Method of forming self-supporting pleated filter media

A method of forming pleated filter media comprising:

• providing a generally planar web of nonwoven polymeric material, the web having a front face and a rear face, wherein the web further comprises a pair of opposite side edges and a pair of opposite end edges;
• scoring the web at regularly spaced intervals;
• folding the web to form a pleated web having a plurality of fold lines, each fold line being intermediate oppositely sloping first and second wall surfaces, wherein the plurality of fold lines form a plurality of pleats-having a first plurality of pleat tips and a second plurality of pleat valleys;
• heat setting the plurality of pleats;
• arranging the plurality of pleats in a first spaced configuration defined by a first distance between adjacent pleat tips;
• applying a plurality of parallel, continuous strands of adhesive to the web so that each strand of adhesive contacts the web at a pleat tip, contacts the web at a portion of a wall surface, and does not contact the web in a valley, wherein a strand is spaced from an adjacent strand by between about 2.5 cm and about 12.7 cm;
• adjusting the arrangement of the plurality of pleats into a second spaced configuration defined by a second distance between adjacent pleat tips, the second distance being different from the first distance, wherein the second distance is between about 1.8 mm and about 12.6 mm;
• adhering a metal mesh scrim to the rear face of the web;
• and
• applying a frame member at each edge, wherein each frame member covers an edge and at least a portion of each of the front face and the rear face.