These paintings (and one drawing) were locked in storage after Cobain's death. Courtney Love recently unveiled them for auction. They were painted in 1993, during the recording of Nirvana's last album In Utero, and at the height of Kurt's drug addiction.
Artist Christian Marclay mixed together record sleeves to create these and other collages in a series called "Body Mix." He did all this in 1991, way before you kids got so crazy about vinyl sleeve heads, also get off my lawn thankyouverymuch.