total 100 100 Results Table 3: Tape Adhesion3 - Ink drawdowns applied using a 12pm K-bar and cured via a 395nm ITL LED lamp. Tape adhesion subsequently assessed using the following scale: 0 = no removal; 10 1 = <5% removal; 2 = 5-15% removal; 3 = 15-35% removal; 4 = 35-65% removal; 5 = >65% removal. Pass = 0-1; fail = >1. Substrate E-l E-2 E-3 E-4 E-5 E-6 E-7 E-8 E-9 E-10 ’Acrylic 0 0 0 0 0 0 1 0 0 1 2DJ vinyl 0 0 0 0 0 0 0 0 1 1 Substrate C-ll C-12 C-13 C-14 C-15 C-16 C-17 C-18 ’Acrylic 5 5 0 4 5 5 5 5 2DJ vinyl 0 5 1 0 5 5 4 4 '3 mm rigid acrylic (Amari Plastics) 2Flcxiblc banner vinyl (Ultraflex Europe) 3Adhesion tested by ISO 2409 “Paints and varnishes - cross-cut test” As shown in Table 3, all Inventive Examples pass the adhesion tests, while all Comparative Examples with the exception of C-13 (which has a negligible BRC content), fail on at least one substrate. This includes all inks prepared with a 1,10 decanediol diacrylate content of >8%. The examples show the benefit that the inclusion of IOA or LA have on the adhesion of the inks. Table 4 : Flexibility - 12pm drawdowns (4 layers) on flexible banner vinyl were prepared and cured using a medium pressure mercury vapor UV H-bulb. Flexibility was assessed on a rating scale of 1-10 one hour after curing. Rating: pass = 0-1; fail = >2. E-l E-2 E-3 E-4 E-5 E-6 E-7 E-8 E-9 E-10 Flexibility^ Rating 1 1 1 1 1 1 1 1 1 1 C-ll C-12 C-13 C-14 C-15 C-16 C-17 C-18 Flexibility Rating 1 0 0 9 0 1 7 7 The flexibility ratings from Table 4 show that all Inventive Examples pass, however some of the comparative examples failed. C-14, 17, 18 did contain significant levels of di- and multi-functional acrylate monomers; C-l 1, 12, 15, 16 failed the adhesion test; C-13 has a negligible BRC content, again highlighting the beneficial effect of IOA and LA. It is also worth noting the performance of Example E-8, which contains cellulose acetate butyrate (CAB). The inclusion of CAB raised the viscosity markedly, which would exclude its use from conventional printheads. However, newer printhead technologies such as the high viscosity capable types being developed by Xaar and other printhead manufacturers would enable the deployment of this invention with ink viscosities up to 100 cP, and conceivably up to 500cP, at application (jetting) temperature. Table 5: Viscosity was measured using a Brookfield DV-II+Pro fitted with a spindle 18, lOOrpm, 45°C. BRC content of the exemplified inks was calculated using information provided by material suppliers but may also be determined using the test method described herein. Example E-l E-2 E-3 E-4 E-5 E-6 E-7 E-8 E-9 E-10 Viscosity (cP) 6.5 6.5 6.5 7.6 6.5 6.6 6.6 84.5 12.4 17.3 BRC % 38.6 35.1 38.9 39.7 38.5 38.4 38.1 37.1 41.4 42.9 Example C-ll C-12 C-13 C-U C-15 C-16 C-17 C-18 Viscosity (cP) 6.9 10.1 9.7 10.3 10.1 7.3 11.8 11.7 BRC % 37.8 52.9 ~0 10.5 ~0 43.6 28.1 25.5 It can be seen that the calculated BRC content is >30% for all Inventive Examples E-1-E10, due largely to the careful choice of acrylate monomer. A number of the comparative examples fall below this threshold. All examples in Table 5, with the exception of E-8, fall in the viscosity range typical of current inkjet formulations. E-8 has been deliberately formulated in order to produce a formulation of a much higher viscosity suitable for more modern inkjet printheads. Thus, the present application is directed to both low viscosity (<20cP) as well as high viscosity (>20cP) inkjet applications. As mentioned previously, although the invention is directed towards energy-curable inkjet compositions suitable for use in conventional printheads, with viscosities of 20 cP or less at 45°C, it also covers compositions with viscosities greater than 20 cP. It further covers compositions having viscosities greater than 50cP, greater than 75cP and compositions with viscosities of lOOcp or greater at 45°C. Note that only Inventive Examples E1-E10 pass adhesion and flexibility tests whilst possessing a BRC content of >30%. Test Methods: BRC content Unless stated otherwise, the BRC content is determined in accordance with ASTM D6866-18 Method B (AMS) using NIST Standard Reference Material (SRM) 4990C. Particle size / average particle size. In the context of the present invention, the terms “particle size” or “average particle size” refer to the volume distributed median particle diameter (equivalent spherical diameter corresponding to 50% of the volume of all the particles, read on the cumulative distribution curve relating volume % to the diameter of the particles - often referred to as the “D(v,0.5)” value). Particle size distributions can be determined by routine laser diffraction techniques. Unless otherwise stated, particle size distribution measurements as specified or reported herein are as measured by Malvern Instruments’ conventional Malvern Mastersizer 3000 particle size analyzer. Adhesion tested by ISO 2409: Paints and varnishes - cross-hatch adhesion test Viscosity tested by Brookfield DV-II+Pro; spindle 18; lOOrpm; 45°C Flexibility Apparatus: RK 101 Automatic Drawdown Coater Rig; 12pm K-Bar; banner vinyl substrate; metal carrier board with two magnetic strips; UV curing rig fitted with H-bulb Procedure: - Use a 12 pm K Bar and RK 101 Automatic Drawdown Coater Rig to produce a print consisting of 4 layers of the same ink on top of each other, curing each layer at 150 mJcm-2 before applying the next. Adjust belt speed to give a cure dose of 200 mJcm2. Pass the print through the cure unit 10 times to give a cumulative dose of 2000 mJ / cm2 Allow the drawdown a minimum of 1 hour to cool before testing. - Bend the drawdown through 180° (so that the ink is facing the outside). Observe any cracking that occurs and rate on the following 0-10 scale. Score Description 0 No change. 1 Wrinkling along fold line. No cracking / other changes. 2 Wrinkling along line, some tiny cracks. 3 A few small cracks. 4 Small-medium cracks covering part of drawdown area. 5 “Crazing” (multiple thin cracks spreading across drawdown area). 6 Severe crazing. 7 One long crack covering breadth of drawdown. 8 Audible cracking. 9 Audible cracking when substrate bent back on itself 10 Parts of cured film stand / flake off substrate when bent

Claims

1. An energy-curable inkjet ink composition, comprising:i) 30-80 wt% monofunctional (meth)acrylate monomers;ii) 5-35 wt% N-vinyl monomer;iii) 10-60% wt% isobornyl acrylate; optionally wherein the isobornyl acrylate has a biorenewable content of at least 60%;iv) 1-25 wt% of one or more monofunctional, linear or branched Ce-Cis alkyl acrylates, optionally wherein the one or more monofunctional, Ce-Cis alkyl acrylates is / are selected from iso-octyl acrylate, lauryl acrylate, and combinations thereof,v) 0-25 wt% acrylated amine; andvi) less than 8 wt% decanediol diacrylate;optionally wherein the composition has >30% biorenewable content.

2. The composition according to claim 1, comprising 40-70 wt% monofunctional (meth)acrylate monomers, optionally 40 to 60 wt%, optionally 40 to 55 wt% monofunctional (meth)acrylate monomers.

3. The composition according to claims 1 or 2, comprising 10-30 wt% N-vinyl monomer, optionally 15 to 25wt% N-vinyl monomer.

4. The composition according to any one of claims 1 to 3, comprising 20-60 wt% isobornyl acrylate, optionally 30-60wt%, optionally 30 to 45 wt% isobornyl acrylate.

5. The composition according to any preceding claim, comprising 1-10 wt% acrylated amine, optionally 3 to 7 wt% acrylated amine.

6. The composition according to any preceding claim, comprising l-25wt% iso-octyl acrylate, optionally 5 to 20 wt%, optionally 10 to 18 wt% iso-octyl acrylate, wherein the iso-octyl acrylate has a biorenewable content in excess of 60wt%.

7. The composition according to any preceding claim, comprising l-25wt% laurylacrylate, optionally 5 to 20 wt%, optionally 10 to 18 wt% lauryl acrylate, wherein the lauryl acrylate has a biorenewable content in excess of 60wt%.

8. The composition according to any preceding claim, comprising 5-20 wt% of any blend of iso-octyl acrylate and lauryl acrylate, optionally 10 to 18 wt%, optionally 12 to 16wt% of any blend of iso-octyl acrylate and lauryl acrylate.

9. The composition of any preceding claim, comprising <7 wt% decanediol diacrylate (DDDA), optionally <6wt% decanediol diacrylate.

10. The composition of any preceding claim, comprising <5 wt% decanediol diacrylate (DDDA), optionally <3 wt%, optionally <2 wt% decanediol diacrylate.

11. The composition of any preceding claim, comprising <1 wt% decanediol diacrylate (DDDA), optionally wherein the composition is substantially free of decanediol diacrylate.

12. The composition of any preceding claim, further comprising 0.1-15 wt% of a cellulose acetate butyrate and / or propionate resin.

13. The composition of any preceding claim, further comprising 0.1-15 wt% of a (meth)acrylated epoxidized soybean oil oligomer.

14. The composition according to any preceding claim, wherein the composition comprises less than 8wt% of monomers having a functionality of 4 or greater, optionally less than 5wt%, optionally less than 2wt% of monomers having a functionality of 4 or greater.

15. The composition according to any preceding claim, wherein the composition comprises less than 2wt% of non-alkoxylated monomers having a functionality of 6 orgreater, optionally less than lwt%, optionally wherein the composition is substantially free of non-alkoxylated monomers having a functionality of 6 or greater.

16. The composition according to any preceding claim, wherein the monofunctional (meth)acrylate monomers have a molecular weight of less than 500 Da, optionally less than 400 Da, optionally less than 300 Da.

17. The composition according to any preceding claim, wherein the compositioncomprises less than 5wt% of 2-phenoxyethylacrylate, cyclic tnmethylolpropane formal acrylate, and combinations thereof, optionally wherein the composition is substantially free of 2-phenoxyethylacrylate, cyclic trimethylolpropane formal acrylate, and combinations thereof.

18. The composition according to any preceding claim, wherein the one or moremonofunctional, linear or branched Q-Cis alkyl acrylates is / are monofunctional, linear or branched Ce-Cis alkyl acrylates wherein the maximum branch length is a ethyl group (-CH2CH3), optionally a methyl group (-CH3).

19. The composition according to any preceding claim, comprising >35% biorenewable content, optionally >40% biorenewable content.

20. The composition of any preceding claim, further comprising one or more photoinitiators.

21. The composition of any preceding claim, further comprising one or more colorants.

22. The composition of claim 21, wherein some or all of the colorants have a biorenewable content of at least 60%.

23. The composition of any preceding claim, wherein the viscosity is <20cP at 45°C.

24. The composition of any preceding claim, wherein the viscosity is >20cP at 45°C.

25. A method of printing, comprising:i) applying the composition of any one or more of claims 1-24 onto a substrate by inkjet deposition; andii) curing.

26. The method of claim 25, wherein the curing is performed using UV-LED27. A printed article comprising the composition of any one or more of claims 1-24.

28. Use of 1-25 wt% of one or more monofunctional, linear or branched Ce-Cis alkylacrylates in an energy-curable inkjet ink composition for the purpose of improving adhesion to substrates, where the composition comprises:i) 30-80 wt% monofunctional (meth)acrylate monomers;ii) 5-35 wt% N-vinyl monomer;iii) 10-60% wt% isobornyl acrylate; optionally wherein the isobornyl acrylate has a biorenewable content of at least 60%;v) 0-25 wt% acrylated amine; andvi) less than 8 wt% decanediol diacrylate;optionally wherein the composition has >30% biorenewable content, optionally wherein the one or more monofunctional, Ce-Cis alkyl acrylates is / are selected from iso-octyl acrylate, lauryl acrylate, and combinations thereof.Application No: GB2412179.0Examiner:Dr Paul MintonClaims searched: 1-28Date of search: 13 December 2024Patents Act 1977: Search Report under Section 17Documents considered to be relevant:Category Relevant to claims Identity of document and passage or figure of particular relevance X 1-5,9- 11,14-16,18,20, 21,25-27 US2022 / 403198 Al (RETAILLEAU et al) see particularly Ink LC in Table 10. X 1-3,9- 11,14- 16,18,20, 21,25-27 US2018 / 112090 Al (WARD et al) see particularly Ink 1 in Table 1. v A 1-3,9- 11,14- 16,18,20, 21,25-27 US2015 / 353751 Al (UMEBAYASHI) see particularly Ink Set 6 in Table 11. X 1-4,7,9- 11,14- 16,18,20, 21,25-27 US2010 / 233448 Al (KAMEYAMA et al) see particularly Examples 1, 4, 8 &12-23. X 1,2,4,6,9-11,14- 18,20,21, 25,27 US2002 / 086914 Al (LEE et al) see particularly Inks 7a-d in Table 7 and Sample A in Table 12. X 1,2,4,6,9-11,14- 18,20,21, 25,27 at least JP2010144149A (SAKATA) see particularly WPI Abstract Accession No. 2010-H57163 and Examples 1, 2 &4.Categories:X Document indicating lack of novelty or inventive step A Document indicating technological background and / or state of the art. Y Document indicating lack of inventive step if P Document published on or after the declared priority date but combined with one or more other documents of same category. before the filing date of this invention. & Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.Field of Search:Search of GB, EP, WO &US patent documents classified in the following areas of the UKCX :27Worldwide search of patent documents classified in the following areas of the IPC____________ C09D___________________________________________________ The following online and other databases have been used in the preparation of this search report SEARCH-PATENT, SEARCH-NPLInternational Classification:Subclass Subgroup Valid From C09D 0011 / 30 01 / 01 / 2014