# US 2018/0001242 A1 · Biological Fluid Filters Having Flexible Walls and Methods for Making Such Filters > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0001242 A1 - Document ID: US20180001242A1 - Status: Published application - Kind: A1 - Application number: 15/702,396 - Filed: 2017-09-12 - Published: 2018-01-04 - Earliest claimed: 2014-03-24 - Assignees: Fenwal, Inc. - Applicants: Fenwal, Inc. - Inventors: Daniel Lynn; Scott Day; Paolo Verri - Web page: https://patentgrep.com/patent/US20180001242A1 ## CPC - B01D 35/30: Filter housing constructions - A61M 1/0218: {with filters} - A61M 1/0281: {Apparatus for treatment of blood or blood constituents prior to transfusion, e.g. washing, filtering or thawing} - A61M 1/34: Filtering material out of the blood by passing it through a membrane, i.e. hemofiltration or diafiltration - A61M 1/3403: {Regulation parameters} - A61M 1/3406: {Physical characteristics of the filtrate, e.g. urea} - A61M 1/3633: {Blood component filters, e.g. leukocyte filters} - A61M 1/3636: {having a flexible housing} - B01D 29/50: with multiple filtering elements, characterised by their mutual disposition (B01D29/39 takes precedence) - B01D 39/083: {of organic material} - B01D 39/086: {of inorganic material} - B01D 39/10: Filter screens essentially made of metal - B01D 39/1623: {of synthetic origin} - B01D 2201/306: Closures, lids, caps or filter heads forming one element with the filtering element - B01D 2239/1258: Permeability - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - A61M: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY (introducing media into or onto the bodies of animals A61D7/00; means for inserting tampons A61F13/26; devices for administering food or medicines orally A61J; containers for collecting, storing or administering blood or medical fluids A61J1/05); DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY (surgery A61B; chemical aspects of surgical articles A61L); DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR {(Electrotherapy, e.g. producing anaesthesia by the use of alternating or intermittent currents A61N1/36021)} ## Abstract Flexible housing filters for filtration of fluids and methods of making such filters are disclosed. The filters may include one or more peripheral seals in the flexible housing. ## Claims ### Claim at position 1 -23. (canceled) ### Claim 24 A filter assembly for removing leukocytes from blood comprising: a) a housing having first and second flexible housing walls wherein one of said housing walls comprises an inlet housing wall associated with an inlet port and said other of said housing walls comprises an outlet housing wall associated with an outlet port; b) a filter medium disposed between said housing walls, said filter medium comprising, in the direction of flow, at least first, second and third filter elements wherein: (i) said first filter element comprises a material suitable for removing a component or particulate of a biological fluid and is disposed between said inlet housing wall and said second element; (ii) said second filter element comprises a material suitable for removing another component of said biological fluid and is disposed between said first filter element and said third filter element; and (iii) said third filter element comprises an organic or inorganic material disposed between said outlet housing wall and said second filter element, said third filter element comprising a central, porous, mesh portion; and c) an outer peripheral seal and at least one inner peripheral seal separated from said outer peripheral seal by a first space, said at least one inner seal comprising a plurality of layers including: (i) a first layer at least substantially comprised of the material of said inlet housing wall; (ii) a second layer adjacent to said first layer and comprising a composite of said material of said inlet housing wall and said first and second filter element materials; (iii) a third layer adjacent to said second layer and a fourth layer, said third layer substantially comprised of said material of said second filter element; and (iv) said fourth layer being adjacent to said third layer and said outlet housing wall, said fourth layer comprising a material that is a composite of said material of said outlet housing wall and said third filter element material. ### Claim 25 (depends on 24) The filter assembly of claim 24 wherein said outer peripheral seal comprises a seal joining only said inlet housing wall and said outlet housing wall. ### Claim 26 (depends on 24) The filter assembly of claim 24 wherein said outer peripheral seal joins said first and second housing walls and at least one of said first, second and third filter elements. ### Claim 27 (depends on 24) The filter assembly of claim 24 wherein said at least one inner peripheral seal comprises a first inner peripheral seal and a second inner peripheral seal separated from said first inner peripheral seal by a second space. ### Claim 28 (depends on 27) The filter assembly of claim 27 wherein the first or second space is 1-10 mm. ### Claim 29 (depends on 24) The filter assembly of claim 24 wherein said at least one inner peripheral seal comprises a central section between peripheral sections. ### Claim 30 (depends on 24) The filter assembly of claim 24 wherein said at least one inner peripheral seal has a post-seal thickness of approximately 0.762-2.286 mm. ### Claim 31 (depends on 24) The filter assembly of claim 24 further comprising a fifth layer adjacent to said fourth layer, wherein said fifth layer is at least substantially comprised of the material of said outlet housing wall. ### Claim 32 (depends on 24) The filter assembly of claim 24 wherein said first layer has a post-seal thickness of approximately 0.076-0.381 mm. ### Claim 33 (depends on 24) The filter assembly of claim 24 wherein said second layer has a post-seal thickness of approximately 0.1-0.5 mm. ### Claim 34 (depends on 24) The filter assembly of claim 24 wherein said third layer has a post seal thickness of approximately 0.508-1.27 mm. ### Claim 35 (depends on 24) The filter assembly of claim 24 wherein said fourth layer has a post-seal thickness of less than approximately 0.15 mm. ### Claim 36 (depends on 35) The filter assembly of claim 35 wherein said fourth layer has a post-seal thickness of approximately 0.001-0.12 mm. ### Claim 37 (depends on 31) The filter assembly of claim 31 wherein said fifth layer has a post-seal thickness of approximately 0.254-0.406 mm. ### Claim 38 (depends on 24) The filter assembly of claim 24 wherein said third filter element is made at least substantially of polyvinyl chloride. ### Claim 39 (depends on 24) The filter assembly of claim 24 wherein said filter medium comprises a plurality of stacked sheets of said first, second and third filter elements. ### Claim 40 (depends on 24) The filter assembly of claim 24 wherein said first and second filter elements are made of a material selected from the group consisting of polybutylene terephthalate, polyethylene terephthalate and polypropylene. ### Claim 41 (depends on 24) The filter assembly of claim 24 wherein said fourth layer comprises polyvinyl chloride. ### Claim 42 (depends on 24) The filter assembly of claim 24 wherein said third filter element comprises polyvinyl chloride. ### Claim 43 (depends on 24) The filter assembly of claim 24 wherein said third filter element further comprises an outer peripheral, non-porous frame integral with and comprising the same material as said central, porous mesh portion. ### Claim 44 (depends on 43) The filter assembly of claim 43 wherein at least a portion of said peripheral, non-porous frame is captured within said at least one inner peripheral seal. ### Claim 45 (depends on 24) The filter assembly of claim 24 wherein said third filter element comprises a mesh sheet and a portion of said mesh sheet is captured within said at least one inner peripheral seal.