Porous laminate and method of manufacture

[2. The laminate of claim 1 wherein said slot patterns comprise a parallel series of uniform width slots formed in said lamina.]

[3. The laminate of claim 1 wherein said slots formed in said lamina are tapered in the plane of the lamina and said lamina are stacked with the larger end of said slots overlapping, whereby a variable porosity laminate is provided.]

[4. The laminate of claim 1 wherein said slots in said slot patterns have spaced tie sections formed along their lengths.]

[5. The laminate of claim 1 wherein each of said lamina have solid areas formed extending around said slot patterns and wherein said solid areas as aligned in said stack, whereby said laminate is formed with a solid peripheral border.]

[6. The laminate of claim 1 wherein said slots in alternate lamina in said stack extend parallel to each other but are at least partially offset from each other to form lateral flow passages in said laminate.]

A multilayer porous laminate comprising a plurality of lamina, each lamina having a slot pattern formed therein, wherein each slot pattern comprises a series of slots formed in the corresponding lamina, said slots in a lamina defining axes of orientation parallel therebetween, said lamina being stacked in intimate contact with each other, with said slots of adjacent lamina overlaying in abutting relationship and extending with their respective axes of orientation at an angle to each other to provide intersecting slot patterns, the slots in alternate lamina in said stack having parallel axes of orientation to each other which are at least partially and laterally offset from each other to form lateral flow passages in said laminate, and means bonding said lamina to each other to form said laminate, whereby said intersecting slot patterns form fluid flow passages through said laminate.

A porous filter laminate comprising:

• a plurality of lamina having slot patterns formed therein, said lamina stacked in intimate contact with each other with said slot patterns of adjacent lamina overlapping and extending transversely to each other to provide intersecting slot patterns, said slots formed in said lamina being tapered in the plane of the lamina and said lamina being stacked with the larger end of said slots overlapping, whereby a variable porosity laminate is provided, the slots in alternate lamina in said stack having parallel axes of orientation to each other which are at least partially and laterally offset from each other, said stacked lamina being bonded to each other to form said laminate, whereby said intersecting slot patterns form fluid passages through said laminate.

A method of manufacturing a porous material, characterized by the steps of forming a series of slots in a plurality of lamina, said slots in a lamina defining axes of orientation parallel therebetween, stacking said lamina in intimate contact with each other with said slots of adjacent lamina overlaying and extending at an angle to each other, stacking said lamina with slots of alternate lamina having parallel axes of orientation which are laterally offset from each other, and bonding said lamina to each other to form a multilayer porous laminate.