Method of making a gas phase permeable filter

Claim 1

The method of making an odor removing thin bed filter comprising the steps: (1) providing a self supporting perforated sheet-like substrate having opposite faces and discrete perforations extending through the substrate and opening through the faces with the substrate having a width substantially equal to the width of the filters to be formed and a length sufficient to form several filters; (2) cutting such substrate into successive equal lengths, each substantially equal to the length of each filter to be formed; (3) depositing the cut lengths successively on a moving conveyor belt with one face disposed upwardly and the other lying on the belt to transport the cut lengths through a series of work performing stations; (4) at a first station, roll-coating the upwardly disposed face of each of the successive lengths of substrate with an adhesive without seepage of the adhesive through the perforations to the other face; (5) at a second station, tackifying the adhesive coating sufficiently to prevent any appreciable capillation into the odor removing particles to be subsequently applied; (6) at a third station and before the adhesive hardens preventing odor removing particles from settling into it, applying a uniform layer of such particles ranging in size from approximately 12/28 to 4/6 measured by the Tyler screen series to the upwardly disposed face of the substrate on top of the tackified adhesive coating with the particles settling into the coating; (7) while continuing to transport the cut lengths on the conveyor, curing the adhesive to a condition retaining the particles; (8) removing the successive lengths of coated substrates from the conveyor and removing unadhered particles therefrom; (9) assembling two such coated substrates with the coated faces in opposing abutting contact; and (10) securing a peripheral frame around and to the thus assembled pair of substrates to integrate them into a filter structure.

Claim 2

The method of making an odor removing thin bed filter comprising the steps: (1) providing a self supporting perforated sheet-like substrate having opposite faces and discrete perforations extending through the substrate and opening through the faces with the substrate having a width substantially equal to the width of the filters to be formed and a length sufficient to form several filters; (2) cutting such substrate into successive equal lengths, each substantially equal to the length of each filter to be formed; (3) depositing the cut lengths successively on a moving conveyor belt with one face disposed upwardly and the other lying on the belt to transport the cut lengths through a series of work performing stations; (4) at a first station, roll-coating the upwardly disposed face of each of the successive lengths of substrate with an adhesive without seepage of the adhesive through the perforations to the other face; (5) at a second station, tackifying the adhesive coating sufficiently to prevent any appreciable capillation into the odor removing particles to be subsequently applied; (6) at a third station and before the adhesive hardens preventing odor removing particles from settling into it, applying a uniform layer of such particles ranging in size from approximately 12/28 to 4/6 measured by the Tyler screen series to the upwardly disposed face of the substrate on top of the tackified adhesive coating with the particles settling into the coating; (7) while continuing to transport the cut lengths on the conveyor, curing the adhesive to a condition retaining the particles; (8) removing the successive lengths of coated substrates from the conveyor and removing unadhered particles therefrom; (9) assembling two such coated substrates with the coated faces in opposing abutting contact; and (10) securing a peripheral frame around and to the thus assembled pair of substrates to integrate them into a filter structure.