Patent EP0395331A1 successfully refreshed from Google Patents.
EP0395331A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Electret filter material
Assignee: Japan Gore Tex Inc
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Filing: 1990-04-23
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Granted: —
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Expires: 2010-04-23
Abstract
Abstract A composite filter material for filtering gases comprising at least one layer of porous polytetrafluoroethylene and at least one layer of fibrous electret material for use to clean the air in facilities such as clean rooms for manufacturing semiconductors, electronic equipment, or medical products.
Inventors
- 👤 Satoshi Ichiyasu
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 17:50
CPC Classifications
B; B01; B01D; B01D39/00; B01D39/14; B01D39/16; B01D39/1607; B01D39/1623; B03; B03C; B03C3/00; B03C3/28
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
26 words
A composite filter material comprising: (a) at least one layer of porous fibrillated synthetic polymer resin; and (b) at least one layer of fibrous electret material.
Claim 2
Dependent Claim
26 words
A composite filter material comprising: (a) at least one layer of porous fibrillated synthetic polymer resin; and (b) at least one layer of fibrous electret material.
Claim 3
Dependent Claim
18 words
A filter material as claimed in claim 1, wherein said porous fibrillated synthetic polymer resin comprises porous polytetrafluoroethylene.
Claim 4
Dependent Claim
17 words
A filter material as claimed in claim 1 or 2, wherein said fibrous electret material comprises polypropylene.
Claim 5
Dependent Claim
24 words
A filter material as claimed in any preceding claim, wherein said layer of porous fibrillated synthetic polymer resin surrounds completely said fibrous electret material.
Claim 6
Dependent Claim
19 words
A filter assembly comprising a frame in which is mounted a filter material as claimed in any preceding claim.
Claim 7
Dependent Claim
28 words
A filter assembly as claimed in claim 5, in which the layer of porous fibrillated synthetic polymer resin is located on the downstream side of the filter material.
Claim 8
Dependent Claim
30 words
A filter assembly as claimed in claim 5 or 6, in which the layer of porous fibrillated synthetic polymer resin is located on the upstream side of the filter material.
References Cited (Backward Citations)
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