Abstract: Method for producing a plastic layer having a layer thickness of less than 200 ?m on an upper side of a substrate includes the following steps: applying plastic powder to the substrate upper side by means of a powder scattering device, then cleaning the substrate underside, then melting the applied plastic powder in a furnace, as a result of which the plastic layer is formed on the substrate, and cooling the substrate, wherein the substrate is transported continuously from method step to method step.

Abstract: Method for producing a plastic layer having a layer thickness of less than 200 ?m on an upper side of a substrate, comprising the following steps: applying plastic powder to the substrate upper side by means of a powder scattering device, then cleaning the substrate underside, then melting the applied plastic powder in a furnace, as a result of which the plastic layer is formed on the substrate, and cooling the substrate, wherein the substrate is transported continuously from method step to method step.

Abstract: A photosensitive composition of (a) a compound of formula (Ia) or (Ib) and (b) a bifunctional acrylate or methacrylate.

Abstract: Compounds of formulae (Ia) and (Ib) 1

Abstract: Compounds of formulae (Ia) and (Ib) wherein the substituents R1 are each independently of the other hydrogen or methyl, R2 is an unsubstituted C1-C20alkyl group or a C1-C20alkyl group which is substituted by one or more than one substituent selected from the group consisting of hydroxy, C6-C14aryl and halogen, an unsubstituted phenyl group or a phenyl group which is substituted by one or more than one substituent selected from the group consisting of C1-C6alkyl, hydroxy or halogen, or is a radical of formula —CH2—OR3, wherein R3 is an unsubstituted C1-C20alkyl group or a C1-C20alkyl group which is substituted by one or more than one substituent selected from the group consisting of hydroxy, C6-C14aryl and halogen, an unsubstituted phenyl group or a phenyl group which is substituted by one or more than one substituent selected from the group consisting of C1-C6alkyl, hydroxy and halogen, or is a C2-C6alkenyl group, a C2-C20acyl group or an unsubstituted cyclohexylcarbonyl group or

Abstract: Compounds of formulae (Ia) and (Ib) ##STR1## wherein the substituents R.sub.1 are each independently of the other hydrogen or methyl, R.sub.2 is an unsubstituted C.sub.1 -C.sub.20 alkyl group or a C.sub.1 -C.sub.20 alkyl group which is substituted by one or more than one substituent selected from the group consisting of hydroxy, C.sub.6 -C.sub.14 aryl and halogen, an unsubstituted phenyl group or a phenyl group which is substituted by one or more than one substituent selected from the group consisting of C.sub.1 -C.sub.6 alkyl, hydroxy or halogen, or is a radical of formula --CH.sub.2 --OR.sub.3, wherein R.sub.3 is an unsubstituted C.sub.1 -C.sub.20 alkyl group or a C.sub.1 -C.sub.20 alkyl group which is substituted by one or more than one substituent selected from the group consisting of hydroxy, C.sub.6 -C.sub.14 aryl and halogen, an unsubstituted phenyl group or a phenyl group which is substituted by one or more than one substituent selected from the group consisting of C.sub.1 -C.sub.

Abstract: The invention relates to compounds having at least one vinyl ether group which also contain in the molecule at least one further functional group selected from acrylate, methacrylate, epoxy, alkenyl, cycloalkenyl and vinylaryl groups, to compositions, especially for stereolithography, comprising those vinyl ether compounds, and to a method of producing three-dimensional objects using those compositions.

Abstract: The invention relates to compounds having at least one vinyl ether group which also contain in the molecule at least one further functional group selected from acrylate, methacrylate, epoxy, alkenyl, cycloalkenyl and vinylaryl groups, to compositions, especially for stereolithography, comprising those vinyl ether compounds, and to a method of producing three-dimensional objects using those compositions.

Abstract: The invention relates to compounds having at least one vinyl ether group which also contain in the molecule at least one further functional group selected from acrylate, methacrylate, epoxy, alkenyl, cycloalkenyl and vinylaryl groups, to compositions, especially for stereolithography, comprising those vinyl ether compounds, and to a method of producing three-dimensional objects using those compositions.

Abstract: Novel (meth)acrylates which also contain urethane groups and other polymerizable groups in one and the same molecule and can be polymerized either by means of free radicals and/or cationically are used for the production of coatings, adhesives, photoresists, solder masks or in stereolithography. The mouldings produced therefrom contain a coherent, homogeneous network and have high strength properties, in particular mechanical properties.

Abstract: A process is described for the preparation of photopolymerizable compositions, wherein the photopolymerizable compositions can be photopolymerized by the irradiation of emission lines of differing wavelength from a UV/VIS laser light source, and contain a photopolymerizable compound and at least two photoinitiators, by adjusting the sensitivity to radiation. The ratio between the concentrations of the individual photoinitiators is so adjusted that the composition has virtually the same optical density for the radiation of the different emission lines at which the photoinitiators are effective.

Abstract: Liquid radiation-curable formulation, in particular for stereolithography, based on at least one compound that contains radically polymerizable groups, and at least one photoinitiator suitable for the polymerization, which formulation additionally contains a polyoxyalkylene-polysiloxane block copolymer that is selected from copolymers of the chemical formulae ##STR1## wherein: R.sup.1 is a hydrogen atom or a C.sub.1 -C.sub.8 alkyl group;R.sup.2 is a methyl or phenyl group;[T] is a polysiloxane group [PS] terminated as described in the specification in more detail;[PS] is the group of formula ##STR2## and [Alk] is an alkylene group of 3 to 10 carbon atoms, as well as novel block copolymers of formulae (I) and (II). The cured formulations have, inter alia, superior impact strength.

Abstract: The invention relates to compounds having at least one vinyl ether group which also contain in the molecule at least one further functional group selected from acrylate, methacrylate, epoxy, alkenyl, cycloalkenyl and vinylaryl groups, to compositions, especially for stereolithography, comprising those vinyl ether compounds, and to a method of producing three-dimensional objects using those compositions.

Abstract: Novel (cyclo)aliphatic epoxy compounds that contain at least one acrylate group in the molecule and at least one cycloaliphatic epoxy group can be used for the production of coating formulations, adhesives, photoresists or in stereolithography. As they contain a cohesive homogeneous network, the three-dimensional objects produced have very good green strength and very good strength properties.

Abstract: A process is described for the preparation of photopolymerizable compositions, wherein the photopolymerizable compositions can be photopolymerized by the irradiation of emission lines of differing wavelength from a UV/VIS laser light source, and contain a photopolymerizable compound and at least two photoinitiators, by adjusting the sensitivity to radiation. The ratio between the concentrations of the individual photoinitiators is so adjusted that the composition has virtually the same optical density for the radiation of the different emission lines at which the photoinitiators are effective.

Abstract: Novel (meth)acrylates containing urethane groups Novel (meth)acrylates which also contain urethane groups and other polymerizable groups in one and the same molecule and can be polymerized either by means of free radicals and/or cationically are used for the production of coatings, adhesives, photoresists, solder masks or in stereolithography. The mouldings produced therefrom contain a coherent, homogeneous network and have high strength properties, in particular mechanical properties.

Abstract: Photosensitive compositions comprisinga) 5-95% by weight of a polyester of formula I, II or III ##STR1## wherein R.sub.1 is the radical of a cyclic anhydride of a dicarboxylic acid after removal of the --O--CO--O-- grouping, which radical may be substituted by C.sub.1 -C.sub.22 alkyl, C.sub.5 -C.sub.10 cycloalkyl, C.sub.3 -C.sub.6 alkenyl, C.sub.6 -C.sub.10 aryl, halogen or C.sub.1 -C.sub.22 alkyl which is interrupted by --O-- or --CO--O--,R.sub.2 is hydrogen, unsubstituted or halogen-substituted C.sub.1 -C.sub.22 alkyl, C.sub.5 -C.sub.10 cycloalkyl, C.sub.7 -C.sub.22 aralkyl, C.sub.6 -C.sub.10 aryl or a radical --CH.sub.2 --O--R.sub.5 or --CH.sub.2 --O--CO--R.sub.5, wherein R.sub.5 is C.sub.1 -C.sub.22 alkyl, C.sub.5 -C.sub.6 cycloalkyl or C.sub.6 -C.sub.10 aryl,R.sub.3 is hydrogen, orR.sub.2 and R.sub.3, together with the linking carbon atoms, are a cyclopentylene or cyclohexylene radical,R.sub.

Abstract: A liquid photosensitive composition comprising(1) 40 to 80% by weight of a urethane (meth)acrylate having a functionality of 2 to 4 and a molecular weight (Mw) of 500 to 10,000,(2) 5 to 40% by weight of a hydroxyl group containing aliphatic or cycloaliphatic di(meth)acrylate,(3) 0 to 40% by weight of a mono(meth)acrylate or of a mono-N-vinyl compound having a Mw of not more than 500,(4) 0.1 to 10% by weight of a photoinitiator,(5) 0 to 30% by weight of an aliphatic or cycloaliphatic di(meth)acrylate which differs from (2), of an aliphatic tri(meth)acrylate or of an aromatic di- or tri(meth)acrylate, and(6) 0 to 5% by weight of customary additives, such that the proportion of components (1) to (6) together is 100% by weight.The composition is a photosensitive composition which can be polymerised by irradiation with actinic light and which is suitable for the production preferably of three-dimensional objects by the stereolithographic technique.

Abstract: The invention relates to photosensitive compositions comprisingA) from 40 to 80% by weight of at least one liquid epoxy resin having an epoxy functionality of equal to or greater than 2,B) from 0.1 to 10% by weight of at least one cationic photoinitiator for component A),C) from 5 to 40% by weight of at least one liquid cycloaliphatic or aromatic diacrylate,D) from 0 to 15% by weight of at least one liquid poly(meth-)acrylate having a (meth-)acrylate functionality of greater than 2, the proportion of component D) constituting a maximum of 50% by weight of the total (meth-)acrylate content,E) from 0.1 to 10% by weight of at least one radical photoinitiator for component C) and, where appropriate, D) andF) from 5 to 40% by weight of at least one OH-terminated polyether, polyester or polyurethane,which are especially suitable, for example, for the manufacture of photopolymerized layers, especially of three-dimensional objects.

Abstract: Photopolymerisable compositions comprising(a) a tetraacrylate of formula I or II ##STR1## wherein R.sub.1 is a hydrogen atom or methyl,X.sub.1 and X.sub.2 are each independently of the other --O-- or --CO--O--,R.sub.2 is a divalent aliphatic, cycloaliphatic or aromatic radical of a diglycidyl compound that contains no more glycidyl ether or ester groups,A is a divalent aliphatic, cycloaliphatic or aromatic radical of a diisocyanate compound that contains no more isocyanate groups,n is an integer from 1 to 8, andR.sub.3 is a tetravalent cycloaliphatic radical of a diepoxide compound that contains no more 1,2-epoxide groups at the cycloaliphatischen ring,(b) at least one liquid radically polymerisable compound that differs from component a), and(c) a radical photoinitiator, are suitable preferably for the production of three-dimensional objects by the stereolithographic technique.