The present invention provides an improved method for laminating a first three-dimensional apertured or non-apertured film material to a second flat or three-dimensional apertured or non-apertured film material utilizing the heat generated by the extrusion of the first and/or second materials...http://www.google.sh/patents/US5783014?utm_source=gb-gplus-sharePatent US5783014 - Lamination of apertured or non-apertured three-dimensional films to apertured or non-apertured three-dimensional and/or flat films 
