Patent ID: 7029265

Claim:
An apparatus for producing plastic panels which are provided on at least one side with at least one integral undercut attachment, wherein said apparatus comprises: an extruder, a die, and at least one roll nip formed by at least two rolls, wherein the die and the at least one roll nip cooperate so that molten polymer can be fed through said die to said at least one roll nip, wherein at least one of said rolls of said roll nip is provided on the roll circumference with at least one mold which corresponds to said undercut attachment, wherein the at least one mold is provided in at least one molding/demolding strip, wherein said molding/demolding strip has a first non-raised position and a second raised position and wherein the molding/demolding strip is capable of assuming said second position to nondestructively release the at least one undercut attachment of the plastic panel after the at least one undercut attachment has left the at least one roll nip.