resin composition

Abstract

1. A resin composition for 3D printing of objects, comprising: a photocurable component A serving as a 3D structurable matrix; a component B serving as a synergistic combination of flame retardants; and at least one photoinitiator suitable for polymerization by light excitation, wherein, based on the total weight of components A and B, the amount of curable component A is in the range of 60% to 95% by weight, preferably 65% ​​to 90% by weight, and more preferably 70% to 85% by weight; the amount of flame retardant component B is in the range of 5% to 40% by weight, preferably 10% to 35% by weight, and more preferably 15% to 30% by weight, based on the total weight of components A and B; and the amount of photoinitiator is in the range of 0.01% to 10% by weight, based on the weight of component A alone.

Description

[Technical Field]

[0001] The present invention relates to a resin composition for 3D printing of objects having flame retardant properties and good (thermo)mechanical properties. Furthermore, the present invention relates to a method for producing an object by 3D printing from the resin composition of the present invention, and to an object produced from the resin composition of the present invention. [Background technology]

[0002] <Introduction> As 3D printing becomes more industrialized, the use and availability of flame-retardant 3D printing materials is becoming increasingly important. In particular, for lithography-based 3D printing processes and lithography-based additive manufacturing technologies (L-AMT), the availability of such flame-retardant materials remains very limited. This is because these technologies are characterized by high precision and manufacturing accuracy, especially in the micrometer range, which is crucial for the production of parts with wall thicknesses of less than 4 mm. Therefore, the materials used must maintain their flame-retardant effectiveness even at thin wall thicknesses, which is not yet possible with currently available material solutions on the market.

[0003] Photocurable materials (resins or formulations) for L-AMT typically consist of reactive components (e.g., monomers, oligomers, and photoinitiators) that polymerize and harden upon exposure to light, along with specific additives (e.g., fillers or process additives) that further adjust the overall performance of the material. Typically, photoinitiators are activated via light exposure to generate reactive sites (e.g., radicals, cations, and anions), which can then react with the respective reactive components (e.g., (meth)acrylates, (meth)acrylamides, vinyl esters, vinyl ethers, vinyl amides, N-vinyl compounds, vinyl carbonates, vinyl carbamates, maleimides, itaconates, fumarates, styrene compounds, epoxy compounds, or cyclic ethers such as oxetanes, benzoxazines, oxazolines, and cyanoacrylates) to form hardened materials.

[0004] (Meth)acrylate resins for lithography-based 3D printing have traditionally had poor fire resistance, which has severely limited their use as materials in industrial sectors such as the mobility sector (e.g., automotive, railway systems, aerospace) and the electronics industry, critically limiting their use in industrial components, household appliances, LED lighting technology, consumer and household appliances, power tools, connectors, switches, plugs, PC fans, structural and housing components, smartphones, washing machines, and aircraft parts.

[0005] Several technical solutions for improving flame retardancy in the L-AMT field are already known.

[0006] WO 2020 / 055682 (Carbon, Inc.) discloses dual-cure resin compositions for producing flame-retardant 3D parts using stereolithography (SLA) (e.g., continuous liquid interface manufacturing). WO 2019 / 130306 (Bromine Compounds LTD.) discloses flame-retardant photocurable formulations, and WO 2013 / 189821 (Allnex) discloses flame-retardant radiation-curable compositions. These referenced flame-retardant materials are composed of halogenated resin components.

[0007] Furthermore, Chinese Patent Application Publication No. 112940189 discloses a flame-retardant photosensitive resin composition and its manufacturing and use methods. The flame-retardant photosensitive resin composition contains, by weight, 20-50 parts of a photosensitive resin, 20-50 parts of a reactive diluent, 5-15 parts of a flame retardant, 1-5 parts of a photoinitiator, and 0.1-2.0 parts of other additives, and the flame retardant includes a combination of a phenylphosphorus flame retardant and a brominated alkyl flame retardant. Therefore, the flame-retardant material is composed of a halogenated resin component.

[0008] Flame retardants are increasingly attracting scientific and public attention. The debate over flame retardants began in the early 1990s, when several brominated flame retardants (BFRs) became environmental hot topics. Some BFRs were found to have the potential to produce halogenated dioxins and furans under severe heat stress, accidental fires, or uncontrolled combustion. Further knowledge about the environment and biota, as well as suspicions that some BFRs may bioaccumulate, have further deepened these concerns. Meanwhile, the environmental and health properties of BFRs as well as other types of flame retardants are being extensively studied to determine which flame retardants, regardless of their chemical nature, could be effective alternatives in terms of efficacy and environmental impact.

[0009] Sustainable and environmentally friendly alternatives to halogen-based flame retardants typically include inorganic flame retardants (e.g., aluminum hydroxide, magnesium hydroxide, calcium hydroxide, antimony oxide, tin oxide, borax, expandable graphite, zinc borate), phosphorus-based flame retardants (e.g., organic phosphates, inorganic phosphates, phosphonates and phosphinates, and red phosphorus), or nitrogen-based flame retardants (e.g., melamine and melamine derivatives (melamine cyanurate, melamine phosphate, melem, melon, etc.)).

[0010] Chinese Patent Application Publication No. 105068378 discloses a flame-retardant photosensitive SLA resin for 3D printing. The disclosed photosensitive resin is composed of the following components (by weight): 15-75% phosphorus-containing acrylate prepolymer, 15-75% acrylate, 1-5% free radical initiator, 0.5-2% adjuvant, and 5-15% reactive diluent, with the total weight percentage of the above components being 100%. The disclosed photosensitive phosphorus-containing acrylate prepolymer has a flame-retardant effect, and adding a relatively large amount of this prepolymer can achieve better flame retardancy.

[0011] Chinese Patent Application Publication No. 102827332 discloses a UV-curable, transparent, halogen-free, flame-retardant unsaturated polyester and its manufacturing method. The disclosed unsaturated polyester is defined by weight percentage, and the raw material composition is 49.5%-65% unsaturated phosphorus-boron-based flame-retardant polyester prepolymer, 50%-30% reactive diluent, 0.4%-4.5% photoinitiator, and 0.1%-0.5% polymerization inhibitor. The unsaturated phosphorus-containing flame-retardant polyester prepolymer is obtained by reacting glycol with an unsaturated dibasic acid anhydride and / or unsaturated dibasic carboxylic acid, a phosphaphenanthrene anhydride derivative, and boric acid at 150-205°C. The disclosed unsaturated polyester exhibits a volatile loss rate of less than 1% during the curing process, and is therefore considered to have advantages such as low volatile loss, halogen-free flame retardancy, and transparency. However, the flame retardant content in the disclosed unsaturated polyester is relatively high, which places relatively high demands on the manufacturing process.

[0012] Korean Patent Application Publication No. 20210104367 discloses a flame-retardant composition for post-coating digitally printed materials such as photoprints. This composite flame retardant contains an inorganic phosphorus-based flame retardant, such as red phosphorus, ammonium phosphate, or ammonium polyphosphate, and an organic phosphorus-based flame retardant, such as an aromatic phosphate or haloalkyl phosphate. Korean Patent Application Publication No. 20210104367 emphasizes the importance of using the composite flame retardant in a weight ratio of inorganic phosphorus-based flame retardant to organic phosphorus-based flame retardant of 1:0.1-10, particularly 1:0.5-5. Korean Patent Application Publication No. 20210104367 notes that a weight ratio of less than 1:0.1 reduces the homogeneity, adhesion, and flexibility of the flame-retardant layer of the coating, potentially leading to cracking and peeling due to harmful external influences such as wind and rain. If the weight ratio exceeds 1:10, the flame retardancy of the coating according to Korean Patent Application Publication No. 20210104367 is improved, but there is a concern that the flame retardancy may not be sufficient.

[0013] In CN113637118, phosphinates and polyphosphates are blended into photopolymer resins in amounts of approximately 10-40% by weight of the total resin. This results in a photosensitive 3D printing resin that is high-temperature resistant, halogen-free, and flame-retardant. However, CN113637118 does not discuss synergistic blend ratios or advantageous flame retardant combinations in terms of combining flame retardancy and (thermo)mechanical performance, nor does it discuss the properties and design of the flame retardant additives or the resin matrix.

[0014] The processing of photocurable formulations into 3D objects can be accomplished via a variety of additive manufacturing (L-AMT) technologies, including, but not limited to, stereolithography (SLA), digital light processing (DLP), digital inkjet printing, hot lithography, continuous liquid interface modeling (CLIP), large-area rapid printing (HARP), multi-jet modeling, two-photon photopolymerization (TPP), or other liquid additive manufacturing technologies. These technologies are primarily based on building up the final 3D object layer by layer and can be realized in various forms, including bottom-up or top-down, in a continuous manner, and / or using moving digital light processing (DLP) or laser-type systems for larger printing areas. Current resin formulations applied to these technologies almost exclusively have low viscosities (<1 Pa·s, measured according to DIN EN ISO 2884-1, DIN EN ISO 2884-2, or according to the procedures described herein), which are essential for the success of the build-up job or step, ensuring high feature resolution and preventing processing defects.

[0015] The Applicant has developed a hot lithography process (EP 3284583) that allows for lithography-based 3D structuring at elevated temperatures of photocurable resins that have a high viscosity at ambient temperature (20°C), typically above 1 Pa·s. In the context of EP 3284583, high viscosity is observed when processing photocurable resins that contain a high content of monomers, oligomers, and / or prepolymers characterized by: a high molecular weight of more than 500 g / mol, preferably more than 2000 g / mol; and / or a high melting point or high softening temperature (above 35°C); and / or strong intermolecular forces (e.g., urethanes, ureas, carbonates, esters, amides); and / or a high content of fillers (e.g., ceramic, metal, and / or polymer particles and / or fibers) that are added to the photocurable resin to optimize the performance of the final cured material. The combination of high temperature and processing of high viscosity resin formulations allows for the 3D structuring of light-curable materials that are flame-resistant, tough, heat-resistant and impact-resistant.

[0016] In recent years, intense attention has focused on hybrid resin systems composed of one or more additional material components different from those used in the photopolymer network formation via the photostructuring step of L-AMT. Such promising hybrid material concepts show great potential for the creation of tough photopolymer resins for additive manufacturing, resulting in photopolymerized materials that simultaneously possess high toughness and heat resistance. Hybrid resin systems can be defined as resin materials that undergo various curing steps triggered by different impulses (e.g., a photocuring step followed by a thermal curing step, as in EP 4049841 or U.S. 2016 / 0160077) and / or materials that exhibit multiple curing mechanisms (e.g., a curing mechanism that combines radical and cationic curing mechanisms, or various radical curing mechanisms triggered by subsequent processes, as in WO 2016 / 200972 or WO 2018 / 191247). The photopolymer network thus formed is considered a hybrid material composed of a first component and a second component, or multiple additional components, and typically represents a full interpenetrating network (IPN), semi-IPN, pseudo-IPN, dual network, or polymer blend. To maintain light reactivity and ensure processability in L-AMT, the resin must be formulated with an effective content of the photocurable component to obtain a material with sufficient green strength. Green strength is the mechanical strength (e.g., measured by a tensile test according to DIN EN ISO 527 or a flexural test according to DIN EN ISO 178) of a material that has undergone only the photocurable additive manufacturing step before undergoing the additional thermal curable additive manufacturing step.

[0017] Materials formed from such hybrid resins through a first photo-curing step and a second or multiple additional curing steps different from the first photo-curing step, via different curing mechanisms, offer a powerful design strategy for high-performance photopolymers that simultaneously possess high toughness and heat resistance, and are also a promising concept for designing flame-resistant photopolymers. The second or multiple additional curing steps can be performed simultaneously with or subsequent to the initial photo-curing step (e.g., the structuring step in L-AMT). Examples of the second or multiple additional curing steps include the following steps: i) a thermal curing step that causes thermal curing of the resin portion that has not been cured via the first light curing step (e.g., thermal curing of an epoxy thermoset resin in an acrylate matrix); ii) a curing step catalyzed by moisture or an organic catalyst, which causes the uncured resin portions to harden via a first light-curing step (e.g., curing of resins with free isocyanate or silane groups), and / or a curing step which first causes the decomposition of the resin portions and then causes the uncured resin portions to harden via a first light-curing step (e.g., curing and / or deblocking of resins with blocked isocyanate groups); iii) a photo-curing step that induces a different curing mechanism than the first photo-curing step and initiates curing of the resin portions that were not cured via the first photo-curing step (e.g., acrylate / epoxy resin systems that cure via radical and cationic polymerization); iv) A photo-curing step triggered by a different wavelength than the first photo-curing step and which initiates curing of resin portions that have not yet been cured through the first photo-curing step (e.g., acrylate resin portions that cure at wavelengths greater than 390 nm and epoxy resin portions that cure at wavelengths less than 380 nm).

[0018] In summary, it is considered very important to develop flame-retardant photopolymers that can achieve good flame retardancy with relatively small amounts of flame retardant while enabling an efficient and stable 3D printing manufacturing process. Furthermore, the final (thermo)mechanical material parameters of the resulting products must also be considered. Summary of the Invention

[0019] To achieve this object, the present invention provides a resin composition for 3D printing of objects with high flame resistance, the resin composition comprising: a) a curable component A, which comprises one or more photocurable components selected from Group I consisting of (meth)acrylates, meth)acrylamides, vinyl esters, vinyl ethers, vinylamides, N-vinyl compounds, vinyl carbonates, vinyl carbamates, maleimides, itaconates, fumarates, styrene compounds, cyclic ethers such as epoxy compounds or oxetanes, benzoxazines, oxazolines, and cyanoacrylates, wherein the one or more photocurable components selected from Group I form a first polymerized network; and b) a flame retardant component B, which is a combination of i) at least one of a nitrogen donor and a polyphosphate and a polyphosphonate, and ii) one or more inorganic phosphinate salts, wherein the weight ratio of i) to ii) is preferably 1 / 9 to 9 / 1; c) at least one photoinitiator, said at least one photoinitiator being suitable for polymerization by photoexcitation; Including, The amount of curable component A is in the range of 60% to 95% by weight, preferably 65% ​​to 90% by weight, more preferably 70% to 85% by weight, based on the total weight of components A and B; the amount of flame retardant component B is in the range of 5% to 40% by weight, preferably 10% to 35% by weight, more preferably 15% to 30% by weight, based on the total weight of components A and B; and the amount of photoinitiator is in the range of 0.01% to 10% by weight, based on the weight of component A alone.

[0020] Thus, the core of the present invention relates to a resin composition for 3D printing of articles with flame retardant properties and improved (thermo)mechanical properties, in which an advantageous combination of inorganic and organic flame retardant additives with phosphorus and / or nitrogen content is used in solid and / or liquid form, enabling both processability of the resin composition in a 3D printer (potentially with targeted filler design including fillers with particle sizes D50 values ​​in the range of 0.1-100 μm and / or liquid oligomers to reduce the "softening effect") and optimized (thermo)mechanical performance (e.g., a minimum required flame retardant content in the range of 5-40 wt. %, based on the total weight of curable component A and flame retardant component B). According to the present invention, a flame-retardant formulation of photocurable resins optimized for lithography-based 3D printing processes has been found, which allows the design and fabrication of flame-retardant materials with wall thicknesses of less than 4 mm, even less than 1.5 mm, while at the same time improving (thermo)mechanical properties compared to available flame-retardant photopolymer materials (e.g., T g >90°C, and this glass transition temperature T g (Elongation at break is typically derived from the maximum of the loss factor plot (tan δ) via dynamic mechanical analysis (DMA) and is >3% elongation at break). The formulations of the present invention are comprised of halogen-free materials, particularly halogen-free flame retardant materials, which are important for achieving sustainable and environmentally safe flame retardant resin formulations and products. [Brief explanation of the drawings]

[0021] [Figure 1] 1 shows the viscosity-temperature behavior of Comparative Examples CE1 to CE4 and Examples E1 to E4. [Figure 2] The stress-strain behavior of Comparative Examples CE1 to CE4 and Examples E1 to E4 is shown. [Figure 3] 1 shows the thermo-mechanical behavior (loss factor tan δ plot versus temperature) of Comparative Examples CE1 to CE4 and Examples E1 to E4. [Figure 4] 1 shows the thermo-mechanical behavior (storage modulus G' plot versus temperature) of Comparative Examples CE1 to CE4 and Examples E1 to E4. DETAILED DESCRIPTION OF THE INVENTION

[0022] According to a preferred embodiment of the present invention, component A further comprises one or more thermosetting components selected from group II consisting of monofunctional or polyfunctional components, T g forming a second polymerized network having a T >100°C; g The component functions as a TGE (thermal growth enhancer). In Component A, the amount of one or more components from Group II is 1 to 50 wt%, preferably 2 to 40 wt%, more preferably 3 to 30 wt%, and even more preferably 5 to 25 wt%, based on the total weight of the components from Group I and Group II. The amount of one or more components from Group I is 50 to 99 wt%. By introducing such components from Group II, a hybrid resin is introduced via a different curing mechanism, through a first photocuring step (Group I) and a second or multiple additional curing steps (Group II) different from the first photocuring step. This results in a high-performance photopolymer that simultaneously possesses high toughness and heat resistance.

[0023] In the context of this application, the temperature T g is the glass transition temperature derived via DMA, typically from the maximum of the tan δ plot of a network formed from only this component or combination of these components, without other networks, polymer backbones, or sub-networks, the tan δ plot being recorded according to the DMA method described herein.

[0024] Preferably, component A consists of one or more components selected from group I and, optionally, one or more components selected from group II, i.e., component A contains only components selected from group I and group II.

[0025] In a preferred embodiment of the present invention, the component selected from group I is Subgroup i) one or more monofunctional photocurable components, also called reactive diluents (RD), having the formula (I): XY Formula (I) and comprising a reactive species Y and pendant groups X susceptible to radical or cationic polymerization, wherein the one or more components of subgroup i) form a polymer backbone upon photoinduced curing, and the backbone preferably has a T above 25°C. g the one or more monofunctional photocurable components having Subgroup ii) one or more mono- or polyfunctional photocurable components, which copolymerize with said one or more components of subgroup i) via a curing mechanism, preferably have a molecular weight greater than 500 g / mol, function as toughness modifiers (TNMs), and preferably have an elongation at break greater than 10% and a T of greater than 0°C. g the one or more mono- or polyfunctional photocurable components forming a polymeric network having Optionally, Subgroup iii) one or more photocurable cross-linking components, referred to as cross-linking agents (CA), which copolymerize with said one or more components of subgroup i) and subgroup ii) via a curing mechanism; It consists of a combination of:

[0026] In the context of this application, the term "polymer backbone" defines the molecules forming the non-crosslinked polymer resulting from the polymerization of the monofunctional components of subgroup i). The polymer backbone represents a subgroup of the first polymer network of the present invention. Other monomers or oligomers may be (co)polymerized with such a polymer backbone. Furthermore, the polymer network formed by the components of subgroup ii) represents a sub-network of the first polymer network of the present invention. Furthermore, in the context of this application, the temperature T g is the glass transition temperature, typically derived via DMA, from the maximum of the tan δ plot of a network formed from only this component or combination of these components, without other networks, polymer backbones, or sub-networks, the tan δ plot being recorded according to the DMA method described herein.

[0027] In a preferred embodiment of the present invention, the amount of one or more components of subgroup i) is in the range of 5% to 60% by weight, the amount of one or more components of subgroup ii) is in the range of 5% to 95% by weight, and the amount of one or more components of subgroup iii) is in the range of 5% to 95% by weight, based on the total weight of the components of subgroup i), subgroup ii) and subgroup iii).

[0028] In a preferred embodiment, component A comprises reactive diluents as subgroup i) represented by components of formula (I), wherein: - Y is a chemical species selected from the group of (meth)acrylates, (meth)acrylamides, vinyl esters, vinyl ethers, vinyl amides, N-vinyl compounds, vinyl carbonates, vinyl carbamates, maleimides, itaconates, fumarates or styrene compounds, and derivatives thereof, optionally substituted with one or more of C1-C6 alkyl, C1-C6 alkoxy, C1-C6 thioether, halogen, -NO2, -SO2H, -CF2, -OH, -NH2, -SH, -CN, -trimethoxysilyl or triethoxysilyl; X is one or more linear, branched or cyclic, bicyclic or polycyclic C5-C alkyl radicals selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl, hexyl, 2-ethylhexyl, octyl, decanyl, dodecanyl, acetic acid, propanoic acid, butanoic acid, pentanoic acid, undecanoic acid, dodecanoic acid, benzoic acid and the corresponding esters, alkyl esters or aromatic esters, phenyl, benzyl, phenethyl, biphenyl, naphthyl, anthracenyl, pyrenyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, 4-isobutylcyclohexyl, cycloheptyl, cyclooctyl, adamantyl, isobornyl, salicyl, and cholesteryl. 40 represents an aliphatic, heterocyclic or aromatic residue, one or more of which groups may be individually bonded via an ester, amide, urea, urethane, carbonate, ether or thioether group, and these groups may be C1-C6 alkyl, C1-C6 alkoxy, C3-C7 cycloalkyl, C6-C 10-aryl, C1-C6-thioether, halogen, -NO2, -SO3H, -CF3, -OH, -NH2, -SH, -CN, -trimethoxysilyl, or triethoxysilyl.

[0029] Some preferred examples of reactive diluents as subgroup i) within component A include, but are not limited to, monofunctional (meth)acrylates, (meth)acrylamides, vinyl esters, and N-vinyl compounds, such as isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, trimethylcyclohexyl (meth)acrylate, glycerol formal (meth)acrylate, tricyclodecane methanol mono(meth)acrylate, 4-tert-butylcyclohexyl (meth)acrylate, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, cyclotrimethylolpropane formal (meth)acrylate, salicylate (meth)acrylate, such as 2-(methacryloyloxy)benzoic acid cyclopentyl ester, 2-(methacryloyloxy)benzoic acid cyclohexyl ester, 2-(methacryloyloxy)benzoic acid cyclohexyl ester, and the like. 2-(methacryloyloxy)benzoic acid-2-isopropyl-5-methylcyclohexyl ester, 3-(methacryloyloxy)benzoic acid-2-isopropyl-5-methylcyclohexyl ester, 4-(methacryloyloxy)benzoic acid-2-isopropyl-5-methylcyclohexyl ester, 2-(methacryloyloxy)benzoic acid-3,3,5-trimethylcyclohexyl ester, 2-(acryloyloxy)benzoic acid-3,3 ,5-trimethylcyclohexyl ester, 2-(methacryloyloxy)benzoic acid decahydronaphthalen-2-yl ester, 2-(methacryloyloxy)benzoic acid-1,3,3-trimethyl-2-bicyclo[2.2.1]heptanyl ester, 2-(methacryloyloxy)benzoic acid-1,7,7-trimethyl-2-bicyclo[2.2.1]heptanyl ester, 2-(methacryloyloxy)benzoic acid-bicyclo[2.2.1]Heptan-2-ylmethyl ester, 2-(methacryloyloxy)benzoic acid-2-cyclohexylethyl ester, 2-(methacryloyloxy)benzoic acid benzyl ester, 4-(methacryloyloxy)benzoic acid benzoate, 3-(methacryloyloxy)benzoic acid-4-isopropylbenzyl ester, 2-(acryloyloxy)benzoic acid benzyl ester, 2-(methacryloyloxy)benzoic acid phenethyl ester, 4-(methacryloyloxy)-3-methoxybenzoic acid-3-methoxybenzyl ester, 2-(methacryloyloxy)benzoic acid-1-phenethyl ester Examples of suitable acrylates include 4-((methacryloyloxy)methyl)benzoic acid cycloheptyl ester and 2-(methacryloyloxy)benzoic acid cyclohexylmethyl ester, cholesteryl (meth)acrylate, biphenyl (meth)acrylate, phenylacrylamide, diacetone acrylamide, t-butylacrylamide, N-acryloylmorpholine, N-vinylpyrrolidone, N-vinylcaprolactam, N-vinylformamide, vinyl cinnamate, vinylmethyloxazolidinone, and 2-(allyloxymethyl)acrylic acid methyl ester.

[0030] In a preferred embodiment, component A comprises, as subgroup ii), mono- or polyfunctional photocurable derivatives as toughness modifiers (TNM), which are copolymerized with the other components of component A via the corresponding curing mechanism and have a number average molecular weight of more than 500 g / mol, preferably more than 1000 g / mol, and are selected from the group consisting of (meth)acrylates, (meth)acrylamides, vinyl esters, vinyl ethers, vinylamides, N-vinyl compounds, vinyl carbonates, vinyl carbamates, maleimides, and optionally the toughness modifier is at least one of a (poly)ether, a (poly)ester, a (poly)carbonate, a (poly)urethane, a (poly)siloxane, a (poly)amide, a (poly)isoprene, a modified epoxy-functionalized oligomer, and optionally a C1-C6 alkyl, a C1-C6 alkoxy, a C3-C7 cycloalkyl, a C6-C7 alkyl ester ... 10and are substituted with one or more of aryl, C1-C6 thioether, halogen, —NO2, —SO3H, —CF3, —OH, —NH2, —SH, —CN, -trimethoxysilyl, and -triethoxysilyl, and preferably form polymeric networks with elongation at break greater than 10%, preferably greater than 20%, where again, the elongation at break is measured on the pure polymeric network formed by these materials, in the absence of other polymers such as polymer backbones or other sub-networks.

[0031] Preferred TNMs as subgroup ii) within component A are multifunctional oligomers, prepolymers and / or polymers with an average reactive group functionality greater than 1.3, preferably greater than 1.5, more preferably greater than 1.9, or an average reactive group functionality of 0.9 to 2.1, or 0.9 to 3.1, or 2.9 to 3.1, or 1.9 to 2.1. A reactive group in this context is a functional group that is susceptible to polymerization.

[0032] Some preferred examples of TNM in component A include di- or polyfunctional (meth)acrylates, such as ethoxylated bisphenol A di(meth)acrylates (e.g., Miramer 2200, Miramer 2301), aliphatic urethane di(meth)acrylates (e.g., Ebecryl 8811, Ebecryl 8809, Ebecryl 8409, Ebecryl 246, Miramer PU2100, Miramer SC2404, Miramer SC2565, Miramer PU2564, BR-571 MB, BR-7432GB, CN9001, CN965, CN981, CN8881 NS), polyether urethane (meth)acrylates (e.g., BR-541 MB, BR-582H15), hydrophobic urethane (meth)acrylates (e.g., BRC-443D already contains 5-15% of component A as a reactive diluent (RD)), polyester urethane (meth)acrylates (e.g., BR-744 BT), polyester di(meth)acrylates (e.g., CN2608A, CN704, CN790, Ebecryl4766), modified epoxy di(meth)acrylates (e.g., CN2003EU), and oligomeric polycarbonate di(meth)acrylates.

[0033] In another preferred embodiment, such TNMs may also be combined with and / or comprise multiple urethane, ester and / or carbonate moieties.

[0034] Some preferred examples of the crosslinking agent (CA) in component A include at least one difunctional and / or multifunctional (meth)acrylate, or a mixture of difunctional and / or multifunctional (meth)acrylates. These CAs are composed of one or more polymerizable oligomers, i.e., oligomers that can be polymerized by light, and are therefore particularly preferred as part of the photocurable component matrix. The multifunctional monomers that make up the CA in component A may be polymerized via a radical mechanism. Examples of such multifunctional monomers include trifunctional, tetrafunctional, pentafunctional, and / or hexafunctional (meth)acrylates, and / or hyperbranched and / or dendritic (meth)acrylates with more functional groups. These are known for their fast reaction rate and high crosslink density, as well as improved heat resistance (e.g., higher T g ) is suitable for this reason.

[0035] Some preferred CA compounds in component A of the resin composition of the present invention include multifunctional (meth)acrylates and / or mixtures of multifunctional (meth)acrylates, which enhance the green strength of 3D printed parts and support the 3D structuring of complex thin-walled structures. The crosslinking components, unlike the TNMs in component A, have low molecular weights (<500 g / mol) or high reactive group functionality (>2), which in both cases results in high crosslink density and thus overall high green strength. A reactive group in this context is a functional group that is susceptible to polymerization.

[0036] Such crosslinking agents (CA) in component A preferably include 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate or 1,12-dodecanediol di(meth)acrylate, 1,6-bis-[2-(meth)-acryloyloxyethoxycarbonylamino]-2,2,4-trimethylhexane, pentaerythritol tetra(meth)acrylate, di-, tri-, or tetra-ethylene glycol-di(meth)acrylate, and trimethylolpropane tri(meth)acrylate.

[0037] Additionally, preferred CAs in component A are comprised of rigid groups such as aromatic or alicyclic groups because of their low tendency to polymerization shrinkage, high green strength, and high heat resistance of the cured resin. Some preferred CAs within component A include 2-(2-biphenyloxy)-ethyl(meth)acrylate, bisphenol A-di(meth)acrylate (an addition product of (meth)acrylic acid and bisphenol A-diglycidyl ether), ethoxylated or propoxylated bisphenol A-di(meth)acrylate (e.g., 2-[4-(2-(meth)acryloyloxyethoxyethoxy)phenyl]-2-[4-(2-(meth)acryloyloxyethoxy)phenyl]-propane) or 2,2-bis[4-(2-(meth)acryloyloxypropoxy)phenyl]propane, tricyclodecane dimethanol di(meth)acrylate, isophorone urethane di(meth)acrylate, or tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate.

[0038] According to the present invention, the flame retardant component B is a combination of i) at least one of a nitrogen donor and a polyphosphate and a polyphosphonate, and ii) one or more inorganic phosphinate salts, wherein the weight ratio of i) to ii) is preferably from 1 / 9 to 9 / 1.

[0039] In a preferred embodiment, Component B is formulated to provide high flame resistance and processability with L-AMT. This preferred combination is achieved when, in Component B, the amount of at least one of the nitrogen donor, polyphosphate, and polyphosphonate is in the range of 20% to 80% by weight, preferably 20% to 55% by weight, based on the total weight of Component B, and the amount of one or more inorganic phosphinate salts is in the range of 20% to 80% by weight, preferably 45% to 80% by weight.

[0040] In a preferred embodiment, the nitrogen donor of component B may be melamine, and / or a melamine derivative (such as melem, melon, melamine cyanurate), and / or an ammonium derivative, and / or an isocyanurate derivative.

[0041] In a preferred embodiment, the polyphosphates and / or polyphosphonates from component B decompose while releasing non-flammable gases, forming a coating gas layer that prevents oxygen penetration to the substrate. The residual acidic polyphosphates act as catalysts for the expansion reaction by dehydrating the carbon-rich material and forming carbonaceous bubbles with the blowing agent. Furthermore, these polyphosphate compounds form a highly protective layer on the substrate.

[0042] In a preferred embodiment, the nitrogen donor and / or polyphosphate and / or polyphosphonate from component B is an inorganic nitrogen donor and / or inorganic polyphosphate and / or inorganic polyphosphonate, or a combination thereof. Non-limiting, but preferred, examples of such inorganic nitrogen donors and / or inorganic polyphosphates and / or inorganic polyphosphonates include ammonium polyphosphate (e.g., monoammonium phosphate and / or diammonium phosphate) and melamine polyphosphate.

[0043] In a preferred embodiment, component B further comprises at least one organic polyphosphate and organic phosphonate, such as a phosphonate ester, more preferably an aromatic polyphosphate and / or polyphosphonate, such as an aromatic polyphosphate and / or poly(m-phenylenemethyl)phosphonate from resorcinol bis(diphenylphosphate) and / or (1-methylethylidene)di-4,1-phenylenetetraphenyldiphosphate.

[0044] In a preferred embodiment, the oligophosphates and / or polyphosphates and / or polyphosphonates from component B are liquid, which improves the toughness of the final material without sacrificing the (thermo)mechanical performance or causing a dramatic softening effect. Such preferred oligophosphates or polyphosphates are aromatic polyphosphates with a number average molecular weight of more than 500 g / mol, preferably more than 1000 g / mol, and a phosphorus content of more than 4%, preferably more than 8%.

[0045] In a preferred embodiment, the inorganic phosphinate salt from component B acts as a flame retardant in the condensed phase, contributing to the carbonization of the polymer matrix and thereby protecting the substrate from heat and oxygen attack. At the same time, it acts via radical reaction in the gas phase, removing high-energy H and OH radicals from the combustion zone, which determine the propagation of flames and the release of heat. Such inorganic phosphinate salts are preferably used as halogen-free flame retardant additives in electrical and electronic applications.

[0046] In a preferred embodiment of the present invention, the one or more inorganic phosphinate salts in component B comprise at least one metal cation selected from the group consisting of aluminum, zinc, calcium, magnesium, iron, copper.

[0047] In a preferred embodiment of the present invention, one or more inorganic phosphinate salts in component B contain one, more or a combination of alkyl-containing substituents, alkylaryl-containing substituents and amido-containing substituents.

[0048] In a further preferred embodiment of the present invention, the inorganic phosphinate salt is one or a combination of alkyl-substituted aluminum phosphinates (such as aluminum dialkylphosphinates (e.g., aluminum methyl ethyl phosphinate, aluminum diethyl phosphinate, aluminum methyl butyl phosphinate, aluminum methyl cyclohexyl phosphinate, and / or aluminum diethyl phosphinate)), and / or amide-containing phosphinate salts (such as aluminum β-(N-phenylcarbamido)ethyl methyl phosphinate, aluminum β-(N-cyclohexylcarbamido)ethyl methyl phosphinate, and / or β-(N-butylcarbamido)ethyl methyl phosphinate).

[0049] In a preferred embodiment of the present invention, the nitrogen donor, polyphosphate, or polyphosphonate, and one or more inorganic phosphinate salts are solids having a particle size distribution with a D50 value of 0.1 to 100 μm and a D95 value of up to 200 μm, preferably a D50 value of 0.5 to 40 μm and a D95 value of up to 100 μm, and more preferably a D50 value of 0.5 to 20 μm and a D95 value of up to 50 μm. This improves the processability of the resin composition for L-AMT and optimizes print resolution and surface properties of 3D objects. The particle size distribution for determining the average particle size and respective D50 and D95 ​​values ​​of the filler is typically derived via static light scattering using Mie theory according to DIN / ISO 13320.

[0050] In a preferred embodiment of the present invention, component B is at least one of an inorganic nitrogen donor, an inorganic polyphosphate and an inorganic polyphosphonate, the amount of which is 5 to 80% by weight, preferably 20 to 70% by weight, more preferably 20 to 60% by weight, and even more preferably 20 to 55% by weight, based on the total weight of component B; at least one of an organic polyphosphate and an organic polyphosphonate, the amount of which is 5 to 95% by weight, preferably 5 to 50% by weight, more preferably 10 to 30% by weight, based on the content of the inorganic nitrogen donor and the at least one of the polyphosphate and polyphosphonate; one or more inorganic phosphinate salts, the amount of which is 20 to 80% by weight, preferably 30 to 80% by weight, more preferably 40 to 80% by weight, and even more preferably 45 to 80% by weight, based on the total weight of component B; It consists of:

[0051] By way of example, preferred ranges of combinations of nitrogen donors and / or polyphosphates and / or polyphosphonates and inorganic phosphinate salts that make up component B in the resin composition of the present invention can be derived from the table below or from the non-limiting examples disclosed herein. [Table A]

[0052] In a preferred embodiment of the present invention, the flame retardant species of Component B can be combined with a synergist, e.g., a halogen-free flame retardant such as a nitrogen donor (e.g., melamine and / or melamine derivatives such as melem, melon, melamine cyanurate, etc.), which results in improved flame resistance. This can be achieved through the addition of said synergist to the formulation and / or through coating said synergist onto the flame retardant Component B. Such synergist is preferably added in an amount of 0.1% to 20% by weight, preferably 1% to 10% by weight, based on the total weight of Component B.

[0053] Preferably, the nitrogen donor and at least one of the polyphosphates and polyphosphonates and one or more inorganic phosphinate salts in Component B are surface-functionalized and / or modified, e.g., functionalized with a polymerizable group such as (meth)acrylate or silanized via a radically polymerizable silane such as 3-methacryloyloxypropyltrimethoxysilane. Functionalized acidic or ionic components may be used to surface-modify the inorganic filler. Such modifications control and / or influence phenomena such as aggregation, mixture stability, and particle bonding to Component A. This improves the processability of the resin composition of the present invention and also results in superior mechanical performance of the 3D-processed material. Furthermore, such modifications preferably improve flame resistance via coating or functionalization with a flame-retardant material.

[0054] In a preferred embodiment of the present invention, component A further comprises a mono- or polyfunctional thermosetting component selected from group II, g forming a second polymerized network having a T >100°C; g In component A, the amount of one or more components of group II is in the range of 1 to 50% by weight, preferably 2 to 40% by weight, more preferably 3 to 30% by weight, and even more preferably 5 to 25% by weight, based on the total weight of the components of group I and group II, and the amount of one or more components of group I is in the range of 50 to 99% by weight, preferably 60 to 98% by weight, more preferably 70 to 97% by weight, and even more preferably 75 to 95% by weight.

[0055] In a preferred embodiment, one or more thermosetting components selected from Group II are g It functions as a TGE and enhances g >100°C, preferably T g >150°C, even more preferably T gA second polymeric network is formed having a temperature >200°C, and comprises one or more chemical species selected from the group consisting of allyl, vinyl, maleimide, citraconic imide, benzoxazine, epoxy, phenolic, cyanate ester, and phthalonitrile, as well as their oligomers, polymers, isomers, and / or combinations thereof, and preferably includes a second or further multiple curing step that is latent and selectively initiated simultaneously with or subsequent to the first photocuring step, thereby rendering the final formulation stable for storage at ambient conditions. Each crosslinked polymer network can be formed by a thermal curing reaction, a polymerization method known to those skilled in the art.

[0056] Preferred components from group II are monofunctional and / or polyfunctional thermosetting components, T g >100°C, preferably >150°C, more preferably >180°C, even more preferably >200°C, or T g The components serve to form a second polymerized network whose temperature range is between 80°C and 120°C, or between 120°C and 150°C, or between 150°C and 180°C, or between 180°C and 220°C, or between 220°C and 250°C, or between 250°C and 300°C. Thus, the components contribute to improved heat resistance (e.g., T according to ISO 75-1:2020) of the final photopolymer network. g or heat deflection temperature (HDT)) while maintaining toughness (e.g., as measured by elongation at break according to ISO 527). g is measured as the glass transition temperature of the network formed from the mono- and / or poly-functional thermosetting components in the absence of other chemical species, and is measured via DMA as described herein and derived from the maximum of the tan δ plot.

[0057] Preferably, the at least one photoinitiator is suitable for photoexcitation within the wavelength spectrum of 150 nm to 1000 nm, more preferably 200 nm to 550 nm, and is preferably present in an amount of 0.01 wt. % to 10 wt. %, preferably 0.1 wt. % to 7 wt. %, more preferably 0.2 wt. % to 5 wt. %, based on the weight of component A. This means that the photoinitiator is capable of being activated by light and initiating polymerization of the photocurable components in the formulation.

[0058] Preferred components from group II are monofunctional and / or polyfunctional thermosetting components, which are i) contain rigid functional groups, which play a role in forming the polymer backbone or polymer network, and provide the required high T g and which have a low tendency to polymerization shrinkage, such as aromatic groups and / or alicyclic groups and / or heterocyclic groups and / or groups showing strong intermolecular forces, such components being oligomers and / or prepolymers preferably having a high molecular weight (number average molecular weight >500 g / mol), and / or ii) have a low molecular weight (number average molecular weight <500 g / mol), which results in a high crosslink density and high overall heat resistance; and / or iii) High reactive group functionality (>2) for the reactive groups, which leads to high crosslink density and overall high heat resistance.

[0059] Preferred components from group II within component A can be effectively cured by a heat-curing step subsequent to the light-curing step of component A. The heat-curing step is carried out at a temperature higher than the initial processing temperature of the light-curing step, preferably above 100°C, more preferably above 120°C, even more preferably above 140°C, but at a temperature at which the formed material still exhibits sufficient thermal stability, preferably below 350°C, more preferably below 300°C, even more preferably below 200°C.

[0060] Preferred components from group II within component A can be effectively cured by a heat curing step following a light curing step of component A, which is carried out by applying heat directly via active heating in an oven (e.g., electric, gas, or solar oven) or indirectly via microwave irradiation, other light impulses (such as infrared) or secondary exothermic reactions such as thermal polymerization, and / or combinations thereof.

[0061] Some preferred examples of components from group II within component A include thermosetting components having one or more chemical species selected from the group consisting of monomers and / or oligomers and / or prepolymers of maleimide and citraconic acid derivatives, and their isomers, particularly itaconimides, represented by formula (II): [ka] During the ceremony, n is an integer from 1 to 10; R1 represents H, CH3 or CH2, R2 independently represents one or more linear, branched or cyclic C5-C alkyl groups selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl, hexyl, 2-ethylhexyl, octyl, decanyl, dodecanyl, acetic acid, propanoic acid, butanoic acid, pentanoic acid, undecanoic acid, dodecanoic acid, benzoic acid, and the corresponding esters, alkyl esters or aromatic esters, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, 4-isobutylcyclohexyl, cycloheptyl, cyclooctyl, adamantyl, isobornyl, salicyl, cholesteryl, phenyl, benzyl, phenethyl, propenyl, biphenyl, naphthyl, anthracenyl, pyrenyl, bis(methylene)oxy, bis(ethylene)oxy, bis(phenyl)methane, bis(phenyl)ethane, bis(phenyl)propane, bis(phenyl)butane, bis(phenyl)ether, bis(phenyl)thioether, bis(phenyl)amino and bis(phenyl)sulfone. 40It represents an aliphatic or aromatic residue, one or more of which groups are optionally individually bonded via an ester, amide, urea, urethane, carbonate, ether, thioether group, and these groups are optionally substituted with one or more C1-C6 alkyl, C1-C6 alkoxy, C1-C6 thioether, halogen, -NO2, -SO3H, -CF3, -OH, -NH2, -SH, -CN, -trimethoxysilyl, -triethoxysilyl, or one or more polymerizable groups from the material classes of maleimide and citraconic imide compounds and / or their isomers, in particular itaconimides.

[0062] Other preferred examples of components from group II within component A include polyfunctional allylic compounds containing rigid functional groups, which serve to form the polymer backbone or polymer network and provide the required high T gThe polyfunctional allyl compounds include aromatic groups and / or alicyclic groups and / or heterocyclic groups and / or groups exhibiting strong intermolecular forces (e.g., urethane groups and / or urea groups and / or carbonate groups), and have a low tendency to undergo polymerization shrinkage. Examples of such polyfunctional allyl compounds include 1,3,5-triallyl-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 2,4,6-triallyloxy-1,3,5-triazine, triallyl borate, 1,3,5- Benzene tricarboxylate, triallyl citrate, triallyl phosphate, tetraallyl pyromellitate, tetraallyloxyethane, diallyl propyl isocyanurate, diallyl isocyanurate, diallyl phthalate, 2,2-bis(4-allyloxy-3,5-dibromophenyl)propane, diallyl dicarbonate, diallyl carbonate, diallyl 1,4-cyclohexanedicarboxylate, 2,2-diallyl bisphenol A diacetate ether, diallyl terephthalate, diallyl isophthalate, diethyl diallyl malonate, 1,3-diallyl urea, 1,3-diallyl-2-thiourea, 2,4-diamino-6-diallylamino-1,3,5-triazine, diallyl oxalate, diallyl malonate, diallyl tetrabromophthalate, 2,6-diallyl-meta-cresol, N,N-diallylaniline, diallyl cyanamide, N,N-diallylmelamine, 2 ,2'-diallyl bisphenol A, N,N'-diallylpiperazine, 2,2-diallylpyrrolidine, diallylcarbamic acid tert-butyl ester, diallyl ether bisphenol A, diallyl phenylphosphonate, 5,5'-diallyl-[1,1'-biphenyl]-2,2'-diol, cyclohexanone diallyl acetal, 4,4'-diallyl-1,1'-biphenyl, 2,2-diallyl-4,4-biphenol, etc.

[0063] Some preferred examples of the one or more thermosetting components selected from Group II in component A include multifunctional epoxy compounds containing rigid functional groups, which serve to form the polymer backbone or polymer network and provide the required high T gand the like, which may be an aromatic group and / or an alicyclic group and / or a heterocyclic group and / or a group exhibiting strong intermolecular forces, and have a low tendency to undergo polymerization shrinkage. Examples of such components include bisphenol A, bisphenol F and / or bisphenol S derivatives, such as bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol S diglycidyl ether and / or diglycidyl 1,2-cyclohexanedicarboxylate, 4,4'-methylenebis(N,N-diglycidylaniline), trimethylolpropane triglycidyl ether, (3',4'-epoxycyclohexane)methyl-3,4-epoxycyclohexylcarboxylate, condensation products of 1-2-epoxy-4(2-oxiranyl)-cyclohexane and 2,2-bis(hydroxymethyl)1-butanol, bisphenol A novolac epoxy resins (e.g., SU-8 resins) and / or oligomers and / or prepolymers of derivatives thereof.

[0064] The component from Group II within Component A may also be a composition comprising two, three or more different components from Group II above.

[0065] The relative amounts of Component A and Component B in the resin composition of the present invention may be selected as follows: the amount of one or more photocurable components selected from Group I in Component A is in the range of 60% by weight to 95% by weight, preferably 65% ​​by weight to 90% by weight, and more preferably 70% by weight to 85% by weight, based on the total weight of the Group I components and Component B; the amount of flame retardant component B is in the range of 5 to 40% by weight, preferably 10 to 35% by weight, more preferably 15 to 30% by weight, based on the total weight of the Group I component and component B; The amount of one or more thermosetting components selected from Group II in Component A ranges from 1 to 50% by weight, preferably 2 to 40% by weight, more preferably 3 to 30% by weight, and even more preferably 5 to 25% by weight, based on the total weight of Component A.

[0066] By way of example, preferred range combinations of Component A and Component B in the hybrid resin composition of the present invention can be derived from the table below or the non-limiting examples disclosed herein. [Table B]

[0067] In a preferred embodiment, one or more thermosetting components selected from Group II in component A serve to form a secondary polymer network in the subsequent thermosetting step, improving the heterogeneity of the network. In this way, the cured material has i) an interpenetrating polymer network, or ii) semi-interpenetrating polymer networks, or iii) a sequential interpenetrating polymer network, or iv) polymer blends, Configure.

[0068] According to a preferred embodiment of the present invention, the resin composition of the present invention comprises at least one photoinitiator suitable for initiating polymerization by photoexcitation, preferably the photoexcitation is within the wavelength spectrum of 150 nm to 1000 nm, more preferably 200 nm to 550 nm, and the amount of photoinitiator is preferably an amount of 0.01 wt % to 10 wt %, preferably 0.1 wt % to 7 wt %, more preferably 0.2 wt % to 5 wt %, based on the total weight of component A. This means that the photoinitiator can be activated by light and initiate polymerization of the photocurable components in the formulation.

[0069] Photoinitiated polymerization (photopolymerization) is successful when the applied light irradiation is of an appropriate wavelength and sufficient intensity to activate the photoinitiator. In addition to the light irradiation being appropriate for the photoinitiator, it is also necessary that the entire formulation (including, for example, optional light-absorbing monomers, fillers, or additives) does not interfere with the interaction of the emitted light with the photoinitiator. The light irradiation applied in the present invention includes any wavelength and intensity capable of initiating polymerization. Preferred light wavelengths are 150 nm to 1000 nm, more preferably 200 nm to 550 nm. Suitable NIR, UV, or visible light sources may be used, including, but not limited to, lasers, LED light sources, or broadband mercury lamps. The light source may emit a broadband or narrowband light spectrum, or a combination thereof. The light source may emit continuous or pulsed light during a single or repeated exposure period, which may further be varied via exposure time or exposure intensity. An appropriately high process temperature increases the reactivity of the system, thereby enhancing the photoinduced structuring process. By adjusting the above parameters and variables, an optimized protocol for performing the described photopolymerization reaction can be obtained, resulting in optimal 3D fabrication via L-AMT.

[0070] In a preferred embodiment, the photo-induced curing step is performed utilizing a NIR (near infrared, 780-2500 nm) or UV / Vis (ultraviolet and visible, 150-780 nm) light source and corresponding optics, with the NIR configuration selected to enable 3D fabrication via two-photon photopolymerization, and the UV / Vis configuration selected from the group consisting of laser / DLP, LED / DLP, laser / LCD, and LED / LCD.

[0071] Preferred photoinitiators are radical photoinitiators, such as Norrish Type I photoinitiators, alone or in combination with one another, and can be selected from the group consisting of α-hydroxyketones, phenyl glyoxylate, benzil dimethyl ketal, α-aminoketones, mono- or bisacylphosphines, phosphine oxides, mono-, bis- or tetraacylsilanes, germanes, stannanes, and metallocenes. Some preferred examples include 2-hydroxy-2-methylpropiophenone, 1-hydroxycyclohexylphenyl ketone, methylphenyl glyoxylate, 2-benzyl-2-(dimethylamino)-4'-morpholinobutyrophenone, [1-(4-phenylsulfanylbenzoyl)heptylideneamino]benzoate, [1-[9-ethyl-6-(2-methylbenzoyl)carbazol-3-yl]ethylideneamino]acetate, 2,4,6-trimethylbenzoyldiphenylphosphine oxide (TPD). Polymeric Type I photoinitiators such as bis(cyclopentadienyl)bis[2,6-difluoro-3-(1-pyrryl)phenyl]titanium, bis(cyclopentadienyl)bis[2,6-difluoro-3-(1-pyrryl)phenyl]titanium, bis(cyclopentadienyl)bis[2,6-difluoro-3-(1-pyrryl)phenyl]titanium, bis(cyclopentadienyl)bis[2,6-difluoro-3-(1-pyrryl)phenyl]titanium, and / or Ominpol TP are also included.

[0072] A preferred photoinitiator may be a Norrish Type II photoinitiator. Some preferred examples include benzophenones (e.g., benzophenone, 4-methylbenzophenone, 4,4'-bis(diethylamino)benzophenone), benzoin, diketones (e.g., 9,10-phenanthrenequinone, 1-phenylpropane-1,2-dione, diacetyl or 4,4'-dichlorobenzyl and / or their derivatives), and thioxanthones (e.g., chloropropoxythioxanthone, isopropylxanthone, or 2,4-diethyl-9H-thioxanthen-9-one). Such Type II photoinitiators can be used in combination with coinitiators such as tertiary amines (e.g., aromatic tertiary amines such as N,N-dialkylaniline, -p-toluidine, or -3,5-xylidine, pN,N-dialkylaminophenylethanol, -benzoic acid derivatives, -benzaldehyde, or triethanolamine).

[0073] In a further preferred embodiment, a combination of said Type I and / or Type II photoinitiators may be used.

[0074] In some preferred embodiments, the resin compositions of the present invention comprise one or more flame retardant or smoke suppressant additives, such as aluminum hydroxide, magnesium hydroxide, calcium hydroxide, antimony oxide, molybdenum oxide (e.g., MoO), tin oxide, borax and / or zinc borate, ammonium molybdate, calcium molybdate and / or zinc molybdate, red phosphorus (preferably stabilized and / or microencapsulated in a suitable solvent), expandable graphite, organic additives (such as nitrogen donors and / or phosphorus-containing materials, preferably triphenylphosphine), or the like. and halogenated organic flame retardants (such as halogenated phosphates, halogenated diphenyl ethers, halogenated styrenes, halogenated epoxides, halogenated (meth)acrylates, and halogenated paraffins), and are contained in an amount of preferably 0.1 wt % to 10 wt %, more preferably 0.1 wt % to 5 wt %, based on the total weight of Components A and B, and the one or more flame retardant additives are preferably functionalized with a polymerizable group such as a (meth)acrylate.

[0075] Resin compositions of the type of the present invention can be processed in lithography-based 3D printing applications at elevated temperatures, where the resin compositions of the present invention are heated and then subjected to a layer-by-layer light-induced build-up step, where the photocurable components of the resin compositions of the present invention are structured by photocuring, resulting in 3D objects via lithography-based additive manufacturing methods, and exhibit the aforementioned desirable combination of flame resistance and (thermo)mechanical performance, i.e., improved heat resistance (e.g., T g In this way, a material is obtained that combines optimized toughness (e.g., measured via elongation at break) with high mechanical strength (e.g., measured via elongation at break).

[0076] In a preferred embodiment, hot lithography is used as a processing method that allows for the 3D structuring of resins with a high content of component B, which is a solid filler, oligomer, or prepolymer. In this context, the resin compositions of the present invention preferably have a viscosity of greater than 1 Pa·s, preferably greater than 5 Pa·s, at room temperature, as measured according to DIN EN ISO 2884-1, DIN EN ISO 2884-2, or according to the procedures described herein. The resulting materials exhibit improved flame resistance and (thermo)mechanical performance. This is demonstrated by the (thermo)mechanical properties and high flame resistance of 3D test specimens produced via the L-AMT disclosed herein.

[0077] In some preferred embodiments, one or more thermosetting components selected from Group II do not cure unless exposed to heat, i.e., temperatures higher than the processing temperature during the 3D printing process, typically above 50° C., making the thermosetting system latent and forming a resin formulation that is essentially storage-stable at room temperature, meaning that the storage stability is greater than 3 months, or greater than 6 months, or greater than 12 months (e.g., as measured by less than a 10% increase in viscosity as measured according to DIN EN ISO 2884-1, DIN EN ISO 2884-2, or according to the procedures described herein) until the 3D object is produced by a hot lithography process.

[0078] In a preferred embodiment, the heat curing step is carried out by applying heat indirectly via active heating in an oven (e.g., electric, gas, or solar oven) or via microwave irradiation, other light impulses (e.g., infrared), or secondary exothermic reactions such as thermal polymerization. Preferably, the heat-curable Group II component A is stable under ambient conditions and the processing conditions of the light curing step, so that the latent curing reaction must be induced.

[0079] In some preferred embodiments, at least one thermal initiator and / or catalyst may be used for the thermal curing of one or more thermosetting components selected from Group II and / or its comonomers. Suitable catalysts are preferably selected from tertiary amines (e.g., trialkylamines), particularly DABCO and / or DMAP and / or triethylamine and / or other aliphatic and aromatic secondary and / or tertiary amines, alkali salts of organic alcohols, phosphines, triphenylphosphonates, imidazoles, particularly substituted imidazoles such as 2-methyl-1-vinylimidazole, 2-phenylimidazole, 2-benzylimidazole and / or 2-ethyl-4-methylimidazole, and the like. Organic acids and / or peroxides, such as dibenzoyl peroxide, dilauroyl peroxide, dicumyl peroxide, tert-butyl perbenzoate and / or di-(tert-butyl) peroxide and / or 1,1,2,2-tetraphenyl-1,2-ethanediol and / or dicyandiamide, are preferably contained in an amount of 0.01% by weight to 10% by weight, more preferably 0.1% by weight to 5% by weight, based on the weight of the one or more thermosetting components selected from Group II.

[0080] In a further preferred embodiment, the resin composition of the present invention comprises one or more initiators for radical polymerization, particularly thermal initiators, which are suitable for thermal curing of one or more thermosetting components selected from Group II and / or post-curing of one or more photocurable components selected from Group I. Some preferred examples include azo compounds, more preferably 2,2'-azobis(isobutyronitrile) (AIBN) and / or azobis(4-cyanovaleric acid), and / or peroxides, more preferably organic peroxides, such as dibenzoyl peroxide, dilauroyl peroxide, dicumyl peroxide, tert-butyl perbenzoate and / or di-(tert-butyl)-peroxide and / or 1,1,2,2-tetraphenyl-1,2-ethanediol, which are preferably contained in an amount of 0.01 to 5% by weight, preferably 0.1 to 4% by weight, more preferably 0.2 to 3% by weight, based on the total weight of Component A.

[0081] In some preferred embodiments, the resin formulation further comprises a comonomer and / or cooligomer and / or coprepolymer that can be copolymerized with one or more thermosetting components selected from Group II and derivatives thereof.

[0082] In some preferred embodiments, the resin composition of the present invention comprises at least one polymerization inhibitor, preferably selected from the group consisting of quinones such as hydroquinone and / or benzoquinone, phenothiazine, diethylhydroxylamine, 4-tert-butylcatechol, butylated hydroxytoluene, pyrogallol, TEMPO and / or 4-hydroxy-TEMPO, in an amount of preferably 0.001 wt % to 1 wt %, preferably 0.005 wt % to 0.5 wt %, more preferably 0.01 wt % to 0.1 wt %, based on the total weight of component A.

[0083] In some preferred embodiments, the resin compositions of the present invention comprise at least one light absorber (such as a pigment or dye), preferably inorganic particles (such as titanium dioxide and / or carbon black), and / or organic UV absorbers (such as benzophenone derivatives, benzotriazole derivatives, triazine derivatives, thioxanthones), hindered amine light stabilizers (such as Chimassorb, Tinuvin and / or Uvinul products), and / or diethyl 2-(4-hydroxy-3-methoxybenzylidene) The light absorber selected from the group consisting of 2-(4-hydroxybenzylidene)malonate, ethyl-2-cyano-3-(4-hydroxy-3-methoxyphenyl)acrylate, dimethyl 2-(4-hydroxybenzylidene)malonate, and / or (E)-ethyl 2-(3-ethoxy-4-hydroxybenzylidene)-3-oxobutanoate is preferably contained in an amount of 0.001% to 2% by weight, preferably 0.01% to 1% by weight, and more preferably 0.02% to 0.5% by weight, based on the total weight of component A.

[0084] The aforementioned synergistic flame retardant additives, photoinitiators, thermal initiators, catalysts, inhibitors, light absorbers, and other additives may be polymeric and / or further functionalized with polymerizable functional groups and may be polymerized in situ with Component A in accordance with preferred embodiments of the present invention.

[0085] In some preferred embodiments, the resin composition of the present invention includes an additional toughness modifier selected from the group consisting of thermoplastic resins, such as polypropylene, polyethylene, polyamide, polyethylene oxide, and / or polypropylene oxide, reactive rubbers, particularly butadiene-acrylonitrile copolymers, and / or natural polymers such as cellulose and / or gelatin. Such thermoplastic resins are preferably terminated or functionalized with one or more reactive groups susceptible to radical or ionic polymerization (e.g., (meth)acrylates, (meth)acrylamides, vinyl esters, vinyl ethers, or cyclic ethers such as styrene compounds, epoxy compounds, or oxetanes), and / or flexible linkers, particularly monomers containing such reactive groups with long aliphatic chains and / or ethylene glycol spacers. The amount of the additional toughness modifier is preferably 0.5% to 30% by weight, preferably 2% to 15% by weight, more preferably 5% to 10% by weight, based on the total weight of component A.

[0086] In some preferred embodiments, the resin composition of this invention contains additional organic and / or inorganic fillers. Such mixtures are generally described as composites. Preferred organic fillers include, but are not limited to, core-shell particles, block copolymers, PTFE, high-performance polymers, thermoplastics, particularly polyamides, polycarbonates, polystyrenes, polyoxymethylenes, poly(etherimides), polyethersulfones or polysulfones, and rubbers. Preferred inorganic fillers include metals, metal oxides, and / or ceramics (e.g., SiO2, ZrO2, TiO2, ZnO, or mixtures thereof, having an average particle size of 0.5 μm to 100 μm), talc, clay, silicates such as silica and / or mica, glass powders (especially quartz and glass ceramics, which are preferred as nano- or microfillers, having an average particle size of 0.1 μm to 100 μm), carbon black, graphene, and graphite. The average particle size of the filler can be determined via static light scattering using Mie theory according to DIN / ISO 13320 for the determination of average particle size and particle size distribution. In a second embodiment, such organic or inorganic fillers may be spherical, platelet-like and / or fibrous (e.g., nanofibers, whiskers, and / or mixtures thereof, spherical, fractured and / or defined three-dimensional structures, in particular graphite and / or two-dimensional structures, in particular graphene monolayers).

[0087] Preferably, the filler may be surface-modified (e.g., silanized via a radically polymerizable silane such as 3-methacryloyloxypropyltrimethoxysilane). Surface modification of inorganic fillers such as ZrO or TiO may be achieved using functionalized acid phosphates (e.g., 10-methacryloyloxydecyldihydrogenphosphate). Such modifications can control and / or influence phenomena such as agglomeration, mixture stability, and particle bonding to the polymer matrix.

[0088] The resin composition of the present invention may further comprise the following components, either alone or in combination with one another: stabilizers (such as UV stabilizers or anti-aging agents), antioxidants, colorants (such as dyes or pigments), antibacterial agents, antistatic agents, softeners or plasticizers or lubricants, wetting agents, matting agents, adhesion promoters, rheology modifiers, thixotropic agents, dispersants, optical brighteners, opacifiers, defoamers and / or UV absorbers.

[0089] The resin compositions of the present invention can be cured to form any object including coatings, adhesives, sealants, inks, or can be cured layer by layer or sequentially to form a 3D object, preferably via a 3D printing process such as stereolithography, and then post-cured via a secondary or multiple further thermal curing steps.

[0090] The resin mixture of Components A, B, and photoinitiators disclosed herein can be mixed in various ratios and additional components as described above. The preferred mixing ratios for the formulations are as follows: At least one or more photocurable components selected from group I of component A as a preferred combination of RD-subgroup i), TNM-subgroup ii), and CA-subgroup iii): 60% to 95% by weight, preferably 65% ​​to 90% by weight, more preferably 70% to 85% by weight, based on the total weight of the group I components and component B in A As component B, at least one combination of a nitrogen donor and at least one polyphosphate and polyphosphonate with one or more inorganic phosphinate salts (synergistic flame retardant mixture): 5% to 40% by weight, preferably 10% to 35% by weight, more preferably 15% to 30% by weight, based on the total weight of the group I components in A and component B. At least one photoinitiator: 0.01 to 10% by weight, preferably 0.1 to 7% by weight, more preferably 0.2 to 5% by weight, based on the weight of the group I components in component A. Optionally, one or more thermosetting components selected from group II of component A (thermosetting T gEnhancer): 0% to 50% by weight, preferably 2% to 40% by weight, more preferably 3% to 30% by weight, and even more preferably 5% to 25% by weight, based on the total weight of the Group I component and the Group II component in Component A Optionally, a thermosetting agent suitable for one or more thermosetting components selected from Group II: 0.01% to 20% by weight, preferably 0.1% to 15% by weight, more preferably 0.2% to 10% by weight, based on the weight of one or more thermosetting components selected from Group II in component A.

[0091] The presence of one or more photocurable components selected from group I in component A provides a cured material with reduced crosslink density, resulting in higher toughness (e.g., as measured by elongation at break), while maintaining heat resistance due to the rigid polymer backbone derived from the respective reactive diluent (subgroup i)).

[0092] The presence of multifunctional TNMs (subgroup ii)) with a molecular weight greater than 500 g / mol, preferably greater than 1000 g / mol, in one or more photocurable components selected from group I in component A serves to form a first polymeric network with improved toughness (e.g., increased elongation at break).

[0093] One or more photocurable components (reactive diluents, toughness modifiers and / or crosslinkers) selected from group I within component A are selected to participate in the photoinduced structuring step, provide sufficient green strength, and allow 3D structuring of the formulation, preferably via hot lithography using temperatures between 30 and 150°C in the build-up step. The presence of crosslinker CA (subgroup iii) further improves the green strength and 3D structuring of the formulation. The photopolymer formed after the photocuring step is preferably T g It is characterized as a tough photopolymer exhibiting a temperature above 25°C and an elongation at break above 3%.

[0094] The presence of flame-retardant component B contributes to improved flame resistance of the resulting 3D printed material. Combining a nitrogen donor and a polyphosphate and / or polyphosphonate with one or more inorganic phosphinate salts in a synergistic mixing ratio results in a material with improved flame resistance (up to 1.5 mm thickness or greater according to UL94V0) while minimizing the required loading of flame-retardant component B (less than 40 wt%). This results in improved (thermo)mechanical performance (e.g., T g This allows the production of flame-resistant 3D objects with a temperature of >90°C; elongation at break >3%. Furthermore, the use of liquid organic polyphosphates and / or polyphosphonates allows the production of flame-resistant 3D objects with improved toughness. Depending on the composition of component A, there are preferred compositions for component B depending on the process. Polyphosphates and / or polyphosphonates increase the green strength of the produced 3D objects and facilitate post-processing. Liquid organic polyphosphates and / or polyphosphonates reduce viscosity, leading to improved process control, such as reduced release force and reduced foaming. In addition to achieving a (synergistic) flame-retardant effect while minimizing the amount of component B used, it is further desirable to select its components to optimize the manufacturing process, improve green properties, and facilitate post-processing.

[0095] The presence of one or more multifunctional thermosetting components selected from Group II in component A contributes to the formation of T g Contributes to the formation of a second polymerized network at temperatures >100 °C, thereby improving the heat resistance (e.g., T according to ISO 75-1:2020) of the final photopolymer network. g or heat deflection temperature (HDT)) while maintaining toughness (e.g., as measured by elongation at break according to ISO 527-1:2019 and ISO 527-2:2019).

[0096] According to a further aspect, the present invention relates to a method for producing an object from the resin composition of the present invention, in which the resin composition is subjected to a light-induced structuring step, optionally followed by a thermally induced curing step. In a preferred embodiment, the light-induced structuring step is followed by a light-induced post-curing step. As will be apparent to those skilled in the art, the light-mediated curing process may also be an additive manufacturing process, more preferably a 3D printing process with respective UV and / or thermal post-treatment steps to obtain a final product with desired chemical, mechanical, and thermal properties. Thus, the resin formulation of the present invention can be used as a resin formulation for producing a 3D object via additive manufacturing. The resulting 3D object exhibits high toughness while achieving a balance of excellent flame resistance. Example applications for 3D objects additively manufactured from these materials include jigs, fixtures, automotive parts (e.g., housings and interior trim, fuel contact parts such as connectors), electronic connectors, components for printed circuit boards, packaging and cooling structures for electronic devices, chip mounts, robotic hands, battery housings, and / or other applications requiring high flame resistance, mechanical durability, and thermal stability at temperatures above 50°C.

[0097] In a preferred embodiment of the method, the photo-induced structuring step is performed using light having a wavelength in the range of 150 nm to 2500 nm. Preferably, the photo-induced structuring step is performed using a NIR light source (780-2500 nm) or a UV / Vis light source (150-780 nm) and corresponding optics, where the NIR configuration is selected to enable 3D fabrication via two-photon photopolymerization, and the UV / Vis configuration is selected from the group consisting of laser / DLP, LED / DLP, laser / LCD, and LED / LCD.

[0098] Typically, conventional L-AMT requires formulations with viscosities below 1 Pa·s at ambient conditions or slightly above room temperature and below 35°C, and is not suitable for temperatures rarely exceeding 35°C. For resin viscosities above 1 Pa·s at temperatures above 35°C, L-AMT for high-temperature, high-viscosity resins (e.g., hot lithography) becomes the printing process of choice.

[0099] In a preferred embodiment, the photo-induced structuring step is carried out at an elevated processing temperature of the resin composition, preferably between 25° C. and 150° C., more preferably between 35° C. and 100° C., and even more preferably between 40° C. and 90° C. This is done to reduce the viscosity of the resin composition of the present invention during the structuring step, which provides processability when the content of Components A and B is high, potentially having high molecular weights and high softening or melting points.

[0100] In a preferred embodiment, a layer of the resin composition is formed on a carrier plate using, for example, a recoater blade. To facilitate this, the resin composition of the present invention preferably has a viscosity of 0.01 to 70 Pa·s, preferably 0.1 to 30 Pa·s, at the processing temperature, and the formed layer preferably has a thickness of less than 2 mm, more preferably less than 1 mm, and even more preferably less than 0.8 mm.

[0101] Preferably, the thermally induced curing step is carried out at a temperature higher than the processing temperature of the light-induced structuring step, preferably at a temperature of 100°C to 400°C, more preferably at a temperature of 120°C to 400°C or at a temperature of 100°C to 300°C.

[0102] Furthermore, in accordance with a preferred embodiment of the present invention, the thermally induced curing step comprises heating the object in an oven and / or exposing the object to electromagnetic radiation and / or inducing a secondary exothermic reaction, such as thermal polymerization, within the object.

[0103] In a more general way, the light-induced structuring step preferably comprises building the object layer-by-layer on a build platform to obtain a stack of structured layers, each structured layer being formed by the following steps: - forming an unstructured layer of a resin composition of a predetermined thickness; - selectively projecting light onto the unstructured layer according to a desired pattern, thereby hardening the resin composition to obtain a structured layer. is obtained by

[0104] The light-induced structuring step is preferably carried out to build an object by 3D printing, in which the layers of the object are formed one after the other and on top of each other by forming material layers of a defined thickness of the resin composition between a transparent or at least partially transparent carrier (such as a plate, carrier film or container bottom) and a mechanically adjustable build platform or between an object at least partially formed on the build platform, and the material layers thus defined are position-selectively hardened, in particular by irradiation through the transparent or at least partially transparent carrier, to provide the desired shape of the layer.

[0105] According to a preferred embodiment, the photo-induced structuring step is carried out using a first radiation source, the radiation of which is applied to the resin composition through a transparent carrier plate, and heating of the layer of resin composition to be structured is carried out using a second radiation source, the carrier plate being essentially opaque to the radiation of the second radiation source. In this way, the carrier plate is heated by the radiation of the second radiation source, but the radiation does not substantially impinge on the layer of resin composition, thereby allowing the resin composition indirectly heated through the carrier plate to be structured by the radiation of the first radiation source. In particular, one or more thermosetting components selected from Group II in component A are not thermally cured by the second radiation source.

[0106] In a preferred embodiment, a layer of the resin composition is formed on a carrier plate (e.g., using a recoater blade), and the layer is cured via a first photocuring step, and the thickness of the formed layer is greater than 10 μm, preferably greater than 25 μm, more preferably greater than 50 μm, even more preferably greater than 80 μm, and less than 1000 μm, preferably less than 800 μm, more preferably less than 500 μm, and even more preferably less than 400 μm, and the cured thickness is preferably less than 1.1 times the layer height of the 3D printing process.

[0107] In a preferred embodiment, the object is manufactured from the resin composition of the present invention and the light-induced structuring step is an additive manufacturing process and / or a 3D printing process, preferably based on stereolithography, digital light processing, material jetting or inkjet printing, more preferably hot lithography techniques.

[0108] After the light-induced curing step of the resin of the present invention, a thermal curing step may be performed to obtain further cure. The heating step can be performed in the temperature range of 100-350°C, preferably 100-300°C, and can be divided into one or more individual curing steps, each at a defined temperature and a defined heating rate (e.g., 10 K / min) for a defined time interval. Non-limiting examples of such thermal curing steps include: Method A → 160℃ for 10 hours, Method B: 170°C for 0.5 hours and 150°C for 2 hours. Method C: 200°C for 0.5 hours and 160°C for 10 hours. Method D → 2 hours at 120°C and 2 hours at 150°C.

[0109] In a preferred embodiment, the thermally induced curing step is performed after the photo-structured 3D printing step or after an additional UV post-treatment step, and the molded 3D object is cured at a temperature higher than the initial processing temperature of the photo-structuring step, preferably above 100°C, more preferably above 120°C, even more preferably above 140°C, and at which the formed material still exhibits sufficient thermal stability, preferably below 350°C, more preferably below 300°C, even more preferably below 200°C.

[0110] In a preferred embodiment, a part cleaning step is performed between the photo-structured 3D printing step and the subsequent thermally induced curing step, and such part cleaning step can be in a physical form (e.g., centrifugation, shaking, pressurized air, vacuum) and / or chemical form (e.g., solvent cleaning or steam cleaning with isopropyl alcohol and / or glycol ethers and / or aromatic solvents and / or alkanes).

[0111] In a preferred embodiment, a thermally induced curing step is performed after the photo-structured 3D printing step, and the molded 3D object is cured at a temperature higher than the initial processing temperature of the photo-structuring step, and the heat is applied either directly via active heating in an oven (e.g., electric oven, gas oven, or solar oven), or indirectly via microwave irradiation, other light impulses (such as infrared), or secondary exothermic reactions such as thermal polymerization, and / or combinations thereof.

[0112] In preferred embodiments, hardened materials and / or articles are formed which are characterized by exhibiting improved flame resistance meeting UL94 V-0 classification, preferably with a wall thickness of less than 4 mm, more preferably less than 2 mm, and even more preferably less than 1.5 mm.

[0113] The materials and / or objects of the present invention, obtained by subjecting the resin composition of the present invention to a light-induced structuring step and optionally thereafter to a thermally induced curing step or post-curing step via light or heat, are preferably characterized in that the object exhibits the following material properties: i) A tensile modulus of 1 MPa or more, a tensile strength of 1 MPa or more, an elongation at break of 100% or more, and a flame retardancy rating of UL94 V-0<3mm; or ii) A tensile modulus of 500 MPa or more, a tensile strength of 10 MPa or more, an elongation at break of 20% or more, and a flame retardancy rating of UL94 V-0<3mm; or iii) A tensile modulus of 1500 MPa or more, a tensile strength of 25 MPa or more, an elongation at break of 5% or more, a glass transition temperature of 70°C or more, a temperature at 1 GPa storage modulus of 30°C or more, and a flame retardancy rating of UL94 V-0<3mm; or iv) Tensile modulus of elasticity ≥ 2000 MPa, tensile strength ≥ 30 MPa, elongation at break ≥ 3%, glass transition temperature ≥ 90°C, temperature value at 1 GPa storage modulus ≥ 45°C, and flame retardancy rating UL94 V-0<3mm.

[0114] In preferred embodiments, cured materials and / or objects formed from the resin compositions of the present invention have a thermal conductivity of greater than 1 W / mK, more preferably greater than 1.5 W / mK, and even more preferably greater than 2 W / mK.

[0115] As used herein, the term "polymer" refers to a molecule composed of repeating structural units connected by covalent chemical bonds and characterized by a significant number of repeating units (e.g., 10 or more repeating units, often 50 or more repeating units, and often 100 or more repeating units) and a high molecular weight (e.g., 5,000 Da, 10,000 Da, or 20,000 Da or more). Polymers are typically the polymerization product of one or more monomer precursors. The term "polymer" includes homopolymers, or polymers consisting essentially of a single repeating monomer subunit. The term "polymer" also includes copolymers, formed when two or more different types of monomers are combined within the same polymer. Copolymers are composed of two or more monomer subunits and include random, block, alternating, segmented, graft, tapered, and other copolymers.

[0116] As used herein, "oligomer" refers to a molecule composed of repeating structural units connected by covalent chemical bonds and characterized by a smaller number of repeating units than a polymer (e.g., 10 or fewer repeating units) and a lower molecular weight than a polymer (e.g., less than 20,000 Da or less than 10,000 Da). An oligomer may be the polymerization product of one or more monomer precursors. In one embodiment, an oligomer or a monomer is not, by itself, considered a polymer.

[0117] "Prepolymer" refers to a polymer or oligomer whose molecules are capable of further polymerization through reactive groups.

[0118] The mixture of oligomers and polymers may further crosslink to create a polymer network.

[0119] Oligomer and polymer mixtures can be characterized and distinguished from other oligomer and polymer mixtures by measuring molecular weight and molecular weight distribution.

[0120] As used herein, the term "molecular weight" refers to number average molecular weight as measured by gel permeation chromatography (GPC) or size exclusion chromatography (SEC) in a suitable solvent (typically tetrahydrofuran) calibrated with polystyrene standards. [Example]

[0121] Embodiments of the present disclosure will be described in more detail by reference to the following non-limiting examples, which are presented for illustrative purposes only and should not be construed as limiting the scope of the invention as defined by the appended claims.

[0122] All chemicals used herein were purchased commercially and used without further purification.

[0123] Curable compositions according to the invention were prepared by mixing the components in a beaker at temperatures between 25 and 60°C using an IKA Anchor Stirrer or a Hauschild Engineering Speed ​​Mixer DAC150FVZ. The resin was mixed until a homogeneous blend or stable suspension was obtained. The resin blend was further degassed in a Goldbrunn 450 vacuum oven until no mixing bubbles or micro-foam were detected in the blend.

[0124] Rheological measurements of the exemplary resin formulations were performed using an AntonPaar MCR102 rheometer. For evaluation of resin viscosity, each resin formulation was run in rotational mode (PP-25, shear rate 50 s -1 The viscosity was measured using a temperature program of 25-70°C, a heating rate of 0.5 K / min, and a measuring gap of 1 mm. All statements regarding viscosity throughout the specification and claims can be determined in this way or in accordance with DIN EN ISO 2884-1 or DIN EN ISO 2884-2.

[0125] (Thermo)mechanical and fire test specimens of the final materials according to the invention were produced from the exemplary resin compositions in a CaligmaDLP printer (405 nm) via hot lithography technology from Cubicure GmbH. During the printing process, all printer parts in contact with the formulation (i.e., material container, recoating unit, recoating blade, and build platform) were heated to a process temperature of 80°C. All 3D objects produced with the CaligmaDLP were printed in a laser printer with a light output intensity of approximately 50 mW cm. -2 The pixel size on the top surface of the material container was set to about 50 μm.

[0126] After each print job, the 3D printed specimens were mechanically removed from the build platform using a blade, and excess resin was removed using a wipe or via solvent cleaning with isopropanol. All 3D printed specimens were subjected to 100% intensity (approximately 150 mW cm) irradiation using a Uvitron IntelliRay 600. ―2 The sample was then UV post-cured for two 5-minute periods using a broadband UV light source (approximately 280-550 nm), flipping the sample between exposure cycles to ensure the photo-curing step was complete. Thermal post-treatment was performed in a ThermoScientific Heratherm OMH60 oven using the temperature protocol (heating rate set at 10 K / min) according to the method described: Method A → 30 minutes at 170°C and passive cooling to 80°C (for CE1-CE4 and E1-E4)

[0127] Tensile tests on the 3D-printed specimens were performed using a Zwick / Roell ProLine Z010TH materials testing machine. Tests were performed in accordance with DIN EN ISO 527 using 5A specimens. The tensile modulus was measured at a strain rate of 1 mm / min over a range of 0.05–0.25% elongation, followed by a further test at a strain rate of 10 mm / min.

[0128] DMA measurements to evaluate the storage modulus plot and the glass transition temperature (Tg) were performed using a dynamic viscoelasticity measuring device (PerkinElmer DMA8000) with a set temperature program (30 °C to 160 °C) and a heating rate of 2 K / min. 3 ) was measured in a three-point bending mode. The test conditions were set at a frequency of 1 Hz, a strain of 50 μm, and a preload of 0 N. The glass transition temperature Tg was derived from the maximum value of the loss factor plot (tan δ).

[0129] The horizontal burn test was performed according to the UL94 HB standard, except that the flame was positioned vertically during the HB test, rather than at a 45° angle as specified in the UL94 standard. A propane-fueled NetzschTaurus KBK917 (Kleinbrennkasten) combustion chamber was used. The specimens were stored in a Memmert HPP110eco oven at 23°C and 50% relative humidity for 96 hours prior to the burn test. The specimen dimensions were 90 mm long, 12.7 mm wide, and 1–3 mm thick. The burner flame height was adjusted to 20 mm and centered directly below the cantilevered end of the specimen. The burn time during the HB test was 10 seconds, after which the flame was removed from the end of the specimen. Possible test results are explained in the footnotes of Table 2.

[0130] Vertical flame tests were conducted according to the UL94 standard. A propane-fueled NetzschTaurus KBK917 (Kleinbrennkasten) combustion chamber was used. Specimens were stored in a Memmert HPP110eco oven at 23°C and 50% relative humidity for 96 hours prior to the flame test. The specimens measured 90 mm in length, 12.7 mm in width, and 1-3 mm in thickness. The burner flame was adjusted to a height of 20 mm and positioned directly below and centered on the specimen, covering the lower 10 mm of the specimen during the test. After 10 seconds of burning, the flame was removed. As soon as the flame ceased to form, the burner flame was repositioned below the specimen and maintained for 10 seconds. The initial and second burning times were recorded. Possible test results are explained in the footnotes of Table 2.

[0131] [Example 1 to Example 4] Examples 1-4 (E1-4) are examples of resin compositions of the present invention, and only Examples E2-E4 are examples of resin compositions of the present invention, which are composed of a combination of a photocurable component A and a flame-retardant component B to ensure a synergistic flame-retardant effect. Comparative Examples 1-4 (CE1-4) respectively comprise a photocurable resin and flame-retardant composition containing only component A without flame retardant B (in the case of CE1), and a composition of component A containing a single component of the flame retardant (FR) of component B (in the case of CE2-4).

[0132] [Table 1]

[0133] <Preparation of Resin Composition> CE1: 30 g of monofunctional photocurable component A (isobornyl methacrylate) as reactive diluent RD, 45 g of photocurable component A (polyester methacrylate EBECRYL-4766) as toughness modifier (TNM), and 25 g of photocurable component A (tris(2-hydroxyethyl)isocyanurate triacrylate (THEICTA)) as crosslinker (CA) were homogenized with 3 g (3 phr) of photoinitiator ethylphenyl(2,4,6-trimethylbenzoyl)phosphinate (TPO-L) and 0.3 g (0.3 phr) of thermal initiator dicumyl peroxide (DCP).

[0134] CE2: 22.5 g of monofunctional photocurable component A (isobornyl methacrylate) as RD, 33.75 g of photocurable component A (polyester methacrylate EBECRYL-4766) as TNM, 18.75 g of photocurable component A (tris(2-hydroxyethyl)isocyanurate triacrylate (THEICTA)) as CA, and 25 g of organic polyphosphate (FR, an oligomeric aromatic polyphosphate from (1-methylethylidene)di-4,1-phenylenetetraphenyldiphosphate (CAS 5945-33-5 and CAS 181028-79-5)) as component B were homogenized with 2.25 g (3 phr) of photoinitiator ethylphenyl(2,4,6-trimethylbenzoyl)phosphinate (TPO-L) and 0.225 g (0.3 phr) of thermal initiator dicumyl peroxide (DCP).

[0135] CE3: 22.5 g of monofunctional photocurable component A (isobornyl methacrylate) as RD, 33.75 g of photocurable component A (polyester methacrylate EBECRYL-4766) as TNM, 18.75 g of photocurable component A (tris(2-hydroxyethyl)isocyanurate triacrylate (THEICTA)) as CA, and 25 g of inorganic polyphosphate (ammonium polyphosphate (CAS 68333-79-9) as FR) as component B were homogenized with 2.25 g (3 phr) of photoinitiator ethylphenyl(2,4,6-trimethylbenzoyl)phosphinate (TPO-L) and 0.225 g (0.3 phr) of thermal initiator dicumyl peroxide (DCP).

[0136] CE4: 22.5 g of monofunctional photocurable component A (isobornyl methacrylate) as RD, 33.75 g of photocurable component A (polyester methacrylate EBECRYL-4766) as TNM, 18.75 g of photocurable component A (tris(2-hydroxyethyl)isocyanurate triacrylate (THEICTA)) as CA, and 25 g of inorganic phosphinate salt (diethylphosphinic acid aluminum salt (CAS 225789-38-8) as FR) as component B were homogenized with 2.25 g (3 phr) of photoinitiator ethylphenyl(2,4,6-trimethylbenzoyl)phosphinate (TPO-L) and 0.225 g (0.3 phr) of thermal initiator dicumyl peroxide (DCP).

[0137] E1: 22.5 g of monofunctional photocurable component A (which is isobornyl methacrylate) as RD, 33.75 g of photocurable component A (which is polyester methacrylate EBECRYL-4766) as TNM, 18.75 g of photocurable component A (which is tris(2-hydroxyethyl)isocyanurate triacrylate (THEICTA)) as CA, and a combination of component B, i.e., 12.5 g of organic polyphosphate ((1-methylethylidene)di-4,1-phenylenetetraphenyldiphosphate) as FR. Component B, a combination of 12.5 g of inorganic polyphosphate (ammonium polyphosphate (CAS 68333-79-9)) as FR, was homogenized with 2.25 g (3 phr) of the photoinitiator ethylphenyl(2,4,6-trimethylbenzoyl)phosphinate (TPO-L) and 0.225 g (0.3 phr) of the thermal initiator dicumyl peroxide (DCP).

[0138] E2: 22.5 g of monofunctional photocurable component A (which is isobornyl methacrylate) as RD, 33.75 g of photocurable component A (which is polyester methacrylate EBECRYL-4766) as TNM, 18.75 g of photocurable component A (which is tris(2-hydroxyethyl)isocyanurate triacrylate (THEICTA)) as CA, and 12.5 g of component B as a synergistic combination, i.e., organic polyphosphate ((1-methylethylidene)di-4,1-phenylenetetraphenyldiphos) as FR. Component B, a synergistic combination of 12.5 g of an inorganic phosphinate salt (aluminum diethylphosphinate (CAS 225789-38-8)) as FR, was homogenized with 2.25 g (3 phr) of the photoinitiator ethylphenyl(2,4,6-trimethylbenzoyl)phosphinate (TPO-L) and 0.225 g (0.3 phr) of the thermal initiator dicumyl peroxide (DCP).

[0139] E3: 22.5 g of monofunctional photocurable component A (which is isobornyl methacrylate) as RD, 33.75 g of photocurable component A (which is polyester methacrylate EBECRYL-4766) as TNM, 18.75 g of photocurable component A (which is tris(2-hydroxyethyl)isocyanurate triacrylate (THEICTA)) as CA, and 12.5 g of component B as a synergistic combination, i.e., inorganic polyphosphate (ammonium phosphate) as FR. Component B, a synergistic combination of 12.5 g of inorganic phosphinate salt (aluminum diethylphosphinate salt (CAS 225789-38-8)) as FR, was homogenized with 2.25 g (3 phr) of the photoinitiator ethylphenyl (2,4,6-trimethylbenzoyl)phosphinate (TPO-L) and 0.225 g (0.3 phr) of the thermal initiator dicumyl peroxide (DCP).

[0140] E4: 22.5 g of monofunctional photocurable component A (which is isobornyl methacrylate) as RD, 33.75 g of photocurable component A (which is polyester methacrylate EBECRYL-4766) as TNM, 18.75 g of photocurable component A (which is tris(2-hydroxyethyl)isocyanurate triacrylate (THEICTA)) as CA, and 5 g of component B as a synergistic combination, i.e., 5 g of organic polyphosphate ((1-methylethylidene)di-4,1-phenylenetetraphenyldiphosphate (CAS 5945-33-5 and CAS 181028- Component B, a synergistic combination of 10 g of an FR (an oligomeric aromatic polyphosphate from CAS 68333-79-5), 10 g of an FR (ammonium polyphosphate (CAS 68333-79-9)), and 10 g of an FR (aluminum diethylphosphinate (CAS 225789-38-8)), was homogenized with 2.25 g (3 phr) of the photoinitiator ethylphenyl(2,4,6-trimethylbenzoyl)phosphinate (TPO-L) and 0.225 g (0.3 phr) of the thermal initiator dicumyl peroxide (DCP).

[0141] [Table 2]

[0142] <Results (vertical combustion test)> CE1 (3mm / 1.5mm / 1mm) burns completely within the first 10 seconds of contact with the flame. The flame spreads steadily to the top of the specimen.

[0143] CE2 (3mm / 1.5mm / 1mm) burns completely after the first 10 seconds of contact with the flame. The flame spreads more slowly than CE1 and flickers, allowing the positive effect of the flame retardant additive to be observed.

[0144] The positive effect of the flame retardant additive can be observed as CE3 (3 mm) does not burn after the first 10 seconds after contact with the flame, but burns completely after the second 10 seconds after contact with the flame. CE3 (1.5mm / 1mm) burns completely within the first 10 seconds of contact with a flame.

[0145] CE4 (3mm) burns with a very small flame for 20 seconds after the first 10 seconds of contact with the flame, but burns completely after the second 10 seconds of contact with the flame. In the second burning stage, strong smoke is observed, but the positive effect of the flame retardant additive can be observed. CE4 (1.5mm / 1mm) burns completely within the first 10 seconds of contact with a flame.

[0146] E1 (3mm / 1.5mm / 1mm) burns completely within the first 10 seconds of contact with a flame.

[0147] E2 (3mm / 1.5mm / 1mm) burns completely within the first 10 seconds of contact with a flame.

[0148] E3 (3mm) does not burn after first contact with flame, but burns for 9 seconds after second contact with flame - Pass (X3). E3 (1.5mm) does not burn after first contact with flame, but burns for 7 seconds after second contact with flame - Pass (X3). E3 (1mm) does not burn after first contact with flame, but burns for 12 seconds after second contact with flame - Pass (X3).

[0149] E4 (3mm) does not burn after first contact with flame, but burns for 14 seconds after second contact with flame - Pass (X3). E4 (1.5mm / 1mm) burns completely within the first 10 seconds of contact with a flame.

[0150] <Results (horizontal combustion test)> CE1 (1.5 mm) The flame does not reach the second mark (100 mm) on the specimen within 1 minute.

[0151] CE2 (1.5 mm) The flame does not reach the second mark (100 mm) on the specimen within 1 minute.

[0152] CE3 (1.5 mm) The flame does not reach the first mark (25 mm) on the specimen within 1 minute.

[0153] CE4 (1.5 mm) The flame does not reach the first mark (25 mm) on the specimen within 1 minute.

[0154] E1 (1.5 mm) The flame does not reach the second mark (100 mm) on the specimen within 1 minute.

[0155] E2 (1.5 mm) The flame does not reach the first mark (25 mm) of the test piece within 1 minute.

[0156] E3 (1.5 mm) The flame does not reach the first mark (25 mm) on the specimen within 10 seconds.

[0157] E4 (1.5 mm) The flame does not reach the first mark (25 mm) on the specimen within 10 seconds.

[0158] <Consideration> All formulations tested exhibited viscosities in the range of 0.1–20 Pa·s at processing temperatures, which provides a suitable range for 3D fabrication of these formulations via hot lithography (see Figure 1 ).

[0159] Two materials that stood out in the fire tests were 3D printed from Formulations E3 and E4. Both of these formulations contain promising and effective combinations of flame retardant components, demonstrating a synergistic combination of flame retardant additives according to the disclosed component B. The E3 photopolymer exhibited the highest modulus (2960 MPa) and T of the materials of the present invention. g However, material E4 offers the most promising combination of both (thermo)mechanical and flame retardant material properties: it passes the vertical flame test (3 mm), has a significantly increased elongation at break (about 5%) and still has a high T g(approximately 100°C), this material solution has clear advantages in certain applications over the other material combinations tested.

[0160] This elongation-improving effect was also clearly demonstrated when comparing Compound CE2 with Compound CE1, as shown in Figure 2. Although there was a significant decrease in modulus and strength values, the elongation at break improved from 11.7% to 22.3% when comparing CE1 and CE2. Compounds CE3 and CE4 showed the opposite effect, with a decrease in elongation and an increase in strength and modulus values ​​compared to Compound CE1. This is thought to be due to the positive effect of the solid flame retardant additives, which are inorganic phosphinate salt (aluminum diethylphosphinate) and inorganic polyphosphate (ammonium polyphosphate).

[0161] As shown in Figure 1, E4 exhibits a decrease in viscosity with increasing temperature compared to E3, further improving the processability of the materials of the present invention. As clearly shown in CE3 and CE4, increasing the solid flame retardant component significantly increases the viscosity at a specific temperature. Comparing CE2 and CE1 shows that adding liquid component B to the matrix results in a decrease in viscosity. In Figure 3, a clear shift in tan δ from CE1 to CE2 is detected, indicating the effect of component B being a liquid organophosphate ester. The shift in tan δ toward higher temperatures due to the solid flame retardant as component B is not as strong, but is clearly detectable.

[0162] The storage modulus shown in Figure 4 also demonstrates the softening effect of the liquid organophosphate ester as component B, confirming the reinforcing effect of the solid flame retardant.

Claims

1. A resin composition for 3D printing of highly flame resistant objects, comprising: a) a curable component A, the curable component A comprising one or more photocurable components selected from Group I consisting of (meth)acrylates, meth)acrylamides, vinyl esters, vinyl ethers, vinylamides, N-vinyl compounds, vinyl carbonates, vinyl carbamates, maleimides, itaconates, fumarates, styrene compounds, cyclic ethers such as epoxy compounds or oxetanes, benzoxazines, oxazolines, and cyanoacrylates, wherein the one or more photocurable components selected from Group I form a first polymerized network; and b) a flame retardant component B, which is a combination of i) at least one of a nitrogen donor and a polyphosphate and a polyphosphonate, and ii) one or more inorganic phosphinate salts, wherein the weight ratio of i) to ii) is preferably from 1 / 9 to 9 / 1; c) at least one photoinitiator, said at least one photoinitiator being suitable for polymerization by photoexcitation; Including, the amount of curable component A ranges from 60% to 95% by weight, preferably from 65% to 90% by weight, more preferably from 70% to 85% by weight, based on the combined weight of components A and B; the amount of flame retardant component B ranges from 5% to 40% by weight, preferably from 10% to 35% by weight, more preferably from 15% to 30% by weight, based on the combined weight of components A and B; and the amount of photoinitiator ranges from 0.01% to 10% by weight, based on the weight of component A alone; The above resin composition.

2. Component A further comprises one or more thermosetting components selected from Group II consisting of monofunctional or polyfunctional components, and T ｇ forming a second polymerized network having a T ｇ 2. The resin composition according to claim 1, wherein the amount of one or more components from Group II in Component A, which function as an enhancer, is in the range of 1 to 50% by weight, preferably 2 to 40% by weight, more preferably 3 to 30% by weight, and even more preferably 5 to 25% by weight, based on the total weight of the components from Group I and Group II, and the amount of one or more components from Group I is in the range of 50 to 99% by weight.

3. The resin composition according to claim 1 or 2, wherein component A consists of one or more components selected from Group I and, optionally, one or more components selected from Group II.

4. The component selected from Group I is Subgroup i) one or more monofunctional photocurable components having the formula (I): X-Y Formula (I) and comprising a reactive species Y and pendant groups X susceptible to radical or cationic polymerization, wherein the one or more components of subgroup i) form a polymer backbone upon photoinduced curing, and the backbone preferably has a T above 25°C. ｇ the one or more monofunctional photocurable components having Subgroup ii) one or more mono- or polyfunctional photocurable components, which copolymerize with said one or more components of subgroup i) via a curing mechanism, preferably have a molecular weight greater than 500 g / mol, function as toughness modifiers, and preferably have an elongation at break greater than 10% and a T of greater than 0° C. ｇ the one or more mono- or polyfunctional photocurable components forming a polymeric network having Optionally, Subgroup iii) one or more photocurable cross-linking components, referred to as cross-linking agents (CA), which copolymerize with said one or more components of subgroup i) and subgroup ii) via a curing mechanism; The resin composition according to any one of claims 1 to 3, which consists of a combination of:

5. 5. The resin composition of claim 4, wherein the amount of one or more components in subgroup i) is in the range of 5% to 60% by weight, the amount of one or more components in subgroup ii) is in the range of 5% to 95% by weight, and the amount of one or more components in subgroup iii) is in the range of 5% to 95% by weight, based on the total weight of the components in subgroups i), ii), and iii).

6. 6. The resin composition according to claim 1, wherein in component B, the amount of at least one of the nitrogen donor, polyphosphate, and polyphosphonate is in the range of 20% to 80% by weight, preferably 20% to 55% by weight, based on the total weight of component B, and the amount of the one or more inorganic phosphinate salts is in the range of 20% to 80% by weight, preferably 45% to 80% by weight.

7. The resin composition according to any one of claims 1 to 6, wherein in component B, at least one of the nitrogen donor, polyphosphate, and polyphosphonate comprises or consists of at least one of an inorganic nitrogen donor, inorganic polyphosphate, and inorganic polyphosphonate, preferably selected from the group consisting of ammonium polyphosphate, in particular monoammonium phosphate and / or diammonium phosphate, and melamine polyphosphate.

8. The resin composition of claim 7, wherein in component B, the at least one of the nitrogen donor and the polyphosphate and the polyphosphonate further comprises one of an organic polyphosphate and an organic polyphosphonate, such as a phosphonate ester.

9. 9. The resin composition of claim 1, wherein the one or more inorganic phosphinate salts in component B comprise at least one metal cation selected from the group consisting of aluminum, zinc, calcium, magnesium, iron, and copper.

10. 10. The resin composition of any one of claims 1 to 9, wherein the one or more inorganic phosphinate salts in component B comprise one, more, or a combination of alkyl-containing substituents, alkylaryl-containing substituents, and amido-containing substituents.

11. The resin composition according to any one of claims 1 to 10, wherein in component B, at least one of the nitrogen donor, polyphosphate, and polyphosphonate, and the one or more inorganic phosphinate salts are solids, and the solids have a particle size distribution of a D50 value of 0.1 to 100 µm and a D95 value of at most 200 µm, preferably a D50 value of 0.5 to 40 µm and a D95 value of at most 100 µm, and more preferably a D50 value of 0.5 to 20 µm and a D95 value of at most 50 µm.

12. Component B is at least one of an inorganic nitrogen donor and an inorganic polyphosphate and an inorganic polyphosphonate, in an amount of 5 to 80 wt. %, preferably 20 to 70 wt. %, more preferably 20 to 60 wt. %, and even more preferably 20 to 55 wt. %, based on the total weight of component B; at least one of an organic polyphosphate and an organic polyphosphonate, the amount of which is 5 to 95% by weight, preferably 5 to 50% by weight, more preferably 10 to 30% by weight, based on the content of the nitrogen donor and the at least one of the polyphosphate and polyphosphonate; one or more inorganic phosphinate salts in an amount of 20 to 80% by weight, preferably 30 to 80% by weight, more preferably 40% to 80% by weight, and even more preferably 45% to 80% by weight, based on the total weight of component B; The resin composition according to any one of claims 8 to 11, comprising:

13. The resin composition according to any one of claims 1 to 12, wherein the nitrogen donor, at least one of polyphosphate and polyphosphonate, and one or more inorganic phosphinate salts in component B are surface functionalized and / or modified, for example, functionalized with a polymerizable group such as a (meth)acrylate, or silanized via a radically polymerizable silane such as 3-methacryloyloxypropyltrimethoxysilane.

14. The resin composition according to any one of claims 2 to 13, wherein the one or more thermosetting components selected from Group II have one or more chemical species selected from the group consisting of allyl, vinyl, maleimide, citraconic imide, benzoxazine, epoxy, phenol, cyanate ester, and phthalonitrile, and oligomers thereof, polymers thereof, and isomers thereof.

15. 15. The resin composition according to any one of claims 1 to 14, wherein the at least one photoinitiator is suitable for photoexcitation within the wavelength spectrum of from 150 nm to 1000 nm, more preferably from 200 nm to 550 nm, and is preferably present in an amount of from 0.01 wt. % to 10 wt. %, preferably from 0.1 wt. % to 7 wt. %, more preferably from 0.2 wt. % to 5 wt. %, based on the weight of component A.

16. The resin composition may include one or more flame retardant or smoke suppressant additives, such as aluminum hydroxide, magnesium hydroxide, calcium hydroxide, antimony oxide, molybdenum oxide (e.g., MoO ３ 16. The resin composition of claim 1, wherein the one or more flame retardant additives are selected from the group consisting of: tin oxide, borax and / or zinc borate, ammonium molybdate, calcium molybdate and / or zinc molybdate, red phosphorus (preferably stabilized and / or microencapsulated in a suitable solvent), expandable graphite, and halogenated organic flame retardants (such as halogenated phosphates, halogenated diphenyl ethers, halogenated styrenes, halogenated epoxides, halogenated (meth)acrylates, and halogenated paraffins), preferably present in an amount of 0.1 wt % to 10 wt %, more preferably 0.1 wt % to 5 wt %, based on the total weight of the resin composition, and wherein the one or more flame retardant additives are preferably functionalized with a polymerizable group such as a (meth)acrylate.

17. The resin composition according to any one of claims 1 to 16, having a viscosity of more than 1 Pa·s, preferably more than 5 Pa·s, at room temperature.

18. The resin composition according to any one of claims 1 to 17, comprising one or more initiators for radical polymerization, in particular thermal initiators.

19. 20. A method for producing an object by 3D printing, wherein the resin composition according to any one of claims 1 to 18 is subjected to a light-induced structuring step, optionally post-curing via secondary light irradiation, optionally followed by a thermally induced curing step.

20. 20. The method of claim 19, wherein the photoinduced structuring step is performed with light having a wavelength in the range of 150 nm to 2500 nm.

21. 21. The method according to claim 19 or 20, wherein the photo-induced structuring step is carried out at a processing temperature of the resin composition between 25°C and 150°C, more preferably between 35°C and 100°C, even more preferably between 40°C and 90°C.

22. 22. The method according to claim 21, wherein the resin composition has a viscosity of 0.01 to 70 Pa.s, preferably 0.1 to 30 Pa.s, at the processing temperature.

23. 23. The method according to claim 21 or 22, wherein the thermally induced curing step is carried out at a temperature higher than the processing temperature of the light-induced structuring step, preferably at a temperature of 100°C to 400°C, more preferably at a temperature of 120°C to 400°C or at a temperature of 100°C to 300°C.

24. 24. The method of any one of claims 19 to 23, wherein the thermally induced curing step comprises heating the object in an oven, and / or exposing the object to electromagnetic radiation, and / or inducing a secondary exothermic reaction in the object, such as thermal polymerization.

25. The light-induced structuring step comprises building the object layer by layer on a build platform to obtain a stack of structured layers, each structured layer being formed by the following steps: - forming an unstructured layer of a resin composition of a predetermined thickness; - selectively projecting light onto the unstructured layer according to a desired pattern, thereby hardening the resin composition to obtain a structured layer; The method according to any one of claims 19 to 24, wherein the method is obtained by

26. An article produced from the resin composition according to any one of claims 1 to 18 by the method according to any one of claims 19 to 25.

27. 27. An article according to claim 26, having flame resistance corresponding to a UL 94 V-0 classification, preferably having a wall thickness of less than 4 mm, more preferably less than 2 mm, even more preferably less than 1.5 mm.

28. i) a tensile modulus of 1 MPa or greater, a tensile strength of 1 MPa or greater, an elongation at break of 100% or greater, and a flame retardancy rating of UL94 V-0<3mm; or ii) a tensile modulus of 500 MPa or greater, a tensile strength of 10 MPa or greater, an elongation at break of 20% or greater, and a flame retardancy rating of UL94 V-0<3mm; or iii) a tensile modulus of 1500 MPa or greater, a tensile strength of 25 MPa or greater, an elongation at break of 5% or greater, a glass transition temperature of 70°C or greater, a temperature value at 1 GPa storage modulus of 30°C or greater, and a flame retardancy rating of UL94 V-0<3mm; or iv) a tensile modulus of 2000 MPa or more, a tensile strength of 30 MPa or more, an elongation at break of 3% or more, a glass transition temperature of 90°C or more, a temperature value at 1 GPa storage modulus of 45°C or more, and a flame retardancy rating of UL94 V-0<3mm; 28. The article of claim 26 or 27, wherein the article exhibits the property:

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