build materials for 3D printing applications are described herein which, in some embodiments, comprise monomeric species operable for producing articles with high T.sub.g and/or high heat deflection temperature while maintaining shelf stability. In one aspect, a polymerizable liquid comprises at least 20 weight percent isocyanurate polyacrylate; a photoinitiator component; and a crystallization inhibitor component comprising monomeric curable material, oligomeric curable material or mixtures thereof, wherein the polymerizable liquid does not exhibit crystallization over a period of 28 days at a storage temperature of 5-10° C.

In one aspect, inks for use with a three-dimensional (3D) printing system are described herein. In some embodiments, an ink described herein comprises up to 80 wt. % oligomeric curable material; up to 80 wt. % monomeric curable material; up to 10 wt. % photoinitiator; up to 1 wt. % non-curable absorber material; and up to 10 wt. % one or more additional components, based on the total weight of the ink, and wherein the total amount of the foregoing components is equal to 100 wt. %. Additionally, the photoinitiator is operable to initiate curing of the oligomeric curable material and/or the monomeric curable material when the photoinitiator is exposed to incident curing radiation having a peak wavelength λ. Moreover, the ink has a penetration depth (D.sub.p), a critical energy (E.sub.c), and a print through depth (D.sub.PT) at the wavelength λ of less than or equal to 2×D.sub.p.

In one aspect, inks for use with a three-dimensional (3D) printing system are described herein. In some embodiments, an ink described herein comprises up to 80 wt. % oligomeric curable material; up to 80 wt. % monomeric curable material; up to 10 wt. % photoinitiator; up to 1 wt. % non-curable absorber material; and up to 10 wt. % one or more additional components, based on the total weight of the ink, and wherein the total amount of the foregoing components is equal to 100 wt. %. Additionally, the photoinitiator is operable to initiate curing of the oligomeric curable material and/or the monomeric curable material when the photoinitiator is exposed to incident curing radiation having a peak wavelength λ. Moreover, the ink has a penetration depth (D.sub.p), a critical energy (E.sub.c), and a print through depth (D.sub.PT) at the wavelength λ of less than or equal to 2×D.sub.p.

In one aspect, urethane waxes are described herein comprising a reaction product between monofunctional polyethylene oxide and polyisocyanate. In some embodiments, the urethane waxes are combined with other components to provide support materials for use in three-dimensional printing applications. A support material ink, for example, comprises a urethane wax comprising a reaction product between monofunctional polyethylene oxide and polyisocyanate. The support material ink, in some embodiments, further comprises monomeric curable material, oligomeric curable material, or mixtures thereof.

A dielectric ink composition includes an epoxy precursor and a photoacid generator. The dielectric ink composition is aerosolable and ultraviolet (UV) curable.

A dielectric ink composition includes an epoxy precursor and a photoacid generator. The dielectric ink composition is aerosolable and ultraviolet (UV) curable.

A method of fabricating a three-dimensional (3D) object includes atomizing a pre-polymer composition into an aerosol jet stream. The pre-polymer composition includes an epoxy precursor and a photoacid generator. The method further includes depositing the aerosol jet stream onto a substrate to form a first layer of dielectric ink and curing the first layer of dielectric ink using ultraviolet (UV) light. The method further includes depositing the aerosol jet stream onto the first layer of dielectric ink to form a second layer of dielectric ink. The first layer of dielectric ink and the second layer of dielectric ink overlap by at least 50%.

A method of fabricating a three-dimensional (3D) object includes atomizing a pre-polymer composition into an aerosol jet stream. The pre-polymer composition includes an epoxy precursor and a photoacid generator. The method further includes depositing the aerosol jet stream onto a substrate to form a first layer of dielectric ink and curing the first layer of dielectric ink using ultraviolet (UV) light. The method further includes depositing the aerosol jet stream onto the first layer of dielectric ink to form a second layer of dielectric ink. The first layer of dielectric ink and the second layer of dielectric ink overlap by at least 50%.

An active energy ray curing composition can be applied to cured matter of a first active energy ray curing composition. The active energy ray curing composition contains a second active energy ray curing composition containing a monofunctional monomer, a polyfunctional monomer, and a photopolymerization initiator. The proportion of the polyfunctional monomer to the second active energy ray composition is 60 percent by mass or more. The proportion of the polyfunctional monomer modified with the same number of an oxyalkylene group as the number of functional groups of the polyfunctional monomer is 90 percent by mass of the polyfunctional monomer, and the proportion of a tri- or higher polyfunctional monomer is 50 percent by mass or more to the modified polyfunctional monomer.

An active energy ray curing composition can be applied to cured matter of a first active energy ray curing composition. The active energy ray curing composition contains a second active energy ray curing composition containing a monofunctional monomer, a polyfunctional monomer, and a photopolymerization initiator. The proportion of the polyfunctional monomer to the second active energy ray composition is 60 percent by mass or more. The proportion of the polyfunctional monomer modified with the same number of an oxyalkylene group as the number of functional groups of the polyfunctional monomer is 90 percent by mass of the polyfunctional monomer, and the proportion of a tri- or higher polyfunctional monomer is 50 percent by mass or more to the modified polyfunctional monomer.