Abstract: An odor-removing filter approaching the carbon-particle loading of a filled filter may be formed by spraying or roll coating the adhesive against one or more faces of a porous, fibrous, air-permeable mat, depositing carbon particles or other odor-removing particles of a size to compliment the void size of the mat on the adhesive coated face or faces of the mat and then driving the particles into the mat and thereafter curing the adhesive to lock the particles into the mat. The adhesive bond of the particles to the mat is improved by working the particles against the adhesive-coated fibers. An overspray of an adhesive may also be utilized to further improve the retention of the particles. So-called "clean filters" may be produced according to the method disclosed, wherein a white, fibrous mat has carbon particles loaded on one face while the opposite face appears white or "clean". An indicator filter notifying the user when the filter becomes grease laden may also be formed following the methods used herein.