A stamp booklet is said to be exploded when it has been separated into its various components for purposes of display. This usually refers to booklets held together by staples. Modern glued booklets usually cannot be exploded without damaging the individual booklet panes.
showing the parts of something separated but in positions that show their correct relation to one another; "the manufacturer provided an exploded view of the apparatus"
A stamp booklet that has been separated into its various components, usually for purposes of display. Panes are removed intact: individual stamps are not separated from the pane.
something that's gone out of fashion was said to be "exploded."