I have seen something similar done for adding labels to 3d-printed cases or to label control panels that were printed. Archive: https://archive.today/Tjg1K From the post: >>We’ve always found the various methods for adding text and graphics to 3D prints somewhat underwhelming. Embossed or debossed characters are fuzzy, at best, and multi-color printers always seem to bleed one color into the next. Still, the need for labels and logos is common enough that it’s worth exploring other methods, such as this easy toner transfer trick.