Properness of minimal surfaces with bounded curvature

We show that immersed minimal surfaces of ${\mathbb{R}}^3$ with bounded curvature and proper self intersections are proper. We also show that the restriction of the immersing map to a wide component is always proper. When the immersing map is injective the whole surface is a wide component. Prior to these results it was only known that injectively immersed minimal surfaces with bounded curvature were proper.