A filter arrangement

Claim 2

A filter arrangement comprising a porous support layer which has first and second surfaces, a porous filter layer which is positioned near the first surface of the porous support layer, and a plurality of polymeric beads which are disposed in parallel strips on the second surface of the porous support layer, the filter arrangement being corru­gated to define pleats extending generally perpen­dicular to the polymeric beads wherein each pleat includes an open end, a bight end, and first and sec­ond opposing sides with a portion of the opposing sides within each pleat being in essentially parallel relationship, and wherein each bead extends from the open end of the pleat along the first side to the bight end and from the bight end of the pleat along the second side to the open end, the portions of each bead which extend along the essentially parallel portions of the opposing sides of the pleat being joined to one another.

Claim 3

The filter arrangement of claim 1 wherein the porous support layer principally comprises cellu­lose fibers.

Claim 4

The filter arrangement of claim 1 wherein the porous support layer comprises a nonwoven web of fibers.

Claim 5

The filter arrangement of claim 1 wherein the porous support layer has a larger rated pore size than the porous filter layer.

Claim 6

The filter arrangement of claim 1 wherein the first and second surfaces of the porous support layer respectively comprise upstream and downstream surfaces.

Claim 7

The filter arrangement of claim 1 wherein the porous filter layer principally comprises cel­lulose fibers.

Claim 8

The filter arrangement of claim 1 wherein the porous filter layer consists essentially of glass fibers and a resin binder.

Claim 9

The filter arrangement of claim 1 wherein the rated pore size of the porous filter layer is no greater than 50 microns.

Claim 10

The filter arrangement of claim 1 wherein the porous filter layer has a first surface disposed immediately adjacent to the first surface of the po­rous support layer.

Claim 11

The filter arrangement of claim 1 wherein each bead comprises a continuous strip.

Claim 12

The filter arrangement of claim 1 wherein each bead is formed from a material which comprises a polyamide.

Claim 13

The filter arrangement of claim 1 wherein each bead is joined to the second surface of the po­rous support layer.

Claim 14

The filter arrangement of claim 1 wherein each bead has a generally circular cross section.

Claim 15

The filter arrangement of claim 1 wherein the bead portions are fused to one another.

Claim 16

A filter arrangement for removing one or more substances from a fluid flowing through the fil­ter arrangement, the filter arrangement comprising a layer of a porous filter medium which principally includes cellulose fibers and further includes glass fibers, polyester fibers, and a resin binder, the porous filter layer having a downstream surface, a layer of a porous support medium which principally includes cellulose fibers and has a rated pore size greater than the rated pore size of the porous filter layer, the porous support layer having an upstream surface and a downstream surface, the upstream sur­face of the porous support layer lying adjacent to the downstream surface of the porous filter layer, and a plurality of polyamide beads which are disposed in continuous, parallel strips on the downstream sur­face of the porous support layer, the filter arrange­ment being corrugated to define pleats extending generally perpendicular to the polymeric beads where­in each pleat includes an open end, a bight end, and first and second opposing sides with a portion of the opposing sides within each pleat being in essentially parallel relationship, and wherein each bead extends from the open end of the pleat along the first side to the bight end and from the bight end of the pleat along the second side to the open end, the portions of each bead which extend along the parallel portions of the opposing sides of the pleat being fused to one another.

Claim 17

A filter arrangement for removing one or more substances from a fluid flowing through the fil­ter arrangement, the filter arrangement comprising a layer of a porous filter medium which principally includes cellulose fibers and further includes glass fibers, polyester fibers, and a resin binder, the porous filter layer having a downstream surface, a layer of a porous support medium which principally includes cellulose fibers and has a rated pore size greater than the rated pore size of the porous filter layer, the porous support layer having an upstream surface and a downstream surface, the upstream sur­face of the porous support layer lying adjacent to the downstream surface of the porous filter layer, and a plurality of polyamide beads which are disposed in continuous, parallel strips on the downstream sur­face of the porous support layer, the filter arrange­ment being corrugated to define pleats extending generally perpendicular to the polymeric beads where­in each pleat includes an open end, a bight end, and first and second opposing sides with a portion of the opposing sides within each pleat being in essentially parallel relationship, and wherein each bead extends from the open end of the pleat along the first side to the bight end and from the bight end of the pleat along the second side to the open end, the portions of each bead which extend along the parallel portions of the opposing sides of the pleat being fused to one another.

Claim 18

The filter arrangement of claim 15 wherein the porous filter layer has a rated pore size in the range from about 3 to about 25 microns.

Claim 19

A filter arrangement for removing one or more substances from a fluid flowing through the fil­ter arrangement, the filter arrangement comprising a layer of a porous filter medium which consists essen­tially of glass fibers and a resin binder, the porous filter layer having a downstream surface, a layer of a porous support medium which principally includes cellulose fibers and has a rated pore size greater than the rated pore size of the porous filter layer, the porous support layer having an upstream surface and a downstream surface, the upstream surface lying adjacent to the downstream surface of the porous fil­ter layer, and a plurality of polyamide beads which are disposed in continuous, parallel strips on the downstream surface of the porous support layer, the filter arrangement being corrugated to define pleats extending generally perpendicular to the polymeric beads wherein each pleat includes an open end, a bight end, and first and second opposing sides with a portion of the opposing sides within such pleats being in essentially parallel relationship and each bead extending from the open end of the pleat along the first side to the bight end and from the bight end of the pleat along the second side to the open end, the portions of each bead which extend along the parallel portions of the opposing sides of the pleat being fused to one another.

Claim 20

A filter arrangement for removing one or more substances from a fluid flowing through the fil­ter arrangement, the filter arrangement comprising a layer of a porous filter medium which consists essen­tially of glass fibers and a resin binder, the porous filter layer having a downstream surface, a layer of a porous support medium which principally includes cellulose fibers and has a rated pore size greater than the rated pore size of the porous filter layer, the porous support layer having an upstream surface and a downstream surface, the upstream surface lying adjacent to the downstream surface of the porous fil­ter layer, and a plurality of polyamide beads which are disposed in continuous, parallel strips on the downstream surface of the porous support layer, the filter arrangement being corrugated to define pleats extending generally perpendicular to the polymeric beads wherein each pleat includes an open end, a bight end, and first and second opposing sides with a portion of the opposing sides within such pleats being in essentially parallel relationship and each bead extending from the open end of the pleat along the first side to the bight end and from the bight end of the pleat along the second side to the open end, the portions of each bead which extend along the parallel portions of the opposing sides of the pleat being fused to one another.

Claim 21

The filter arrangement of claim 17 wherein the porous filter layer has a rated pore size in the range from about 1 to about 50 microns.