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EP0488822A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Electret filters

Assignee: Mitsui Chemicals Inc
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Filing: 1991-12-02
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Granted: —
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Expires: 2011-12-02
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Abstract

Abstract An electret filter made of a resin whose angle of contact upon wetting with pure water is no smaller than 95 degrees, as well as an electret filter made of a resin whose angle of contact upon wetting with pure water has been adjusted to no smaller than 95 degrees by addition of silicone oil. Those electret filters have high trapping efficiency and their ability to trap particulates, especially cigarette smoke, will not deteriorate even if they are continuously used. Therefore, they can advantageously be used as filter media in many applications such as home and industrial air conditioners, air cleaners, fan heaters, vacuum cleaners, and air conditioning systems for common equipment.

Inventors

  • 👤 Satoshi C/O Mitsui Petrochem. Ind. Ltd. Matsuura
  • 👤 Tsuneo c/o MITSUI PETROCHEM. IND. LTD. Kishiba
  • 👤 Yoshio C/O Mitsui Petrochem. Ind. Ltd. Shinagawa

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-25 04:05
CPC Classifications
B; B01; B01D; B01D39/00; B01D39/14; B01D39/16; B01D39/1607; B01D39/1623; B03; B03C; B03C3/00; B03C3/28; Y; Y02; Y02A; Y02A50/00; Y02A50/20; Y02A50/2351; Y10; Y10S; Y10S55/00; Y10S55/05; Y10S55/39

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 64 words
An electret filter made of a resin whose angle of contact upon wetting with pure water is not less than 95 degrees or of a mixture of a resin whose angle of contact upon wetting with pure water is less than 95 degrees and a silicone oil, the mixture having an angle of contact upon wetting with pure water no smaller than 95 degrees.
Claim 2
Dependent Claim 58 words
An electret filter according to claim 1 made of a resin having an angle of contact no smaller than 95 degrees selected from poly-4-methyl-1-pentene, polytetra-fluoroethylene, a fluoroethylene-propylene copolymer or a perfluoroalkoxy fluorine resin, said resin being optionally modified with an unsaturated carboxylic acid, an unsaturated epoxy compound, an olefinically unsaturated organosilicon compound or an olefinically unsaturated organofluorine compound.
Claim 3
Dependent Claim 30 words
An electret filter according to claim 2 which further comprises an additional resin which is a polycarbonate resin, a polyamide based resin, a polyester based resin or a polyacrylic resin.
Claim 4
Dependent Claim 31 words
An electret filter according to claim 1 made of a mixture containing a resin having an angle of contact less than 95 degrees selected from propylene homopolymer, polyethyleneterephthalate, polymethacrylate or polycarbonate.
Claim 5
Dependent Claim 19 words
An electret filter according to claim 1 or 4 wherein said mixture contains 0.05 to 5 wt% silicone oil.

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