Stratasys, Inc.

The present invention relates to a method for producing an object in an additive manufacturing process from a precursor and comprises the following steps: I) depositing a layer of a radically cross-linkable construction material, which corresponds to a first selected cross-section of the precursor, on a carrier; II) depositing a layer of a radically cross-linkable construction material, which corresponds to a further selected cross-section of the precursor, on a previously applied layer of the radically cross-linked construction material; III) repeating step II) until the precursor is formed. The radically cross-linkable construction material comprises a thermoplastic radically cross-linkable polyurethane with a urethane group content of ≥5% by weight and a photoinitiator. The radically cross-linkable construction material is also heated to a processing temperature that is greater than the melting point of the radically cross-linkable polyurethane. After step III) the precursor having a temperature of 20° C. is defined as the object, or step IV) is performed: IV) performing a chemical reaction in the precursor obtained after step III) so that the object is obtained.

Provided is a photopolymerizable composition comprising a blend of: a) from 40 wt. % to 70 wt. % of at least one urethane component; b) from 25 wt. % to 70 wt % of at least one monofunctional reactive diluent; c) from 0.1 wt. % to 5 wt. % of at least one initiator; and d) from 2 wt. % to 10 wt % of an amine-functional (meth)acrylate monomer of formula (I), C═C—CO—O—R 1 —NR 2 R 3 (I); e) optionally, at least one multiple-functional reactive diluent; f) optionally, from 0.001 wt. % to 1 wt. % of an inhibitor, wherein the wt. % in all instances is based on total weight of the photopolymerizable composition, wherein at least one of R 1 , R 2 , and R 3 is an alkyl group, and wherein the amine-functional (meth)acrylate monomer is not an amide. Also provided is a process of producing a photopolymerizable composition, the process comprising blending the ingredients of the prior sentence. Further provided is a process of producing a three-dimensional object, the process comprising the steps of: A) depositing the photopolymerizable composition according to the first sentence atop a carrier to obtain a layer of a construction material joined to the carrier which corresponds to a first selected cross section of the precursor; B) depositing additional photopolymerizable composition atop a previously applied layer of the construction material to obtain a further layer of the construction material which corresponds to a further selected cross section of the precursor and which is joined to the previously applied layer, C) repeating step B) until the precursor is formed, wherein the depositing of the photopolymerizable composition at least in step B) comprises introducing energy to a selected region of the photopolymerizable composition corresponding to the respectively selected cross section of the object.

A resin comprises: A) a (meth)acrylate-functional compound; B) a polyisocyanate; C) a radical starter and D) a catalyst. The compound A) has an equivalent molecular weight with respect to (meth)acrylate C═C double bonds of ≥500 g/mol and an average number of (meth)acrylate groups per molecule of ≥1.8 to ≤2.2, the polyisocyanate B) has an average NCO group functionality of ≥2 and an equivalent molecular weight with respect to NCO groups of ≤300 g/mol, the catalyst D) is an isocyanate trimerization catalyst and the resin is free from NCO-reactive compounds or, if NCO-reactive compounds are present in the resin, the molar ratio of NCO groups to NCO-reactive groups is ≥5:1. Such resins may form hybrid polymer networks.

The invention relates to a method for producing an at least partially coated object, comprising the step of producing the object from a construction material by means of an additive manufacturing method, the construction material comprising a thermoplastic polyurethane material. Following the production of the object, the method comprises the step of at least partially bringing a preparation into contact with the object, the preparation being selected from: an aqueous polyurethane dispersion; an aqueous dispersion of a polymer comprising OH groups, this dispersion also containing a compound comprising NCO groups; an aqueous preparation of a compound containing NCO groups, but not containing any polymers comprising OH groups; or a combination of at least two thereof. The invention also relates to an at least partially coated object that was obtained by a method according to the invention.

The invention relates to a method for producing a polymer comprising the following steps: (A) depositing a radically cross-linkable resin, obtaining a radically cross-linked resin; and (B) treating the radically cross-linked resin under conditions which are sufficient to trigger a chemical reaction that is different from the radical cross-linking in the radically cross-linked resin. The radically cross-linkable resin comprises a curable component, in which there are NCO groups, olefinic C═C double bonds and epoxide groups, and the chemical reaction in the radically cross-linked resin that is different from the radical cross-linking is the reaction of NCO groups and epoxide groups to form oxazolidinone groups.

Provided is a photopolymerizable composition comprising a blend of: a) from 40 wt. % to 70 wt. % of at least one urethane component; b) from 25 wt. % to 70 wt % of at least one monofunctional reactive diluent; c) from 0.1 wt. % to 5 wt. % of at least one initiator; and d) from 2 wt. % to 10 wt % of an amine-functional (meth)acrylate monomer. Also provided is a process of producing a photopolymerizable composition by blending these ingredients. Further provided is a process of producing a three-dimensional object, by depositing the photopolymerizable composition atop a carrier; depositing additional photopolymerizable composition atop a previously applied layer wherein the depositing of the photopolymerizable composition comprises introducing energy.