Filter element formed of pleated paper

Claim 1

IN A PROCESS FOR THE MANUFACTURE OF PLEATED PAPER FILTER ELEMENTS WHICH INCLUDES THE STEPS OF FOLDING A RESIN IMPREGNATED PAPER STRIP INTO A MULTIPLICITY OF PLEATS HEATING THE PLEATED STRIP FOR A TIME AND A TEMPERATURE SUFFICIENT TO AT LEAST PARTIALLY CURE THE RESIN THEREBY SETTING THE PLEATS AND STIFFENING THE PAPER AND THEREAFTER FORMING THE PLEATED AND CURED STRIP INTO CYLINDRICAL FILTER ELEMENTS WITH THE PLEATS EXTENDING PARALLEL TO THE PRINCIPAL AXIS OF THE CYLINDER, THE PROCESS OF REINFORCING THE PLEATS AGAINST COLLAPSE WHEN THE PLEATED FILTER ELEMENT IS USED AS A FILTER WHICH COMPRISES PROVIDING A PLURALITY OF RELATIVELY HARD AND NON-DEFORMABLE SPHERICAL BEAD-LIKE UNITS SAID UNITS HAVING AT LEAST A SURFACE THAT BECOMES ADHESIVE UPON BEING HEATED TO THE TEMPERATURE TO WHICH THE PAPER STRIP IS HEATED AND SAID UNITS BETWEEN EACH SUCCESSTHAT IS SUBSTANTIAL RELATIVE TO THE SPACING OF THE PLEATS, INSERTING AT LEAST ONE OF SAID UNITS BETWEEN EACH SUCESSSIVE PLEAT ON ONE SIDE OF PAPER STRIP AFTER THE PLEAT HAS BEEN FORMED IN SAID PAPER STRIP AN D BEFORE THE STRIP HAS BEEN HEATED TO CURE THE RESIN CONTAINED THEREIN WHEREBY WHEN THE STRIP IS HEATED EACH OF SAID UNITS WILL ADHESIVELY SECURED TO THE SIDES OF THE PLEAT IN WHICH IT IS INSERTED AND THEREBY REINFORCE SAID PLEAT AGAINST COLLAPSE.