Abstract: The present invention relates to prepolymers of formula (I), a process for the production of the prepolymers, photocurable compositions, comprising the prepolymers of formula (I) and their use in a photopolymerization 3D printing process. In contrast to usual urethane (meth)acrylates. The prepolymers of formula (I) can be prepared without using toxic isocyanates and exhibit pending hydroxyl groups along their molecule backbone which allow for the introduction of further side chains or side groups to improve, for example, the interaction with inorganic fillers.

Abstract: The present invention relates to photocurable compositions, comprising a limonene-based (meth)acrylate (A) obtainable by reacting a) 1 equivalent of a compound of formula, especially (I) with 1 to 3 equivalents of a compound of formula (II) in the presence of a catalyst and an inhibitor at elevated temperature and its use in a photopolymerization 3D printing process. The limonene-based (meth)acrylate (A) significantly increases stiffness and glass transition temperatures of photo-cured acrylate compositions. While such effects are usually achieved with the use of aromatic or bisphenol A based compounds, the limonene-based (meth)acrylate (A) offers a sustainable alternative at much lower viscosity.

Abstract: Described herein are photocurable compositions, (A) a polyester urethane acrylate, or methacrylate (A), (B) an acrylamide, or methacrylamide component (B), and (C) a photoinitiator (C), where the polyester urethane acrylate, or methacrylate (A) is obtained by reacting (A1) a hydroxyalkylacrylate, or hydroxyalkylmethacrylate, (A2) an aliphatic diisocyanate, an aliphatic polyisocyanate, a cycloaliphatic diisocyanate, a cycloaliphatic polyisocyanate, an aromatic diisocyanate, or an aromatic polyisocyanate, or mixtures thereof, (A3) a polyester polyol, and (A4) optionally a second polyol. The compositions, from which cured three-dimensional shaped articles having high toughness, high E modulus and impact strength can be made, are particularly suitable for the production of three-dimensional articles by stereolithography.

Abstract: The present invention relates to photocurable compositions, comprising (A1) a N-vinyloxazolidinone of formula (I), wherein R1, R2, R3 and R4 are independently of each other a hydrogen atom or an organic group having not more than 10 carbon atoms, (A2) optionally one, or more second reactive diluents, (B) one, or more oligomers, and (C) a photoinitiator (C), wherein the amount of component (A1) is 5 to 70% by weight based on the amount of components (A1), (A2) and (B), wherein the viscosity of said photocurable composition is in the range 10 to 3000 mPa·s, preferably 10 to 1500 mPa·s at 30° C. The compositions, from which cured three-dimensional shaped articles having balanced mechanical properties combining stiffness with high toughness can be made, are particularly suitable for the production of three-dimensional articles by stereolithography and photopolymer jetting.

Abstract: The present invention relates to photoinitiator compounds of the formula (1) wherein X is O, S or a direct bond; Y is O, S or CR9R10; R1, R2, R3, R4, R5, R6, R7 and R8 independently of each other are hydrogen, halogen, C1-C18alkyl, C5-C10cycloalkyl, C2-C18alkenyl, phenyl, C1-C4alkoxy, C5-C7cycloalkoxy, phenoxy, C1-C4-alkylthio, C5-C7cycloalkylthio, phenylthio, di(C1-C4alkyl)amino, di(C5-C7cycloalkyl)amino, N-morpholinyl, N-piperidinyl or a group of formula (2) provided that one or more than one of R1, R2, R3, R4, R5, R6, R7 or R8 is a group of formula (2); R9, R10 independently of each other are hydrogen, C1-C18alkyl, C2-C12alkenyl, C5-C10cycloalkyl, phenyl-C1-C4alkyl, phenyl or together with the C atom to which they are attached form a 5-membered, 6-membered or 7-membered ring; and R11 is hydrogen, C1-C18alkyl, C5-C10cycloalkyl, C2-C12alkenyl, phenyl-C1-C4alkyl or phenyl.

Abstract: The present invention relates to photoinitiator compounds of the formula (1) wherein X is O, S or a direct bond; Y is O, S or CR9R10; R1, R2, R3, R4, R5, R6, R7 and R8 independently of each other are hydrogen, halogen, C1-C18alkyl, C5-C10cycloalkyl, C2-C18alkenyl, phenyl, C1-C4alkoxy, C5-C7cycloalkoxy, phenoxy, C1-C4-alkylthio, C5-C7cycloalkylthio, phenylthio, di(C1-C4alkyl)amino, di(C5-C7cycloalkyl)amino, N-morpholinyl, N-piperidinyl or a group of formula (2) provided that one or more than one of R1, R2, R3, R4, R5, R6, R7 or R8 is a group of formula (2); R9, R10 independently of each other are hydrogen, C1-C18alkyl, C2-C12alkenyl, C5-C10ocycloalkyl, phenyl-C1-C4alkyl, phenyl or together with the C atom to which they are attached form a 5-membered, 6-membered or 7-membered ring; and R11 is hydrogen, C1-C18alkyl, C5-C10cycloalkyl, C2-C12alkenyl, phenyl-C1-C4alkyl or phenyl.

Abstract: A method for producing a tridimensional structure by 3D printing comprises: (a) ejecting an object material through a first print head, the object material comprising a radically curable compound and a photoinitiator; (b) ejecting a supporting material through a second print head, the supporting material comprising a cationically polymerizable compound and a photoacid generator; (c) radiation curing the object material and the supporting material; steps (a) to (c) are repeated several times in order to form the tridimensional structure layer by layer, and the object material and the supporting material comprise at least one common boundary surface; and (d) removing the cured supporting material by treatment with an aqueous medium. The supporting material is suitable for supporting overhanging components and structures located above hollow spaces.

Abstract: A method for producing a tridimensional structure comprises: (a) ejecting an object material through a first print head; (b) ejecting a first pre-supporting material through a second print head; (b?) ejecting a second pre-supporting material through a third print head, the pre-supporting materials comprising liquid components which form a solid supporting material when brought together; (c) radiation curing the object material; steps (a) to (c) are repeated several times in order to form the tridimensional structure layer by layer, and the object material and the supporting material comprise at least one common boundary surface; and (d) removing the cured supporting material by treatment with an aqueous medium. The supporting material is suitable for supporting overhanging components and structures located above hollow spaces.

Abstract: The present invention relates to a fluid-absorbent article, comprising an indicator for feces especially of newborn and breast-feeded babies, which is applied to a carrier material and to an indicator for feces especially of newborn and breast-feeded babies and substances present in urine indicating kidney or vascular diseases, suitable for fluid-absorbent articles such as diapers, comprising at least one indicator-substance which changes color as a result of contact with proteins.

Abstract: The invention relates to a time temperature indicator comprising a) at least one photo-chromic colorant introduced into and/or atop a matrix substrate and charged by exposure to UV light; b) at least a transparent colorless or a transparent colored light absorbing protecting layer adhered to the underlying layer a) which contains the photo-chromic colorant; characterized in that the light absorbing protecting layer comprises 1-50 wt % of an UV light absorber or an UV light absorber mixture and 0.1-10 wt % of an optical brightener wherein the weight ratio of the UV light absorber and optical brightener is 0.1-10.

Abstract: The present invention relates to a photochromic ink, the process for its preparation which is based on a spiropyran powder obtainable by melting, cooling and crushing, and to a new form of a spiropyran obtainable thereby. Said process to prepare a photochromic ink comprises the steps of a) heating and melting the spiropyran at a temperature below 250 C, b) cooling the melt to obtain a solidified spiropyran, c) crushing the solidified spiropyran to obtain a powder, d) optionally adding the powder to a binder providing the basis for the photochromic ink.

Abstract: The invention relates to the use of highly sterically hindered nitroxyl radicals or of quinone methides or of mixtures thereof as in-can stabilizers for UV-curable resins.

Abstract: The present invention relates to a photochromic ink, the process for its preparation which is based on a spiropyran powder obtainable by melting, cooling and crushing, and to a new form of a spiropyran obtainable thereby. Said process to prepare a photochromic ink comprises the steps of a) heating and melting the spiropyran at a temperature below 250 C, b) cooling the melt to obtain a solidified spiropyran, c) crushing the solidified spiropyran to obtain a powder, d) optionally adding the powder to a binder providing the basis for the photochromic ink.

Abstract: The invention relates to a time temperature indicator comprising a) at least one photo-chromic colorant introduced into and/or atop a matrix substrate and charged by exposure to UV light; b) at least a transparent colorless or a transparent colored light absorbing protecting layer adhered to the underlying layer a) which contains the photo-chromic colorant; characterized in that the light absorbing protecting layer comprises 1-50 wt % of an UV light absorber or an UV light absorber mixture and 0.1-10 wt % of an optical brightener wherein the weight ratio of the UV light absorber and optical brightener is 0.1-10.

Abstract: The invention relates to novel photoinitiators of formula (I) wherein A is —O—, —CH2?, CH(CH3)— or —C(CH3)2?, and R is methyl or trimethylsilyl, and R may in addition be hydrogen when A is simultaneously the group —C(CH3)2?. The invention relates also to compositions comprising (A) at least one ethylenically unsaturated compound, (B) a photoinitiator of formula (I), (C) optionally further binders or additives, (D) optionally further photoinitiators or co-initiators. Compositions comprising (A) an ethylenically unsaturated compound that contains at least one aminoacrylate, (B) a photoinitiator of formula (II) or (III), (C) optionally further binders or additives, (D) optionally further photoinitiators or co-initiators.

Abstract: The invention relates to a radiation curable coating or an ink composition comprising a photoinitiator and a stabilizer blend of a sterically hindered nitroxyl radical and a quinone methide.

Abstract: The invention relates to novel photoinitators of formulae (I), (II), (III), (IV), (V) and (VI) wherein R1 and R2 are each independently of the other C1-C8alkyl; C1-C4alkyl substituted by OH, C1-C4alkoxy, —COO(C1-C8alkyl), (C1-C4alkyl)-COO—, —CN, benzyl, phenyl or by —N(R15)(R16); C3-C6alkerlyl, benzyl, —CH2—C6H4—(C1-C4alkyl) or phenyl; or R1 and R2 together are unbranched or branched C2-C9alkylene or C3-C6-oxa- or -azaalkylene; R3, R4, R5 and R6 are each independently of the others hydrogen, C1-C8alkyl, C3-C6alkenyl, benzyl, —CH2—C6H4—(C1-C4alkyl) or phenyl; R3 and R4 together and/or R5 and R6 together are unbranched or branched C2-C9alkylene; A is CI, Br, —O—R9, —N(R11)(R12) or —S—R18, A? is —O—, —NH— or —NR11—; A? is CI, Br, —O—R9, —N(R11)(R12) or —S—R18 or hydrogen, X is —O—R10 or —N(R13)(R14), n is an integer from 1 to 10, preferably an integer from 1 to 4, especially 1, 2 or 3; R7 is a linker; R8 is a bivalent C2-C3alkylele radical.

Abstract: The invention relates to a radiation curable coating or an ink composition comprising a photoinitiator and a stabilizer blend of a sterically hindered nitroxyl radical and a quinone methide.

Abstract: The Invention relates to novel ketones of formulae (I) and (II) wherein R1, R2, R3 and R4 are, for example, C1-C8alkyl, R5 is, for example, hydrogen, A is CI, Br, -0-R7, —NR8R9 or —S—R16, A? is —O—, —NH— or —NR8—, X and Y are each independently of the other —O—R10 or —N(R11)(R12), n is an integer from 1 to 10, R6 is, for example, an n-valent radical of linear or branched C2-C20alkyl the carbon chain of which may be interrupted by cyclohexanediyl, phenylene, —CH(OH)—, —C(C2H5)(CH2—CH2—OH)—, —C(CH3)(CH2—CH2—OH)—, —C(CH2—CH2—OH)2—, —N(CH3)—, —N(C2H5)—, —N(CH2—CH2—OH)—, —CO—O—, —O—CO—, —P(CH2—CH2—OH)—, —P(O)(CH2—CH2—OH)—, -0-P(O—CH2—CH2—OH)—O—, -0-P(O)(0-CH2—CH2—OH)—O—, —O-cyclohexanediyl-C(CH3)2-Cyclohexanediyl-O—, —O-phenylene-C(CH3)2-phenylene-O—, —O-phenylene-CH2-phenylene-O—, —Si(CH3)2—, -0-Si(CH3)2—O—, —O—Si(CH3)(0-CH3)—O—, —Si(CH3)(R17)—O—Si(CH3)(R18)—, 5-(2-hydroxyethyl)-[1,3,5]triazinane-2,4,6-trione-1,3-diyl and/or by from one to nine oxygen atoms.

Abstract: Compounds of formula (I), wherein R1 is hydrogen or alkyl; R2 is C1-C4alkoxy or a morpholino radical; and R3 is hydrogen or C1-C4alkoxy, are suitable for improving the solubility of specific photoinitiators in formulations and accordingly enhance the storage stability of formulations comprising a photoinitiator and compounds of formula (I)