This one’s my favorite, so I saved it for last. The ability to overprint colors on multiple passes is one of the most exciting features of the screen printing process that digital designers often utilize transparency to recreate.
The interplay of line, shape, color, and texture is really on exhibition in these examples, and the equal focus of image and text adds a depth that comes through in the instability of the background/foreground relationships.
So before you use transparency in a design project, consider why you are using it. And keep in mind that “no substance is wholly transparent, and no material absolutely opaque.”