US5468529A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic filter material comprising a self-bonding nonwoven fabric of continuous thermoplastic fibers and magnetic particulate within the fibers
Assignee: SHIN YANG PROTECTION & PURIFICATION Ltd
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Filing: 1995-01-12
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Granted: 1995-11-21
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Expires: 2015-01-12
Abstract
Abstract A magnetic filter material is disclosed. The filter material according to the present invention comprises a spray-spun, self-bonded, nonwoven fibrous structure consisting essentially of 40 to 99% by weight of a polymer selected from the group consisting of polycarbonate, polyethylene, polypropylene, polyamide, polyimide, polyester, polytetrafluoroethylene and polyacrylonitrile and 1 to 60% by weight of a magnetic substance selected from the group consisting of barium ferrite, strontium ferrite and samarium-cobalt. The magnetic filter material of the present invention shows excellent filtration efficiency of metal impurities such as iron, iron oxides, and other metal dusts due to have a dual function by physical porosity and magnetic attraction, and thus is suitable as an air and oil filter medium for automobiles and other industrial machinery, a liquid filter medium for treating industrial waste water and oil, a filter medium in dust collecting and air-conditioning systems, and so forth.
Inventors
- 👤 Oh K. Kwon
- 👤 Ung S. Choi
- 👤 Ki Y. Choi
- 👤 N. K. Mishkin
- 👤 Yoon M. Jung
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:35
CPC Classifications
D; D04; D04H; D04H3/00; D04H3/08; D04H3/16; B; B01; B01D; B01D35/00; B01D35/06; B01D39/00; B01D39/14; B01D39/16; B01D39/1607; B01D39/1623; B03; B03C; B03C1/00; B03C1/02; B03C1/28; D01; D01F; D01F1/00; D01F1/02; D01F1/10; B03C2201/00; B03C2201/16; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10S428/903; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/1362; Y10T428/1372; Y10T442/00; Y10T442/60; Y10T442/699
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
71 words
A magnetic filter material which is made of a spray-spun planar or cylindrical, self-bonded, nonwoven structure comprising randomly arranged substantially continuous fibrous material, consisting essentially of 40 to 99% by weight of a polymer selected from the group consisting of polycarbonate, polyethylene, polypropylene, polyamide, polyimide, polyester, polytetrafluoroethylene and polyacrylonitrile and 1 to 60% by weight of a magnetic substance selected from the group consisting of barium ferrite, strontium ferrite, and samarium-cobalt.
Claim 2
Dependent Claim
71 words
A magnetic filter material which is made of a spray-spun planar or cylindrical, self-bonded, nonwoven structure comprising randomly arranged substantially continuous fibrous material, consisting essentially of 40 to 99% by weight of a polymer selected from the group consisting of polycarbonate, polyethylene, polypropylene, polyamide, polyimide, polyester, polytetrafluoroethylene and polyacrylonitrile and 1 to 60% by weight of a magnetic substance selected from the group consisting of barium ferrite, strontium ferrite, and samarium-cobalt.
Claim 3
Dependent Claim
43 words
The magnetic polymer filter material having a nonwoven fibrous structure according to claim 1, wherein the polymer is contained in an amount of 60 to 98% by weight and the magnetic substance is contained in an amount of 2 to 40% by weight.
Claim 4
Dependent Claim
144 words
The magnetic filter material according to claim 1, wherein the polycarbonate is an aromatic polycarbonate having a molecular weight of 10,000 to 30,000; the polyethylene is a high-density polyethylene having a molecular weight of 10,000 to 50,000 and a density of 0.94 to 0.96 g/cm 3 ; the polytetrafluoroethylene is polytetrafluoroethylene having a molecular weight of 500,000 to 3,000,000; the polypropylene is a polypropylene homopolymer having a molecular weight of 40,000 to 60,000 and a density of 0.94 g/cm 3 ; the polyamide is Nylon 6 having a molecular weight of 1,000 to 5,000 or Nylon 6.6 having a molecular weight of 10,000 to 40,000; the polyimide is an aromatic polyimide having a molecular weight of 10,000 to 40,000; the polyester is polyester having a molecular weight of 15,000 to 45,000; and the polyacrylonitrile is polyacrylonitrile having a molecular weight of 20,000 to 50,000.
Claim 5
Dependent Claim
144 words
The magnetic filter material according to claim 2, wherein the polycarbonate is an aromatic polycarbonate having a molecular weight of 10,000 to 30,000; the polyethylene is a high-density polyethylene having a molecular weight of 10,000 to 50,000 and a density of 0.94 to 0.96 g/cm 3 ; the polytetrafluoroethylene is polytetrafluoroethylene having a molecular weight of 500,000 to 3,000,000; the polypropylene is a polypropylene homopolymer having a molecular weight of 40,000 to 60,000 and a density of 0.94 g/cm 3 ; the polyamide is Nylon 6 having a molecular weight of 1,000 to 5,000 or Nylon 6.6 having a molecular weight of 10,000 to 40,000; the polyimide is an aromatic polyimide having a molecular weight of 10,000 to 40,000; the polyester is polyester having a molecular weight of 15,000 to 45,000; and the polyacrylonitrile is polyacrylonitrile having a molecular weight of 20,000 to 50,000.
Claim 6
Dependent Claim
108 words
The magnetic filter material according to claim 1, wherein the fibrous structure of the filter material has a composition selected from the group consisting of: 95% by weight of polyethylene and 5% by weight of strontium ferrite; 90% by weight of polypropylene and 10% by weight of strontium ferrite; 95% by weight of polyester and 5% by weight of barium ferrite; 80% by weight of polytetrafluoroethylene and 20% by weight of samarium-cobalt; 70% by weight of polyamide and 30% by weight of strontium ferrite; 80% by weight of polyimide and 20% by weight of barium ferrite; and 85% by weight of polycarbonate and 15% by weight of samarium-cobalt.
Claim 7
Dependent Claim
56 words
The magnetic filter material according to claim 1, wherein the magnetic filter material is spray spun and collected in the form of sheets or hollow cylinders, which is made of a self-bonded, nonwoven fibrous structure having a pore size of 0.1 to 200 μm and a fiber diameter of 0.01 to 1.0 mm, and then magnetized.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-11-20 | 1999-05-22 | 1999-11-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-11-20 | 2003-05-22 | 2003-11-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-11-20 | 2007-05-22 | 2007-11-21 | $7700.00 | Window Closed / Lapsed |