Abstract: The present disclosure relates to the use of occluding fluids, such as a high-density fluid (a “z-fluid”) or a low-density fluid (an “a-fluid”), to displace resin within a vat during 3D printing. Further, an a-fluid may act as a protective boundary for a 3D printing resin wherein the a-fluid sits on top of the printing resin. Another embodiment of the disclosure provides a process of assessing which regions of a computer-aided design (CAD) model take advantage of a buoying force supplied by the occluding fluid, such that fewer support structures are needed for printing a final CAD model compared to printing the CAD model without the occluding fluid.

Abstract: The present disclosure relates to sealed isocyanate resin compositions. The resin compositions may be used for additive manufacturing. One embodiment of the invention includes a photopolymerizable resin for additive manufacturing, the resin comprising: a blocked isocyanate; at least one monomer or oligomer; and a multifunctional nucleophile.

Abstract: The present disclosure relates to sealed isocyanate resin compositions. The resin compositions may be used for additive manufacturing. One embodiment of the invention includes a photopolymerizable resin for additive manufacturing, the resin comprising: a blocked isocyanate; at least one monomer or oligomer; and a multifunctional nucleophile.

Abstract: The present disclosure relates to sealed isocyanate resin compositions. The resin compositions may be used for additive manufacturing. One embodiment of the invention includes a photopolymerizable resin for additive manufacturing, the resin comprising: a blocked isocyanate; at least one monomer or oligomer; and a multifunctional nucleophile.

Abstract: A method of three-dimensional stereolithography printing a thiourethane polymer part using the vat resin. Adding a resin to a vat of a three-dimensional stereolithography printer, the resin a liquid mixture including: a first type of monomer including two or more thiol functional groups, a second type of monomer including two or more isocyanate functional groups, a photolatent base, an anionic step-growth polymerization reaction inhibitor and a light absorber. The photolatent base is decomposable upon exposure to a light to form a non-nucleophillic base catalyst having a pKa greater than 7. The anionic step-growth polymerization reaction inhibitor has an acidic group configured to form an acid-base pair with the non-nucleophillic base. The light absorber has an absorbance in the liquid mixture that is greater than an absorbance of the photolatent base at a wavelength of the light used for the exposure.

Abstract: A vat resin for three-dimensional stereolithography printing of a thiourethane polymer part comprising a liquid mixture including a first type of monomer, a second type of monomer, a photolatent base decomposable upon exposure to a light to form a non-nucleophillic base catalyst having a pKa greater than 7, an anionic step-growth polymerization reaction inhibitor having an acidic group configured to form an acid-base pair with the non-nucleophillic base and a light absorber having an absorbance in the liquid mixture that is greater than an absorbance of the photolatent base at a wavelength of the light used for the exposure. Methods of preparing the vat resin and three-dimensional stereolithography printing a thiourethane polymer part using the vat resin are also disclosed.

Abstract: A semi-crystalline thiourethane polymer. The semi-crystalline thiourethane polymer comprises a sequential chain of a first type of monomer covalently bonded to a second type of monomer via thiourethane linkages. Each of the first type of monomer includes two or more thiol functional groups and each of the second type of monomer includes two or more isocyanate functional groups. The first and second types of monomers are polymerized together in an anionic step-growth polymerization reaction that is catalyzed by a non-nucleophillic base having a pKa greater than 7, produced by photo-initiated decomposition of a photolatent base. A method of synthesizing, and polymer jetting and stereolithography methods of manufacturing a polymer part, are also disclosed.