US4230573A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cartridge filter and method of making same
Assignee: KER Associates Inc
•
Filing: 1979-06-08
•
Granted: 1980-10-28
•
Expires: 1999-06-08
Abstract
Abstract Cartridge filters of enhanced capture potential for fine contaminants, prepared by selective interaction of melamine formaldehyde bonding resin and polyamido/polyamine-epichlorhydrin charge modifier.
Inventors
- 👤 Michael Kilty
- 👤 Allan Pernigotti
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:33
CPC Classifications
B; B01; B01D; B01D39/00; B01D39/14; B01J; B01J47/00; B01J47/02; B01J47/022; B01J47/024; Y; Y10; Y10S; Y10S55/00; Y10S55/05
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
38 words
A cartridge filter comprising an integral at least semi-rigid self-supporting porous thick-walled tubular element consisting essentially of fibrous material bonded with a melamine-formaldehyde resin, the surfaces of the bonded fibrous material being modified with a polyamido/polyamine-epichlorhydrin cationic resin.
Claim 2
Dependent Claim
38 words
A cartridge filter comprising an integral at least semi-rigid self-supporting porous thick-walled tubular element consisting essentially of fibrous material bonded with a melamine-formaldehyde resin, the surfaces of the bonded fibrous material being modified with a polyamido/polyamine-epichlorhydrin cationic resin.
Claim 3
Dependent Claim
12 words
The cartridge filter of claim 1, wherein said melamine-formaldehyde resin is alkylated.
Claim 4
Dependent Claim
23 words
The cartridge filter of claim 1, wherein the weight ratio of fibrous material to binder resin is from about 7:3 to about 3:2.
Claim 5
Dependent Claim
23 words
The cartridge filter of claim 1, comprising an amount of polyamido/polyamine-epichlorhydrin resin sufficient to enhance the filtration efficiency of the bonded fibrous structure.
Claim 6
Dependent Claim
21 words
The cartridge filter of claim 1, comprising from about 1 to about 3 percent by weight of a polyamido/polyamine-epichlorhydrin cationic resin.
Claim 7
Dependent Claim
12 words
The cartridge filter of claim 1, further comprising a particulate filter aid.
Claim 8
Independent Claim
75 words
A method for the treatment of bonded cartridge filters comprising impregnating a dry preformed at least semi-rigid self-supporting thick-walled tubular filter element comprising fibrous material bonded into an integral porous structure with a melamine-formaldehyde resin with an aqueous solution of a polyamido/polyamine-epichlorhydrin cationic resin to provide a surface coating on the bonded fibrous surfaces sufficient to enhance filtration efficiency, and drying and curing the impregnated structure at a temperature of at least about 300° F.
Claim 9
Independent Claim
75 words
A method for the treatment of bonded cartridge filters comprising impregnating a dry preformed at least semi-rigid self-supporting thick-walled tubular filter element comprising fibrous material bonded into an integral porous structure with a melamine-formaldehyde resin with an aqueous solution of a polyamido/polyamine-epichlorhydrin cationic resin to provide a surface coating on the bonded fibrous surfaces sufficient to enhance filtration efficiency, and drying and curing the impregnated structure at a temperature of at least about 300° F.
Claim 10
Dependent Claim
11 words
The method of claim 7, wherein said melamine-formaldehyde resin is alkylated.
Claim 11
Dependent Claim
17 words
The method of claim 7 wherein the pH of the cationic resin solution is below about 6.3.
Claim 12
Dependent Claim
26 words
The method of claim 7 wherein from about 1 to 3 weight percent (dry basis) of said polyamido/polyamine-epichlorhydrin resin is incorporated into the bonded fibrous structure.
Claim 13
Independent Claim
61 words
A method for the preparation of cartridge filters comprising bonding a fibrous structure into an at least semi-rigid self-supporting porous thick-walled tubular element with a melamine-formaldehyde resin, treating the surfaces of the bonded interfelted fibrous structure with a polyamido/polyamine-epichlorhydrin resin, and drying and curing the treated structure at a temperature of at least about 300° F. to remove essentially all water.
Claim 14
Independent Claim
61 words
A method for the preparation of cartridge filters comprising bonding a fibrous structure into an at least semi-rigid self-supporting porous thick-walled tubular element with a melamine-formaldehyde resin, treating the surfaces of the bonded interfelted fibrous structure with a polyamido/polyamine-epichlorhydrin resin, and drying and curing the treated structure at a temperature of at least about 300° F. to remove essentially all water.
Claim 15
Dependent Claim
11 words
The method of claim 11, wherein the melamine-formaldehyde resin is alkylated.
Claim 16
Dependent Claim
14 words
The method of claim 11, wherein the drying is conducted at about 310°-330° F.
Claim 17
Dependent Claim
22 words
The method of claim 11 wherein the amount of polyamido/polyamine-epichlorhydrin resin is sufficient to enhance filtration efficiency of the bonded fibrous structure.
Claim 18
Dependent Claim
24 words
The method of claim 11 wherein the amount of polyamido/polyamine-epichlorhydrin resin is from about 1 to 3% by weight of the bonded fibrous structure.
Claim 19
Dependent Claim
16 words
The method of claim 11 wherein said drying is carried out in a static (oven) atmosphere.
Claim 20
Dependent Claim
23 words
The method of claim 11 wherein said polyamido/polyamine-epichlorhydrin cationic resin is applied as an aqueous solution having a pH of below about 6.3.
Claim 21
Dependent Claim
26 words
A method for the filtration of aqueous liquids at high flow rates and improved efficiency comprising passing said liquids through the cartridge filter of claim 1.
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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) | 1983-10-28 | 1984-04-28 | 1984-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-28 | 1988-04-28 | 1988-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-28 | 1992-04-28 | 1992-10-28 | $7700.00 | Window Closed / Lapsed |