What Disney images are not copyrighted?

I'm curious, are there any Disney images that are not protected by copyright? I've always assumed that the company's vast collection of characters, stories, and illustrations were all rigorously safeguarded by intellectual property laws. But perhaps there are instances where Disney's hold on these images is not absolute. Could you elaborate on any specific Disney images or elements that might fall outside the scope of their copyright protections? It would be fascinating to learn about any exceptions or nuances in this area.