Led curable liquid resin compositions for additive fabrication

A photocurable resin composition for additive fabrication comprising a polymerizable component that is polymerizable by free-radical polymerization, cationic polymerization, or both free-radical polymerization and cationic polymerization, and a photoinitiating system capable of initiating the free-radical polymerization, cationic polymerization, or both free-radical polymerization and cationic polymerization;

• wherein the photocurable resin composition is a liquid at about 25° C., and is capable of curing to provide a solid upon irradiation with light emitted from a light emitting
• diode (LED), wherein the light has a wavelength of from about 100 nm to about 900 nm, preferably from 200 nm to about 600 nm, more preferably from about 280 nm to about 500 nm, more preferably from about 300 nm to about 475 nm, more preferably from about 340 nm to about 415 nm, preferably having a peak at about 365 nm, and
• wherein the liquid photocurable resin composition has a Critical Exposure (Ec) and a Depth of Penetration (Dp) as measured on a layer of the photocurable resin composition as the composition is curing, wherein Ec is from about 0.01 seconds to about 6.0 seconds and Dp is ¼ to 4 times, preferably from ⅓ to 3 times, the thickness of the layer.