A process for forming a three-dimensional object comprises repeatedly imagewise exposing the surface of a reservoir of liquid photohardenable composition, curable by actinic radiation, with actinic radiation to harden the liquid composition near the surface to form a plurality of superimposed layers of hardened composition. In this invention, the liquid photohardenable composition consists essentially of:
(a) 25 to 65% of a difunctional acrylated polyurethane oligomer or a mixture of the oligomers;
(b) 15 to 65% of a polyglycol ester of the following formula:
wherein:
R is hydrogen or methyl, and
n is an integer from 2 to 5;
or a mixture of the polyglycol esters;
(c) 0.1 to 10% of a photoinitiator system sensitive to the actinic radiation or a mixture of the photoinitiator systems; and
(d) 0 to 30% of a polyfunctional reactive diluent or a mixture of the reactive diluents;
wherein the liquid photohardenable composition has a viscosity of 200 to 8000 cP at 25 °C.
一种用于形成三维物体的工艺,包括反复对可通过光辐射固化的液态光硬化组合物的储液器表面进行图像曝光,用光辐射使液态组合物在表面附近硬化,以形成多层叠加的硬化组合物。在本发明中,液态光硬化组合物主要包括:
(a) 25-65%的双官能团
丙烯酸聚
氨酯低聚物或低聚物混合物;
(b) 15-65%的下式聚
乙二醇酯:
其中
R 是氢或甲基,以及
n 是 2 至 5 的整数;
或聚
乙二醇酯的混合物;
(c) 0.1%至 10%对光辐射敏感的光
引发剂体系或光
引发剂体系的混合物;以及
(d) 0 至 30%的多官能团活性稀释剂或活性稀释剂的混合物;
其中液态光硬化组合物在 25℃时的粘度为 200 至 8000cP。