Multi-layer filter

• US 4,483,771 A
• Filed: 08/08/1983
• Issued: 11/20/1984
• Est. Priority Date: 08/08/1983
• Status: Expired due to Fees

• Current Assignee: Elizabeth Koch
• Original Assignee: Elizabeth Koch
• Inventors: Koch, Elizabeth
• Primary Examiner(s): CINTINS, IVARS C
• Application Number:
  US06/521,266
• Time in Patent Office: 470 Days
• Field of Search: 210/500.1, 210/501, 210/502.1, 210/503-509, 210/500.2, 210/483, 210/484, 210/488-492, 210/496
• US Class Current: 210/490
• CPC Class Codes: A61L 9/00 Disinfection, sterilisation or deodorisation of air body deodorants A61Q15/00; purifying air by respirators A62B, A62D9/00; separating dispersed particles from gases or vapours B01D45/00 - B01D51/00, B03C3/00; chemical or biological purification of waste gases B01D53/34; production of ozone C01B13/10; air-conditioning systems incorporating sterilisation F24F3/16, F24F8/20
• CPC Class Codes: B01D 2325/48 Antimicrobial properties
• CPC Class Codes: B01D 35/00 Filtering devices having features not specifically covered by groups B01D24/00 - B01D33/00, or for applications not specifically covered by groups B01D24/00 - B01D33/00; Auxiliary devices for filtration; Filter housing constructions
• CPC Class Codes: B01D 39/00 Filtering material for liquid or gaseous fluids
• CPC Class Codes: B01D 69/12 Composite membranes; Ultra-thin membranes
• CPC Class Codes: B01D 69/1218 Layers having the same chemical composition, but different properties, e.g. pore size, molecular weight or porosity
• CPC Class Codes: B01D 69/141 Heterogeneous membranes, e.g. containing dispersed material; Mixed matrix membranes

Abstract

A multi-layer filter combination having a macrofilter layer with a predetermined thickness and two major sides including porous material impregnable with bacteria-destroying medication and having pore sizes in the range from about 1 micron to about 120 microns. There is also a microfilter layer having a prearranged thickness smaller than the thickness of the macrofilter and including a porous membrane having pore sizes from about 0.1 micron to about 10 microns. The microfilter layer is mechanically bonded to at least a major side of the macrofilter layer, whereby inhibiting transfer of any remaining live bacteria which may have survived exposure to the bacteria-destroying medication, and which may attempt to pass outwardly beyond the microfilter layer. The medication is either an antibiotic and an iodophore.

Claims

1. A multilayer filter combination, comprising

a macrofilter layer having a predetermined thickness and two major sides, said macrofilter layer including porous material impregnated with bacteria-destroying medication and having pore sizes in the range from about 1 micron to about 120 microns, and

a microfilter layer having a prearranged thickness smaller than said predetermined thickness, and including a porous membrane having pore sizes from about 0.1 micron to about 10 microns, said microfilter layer being mechanically bonded to at least a major side of said macrofilter layer, whereby transfer of any remaining live bacteria which may have survived exposure to said bacteria-destroying medication, and which may attempt to pass outwardly beyond said microfilter layer is inhibited.

2. A multilayer filter combination as claimed in claim 1, wherein said bacteria-destroying medication is selected from the group consisting of antibiotics and an iodophore.

3. The multilayer filter combination as claimed in claim 2, wherein said bacteria-destroying medication is aqueous.

4. The multilayer filter combination as claimed in claim 2, wherein said bacteria-destroying medication is powdered.

5. The multilayer filter as claimed in claim 2, wherein said antibiotics are selected from a group consisting of penicillin, tetracyclene, kanamycin, and sulfonamides.

6. A multilayer filter combination as claimed in claim 1, wherein said predetermined thickness is about 0.005 inches, and wherein said porous membrane of said microfilter layer includes a unitary organic resin film having pore sizes in the range from about 0.1 microns to about 10 microns, and formed with random and irregular passages therethrough.

7. The multilayer filter as claimed in claim 1, wherein said macrofilter layer is a substrate for said microfilter layer.

8. A multilayer filter as claimed in claim 1, wherein said microfilter layer is bonded to said macrofilter layer by being coated thereon.

9. A multilayer filter as claimed in claim 1, wherein said microfilter layer completely and tightly envelops said macrofilter layer.

10. A multilayer filter as claimed in claim 1, and wherein said microfilter layer is composed of a synthetic plastic material.

11. A multilayer filter as claimed in claim 10, wherein said synthetic plastic material consists of a material selected from the group of cellulose triacetate, cellulose esters, polyvinyl chloride, copolymers of polyvinyl chloride, acrylic polymer, polytetrafluroethylene, and regenerated cellulose.

12. A multilayer filter as claimed in claim 10, wherein said synthetic plastic material consists of a material selected from the group of nylon, polyester, or any membrane forming material.

13. A multilayer filter as claimed in claim 10, wherein said synthetic plastic material consists of a material selected from the group consisting of an acetal resin and polyvinyl difluoride.

14. A multilayer filter as claimed in claim 1, wherein said macrofilter layer is composed of synthetic plastic material.

15. A multilayer filter as claimed in claim 14, wherein said synthetic plastic material is selected from the group consisting of polyethylene, polypropylene, nylon, and teflon.

16. A multilayer filter as claimed in claim 1, wherein said macrofilter layer is composed of charcoal.

17. A multilayer filter as claimed in claim 1, wherein said microfilter layer is hydrophobic.

18. A multilayer filter as claimed in claim 1, wherein said microfilter layer is hydrophilic.