The method of forming pleated filter media includes providing a generally
planar web of filter material, folding the web to form a pleated web
having a plurality of fold lines, arranging the plurality of pleats in a
first spaced configuration defined by a first distance between adjacent
pleat tips, applying a continuous strand of adhesive to the web, and
adjusting the arrangement of the plurality of pleats into a second spaced
configuration defined by a second distance between adjacent pleat tips.
The web has a front face and a rear face. Each fold line is intermediate
oppositely sloping first and second wall surfaces. The plurality of fold
lines form a plurality of pleats having a first plurality of pleat tips
and a second plurality of pleat valleys. The second distance is different
from the first distance.