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US4278544A Expired / Lapsed US ⏱️ 0.0 years remaining

Filter medium for fluid

Assignee: Aikoh Co Ltd
•
Filing: 1980-03-26
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Granted: 1981-07-14
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Expires: 2000-03-26
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Abstract

Abstract A filter medium for fluid, which is a sintered body in which alumina refractory is 100 parts by weight, more than 95% by weight of said refractory being pelletized spheroids of less than 1.0 mm in particle size, while inorganic binder having particle size less than 40 microns is in the range 15-30 parts by weight and fluoride and/or oxide of lithium is in the range 0.1-1 part by weight, and in which filter medium the mean pore diameter is in the range 500-1 microns and the porosity is in the range from 15 to 40%.

Inventors

  • 👤 Masaru Takashima

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 16:51
CPC Classifications
C; C04; C04B; C04B38/00; B; B01; B01D; B01D39/00; B01D39/14; B01D39/20; B01D39/2068; B01D39/2072; B01D39/2075; C04B35/00; C04B35/01; C04B35/10; C04B2111/00; C04B2111/00474; C04B2111/00793

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 167 words
A filter medium for the filtration of a fluid at high temperatures which is a sintered body and has a mean pore diameter in the range of 500 microns to 1 mm and a porosity in the range of 15-40% which comprises: (a) 100 parts by weight of an alumina refractory, with more than 95% by weight of said refractory being pelletized spheroids having a particle size of less than 1.0 mm, said refractory being at least one material selected from the group consisting of alumina, corundum, mullite, bauxite, diaspore and sillimanite; (b) 15-30 parts by weight of an organic binder having a particle size less than 40 microns, with said binder being at least one material selected from the group consisting of kaolinite, bentonite, agalmatolite, burned alumina, sintered alumina, siliceous stone, feldspar, porcelian stone and glass; and (c) 0.1-1.0 parts by weight of a sintering aid wherein said sintering aid is at least one material selected from the group consisting of lithium fluoride and lithium oxide.
Claim 2
Dependent Claim 167 words
A filter medium for the filtration of a fluid at high temperatures which is a sintered body and has a mean pore diameter in the range of 500 microns to 1 mm and a porosity in the range of 15-40% which comprises: (a) 100 parts by weight of an alumina refractory, with more than 95% by weight of said refractory being pelletized spheroids having a particle size of less than 1.0 mm, said refractory being at least one material selected from the group consisting of alumina, corundum, mullite, bauxite, diaspore and sillimanite; (b) 15-30 parts by weight of an organic binder having a particle size less than 40 microns, with said binder being at least one material selected from the group consisting of kaolinite, bentonite, agalmatolite, burned alumina, sintered alumina, siliceous stone, feldspar, porcelian stone and glass; and (c) 0.1-1.0 parts by weight of a sintering aid wherein said sintering aid is at least one material selected from the group consisting of lithium fluoride and lithium oxide.

References Cited (Backward Citations)

US3235089A Cited
US3939079A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-07-13 1985-01-12 1985-07-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-07-13 1989-01-12 1989-07-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-07-13 1993-01-12 1993-07-14 $7700.00 Window Closed / Lapsed

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