Composite filter media

A filter comprising:

• a pleated composite filter media;
• said pleated composite filter media including a fibrous filtration layer of randomly oriented glass fibers bonded together at their points of intersection;
• said fibrous filtration layer comprising an air laid blanket of glass fibers having an average mean diameter between 3.0.times.10.sup.-5 inches and 11.0.times.10.sup.-5 inches;
• said fibrous filtration layer having an initial pressure drop no greater than about 0.30 inches of water;
• said fibrous filtration layer having an average filtration efficiency of at least 20%;
• said fibrous filtration layer having a dust holding capacity of at least 6 grams;
• and said fibrous filtration layer lacking sufficient formability and stiffness in of itself to be scored and reformed into a pleated configuration and to retain said pleated configuration;
• pleatable, permeable stiffening layer means;
• said stiffening layer means comprising a first pleatable, permeable stiffening layer having sufficient ductility and stiffness to be reformed into a pleated configuration and to retain said pleated configuration;
• a flexible, permeable covering layer for blocking a loss of fibers from said fibrous filtration layer during passage of a fluid through said pleated composite filter media;
• and
• said fibrous filtration layers said stiffening layer means, and said covering layer being bonded together with said fibrous filtration layer intermediate said first pleatable stiffening layer and said covering layer;
• and said composite filter media in of itself having sufficient formability and stiffness to be reformed into a pleated configuration and retain said pleated configuration.