It is intended to provide an optical three-dimensional object as will be
described below which has a high impact resistance and is superior in
dimensional accuracy, mechanical properties such as tensile strength, and
other properties such as water resistance, moisture resistance and heat
resistance, and a method of producing the same. An optical
three-dimensional object includes multiple cured resin layers containing
at least one cured resin layer that has a sea-island microstructure in
which fine island components of a polymer differing from a cured resin
constituting the sea component and have a particle diameter of 20 to
2,000 nm are dispersed in the sea component made of the cured polymer;
and a method of producing this optical three-dimensional object by
stereolithographic molding method with the use of a photo curable resin
composition containing a homogeneous mixture of a curable resin component
for forming the sea component with a component (preferably a polyalkylene
ether compound) for forming the polymeric island components.