Radiation curable composition

Abstract

A radiation curable composition comprising at least one urethane-urea oligomer (P) obtained from the reaction of: a) at least one diisocyanate compound (A); b) at least one compound (B) comprising at least one hydroxyl group and further comprising at least one ethylenically unsaturated group; c) at least one polymeric diol (DL); and d) at least one diamine (DM) having a number average molecular weight (Mn) of less than 4000 g / mol; wherein the urethane-urea oligomer (P) comprises at least two urea linkages obtained from the reaction between the at least one diisocyanate compound (A) and the at least one diamine (DM), wherein the urethane-urea oligomer (P) further comprises at least two urethane linkages obtained from the reaction between the at least one diisocyanate compound (A) and the at least one hydroxyl group of the least one compound (B), and wherein the ethylenically unsaturated group(s) are located in the terminal positions of the urethane-urea oligomer (P).

Description

RADIATION CURABLE COMPOSITIONTechnical Field

[0001] The present invention relates to radiation curable compositions which are particularly suitable for use in three-dimensional printing and to articles obtainable from said radiation curable compositions.Background

[0002] Three-dimensional printing techniques have been widely used for the production of three-dimensional articles and objects starting from a digital model. In that context, the so- called vat photopolymerization technique (such as e.g. DLP or SLA), which consists in additive manufacturing through layer-by-layer solidification of liquid polymeric resinous materials by means of radiation curing process using e.g. UV irradiation, has rapidly emerged as a leading technology for high-resolution 3D printing.

[0003] The materials commonly used in vat photopolymerization processes, often referred to as photocurable resins, have long been associated with undesired properties such as brittleness, which make them unsuitable for many applications. Indeed, various industries require high- performance photocurable resins which deliver to the cured material high toughness and high durability. High toughness may only be obtained through the combination of high strength and high flexibility or deformability7.

[0004] Partial solutions are described e.g. in WO 2022 / 051521 (Liu et al.) and in WO 2022 / 157112 (Wu et al.). Without contesting the technical advantages associated with the solutions known in the art, there is still a need for a photocurable material which overcomes at least partially the above-mentioned deficiencies.Summary

[0005] According to one aspect, the present disclosure relates to a radiation curable composition comprising at least one urethane-urea oligomer (P) obtained from the reaction of: a) at least one diisocyanate compound (A); b) at least one compound (B) comprising at least one hydroxyl group and further comprising at least one ethylenically unsaturated group;c) at least one polymeric diol (DL); and d) at least one diamine (DM) having a number average molecular weight (Mn) of less than 4000 g / mol; wherein the urethane-urea oligomer (P) comprises at least two urea linkages obtained from the reaction between the at least one diisocyanate compound (A) and the at least one diamine (DM), wherein the urethane-urea oligomer (P) further comprises at least two urethane linkages obtained from the reaction between the at least one diisocyanate compound (A) and the at least one hydroxyl group of the least one compound (B), and wherein the (at least one) ethylenically unsaturated group(s) are located in the terminal positions of the urethane-urea oligomer (P).

[0006] According to another aspect, the present disclosure is directed to a process for the manufacturing of a radiation curable composition as described above, wherein the process comprises the steps of: a) bringing the at least one diisocyanate compound (A) in presence of the at least one compound (B). the at least one polymeric diol (DL) and the at least one diamine (DM), thereby forming a mixture material comprising (the) at least one urethane-urea oligomer (P); b) optionally, subjecting the mixture material to thermal energy; and c) optionally, subjecting the mixture material to mechanical mixing.

[0007] According to yet another aspect, the present disclosure relates to the use of a radiation curable composition as described above in a three-dimensional printing process, in particular in a three-dimensional printing process using vat (photo)polymerization techniques.Detailed description

[0008] According to first aspect, the present disclosure relates to a radiation curable composition comprising at least one urethane-urea oligomer (P) obtained from the reaction of: a) at least one diisocyanate compound (A); b) at least one compound (B) comprising at least one hydroxyl group and further comprising at least one ethylenically unsaturated group; c) at least one polymeric diol (DL); and d) at least one diamine (DM) having a number average molecular weight (Mn) of less than 4000 g / mol;wherein the urethane-urea oligomer (P) comprises at least two urea linkages obtained from the reaction between the at least one diisocyanate compound (A) and the at least one diamine (DM), wherein the urethane-urea oligomer (P) further comprises at least two urethane linkages obtained from the reaction between the at least one diisocyanate compound (A) and the at least one hydroxyl group of the least one compound (B), and wherein the ethylenically unsaturated groups of the least one compound (B) are located in the terminal positions of the urethane-urea oligomer (P).

[0009] In the context of the present disclosure, it has been surprisingly found that a radiation curable composition as described above is provided with excellent formulation stability, as well as advantageous formulation flexibility. Advantageously, the radiation curable composition of the present disclosure is and remains in the form of a homogeneous (single phase) liquid formulation at room temperature upon prolonged storage. Advantageously still, the radiation curable composition as described herein has excellent thermostability’ characteristics which makes it suitable for various industrial manufacturing processes.

[0010] The urethane-urea oligomer (P) for use in the present radiation curable composition is conveniently obtained using a one-pot synthesis strategy involving successive chemical reactions in just one reactor, thereby avoiding lengthy separation and purification of any intermediate chemical compounds, and thereby improving the overall process efficiency while increasing the overall chemical reaction yield. Advantageously still, the urethane-urea oligomer (P) is obtained without requiring any additional thermal treatment - such as annealing or deblocking steps - at temperatures typically exceeding 100°C, which can substantially deteriorate the overall process efficiency and reproducibility characteristics.

[0011] It has no less surprisingly been found that a radiation curable composition as described above is particularly suitable for forming cured polymeric materials provided with excellent characteristics and performance attributes as regard to mechanical properties, in particular tensile strength, elongation at break and Young’s modulus. This is a particularly surprising and counterintuitive finding considering that obtaining in particular both high tensile strength and high elongation at break is somewhat technically self-contradicting or at least technically challenging to achieve.

[0012] Without wishing to be bound by theory, it is believed that these excellent characteristics and attributes are due in particular to the presence in the urethane-urea oligomer (P) of the at least two urea linkages obtained from the reaction between the at least onediisocyanate compound (A) and the at least one diamine (DM) having a number average molecular weight (Mn) of less than 4000 g / mol, in addition to the at least two urethane linkages obtained from the reaction between the at least one diisocyanate compound (A) and the at least one hydroxyl group of the least one compound (B), and wherein the ethylenically unsaturated group(s) are located in the terminal positions of the urethane-urea oligomer (P). More specifically, it is believed that the urea linkages present in the urethane-urea oligomer (P) contribute to create hard segments within the cured polymeric material through - in particular - the strong hydrogen bonding provided by these urea linkages. The presence of these hard segments are in turn believed to beneficially improve the overall toughness characteristics of the resulting cured polymeric material.

[0013] In the context of the present disclosure, it has been observed that cured polymeric materials resulting from polyurethane-based photocurable resins (i.e. comprising mainly conventional urethane linkages, without any urea linkages) are characterized by sub-optimal structural characteristics, which usually translate into undesired properties such as brittleness and make them unsuitable for some applications. Still without wishing to be bound by theory, it is believed that the presence of the urea linkages, in particular w hen located in the backbone of the urethane-urea oligomer (P). provide the resulting cured polymeric material with more optimal structural characteristics.

[0014] As such, the radiation curable composition of the present disclosure is outstandingly suitable for use in a three-dimensional printing process, in particular in a three-dimensional printing using vat (photo)polymerization techniques.

[0015] It has indeed further been found that a radiation curable composition as described above, when used in three-dimensional printing, provides excellent printing quality and usually much improved printing quality when compared to the use of polyurethane-based photocurable resins. Without wishing to be bound by theory, it is believed that these excellent printing characteristics are again due to the presence of the urea linkages in the urethane-urea oligomer (P), which advantageously impact the adhesion between the successive layers formed during the layer-by-layer solidification steps used during the three-dimensional printing process. This enhanced layer adhesion is believed to be facilitated by the strong hydrogen bonding provided by these urea linkages.

[0016] In a ty pical aspect of the urethane-urea oligomer (P) for use in the radiation curable composition described herein, one ethylenically unsaturated group originating from one compound (B) is located in each terminal position of the urethane-urea oligomer (P).

[0017] In a particular aspect of the radiation curable composition described herein, the at least two urea linkages of the at least one urethane-urea oligomer (P) for use herein are (each) separated from the at least one (terminal) ethylenically unsaturated group(s) by at least one urethane linkage.

[0018] In another particular aspect, the at least two urea linkages of the at least one urethane- urea oligomer (P) are (each) separated from the at least one (terminal) ethylenically unsaturated group(s) by at least one urethane linkage obtained from the reaction between the at least one diisocyanate compound (A) and the at least one hydroxyl group of the least one compound (B).

[0019] In still another particular aspect, at least one of the at least two urea linkages of the at least one urethane-urea oligomer (P) is separated from the at least one (terminal) ethylenically unsaturated group(s) by the at least two urethane linkages, or even at least three urethane linkages.

[0020] According to a particular aspect, the urethane-urea oligomer (P) for use herein further comprises at least two additional urethane linkages obtained from the reaction between the at least one diisocyanate compound (A) and the at least one polymeric diol (DL).

[0021] According to another particular aspect, at least one of the at least two urea linkages of the at least one urethane-urea oligomer (P) is (further) separated from the at least one (terminal) ethylenically unsaturated group(s) by the at least two additional urethane linkages obtained from the reaction between the at least one diisocyanate compound (A) and the at least one polymeric diol (DL).

[0022] According to another typical aspect of the urethane-urea oligomer (P) for use herein, the at least two urea linkages obtained from the reaction between the at least one diisocyanate compound (A) and the at least one diamine (DM) are located in the backbone of the urethane- urea oligomer (P).

[0023] In the context of the present disclosure, the expression '‘the at least two urea linkages are located in the backbone of the urethane-urea oligomer (P)” is meant to express that these at least two urea linkages are not the first functional linkages directly linked to the at least one compound (B) comprising at least one hydroxyl group and further comprising at least one ethylenically unsaturated group.

[0024] According to one advantageous aspect, the urethane-urea oligomer (P) for use herein is represented by the following formula (I) :Hydroxy functional compound (B) - {diisocyanate compound (A) - polymeric diol (DL)}m- {diisocyanate compound (A) - diamine (DM)}n- diisocyanate compound (A)- Hydroxy functional compound (B)(I) wherein: m and n are integers independently selected from 1 to 5. or even from 1 to 3.

[0025] According to another advantageous aspect, the urethane-urea oligomer (P) for use herein is represented by the following formula (II):Hydroxy functional compound (B) - diisocyanate compound (A) - polymeric diol (DL)- diisocyanate compound (A) - diamine (DM) - diisocyanate compound (A) - Hydroxy functional compound (B)(II)

[0026] According to still another advantageous aspect, the urethane-urea oligomer (P) for use herein is represented by the following formula (III):[K]-O(O)C{-N(H)-[E]-N(H)-C(O)O-[G]-O(O)C}m{-N(H)-[E]-N(H)-C(O)-N(H)-[J]-N(H)-C(O)}n-N(H)-[E]-N(H)-C(O)O-[K](III) wherein:Kis the residue of compound (B);E is the residue of the diisocyanate compound (A);G is the residue of the polymeric diol (DL);J is the residue of the diamine (DM); and m and n are integers independently selected from 1 to 5, or even from 1 to 3.

[0027] According to yet another advantageous aspect, the urethane-urea oligomer (P) for use herein is represented by the following formula (IV):[K]-O(O)C-N(H)-[E]-N(H)-C(O)O-[G]-O(O)C-N(H)-[E]-N(H)-C(O)-N(H)-[J]-N(H)-C(O)-N(H)-[E]-N(H)-C(O)O-[K](IV)wherein:Kis the residue of compound (B);E is the residue of the diisocyanate compound (A);G is the residue of the polymeric diol (DL); and J is the residue of the diamine (DM).

[0028] In a particular aspect of the radiation curable composition described herein, the at least one urethane-urea oligomer (P) has a number average molecular weight (Mn) in a range from 1500 to 15000 g / mol, from 1500 to 10000 g / mol, from 1500 to 8000 g / mol, from 2000 to 8000 g / mol, or even from 2000 to 6000 g / mol.

[0029] The urethane-urea oligomer (P) for use in the radiation curable composition of the present disclosure is obtained from a reaction using, as a first component, at least one diisocyanate compound (A).

[0030] Diisocyanate compounds (A) for use herein are not particularly limited. Any diisocyanate compounds (A) commonly known in the art may be used in the context of the present disclosure. Suitable diisocyanate compounds (A) for use herein will be easily identified by those skilled in the art in the light of the present disclosure.

[0031] According to an exemplary aspect, the diisocyanate compound (A) for use herein is selected from the group consisting of aliphatic diisocyanates, cycloaliphatic diisocyanates, aromatic diisocyanates, and any combinations or mixtures thereof.

[0032] In the context of the present disclosure, it has been surprisingly found that the use of cyclic diisocyanate compounds (A) in the manufacturing of the urethane-urea oligomer (P), advantageously impacts the mechanical properties - in particular tensile strength and elongation at break - of the cured polymeric material resulting from the curing of the radiation curable composition, when compared to non-cyclic diisocyanate compounds (A). Without wishing to be bound by theory, it is believed that the use of diisocyanate compounds (A) having a cyclic structure, such as cycloaliphatic diisocyanates or aromatic diisocyanates, advantageously contribute to create harder segments within the cured polymeric material without sacrificing its overall flexibility characteristics.

[0033] According to an advantageous aspect, the diisocyanate compound (A) for use herein is selected from the group consisting of 1.6-diisocyanatohexane (HDI). 1,1 '-methylene bis [4- isocyanatocyclohexane] (H12MDI), 5-isocyanato-l-isocyanatomethyl-l,3,3- trimethylcyclohexane (isophorone diisocyanate, IPDI), 1,4-diisocyanatobenzene (BDI), 2,4-diisocyanatotoluene (TDI), IJ’-methylene bis[4-isocyanatobenzene] (MDI), xylilenediisocyanate (XDI), tetramethylxylilene diisocyanate (TMXDI), 1,5-naphtalene diisocyanate (NDI), tolidine diisocyanate (TODI), p-phenylene diisocyanate (PPDI), and any mixtures thereof.

[0034] According to more advantageous aspect, the diisocyanate compound (A) is selected from the group consisting of isophorone diisocyanate (IPDI), tetramethylxylilene diisocyanate (TMXDI), 1,1 ’-methylene bis[4-isocyanatocyclohexane] (H12MDI), and any mixtures thereof.

[0035] According to a particularly advantageous aspect, the diisocyanate compound (A) is selected to be tetramethylxylilene diisocyanate (TMXDI). The use of tetramethylxylilene diisocyanate as the diisocyanate compound (A) has been surprisingly found to provide exceptionally good shelf stability upon prolonged storage, as well as excellent thermostability characteristics to the resulting radiation curable composition.

[0036] The urethane-urea oligomer (P) for use in the radiation curable composition of the present disclosure is obtained from a reaction further using at least one compound (B) comprising at least one hydroxyl group and further comprising at least one ethylenically unsaturated group.

[0037] Compounds (B) for use herein are not particularly limited, as long as they comprise at least one hydroxyl group and further at least one ethylenically unsaturated group. Suitable diisocyanate compounds (B) for use herein will be easily identified by those skilled in the art in the light of the present disclosure.

[0038] In an exemplary aspect of the present disclosure, the at least one ethylenically unsaturated group of the compound (B) is selected from the group consisting of (meth)acryloyl, (meth)acrylamide, vinyl, vinylether, allyl, styrenyl. methylstyrenyl, maleyl , fumaryl functional groups, and any combinations or mixtures thereof.

[0039] In an advantageous aspect, the at least one ethylenically unsaturated group of the compound (B) is selected from the group consisting of (meth)acryloyl groups. According to this advantageous aspect, the compound (B) for use herein is an hydroxy functional (meth)acrylic compound.

[0040] In another advantageous aspect, the compound (B) comprises (essentially) one hydroxyl group.

[0041] According to one particular aspect, the compound (B) for use herein is selected from the group consisting of (partial) esterification products obtained from the reaction of at least one ethylenically unsaturated carboxylic acid with at least one aliphatic and / or aromatic polyol, wherein the (partial) esterification products have a residual average hydroxyl functionality of about 1.

[0042] According to another particular aspect, the compound (B) for use herein is selected from the group consisting of (partial) esterification products obtained from the reaction of at least one aliphatic and / or aromatic polyol with (meth)acrylic acid, wherein the (partial) esterification products have a residual average hydroxyl functionality of about 1.

[0043] According to an advantageous aspect of the disclosure, the at least one compound (B) is selected from the group consisting of hydroxy alkyl(meth)acrylates having from 1 to 20, from 1 to 15, from 1 to 10 or even from 1 to 5 carbon atoms in the alkyl group.

[0044] According to a more advantageous aspect, the compound (B) is selected from the group consisting of hydroxy ethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, and any mixtures thereof.

[0045] According to a particularly advantageous aspect, the compound (B) for use in the disclosure is selected from the group consisting of 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, and any mixtures thereof.

[0046] In a typical aspect of the disclosure, the at least one compound (B) for use herein may be referred to as a reactive end-capping agent.

[0047] The urethane-urea oligomer (P) for use in the radiation curable composition of the present disclosure is obtained from a reaction further using at least one polymeric diol (DL).

[0048] Polymeric diols (DL) for use herein are not particularly limited. Any polymeric diols (DL) commonly known in the art may be used in the context of the present disclosure. Suitable polymeric diols (DL) for use herein will be easily identified by those skilled in the art in the light of the present disclosure.

[0049] In an exemplary aspect of the present disclosure, the polymeric diol (DL) for use herein is selected from the group consisting of polyether diols, polyester diols, in particular poly caprolactone diols, polycarbonate diols, (hydrogenated) polybutadiene diols, polyacrylate diols, polyacrylic diols, and any combinations or mixtures thereof.

[0050] In an advantageous aspect, the at least one polymeric diol (DL) is selected from polyether diols, in particular from the group consisting of poly (tetramethylene ether) glycol (PTMG). poly(trimethylene ether) glycol (PO3G), polypropylene glycol (PPG), and any combinations thereof.

[0051] In a more advantageous aspect, the at least one polymeric diol (DL) is selected from the group consisting of poly(tetramethylene ether) glycol (PTMG), poly(trimethylene ether) glycol (PO3G), and any combinations thereof.

[0052] In another advantageous aspect of the disclosure, the at least one polymeric diol (DL) has a number average molecular weight (Mn) in a range from 200 to 10000 g / mol, from 250 to 8000 g / mol, from 500 to 6000 g / mol, from 500 to 5000 g / mol, from 500 to 4000 g / mol. from 500 to 3000 g / mol, from 1000 to 3000 g / mol, or even from 1500 to 2500 g / mol.

[0053] The urethane-urea oligomer (P) for use in the radiation curable composition of the present disclosure is obtained from a reaction further using at least one diamine (DL) having a number average molecular weight (Mn) of less than 4000 g / mol.

[0054] Diamines (DM) for use herein are not particularly limited as long as they have a number average molecular weight (Mn) of less than 4000 g / mol. Any diamines (DM) commonly known in the art and having a number average molecular weight (Mn) of less than 4000 g / mol may be used in the context of the present disclosure. Suitable diamines (DM) for use herein will be easily identified by those skilled in the art in the light of the present disclosure.

[0055] In the context of the present disclosure, it has been surprisingly found that a radiation curable composition comprising at least one urethane-urea oligomer (P) obtained from a reaction using at least one diamine (DL) having a number average molecular weight (Mn) of less than 4000 g / mol is particularly advantageous for forming cured polymeric materials provided with excellent characteristics and performance attributes as regard to mechanical properties, in particular tensile strength and Young’s modulus.

[0056] According to an advantageous aspect, the at least one diamine (DM) for use herein has a number average molecular weight (Mn) of less than 3000 g / mol, less than 2500 g / mol, less than 2000 g / mol, less than 1000 g / mol, less than 500 g / mol, less than 400 g / mol, less than 300 g / mol, less than 250 g / mol, less than 200 g / mol, or even less than 150 g / mol.

[0057] According to a more advantageous aspect, the at least one diamine (DM) for use herein has a number average molecular weight (Mn) in a range from 100 to 3800 g / mol, from 100 to 3500 g / mol, from 100 to 3000 g / mol, from 100 to 2500 g / mol. from 100 to 2000 g / mol. from100 to 1500 g / mol, from 100 to 1000 g / mol, from 100 to 800 g / mol, from 100 to 600 g / mol, from 100 to 500 g / mol. from 100 to 400 g / mol, from 100 to 300 g / mol, from 100 to 250 g / mol, or even from 100 to 200 g / mol.

[0058] According to an exemplary aspect, the at least one diamine (DM) for use herein is selected from the group consisting of aliphatic diamines, cycloaliphatic diamines, aromatic diamines, poly ether diamines, and any combinations or mixtures thereof.

[0059] In the context of the present disclosure, it has been surprisingly found that the use of (bi)cyclic diamines (DM) in the manufacturing of the urethane-urea oligomer (P), advantageously impacts the mechanical properties - in particular tensile strength and elongation at break - of the cured polymeric material resulting from the curing of the radiation curable composition, when compared to non-cyclic diamines (DM). Without wishing to be bound by theory, it is believed that the use of diamines (DM) having a (bi)cyclic structure, such as cycloaliphatic diamines, advantageously contribute to create harder segments within the cured polymeric material without sacrificing its overall flexibility characteristics.

[0060] According to an advantageous aspect, the at least one diamine (DM) for use herein is selected from the group of cycloaliphatic diamines, in particular from the group consisting of bicycloaliphatic diamines, more in particular from the group consisting of 4,4'-methylene bis(cyclohexylamine); 4,4-trimethylenedipiperidine; 1.3-bis (aminomethyl) cyclohexane; and any mixtures thereof.

[0061] According to a particularly advantageous aspect, the at least one diamine (DM) for use in the present disclosure is selected to be 4,4'-methylene bis(cyclohexylamine).

[0062] In another advantageous aspect of the disclosure, the at least one diamine (DM) is selected from the group of non-poly meric diamines.

[0063] In an alternatively advantageous aspect of the disclosure, the at least one diamine (DM) is selected from the group of polyether diamines, in particular from the group consisting of polyethylene glycol diamines having a number average molecular weight (Mn) in a range from 200 to 10000 g / mol.

[0064] As will be easily apparent to those skilled in the art, the molar ratios of components (A), (B), (DL) and (DM) are chosen to result (predominantly) in the at least one urethane-urea oligomer (P) as described above. Selecting suitable molar ratios of components (A), (B), (DL) and (DM) for obtaining a urethane-urea oligomer (P) as described hereinbefore is well withinthe capabilities of the skilled person in the light of the present disclosure, and without exercising any inventive skills.

[0065] In an advantageous aspect of the disclosure, the molar ratio of components (A), (B),(DL) and (DM) is respectively in a range from l:l:l:l to 5: l: l: l, from 1: 1 : 1: 1 to 4: 1 : 1: 1. from 1 : 1: 1 : 1 to 3: 1 : 1: 1, from 1.5:1:1:1 to 3:1: 1:1, from 2: l : l : l to 3: 1 : 1: 1, or even from 2.5: 1 : 1: 1 to 3:1: 1:1.

[0066] In another advantageous aspect, the molar ratio of components (A), (B), (DL) and(DM) is about 3 : 1 : 1 : 1.

[0067] According to an advantageous aspect, the at least one urethane-urea oligomer (P) for use in the present disclosure has a double bond content (DBC) greater than 0.45 mol / kg. As will be easily apparent to those skilled in the art, the double bond content of the urethane-urea oligomer (P) is calculated according to the following equation:Double bond content = mol of acrylate groups / total mass (in kg) of the reactants used to prepare the urethane-urea oligomer (P).

[0068] In the context of the present disclosure, it has been surprisingly found that a radiation curable composition comprising at least one urethane-urea oligomer (P) which has a double bond content (DBC) greater than 0.45 mol / kg is particularly advantageous for forming cured polymeric materials provided with excellent characteristics and performance attributes as regard to mechanical properties, in particular tensile strength and Young's modulus.

[0069] According to a more advantageous aspect, the at least one urethane-urea oligomer (P) for use in the present disclosure has a double bond content (DBC) greater than 0.50 mol / kg, greater than 0.55 mol / kg, greater than 0.60 mol / kg, greater than 0.65 mol / kg, or even greater than 0.70 mol / kg.

[0070] In another beneficial aspect, the at least one urethane-urea oligomer (P) for use herein is obtained without using any amino-functional compound with an amino functionality7greater than 2, or even greater than 3. In a particularly beneficial aspect, the at least one urethane-urea oligomer (P) for use herein is obtained without using any amino-functional compound with an amino functionality between 3 and 4.

[0071] In other words, and according to the above-described beneficial aspect, the reaction mixture used for preparing the at least one urethane-urea oligomer (P) is substantially free of any amino-functional compound with an amino functionality greater than 2, or even greaterthan 3, in particular substantially free of any amino-functional compound with an amino functionality between 3 and 4.

[0072] In still another beneficial aspect, the at least one urethane-urea oligomer (P) for use herein is obtained without using any hydroxy-functional compound with an hydroxyl functionality greater than 2, or even greater than 3. In a particularly beneficial aspect, the at least one urethane-urea oligomer (P) for use herein is obtained without using any hydroxyfunctional compound with an hydroxyl functionality' between 3 and 4.

[0073] In other words, and according to the above-described beneficial aspect, the reaction mixture used for preparing the at least one urethane-urea oligomer (P) is substantially free of any hydroxy -functional compound with an hydroxyl functionality greater than 2, or even greater than 3, in particular substantially free of any hydroxy-functional compound with an hydroxyl functionality between 3 and 4.

[0074] Without wishing to be bound by theory, it is believed that using a reaction mixture for preparing the at least one urethane-urea oligomer (P) which is substantially free of any amino- and / or hydroxy-functional compound with an amino and / or hydroxyl functionality' greater than 2 will result into a urethane-urea oligomer provided with advantageous linearity’ (unbranching) characteristics which will ultimately translate into advantageous performance attributes as regard to mechanical properties.

[0075] In a typical aspect, the radiation curable composition of the present disclosure may further comprise a radiation sensitive polymerization initiator. Suitable radiation sensitive polymerization initiators for use herein are not particularly limited and will be easily identified by those skilled in the art in the light of the present disclosure. Any radiation sensitive polymerization initiators commonly known in the art may be used in the context of the present disclosure.

[0076] Such an initiator may be desirable for assisting in curing of the radiation curable composition. Advantageously, the radiation sensitive polymerization initiator for use herein is a photoinitiator, which therefore absorbs radiation, for example, UV light radiation of sufficient wavelength and intensity to create free radical species and initiate curing of the curable components of the radiation curable composition.

[0077] Radiation sensitive polymerization initiators for use herein are commercially available under the trade designations of IRGACURE® and DAROCUR® from BASF. Specific examples of suitable radiation sensitive polymerization initiators include 1 - hydroxy -cyclohexyl - phenyl - ketone (available as BASF IRGACURE® IC-184). Other exemplary radiation sensitive polymerization initiators for use herein are amply described e.g. in US 2018 / 0100073-Al (Chopra et al.).

[0078] The radiation sensitive polymerization initiator may be present in any suitable or desired amount. In a typical aspect of the disclosure, the total amount of radiation sensitive polymerization initiator included in the radiation curable composition is a range from 0.5 to 15 wt.%, from 1 to 10 wt.%, or even from 1 to 5 wt.%, based on the total weight of the radiation curable composition.

[0079] As is customary in the field, the radiation curable composition of the present disclosure may further comprise additional radiation polymerizable compounds in order to adjust certain properties or performance attributes, and meet the requirements of specifically targeted applications.

[0080] According to one particular aspect, the radiation curable composition further comprises at least one reactive diluent (T). Suitable reactive diluents (T) for use herein are not particularly limited and will be easily identified by those skilled in the art in the light of the present disclosure.

[0081] The reactive diluent (T) for use herein may be typically selected from the group consisting of monofunctional (meth)acrylate monomers, difunctional (meth)acrylate monomers, trifunctional (meth)acrylate monomers, tetrafunctional (meth)acrylate monomers, pentafunctional (meth)acrylate monomers, and any mixtures thereof. Exemplar}' reactive diluents (T) for use herein are described e.g. in US 2018 / 0100073-Al (Chopra et al.). In the context of the present disclosure, the reactive diluent (T) may also be referred to as a radiation polymerizable monomer.

[0082] According to an advantageous aspect, the at least one reactive diluent (T) for use herein has a glass transition temperature greater than 70°C, greater than 80°C, greater than 90°C, greater than 100°C, greater than 110°C, greater than 120°C, or even greater than 130°C, when measured by Dynamic Mechanical Analysis (DMA).

[0083] In the context of the present disclosure, it has been surprisingly found that the use of reactive diluents (T) having a glass transition temperature greater than 70°C in the manufacturing of the urethane-urea oligomer (P). advantageously impacts the mechanical properties - in particular tensile strength and Young’s modulus - of the cured polymeric material resulting from the curing of the radiation curable composition.

[0084] In an advantageous aspect, the at least one reactive diluent (T) for use herein comprises a N-vinyl amide moiety. In the context of the present disclosure, it has been indeed surprisingly found that the use of reactive diluents (T) comprising a N-vinyl amide moiety, not only advantageously impacts the mechanical properties of the resulting cured polymeric material, but also provide outstanding solubility characteristics to the radiation curable composition. Still without wishing to be bound by theory, it is further believed that these excellent solubility characteristics are facilitated by the relatively high polarity, high dilution power and superior ability to reduce viscosity build-up attributed to the N-vinyl amide moiety present in the reactive diluent (T).

[0085] In a more advantageous aspect, the at least one reactive diluent (T) for use herein has the following general formula (V):(L)CON(CH=CH2)(Q) (V) wherein:L is a linear, branched or cyclic hydrocarbon radical, optionally substituted by alkyl, hydroxyl or alkoxy groups and / or interrupted by oxygen or nitrogen atoms;Q is a linear, branched or cyclic hydrocarbon radical, optionally substituted by alkyl, hydroxyl or alkoxy groups and / or interrupted by oxygen or nitrogen atoms; and optionally, L and Q may be covalently linked such as to form a link or a cyclic structure.

[0086] In an even more advantageous aspect, the at least one reactive diluent (T) for use herein has the following general formula (VI):wherein:X is an oxygen or carbon atom;R is an alkyl, hydroxyl or alkoxy group; and n is an integer from 0 to 6, from 0 to 5, from 0 to 4, from 0 to 3, or even from 0 to 2.

[0087] In still another more advantageous aspect of the present disclosure, the at least one reactive diluent (T) is selected from the group consisting of N-vinyl pyrrolidone; N-vinyl caprolactam; N-vinyl-5-methyl oxazolidinone; N-vinyl formamide; and any mixtures thereof.

[0088] In a particularly advantageous aspect of the present disclosure, the at least one reactive diluent (T) is selected from the group consisting of N-vinyl-5-methyl oxazolidinone; N-vinyl caprolactam; and any mixtures thereof.

[0089] In an advantageous aspect, the radiation curable composition of the disclosure comprises from 20 to 80 wt.%, from 30 to 80 wt.%, from 40 to 80 wt.%, from 40 to 75 wt.%, from 45 to 75 wt.%, from 50 to 75 wt.%, from 50 to 70 wt.%, from 55 to 70 wt.%, or even from 55 to 65 wt.%, of the (at least one) urethane-urea oligomer (P), based on the total weight of the radiation curable composition.

[0090] In another advantageous aspect of the disclosure, the radiation curable composition as described herein comprises from 20 to 60 wt.%, from 30 to 60 wt.%, from 30 to 55 wt.%, from 35 to 55 wt.%, from 35 to 50 wt.%, or even from 35 to 45 wt.%, of the (at least one) reactive diluent (T), based on the total weight of the radiation curable composition.

[0091] According to still another advantageous aspect, the radiation curable composition according to the disclosure comprises: a) from 20 to 80 wt.%, from 30 to 80 wt.%. from 40 to 80 wt.%. from 40 to 75 wt.%, from 45 to 75 wt.%, from 50 to 75 wt.%, from 50 to 70 wt.%, from 55 to 70 wt.%, or even from 55 to 65 wt.%, of the (at least one) urethane-urea oligomer (P); b) from 20 to 60 wt.%, from 30 to 60 wt.%, from 30 to 55 wt.%. from 35 to 55 wt.%, from 35 to 50 wt.%, or even from 35 to 45 wt.%, of the (at least one) reactive diluent (T); and c) optionally, from 0 to 5 wt.%, from 0.5 to 5 wt.%, or even from 1 to 5 wt.%, of a radiation sensitive polymerization initiator; wherein the wt.% are based on the total weight of the radiation curable composition.

[0092] According to a particular aspect, the radiation curable composition of the disclosure further comprises additional oligomers including, but not limited to, epoxy acrylate oligomers, polyester acrylate oligomers, urethane acrylate oligomers, amino acrylate oligomers, and any combinations or mixtures thereof.

[0093] As is customary7in the field, the radiation curable composition of the present disclosure may further comprise additional compounds, as optional additives. These include, but are not limited to. chain extenders, anti-oxidants, crosslinking agents, dyes, fillers, modifiers, stabilizers, inhibitors, adhesion promotors, and any combinations or mixtures thereof.

[0094] In a typical aspect, the radiation curable composition as described herein is (substantially) non-aqueous.

[0095] In another typical aspect of the disclosure, the radiation curable composition is (substantially) 100% solid.

[0096] The radiation curable composition of the present disclosure is provided with advantageous viscosity characteristics which makes it particularly suited for use in a three- dimensional printing process, in particular in a three-dimensional printing process using vat (photo)polymerization techniques.

[0097] In a typical aspect, the radiation curable composition as described herein has a viscosity no greater than 5000 mPa-s, no greater than 4500 mPa-s. no greater than 4000 mPa-s. no greater than 3500 mPa-s, no greater than 3000 mPa-s, no greater than 2500 mPa-s, no greater than 2000 mPa-s, no greater than 1800 mPa-s, no greater than 1600 mPa-s, no greater than 1500 mPa-s, no greater than 1400 mPa-s, no greater than 1300 mPa-s, or even no greater than 1200 mPa-s, when measured at 60°C according to the test method described in the experimental section.

[0098] In another typical aspect, the radiation curable composition as described herein has a viscosity in a range from 500 to 5000 mPa-s, from 500 to 4000 mPa-s, from 1000 to 4000 mPa-s, from 1000 to 3500 mPa-s, from 1000 to 3000 mPa-s, from 1000 to 2500 mPa-s, from 1000 to 2000 mPa-s, from 1000 to 1800 mPa-s, from 1000 to 1600 mPa-s, or even from 1000 to 1400 mPa-s, when measured at 60°C according to the test method described in the experimental section.

[0099] In still another typical aspect, the radiation curable composition as described herein has a viscosity no greater than 20000 mPa-s, no greater than 15000 mPa-s, no greater than 10000 mPa-s, no greater than 8000 mPa-s, no greater than 7000 mPa-s, no greater than 6000 mPa-s, no greater than 5000 mPa s, no greater than 4000 mPa s, no greater than 3000 mPa-s, or even no greater than 2500 mPa-s, when measured at 25°C according to the test method described in the experimental section.

[0100] In yet another ty pical aspect, the radiation curable composition as described herein has a viscosity in a range from 500 to 20000 mPa-s, from 500 to 15000 mPa s, from 500 to 15000 mPa-s, from 1000 to 15000 mPa s. from 1000 to 10000 mPa-s, from 1500 to 8000 mPa s. from 1500 to 6000 mPa-s, from 1500 to 5000 mPa-s, from 1500 to 4000 mPa-s, from 2000 to 4000 mPa-s, or even from 2000 to 3000 mPa-s, when measured at 25°C according to the test method described in the experimental section.

[0101] As mentioned hereinbefore, the radiation curable composition of the present disclosure is outstandingly suitable for use in various technical applications.

[0102] In one advantageous aspect, the radiation curable composition of the present disclosure is for use in a three-dimensional printing process, in particular in a three-dimensional printing process using vat (photo)polymerization techniques, more in particular using digital light processing (DLP) techniques.

[0103] In another advantageous aspect, the radiation curable composition of the present disclosure is for use in a coating process.

[0104] In still another advantageous aspect, the radiation curable composition of the present disclosure is for use in an adhesion or sealing process.

[0105] In yet another advantageous aspect, the radiation curable composition as described herein is for the manufacturing of an adhesive or sealant composition.

[0106] The radiation curable composition of the present disclosure may be easily obtained according to manufacturing techniques and processes well known to those skilled in the art. Suitable techniques and processes for obtaining the radiation curable composition are not particularly limited and will be easily identified by those skilled in the art in the light of the present disclosure.

[0107] According to another aspect, the present disclosure relates to a urethane-urea oligomer (P) as described hereinbefore.

[0108] All the particular and advantageous aspects described hereinbefore with respect to the radiation curable composition - in particular the diisocyanate compound (A), the compound (B), the polymeric diol (DL) and the diamine (DM) - are fully applicable to the urethane-urea oligomer (P) according to the present disclosure.

[0109] According to another aspect, the present disclosure is directed to a process for the manufacturing of a radiation curable composition as described above, wherein the process comprises the steps of: a) bringing the at least one diisocyanate compound (A) in presence of the at least one compound (B), the at least one polymeric diol (DL) and the at least one diamine (DM), thereby forming a mixture material comprising (the) at least one urethane-urea oligomer (P); b) optionally, subjecting the mixture material to thermal energy; and c) optionally, subjecting the mixture material to mechanical mixing.

[0110] In a typical aspect of the process for the manufacturing of a radiation curable composition, the molar ratios of components (A), (B), (DL) and (DM) are chosen to result in the at least one urethane-urea oligomer (P) as described hereinbefore.

[0111] In one particular aspect, the step of bringing the at least one diisocyanate compound (A) in presence of the at least one compound (B), the at least one polymeric diol (DL) and the at least one diamine (DM) is performed according to the successive steps of adding first the diisocyanate compound (A), then the compound (B), then the polymeric diol (DL), and then the diamine (DM) into a suitable reactor.

[0112] In one beneficial aspect, the mixture material comprising the urethane-urea oligomer (P) and formed by bringing the at least one diisocyanate compound (A) in presence of the at least one compound (B), the at least one polymeric diol (DL) and the at least one diamine (DM), is subject to the application of thermal energy, in particular heat. This is in particular advantageous to improve the solubilization and reactivity characteristics of the various reactants. In a typical aspect, the mixture material is subject to a thermal treatment at a temperature in a range from 50 to 100°C, from 55 to 95°C, or even from 60 to 90°C.

[0113] In another beneficial aspect, the mixture material is subject to mechanical mixing. This is similarly advantageous to improve the solubilization and reactivity characteristics of the various reactants.

[0114] According to a typical aspect, the process of the present disclosure further comprises the step of incorporating a radiation sensitive polymerization initiator into the mixture material.

[0115] In a particular aspect, the process of the present disclosure further comprises the steps of incorporating at least one reactive diluent (T) as described hereinbefore, into the mixturematerial. Advantageously, the at least one reactive diluent (T) is incorporated into the mixture material (immediately) prior to the step of incorporating the at least one diamine (DM).

[0116] According to still another aspect, the present disclosure is directed to a process for the manufacturing of a urethane-urea oligomer (P) as described hereinbefore, wherein the process comprises the steps of a) bringing the at least one diisocyanate compound (A) in presence of the at least one compound (B), the at least one polymeric diol (DL) and the at least one diamine (DM), thereby forming a mixture material comprising (the) at least one urethane-urea oligomer (P); b) optionally, subjecting the mixture material to thermal energy: and c) optionally, subjecting the mixture material to mechanical mixing.

[0117] In a typical aspect of the process for the manufacturing of a urethane-urea oligomer (P), the molar ratios of components (A), (B), (DL) and (DM) are chosen to result in the at least one urethane-urea oligomer (P) as described hereinbefore.

[0118] All the particular and advantageous aspects described hereinbefore with respect to the process for the manufacturing of a radiation curable composition - in particular the step of bringing the at least one diisocyanate compound (A) in presence of the at least one compound (B), the at least one polymeric diol (DL) and the at least one diamine (DM), and the optional steps of subjecting the mixture material to thermal energy and / or mechanical mixing - are fully applicable to the process for the manufacturing of a urethane-urea oligomer (P) according to the present disclosure.

[0119] According to yet another aspect, the present disclosure relates to a resin composition produced by a process as described hereinbefore.

[0120] According to yet another aspect, the present disclosure is directed to a process of making a cured polymeric material, comprising the steps of: a) providing a radiation curable composition as described above; and b) exposing the radiation curable composition to actinic radiation.

[0121] The actinic radiations used for curing preferably are ultraviolet rays, electron beam, X-rays, radioactive rays or high frequency waves. Ultraviolet rays having a wavelength of from 180 to 400 nm are particularly preferred from economical viewpoint. Curing by irradiation may be followed by thermal curing in the presence of suitable external (thermal) crosslinkers.

[0122] In a ty pical aspect, the radiation curable compositions as described above are cured by ultraviolet irradiation, in the presence of a photo-initiator.

[0123] In still another aspect of the disclosure, it is provided a process of making a three- dimensional article, comprising the steps of a) providing a radiation curable composition as described above; b) exposing the radiation curable composition to actinic radiation thereby forming a cured cross-section; and c) repeating steps (a) and (b) thereby resulting in a (cured) three-dimensional article.

[0124] In a typical aspect, the process of making a three-dimensional article comprises vat (photo)polymerization processing steps.

[0125] In still another aspect of the disclosure, it is provided a process of coating an object or a substrate, comprising the steps of a) providing a radiation curable composition as described above; b) applying the composition onto at least part of the surface of the object or the substrate; and c) curing the composition by subjecting the coated surface to actinic radiation (in particular UV, UV-LED or e-beam).

[0126] All the particular and advantageous aspects described hereinbefore with respect to the radiation curable composition - in particular the diisocyanate compound (A), the compound (B), the polymeric diol (DL), the diamine (DM) and the optional reactive diluent (T) - are fully applicable to the various process as described hereinbefore and which are according to the present disclosure.

[0127] In yet another aspect of the disclosure, it is provided a cured polymeric material produced by any one of the various processes described hereinbefore.

[0128] In one advantageous aspect, the cured polymeric material has an elongation at break value greater than 50 %, greater than 80 %, greater than 100 %, greater than 120 %, greater than 140 %, greater than 160 %, greater than 180 %, greater than 200 %, greater than 220 %, greater than 250 %, greater than 260 %, greater than 280 %. or even greater than 300 %, when measured according to the test method described in the experimental section.

[0129] In another advantageous aspect, the cured polymeric material as described above has tensile strength value greater than 5 MPa. greater than 10 MPa, greater than 15 MPa. greaterthan 18 MPa, greater than 20 MPa, greater than 22 MPa, greater than 25 MPa, greater than 28 MPa, greater than 30 MPa, greater than 32 MPa, greater than 34 MPa, greater than 36 MPa, greater than 38 MPa, or even greater than 40 MPa. when measured according to the test method described in the experimental section.

[0130] In still another advantageous aspect, the cured polymeric material has a Young's modulus value greater than 50 MPa, greater than 100 MPa, greater than 200 MPa, greater than 300 MPa, greater than 400 MPa, greater than 500 MPa, greater than 600 MPa, greater than 700 MPa, greater than 800 MPa, greater than 900 MPa, greater than 1000 MPa, greater than 1200 MPa. greater than 1250 MPa, or even greater than 1300 MPa. when measured according to the test method described in the experimental section.

[0131] According to an advantageous aspect, the cured polymeric material as described above is selected from the group consisting of cured three-dimensional articles, cured coatings, cured adhesive compositions and cured sealing compositions.

[0132] According to another aspect, the present disclosure relates to the use of a radiation curable composition or a urethane-urea oligomer (P) as described above in a three-dimensional printing process, in particular in a three-dimensional printing process using vat (photo)polymerization techniques, more in particular using digital light processing (DLP) techniques.

[0133] According to still another aspect, the present disclosure relates to the use of a radiation curable composition or a urethane-urea oligomer (P) as described above for the manufacturing of a coating or in a coating process.

[0134] According to still another aspect, the present disclosure relates to the use of a radiation curable composition or a urethane-urea oligomer (P) as described above for the manufacturing of an adhesive or sealant composition, or in an adhesion or sealing process.EXAMPLES

[0135] The present disclosure is further illustrated by the following examples. These examples are merely for illustrative purposes only and are not meant to be limiting on the scope of the appended claims.

[0136] Throughout the present disclosure and example section, the following test and measurement methods are used to characterize the exemplary radiation curable compositions and the cured polymeric material obtained therefrom.Test Methods:A) Molecular weight

[0137] The number-average molecular weight (Mn) is determined by conventional gel permeation chromatography (GPC) with Polystyrene standards EasyCal from Agilent (Molecular Weight range: 370 - 110,500 g / mol). The samples are dissolved (1.0% wt. / wt.) in tetrahydrofuran (THF) containing 0.5% toluene as Flow rate marker. The analysis are performed by liquid chromatography (Agilent HPLC 1100) equipped with 6 varied pore-sized PLGel GPC columns (300 x 7.5mm x 5pm). The components of the sample are separated by the GPC columns based on their molecular size in solution and detected by a Refractive Index detector. The data are gathered and processed by Agilent's ChemStation GPC data analysis software.B) Viscosity

[0138] The viscosity of the various radiation curable compositions is measured at 60°C with a cone and plate type rheometer MCR102e (Anton Paar) according to test method ASTM D7867-13. A fixed shear rate of 20 s-1 is used.C) Mechanical properties

[0139] Elongation at break, tensile strength and Young’s modulus measurements are performed at 23°C according to test method ASTM D-882-18, and using a single column universal tensile testing machine (Instron's 4467 series). The test specimens used for the measurements are prepared according to the following procedure:The radiation curable composition comprising the oligomer is combined with 1.5 wt.% of a suitable photoinitiator (PI-TPO) and thoroughly mixed in a FlackTek SpeedMixer® at 900 rpm for 5 minute. The resulting material is applied as a 0. 127 mm thick film in a frame made of PET film and then covered by another PET film on top. The laminated PET sheet is cured by Fusion Aetek UV Hg lamp (2 x 400 W / inch power) at a speed of 50 fpm with 3 passes on each side. The laminated PET sheet is cut into strips having a length of 200 mm and a width of 12.7 mm. PET film on top and bottom is further removed to obtain UV cured free film testing. The overall thickness of UV cured free film is around 0.127 mm.Raw materials:

[0140] In the examples, the following raw materials and starting products are used:Isophorone diisocyanate is commercially available from Sigma-Aldrich. Referred to hereinafter as IPDI.Tetramethylxylylene diisocyanate is commercially available from Sigma-Aldrich. Referred to hereinafter as TMXDI.2-Hydroxyethyl acrylate is a compound comprising a hydroxyl group and an ethylenically unsaturated group, commercially available from Sigma-Aldrich. Referred to hereinafter as HEA.2-Hydroxyethyl methacrylate is a compound comprising a hydroxyl group and an ethylenically unsaturated group, commercially available from Sigma-Aldrich. Referred to hereinafter as HEMA.Poly(tetrahydrofuran) is a polyether polymeric diol having a number average molecular weight (Mn) of about 2000 g / mol, commercially available from Sigma-Aldrich. Referred to hereinafter as PTMEG.Tricyclodecane dimethanol is a non-polymeric cycloaliphatic diol, commercially available from TCI Chemicals. Referred to hereinafter as TCDM.4,4'-Methylenebis(cyclohexylamine) is a bicyclic aliphatic diamine, commercially available from Sigma-Aldrich. Referred to hereinafter as MBCH.4,4-Trimethylenedipiperidine is a bicyclic aliphatic diamine, commercially available from Sigma-Aldrich. Referred to hereinafter as TMDP.1.3-Bis (aminomethyl) cyclohexane is a monocyclic aliphatic diamine, commercially available from Sigma- Aldrich. Referred to hereinafter as BACH.Jeffamine® D-4000 is a is polyetherdiamine comprising repeating oxypropylene units in the backbone and having a number average molecular weight of 4000 g / mol. commercially available from Huntsman. Referred to hereinafter as D-4000.N-Vinyl methyl oxazolidinone is a radiation polymerizable monomer, commercially available from BASF under the trade designation VMOX®. Referred to hereinafter as VMOX.N-vinyl caprolactam is a radiation polymerizable monomer, commercially available from Sigma-Aldrich. Referred to hereinafter as NVCL.Isobornyl methacrylate is a radiation polymerizable cyclic acrylate monomer, known as a reactive diluent and commercially available from Allnex. Referred to hereinafter as IBOMA.Hydroxypropyl methacrylate is a radiation polymerizable acrylate monomer, known as a reactive diluent and commercially available from Sigma-Aldrich. Referred to hereinafter as HPMA.1.6-Hexanediol diacrylate is a radiation polymerizable linear acry late monomer, known as a reactive diluent and commercially available from Allnex. Referred to hereinafter as HDD A.Ebecryl®118 is a radiation polymerizable aromatic monofunctional acrylate monomer, known as a reactive diluent and commercially available from Allnex. Referred to hereinafter as E-l 18.Ebecryl®4859 is a radiation polymerizable urethane diacrylate oligomer, commercially available from Allnex. Referred to hereinafter as E-4859.2.4.6-Trimethylbenzoyldi-Phenylphosphinate is a photoinitiator, commercially available from Sigma-Aldrich. Referred to hereinafter as PI-TPO.Examples:Example 1: General procedure for the preparation of exemplary urethane-urea oligomers (P) using TMXDI as the diisocyanate (Ex.l to Ex.3) and comparative urethane-urea oligomer (Ex, Cl).

[0141] The diisocyanate compound (A) and conventional additives (stabilizers and catalysts) are charged into a reactor at 23°C and the mixture is then stirred for 30 minutes. The temperatureof the reactor is then set at 60°C and the compound (B) is then added dropwise under agitation over a period of one hour. After the addition of compound (B) has been completed, the reaction mixture is stirred for one more hour at 60°C. Then, the polymeric diol (DL) is added dropwise under agitation over a period of 30 minutes. After the addition of the polymeric diol (DL) has been completed, the reaction mixture is raised to 90°C and stirred for two more hours. The reaction mixture is then cooled to 80°C by the addition of the used reactive diluents (T). The diamine (DM) is then added into the reaction mixture. After the addition of the diamine (DM) has been completed, the reaction mixture is raised again to 90°C and stirred for two more hours. The obtained urethane-urea oligomers (P) are then transferred to a separate container for storage.urethane-ureausing IPDT as the diisocyanate (Ex.4 to Ex.6) andurethane oligomers (Ex.C2 and

[0142] The diisocyanate compound (A) and conventional additives (stabilizers and catalysts) are charged into a reactor at 23°C and the mixture is then stirred for 30 minutes. The temperature of the reactor is then set at 60°C and the compound (B) is then added dropwise under agitation over a period of one hour. After the addition of compound (B) has been completed, the reaction mixture is stirred for 30 more minutes at 60°C. Then, the polymeric diol (DL) is first dissolved in any one of the used reactive diluent (T) and then added dropwise under agitation over a period of 30 minutes. After the addition of the polymeric diol (DL) has been completed, the reaction mixture was maintained at 60°C and stirred for one more hour. The diamine (DM) is then added slowly into the reaction mixture, while maintaining the temperature of the reaction mixture below 75°C. After the addition of the diamine (DM) has been completed, the reaction mixture is maintained at 60°C and stirred for 30 more minutes. The obtained urethane-urea oligomers (P) are then transferred to a separate container for storage.

[0143] The comparative urethane oligomers (Ex,C2 and Ex,C3) are prepared in a manner similar as described above at the exception that no diamine is used. In Ex.C2, no additional diol is used, whereas in Ex.C3 a second non-polymeric diol is used in lieu of the diamine.radiation curableurethane- urea oligomers (Ex.l to Ex.6) and(Ex.Cl to Ex.C3).

[0144] The exemplary7radiation curable compositions comprising urethane-urea oligomers (Ex. l to Ex.6) and comparative compositions (Ex.Cl to Ex.C3) are prepared according to the procedure described hereinbefore. Comparative composition (Ex.Cl) comprises a urethaneurea oligomer, wherein the diamine used has a number average molecular weight of 4000 g / mol. Comparative compositions (Ex.C2 to Ex.C3) comprise urethane oligomers and not urethaneurea oligomers. The corresponding formulations are presented in Table 1 below.Table 1 : Formulation of exemplary radiation curable compositions comprising urethane-urea oligomers (Ex.l to Ex.6) and comparative compositions (Ex.Cl to Ex.C3).Example 4: Double bond content (DBC) and mechanical performance of exemplary radiation curable compositions comprising urethane-urea oligomers (Ex. 1 to Ex.6) and comparative compositions (Ex.Cl to Ex,C3).

[0145] The mechanical performance of exemplary radiation curable compositions comprising urethane-urea oligomers (Ex. l to Ex.6) and comparative compositions (Ex.Cl to Ex.C3) has been determined at 23°C according to the test method described hereinbefore. The results are presented in Table 2 below together with the double bond content (DBC) of the corresponding oligomers.Table 2: Double bond content (DBC) and mechanical performance of exemplary radiation curable compositions comprising urethane-urea oligomers (Ex. l to Ex.6) and comparative compositions (Ex.Cl to Ex.C3).

[0146] As can be seen from the results shown in Table 2, the radiation curable compositions according to the present disclosure (Ex. 1 to Ex.6) are provided with excellent balance of mechanical properties. In contrast, the composition of the comparative examples Ex. Cl to Ex.C3 are less advantageous. Tn particular, the comparative compositions are typically deficient in terms of tensile strength and Young’s modulus. Moreover, the composition of the comparative examples Ex.Cl and Ex.C2 are particularly disadvantageous due in particular to their DBC value no greater than 0.45 mol / kg.Example 5: Three-dimensional printability performance of exemplary radiation curable compositions comprising urethane-urea oligomers (Ex. l to Ex, 3).

[0147] The three-dimensional pnntability performance of exemplary radiation curable composition comprising urethane-urea oligomers (Ex. l to Ex.3) has been determined by printing spur gear and internal spur gear designed parts using a Asiga Max printer (385 nm) with a layer thickness of 50 micrometers at 25°C. Other printing parameters included: 7.5 seconds of irradiation (10.2 mW) for the base layer and 6 seconds of irradiation (9.9 mW) for all other layers. The green parts were sonicated in an isopropyl alcohol (IPA) bath at 23°C for 5 minutes, dried in an oven at 60°C for 20 minutes, followed by 2 minutes of post UV curing for each side of the part.

[0148] The radiation curable composition according to the present disclosure (Ex. l to Ex.3) were found to be associated with excellent three-dimensional printability characteristics. The spur gear and internal spur gear designed parts resulting from the three-dimensional printing were found to have excellent resolution and surface finish properties. The three-dimensional printed parts were also found to have excellent physical properties, including impact resistance, thermal properties (in particular heat deflection) and shore hardness.

Claims

CLAIMS1. A radiation curable composition comprising at least one urethane-urea oligomer (P) obtained from the reaction of: a) at least one diisocyanate compound (A); b) at least one compound (B) comprising at least one hydroxyl group and further comprising at least one ethylenically unsaturated group; c) at least one polymeric diol (DL); and d) at least one diamine (DM) having a number average molecular weight (Mn) of less than 4000 g / mol; wherein the urethane-urea oligomer (P) comprises at least two urea linkages obtained from the reaction between the at least one diisocyanate compound (A) and the at least one diamine (DM), wherein the urethane-urea oligomer (P) further comprises at least two urethane linkages obtained from the reaction between the at least one diisocyanate compound (A) and the at least one hydroxyl group of the least one compound (B), and wherein the ethylenically unsaturated groups are located in the terminal positions of the urethane-urea oligomer (P).

2. A radiation curable composition according to claim 1, wherein the at least one diamine (DM) has a number average molecular weight (Mn) of less than 3000 g / mol, less than 2500 g / mol, less than 2000 g / mol, less than 1000 g / mol, less than 500 g / mol, less than 400 g / mol, less than 300 g / mol, less than 250 g / mol, less than 200 g / mol, or even less than 150 g / mol.

3. A radiation curable composition according to any one of claim 1 or 2, wherein the at least two urea linkages of the at least one urethane-urea oligomer (P) are each separated from the at least one ethylenically unsaturated group by at least one urethane linkage obtained from the reaction between the at least one diisocyanate compound (A) and the at least one hydroxyl group of the least one compound (B).

4. A radiation curable composition according to any one of the preceding claims, wherein the urethane-urea oligomer (P) further comprises at least two additional urethanelinkages obtained from the reaction between the at least one diisocyanate compound (A) and the at least one polymeric diol (DL).

5. A radiation curable composition according to any one of the preceding claims, wherein the urethane-urea oligomer (P) is represented by the following formula (I) :Compound (B) - {diisocyanate compound (A) - polymeric diol (DL)}m- {diisocyanate compound (A) - diamine (DM)}n- diisocyanate compound (A) - Compound B(I) wherein: m and n are integers independently selected from 1 to 5, or even from 1 to 3.

6. A radiation curable composition according to any one of the preceding claims, wherein the urethane-urea oligomer (P) is represented by the following formula (III): fK]-O(O)C{-N(H)-[E]-N(H)-C(O)O-[G]-O(O)C}m {-N(H)-[E]-N(H)-C(O)-N(H)-[J]-N(H)-C(O)}n -N(H)-[E]- N(H) -C(O)O-[K](III) wherein:K is the residue of compound (B);E is the residue of the diisocyanate compound (A);G is the residue of the polymeric diol (DL);J is the residue of the diamine (DM); and m and n are integers independently selected from 1 to 5, or even from 1 to 3.

7. A radiation curable composition according to any one of the preceding claims, wherein the at least one ethylenically unsaturated group of at least one compound (B) is selected from the group consisting of (meth)acryloyl, (meth)acrylamide, vinyl, vinylether, allyl, styrenyl, methylstyrenyl, maleyl , fumaryl functional groups, and any combinations or mixtures thereof.

8. A radiation curable composition according to any one of the preceding claims, wherein the at least one polymeric diol (DL) is selected from the group consisting of polyether diols, polyester diols, in particular polycaprolactone diols, polybutadiene diols,polycarbonate diols, polyacrylate diols, polyacrylic diols, and any combinations or mixtures thereof.

9. A radiation curable composition according to any one of the preceding claims, wherein the at least one diamine (DM) is selected from the group consisting of aliphatic diamines, cycloaliphatic diamines, aromatic diamines, polyether diamines, and any combinations or mixtures thereof.

10. A radiation curable composition according to any one of the preceding claims, which comprises: a) from 20 to 80 wt.%, from 30 to 80 wt.%, from 40 to 80 wt.%, from 40 to 75 wt.%, from 45 to 75 wt.%, from 50 to 75 wt.%, from 50 to 70 wt.%, from 55 to 70 wt.%, or even from 55 to 65 wt.%, of the urethane-urea oligomer (P); b) from 20 to 60 wt.%, from 30 to 60 wt.%, from 30 to 55 wt.%, from 35 to 55 wt.%, from 35 to 50 wt.%, or even from 35 to 45 wt.%, of a reactive diluent (T); and c) optionally, from 0 to 5 wt.%, from 0.5 to 5 wt.%, or even from 1 to 5 wt.%, of a radiation sensitive polymerization initiator; wherein the wt.% are based on the total weight of the radiation curable composition.

11. A process for the manufacturing of a radiation curable composition according to any one of the preceding claims, wherein the process comprises the steps of: a) bringing the at least one diisocyanate compound (A) in presence of the at least one compound (B), the at least one polymeric diol (DL) and the at least one diamine (DM), thereby forming a mixture material comprising the at least one urethane-urea oligomer (P); b) optionally, subjecting the mixture material to thermal energy; and c) optionally, subjecting the mixture material to mechanical mixing.

12. A process of making a cured polymeric material, comprising the steps of: a) providing a radiation curable composition according to any one of claims 1 to 10; and b) exposing the radiation curable composition to actinic radiation.

13. A cured polymeric material produced by a process according to claim 12, which has an elongation at break value greater than 50 %, greater than 80 %, greater than 100 %, greater than 120 %, greater than 140 %, greater than 160 %, greater than 180 %, greater than 200 %, greater than 220 %, greater than 250 %, greater than 260 %, greater than 280 %, or even greater than 300 %, when measured according to the test method described in the experimental section.

14. A cured polymeric material according to claim 13, which has a tensile strength value greater than 5 MPa, greater than 10 MPa, greater than 15 MPa, greater than 18 MPa, greater than 20 MPa, greater than 22 MPa, greater than 25 MPa, greater than 28 MPa, greater than 30 MPa, greater than 32 MPa, greater than 34 MPa, greater than 36 MPa, greater than 38 MPa, or even greater than 40 MPa, when measured according to the test method described in the experimental section.

15. Use of a radiation curable composition according to any one of claims 1 to 10 in a three- dimensional printing process, in particular in a three-dimensional printing process using vat (photo)polymerization techniques.

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